Journal articles: 'Exfoliace'

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Chen, I.-Wen P., Yan-Ming Lai, and Wei-Sheng Liao. "One-Pot Synthesis of Chlorophyll-Assisted Exfoliated MoS2/WS2 Heterostructures via Liquid-Phase Exfoliation Method for Photocatalytic Hydrogen Production." Nanomaterials 11, no. 9 (September 18, 2021): 2436. http://dx.doi.org/10.3390/nano11092436.

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Developing strategies for producing hydrogen economically and in greener ways is still an unaccomplished goal. Photoelectrochemical (PEC) water splitting using photoelectrodes under neutral electrolyte conditions provides possibly one of the greenest routes to produce hydrogen. Here, we demonstrate that chlorophyll extracts can be used as an efficient exfoliant to exfoliate bulk MoS2 and WS2 to form a thin layer of a MoS2/WS2 heterostructure. Thin films of solution-processed MoS2 and WS2 nanosheets display photocurrent densities of −1 and −5 mA/cm2, respectively, and hydrogen evolution under simulated solar irradiation. The exfoliated WS2 is significantly more efficient than the exfoliated MoS2; however, the MoS2/WS2 heterostructure results in a 2500% increase in photocurrent densities compared to the individual constituents and over 12 h of PEC durability under a neutral electrolyte. Surprisingly, in real seawater, the MoS2/WS2 heterostructure exhibits stable hydrogen production after solar illumination for 12 h. The synthesis method showed, for the first time, how the MoS2/WS2 heterostructure can be used to produce hydrogen effectively. Our findings highlight the prospects for this heterostructure, which could be coupled with various processes towards improving PEC efficiency and applications.

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Diasio, Matthew A., and David L. Green. "The Effect of Solvent Viscosity on Production of Few-layer Graphene from Liquid-phase Exfoliation of Graphite." MRS Advances 4, no. 3-4 (2019): 241–47. http://dx.doi.org/10.1557/adv.2019.13.

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Abstract:Prior research into the liquid-phase exfoliation of graphite to produce few-layer graphene has focused primarily on the surface energy matching between graphite and solvent; however, the effect of other solvent properties, such as liquid viscosity, have not been systematically explored. In principle, a higher viscosity solvent should enable the production of graphene and other graphitic nanomaterials by liquid-phase exfoliation at lower shear rates than traditionally used organic solvents of low viscosity, such as N-methyl-2-pyrrolidone (NMP). Thus, at a given shear rate, more material should be exfoliated in the higher viscosity solvent. Hence, graphite suspensions in NMP, benzyl benzoate, and propylene glycol were exfoliated at various shear rates in a rheometer. Exfoliant concentrations were measured by ultraviolet- visual (UV-vis) spectroscopy and quality characterization was performed by Raman spectroscopy and scanning electron microscopy (SEM). Graphite exfoliation in the more viscous propylene glycol solvent resulted in a higher exfoliant concentration than in the less viscous NMP and benzyl benzoate solvents across all shear rates. Benzyl benzoate lowered exfoliant levels, likely due to a poor surface energy match, resulting in particle attraction and aggregation. Characterization showed that at least some of our material is few-layer graphene.

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Zhang, Qi, Yulong Zhao, Xin Ma, You Zhao, and Xing Pang. "Study on bonding mechanism of graphene on silicon substrate." Modern Physics Letters B 32, no. 23 (August 17, 2018): 1850265. http://dx.doi.org/10.1142/s0217984918502652.

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The study of bonding mechanism is important for the application of graphene in micro-electro-mechanical system (MEMS). Using molecular dynamics (MD) simulation, the adhesion behavior of graphene on silicon substrate was observed, by applying a constant vertical upward exfoliation velocity to graphene. The effects of silicon substrate size, graphene layer number and exfoliation velocity on adhesion properties of graphene were studied. The minimum velocity to exfoliate monolayer graphene was 4.3 Å/ps, and the maximum adhesive force was 25.04 nN. For two-layer graphene, velocity was applied on the top layer, 5.2 Å/ps and 12 Å/ps were the critical velocities: when the velocity was no more than 5.2 Å/ps, the top layer cannot be exfoliated; as the velocity was in the range of 5.2–12 Å/ps, the second layer was driven upward together with the top layer, because of interlayer interaction between graphene layers; when the velocity increased greater than 12 Å/ps, the top layer graphene was broken through the bonding forces of substrate and the second layer, and exfoliated alone. It can be concluded that the velocity to exfoliate graphene was extremely high, and the adhesion energy was 299.81 mJ/m2 and 323.41 mJ/m2 for exfoliating monolayer and two-layer graphene respectively, thus the adhesive strength between graphene and silicon was very strong.

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Li, Jia Feng, Chen Wen, Jing Ying Bai, Xu Guang Wang, Qing Xin Cui, Xue Zheng Yao, and Li Gong Zhang. "Damage Behavior in Simulated Service Environment of Thermal Control Oxidation Film of 2A12 Alloy." Key Engineering Materials 891 (July 6, 2021): 23–28. http://dx.doi.org/10.4028/www.scientific.net/kem.891.23.

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In order to obtain the service performance of the black anodic oxidation film of 2A12 aluminum alloy, the influence of humidity and temperature in storage environment and heat on the performance of black oxidation film were studied. And the morphologies were analyzed by using optical microscopy (OM) and scanning electron microscopy (SEM). The results showed that after the black anodic oxidation film is produced, "aging" will occur in the natural environment, which can lead to the structure change of the sealing pore and affect the service performance of the film. The film exfoliates off slightly under the humidity of 90%, and the film exfoliates off more seriously when the humidity over 95%. The temperature has a greater influence on the film cracking, especially when the temperature is above 120°C, it is easy to exfoliate off. The exfoliation model was established and the affection mechanism was discussed.

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Rehman, Aafaq ur, Devipriyanka Arepalli, Syed Fakhar Alam, Min-Zy Kim, Jungkyu Choi, and Churl Hee Cho. "Two-Dimensional MFI Zeolite Nanosheets Exfoliated by Surfactant Assisted Solution Process." Nanomaterials 11, no. 9 (September 7, 2021): 2327. http://dx.doi.org/10.3390/nano11092327.

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Two-dimensional (2D) zeolite nanosheets are important for the synthesis of high flux zeolite membranes due to their lateral size in a preferred orientation. A way to obtain 2D zeolite nanosheets is to exfoliate interlocked structures generated during the hydrothermal synthesis. The mechanical and polymer assisted exfoliation process leads to mechanical damage in nanosheets and short lateral size. In the present study, polyvinylpyrrolidone (PVP) was introduced as an exfoliation agent and dispersant, so that multilamellar interlocked silicalite-1 zeolite nanosheets successfully exfoliated into a large lateral size (individual nanosheets 500~1200 nm). The good exfoliation behavior was due to the strong penetration of PVP into multilamellar nanosheets. Sonication assisted by mild milling helps PVP molecules to penetrate through the lamellar structure, contributing to the expansion of the distance between adjacent layers and thus decreasing the interactions between each layer. In addition, the stability of exfoliated nanosheets was evaluated with a series of organic solvents. The exfoliated nanosheets were well dispersed in n-butanol and stable for 30 days. Therefore, the PVP-assisted solution-based exfoliation process provides high aspect ratio MFI zeolite nanosheets in organic solvents for a long period.

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Zhang, Qi, Xing Pang, and Yulong Zhao. "Effect of the External Velocity on the Exfoliation Properties of Graphene from Amorphous SiO2 Surface." Crystals 11, no. 4 (April 20, 2021): 454. http://dx.doi.org/10.3390/cryst11040454.

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External action has a significant influence on the formation of high-quality graphene and the adhesion of graphene on the surface of the MEMS/NEMS device. The atomic-scale simulation and calculation can further study the exfoliation process of graphene by external actions. In multilayer graphene systems where graphene layers were simulated weakly contacted with SiO2 substrate, a constant vertical upward velocity (Vup) was applied to the topmost layer. Then two critical velocities were found, and three kinds of distinct exfoliation processes determined by critical upward velocities were observed in multilayer graphene systems. The first critical velocities are in the range of 0.5 Å/ps–3.18 Å/ps, and the second critical velocities are in the range of 9.5 Å/ps–12.1 Å/ps. When the Vup is less than the first critical velocity, all graphene layers will not be exfoliated. When Vup is between the first and second critical Vup, all layers can be exfoliated almost synchronously at last. When Vup is larger than the second critical Vup, the topmost layer can be exfoliated alone, transferring energy to the underlying layers, and the underlying layers are slowly exfoliated. The maximum exfoliation force to exfoliate the topmost layer of graphene is 3200 times larger than that of all graphene layers. Moreover, it is required 149.26 mJ/m2 to get monolayer graphene from multilayers, while peeling off all layers without effort. This study explains the difficulty to get monolayer graphene and why graphene falls off easily during the transfer process.

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Zhou, Dan, and Jianzhong Yin. "Steer the Rheology of Solvent with Little Surfactant to Exfoliate MoS2 Nanosheet by Liquid Phase Exfoliation Method." Nano 15, no. 10 (October 2020): 2050118. http://dx.doi.org/10.1142/s1793292020501180.

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A surfactant system L64 and alcohol mixture was employed to exfoliate MoS2. To reduce the impact of surfactant on the quality of the nanosheet, the concentration of L64 was decreased to an extremely low value 0.0325 mM. Utilize common ultrasonic bath, the production yield of the nanosheet was increased to about 5% per hour, and statistical results from AFM showed that 40% of the nanosheet were less than 4 nm thick. Rheology characterization showed that surfactant alcohol mixtures were shear thinning fluid, yet the viscosity of L64 system varies directly with the shear rate in the high-speed shear region (higher than 400 s−1), and further affect the shear strength, therefore viscosity at high-speed shear can be considered as an indicator of the effectiveness for the exfoliation system. Exfoliated MoS2 was evaluated by hydrogen evolution reaction, and compared to the bulk MoS2, the 4 wt% Pt/FL-MoS2 improved the overpotential from 366 mV to 273 mV at 10 mA[Formula: see text]cm[Formula: see text]. This study presented a facile and effective route to fabricate 2D MoS2 with much less residue, and bring more opportunities to exploit clean and nontoxic system to exfoliate 2D materials.

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Zhang, Qi, Xin Ma, and Yulong Zhao. "Adhesion Behavior between Multilayer Graphene and Semiconductor Substrates." Applied Sciences 8, no. 11 (November 1, 2018): 2107. http://dx.doi.org/10.3390/app8112107.

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A high bonding strength between graphene and a semiconductor surface is significant to the performance of graphene-based Micro-Electro Mechanical Systems/Nano-Electro Mechanical Systems (MEMS/NEMS) devices. In this paper, by applying a series of constant vertical upward velocities (Vup) to the topmost layer of graphene, the exfoliation processes of multilayer graphene (one to ten layers) from an Si semiconductor substrate were simulated using the molecular dynamics method, and the bonding strength was calculated. The critical exfoliation velocities, adhesion forces, and adhesion energies to exfoliate graphene were obtained. In a system where the number of graphene layers is two or three, there are two critical exfoliation velocities. Graphene cannot be exfoliated when the Vup is lower than the first critical velocity, although the total number of graphene layers can be exfoliated when the Vup is in the range between the first critical velocity and second critical velocity. Only the topmost layer can be exfoliated to be free from the Si surface if the applied Vup is greater than the second critical velocity. In systems where the number of graphene layers is four to ten, only the topmost layer can be free and exfoliated if the exfoliation velocity is greater than the critical velocity. It was found that a relatively low applied Vup resulted in entire graphene layers peeling off from the substrate. The adhesion forces of one-layer to ten-layer graphene systems were in the range of 25.04 nN–74.75 nN, and the adhesion energy levels were in the range of 73.5 mJ/m2–188.45 mJ/m2. These values are consistent with previous experimental results, indicating a reliable bond strength between graphene and Si semiconductor surfaces.

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Ding, Hao, Sana T. Khan, Jingjing Liu, and Luyi Sun. "Gelation Based on Host–Guest Interactions Induced by Multi-Functionalized Nanosheets." Gels 7, no. 3 (August 4, 2021): 106. http://dx.doi.org/10.3390/gels7030106.

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Host–guest interaction, being reversible and stimuli-responsive, is ideal to be applied to the design of hydrogels. We created a gelation system based on the host–guest interactions between the adamantyl groups and β-cyclodextrin (β-CD) polymer. N,N,N-trimethyl-1-adamantylammonium hydroxide (TriMAA) cations were attached to the pre-exfoliated α-zirconium phosphate (α-ZrP) nanosheets by ionic bonding through a displacement reaction with the exfoliating agents. The exfoliated α-ZrP nanosheets with adamantyl groups directly or indirectly attached to the surface act as reversible high-functionality crosslinkers within the β-CD polymer. The gelation occurred at a host-to-guest ratio of 1:10 or 1:5 at room temperature within minutes. The agents used to exfoliate α-ZrP can tailor the surface of the resultant α-ZrP nanosheets and the ionic strength of the system, which directly affects the further gelation results. Plus, the exfoliating agent cations may generate a host-and-guest interaction with the β-CD polymer as well. This gelation process without covalent bonding formation should help fellow researchers to better understand the gelation system and host–guest interactions.

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Lampe, Johanna W., Eunji Kim, Lisa Levy, Laurie A. Davidson, Jennifer S. Goldsby, Fayth L. Miles, Sandi L. Navarro, et al. "Colonic mucosal and exfoliome transcriptomic profiling and fecal microbiome response to a flaxseed lignan extract intervention in humans." American Journal of Clinical Nutrition 110, no. 2 (June 8, 2019): 377–90. http://dx.doi.org/10.1093/ajcn/nqy325.

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ABSTRACTBackgroundMicrobial metabolism of lignans from high-fiber plant foods produces bioactive enterolignans, such as enterolactone (ENL) and enterodiol (END). Enterolignan exposure influences cellular pathways important to cancer risk and is associated with reduced colon tumorigenesis in animal models and lower colorectal cancer risk in humans.ObjectivesThe aim of this study was to test the effects of a flaxseed lignan supplement (50 mg secoisolariciresinol diglucoside/d) compared with placebo on host gene expression in colon biopsies and exfoliated colonocyte RNA in feces and fecal microbial community composition, and to compare responses in relation to ENL excretion.MethodsWe conducted a 2-period randomized, crossover intervention in 42 healthy men and women (20–45 y). We used RNA-seq to measure differentially expressed (DE) genes in colonic mucosa and fecal exfoliated cells through the use of edgeR and functional analysis with Ingenuity Pathway Analysis. We used 16S ribosomal RNA gene (V1–V3) analysis to characterize the fecal microbiome, and measured END and ENL in 24-h urine samples by gas chromatography–mass spectrometry.ResultsWe detected 32 DE genes (false discovery rate <0.05) in the exfoliome, but none in the mucosal biopsies, in response to 60 d of lignan supplement compared with placebo. Statistically significant associations were detected between ENL excretion and fecal microbiome measured at baseline and at the end of the intervention periods. Further, we detected DE genes in colonic mucosa and exfoliome between low- and high-ENL excreters. Analysis of biopsy samples indicated that several anti-inflammatory upstream regulators, including transforming growth factor β and interleukin 10 receptor, were suppressed in low-ENL excreters. Complementary analyses in exfoliated cells also suggested that low-ENL excreters may be predisposed to proinflammatory cellular events due to upregulation of nuclear transcription factor κB and NOS2, and an inhibition of the peroxisome proliferator–activated receptor γ network.ConclusionsThese results suggest that ENL or other activities of the associated gut microbial consortia may modulate response to a dietary lignan intervention. This has important implications for dietary recommendations and chemoprevention strategies. This study was registered at clinicaltrials.gov as NCT01619020.

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Levin, Tzuriel, Yifat Harel, Jean-Paul Lellouche, Alexey Moshkovich, Igor Lapsker, Alex Laikhtman, and Lev Rapoport. "Tungsten Disulfide Inorganic Nanotubes Functionalized by PTFE for Friction Application." Lubricants 9, no. 8 (August 11, 2021): 78. http://dx.doi.org/10.3390/lubricants9080078.

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Inorganic nanotubes (INTs) and fullerene-like nanoparticles (NPs) of WS2/MoS2 penetrate and exfoliate at the contact interface and facilitate tribofilm formation. While the tribological properties are greatly improved by exfoliated NPs that shed easily, they may be diminished by agglomeration in oil. Therefore, surface functionalization is employed to improve dispersion in oil-based suspensions. Here, WS2 INTs were functionalized by polytetrafluoroethylene (PTFE) in a simple and cost-effective bath sonication method. WS2-INTs with two concentrations of added PTFE were characterized by scanning and transmission electron microscopy, micro-Raman spectroscopy, and thermogravimetric analysis. Superior distribution of WS2 was observed before and during friction experiments. Chemical analysis showed a significantly greater amount of PTFE-coated INTs on rubbed surfaces, in accordance with the improved friction and wear properties.

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Zhao, Wenyan, Tao Jiang, Yujie Shan, Hongrui Ding, Junxian Shi, Haibin Chu, and Anhuai Lu. "Direct Exfoliation of Natural SiO2-Containing Molybdenite in Isopropanol: A Cost Efficient Solution for Large-Scale Production of MoS2 Nanosheetes." Nanomaterials 8, no. 10 (October 17, 2018): 843. http://dx.doi.org/10.3390/nano8100843.

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The cost-effective exfoliation of layered materials such as transition metal dichalcogenides into mono- or few- layers is of significant interest for various applications. This paper reports the preparation of few-layered MoS2 from natural SiO2-containing molybdenite by exfoliation in isopropanol (IPA) under mild ultrasonic conditions. One- to six-layer MoS2 nanosheets with dimensions in the range of 50-200 nm are obtained. By contrast, MoS2 quantum dots along with nanosheets are produced using N-methyl-pyrrolidone (NMP) and an aqueous solution of poly (ethylene glycol)-block-poly (propylene glycol)-block-poly (ethylene glycol) (P123) as exfoliation solutions. Compared with molybdenite, commercial bulk MoS2 cannot be exfoliated to nanosheets under the same experimental conditions. In the exfoliation process of the mineral, SiO2 associated in molybdenite plays the role of similar superfine ball milling, which significantly enhances the exfoliation efficiency. This work demonstrates that isopropanol can be used to exfoliate natural molybdenite under mild conditions to produce nanosheets, which facilitates the preparation of highly concentrated MoS2 dispersions or MoS2 in powder form due to the volatility of the solvent. Such exfoliated MoS2 nanosheets exhibit excellent photoconductivity under visible light. Hence, the direct mild exfoliation method of unrefined natural molybdenite provides a solution for low-cost and convenient production of few-layered MoS2 which is appealing for industrial applications.

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Velasteguí López, Efraín, and Anggie Castro Romero. "Plan de negocio para la creación de una Mipymes para elaboración de mascarillas faciales caseras." Visionario Digital 1, no. 1 (January 1, 2017): 49–62. http://dx.doi.org/10.33262/visionariodigital.v1i1.235.

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Será una empresa que se dedique a la elaboración y comercialización de mascarilla 100 por ciento naturales para el rostro, hecho a mano con materiales naturales tanto en los ingredientes utilizados, así como en los envases y etiquetas del producto que son totalmente reciclables. El análisis realizado a este indica que presenta varias oportunidades, las mismas que puede ser aprovechada para que este plan tenga un efectivo desenvolvimiento. Se ha confirmado que algunos clientes tienen atracción y cambios de hábitos de consumo de las personas hacia productos preferencias. La microempresa contara con cinco empleados, cuyas actividades estarán estratégicamente definidas para asegurar la eficiencia en la producción de los productos. Desarrollare las siguientes mascarillas faciales con ingredientes naturales. Para limpiar: avena y yogurt, Para limpiar a profundidad: exfoliante de azúcar, Para desinflamar: café y cocoa, Para relajar: plátano, Para desinfectar: leche de magnesia, Para desinflamar y desinfectar: cebolla y avena, Para relajar: arcilla, Para limpiar y refrescar: pepino, Para regenerar: exfoliante de miel, menta y limón, Para disminuir las arrugas: zanahoria y yogurt, Para hidratar profundamente: aceite de oliva extra virgen, Para exfoliar y rejuvenecer: exfoliante de almendra y miel, Para desinfectar y refrescar: rosas, Para hidratar: aguacate, Para desinflamar y desinfectar: aspirina, Para suavizar e iluminar: papaya, Pará desaparecer los granitos: cilantro, Pará relajar: lavanda, Para retrasar los signos de la edad: miel de maple. Todos y cada uno de estos ingredientes serán utilizados para la limpieza facial en damas y caballeros.

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Treacy, M. M. J., M. E. Bisher, and A. J. Jacobson. "Hollow-cone analysis of intercalated particles in layered H(Ca2Nan-3NbnO3n+1) materials." Proceedings, annual meeting, Electron Microscopy Society of America 51 (August 1, 1993): 748–49. http://dx.doi.org/10.1017/s042482010014957x.

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The series of compounds H(Ca2Nan-3NbnO3n+1) form tetragonal perovskite-related layer structures that are strongly bound in two dimensions, but more weakly bound in the third. These materials can be delaminated by intercalating basic surfactant molecules into the layers, which spontaneously exfoliate the structure to form stable dispersions in a polar solvent. On drying a diluted droplet of this dispersion on an amorphous carbon film supported on a TEM specimen grid, all sheets are observed to lie flat on the carbon, with the thin tetragonal c-axis parallel to the optic axis. Typical sheet dimensions are 1 μm × 1 μm × 1.4 nm. Layered materials prepared in this way make fascinating specimens for transmission electron microscopy because the thickness, composition and orientation are known. Depending on the dispersion density, sheets will occasionally overlap with parallel c axes, but with random relationship between the a axes.Layers of exfoliated H(Ca2Nb3O10) material were examined in a Hitachi H9000NAR microscope equipped with a high angle electronic hollow cone unit.

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Li, Yan, Han Zhang, Zhaohui Huang, Emiliano Bilotti, and Ton Peijs. "Graphite Nanoplatelet Modified Epoxy Resin for Carbon Fibre Reinforced Plastics with Enhanced Properties." Journal of Nanomaterials 2017 (2017): 1–10. http://dx.doi.org/10.1155/2017/5194872.

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A simple approach to deliver graphene or graphite nanoplatelets (GNPs) into carbon fibre reinforced plastic (CFRPs) to enhance the multifunctional properties of carbon/epoxy laminates was demonstrated. GNPs improved the typically low interlaminar mechanical, thermal, and electrical properties of CFRPs after direct vacuum infusion of GNP doped resin obtained via in situ exfoliation by three-roll milling (TRM). Compared to high shear mixing or probe ultrasonication, TRM produces higher shear rates and stresses to exfoliate and finely disperse GNP particles within an epoxy matrix. This environmentally friendly and industrial scalable process does not require the use of solvents, additives, or chemical treatments. The flexural modulus and interlaminar shear strength (ILSS) of CFRPs was increased by 15% and by 18%, respectively, with the addition of 5 wt.% in situ exfoliated GNP in the doped epoxy resin. Out-of-plane electrical and thermal conductivity, at the same filler content, were, respectively, improved by nearly two orders of magnitude and 50%.

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R.A. Hamid, Asna, and Azlin F. Osman. "Effects of Ultrasonication Time on Thermal Stability and Swelling Behaviour of The Commercial Organo-Montmorillonite (O-MMT)." International Journal of Engineering & Technology 7, no. 2.23 (April 20, 2018): 288. http://dx.doi.org/10.14419/ijet.v7i2.23.11934.

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In this contribution, we report the effect of ultrasonication time on thermal stability and swelling of organically modified montmorillonite (O-MMT) upon ultrasonication in a water medium. In the production of well-exfoliated polymer/clay nanocomposite, ultrasonication was employed as a method to exfoliate and disperse organically modified montmorillonite (O-MMT) platelets prior to melt compounding with the polymer matrix. The suspension of distilled water and O-MMT was magnetically stirred for 2 hours and then ultrasonicated at the different sonicating time, namely, 2 minutes, 5 minutes, 10 minutes, 15 minutes and 20 minutes (min) at room temperature. Thermogravimetry analysis (TGA) suggested that dispersion of the O-MMT by ultrasonication for 5 minutes resulted in thermal stability enhancement without destruction of the organic surface modifier structure and bonding on the clay platelets. X-ray diffraction (XRD) also indicated that application of 5 minutes ultrasonication time has most obviously improved the swelling of the O-MMT platelets. This was further proved by Field emission scanning electron microscope (FeSEM) which revealed greater interlayer spacing within the O-MMT platelets was obtained.

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SUN, Pingchuan. "Rubber/exfoliated-clay nano-composite gel: Direct exfolia-tion of montmorillonite by telechelic liquid rubber." Chinese Science Bulletin 49, no. 15 (2004): 1664. http://dx.doi.org/10.1360/04wb0106.

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He, Kejun, Sharon M. Donovan, Ivan V. Ivanov, Jennifer S. Goldsby, Laurie A. Davidson, and Robert S. Chapkin. "Assessing the Multivariate Relationship between the Human Infant Intestinal Exfoliated Cell Transcriptome (Exfoliome) and Microbiome in Response to Diet." Microorganisms 8, no. 12 (December 18, 2020): 2032. http://dx.doi.org/10.3390/microorganisms8122032.

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Gut microbiota and the host exist in a mutualistic relationship, with the functional composition of the microbiota strongly influencing the health and well-being of the host. In addition to the standard differential expression analysis of host genes to assess the complex cross-talk between environment (diet), microbiome, and host intestinal physiology, data-driven integrative approaches are needed to identify potential biomarkers of both host genes and microbial communities that characterize these interactions. Our findings demonstrate that the complementary application of univariate differential gene expression analysis and multivariate approaches such as sparse Canonical Correlation Analysis (sCCA) and sparse Principal Components Analysis (sPCA) can be used to integrate data from both the healthy infant gut microbial community and host transcriptome (exfoliome) using stool derived exfoliated cells shed from the gut. These approaches reveal host genes and microbial functional categories related to the feeding phenotype of the infants. Our findings also confirm that combinatorial noninvasive -omic approaches provide an integrative genomics-based perspective of neonatal host-gut microbiome interactions.

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Toyoda, Ryojun, Ryota Sakamoto, Naoya Fukui, Ryota Matsuoka, Mizuho Tsuchiya, and Hiroshi Nishihara. "A single-stranded coordination copolymer affords heterostructure observation and photoluminescence intensification." Science Advances 5, no. 1 (January 2019): eaau0637. http://dx.doi.org/10.1126/sciadv.aau0637.

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Few artificial systems can be exfoliated into, and observed as, single wires with lengths of more than several micrometers, and no previous example features a copolymer structure; this is in contrast with biopolymers such as single-strand DNAs. Here, we create a set of one-dimensional coordination copolymers featuring bis(dipyrrinato)zinc complex motifs in the main chain. A series of random copolymers is synthesized from two types of bridging dipyrrin proligand and zinc acetate, with various molar ratios between the proligands. Sonication of the bulk solid copolymer in organic solvent exfoliates single strands with lengths of 1.4 to 3.0 μm. Atomic force microscopy at ambient conditions visualizes the copolymer structure as height distributions. The copolymer structure improves its photoluminescence (up to 32%) relative to that of the corresponding homopolymers (3 and 10%). Numerical simulation based on a restricted random walk model reproduces the photoluminescence intensification, suggesting at the same time the existence of fast intrawire exciton hopping.

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Catling, P. M., and K. W. Spicer. "The separation of Betulapopulifolia and Betulapendula and their status in Ontario." Canadian Journal of Forest Research 18, no. 8 (August 1, 1988): 1017–26. http://dx.doi.org/10.1139/x88-155.

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The North American Betulapopulifolia differs from the European Betulapendula in having a larger number of peltate resin glands on greyish twigs, leaves with long–caudate tips, and a dense pubescence on the adaxial surface of the pistillate scales. Furthermore, B. populifolia is a plant of acid, peaty, or sandy substrates, whereas B. pendula grows in acid to neutral or occasionally slightly alkaline substrates. The bark of B. pendula exfoliates in long thin strands, whereas in B. populifolia it exfoliates as small, very thin rectangular flakes or appears not to exfoliate at all. The basal parts of older trunks of B. pendula often develop vertical fissures, which never develop in B. populifolia. Analysis of variance suggests that the most useful quantitative characters for distinguishing the two species are scale width and the length/width ratio of the terminal one-quarter of the leaf. Several other quantitative characters are useful discriminators but are not entirely reliable by themselves. Discriminant analyses with and without qualitative characters separated a sample of North American B. populifolia from a sample of European B. pendula. The derived discriminant formula placed many members of a variable natural population from near Ottawa in an intermediate position, suggesting hybridization. The use of heavily weighted qualitative characters in the discriminant formula placed much of the hybrid population in the B. populifolia group, whereas the use of quantitative characters alone placed much of the hybrid population in the B. pendula group. As putative hybrids are being widely distributed by nurseries, the identification of the two species is likely to become increasingly problematic. Betulapendula is a widespread and naturally spreading escape from cultivation in southern Ontario, while B. populifolia is a native species confined in Ontario to the eastern portion of the province between the Ottawa and St. Lawrence rivers, with a possible outlier in Elgin County in southwestern Ontario.

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Lang, Fengqun, Hiroshi Yamaguchi, and Hiroshi Sato. "Package Reliability of the SiC Power Modules in Harsh Environments." Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT) 2011, HITEN (January 1, 2011): 000139–44. http://dx.doi.org/10.4071/hiten-paper2-flang.

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To evaluate the package reliability of the SiC power modules in harsh environments, the SiC Schottky Barrier Diodes (SBDs) were die bonded to the Si3N4/Cu/Ni(P) substrate with Au-Ge eutectic solder using a vacuum reflow furnace. The Si3N4/Cu/Ni(P) substrates are active metalized copper (AMC). The bonded samples were isothermally aged at 330°C and tested under thermal cycling conditions in the temperature range of −40–300°C in air. During the isothermal aging, cracks of the Ni(P) layer developed, resulting in oxidation of the Cu power path. Decrease in the die bond strength and increase in the electrical resistivity were observed due to the Cu power path oxidation and the growth of the Ni-Ge intermetalic compound (IMC) in the joint. Under the thermal cycling conditions, the metallization of the substrate suffers from serious surface roughness, which greatly degrades the die-attach reliability. The Al electrode was found to seriously exfoliate from the SiC-SBDs due to the thermal stress. After 521 cycles, almost all the Al electrode exfoliated form the anode. Benefit from the excellent mechanical properties of Si3N4, no detachment of the Cu layer was observed from the Si3N4 substrate after 1079 cycles, while the Cu layer detached from the AlN substrate only after 12 cycles.

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Gallardo-López, Ángela, Javier Castillo-Seoane, Carmen Muñoz-Ferreiro, Cristina López-Pernía, Ana Morales-Rodríguez, and Rosalía Poyato. "Flexure Strength and Fracture Propagation in Zirconia Ceramic Composites with Exfoliated Graphene Nanoplatelets." Ceramics 3, no. 1 (March 5, 2020): 78–91. http://dx.doi.org/10.3390/ceramics3010009.

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In this work, the flexure strength and fracture propagation mechanisms in yttria tetragonal zirconia (3YTZP) dense composites with 1 and 5 vol.% exfoliated graphene nanoplatelets (e-GNP) were assessed. The composite powders were processed by dry planetary ball milling to exfoliate the as-received GNP, and then densified by spark plasma sintering (SPS). The hardness and Young’s modulus were measured by Vickers indentation and the impulse-echo technique, respectively. Flexural strength and modulus were estimated by four-point bending tests. Finally, cracks originated by Vickers indentations were analyzed by scanning electron microscopy (SEM). The Raman spectra and SEM observations showed a reduction in the number of graphene layers and most remarkably in the lateral size of the e-GNP, achieving a very homogeneous distribution in the ceramic matrix. The hardness, elastic modulus, and flexural strength of the 3YTZP matrix did not vary significantly with the addition of 1 vol.% e-GNP, but they decreased when the content increased to 5 vol.%. The addition of e-GNP to 3YTZP increased its reliability under bending, and the small lateral size of the e-GNP produced isotropic fracture propagation. However, the energy dissipation mechanisms conventionally attributed to the larger GNP such as fracture deflection or blocking were limited.

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Qiao, Xu, Zhi Lin, Yuan Yuan Si, Xiao Dan Lin, Shao Wei Cui, and Xing Song Hu. "Preparation of High-Quality Graphene by Sodium Borohydride Reducing Stage-1 FeCl₃-GIC via In Situ Hydrogen Exfoliation." Key Engineering Materials 744 (July 2017): 458–62. http://dx.doi.org/10.4028/www.scientific.net/kem.744.458.

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High-quality graphene is prepared via In Situ hydrogen exfoliation of the reaction of stage-1 FeCl3-GIC with sodium borohydride solution, followed by washings and sonication. The hydrogen evolved from the borohydride exfoliates the GIC and reduces defect structure in the graphene simultaneously, make it more conjugated. Raman spectrum results show the intensity ratio of the D and G peak is about 0.09, even smaller than that of the original graphite, which is 0.17. The only C1s peak locating at 284.9 eV in another way supports the only one structure in the graphene. SEM image of exfoliated graphene Fig. 2(f) shows that the graphene obtained has curly morphology, which is significantly different from graphite flakes. TEM of the graphene shows a single layer graphene and its overlap with other graphene. Atomic force microscopy (AFM) measure shows that the average thickness of graphene sheets is about 0.530 nm. Proving that the high quality graphene prepared is chiefly single layer. After compression molded into graphene mat, its conductivity reaches 2.85×105S/m, which is about one third of the theoretical value of graphene. This method is promising for mass production of high-quality graphene.

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Mai, Tam Thanh, Nhan Thuc Chi Ha, Van Thi Thanh Khuat, and Huy Thuc Ha. "Investigation of chemical reduction of graphene oxide with many reduced agents." Science and Technology Development Journal 18, no. 2 (June 30, 2015): 197–210. http://dx.doi.org/10.32508/stdj.v18i2.1185.

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Graphene based on graphite oxide prepared by chemical reduction method is always interesting for scientists since the early days of discovery of graphene. Many different reducing agents are recommended, however every reducing agent is only active on one type of functional groups on the structure of graphene oxide. For studying clearly the reducing ability of the chemical reducing agent, this research has focused on investigating the possibility of 3 reducing agents such as N2H4, NaBH4 and HI. Besides, polyethylene oxide is also used as modified agent to completely exfoliate of graphite oxide before continuing the reduction process. Based on spectral analysis methods such as Fourier transform infrared (FTIR), UV-Vis and Raman spectroscopy, we have demonstrated the reduced ability of each agent, and strong reducing agent is HI. Exfoliated structure of MGO-PEG and graphene is demonstrated by means of X-ray diffraction analysis and scanning (SEM) and transmittance (TEM) electron microscopy. The thermal analysis methods such as TGA and DSC also contribute to clarify the role of each reducing agent. Finally, the four-probe method was used to determine the sheets resistance of the graphene film: RGO-HI (120 Ω/square), RGO-Na (1300 Ω/square) and RGO-Hz (1500 Ω/square). This study contributes to clarify the reducing ability of N2H4, NaBH4 and HI on the same kind of graphene oxide that has not yet been studied.

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KUMAGAI, Naonori, Chiyoko N. INOUE, Yoshiaki KONDO, and Kazuie IINUMA. "Mitogenic action of lysophosphatidic acid in proximal tubular epithelial cells obtained from voided human urine." Clinical Science 99, no. 6 (November 21, 2000): 561–67. http://dx.doi.org/10.1042/cs0990561.

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Focal tubular cell multiplication at sites on an injured nephron is a critical event in the recovery phase following acute tubular necrosis. During this process, numerous viable tubular cells exfoliate and are shed into the urine. Lysophosphatidic acid (LPA) is generated in the plasma membrane of injured cells and acts as an intercellular mediator of various biological processes, including inflammation, proliferation and repair. In the present study, exfoliated proximal tubule (PT) cells were isolated from human urine and the mitogenic effects of LPA were investigated as a model of repair and proliferation following renal injury. LPA stimulated a 23.5% increase in DNA synthesis, a 29.4% increase in cell number and an 86.6% decrease in cAMP content. All of these responses were pertussis toxin sensitive, indicating the involvement of Gi-type G-proteins in LPA signalling. Conversely, the LPA-induced DNA synthesis and the decrease in intracellular cAMP content were insensitive to wortmannin, an inhibitor of phosphatidylinositol 3-kinase (PI3K), suggesting a mitogenic response via PI3K-independent mechanisms. Furthermore, we detected specific mRNA transcripts for the recently cloned human LPA-receptors, endothelial differentiation gene (Edg)-2 and Edg-4 (Edg-2 ≫ Edg-4) by reverse transcription-PCR in PT cells. Our data suggest that LPA may behave as a local growth factor in PT cells following tubular injury.

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Zhang, Chi, Junyang Tan, Yikun Pan, Xingke Cai, Xiaolong Zou, Hui-Ming Cheng, and Bilu Liu. "Mass production of 2D materials by intermediate-assisted grinding exfoliation." National Science Review 7, no. 2 (October 21, 2019): 324–32. http://dx.doi.org/10.1093/nsr/nwz156.

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Abstract The scalable and high-efficiency production of 2D materials is a prerequisite to their commercial use. Currently, only graphene and graphene oxide can be produced on a ton scale, and the inability to produce other 2D materials on such a large scale hinders their technological applications. Here we report a grinding exfoliation method that uses micro-particles as force intermediates to resolve applied compressive forces into a multitude of small shear forces, inducing the highly efficient exfoliation of layer materials. The method, referred to as intermediate-assisted grinding exfoliation (iMAGE), can be used for the large-scale production of many 2D materials. As an example, we have exfoliated bulk h-BN into 2D h-BN with large flake sizes, high quality and structural integrity, with a high exfoliation yield of 67%, a high production rate of 0.3 g h−1 and a low energy consumption of 3.01 × 106 J g−1. The production rate and energy consumption are one to two orders of magnitude better than previous results. Besides h-BN, this iMAGE technology has been used to exfoliate various layer materials such as graphite, black phosphorus, transition metal dichalcogenides, and metal oxides, proving its universality. Molybdenite concentrate, a natural low-cost and abundant mineral, was used as a demo for the large-scale exfoliation production of 2D MoS2 flakes. Our work indicates the huge potential of the iMAGE method to produce large amounts of various 2D materials, which paves the way for their commercial application.

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Xiao, Peng, Ju-Hyung Kim, and Soonmin Seo. "Flexible and Stretchable Liquid Metal Electrodes Working at Sub-Zero Temperature and Their Applications." Materials 14, no. 15 (August 2, 2021): 4313. http://dx.doi.org/10.3390/ma14154313.

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We investigated characteristics of highly flexible and stretchable electrodes consisting of Galinstan (i.e., a gallium-based liquid metal alloy) under various conditions including sub-zero temperature (i.e., <0 °C) and demonstrated solar-blind photodetection via the spontaneous oxidation of Galinstan. For this work, a simple and rapid method was introduced to fabricate the Galinstan electrodes with precise patterns and to exfoliate their surface oxide layers. Thin conductive films possessing flexibility and stretchability can be easily prepared on flexible substrates with large areas through compression of a dried suspension of Galinstan microdroplets. Furthermore, a laser marking machine was employed to facilitate patterning of the Galinstan films at a high resolution of 20 μm. The patterned Galinstan films were used as flexible and stretchable electrodes. The electrical conductivity of these electrodes was measured to be ~1.3 × 106 S m−1, which were still electrically conductive even if the stretching ratio increased up to 130% below 0 °C. In addition, the surface oxide (i.e., Ga2O3) layers possessing photo-responsive properties were spontaneously formed on the Galinstan surfaces under ambient conditions, which could be solely exfoliated using elastomeric stamps. By combining Galinstan and its surface oxide layers, solar-blind photodetectors were successfully fabricated on flexible substrates, exhibiting a distinct increase of up to 14.7% in output current under deep ultraviolet irradiation (254 nm wavelength) with an extremely low light intensity of 0.1 mW cm−2, whereas no significant change was observed under visible light irradiation.

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JIA, FEIFEI, and SHAOXIAN SONG. "EXFOLIATION AND CHARACTERIZATION OF LAYERED SILICATE MINERALS: A REVIEW." Surface Review and Letters 21, no. 02 (April 2014): 1430001. http://dx.doi.org/10.1142/s0218625x14300019.

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Exfoliated silicate minerals have attracted great attentions because of the dramatic improvement in properties. This paper highlights the preparation of exfoliated silicate minerals, including physical, chemical, mixed physical and chemical methods. The mechanisms by which silicates are exfoliated and the important influential factors are also summarized. Finally, the instrumental techniques to characterize the exfoliated structure and exfoliation degree are presented.

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Zhao, Ji Jin, Xiao Xia Li, Yu Xiang Guo, Tong Sun, and Sen Ma. "Preparation and Microstructure of Two Kinds of Exfoliated Graphite." Advanced Materials Research 706-708 (June 2013): 211–14. http://dx.doi.org/10.4028/www.scientific.net/amr.706-708.211.

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Two kinds of exfoliated graphite have been prepared from graphite flake and graphite powder, and their preparation conditions were respectively optimized by orthogonal experiments and parallel experiments. The effect of graphite size on the characteristics of exfoliated graphite was researched. The microstructure of two kinds of exfoliated graphite was measured by SEM. The results show that the optimal preparation conditions for exfoliated graphite flake are as following: the mass-volume ratio of graphite to mixed acid is 1: 4, the volume ratio of nitric acid to phosphoric acid is 1: 2, the mass ratio of graphite to potassium permanganate is 1: 0.1, and the reaction temperature is 25°C. For exfoliated graphite powder, the optimal mass ratio of graphite powder to potassium permanganate is 1: 0.22, and the consumption of oxidant for exfoliated graphite powder is more than that for exfoliated graphite flake. The longitudinal expansion of graphite flake is more apparent than that of graphite powder and leads to a worm-like fluffy rope.

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Jermy, Andrew. "UPEC helps host to exfoliate." Nature Reviews Microbiology 10, no. 3 (February 13, 2012): 159. http://dx.doi.org/10.1038/nrmicro2758.

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Cassano, N., M. Carbonara, M. Grandolfo, S. Calabretta, C. Castellana, C. Coviello, S. Curia, et al. "A Multicenter Open Study on the Tolerability and Efficacy of a Cosmetic Treatment in Mild Acne Vulgaris during the Summer Months." European Journal of Inflammation 1, no. 2 (May 2003): 85–90. http://dx.doi.org/10.1177/1721727x0300100206.

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The improvement of acne vulgaris (AV) during summer months is a general opinion which is not universally accepted as some patients experience no change or even an aggravation of their AV during hot months. Therapeutic management of AV in summer is often difficult; in fact, most traditional anti-acne treatments are contraindicated or poorly tolerated during summer months. In this study we evaluated the tolerability and effectiveness of a cosmetic anti-acne treatment performed for 12 summer weeks in 347 patients (mean age, 19.4 yrs) with mild AV of the face. The study product (Exfoliac®) contained a mixture of alpha hydroxy acids and substances with moisturizing and/or lenitive effects. In the first 4 weeks, Exfoliac® 10 cream was applied twice a day (b.i.d.). The treatment in the following 8 weeks was decided on the basis of dermatologist's assessment of the clinical response and could consist in Exfoliac® 10 cream or Exfoliac® 15 cream, once daily (o.d.) or b.i.d. During the study period, patients used Exfoliac® cleansing gel. The cumulative results indicate a significant improvement of AV lesions and seborrhoea, irrespectively of sun exposure, and a good tolerability, even in sunbathed patients. Adverse reactions, mostly of mild severity, appeared to be independent of sunbathing or use of sunscreens and were observed in a small proportion of cases (6.8% in the first 4 weeks and 5.6% in the last 8 weeks). Our results suggest that this type of treatment is an effective and safe approach to patients with mild AV who require treatment in the summertime.

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Bannov, Alexander, Anastasya Timofeeva, Stepan Yusin, Ksenya Dyukova, E. A. Maximovskiy, Arina Ukhina, and Alexander Shibaev. "Synthesis of the Exfoliated Graphite from Graphite Oxide." Advanced Materials Research 1085 (February 2015): 171–75. http://dx.doi.org/10.4028/www.scientific.net/amr.1085.171.

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This article is devoted to investigation of the synthesis process of exfoliated graphite. Exfoliated graphite was obtained from graphite oxide using thermal exfoliation. Graphite oxide samples were synthesized using modified Hummers method. The influence of the synthesis process parameters such as heating rate, temperature, exposure time on the properties of graphite oxide were investigated. The as-received exfoliated graphite were tested as electrode for supercapacitors. The capacitance of the supercapacitors based on exfoliated graphite varied in a range of 17-129 F/g.

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Terence, Mauro Cesar, Ederson Esteves Silva, and Juan Alfredo Guevara Carrió. "Electrochemically Exfoliated Graphene." Journal of Nano Research 29 (December 2014): 29–33. http://dx.doi.org/10.4028/www.scientific.net/jnanor.29.29.

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We analyze graphene obtained by electrochemical exfoliation. This showed an interesting process for obtaining fast and low cost exfoliated graphene. Within a few minutes a large amount exfoliated graphite oxide was produced. Analysis by Raman spectroscopy of the exfoliated graphene showed the effectiveness of the process and the factors that may intensify the disorder of graphene obtained.

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Qi, Zheng-Hang, Yi Hu, Zhong Jin, and Jing Ma. "Tuning the liquid-phase exfoliation of arsenic nanosheets by interaction with various solvents." Physical Chemistry Chemical Physics 21, no. 23 (2019): 12087–90. http://dx.doi.org/10.1039/c9cp01052a.

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Fujita, Takeshi, Yoshikazu Ito, Yongwen Tan, Hisato Yamaguchi, Daisuke Hojo, Akihiko Hirata, Damien Voiry, Manish Chhowalla, and Mingwei Chen. "Chemically exfoliated ReS2nanosheets." Nanoscale 6, no. 21 (2014): 12458–62. http://dx.doi.org/10.1039/c4nr03740e.

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Chattopadhyay, Jayanta, Arnab Mukherjee, Soma Chakraborty, JungHo Kang, Peter J. Loos, Kevin F. Kelly, Howard K. Schmidt, and W. E. Billups. "Exfoliated soluble graphite." Carbon 47, no. 13 (November 2009): 2945–49. http://dx.doi.org/10.1016/j.carbon.2009.06.053.

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37

Nayak, Susanginee, Lagnamayee Mohapatra, and Kulamani Parida. "Visible light-driven novel g-C3N4/NiFe-LDH composite photocatalyst with enhanced photocatalytic activity towards water oxidation and reduction reaction." Journal of Materials Chemistry A 3, no. 36 (2015): 18622–35. http://dx.doi.org/10.1039/c5ta05002b.

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Jeffery, A. Anto, C. Nethravathi, and Michael Rajamathi. "Scalable large nanosheets of transition metal disulphides through exfoliation of amine intercalated MS2 [M = Mo, W] in organic solvents." RSC Advances 5, no. 63 (2015): 51176–82. http://dx.doi.org/10.1039/c5ra08402d.

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Cheng, Jing-Zhao, Zhi-Rong Tan, Yu-Qin Xing, Zhao-Qi Shen, Yu-Jie Zhang, Li-Lin Liu, Kai Yang, Long Chen, and Shi-Yong Liu. "Exfoliated conjugated porous polymer nanosheets for highly efficient photocatalytic hydrogen evolution." Journal of Materials Chemistry A 9, no. 9 (2021): 5787–95. http://dx.doi.org/10.1039/d0ta11479k.

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Tao, You, Wenyan Ji, Xuesong Ding, and Bao-Hang Han. "Exfoliated covalent organic framework nanosheets." Journal of Materials Chemistry A 9, no. 12 (2021): 7336–65. http://dx.doi.org/10.1039/d0ta12122c.

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Dong, Qingqing, Xiaodong Zhuang, Zhi Li, Bin Li, Bin Fang, Cunzhong Yang, Haifen Xie, Fan Zhang, and Xinliang Feng. "Efficient approach to iron/nitrogen co-doped graphene materials as efficient electrochemical catalysts for the oxygen reduction reaction." Journal of Materials Chemistry A 3, no. 15 (2015): 7767–72. http://dx.doi.org/10.1039/c5ta00556f.

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Cheng, Zhi-lin, Zhan-sheng Ma, Hong-liang Ding, and Zan Liu. "Environmentally friendly, scalable exfoliation for few-layered hexagonal boron nitride nanosheets (BNNSs) by multi-time thermal expansion based on released gases." Journal of Materials Chemistry C 7, no. 46 (2019): 14701–8. http://dx.doi.org/10.1039/c9tc03985f.

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Chng, Elaine Lay Khim, Zdeněk Sofer, and Martin Pumera. "MoS2 exhibits stronger toxicity with increased exfoliation." Nanoscale 6, no. 23 (2014): 14412–18. http://dx.doi.org/10.1039/c4nr04907a.

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Singh, R. K., S. Maulik, S. Mitra, R. K. Mondal, P. S. Basu, S. Roychowdhury, and C. K. Panda. "Human papillomavirus prevalence in postradiotherapy uterine cervical carcinoma patients: correlation with recurrence of the disease." International Journal of Gynecologic Cancer 16, no. 3 (2006): 1048–54. http://dx.doi.org/10.1136/ijgc-00009577-200605000-00016.

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To understand the role of human papillomavirus (HPV) in recurrence of uterine cervical cancer (CA-CX) after radiotherapy, we have analyzed the HPV prevalence in the exfoliated cells of 56 patients and their corresponding plasma. HPV DNA was detected in exfoliated cells of 78% (44/56) patients (HPV-16, 68%; HPV-18, 14%; HPV-X [other than 16, 18], 11%; and mixed infection of HPV-16 and HPV-18 in three cases). HPV DNA in plasma was present in only 25% (11/44) of the HPV-positive exfoliated cells (positive predictive value, 100%; negative predictive value, 27%) with concordance in HPV types. The recurrence of the disease was significantly associated with the presence of HPV in the exfoliated cell (P = 0.01) and plasma (P = 0.007) as well as high viral load in the exfoliated cell (P = 0.0002). Kaplan–Meier disease-free estimates have also shown the significant association between HPV prevalence in plasma and recurrence of the disease (P = 0.045). Thus, it indicates that in postradiotherapy CA-CX patients, the high viral load in the exfoliated cell as well as HPV presence in the plasma samples could be used in early detection of the patients at increased risk for disease recurrence and progression.

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Jeffery, A. Anto, A. Pradeep, and Michael Rajamathi. "Preparation of titanate nanosheets and nanoribbons by exfoliation of amine intercalated titanates." Physical Chemistry Chemical Physics 18, no. 18 (2016): 12604–9. http://dx.doi.org/10.1039/c6cp01624c.

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Tan, Xingxing, Wancheng Zhao, and Tiancheng Mu. "Controllable exfoliation of natural silk fibers into nanofibrils by protein denaturant deep eutectic solvent: nanofibrous strategy for multifunctional membranes." Green Chemistry 20, no. 15 (2018): 3625–33. http://dx.doi.org/10.1039/c8gc01609g.

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Gao, Lin, and Ye Wei. "Sustained Release Properties of Aminophylline Sustained Release Tablets Based on Exfoliated Graphite." Advanced Materials Research 1023 (August 2014): 67–70. http://dx.doi.org/10.4028/www.scientific.net/amr.1023.67.

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This study attempted to develop sustained release tablets based on exfoliated graphite. The in vitro evaluation of the prepared tablets was carried out to study its sustained release properties by means of UV/VIS spectroscopy. The results show that the release rate of aminophylline decreases with the increase of the content of graphite for the aminophylline sustained release tablets based on exfoliated graphite. The graphite in the aminophylline sustained release tablets will delay the release of aminophylline when the exfoliated graphite content in the sustained release tablets is less than 25%, the graphite will prevent the release of a part of the aminophylline when the exfoliated graphite content exceeds 40%. The reproducibility of the prepared aminophylline sustained release tablets is acceptable.

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Sharma, Mukesh, Dibyendu Mondal, Nripat Singh, and Kamalesh Prasad. "Biomass derived solvents for the scalable production of single layered graphene from graphite." Chemical Communications 52, no. 58 (2016): 9074–77. http://dx.doi.org/10.1039/c6cc00256k.

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Novikau, Uladzimir, Ihar Razanau, and Sviatlana Filipovich. "Novel Method of Graphite Exfoliation." MRS Advances 1, no. 19 (2016): 1395–400. http://dx.doi.org/10.1557/adv.2016.190.

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ABSTRACTThe paper describes a novel method of exfoliated graphite synthesis. The method includes synthesis of graphite intercalation compound in liquid ammonia medium and subsequent intercalate decomposition with graphite exfoliation. Influence of the experimental parameters on the morphology and structure of the exfoliated graphite is shown. Comparison of the developed exfoliation method to the high-temperature oxidation-reduction method used in industrial scale nowadays is presented. A number of application areas for the synthesized exfoliated graphite are described.

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Todorova, Nadia, Ilias Papailias, Tatiana Giannakopoulou, Nikolaos Ioannidis, Nikos Boukos, Panagiotis Dallas, Miroslava Edelmannová, Martin Reli, Kamila Kočí, and Christos Trapalis. "Photocatalytic H2 Evolution, CO2 Reduction, and NOx Oxidation by Highly Exfoliated g-C3N4." Catalysts 10, no. 10 (October 3, 2020): 1147. http://dx.doi.org/10.3390/catal10101147.

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g-C3N4, with specific surface area up to 513 m2/g, was prepared via three successive thermal treatments at 550 °C in air with gradual precursor mass decrease. The obtained bulk and exfoliated (1ex, 2ex and 3ex) g-C3N4 were characterized and tested as photocatalysts for H2 production, CO2 reduction and NOx oxidation. The exfoliated samples demonstrated graphene-like morphology with detached (2ex) and sponge-like framework (3ex) of layers. The surface area increased drastically from 20 m2/g (bulk) to 513 m2/g (3ex). The band gap (Eg) increased gradually from 2.70 to 3.04 eV. Superoxide radicals (·O2−) were mainly formed under UV and visible light. In comparison to the bulk, the exfoliated g-C3N4 demonstrated significant increase in H2 evolution (~6 times), CO2 reduction (~3 times) and NOx oxidation (~4 times) under UV light. Despite the Eg widening, the photocatalytic performance of the exfoliated g-C3N4 under visible light was improved too. The results were related to the large surface area and low e−-h+ recombination. The highly exfoliated g-C3N4 demonstrated selectivity towards H2 evolution reactions.

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Journal articles on the topic 'Exfoliace'

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