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Harish, Vancha, Devesh Tewari, Manish Gaur, Awadh Bihari Yadav, Shiv Swaroop, Mikhael Bechelany, and Ahmed Barhoum. "Review on Nanoparticles and Nanostructured Materials: Bioimaging, Biosensing, Drug Delivery, Tissue Engineering, Antimicrobial, and Agro-Food Applications." Nanomaterials 12, no. 3 (January 28, 2022): 457. http://dx.doi.org/10.3390/nano12030457.
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In the last few decades, the vast potential of nanomaterials for biomedical and healthcare applications has been extensively investigated. Several case studies demonstrated that nanomaterials can offer solutions to the current challenges of raw materials in the biomedical and healthcare fields. This review describes the different nanoparticles and nanostructured material synthesis approaches and presents some emerging biomedical, healthcare, and agro-food applications. This review focuses on various nanomaterial types (e.g., spherical, nanorods, nanotubes, nanosheets, nanofibers, core-shell, and mesoporous) that can be synthesized from different raw materials and their emerging applications in bioimaging, biosensing, drug delivery, tissue engineering, antimicrobial, and agro-foods. Depending on their morphology (e.g., size, aspect ratio, geometry, porosity), nanomaterials can be used as formulation modifiers, moisturizers, nanofillers, additives, membranes, and films. As toxicological assessment depends on sizes and morphologies, stringent regulation is needed from the testing of efficient nanomaterials dosages. The challenges and perspectives for an industrial breakthrough of nanomaterials are related to the optimization of production and processing conditions.
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Qu, Juntian, and Xinyu Liu. "Recent Advances on SEM-Based In Situ Multiphysical Characterization of Nanomaterials." Scanning 2021 (June 9, 2021): 1–16. http://dx.doi.org/10.1155/2021/4426254.
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Functional nanomaterials possess exceptional mechanical, electrical, and optical properties which have significantly benefited their diverse applications to a variety of scientific and engineering problems. In order to fully understand their characteristics and further guide their synthesis and device application, the multiphysical properties of these nanomaterials need to be characterized accurately and efficiently. Among various experimental tools for nanomaterial characterization, scanning electron microscopy- (SEM-) based platforms provide merits of high imaging resolution, accuracy and stability, well-controlled testing conditions, and the compatibility with other high-resolution material characterization techniques (e.g., atomic force microscopy), thus, various SEM-enabled techniques have been well developed for characterizing the multiphysical properties of nanomaterials. In this review, we summarize existing SEM-based platforms for nanomaterial multiphysical (mechanical, electrical, and electromechanical) in situ characterization, outline critical experimental challenges for nanomaterial optical characterization in SEM, and discuss potential demands of the SEM-based platforms to characterizing multiphysical properties of the nanomaterials.
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Tan, Qiaoyin, Cuicui Wu, Lei Li, Weide Shao, and Min Luo. "Nanomaterial-Based Prosthetic Limbs for Disability Mobility Assistance: A Review of Recent Advances." Journal of Nanomaterials 2022 (March 31, 2022): 1–10. http://dx.doi.org/10.1155/2022/3425297.
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The emergence of new hybrid nanomaterial has enabled prosthetic devices to have more performance and significantly improved the quality of life of the disabled. Due to the biosensing properties of prosthetic limbs made of nanomaterials, a large number of nanocomposites have been designed, developed, and evaluated for various prosthetic limbs, such as e-skin, e-skin’s neurotactility sensing, human prosthetic interface tissue engineering, bones, and biosensors. Nano-based materials are also considered to be the new generation of scientific and technological materials for the preparation of various prosthetic devices for the disabled, which can effectively improve the sense of use of the disabled and achieve functional diversity. The study described various nanomaterials for prosthetic devices, and introduced some basic components of nanocomposites; their applications are in three areas, such as bone, skin, and nerve, and evaluated and summarized the advantages of these applications. The results show that (1) carbon-based nanomaterials as neural materials have been studied most deeply. Due to that strong stability of the carbon-based material and the simple transmission mechanism, the cost can be controlled in manufacturing the artificial limb. Materials with human-computer interaction function are the research focus in the future. (2) Skin nanomaterials are mainly composite materials, generally containing metal- and carbon-based materials. Ionic gels, ionic liquids, hydrogels, and elastomers have become the focus of attention due to the sensitivity, multimodal, and memory properties of their materials. (3) Outstanding nanomaterials for bone are fibrous materials, metallic synthetic materials, and composite materials, with extremely high hardness, weight, and toughness. Of the skeletal materials, the choice of prosthetic socket material is the most important and is typically based on fiber laminate composites. Some of these materials make sensors for durability and performance that can be used for large-scale clinical testing.
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Kim, Sung-Hyun, So-Hye Hong, Jin Hee Lee, Dong Han Lee, Kikyung Jung, Jun-Young Yang, Hyo-Sook Shin, JeongPyo Lee, Jayoung Jeong, and Jae-Ho Oh. "Skin Sensitization Evaluation of Carbon-Based Graphene Nanoplatelets." Toxics 9, no. 3 (March 17, 2021): 62. http://dx.doi.org/10.3390/toxics9030062.
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Graphene nanoplatelets (GNPs) are one of the major types of carbon based nanomaterials that have different industrial and biomedical applications. There is a risk of exposure to GNP material in individuals involved in their large-scale production and in individuals who use products containing GNPs. Determining the exact toxicity of GNP nanomaterials is a very important agenda. This research aimed to evaluate the skin sensitization potentials induced by GNPs using two types of alternative to animal testing. We analyzed the physicochemical characteristics of the test material by selecting a graphene nanomaterial with a nano-size on one side. Thereafter, we evaluated the skin sensitization effect using an in vitro and an in vivo alternative test method, respectively. As a result, we found that GNPs do not induce skin sensitization. In addition, it was observed that the administration of GNPs did not induce cytotoxicity and skin toxicity. This is the first report of skin sensitization as a result of GNPs obtained using alternative test methods. These results suggest that GNP materials do not cause skin sensitization, and these assays may be useful in evaluating the skin sensitization of some nanomaterials.
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Akono, Ange-Therese. "Fracture toughness of one- and two-dimensional nanoreinforced cement via scratch testing." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 379, no. 2203 (June 21, 2021): 20200288. http://dx.doi.org/10.1098/rsta.2020.0288.
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Cement is the most widely consumed material globally, with the cement industry accounting for 8% of human-caused greenhouse gas emissions. Aiming for cement composites with a reduced carbon footprint, this study investigates the potential of nanomaterials to improve mechanical characteristics. An important question is to increase the fraction of carbon-based nanomaterials within cement matrices while controlling the microstructure and enhancing the mechanical performance. Specifically, this study investigates the fracture response of Portland cement reinforced with one- and two-dimensional carbon-based nanomaterials, such as carbon nanofibres, multiwalled carbon nanotubes, helical carbon nanotubes and graphene oxide nanoplatelets. Novel processing routes are shown to incorporate 0.1–0.5 wt% of nanomaterials into cement using a quadratic distribution of ultrasonic energy. Scratch testing is used to probe the fracture response by pushing a sphero-conical probe against the surface of the material under a linearly increasing vertical force. Fracture toughness is then computed using a nonlinear fracture mechanics model. Nanomaterials are shown to bridge nanoscale air voids, leading to pore refinement, and a decrease in the porosity and the water absorption. An improvement in fracture toughness is observed in cement nanocomposites, with a positive correlation between the fracture toughness and the mass fraction of nanofiller for graphene-reinforced cement. Moreover, for graphene-reinforced cement, the fracture toughness values are in the range of 0.701 to 0.717 MPa m . Thus, this study illustrates the potential of nanomaterials to toughen cement while improving the microstructure and water resistance properties. This article is part of a discussion meeting issue ‘A cracking approach to inventing new tough materials: fracture stranger than friction’.
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Wohlleben, Wendel, Bryan Hellack, Carmen Nickel, Monika Herrchen, Kerstin Hund-Rinke, Katja Kettler, Christian Riebeling, et al. "The nanoGRAVUR framework to group (nano)materials for their occupational, consumer, environmental risks based on a harmonized set of material properties, applied to 34 case studies." Nanoscale 11, no. 38 (2019): 17637–54. http://dx.doi.org/10.1039/c9nr03306h.
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Kumpati, Ramesh, Wojciech Skarka, and Sunith Kumar Ontipuli. "Current Trends in Integration of Nondestructive Testing Methods for Engineered Materials Testing." Sensors 21, no. 18 (September 15, 2021): 6175. http://dx.doi.org/10.3390/s21186175.
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Material failure may occur in a variety of situations dependent on stress conditions, temperature, and internal or external load conditions. Many of the latest engineered materials combine several material types i.e., metals, carbon, glass, resins, adhesives, heterogeneous and nanomaterials (organic/inorganic) to produce multilayered, multifaceted structures that may fail in ductile, brittle, or both cases. Mechanical testing is a standard and basic component of any design and fabricating process. Mechanical testing also plays a vital role in maintaining cost-effectiveness in innovative advancement and predominance. Destructive tests include tensile testing, chemical analysis, hardness testing, fatigue testing, creep testing, shear testing, impact testing, stress rapture testing, fastener testing, residual stress measurement, and XRD. These tests can damage the molecular arrangement and even the microstructure of engineered materials. Nondestructive testing methods evaluate component/material/object quality without damaging the sample integrity. This review outlines advanced nondestructive techniques and explains predominantly used nondestructive techniques with respect to their applications, limitations, and advantages. The literature was further analyzed regarding experimental developments, data acquisition systems, and technologically upgraded accessory components. Additionally, the various combinations of methods applied for several types of material defects are reported. The ultimate goal of this review paper is to explain advanced nondestructive testing (NDT) techniques/tests, which are comprised of notable research work reporting evolved affordable systems with fast, precise, and repeatable systems with high accuracy for both experimental and data acquisition techniques. Furthermore, these advanced NDT approaches were assessed for their potential implementation at the industrial level for faster, more accurate, and secure operations.
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Wang, Jingang, Xijiao Mu, and Mengtao Sun. "The Thermal, Electrical and Thermoelectric Properties of Graphene Nanomaterials." Nanomaterials 9, no. 2 (February 6, 2019): 218. http://dx.doi.org/10.3390/nano9020218.
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Graphene, as a typical two-dimensional nanometer material, has shown its uniqueapplication potential in electrical characteristics, thermal properties, and thermoelectric propertiesby virtue of its novel electronic structure. The field of traditional material modification mainlychanges or enhances certain properties of materials by mixing a variety of materials (to form aheterostructure) and doping. For graphene as well, this paper specifically discusses the use oftraditional modification methods to improve graphene’s electrical and thermoelectrical properties.More deeply, since graphene is an atomic-level thin film material, its shape and edge conformation(zigzag boundary and armchair boundary) have a great impact on performance. Therefore, thispaper reviews the graphene modification field in recent years. Through the change in the shape ofgraphene, the change in the boundary structure configuration, the doping of other atoms, and theformation of a heterostructure, the electrical, thermal, and thermoelectric properties of graphenechange, resulting in broader applications in more fields. Through studies of graphene’s electrical,thermal, and thermoelectric properties in recent years, progress has been made not only inexperimental testing, but also in theoretical calculation. These aspects of graphene are reviewed inthis paper.
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Gandhi, Mansi, and Khairunnisa Amreen. "Emerging Trends in Nanomaterial-Based Biomedical Aspects." Electrochem 4, no. 3 (August 4, 2023): 365–88. http://dx.doi.org/10.3390/electrochem4030024.
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Comprehending the interfacial interaction of nanomaterials (NMs) and biological systems is a significant research interest. NMs comprise various nanoparticles (NPs) like carbon nanotubes, graphene oxides, carbon dots, graphite nanopowders, etc. These NPs show a variety of interactions with biological interfaces via organic layers, therapeutic molecules, proteins, DNA, and cellular matrices. A number of biophysical and colloidal forces act at the morphological surface to regulate the biological responses of bio-nanoconjugates, imparting distinct physical properties to the NMs. The design of future-generation nano-tools is primarily based on the basic properties of NMs, such as shape, size, compositional, functionality, etc., with studies being carried out extensively. Understanding their properties promotes research in the medical and biological sciences and improves their applicability in the health management sector. In this review article, in-depth and critical analysis of the theoretical and experimental aspects involving nanoscale material, which have inspired various biological systems, is the area of focus. The main analysis involves different self-assembled synthetic materials, bio-functionalized NMs, and their probing techniques. The present review article focuses on recent emerging trends in the synthesis and applications of nanomaterials with respect to various biomedical applications. This article provides value to the literature as it summarizes the state-of-the-art nanomaterials reported, especially within the health sector. It has been observed that nanomaterial applications in drug design, diagnosis, testing, and in the research arena, as well as many fatal disease conditions like cancer and sepsis, have explored alongwith drug therapies and other options for the delivery of nanomaterials. Even the day-to-day life of the synthesis and purification of these materials is changing to provide us with a simplified process. This review article can be useful in the research sector as a single platform wherein all types of nanomaterials for biomedical aspects can be understood in detail.
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Konstantopoulos, Georgios, Elias P. Koumoulos, and Costas A. Charitidis. "Digital Innovation Enabled Nanomaterial Manufacturing; Machine Learning Strategies and Green Perspectives." Nanomaterials 12, no. 15 (August 1, 2022): 2646. http://dx.doi.org/10.3390/nano12152646.
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Machine learning has been an emerging scientific field serving the modern multidisciplinary needs in the Materials Science and Manufacturing sector. The taxonomy and mapping of nanomaterial properties based on data analytics is going to ensure safe and green manufacturing with consciousness raised on effective resource management. The utilization of predictive modelling tools empowered with artificial intelligence (AI) has proposed novel paths in materials discovery and optimization, while it can further stimulate the cutting-edge and data-driven design of a tailored behavioral profile of nanomaterials to serve the special needs of application environments. The previous knowledge of the physics and mathematical representation of material behaviors, as well as the utilization of already generated testing data, received specific attention by scientists. However, the exploration of available information is not always manageable, and machine intelligence can efficiently (computational resources, time) meet this challenge via high-throughput multidimensional search exploration capabilities. Moreover, the modelling of bio-chemical interactions with the environment and living organisms has been demonstrated to connect chemical structure with acute or tolerable effects upon exposure. Thus, in this review, a summary of recent computational developments is provided with the aim to cover excelling research and present challenges towards unbiased, decentralized, and data-driven decision-making, in relation to increased impact in the field of advanced nanomaterials manufacturing and nanoinformatics, and to indicate the steps required to realize rapid, safe, and circular-by-design nanomaterials.
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Balopoulos, Victor D., Nikolaos Archontas, and Stavroula J. Pantazopoulou. "Model of the Mechanical Behavior of Cementitious Matrices Reinforced with Nanomaterials." Journal of Engineering 2017 (2017): 1–10. http://dx.doi.org/10.1155/2017/7329540.
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CNTs and CNFs have been introduced as a nanoscale reinforcing material to cementitious composites, for stiffening and strengthening the microstructure. This technology is motivated by the need to control crack initiation in the cementitious gel before it propagates into visible crack formations. Experimental evidence supports this concept; however, testing at the nanoscale may only be conducted through nanoindentation, which has a limited range only providing localized results that cannot be extrapolated to general stress states. To evaluate the restraining action of nanomaterials in the gel microstructure, a computational mechanistic model has been developed where the material phases (gel, nanotubes, and pores) are modeled explicitly allowing for natural randomness in their distribution and orientation. Repeated analysis with identical input data reproduces the statistical scatter observed in laboratory tests on identical material samples. The formulation uses a discrete element approach; the gel structure is represented by a random network of hydrates and successfully reproduces the known trends in mechanical behavior of cementitious materials (pressure and restraint sensitive material behavior) and the small ratio of tensile to compressive strength. Simulations illustrate that it is possible to computationally reproduce the measured properties and behavior of fiber-reinforced cement composites using information from simple laboratory tests.
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Jweeg, Muhsin J., Emad K. Njim, Orhan S. Abdullah, Mohsin A. Al-Shammari, Muhannad Al-Waily, and Sadeq H. Bakhy. "Free Vibration Analysis of Composite Cylindrical Shell Reinforced with Silicon Nano-Particles: Analytical and FEM Approach." Physics and Chemistry of Solid State 24, no. 1 (February 23, 2023): 26–33. http://dx.doi.org/10.15330/pcss.24.1.26-33.
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Previous research presented the effect of nanomaterials on the mechanical properties of composite materials with various volume fraction effects; in addition, their research presented the effect of nanomaterials on the same mechanical characteristics for a composite plate structure, such as vibration and thermal buckling behavior. Therefore, since the use of shell structures is for large applications, it is necessary to investigate the modification of the vibration characteristics of its design with the effect of nanomaterials and study the influence of other reinforced nanoparticle types on its features. Therefore, in this work, silicon nanoparticles were selected to investigate their effect on the vibration behavior of a shell structure. As a result, this work included studying the vibration behavior by testing the shell structure with a vibration test machine. In addition, after manufacturing the composite material shell with various silicon volume fractions, the mechanical properties were evaluated. In addition, the finite element technique with the Ansys program was used to assess and compare the vibration behavior of the shell structure using the numerical technique. The comparison of the results gave an acceptable percentage error not exceeding 10.93%. Finally, the results evaluated showed that the modification with silicon nanomaterials gave very good results since the nanomaterials improved about 65% of the shell's mechanical properties and vibration characteristics.
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Kaadhm, Ehab Q., Khansaa D. Salman, and Ahmed H. Reja. "Investigating The Effect of Magnetite (Fe3O4) Nanoparticles on Mechanical Properties of Epoxy Resin." Engineering and Technology Journal 39, no. 6 (June 25, 2021): 986–95. http://dx.doi.org/10.30684/etj.v39i6.2063.
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In this paper, study the effects of magnetite nanomaterial Fe3O4 on the mechanical properties of epoxy. Dispersion of Fe3O4 nanoparticles in the epoxy resin was performed by ultrasonication. The samples of the nanocomposites were prepared using the casting method. The nanocomposites contain epoxy resins as a matrix material incorporated by different weight percentages of magnetite Fe3O4 that varies from 0wt.% to 15wt.% as a reinforcing material. The epoxy with the additive reinforcement materials Fe3O4 was slowly mixed in a sonication bath for 15 minutes, then the mixture poured into silicon molds. Field Emission Scanning Electron Microscopy FESEM and X-ray diffraction spectra XRD were used to characterize the morphological and structural properties of preparing samples and the distribution of Fe3O4 nanoparticles to the epoxy resin. Mechanical testing consists of tensile, hardness shore, and three-point flexural tests were performed on the samples at room temperature according to ASTM standards. The results showed that reinforcement by 15wt.% of Fe3O4 nanoparticles maximizes these mechanical properties of nanocomposites compared with pure epoxy except for the young modulus's preferred weight at 9 wt.%, this is due to aggregation of the additives nanomaterials in epoxy resin above 9 wt.%.
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Topolář, Libor, Hana Šimonová, Pavel Rovnaník, and Pavel Schmid. "The Effect of the Carbon Nanotubes on the Mechanical Fracture Properties of Alkali Activated Slag Mortars." Applied Mechanics and Materials 617 (August 2014): 243–46. http://dx.doi.org/10.4028/www.scientific.net/amm.617.243.
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New nanomaterials such as carbon nanotubes and nanofibres considerably improve performance of current building materials and they can contribute to new application facilities. Alkali activated slag is a material having a great potential to be used in practice. The main drawback of this material is a high level of autogenous and especially drying shrinkage, which causes a deterioration of the mechanical fracture properties. The aim of this paper is introduce the effect of carbon nanotubes admixture on the microstucture and mechanical performance of alkali activated slag mortars. The three-point bending tests of specimens with central edge notch were performed. Method of acoustic emission was used during this testing.
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Carrasco, Carla Ribalta, Ana Sofia Fonseca, Anna Pohl, Alexis Vignes, Søren S. Bjerregaard, Neeraj Shandilya, Douglas Evans, Thomas A. J. Kuhlbusch, Jacques Bouillard, and Keld A. Jensen. "109 Inter- and Intra-Laboratory Comparison of 6 Dustiness Testing Methods: Towards the Development of an OECD Testing Guideline." Annals of Work Exposures and Health 67, Supplement_1 (May 1, 2023): i97. http://dx.doi.org/10.1093/annweh/wxac087.238.
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Abstract Dustiness is a key parameter describing the ability of powder materials to generate dust during agitation. The main goal of this work was to generate and assess the scientific basis for the validation and applicability of 6 dustiness methods to nanomaterials, and development of a subsequent OECD testing guideline. Six dustiness methods (rotating drum, small rotating drum, continuous drop, vortex shaker, fluidizer and venturi) were subjected to an intra- and inter-laboratory comparison (ILC) in which 15 international laboratories participated. ILC tests were conducted for 6 materials (3 TiO2 and 3 SiO2) of different chemical natures and dustiness levels. Each participating laboratory conducted at least 3 replicates per material. Harmonization of procedures, methods and data treatment took place prior to testing. Results from the ILC were assessed considering the different reported metrics such as respirable mass and particle number dustiness index. Overall, the intralaboratory variability for the different methods and metrics was under 30%. Variation between laboratories was generally higher for respirable mass than particle number dustiness index. These variations were mostly attributed to differences in setups such as tubing length or instrumentation. All methods except the venturi, which was characteristic for presenting low differences between materials and opposed classification to the rest of the methods, showed relatively similar material ranking. For all methods and laboratories the calculated z-score (measure of the deviation of each laboratory from the true value) was <2 as based on ISO 13528, which indicates gratifying results. Funding: EU H2020 Research and Innovation Programme under Grant Agreement 814401.
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Carnovale, Catherine, Daniela Guarnieri, Luisana Di Cristo, Isabella De Angelis, Giulia Veronesi, Alice Scarpellini, Maria Ada Malvindi, Flavia Barone, Pier Paolo Pompa, and Stefania Sabella. "Biotransformation of Silver Nanoparticles into Oro-Gastrointestinal Tract by Integrated In Vitro Testing Assay: Generation of Exposure-Dependent Physical Descriptors for Nanomaterial Grouping." Nanomaterials 11, no. 6 (June 17, 2021): 1587. http://dx.doi.org/10.3390/nano11061587.
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Grouping approaches of nanomaterials have the potential to facilitate high throughput and cost effective nanomaterial screening. However, an effective grouping of nanomaterials hinges on the application of suitable physicochemical descriptors to identify similarities. To address the problem, we developed an integrated testing approach coupling acellular and cellular phases, to study the full life cycle of ingested silver nanoparticles (NPs) and silver salts in the oro-gastrointestinal (OGI) tract including their impact on cellular uptake and integrity. This approach enables the derivation of exposure-dependent physical descriptors (EDPDs) upon biotransformation of undigested nanoparticles, digested nanoparticles and digested silver salts. These descriptors are identified in: size, crystallinity, chemistry of the core material, dissolution, high and low molecular weight Ag-biomolecule soluble complexes, and are compared in terms of similarities in a grouping hypothesis. Experimental results indicate that digested silver nanoparticles are neither similar to pristine nanoparticles nor completely similar to digested silver salts, due to the presence of different chemical nanoforms (silver and silver chloride nanocrystals), which were characterized in terms of their interactions with the digestive matrices. Interestingly, the cellular responses observed in the cellular phase of the integrated assay (uptake and inflammation) are also similar for the digested samples, clearly indicating a possible role of the soluble fraction of silver complexes. This study highlights the importance of quantifying exposure-related physical descriptors to advance grouping of NPs based on structural similarities.
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Timothy Oladele Odedele and Hussaini Doko Ibrahim. "Advancing risk assessment of engineered nanomaterials using deep learning approach." World Journal of Advanced Engineering Technology and Sciences 6, no. 1 (June 30, 2022): 073–85. http://dx.doi.org/10.30574/wjaets.2022.6.1.0073.
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Nanotechnology is a novel technology that develops material at a size of 100 nm or less which has become beneficial in various human endeavors because of its unique characteristic features. Nano-materials are utilized in medicine, Engineering, and agricultural industries. The unique properties of these materials are applied for beneficial purposes and at the same time may also have negative toxicological and environmental impacts. Considering the impacts on the environment and human health, nanomaterials could be harmful because they are easily distributed through the environment, aquatic, and human systems. Particularly in human body system, the unique properties have made its transportation and distribution through the skin, lungs, gastrointestinal tract very easy. However, several toxicological studies have shown considerable inherent toxicity of some nano-particles to living organisms, and their negative and harmful effects on the environment and aquatic systems for which both quantitative structure activity relationship and relatively tedious animal testing procedures are available in various literatures for their characterization. Because of the large number of nanoparticles manufactured with the different intrinsic properties especially sizes and coatings, there is therefore need to explore an alternative approach that will not necessitate conducting test on every nano-particle produced. It is the apprehensions of these potentially harmful effects of nanomaterials that constitute serious setback to nanotechnology commercialization. The objective of the study is to develop intelligent models to assess, evaluate, and manage the inherent risks. In view of these side effects, there is therefore the need to design and develop classification and nanomaterials toxicity predictive models using deep learning intelligent systems. This paper, therefore, focuses on the capability of deep learning techniques to model physicochemical properties and toxic effects of nanomaterials. Hence, the main motivation of this research work is to assist the users of nanomaterials in classifying, assessing and determining the risk of nanomaterials toxicity.
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Lin, Kuan-Jiuh. "Preparation of high-efficiency anti-reflective oxide electrodes and their application in biomedical testing and thin-film lithium batteries." Impact 2022, no. 3 (June 30, 2022): 6–8. http://dx.doi.org/10.21820/23987073.2022.3.6.
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Nanomaterials hold great potential in the development of lithium-ion microbatteries and could assist in developing ever smaller and more reliable power sources to facilitate 21st Century life. Professor Kuan-Jiuh Lin is based in the Department of Chemistry, National Chung Hsing University, Taiwan, and runs the Interfacial Optical-Electronic (IOE) Lab. He and his team leader Dr Wen-Yin Ko are working to address gaps in nanotechnology, including how to conquer the strong interfacial coupling between the porous semiconductor membrane and the electro-plasmon metal-surface film. Their research is expected to have broad applications across electronics and optoelectronics. In a recent project, the researchers are working to develop more efficient lithium-ion microbatteries (micro-LIBs) using active nanostructured anode materials such as carbon nanomaterials composed of porous carbon, graphene and carbon nanotubes (CNTs). The researchers have developed a lightweight and high-rate CNT-based anode system that holds great potential for fast-charging batteries. The team has also created metal-doped MnO2 nanowalls with inter-networked vertically-oriented three-dimensional (3D) porous frameworks directly onto a AgCNT modified current collector, resulting in a superior performance anode material for LIBs. The researchers also created a novel 3D porous scaffold anode material of silicon–porphyrin pearl-chain-like nanowires which was placed onto the surface of a bundled titanium dioxide (TiO2) nanowire. In a world first, Lin and the team were able to achieve dial functionalities of antireflective and electrochemical properties-based anatase TiO2 nanowire devices with a high-porosity cross-linked geometry directly grown onto transparent conductive glass.
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Pokorski, Pawel, Vicki Stone, and Fiona Murphy. "2 Humanising Nanotoxicology Testing: Moving Towards Animal-free Approaches for Hazard Assessment of Nanomaterials." Annals of Work Exposures and Health 67, Supplement_1 (May 1, 2023): i87. http://dx.doi.org/10.1093/annweh/wxac087.211.
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Abstract The vast array of nanomaterials (NMs) under development raises ethical concerns over the reliance and extent of animal usage in the hazard assessment of substances. Grouping which allows read-across of data from NMs predicted to pose similar hazard could provide justification for waiving of in vivo tests. The GRACIOUS Framework has defined Integrated Approaches to Testing and Assessment (IATAs) to guide the generation of data to support grouping. Each IATA is underpinned by a tiered testing strategy promoting the use of acellular and in vitro assays, (Tier 1-2), which are predictive of in vivo mechanisms of toxicity. Tier 3 in vivo studies are only required to confirm grouping or fill specific gaps. Adopting the IATA approach allows the effective triage of vast number of NMs prioritized for in vivo hazard assessment, thus reducing overall animal testing. However, many of the methods recommended at Tier 1-2 are reliant on the use of animal-derived materials and reagents. The information gathered at early Tiers therefore cannot be considered animal-free unless adaptions are made to standard in vitro protocols to replace all animal-derived reagents. The objective of this study was to review the GRACIOUS Inhalation IATA and identify where animal-free options could be selected when designing experimental hazard studies. The replacement of animal-derived reagents with human alternatives was trialed in multiple Tier 1 assays using a CuO NM as a case study material. This proof-of-concept study informs the suitability of animal-free methods for NM hazard assessment and demonstrates only minor adaptions may be required.
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EL-kashif, Emad F., Shaimaa A. Esmail, Omayma AM Elkady, BS Azzam, and Ali A. Khattab. "Influence of carbon nanotubes on the properties of friction composite materials." Journal of Composite Materials 54, no. 16 (December 3, 2019): 2101–11. http://dx.doi.org/10.1177/0021998319891772.
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Carbon nanotubes have a lot of applications in mechanical fields. This is because nanomaterials have many superior mechanical properties such as very high strength-to-weight ratio, high modulus-to-weight ratio, high corrosion resistance, and super intelligence properties, which make them as smart materials. One of these attractive applications is the use of carbon nanotubes in vehicle brake friction material. Therefore, the fabrication and testing processes of these nanomaterials should be performed carefully to evaluate their mechanical, tribological, and noise properties. In this paper, friction material mixed with carbon nanotubes have been fabricated with different carbon nanotube contents and the same fabrication parameters. The carbon nanotubes have been produced using the conventional submerged arc discharge technique. The produced friction materials have been cut into pieces with standard sizes and then tested mechanically and tribologically. The results of tests have illustrated that the addition of carbon nanotubes into the friction materials could improve their mechanical properties (hardness, strength, and modulus) and also could enhance their tribological properties (wear rate and friction coefficient). Moreover, the tests showed that the presence of carbon nanotubes in friction materials could reduce the noise, vibration of the friction materials, and reduce the temperature rise due to the effect of friction, which means that the carbon nanotubes could raise the thermal conductivity of friction material, while the friction coefficient has stayed within the allowable standard limits (0.35–0.45). Surface morphology shows that the presence of carbon nanotubes in the friction materials could help to avoid surface friction cracks or fins within the normal operating conditions. The good combination of mechanical and tribological properties was obtained at 0.5% carbon nanotubes.
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Khenyab, Ali Yousuf, Raad Mohammed Abed, Ali Raad Hassan, and Hussain Jasim M. Al-Alkawi. "Improving the property of wear rate and hardness by adding hybrid nanomaterials to AA7075." Eastern-European Journal of Enterprise Technologies 2, no. 12 (116) (April 30, 2022): 30–36. http://dx.doi.org/10.15587/1729-4061.2022.255331.
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Aluminum alloys have become an essential material in many modern applications, such as automobiles, marines and aviation industries. It is expected that more applications will heavily depend on aluminum alloys to reduce the weight and maintain safety standards, many previous studies have done in this regard. Numerous of these applications’ parts could be subjected to different loading and environmental conditions. This includes wearing stress and loss of the surface properties. To address these issues, intensive researches have been conducted aiming to improve aluminum wear resistance. However, there is an increasing demand to provide a comprehensive understanding of the mechanisms of enhancing wear resistance. Preparation of nano-materials combined with aluminum alloy can be made in several known metallurgical methods. One of the most important difficulties and challenges faced in the manufacture of these nano-materials is to obtain a homogeneous mixture that does not have manufacturing defects. The present work aims to process and evaluate the Nano-hybrid composites of with different ratios of (Cu+Ti) mixed with AA7075 by using the liquid stir casting method by using (pin-on-disc) wear testing apparatus. The results showed when using multiple speeds and different loads in practical experiments, that the volumetric wear loss increase from 2.8 mm3 to 29.89 mm3 for zero–Nano and from 0.889 mm3 to 3.09 mm3 for 0.8 %+0.3 % (Cu+Ti) composite at speed 100 to 300 respectively. And from 12.81 mm3 to 0.889 mm3 at 25N. The coefficient of friction is reduced with the addition of reinforced material at 0.8 %+0.3 % (Cu+Ti) composite from 0.172 to 0.05. The hardness (BH) of the prepared composites increases with increasing the amount of hybrid Nano–reinforced materials. The enhancement percentage of 25.4 % is attained compared to the matrix material. These additions, which were in certain proportions, improved the mechanical properties
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Sachan, Dhruvendra Singh, K. Jaisimha Reddy, Akhilesh Mishra, Avinash Kumar Rai, Anam Khan, Barinderjit Singh, and Charu Rajpal. "Nanomaterials and Diverse Agricultural Applications: A Comprehensive Review." International Journal of Environment and Climate Change 13, no. 9 (June 27, 2023): 131–40. http://dx.doi.org/10.9734/ijecc/2023/v13i92215.
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Climate change, the population explosion and the growing demand for good food and health require better, more reliable and more efficient. The different shape, size, composition and ability to interact with organic compounds make nanomaterials and technology widely used. Nano formulations and their applications in agriculture in the form of agrochemicals for crop protection, toxicity identification by nanobiosensors, genetic manipulation of plants treated by nanodevices, and rapid and efficient diseases of plants. The delivery of genetic material and proteins via nano-arrays has been proven in crop engineering, drug delivery and environmental monitoring. Nanotechnology also benefits the food industry by improving all stages of food production from food processing to production, processing, packaging, safety, extending shelf life, testing for disease and creating smart foods. Therefore, technology can meet the needs of most consumers, including the improvement of food products and their sensations, and can improve product quality, texture soft and nutritious food without affecting its natural properties.
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Bates, Matthew E., Sabrina Larkin, Jeffrey M. Keisler, and Igor Linkov. "How decision analysis can further nanoinformatics." Beilstein Journal of Nanotechnology 6 (July 22, 2015): 1594–600. http://dx.doi.org/10.3762/bjnano.6.162.
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The increase in nanomaterial research has resulted in increased nanomaterial data. The next challenge is to meaningfully integrate and interpret these data for better and more efficient decisions. Due to the complex nature of nanomaterials, rapid changes in technology, and disunified testing and data publishing strategies, information regarding material properties is often illusive, uncertain, and/or of varying quality, which limits the ability of researchers and regulatory agencies to process and use the data. The vision of nanoinformatics is to address this problem by identifying the information necessary to support specific decisions (a top-down approach) and collecting and visualizing these relevant data (a bottom-up approach). Current nanoinformatics efforts, however, have yet to efficiently focus data acquisition efforts on the research most relevant for bridging specific nanomaterial data gaps. Collecting unnecessary data and visualizing irrelevant information are expensive activities that overwhelm decision makers. We propose that the decision analytic techniques of multicriteria decision analysis (MCDA), value of information (VOI), weight of evidence (WOE), and portfolio decision analysis (PDA) can bridge the gap from current data collection and visualization efforts to present information relevant to specific decision needs. Decision analytic and Bayesian models could be a natural extension of mechanistic and statistical models for nanoinformatics practitioners to master in solving complex nanotechnology challenges.
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Fu, Chao, Chunyan Xie, Jing Liu, Xiuli Wei, and Dake Wu. "A Comparative Study on the Effects of Three Nano-Materials on the Properties of Cement-Based Composites." Materials 13, no. 4 (February 13, 2020): 857. http://dx.doi.org/10.3390/ma13040857.
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The application of nano-materials to modify construction materials has become a research hotspot in recent years, but often different scholars use different research methods and reach different conclusions about the same material, which is not conducive to the performance comparison between different materials. In this paper, nano-SiO2, carbon nanotubes (CNTs) and nanocrystalline cellulose (NCC) were used as raw materials to prepare cement-based composites to compare the effects of the three nanomaterials on the mechanical and water absorption properties under the same experimental conditions, and their principles were investigated via The scanning electron microscope (SEM), X-Ray Diffraction (XRD) and other microscopic analysis testing methods. At the same time, strength benefit indexes are introduced to comprehensively evaluate the economics of the strength improvement provided by the three kinds of nanomaterial. The results show that doping with nano-SiO2, CNTs and NCC can promote the hydration process of cement effectively. The composite material exhibits excellent mechanical properties at the macro level because of the nucleation and filling effect of nano-SiO2, and the bridging and strengthening effects of CNTs and NCC. The compressive strength increased by 45.13%, 28.31% and 44.19% at 7d, and 23.09%, 18.40% and 23.40% at 28d. The flexural strength of 7d increased by 31.00%, 36.22 and 54.81%, and 14.91%, 22.23% and 30.46% at 28d. The water absorption is SiO2 < NCC < CNTs, and the nano-SiO2 is lower than the other two materials at least 15.54%. CNTs group has the lowest compressive strength benefit, which is 16.91 yuan/m3, and the lowest flexural strength benefit is NCC, which is 3.59 yuan/m3.
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Zhang, Yanjun, Yaxin Zhao, Rui Guo, Zengxing Zhang, Dan Liu, and Chenyang Xue. "Effect of L-Ascorbic Acid Solution Concentration on the Thermoelectric Properties of Silver Selenide Flexible Films Prepared by Vacuum-Assisted Filtration." Nanomaterials 12, no. 4 (February 12, 2022): 624. http://dx.doi.org/10.3390/nano12040624.
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Currently, there are several thermoelectric materials, such as Ag2Te, Bi2Te3, and Sb2Te3, that have been investigated for thermoelectric applications. However, the toxicity and rarity of most of these materials make them unsuitable for practical applications. In contrast, silver selenide (Ag2Se) is an abundant and environment-friendly thermoelectric material. This study provides a facile synthetic approach for preparing high-performance, low-cost, and flexible Ag2Se thermoelectric films. Ag2Se nanomaterials were prepared based on the chemical template method, and the reaction solution concentration was varied to systematically investigate the effects of reaction solution concentration on the characterization and thermoelectric properties of Ag2Se nanomaterials. For convenience of testing, the flexible Ag2Se films were prepared on porous nylon membranes using vacuum-assisted filtration. The prepared thermoelectric films were tested using an X-ray diffractometer, scanning electron microscope, Seebeck coefficient tester, and Hall tester. The film prepared from the solution with the lowest concentration (18.0 mM) demonstrated the best thermoelectric performance, with a maximum power factor of 382.18 μW∙m−1∙K−2 at ~400 K. Additionally, a cold-pressing treatment could effectively enhance the electrical conductivity of the film, without damaging the substrate, as the conductivity of the film remained at 90% of the original value after 1500 bending cycles.
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Selyutin, G. E., and A. V. Dunaev. "Nanoscale tribological materials." Sel'skohozjajstvennaja tehnika: obsluzhivanie i remont (Agricultural Machinery: Service and Repair), no. 10 (October 1, 2021): 49–55. http://dx.doi.org/10.33920/sel-10-2110-07.
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The results of the development and testing of nanodiamond triboactive from Krasnoyarsk Institute of chemistry and chemical technology, Krasnoyarsk Institute of Biophysics together with "RealDzerjinsk", as well as the results of the development of the new triboactive based on nano carbon fibers. It is proved that in contrast to pure nanodiamond powders imported nanomaterials explosion technologies graphite represent pseudoalpina nanoparticles surrounded by a carbon shell. Saturating them various peripheral organic compounds can be sedimentary stable carbon clusters, working at friction in oil is not for mechanism sergiovanni, and the mechanism of chemisorption and polymerization components triborate. A new, more technologically advanced and cheaper tribological material GRAF SB on the basis of on nano carbon fibers, are no less effective nanodiamond, only works on mechanism of adsorption and chemisorption.
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Selyutin, G. E., and A. V. Dunaev. "Сarbon nanoscale tribological materials." Sel'skohozjajstvennaja tehnika: obsluzhivanie i remont (Agricultural Machinery: Service and Repair), no. 5 (May 1, 2020): 18–24. http://dx.doi.org/10.33920/sel-10-2005-03.
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The results of the development and testing of nanodiamond triboactive from Krasnoyarsk Institute of chemistry and chemical technology, Krasnoyarsk Institute of Biophysics together with "RealDzerjinsk", as well as the results of the development of the new triboactive based on nano carbon fi bers. It is proved that in contrast to pure nanodiamond powders imported nanomaterials explosion technologies graphite represent pseudoalpina nanoparticles surrounded by a carbon shell. Saturating them various peripheral organic compounds can be sedimentary stable carbon clusters, working at friction in oil is not for mechanism sergiovanni, and the mechanism of chemisorption and polymerization components triborate. A new, more technologically advanced and cheaper tribological material GRAF SB on the basis of on nano carbon fi bers, are no less eff ective nanodiamond, only works on mechamechanism of adsorption and chemisorption.
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Dimitrov, Nikolay. "(Electrodeposition Division Research Award) Impact of Electrodeposition on the Design and Synthesis of Nanoporous Functional Materials." ECS Meeting Abstracts MA2022-02, no. 24 (October 9, 2022): 1006. http://dx.doi.org/10.1149/ma2022-02241006mtgabs.
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The sustainable growth of efficient and durable functional nanomaterials applicable in a variety of practical fields is founded on the creative design, rational synthesis, extensive characterization, and realistic testing of products developed by countless hard-working research teams. Many of these nanomaterials must include high-cost and scarcely distributed elements and compounds that need to be either eliminated or minimally used as much as it is possible. Most commonly, such minimization has been approached by synthesizing the materials of interest in the form of nanoparticles. Nanoparticles are undoubtedly superior to other type of materials in a variety of fields and applications because of their large surface area to volume ratio and unique chemical and physical properties. Their implementation in practice also addresses well the objective for minimization of the use of expensive elements and compounds. At the same time, as class of nanomaterilas, the nanopartiles suffer some drawbacks like loss of material during synthesis, surface contamination/blockage by chemicals used in their synthesis, mechanical disconnection from carrier electrodes, and / or aggregation during exploitation. Such unwelcome developments often make it difficult to keep the cost low and/or lead to a reduction of the active surface area and thus, to loss of functionality, performance, and stability. A way of addressing some of the mentioned shortcomings is to employ electrochemical approaches for synthesizing alternative nanostructured materials directly on the carrier electrode. Such approach not only provides for better adhesion and contamination free surface, but also enables an efficient control of the amount of the deposited material along with flexibility in the structuring during the material synthesis, thus most-certainly reducing its overall cost of the final product. The electrochemical means inevitably include controlled electrodeposition of a binary / ternary alloy layer with a desired thickness and pre-selected elemental composition. A naturally following step in the material's synthesis is the selective oxidative dissolution of the less / least noble metal (a.k.a. de-alloying) to create a continuous nanoporous film with tunable pore and ligament size comprising a length-scale in the single-digit nanometer range. Finally, as-synthesized nanostructured films may either be employed directly for the purposes of the intended applications or be subjected to an additional surface functionalization by a further electrodeposition or electroless of a thin layer with specific properties that is aimed at boosting the material's functionality, performance and stability. This talk will introduce the use of electrochemical means in the design and synthesis of continuous nanoporous Au- and Cu-based functional alloy nanomaterials with applications in electrocatalysis, environmental protection, and electronic packaging. The discussed synthetic approaches will include bulk alloy electrodeposition, electrochemical de-alloying, and electrochemical atomic layer deposition for surface functionalization by films with a thickness in the range from a sub-monolayer to a few monolayers. The presentation of each class of nanostructured materials of interest to this talk will include a conceptual description of their synthetic routines, followed by an electrochemical and ultra-high vacuum-based characterization results, and concluded with a glimpse into the outcome of standard performance tests of the functionality, performance, and stability of said materials in intended applications. Finally, aspects of the materials performance associated with hypothesized mechanistic views will be critically discussed in comparison with other nanoparticulate and/or nanostructured counterpart materials in the literature.
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Hawi, Sara, Somayeh Gharavian, Marek Burda, Saurav Goel, Saeid Lotfian, Tasnuva Khaleque, and Hamed Yazdani Nezhad. "Development of carbonaceous tin-based solder composite achieving unprecedented joint performance." Emergent Materials 4, no. 6 (December 2021): 1679–96. http://dx.doi.org/10.1007/s42247-021-00337-9.
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AbstractWeight reduction and improved strength are two common engineering goals in the joining sector to benefit transport, aerospace, and nuclear industries amongst others. Here, in this paper, we show that the suitable addition of carbon nanomaterials to a tin-based solder material matrix (C-Solder® supplied by Cametics Ltd.) results in two-fold strength of soldered composite joints. Single-lap shear joint experiments were conducted on soldered aluminium alloy (6082 T6) substrates. The soldering material was reinforced in different mix ratios by carbon black, graphene, and single-walled carbon nanotubes (SWCNT) and benchmarked against the pristine C-solder®. The material characterisation was performed using Vickers micro-indentation, differential scanning calorimetry and nano-indentation, whereas functional testing involved mechanical shear tests using single-lap aluminium soldered joints and creep tests. The hardness was observed to improve in all cases except for the 0.01 wt.% graphene reinforced solders, with 5% and 4% improvements in 0.05 carbon black and SWCNT reinforced solders, respectively. The maximum creep indentation was noted to improve for all solder categories with maximum 11% and 8% improvements in 0.05 wt.% carbon black and SWCNT reinforced ones. In general, the 0.05 wt.% nanomaterial reinforced solders promoted progressive cohesion failure in the joints as opposed to instantaneous fully de-bonded failure observed in pristine soldered joints, which suggests potential application in high-performance structures where no service load induced adhesion failure is permissible (e.g. aerospace assemblies). The novel innovation developed here will pave the way to achieving high-performance solder joining without carrying out extensive surface preparations.
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Luo, Qi, and Hua Li. "Antibiotics in livestock wastewater treatment by using biomass-derived activated carbon supported ZnS nanomaterials." Water Science and Technology 80, no. 7 (October 1, 2019): 1367–73. http://dx.doi.org/10.2166/wst.2019.382.
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Abstract A new type of composite photocatalyst material was successfully prepared through the ultrasound-assisted coprecipitation method precipitate of zinc sulfide (ZnS) nanomaterials on peach wood activated carbon (PAC). The optimization of ZnS@PAC demonstrates excellent photocatalytic performance by using the response surface method (RSM), which is essential for improving photocatalytic performance. In this model it was found that the photocatalytic degradation of enrofloxacin (ENR) increased with microwave heating power and ZnS concentration, whereas it decreased with increasing activation time. The RSM model predicts that under certain conditions (microwave heating power 800 W, activation time 3 h, ZnS 0.5 mol·L−1), the maximum degradation rate of ENR in livestock and poultry wastewater is 97.81%. By empirical testing under the optimum conditions with 97.35% degradation the accuracy of the designed model was proven using RSM and the mechanism of the photocatalytic process was studied.
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Vallejos, Stella, Isabel Gràcia, Eduardo Figueras, and Carles Cané. "Catalyst-Free Vapor-Phase Method for Direct Integration of Gas Sensing Nanostructures with Polymeric Transducing Platforms." Journal of Nanomaterials 2014 (2014): 1–9. http://dx.doi.org/10.1155/2014/932129.
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Tungsten oxide nanoneedles (NNs) are grown and integrated directly with polymeric transducing platforms for gas sensors via aerosol-assisted chemical vapor deposition (AACVD) method. Material analysis shows the feasibility to grow highly crystalline nanomaterials in the form of NNs with aspect ratios between 80 and 200 and with high concentration of oxygen vacancies at the surface, whereas gas testing demonstrates moderate sensing responses to hydrogen at concentrations between 10 ppm and 50 ppm, which are comparable with results for tungsten oxide NNs grown on silicon transducing platforms. This method is demonstrated to be an attractive route to fabricate next generation of gas sensors devices, provided with flexibility and functionality, with great potential in a cost effective production for large-scale applications.
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Pavlicek, Anna, Florian Part, Sabine Gressler, Gloria Rose, André Gazsó, Eva-Kathrin Ehmoser, and Marion Huber-Humer. "Testing the Applicability of the Safe-by-Design Concept: A Theoretical Case Study Using Polymer Nanoclay Composites for Coffee Capsules." Sustainability 13, no. 24 (December 17, 2021): 13951. http://dx.doi.org/10.3390/su132413951.
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The production and use of engineered nanomaterials and nano-enabled products is increasing, enabling innovations in many application areas, e.g., in the sector of food contact materials. However, nanosafety-relevant information for chemical risk assessment is still scarce, leading to a high level of uncertainty and making the early integration of safety to the innovation process indispensable. This study analyzed the strengths, weaknesses, and applicability of the nano-specific Safe-by-Design (SbD) concept using nanoclay-containing polymer coffee capsules as a theoretical case study. In addition, a material flow analysis was conducted to identify exposure pathways and potential risks, and a multi-stakeholder approach was applied to discursively discuss challenges when attempting to combine safety and innovation at an early stage. The results indicate that the SbD concept is generally welcomed by all stakeholders, but there is a lack of clear rules on the transfer of information between the actors involved. Furthermore, a voluntary, practical application usually requires in-depth knowledge of nanotechnology and often additional financial efforts. Therefore, incentives need to be created, as there is currently no obvious added value from a company’s point of view. The SbD concept should be further developed, standardized, and integrated into existing legal frameworks to be implemented effectively.
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Mechi, Sumeia A., Muhannad Al-Waily, and Aseel Al-Khatat. "The Mechanical Properties of the Lower Limb Socket Material Using Natural Fibers: A Review." Materials Science Forum 1039 (July 20, 2021): 473–92. http://dx.doi.org/10.4028/www.scientific.net/msf.1039.473.
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In general, the lower prosthesis consists of socket, leg, ankle, and foot. The socket is the crucial part for connecting the remaining part of the limb and the prosthesis, as it is essential to distribute the load to the amputation patient to provide comfort and add to the proper appearance of the amputation patient. A research that was included methods of manufacturing it, choosing the composite materials necessary for the design, higher durability, lighter weight, and less cost. Previous research used polymer composites reinforced with fibers as glass fibers, carbon fiber, and Kevlar. Other researchers have studied natural fibers' use as reinforcement fiber by mixing resin materials or adding nanomaterials to modify the mechanical properties and reduce costs. After calculating performing the required mechanical tests such as tensile, fatigue, and impact testing, the required properties of the composite material are found, where the prosthesis socket is manufactured below the knee with the application of different loads of the socket. A review of socket models used in developing countries was performed with regard to design, modeling, and finite element analysis (FEA). This review aims to study the material's behavior and mechanical properties by using natural fibers for manufacturing prosthetic sockets. The review discusses the socket manufacture methods proposed to develop the socket industry based on natural fibers to reduce the hot and humid environment using Kenaf and other natural fibers.
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Gabidinova, Gulnaz Faezovna, Gyuzel Abdulkhalimovna Timerbulatova, and Liliya Minvagizovna Fatkhutdinova. "Principles for assessing the genotoxicity of carbon nanomaterials in vitro (on the example of carbon nanotubes) (literature review)." Toxicological Review 29, no. 6 (December 30, 2021): 16–23. http://dx.doi.org/10.36946/0869-7922-2021-29-6-16-23.
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Introduction. Genotoxicity of nanomaterials (NM) is becoming a major concern when investigating new NM for their safety. Each mutagen is considered to be potentially carcinogenic, therefore a genotoxicity assessment is necessary. However, a clear strategy for assessing the genotoxic effect of NM has not yet been developed. Material and methods. The material for the analysis have included literature sources from the bibliographic databases PubMed, Scopus, RSCI. Results. Physicochemical characterization of NM is carried out using high-resolution microscopic and light scattering methods. Before testing for genotoxicity, it is necessary to know the cytotoxicity of the tested NM in order to select the appropriate concentration range. The most important and significant tests are based on the cell viability. MTT assay is a colorimetric test that evaluates the metabolic activity of cells. In addition, viability can be determined using microscopy, flow cytometry, determination of lactate dehydrogenase. Genotoxicity evaluation can be carried out only after the preliminary steps. The strategy should include genotoxicity endpoints: DNA damage, gene mutations, chromosomal damage. The in vitro mammalian gene mutation test, usually performed using mouse lymphoma cells, detects a wide range of genetic damage, including gene deletions. The most common test for detecting chromosomal damage is an in vitro micronucleus assay. DNA strand breaks are most often assessed using the comet DNA assay. Conclusion. Compulsory stages in the study of the genotoxicity of nanomaterials should be preliminary studies, including physicochemical characterization and assessment of cytotoxicity, as well as the study of the endpoints of genotoxicity and potential mechanisms.
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G, Baranov, Komisarenko O, and Prohorenko O. "INFOLOGICAL MODELING TECHNOLOGY PROCESSES OF PERSPECTIVE FOLDED MATERIALS." National Transport University Bulletin 1, no. 46 (2020): 21–34. http://dx.doi.org/10.33744/2308-6645-2020-1-46-021-034.
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The article is devoted to the development of methods infolohichnoho modeling and simulation polierhatychnoho documentary describing the test bearing properties nanomaterials that determine the 33 endurance and technological resources mixtures structural components pavement layers in terms the variety effects to cover non-stationary environment and traffic. Formalized mathematical description models and methods necessary for the system CM-PD as hardware and software testing technology polierhatychnoho structure formation nanomaterials under technical and technological orders endurance performance evaluation and resource material layers work surfaces for safe movement traffic forecasting. The peculiarities the modes interaction and the language simulation ergatic modeling for the search rational technologies creation road materials are substantiated. The proposed analytical tools aimed at forming the structure silicon-carbon polymers and composites with expected force-moment and mass-energy physicochemical properties to counteract the effects heterogeneous factors non-stationary environment. The method infological modeling processes for providing conditions for the purposeful between atomic and molecular interactions in the limited local spatial volumes is developed. Formalized parametrization of mutual functions distribution concentrations, pressure and temperatures, which jointly accelerates the stage thermodynamic self-organization and controlledly form the domain-granular structures substances artificial structural materials (SCM) road cover. The information analytical tools the KM-PD system provide the reliability the estimates endurance interval, mechanical strength, integrated resource, obtained by the methods simulation the MSC and in general, KSSSDO. Mixtures substances withstand similar effects from environmental factors and respond equally to microphase spatial separation compatible component components. The maximum levels energy efficiency ordered load bearing coverings are the achievement for the operation the transport and road complex with non-stationary flows moving objects on the surfaces the future ITS infrastructure provided by the agreed levels multiple heterogeneous interactions. KEY WORDS: THERMODYNAMIC SYNTHESIS, FORMATION OF NANOSTRUCTURES, DOCUMENTARIES DECISION, INFORMATION TECHNOLOGY, INFOLOHICHNE MODELING, CARRYING LAYERS TRANSPORT INTERACTION CRITERION SIMILARITY SECURITY RESOURCE SPACE SELF-ORGANIZATION.
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I, Borets, Sokolova O, Soloviova O, and Vysotska I. "ORGANIZATION OF THE MULTIMODAL TRANSPORTATION OF THE GOODS ON THE AIR TRANSPORT." National Transport University Bulletin 1, no. 46 (2020): 35–44. http://dx.doi.org/10.33744/2308-6645-2020-1-46-035-044.
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The article is devoted to the development of methods infolohichnoho modeling and simulation polierhatychnoho documentary describing the test bearing properties nanomaterials that determine the endurance and technological resources mixtures structural components pavement layers in terms the variety effects to cover non-stationary environment and traffic. Formalized mathematical description models and methods necessary for the system CM-PD as hardware and software testing technology polierhatychnoho structure formation nanomaterials under technical and technological orders endurance performance evaluation and resource material layers work surfaces for safe movement traffic forecasting. The peculiarities the modes interaction and the language simulation ergatic modeling for the search rational technologies creation road materials are substantiated. The proposed analytical tools aimed at forming the structure silicon-carbon polymers and composites with expected force-moment and mass-energy physicochemical properties to counteract the effects heterogeneous factors non-stationary environment. The method infological modeling processes for providing conditions for the purposeful between atomic and molecular interactions in the limited local spatial volumes is developed. Formalized parametrization of mutual functions distribution concentrations, pressure and temperatures, which jointly accelerates the stage thermodynamic self-organization and controlledly form the domain-granular structures substances artificial structural materials (SCM) road cover. The information analytical tools the KM-PD system provide the reliability the estimates endurance interval, mechanical strength, integrated resource, obtained by the methods simulation the MSC and in general, KSSSDO. Mixtures substances withstand similar effects from environmental factors and respond equally to microphase spatial separation compatible component components. The maximum levels energy efficiency ordered load bearing coverings are the achievement for the operation the transport and road complex with non-stationary flows moving objects on the surfaces the future ITS infrastructure provided by the agreed levels multiple heterogeneous interactions. KEY WORDS: THERMODYNAMIC SYNTHESIS, FORMATION OF NANOSTRUCTURES, DOCUMENTARIES DECISION, INFORMATION TECHNOLOGY, INFOLOHICHNE MODELING, CARRYING LAYERS TRANSPORT INTERACTION CRITERION SIMILARITY SECURITY RESOURCE SPACE SELF-ORGANIZATION.
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Perez-Ema, Natalia, and Monica Alvarez de Buergo. "Evaluation of Multi-Functional Silica-Based Nano-Products for Consolidating and Protecting Stone Material from Archaeological Sites." Solid State Phenomena 286 (January 2019): 95–104. http://dx.doi.org/10.4028/www.scientific.net/ssp.286.95.
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A silica-based nanoproduct - UCAT-10P© - developed and patented by the TEP-243 (Molecular sieves and other nanomaterials) group of the Cadiz University (UCA) is applied on two stone materials – granite and marble – from the stage front of the Roman theater of Merida, World Heritage by UNESCO (1993). Marble shows firstly scaling as the main decay form, and granite, grain-disintegration, which, at the same time, favor an acceleration of their deterioration condition due to physical, mechanical, chemical and biological processes. That is the reason of assessing the efficiency and durability of a multifuncional nanoproduct, with both consolidating and hydrophobing effects. The performance of this product has been evaluated in terms of the appearance of the stone surfaces (color and roughness), the consolidating role (hardness and ultrasound velocity) and the hydrophobing achievements (capillarity and water contact angle). The most distinctive feature of this research is the in situ testing of the stone blocks, the use of mostly non-destructive and portable techniques, and the monitoring of the product performance of the treatment at a short (1 month) and mid-term (12-15 months), proving the efficacy of the product, although its behavior changes with time.
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Chouhan, Raghuraj Singh, Maitri Shah, Drishya Prakashan, Ramya P R, Pratik Kolhe, and Sonu Gandhi. "Emerging Trends and Recent Progress of MXene as a Promising 2D Material for Point of Care (POC) Diagnostics." Diagnostics 13, no. 4 (February 12, 2023): 697. http://dx.doi.org/10.3390/diagnostics13040697.
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Two-dimensional (2D) nanomaterials with chemical and structural diversity have piqued the interest of the scientific community due to their superior photonic, mechanical, electrical, magnetic, and catalytic capabilities that distinguish them from their bulk counterparts. Among these 2D materials, two-dimensional (2D) transition metal carbides, carbonitrides, and nitrides with a general chemical formula of Mn+1XnTx (where n = 1–3), together known as MXenes, have gained tremendous popularity and demonstrated competitive performance in biosensing applications. In this review, we focus on the cutting-edge advances in MXene-related biomaterials, with a systematic summary on their design, synthesis, surface engineering approaches, unique properties, and biological properties. We particularly emphasize the property–activity–effect relationship of MXenes at the nano–bio interface. We also discuss the recent trends in the application of MXenes in accelerating the performance of conventional point of care (POC) devices towards more practical approaches as the next generation of POC tools. Finally, we explore in depth the existing problems, challenges, and potential for future improvement of MXene-based materials for POC testing, with the goal of facilitating their early realization of biological applications.
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Suryakala, K., and R. Venckatesh. "Synthesis of Nano-Crystalline LiNdxMn2-xO4Powder by Novel Cam-Microwave Assisted Sol-Gel Method." E-Journal of Chemistry 4, no. 4 (2007): 487–95. http://dx.doi.org/10.1155/2007/123132.
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With the advancement of nanotechnology, there is an interest in the replacement of conventional materials by nanomaterials. There is a reasonable chance that as the active mass of electrode for lithium batteries is comprised of smaller particles, they will perform better in terms of capacity, power, rate capability and stability. LiMn2O4is inexpensive material but it shows rather poor cyclic performance. The electrochemical performance of spinel type LiMn2O4has been effectively improved with doping of Nd the “bottom–up” approach of LiMn2O4and LiNdxMn2-xO4(x = 0.1, 0.2, 0.3 and 0.4) synthesized by citric acid modified microwave assisted sol-gel method. LiMn2O4has been synthesized from nitrates and acetates. Citric acid was added as a complexing agent and acryl amide acts as a gelling agent. This technique offers better homogeneity, preferred surface morphology, reduced heat-treatment conditions, sub-micron sized particles and better crystallinity. The structure and the electrochemical performances of the samples are characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, cyclic voltammetry and charge-discharge testing. XRD data shows both samples exhibit the same pure spinel phase. Nano crystalline LiNd0.3Mn1.7O4sample has a smaller morphology including small particle size and the homogeneous particle distribution compared to the other compositions.
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Tao, N., X. Li, and Jin Ping Lu. "Recent Development and Application of Polymers in Concrete Technology in Singapore." Advanced Materials Research 1129 (November 2015): 102–12. http://dx.doi.org/10.4028/www.scientific.net/amr.1129.102.
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Polymer has been extensively used in construction in Singapore during the past few decades and has become a necessary component of some building materials including polymer modified cement mortar, epoxy or Polyurethane (PU) floor screed and injection materials, and fiber-reinforced plastic (FRP) materials. Compare with conventional concrete, polymer concrete composites may achieve remarkable advantages, such as high tension, high flexural strength, high ductility, ability to absorb energy, and high resistance to chemical attack, corrosion, freezing and thawing, and consequently gain more research interest for the scientific community. There are numerous possibilities for incorporation of these materials, such as latex, natural resources, fibers, nanomaterials and laminates. The presence of polymer makes it suitable for wide applications. The various categories of polymer concrete composites are widely used in Singapore’s public and private projects. To ensure and maintain the high standards of the building quality, independent testing and inspection plays a very important role. The present paper reviews recent research and development activities, and applications of polymer concrete composites in Singapore. The innovations and new approaches are reviewed. The development of the requirements and specifications for various polymer concrete composite products are described and discussed. The effect of different factors on the polymer concrete composite and material selection are also described. In addition, the paper also outlines the methods and measures used to inspect and control the quality of application.
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Pingale, Ajay D., Diplesh Gautam, Ayush Owhal, Dhruv Deshwal, Sachin U. Belgamwar, and Venkatesh K. P. Rao. "Development of Non-Destructive Dynamic Characterization Technique for MMCs: Predictions of Mechanical Properties for Al@Al2O3 Composites." NDT 1, no. 1 (July 31, 2023): 22–34. http://dx.doi.org/10.3390/ndt1010003.
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In the past several decades, many destructive and non-destructive testing techniques have been developed to evaluate the characteristics of metal matrix composites (MMCs). This research aims to calculate the mechanical properties of the Al@Al2O3 composites by varying alumina nanoparticles (Al2O3 NPs) content using a non-invasive, position sensing detector (PSD) unit-based optical method. The composite was prepared by a powder metallurgy technique, and its characterization was conducted using SEM and XRD to understand its surface morphology and microstructure. The natural frequency and Young’s modulus of the composite were estimated experimentally. Young’s modulus was calculated using this natural frequency. The proposed study shows that Young’s modulus of the composite increases with an increase in Al2O3 NPs content in the composition, irrespective of the testing method. Along with this, natural frequency also increases with the increase in the Al2O3 NPs content. Evaluated properties were compared with the numerical modeling using COMSOL Multiphysics. The experimental and numerical results are equivalent and within the margin of error. This study illustrates the development of an experimental approach for evaluating the mechanical properties of a composite material. This experimental approach can be used whenever sample dimension and space are constrained to evaluate the mechanical behavior of nanomaterials and nanocomposites.
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Fernandes, Cristina I., Pedro D. Vaz, and Carla D. Nunes. "Selective and Efficient Olefin Epoxidation by Robust Magnetic Mo Nanocatalysts." Catalysts 11, no. 3 (March 15, 2021): 380. http://dx.doi.org/10.3390/catal11030380.
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Iron oxide magnetic nanoparticles were synthesized with different sizes (11 and 30 nm). Subsequently they were shelled with a silica layer allowing grafting of an organic phosphine ligand that coordinated to the [MoI2(CO)3] organometallic core. The silica layer was prepared by the Stöber method using either mechanical (both 11 and 30 nm nanoparticles) or ultrasound (30 nm only) stirring. The latter nanoparticles once coated with silica were obtained with less aggregation, which was beneficial for the final material holding the organometallic moiety. The Mo loadings were found to be 0.20, 0.18, and 0.34 mmolMo·g−1 for MNP30-Si-phos-Mo,MNP11-Si-phos-Mo, and MNP30-Sius-phos-Mo, respectively, with the ligand-to-metal ratio reaching 4.6, 4.8, and 3.2, by the same order, confirming coordination of the Mo moieties to two phos ligands. Structural characterization obtained from powder X-ray diffraction (XRD), scanning electron microscopy (SEM)/ transmission electron microscopy (TEM) analysis, and Fourier-transform infrared (FTIR) spectroscopy data confirmed the successful synthesis of all nanomaterials. Olefin epoxidation of several substrates catalyzed by these organometallic nano-hybrid materials using tert-butyl hydroperoxide (tbhp) as oxidant, achieved very good results. Extensive testing of the catalysts showed that they are highly active, selective, recyclable, and efficient concerning oxidant consumption.
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Volcheck, V. S., and V. R. Stempitsky. "Numerical simulation of the sensor for toxic nanoparticles based on the heterostructure field effect transistor." Doklady BGUIR 18, no. 8 (December 27, 2020): 62–68. http://dx.doi.org/10.35596/1729-7648-2020-18-8-62-68.
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A significant rise in the mass production of products that contain nanoparticles is of growing concern due to the detection of their toxic effects on living organisms. The standard method for analyzing the toxicity of substances, including nanomaterials, is toxicological testing, which requires the substantial consumption of time and material resources. An alternative approach is to develop models that predict the effect of nanomaterials on biological systems. In both cases, for the detection of nanoparticles an effective electronic complex consisting of a sensor with high sensitivity and a data reception/processing/transmission system is necessary. In recent times, fundamental and applied research activities aimed at the application of heterostructure field-effect transistors – high electron mobility transistors–as a base for such sensors have been undertaken. The purpose of this work is to develop a technique for modeling a sensor for toxic nanoparticles based on the heterostructure field-effect transistor. The object of the research is a gallium nitride high electron mobility transistor device structure. The subject of the research is the electrical characteristics of the transistor obtained in static mode. The calculation results show that the dependence between the concentration of the toxic nanoparticles in the test medium and the polarization charge surface density could serve as a base for modeling the sensor for toxic nanoparticles based on the heterostructure field-effect transistor. The primary advantage of the proposed technique is the use of the scaling parameter intended directly for calibrating the polarization charge density in accordance with the two-dimensional electron gas concentration. The obtained results can be utilized by the electronics industry of the Republic of Belarus for developing the hardware components of gallium nitride high-frequency electronics.
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Vogt, Annika, Fiorenza Rancan, Sebastian Ahlberg, Berouz Nazemi, Chun Sik Choe, Maxim E. Darvin, Sabrina Hadam, et al. "Interaction of dermatologically relevant nanoparticles with skin cells and skin." Beilstein Journal of Nanotechnology 5 (December 8, 2014): 2363–73. http://dx.doi.org/10.3762/bjnano.5.245.
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The investigation of nanoparticle interactions with tissues is complex. High levels of standardization, ideally testing of different material types in the same biological model, and combinations of sensitive imaging and detection methods are required. Here, we present our studies on nanoparticle interactions with skin, skin cells, and biological media. Silica, titanium dioxide and silver particles were chosen as representative examples for different types of skin exposure to nanomaterials, e.g., unintended environmental exposure (silica) versus intended exposure through application of sunscreen (titanium dioxide) or antiseptics (silver). Because each particle type exhibits specific physicochemical properties, we were able to apply different combinations of methods to examine skin penetration and cellular uptake, including optical microscopy, electron microscopy, X-ray microscopy on cells and tissue sections, flow cytometry of isolated skin cells as well as Raman microscopy on whole tissue blocks. In order to assess the biological relevance of such findings, cell viability and free radical production were monitored on cells and in whole tissue samples. The combination of technologies and the joint discussion of results enabled us to look at nanoparticle–skin interactions and the biological relevance of our findings from different angles.
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Lencova, Simona, Kamila Zdenkova, Vera Jencova, Katerina Demnerova, Klara Zemanova, Radka Kolackova, Kristyna Hozdova, and Hana Stiborova. "Benefits of Polyamide Nanofibrous Materials: Antibacterial Activity and Retention Ability for Staphylococcus Aureus." Nanomaterials 11, no. 2 (February 13, 2021): 480. http://dx.doi.org/10.3390/nano11020480.
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Although nanomaterials are used in many fields, little is known about the fundamental interactions between nanomaterials and microorganisms. To test antimicrobial properties and retention ability, 13 electrospun polyamide (PA) nanomaterials with different morphology and functionalization with various concentrations of AgNO3 and chlorhexidine (CHX) were analyzed. Staphylococcus aureus CCM 4516 was used to verify the designed nanomaterials’ inhibition and permeability assays. All functionalized PAs suppressed bacterial growth, and the most effective antimicrobial nanomaterial was evaluated to be PA 12% with 4.0 wt% CHX (inhibition zones: 2.9 ± 0.2 mm; log10 suppression: 8.9 ± 0.0; inhibitory rate: 100.0%). Furthermore, the long-term stability of all functionalized PAs was tested. These nanomaterials can be stored at least nine months after their preparation without losing their antibacterial effect. A filtration apparatus was constructed for testing the retention of PAs. All of the PAs effectively retained the filtered bacteria with log10 removal of 3.3–6.8 and a retention rate of 96.7–100.0%. Surface density significantly influenced the retention efficiency of PAs (p ≤ 0.01), while the effect of fiber diameter was not confirmed (p ≥ 0.05). Due to their stability, retention, and antimicrobial properties, they can serve as a model for medical or filtration applications.
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Awasthi, Sakshi, and Jai Gopal Sharma. "Toxicity and Challenges of Nanomaterials and Their Impact on the Environment." Nature Environment and Pollution Technology 21, no. 2 (June 1, 2022): 643–50. http://dx.doi.org/10.46488/nept.2022.v21i02.023.
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Nanomaterials (NMs) are those tiny materials that range from 1-100 nm. These materials show different characteristics in their physical and chemical forms in comparison to their bulk form. The use of nanomaterials is increasing day by day because of their enormous capabilities in the health sector as well as in other industries. There are currently few, if any, actual protocols for the disposal and characterization of these nanomaterials, which results in environmental toxicity. Heavy use of chemicals in the testing of nanomaterials has resulted in polluting our entire ecosystem. Inconsistent results of nanomaterial show that it is challenging to reduce the toxicity generated by it. In this review, we discuss the administration and use of nanomaterials in the agribusiness sector, in food, and, most importantly, in the environment, for purposes of protecting our plants and crops, dealing with incurable diseases, developing new tastes and textures in the food sector, sensations, identifying pathogenic organisms, and distribution systems where these minute particles can wreak havoc. Despite the potential benefits of nanomaterials, their unintentional harm to the environment and, in some cases, our health is making further development difficult. This article discusses the toxicity of nanomaterials and how they damage our environment, as well as the obstacles that come with overcoming them.
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Saleem, Haleema, and Syed Javaid Zaidi. "Recent Developments in the Application of Nanomaterials in Agroecosystems." Nanomaterials 10, no. 12 (December 2, 2020): 2411. http://dx.doi.org/10.3390/nano10122411.
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Nanotechnology implies the scientific research, development, and manufacture, along with processing, of materials and structures on a nano scale. Presently, the contamination of metalloids and metals in the soil has gained substantial attention. The consolidation of nanomaterials and plants in ecological management has received considerable research attention because certain nanomaterials could enhance plant seed germination and entire plant growth. Conversely, when the nanomaterial concentration is not properly controlled, toxicity will definitely develop. This paper discusses the role of nanomaterials as: (1) nano-pesticides (for improving the plant resistance against the biotic stress); and (2) nano-fertilizers (for promoting the plant growth by providing vital nutrients). This review analyzes the potential usages of nanomaterials in agroecosystem. In addition, the adverse effects of nanomaterials on soil organisms are discussed. We mostly examine the beneficial effects of nanomaterials such as nano-zerovalent iron, iron oxide, titanium dioxide, nano-hydroxyapatite, carbon nanotubes, and silver- and copper-based nanomaterials. Some nanomaterials can affect the growth, survival, and reproduction of soil organisms. A change from testing/using nanomaterials in plants for developing nanomaterials depending on agricultural requirements would be an important phase in the utilization of nanomaterials in sustainable agriculture. Conversely, the transport as well as ecological toxicity of nanomaterials should be seriously examined for guaranteeing its benign usage in agriculture.
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Bhalerao, Vrushali Yogesh, and Sanjay Shridhar Lakade. "Enhancement of Tribological Properties of Cubic and Hexagonal Boron Nitride Nanoparticles Impregnated on Bearing Steel via Vacuum Heat Treatment Method." Coatings 12, no. 12 (December 9, 2022): 1940. http://dx.doi.org/10.3390/coatings12121940.
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In the current world of coatings and nanomaterials, specifically bearings, zinc, chromium, nickel, diamond-like coatings, and molybdenum disulfide are being used, to name but a few. Boron nitride in various forms has been used to enhance the surface properties, such as hardness, wear resistance, and corrosion resistance of dies, tools, etc. In this paper, a significant focus is being given to the improvement of the surface properties of bearing-steel materials by the impregnation of cubic and hexagonal boron nitride nanoparticles. The vacuum heat treatment method is used for treating the sample pins of material equivalents to EN31. In the design of the experiments, the Taguchi method with L27 orthogonal array is used for the optimization of various parameters, such as the weight % of c-BN and h-BN nanoparticles and the temperature of the vacuum treatment. With the help of preliminary experimentation, the three levels of three parameters are decided. The microhardness analysis shows an improvement from 321 HV0.1 to 766 HV0.1 for a 50 µm case depth of nanoparticle impregnation. The evaluation of the influence of selected factors is also performed using ANOVA and the S/N ratio, and it was revealed that hex boron nitride (h-BN) affects the microhardness value more than the other two factors. The friction and wear testing reveal that the wear properties are improved by approximately 1.6 times, and the frictional force also decreases by approx. 1.4 times. Scanning electron microscope (SEM) analysis shows that the nanoparticles are penetrated by 21.09% and 46.99% atomic weight. In addition, a reduction in the friction coefficient and better wear response were achieved as a result of the heat treatment with nanoparticle impregnation.
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Shaban, Mahmoud, Mohammed F. Alsharekh, Fahad Nasser Alsunaydih, Abdulrahman I. Alateyah, Majed O. Alawad, Amal BaQais, Mokhtar Kamel, Ahmed Nassef, Medhat A. El-Hadek, and Waleed H. El-Garaihy. "Investigation of the Effect of ECAP Parameters on Hardness, Tensile Properties, Impact Toughness, and Electrical Conductivity of Pure Cu through Machine Learning Predictive Models." Materials 15, no. 24 (December 17, 2022): 9032. http://dx.doi.org/10.3390/ma15249032.
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Copper and its related alloys are frequently adopted in contemporary industry due to their outstanding properties, which include mechanical, electrical, and electronic applications. Equal channel angular pressing (ECAP) is a novel method for producing ultrafine-grained or nanomaterials. Modeling material design processes provides exceptionally efficient techniques for minimizing the efforts and time spent on experimental work to manufacture Cu or its associated alloys through the ECAP process. Although there have been various physical-based models, they are frequently coupled with several restrictions and still require significant time and effort to calibrate and enhance their accuracies. Machine learning (ML) techniques that rely primarily on data-driven models are a viable alternative modeling approach that has recently achieved breakthrough achievements. Several ML algorithms were used in the modeling training and testing phases of this work to imitate the influence of ECAP processing parameters on the mechanical and electrical characteristics of pure Cu, including the number of passes (N), ECAP die angle (φ), processing temperature, and route type. Several experiments were conducted on pure commercial Cu while altering the ECAP processing parameters settings. Linear regression, regression trees, ensembles of regression trees, the Gaussian process, support vector regression, and artificial neural networks are the ML algorithms used in this study. Model predictive performance was assessed using metrics such as root-mean-squared errors and R2 scores. The methodologies presented here demonstrated that they could be effectively used to reduce experimental effort and time by reducing the number of experiments runs required to optimize the material attributes aimed at modeling the ECAP conditions for the following performance characteristics: impact toughness (IT), electrical conductivity (EC), hardness, and tensile characteristics of yield strength (σy), ultimate tensile strength (σu), and ductility (Du)
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Jipa, Florin, Stefana Orobeti, Cristian Butnaru, Marian Zamfirescu, Emanuel Axente, Felix Sima, and Koji Sugioka. "Picosecond Laser Processing of Photosensitive Glass for Generation of Biologically Relevant Microenvironments." Applied Sciences 10, no. 24 (December 15, 2020): 8947. http://dx.doi.org/10.3390/app10248947.
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Various material processing techniques have been proposed for fabrication of smart surfaces that can modulate cellular behavior and address specific clinical issues. Among them, laser-based technologies have attracted growing interest due to processing versatility. Latest development of ultrashort pulse lasers with pulse widths from several tens of femtoseconds (fs) to several picoseconds (ps) allows clean microfabrication of a variety of materials at micro- and nanoscale both at surface and in volume. In this study, we addressed the possibility of 3D microfabrication of photosensitive glass (PG) by high repetition rate ps laser-assisted etching (PLAE) to improve the fabrication efficiency for the development of useful tools to be used for specific biological applications. Microfluidic structures fabricated by PLAE should provide the flow aspects, 3D characteristics, and possibility of producing functional structures to achieve the biologically relevant microenvironments. Specifically, the microfluidic structures could induce cellular chemotaxis over extended periods in diffusion-based gradient media. More importantly, the 3D characteristics could reproduce capillaries for in vitro testing of relevant organ models. Single cell trapping and analysis by using the fabricated microfluidic structures are also essential for understanding individual cell behavior within the same population. To this end, this paper demonstrates: (1) generation of 3D structures in glass volume or on surface for fabrication of microfluidic channels, (2) subtractive 3D surface patterning to create patterned molds in a controlled manor for casting polydimethylsiloxane (PDMS) structures and developing single cell microchambers, and (3) designing glass photo-masks to be used for sequel additive patterning of biocompatible nanomaterials with controlled shapes, sizes, and periodicity. Mesenchymal stem cells grown on laser-processed glass surfaces revealed no sign of cytotoxicity, while a collagen thin coating improved cellular adhesion.