Journal articles: 'Natural source materials'

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Kumar, Arun. "Natural Materials—Interesting Candidates for Carbon Nanomaterials." Physchem 1, no. 1 (January 19, 2021): 4–25. http://dx.doi.org/10.3390/physchem1010002.

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This review sums up the techniques used for the synthesis of carbon nanotubes (CNTs), carbon nanofibers (CNFs), and carbon nanospheres (CNSs) by employing catalysts of natural origin. Establishing large-scale production and commercial applications of CNTs for a sustainable society is still of high apprehension. In this regard, one of the major factors is the starting materials such as precursors and catalyst sources. However, natural materials contain a minor quantity of metals or metal oxides and could be employed as a catalyst source for the synthesis of CNTs, providing the possibility to replace expensive catalyst sources. A large number of successful studies have been completed so far and confirm that these developed methods for carbon nanomaterials synthesis exhibiting high quality from common natural materials are not only possible but, most importantly, promising and scalable. This review also highlights purification methods and recent promising applications of as-synthesized CNTs.

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Lu, Xu, and Donald T. Morelli. "Natural mineral tetrahedrite as a direct source of thermoelectric materials." Physical Chemistry Chemical Physics 15, no. 16 (2013): 5762. http://dx.doi.org/10.1039/c3cp50920f.

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Molina-Santiago, Carlos, Antonio de Vicente, and Diego Romero. "Bacterial extracellular matrix as a natural source of biotechnologically multivalent materials." Computational and Structural Biotechnology Journal 19 (2021): 2796–805. http://dx.doi.org/10.1016/j.csbj.2021.05.008.

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Sahiner, Nurettin, and Selin Sagbas. "Polymeric ionic liquid materials derived from natural source for adsorption purpose." Separation and Purification Technology 196 (May 2018): 208–16. http://dx.doi.org/10.1016/j.seppur.2017.05.048.

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Paris, Oskar, Ingo Burgert, and Peter Fratzl. "Biomimetics and Biotemplating of Natural Materials." MRS Bulletin 35, no. 3 (March 2010): 219–25. http://dx.doi.org/10.1557/mrs2010.655.

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AbstractNatural materials display a wealth of structures and fulfill a variety of functions. Hierarchical structuring is one of the keys to providing multifunctionality and to adapting to varying needs of an organism. As a consequence, the natural environment represents not only a direct and renewable source of useful materials, such as wood, plant fibers, or even proteins of pharmaceutical importance, but also an enormous “database” of structures with exceptional mechanical, optical, or magnetic properties. Rather than focusing on the direct use of natural materials, this article discusses the use of structures that appeared in evolution and have been implemented in artificial materials of an entirely different type and chemical composition. This may be done either by directly copying the structure (biotemplating) or by extracting the design principles encoded in them for the fabrication of novel bioinspired materials.

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Domanskaya, Irina K., Fedor Kapustin, and Rudolf Hela. "Concrete Recycling as a Source of Polyfractional Mineral Raw Materials." Solid State Phenomena 309 (August 2020): 126–31. http://dx.doi.org/10.4028/www.scientific.net/ssp.309.126.

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The problems of concrete recycling as a complex poly-reinforced composite characterized by unstable composition and properties are discussed. The peculiarity of recycling concrete scrap is that its return to the production cycle can be carried out in the form of different products: coarse aggregate (recycled aggregate), fine aggregate (sand from crushed concrete), as well as in the form of a dust-like fraction. It is shown that aggregates made of crushed concrete are inferior to natural analogues due to the presence of cement-sand mortar in their composition. Given the growing threat of depletion of natural resources, it seems appropriate to consider construction waste not only as secondary resources for the production of concrete and mortars, but also more widely: as a promising technogenic source of polymineral raw materials, including for firing technologies.

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Fakhruddin, Ahmad Kamil, and Hasmaliza M. Mohamad. "Mechanical Properties of Bioactive Glass Fabricated Using Natural Resources Materials." Materials Science Forum 1010 (September 2020): 620–25. http://dx.doi.org/10.4028/www.scientific.net/msf.1010.620.

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Bioactive glass use silica (SiO2), calcium carbonate (CaCO3), sodium carbonate (Na2CO3), phosphorus pentoxide (P2O5) as raw materials. In this work, bioactive glass (BG); 45S5 bioactive glass was synthesized using natural resources materials; rice husk ash (RHA) as silica (SiO2) source and seashell (SS) as calcium carbonate (CaCO3) source through melt derived method. All raw materials were melted at 1400 °C and water quenched. The glass frit obtained was milled and sieved then analyzed using X-ray diffraction (XRD), Fourier Transform Infrared spectroscope (FTIR) and Scanning Electron Microscope (SEM). The mechanical properties 45S5 BG pellet was observed through diametral tensile stress (DTS). The XRD and FTIR pattern for all sample synthesized using natural resources raw materials show similar pattern with control sample 45S5 synthesis using pure raw materials. The mechanical properties for all samples also have not significantly different with control samples

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Papanicolaou, Elias, and Sridhar Gopalakrishna. "Natural Convection in Shallow, Horizontal Air Layers Encountered in Electronic Cooling." Journal of Electronic Packaging 117, no. 4 (December 1, 1995): 307–16. http://dx.doi.org/10.1115/1.2792110.

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A numerical study of natural convection induced in a horizontal, enclosed air layer due to a discrete, constant heat flux source at the bottom surface is carried out in this paper. The nature of the transition from conduction to a cellular convection regime for this discrete-heating case is characterized. Multiple sources are also considered and the results are compared to those for a single source. The governing equations of continuity, momentum, and energy conservation are formulated for a two-dimensional layer. The important parameters are the overall aspect ratio (length/height of the layer), the ratio of source length to total length, and the Rayleigh number. The effect of varying these parameters is investigated, and heat transfer correlations are derived, for both single and multiple sources, in the form Nus ∝ C (Ra)c>, where Nus is the Nusselt number averaged over each source. The value of C is found to depend strongly on the aspect ratio and the source size. Based on the heat transfer results, the tendency of each geometric configuration to fully attain transition to the convection regime is evaluated. This can provide guidelines for maintaining certain critical dimensions that best exploit natural convection effects, in systems where fan-driven cooling is not available.

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Klemm, Dieter, Emily D. Cranston, Dagmar Fischer, Miguel Gama, Stephanie A. Kedzior, Dana Kralisch, Friederike Kramer, et al. "Nanocellulose as a natural source for groundbreaking applications in materials science: Today’s state." Materials Today 21, no. 7 (September 2018): 720–48. http://dx.doi.org/10.1016/j.mattod.2018.02.001.

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Riekstina, Daina, Tamara Krasta, and Ruta Švinka. "Natural Radioactivity in Clay Ceramics and their Raw Materials in Latvia." Key Engineering Materials 788 (November 2018): 51–55. http://dx.doi.org/10.4028/www.scientific.net/kem.788.51.

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Natural radionuclides K-40, and Th-232, U-238 (Ra-226) decay chain products contained in building materials are the main source of radiation dose received by population and the only source of indoor radiation exposure. Present work contains results of the study of natural radionuclide activity level in clay, clay ceramics and silica bricks used in Latvia. Obtained data show that radionuclide content in different clay products can differ up to five times. However, determined activity index values for all tested materials, except fireproof bricks, were below radionuclide concentration level permitted by EU and Latvian national regulations. Comparison with analogous data from other North European and Baltic countries shows that average concentrations of natural radionuclides and activity index values for clay and clay bricks used in Latvia are on the same level as in other countries, except Sweden.

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Davies-Bolorunduro, Olabisi Flora, Abraham Ajayi, Isaac Adeyemi Adeleye, Alfinda Novi Kristanti, and Nanik Siti Aminah. "Bioprospecting for antituberculosis natural products – A review." Open Chemistry 19, no. 1 (January 1, 2021): 1074–88. http://dx.doi.org/10.1515/chem-2021-0095.

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Abstract There has been an increase in the reported cases of tuberculosis, a disease caused by Mycobacterium tuberculosis, which is still currently affecting most of the world’s population, especially in resource-limited countries. The search for novel antitubercular chemotherapeutics from underexplored natural sources is therefore of paramount importance. The renewed interest in studies related to natural products, driven partly by the growing incidence of MDR-TB, has increased the prospects of discovering new antitubercular drug leads. This is because most of the currently available chemotherapeutics such as rifampicin and capreomycin used in the treatment of TB were derived from natural products, which are proven to be an abundant source of novel drugs used to treat many diseases. To meet the global need for novel antibiotics from natural sources, various strategies for high-throughput screening have been designed and implemented. This review highlights the current antitubercular drug discovery strategies from natural sources.

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Traer, James, and Josh H. McDermott. "Statistics of natural reverberation enable perceptual separation of sound and space." Proceedings of the National Academy of Sciences 113, no. 48 (November 10, 2016): E7856—E7865. http://dx.doi.org/10.1073/pnas.1612524113.

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In everyday listening, sound reaches our ears directly from a source as well as indirectly via reflections known as reverberation. Reverberation profoundly distorts the sound from a source, yet humans can both identify sound sources and distinguish environments from the resulting sound, via mechanisms that remain unclear. The core computational challenge is that the acoustic signatures of the source and environment are combined in a single signal received by the ear. Here we ask whether our recognition of sound sources and spaces reflects an ability to separate their effects and whether any such separation is enabled by statistical regularities of real-world reverberation. To first determine whether such statistical regularities exist, we measured impulse responses (IRs) of 271 spaces sampled from the distribution encountered by humans during daily life. The sampled spaces were diverse, but their IRs were tightly constrained, exhibiting exponential decay at frequency-dependent rates: Mid frequencies reverberated longest whereas higher and lower frequencies decayed more rapidly, presumably due to absorptive properties of materials and air. To test whether humans leverage these regularities, we manipulated IR decay characteristics in simulated reverberant audio. Listeners could discriminate sound sources and environments from these signals, but their abilities degraded when reverberation characteristics deviated from those of real-world environments. Subjectively, atypical IRs were mistaken for sound sources. The results suggest the brain separates sound into contributions from the source and the environment, constrained by a prior on natural reverberation. This separation process may contribute to robust recognition while providing information about spaces around us.

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Polsongkram, Dheerachai, Pattanasuk Chamninok, Ki Seok An, and Supakorn Pukird. "Gases Effects for Synthesis ZnO Nanostructures Using Carbon Assisted." Applied Mechanics and Materials 607 (July 2014): 21–24. http://dx.doi.org/10.4028/www.scientific.net/amm.607.21.

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The morphologies of ZnO nanostructured were synthesized by carbon assisted. The materials source will be prepared by mixing Zn, ZnO and coconut shell charcoal or graphite. The materials source and silicon substrates were put in quartz tube of furnace, heated in difference gases. When, the temperature was cooled down to natural room temperature. The materials sources and silicon substrates will be studied by scanning electron microscope (SEM) and an energy dispersive X-rays instrument (EDX). The results showed that ZnO nanostructures materials such as nanotatrapods, nanowires, nanorods and nanoparticles can be observed.

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Lobo, Flávia C. M., Albina R. Franco, Emanuel M. Fernandes, and Rui L. Reis. "An Overview of the Antimicrobial Properties of Lignocellulosic Materials." Molecules 26, no. 6 (March 20, 2021): 1749. http://dx.doi.org/10.3390/molecules26061749.

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Pathogenic microbes are a major source of health and environmental problems, mostly due to their easy proliferation on most surfaces. Currently, new classes of antimicrobial agents are under development to prevent microbial adhesion and biofilm formation. However, they are mostly from synthetic origin and present several disadvantages. The use of natural biopolymers such as cellulose, hemicellulose, and lignin, derived from lignocellulosic materials as antimicrobial agents has a promising potential. Lignocellulosic materials are one of the most abundant natural materials from renewable sources, and they present attractive characteristics, such as low density and biodegradability, are low-cost, high availability, and environmentally friendly. This review aims to provide new insights into the current usage and potential of lignocellulosic materials (biopolymer and fibers) as antimicrobial materials, highlighting their future application as a novel drug-free antimicrobial polymer.

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Taskaev, Sergey, Vladimir Khovaylo, Maxim Ulyanov, Dmitriy Bataev, Ekaterina Danilova, and Danil Plakhotskiy. "Low Temperature Magnetocaloric Materials for Cryogenic Gas Liquefaction by Magnetic Cooling Technique." Key Engineering Materials 833 (March 2020): 176–80. http://dx.doi.org/10.4028/www.scientific.net/kem.833.176.

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Natural gas is rapidly gaining in geopolitical importance. Gas has grown from a marginal fuel in regionally disconnected markets to an energy source that is transported across great distances for consumption in many different economic sectors. Natural gas is the fuel of choice for consumers seeking for relatively low environmental impacts. As a result, the world’s gas consumption is projected to more than double over the next three decades, rising from 23 – 28 % of the total primary energy demand by 2030 and surpassing coal as the world's number two energy source and potentially overtaking oil's share in many large industrialized economies. This paper is devoted to a short review of materials used in the novel approach to natural gas liquefaction – magnetic cooling process.

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Astel, Aleksander, Grażyna Głosińska, Tadeusz Sobczyński, Leonard Boszke, Vasil Simeonov, and Jerzy Siepak. "Chemometrics in the assessment of the sustainable development rule implementation." Open Chemistry 4, no. 3 (September 1, 2006): 543–64. http://dx.doi.org/10.2478/s11532-006-0021-5.

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AbstractThe sustainable development rule implementation is tested by the application of chemometrics in the field of environmental pollution. A data set consisting of Cd, Pb, Cr, Zn, Cu, Mn, Ni, and Fe content in bottom sediment samples collected in the Odra River (Germany/Poland) is treated using cluster analysis (CA), principal component analysis (PCA), and source apportionment techniques. Cluster analysis clearly shows that pollution on the German bank is higher than on the Polish bank. Two latent factors extracted by PCA explain over 88 % of the total variance of the system, allowing identification of the dominant “semi-natural” and “anthropogenic” pollution sources in the river ecosystem. The complexity of the system is proved by MLR analysis of the absolute principal component scores (APCS). The apportioning clearly shows that Cd, Pb, Cr, Zn and Cu participate in an “anthropogenic” source profile, whereas Fe and Mn are “semi-natural”. Multiple regression analysis indicates that for particular elements not described by the model, the amounts vary from 4.2 % (Mn) to 13.1 % (Cr). The element Ni participates to some extent to each source and, in this way, is neither pure “semi-natural” nor pure “anthropogenic”. Apportioning indicates that the whole heavy metal pollution in the investigated river reach is 12510.45 mg·kg−1. The contribution of pollutants originating from “anthropogenic sources” is 9.04 % and from “semi-natural” sources is 86.53 %.

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Valdez, Benjamin, Michael Schorr, and Jose M. Bastidas. "The natural gas industry: equipment, materials, and corrosion." Corrosion Reviews 33, no. 3-4 (July 1, 2015): 175–85. http://dx.doi.org/10.1515/corrrev-2015-0012.

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AbstractCorrosion is a crucial worldwide problem that strongly affects the oil and gas industry. Natural gas (NG) is a source of energy used in industrial, residential, commercial, and electric applications. The abundance of NG in many countries augurs a profitable situation for the vast energy industry. NG is considered friendlier to the environment and has lesser greenhouse gas emissions compared with other fossil fuels. In the last years, shale gas is increasingly exploited in the USA and in Europe, using a hydraulic fracturing (fracking) technique for releasing gas from the bedrock by injection of saline water, acidic chemicals, and sand to the wells. Various critical sectors of the NG industry infrastructure suffer from several types of corrosion: steel casings of production wells and their drilling equipment, gas-conveying pipelines including pumps and valves, plants for regasification of liquefied NG, and municipal networks of NG distribution to the consumers. Practical technologies that minimize or prevent corrosion include selection of corrosion-resistant engineering materials, cathodic protection, use of corrosion inhibitors, and application of external and internal paints, coatings, and linings. Typical cases of corrosion management in the NG industry are presented based on the authors’ experience and knowledge.

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Pitri, Rina Muhayah Noor. "PEMANFAATAN TUMBUHAN HUTAN SEBAGAI BAHAN BAKU UNIT USAHA JAMU DAN PENGOLAHAN BAHAN ALAM DI KALIMANTAN SELATAN." EnviroScienteae 12, no. 3 (December 10, 2016): 338. http://dx.doi.org/10.20527/es.v12i3.2458.

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The existence of forest plants have been the source of traditional medicine for local communities. The use of natural materials by local communitiies as part of the medicinal treatment is done for subsistence. Not many identifiable utilization of the forest plants to meet the needs of business units herbal raw materials and processing of natural materials. This study seeks to identify the utilization of forest plants as raw material for herbal medicine business unit and the processing of natural materials in South Kalimantan. Mapping the distribution of the manufacturing herbal and natural ingredients also conducted and analyzed its association with the presence of the plant and within the forest. Data is collected using semi-structured interview to further analyzed descriptively. The collection of layers that constitute thematic information for the analysis of Geographic Information Systems. GIS analysis using ArcView 3.3 software. The results showed that the mixture dipterocarp forest is a forest type that is the source material for herbal medicine business unit and the processing of natural materials in South Kalimantan. The business unit is the most widely used natural materials from the forest is the micro and small (≤ 50%) or medium sized business units are relatively few industries using natural materials from the forest (± 10%). The distribution of herbal medicine business unit and the processing of natural materials in South Kalimantan uneven. Herbal medicine business unit and the processing of natural materials is also limited to the city of Banjarmasin, Martapura, Banjarbaru, Amuntai, Barabai. Distance to the forest as a source of raw materials and distribution of herbal industry/processing of natural materials not correlate significantly. The rapid development of urban economy and cultural factors related to the presence of viscous processing units herbal and natural ingredients.

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Boreham, C. J., J. M. Hope, and B. Hartung-Kagi. "UNDERSTANDING SOURCE, DISTRIBUTION AND PRESERVATION OF AUSTRALIAN NATURAL GAS: A GEOCHEMICAL PERSPECTIVE." APPEA Journal 41, no. 1 (2001): 523. http://dx.doi.org/10.1071/aj00026.

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Natural gases from all of Australia’s major gas provinces in the Adavale, Amadeus, Bass, Bonaparte, Bowen/ Surat, Browse, Canning, Carnarvon, Cooper/Eromanga, Duntroon, Gippsland, Otway and Perth basins have been examined using molecular and carbon isotopic compositions in order to define their source, maturity and secondary alteration processes.The molecular compositions of the gaseous hydrocarbons range from highly wet to extremely dry. On average, reservoired gases predominantly derived from land plants are slightly wetter than those derived from marine sources. The non-hydrocarbon gases CO2 and N2 were sourced from both inorganic and organic materials. A mantle and/or igneous origin is likely in the majority of gases with CO2 contents >5%. For gases with lower CO2 contents, an additional organic input, associated with hydrocarbon generation, is recognised where δ13C CO2 is A strong inter-dependency between source and maturity has been recognised from the carbon isotopic composition of individual gaseous hydrocarbons. This relationship has highlighted some shortcomings of common graphical tools for interpretation of carbon isotopic data. The combination of the carbon isotopic composition of gaseous hydrocarbons and the low molecular weight nalkanes in the accompanying oil allows our knowledge of oil-source correlations and oil families to be used to correlate gases with their sources. This approach has identified source rocks for gas ranging in age from the Ordovician in the Amadeus Basin to Late Cretaceous- Early Tertiary sources in the Bass and Gippsland basins. The carbon isotopic composition of organic matter, approximated using the δ13C of iso-butane, shows a progressive enrichment in 13C with decreasing source age, together with marine source rocks for gas being isotopically lighter than those from land plant sources. The Permian was a time when organic matter was enriched in 13C and isotopically uniform on a regional scale.Secondary, in-reservoir alteration has played a major role in the modification of Australian gas accumulations. Thus, biodegradation, prominent in the Bowen/Surat, Browse, Carnarvon and Gippsland basins, is found in both hydrocarbon and non-hydrocarbon gases. This is recognised by an increase in gas dryness, elevated isoalkane to n-alkane ratio, differential increase in δ13C of the individual wet gas components, a decrease in δ13C of methane and a reduction in CO2 content concomitant with enrichment in 13C. Evidence of water-washing has been identified in accumulations in the Bonaparte and Cooper/Eromanga basins, resulting in an increase in the wet gas content. Seal integrity is also a major risk for the preservation of natural gas accumulations, although its effect on gas composition is only evident in extreme cases, such as the Amadeus Basin, where preferential leakage of methane in the Palm Valley field has resulted in the residual methane becoming enriched in 13C.The greater mobility of gas within subsurface rocks can have a detrimental effect on oil composition whereby gas-stripping of light hydrocarbons is common amongst Australian oil accumulations. Alternatively, the availability of gas, derived from a source rock common to or different from oil, was likely to have been a prime factor controlling the regional distribution of oil, whereby mixing of both results in increased oil mobility and can lead to a greater access to the number and types of traps in the subsurface.

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Butkus, Donatas, Gendrutis Morkūnas, and Laima Pilkyte. "IONIZING RADIATION IN BUILDINGS: SITUATION AND DEALING WITH PROBLEMS." JOURNAL OF ENVIRONMENTAL ENGINEERING AND LANDSCAPE MANAGEMENT 13, no. 2 (June 30, 2005): 103–7. http://dx.doi.org/10.3846/16486897.2005.9636853.

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Among many artificial and natural sources of exposure the exposure which is received indoors is very important both from the point of view of its magnitude and necessity of optimization. Such sources as indoor radon and natural radionuclides in construction materials are the most significant ones. The survey results of national indoor radon show that its concentrations might be rather high in some regions. Construction materials can be a significant source of indoor radon, however, in Lithuania external exposure due to radionuclides in these materials is much more important. Very often natural exposure is neglected from the point of view of radiation protection. Such measures as raising of public awareness, application of radiation protection and construction‐related regulations, remedial measures for radon indoors should be taken in solving the problem. Necessity of optimization of protection from radiation indoors is emphasized.

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Wart, Megan, Evan Simpson, and Marek Flaska. "Piezoelectric Materials Under Natural and Man-Made Radiation: The Potential for Direct Radiation Detection." EPJ Web of Conferences 170 (2018): 01020. http://dx.doi.org/10.1051/epjconf/201817001020.

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Radiation detection systems used for monitoring long term waste storage need to be compact, rugged, and have low or no power requirements. By using piezoelectric materials it may be possible to create a reliable self-powered radiation detection system. To determine the feasibility of this approach, the electrical signal response of the piezoelectric materials to radiation must be characterized. To do so, an experimental geometry has been designed and a neutron source has been chosen as described in this paper, which will be used to irradiate a uranium foil for producing fission fragments. These future experiments will be aimed at finding the threshold of exposure of lead zirconate titanate (PZT) plates needed to produce and electrical signal. Based on the proposed experimental geometry the thermal neutron beam-line at the Breazeale Reactor at The Pennsylvania State University will be used as the neutron source. The uranium foil and neutron source will be able to supply a maximum flux of 1.5e5 fission fragments/second*cm2 to each of the PZT plates.

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Baranov, Boris, Aleksandr Sokolov, and Yuri Boltenko. "Structuring meat systems using natural biopolymers." BIO Web of Conferences 30 (2021): 01005. http://dx.doi.org/10.1051/bioconf/20213001005.

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The features of the structure and properties of raw materials, which are a source of biopolymers of natural origin are presented. The main focus of the theoretical part is paid to the study of the process of structuring of biopolymers (proteins and polysaccharides). Practical approbation was carried out on the example of meat-containing meat and meat chopped products and semi-finished products.

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Klein, Samuel, Henrique Fernandes, and Hans-Georg Herrmann. "Estimating Thermal Material Properties Using Solar Loading Lock-in Thermography." Applied Sciences 11, no. 7 (March 31, 2021): 3097. http://dx.doi.org/10.3390/app11073097.

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This work investigates the application of lock-in thermography approach for solar loading thermography applications. In conventional lock-in thermography, a specimen is subjected to a periodically changing heat flux. This heat flux usually enters the specimen in one of three ways: by a point source, a line source or an extended source (area source). Calculations based on area sources are particularly well suited to adapt to solar loading thermography, because most natural heat sources and heat sinks can be approximated to be homogenously extended over a certain region of interest. This is of particular interest because natural heat phenomena cover a large area, which makes this method suitable for measuring large-scale samples. This work investigates how the extended source approximation formulas for determining thermally thick and thermally thin material properties can be used in a naturally excited setup, shows possible error sources, and gives quantitative results for estimating thermal effusivity of a retaining wall structure. It shows that this method can be used on large-scale structures that are subject to natural outside heating phenomena.

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Ramasubramani, R., and K. Gunasekaran. "Sustainable Alternate Materials for Concrete Production from Renewable Source and Waste." Sustainability 13, no. 3 (January 24, 2021): 1204. http://dx.doi.org/10.3390/su13031204.

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Natural resources are being continuously extracted for the production of concrete which leads to degradation of the ecosystem. This is also a challenge for sustainability to save Nature. This study seeks to identify a suitable replacement material for river sand and stone aggregate for the sustainable utilization of renewable sources. Manufactured sand (M-sand) from industrial by-products and coconut shell (CS), an agricultural waste, are the resources selected as replacement materials for sustainability. This study uses M-sand as fine aggregate and CS coarse aggregate in place of river sand (R-sand) and crushed stone aggregate (CSA) for concrete production, respectively. To prove that M-sand and CS are sustainable alternate materials, this study focused on the microstructural characteristics on concrete constituents and CS aggregate and also conducted on concrete produced using R-sand, M-sand and CS. Also, this study focused on the microstructural characteristics and properties of conventional concrete (CC) and coconut shell concrete (CSC) produced using both R-sand and M-sand. Since this study aims to find sustainable alternative materials for R-sand and CSA by M-sand and CS, its properties are studied and compared since microstructural characterization is very significant for concrete compatibility. Microstructural studies revealed that the use of M-sand does not affect the microstructural properties of concrete compared to R-sand concrete and rather it improves the strength of concrete. A similar same trend was observed when CS was used with M-sand compared to CS used with R-sand. Hence, this study strongly suggests that the use of M-sand in its place of R-sand and CS in its place of CSA are sustainable alternatives for the production of concrete so that natural resources can be saved and hence sustainability could be sustained.

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Ferrara, Carmen, and Giovanni De Feo. "Environmental Assessment of the Recycled Paper Production: The Effects of Energy Supply Source." Sustainability 13, no. 9 (April 26, 2021): 4841. http://dx.doi.org/10.3390/su13094841.

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The main aim of the study was to assess the environmental performance, through the application of the life cycle assessment, of a recycled paper production process focusing on the energy aspect. The production process occurred in a paper mill that produces packaging paper using paper and cardboard from source separation of municipal solid waste as raw materials. Two scenarios (S1 and S2) were defined by their energy supply sources. A cogeneration (CHP) system using natural gas for the combined production of thermal and electric energy was the source in S1. The Italian electricity grid (using the Italian country mix) and a natural gas boiler were the separate sources for electric and thermal energy, respectively, in S2. Finally, in order to evaluate the environmental effects on the results of the study about the variation in the natural gas supply source, four alternative Italian import mixes (M1, M2, M3, and M4) were defined by varying the contribution of the supplier countries. The environmental impacts were evaluated with ReCiPe 2016 (H) using both midpoint and endpoint approaches. The results showed that for both the scenarios, the energy consumption was the main cause of impacts mainly because of the natural gas contribution. The presence of the cogeneration (CHP) system generated significant environmental benefits compared with the use of energy provided by more conventional sources. The production and use of chemicals as well as the disposal of waste produced during the paper production were other environmental hotspots. The variation in the composition of the Italian import mix of natural gas, in terms of the supplier country’s contribution, had a significant influence on the results. The import of natural gas from Russia was the most impactful option. Since Russia is the country that contributes to the Italian import mix the most, in the next years, the use of natural gas in Italy could become increasingly impactful. Therefore, the replacement of natural gas with renewable sources is an urgent priority.

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Fratzl, Peter. "Biomimetic materials research: what can we really learn from nature's structural materials?" Journal of The Royal Society Interface 4, no. 15 (March 6, 2007): 637–42. http://dx.doi.org/10.1098/rsif.2007.0218.

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Nature provides a wide range of materials with different functions and which may serve as a source of bio-inspiration for the materials scientist. The article takes the point of view that a successful translation of these ideas into the technical world requires more than the observation of nature. A thorough analysis of structure-function relations in natural tissues must precede the engineering of new bio-inspired materials. There are, indeed, many opportunities for lessons from the biological world: on growth and functional adaptation, about hierarchical structuring, on damage repair and self-healing. Biomimetic materials research is becoming a rapidly growing and enormously promising field. Serendipitous discovery from the observation of nature will be gradually replaced by a systematic approach involving the study of natural tissues in materials laboratories, the application of engineering principles to the further development of bio-inspired ideas and the generation of specific databases.

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Xin, Shihe, Marie‐Christine Duluc, François Lusseyran, and Patrick Le Quéré. "Numerical simulations of natural convection around a line‐source." International Journal of Numerical Methods for Heat & Fluid Flow 14, no. 7 (October 2004): 830–50. http://dx.doi.org/10.1108/09615530410546245.

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Veerapandian, Mekala, Subramaniyan Ramasundaram, Peter Jerome, Gayathri Chellasamy, Saravanan Govindaraju, Kyusik Yun, and Tae Hwan Oh. "Drug Delivery Application of Functional Nanomaterials Synthesized Using Natural Sources." Journal of Functional Biomaterials 14, no. 8 (August 15, 2023): 426. http://dx.doi.org/10.3390/jfb14080426.

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Nanomaterials (NMs) synthesized from natural sources have been attracting greater attention, due to their intrinsic advantages including biocompatibility, stimuli-responsive property, nontoxicity, cost-effectiveness, and non-immunogenic characteristics in the biological environment. Among various biomedical applications, a breakthrough has been achieved in the development of drug delivery systems (DDS). Biocompatibility is necessary for treating a disease safely without any adverse effects. Some components in DDS respond to the physiological environment, such as pH, temperature, and functional group at the target, which facilitates targeted drug release. NM-based DDS is being applied for treating cancer, arthritis, cardiovascular diseases, and dermal and ophthalmic diseases. Metal nanomaterials and carbon quantum dots are synthesized and stabilized using functional molecules extracted from natural sources. Polymers, mucilage and gums, exosomes, and molecules with biological activities are directly derived from natural sources. In DDS, these functional components have been used as drug carriers, imaging agents, targeting moieties, and super disintegrants. Plant extracts, biowaste, biomass, and microorganisms have been used as the natural source for obtaining these NMs. This review highlights the natural sources, synthesis, and application of metallic materials, polymeric materials, carbon dots, mucilage and gums, and exosomes in DDS. Aside from that, challenges and future perspectives on using natural resources for DDS are also discussed.

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Ma, Ariel, Jian Yu, and William Uspal. "Generating Electricity from Natural Evaporation Using PVDF Thin Films Incorporating Nanocomposite Materials." Energies 14, no. 3 (January 24, 2021): 585. http://dx.doi.org/10.3390/en14030585.

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Natural evaporation has recently come under consideration as a viable source of renewable energy. Demonstrations of the validity of the concept have been reported for devices incorporating carbon-based nanocomposite materials. In this study, we investigated the possibility of using polymer thin films to generate electricity from natural evaporation. We considered a polymeric system based on polyvinylidene fluoride (PVDF). Porous PVDF films were created by incorporating a variety of nanocomposite materials into the polymer structure through a simple mixing procedure. Three nanocomposite materials were considered: carbon nanotubes, graphene oxide, and silica. The evaporation-induced electricity generation was confirmed experimentally under various ambient conditions. Among the nanocomposite materials considered, mesoporous silica (SBA-15) was found to outperform the other two materials in terms of open-circuit voltage, and graphene oxide generated the highest short-circuit current. It was found that the nanocomposite material content in the PVDF film plays an important role: on the one hand, if particles are too few in number, the number of channels will be insufficient to support a strong capillary flow; on the other hand, an excessive number of particles will suppress the flow due to excessive water absorption underneath the surface. We show that the device can be modeled as a simple circuit powered by a current source with excellent agreement between the theoretical predictions and experimental data.

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Linssen, Thierry, Pegie Cool, Mohammed Baroudi, Kristof Cassiers, Etienne F. Vansant, Oleg Lebedev, and Joseph Van Landuyt. "Leached Natural Saponite as the Silicate Source in the Synthesis of Aluminosilicate Hexagonal Mesoporous Materials." Journal of Physical Chemistry B 106, no. 17 (May 2002): 4470–76. http://dx.doi.org/10.1021/jp015578p.

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Zienkiewicz-Strzalka, Malgorzata, Stanislaw Pikus, Malgorzata Skibinska, Magdalena Blachnio, and Anna Derylo-Marczewska. "The Structure of Ordered Mesoporous Materials Synthesized from Aluminum Phyllosilicate Clay (Bentonite)." Molecules 28, no. 6 (March 11, 2023): 2561. http://dx.doi.org/10.3390/molecules28062561.

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This paper reports the synthesis and structural analysis of mesoporous silica materials with the use of aluminum phyllosilicate clay (bentonite) as an alternative silica source. In the proposed synthesis, bentonite, as natural aluminosilicate, was used instead of commercially available and quite expensive tetraethyl orthosilicate (TEOS) silica source. The objective of the research study was to determine the effect of aluminum loading in the mesoporous silica body for ordering structure, porosity, and potential sorption capacity to thorium ions. The unique direction developed in this procedure is focused on preparing advanced materials from natural sources with their own desired functionality and general availability. The applied procedure based on the classic, one-step synthesis of SBA-15 silicates was modified by gradually increasing the bentonite amount with simultaneous reduction of the TEOS content. The structural and morphological characterization, as well as evaluation of the porous structure of the obtained materials, was performed using powder wide-angle X-ray diffraction (XRD), small-angle scattering (SAXS), transmission and scanning electron microscopy (TEM, SEM), low-temperature nitrogen adsorption–desorption methods and potentiometric titration. The new, cost-effective composites for the removal of Th(IV) ions are proposed. The synergistic effect of expanding the porous surface using bentonite as a silica precursor and the presence of thorium-binding groups (such as Al2O3) is indicated.

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Iwata, K., A. Yamada, P. Fons, K. Matsubara, and S. Niki. "Natural ordering of ZnO1−xSex grown by radical source MBE." Journal of Crystal Growth 251, no. 1-4 (April 2003): 633–37. http://dx.doi.org/10.1016/s0022-0248(02)02206-6.

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De Araújo Costa, Dimítri, Nuno Gomes, Harold Cantallo, and Carlos Antunes. "NATURAL HISTORY MUSEUMS." ENVIRONMENTAL SMOKE, Special Issue (December 31, 2021): 24–28. http://dx.doi.org/10.32435/envsmoke/xibesymp.4.

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Society in general is distant from scientific culture, it is required to bring scientific knowledge closer to the population. In this context, an effective and attractive way for scientific dissemination is the establishment of natural history museums, which are institutions of knowledge, displaying the past. Natural history museums have the natural world as their object of study; and their collections may contain the most diverse types of materials (local and/or from various parts of the world), such as zoological, botanical, geological, archaeological, among others. Scientific collections are the largest and most important source of authoritative biodiversity data, contributing to studies of biodiversity composition, evolutionary (morphological and genetic), biogeographical, phenological, as well as geological. The materials present in these collections may serve for temporal comparison, being useful to produce predictive models. Likewise, they have a fundamental role in safeguarding type specimens, i.e. the first organisms identified to describe and name a new species. In addition, there is the component available to visitors in general, in order to raise public awareness on the preservation of the local fauna and flora and of other places in the world. In this way, the museums serve both the academic-scientific public and visitors who come to these sites for recreational purposes. It is intended to promote, in Vila Nova de Cerveira, the Natural History Museum of the Iberian Peninsula - NatMIP (“Museu de História Natural da Península Ibérica”), which intends to collect materials for scientific purposes, mainly Iberian.

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Zhang, Enhui, Weimin Li, Ningli Wang, Gaiqing Zhao, Rui Ma, Junyang Dong, and Xiaobo Wang. "Peptide from natural source as ecofriendly aqueous lubricant additive." Tribology International 178 (February 2023): 108082. http://dx.doi.org/10.1016/j.triboint.2022.108082.

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Grishin, Evgeniy S. "Reference Maps on Building Materials for the Western Front of the Russian Army (1915–1918)." Historical Geography Journal 1, no. 4 (2022): 78–81. http://dx.doi.org/10.58529/2782-6511-2022-1-4-78-81.

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The article gives a description of a special group of the cartographic sources of the First World War period — building materials maps. The methods for compiling maps and the source materials for them are revealed. The maps were elaborated by the “Commission on Raw and Chemical Materials” having been a part of the “Military Technical Assistance Committee”, in order to facilitate the material support of Russian troops on the Western Front with various natural materials that could be used for the fortification and construction works, as well as for laying the communication lines. In total, at least 11 sheets of maps of similar content are known to have been compiled. Using the sheet № 14 for the Vilna area as an example, the main features of the considered group of sources are revealed: structure, graphic design, main sections of the explanatory note, content and legend of the map itself. Various aspects of the significance of the source are indicated: it is not only a carrier of information about the natural resources of individual regions of the Russian Empire, but also a remarkable example of the preparation of operational cartographic information through the use and adaptation of the maps by I. A. Strel’bitsky. The maps reflect not only the extent of prospecting for the regions’ natural resources and their geological knowledge, but also contain valuable information on their exploitation; the same can be put down to the explanatory note, which, in addition to the specified information, contains data on water resources and their use. It should be noted that the maps on building materials practically have not been cited either in special studies on the history of the First World War, or in works devoted to the history of cartography.

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Ellenberger, Alessandro, Milton Luiz Polli, Elaine Azevedo, and Caroline Rodrigues Pereira de Paula. "Drilling of natural fiber-reinforced based polyurethane foam composite." Journal of Composite Materials 56, no. 6 (January 29, 2022): 899–909. http://dx.doi.org/10.1177/00219983211059581.

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The combination of natural fibers and renewable source matrices is an option to replace materials from non-renewable sources used in the manufacture of composites. One example is the use of pinus sawdust and sisal fibers together with a matrix of polyurethane (PU) foam derived from vegetable oils. For the application of composites in sectors such as building or furniture industry, one of the necessary processes is drilling, which allows assembling through different fastening systems. The aim of this work is to investigate the drilling process of the composites of PU foam derived from vegetable oils matrix with only pinus sawdust and hybrid pinus sawdust and sisal fibers taking into account surface damages of the holes and temperature generated during the process. Results showed that drilling parameters influence on the generation of damages mainly at the edges of the holes. Lower cutting speed and feed rate were most appropriate for drilling these types of composites, and temperatures generated during drilling showed relationship with the generation of damages.

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Jean, Aurélien P., Craig Adams, Mario A. Medina, and Frédéric Miranville. "Natural Materials for Thermal Insulation: Mulch and Lava-Rock Characterizations." Applied Mechanics and Materials 705 (December 2014): 8–13. http://dx.doi.org/10.4028/www.scientific.net/amm.705.8.

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This paper reports on the thermal characterization, via the thermal conductivity, of natural materials, such as mulch and lava rock and their usefulness as building insulation. Experiments were carried out using a scale one monitored wall (i.e. heat flux and temperature sensors) exposed to a heating source on one side and to an air conditioned space on the other. The wall system was composed of an 8.85 cm thick cavity, where the mulch and lava rock were placed. The cavity was enclosed between two layers of pine wood (40 mm thick each). After the experiments and statistical data manipulation, the estimated thermal conductivity of the materials were 0.48 ± 0.001 W.m-1.K-1 and 0.129 ± 0.003 W.m-1.K-1 for mulch and lava-rock, respectively. That is, mulch has a thermal conductivity comparable to that of bulk hemp while lava rock has a thermal conductivity comparable to that of hemp brick. These values indicate the usefulness of mulch, compared to the impracticality of using lava-rocks materials for building insulation.

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WOODS, ANDREW W., C. P. CAULFIELD, and JEREMY C. PHILLIPS. "Blocked natural ventilation: the effect of a source mass flux." Journal of Fluid Mechanics 495 (November 25, 2003): 119–33. http://dx.doi.org/10.1017/s0022112003005627.

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Puskas, Judit E., and Carin A. Helfer. "NATURAL RUBBER BIOSYNTHESIS: STILL A MYSTERY." Rubber Chemistry and Technology 91, no. 4 (October 1, 2018): 683–700. http://dx.doi.org/10.5254/rct.18.81529.

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ABSTRACT Currently, Hevea brasiliensis (the Brazilian rubber tree) is the only commercially available source of natural rubber (NR) for use in many products, which vary from tires to medical products such as adhesive bandages. H. brasiliensis NR is used in these products because after vulcanization, superior properties, which include elasticity, abrasion resistance, and efficient heat dispersion, result. Issues, such as increasing demand and risk of a single source, make a synthetic (manmade) NR an attractive option. However, after years of research efforts, the exact structure of high-molecular-weight NR is still unproven, and a synthetic NR with similar properties to H. brasiliensis NR still has not been developed. To create a replacement synthetic rubber for H. brasiliensis NR, we believe an understanding of NR biosynthesis is necessary. We present a view of NR biosynthesis from a polymer chemistry viewpoint that is based on insight into the mechanism and kinetics of living carbocationic polymerization.

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Shukla, Dhara, and Padma S. Vankar. "Natural Dyeing with Black Carrot: New Source for Newer Shades on Silk." Journal of Natural Fibers 10, no. 3 (July 3, 2013): 207–18. http://dx.doi.org/10.1080/15440478.2012.757031.

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Kadimova, M. Sh. "ON THE CONSTITUTIONAL FOUNDATIONS OF LEGAL REGULATION OF SOLID WASTE MANAGEMENT IN THE REPUBLIC OF DAGESTAN." Law Нerald of Dagestan State University 38, no. 2 (2021): 44–48. http://dx.doi.org/10.21779/2224-0241-2021-38-2-44-48.

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Within the framework of this article, the problem of processing production and consumption waste is considered, which is so urgent today, both for our republic and for Russia as a whole. Recycling is necessary, firstly, because the resources of many materials on Earth are limited and cannot be replenished. Secondly, once released into the environment, materials most often become pollutants. Third, waste and end-of-life products are often a cheaper source of many substances and materials than natural sources

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Baroi, Anda Maria, Elwira Sieniawska, Łukasz Świątek, and Irina Fierascu. "Grape Waste Materials—An Attractive Source for Developing Nanomaterials with Versatile Applications." Nanomaterials 13, no. 5 (February 23, 2023): 836. http://dx.doi.org/10.3390/nano13050836.

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In the last decade, researchers have focused on the recycling of agro-food wastes for the production of value-added products. This eco-friendly trend is also observed in nanotechnology, where recycled raw materials may be processed into valuable nanomaterials with practical applications. Regarding environmental safety, replacing hazardous chemical substances with natural products obtained from plant wastes is an excellent opportunity for the “green synthesis” of nanomaterials. This paper aims to critically discuss plant waste, with particular emphasis on grape waste, methods of recovery of active compounds, and nanomaterials obtained from by-products, along with their versatile applications, including healthcare uses. Moreover, the challenges that may appear in this field, as well as future perspectives, are also included.

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Wang, Yifeng, Jian Li, Jianfa Chen, and Chengshan Li. "Quantitative identification and research of mixed-source natural gas-example of natural gas in Jingbian gas field." World Journal of Engineering 11, no. 2 (June 1, 2014): 147–56. http://dx.doi.org/10.1260/1708-5284.11.2.147.

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It is shown in natural gas proportion mixing experiments that a mixed-source natural gas is the physical combination of end member gas. Both the carbon and hydrogen isotopes in the mixed-source natural gas can be expressed by the weighted average of corresponding components content and isotopes of end member gas. Under certain geological setting, the selection of end member gas is the key to mixed-source ratio calculation. Then, it's better to estimate the mixed-source ratio with δ13C1 and component data according to the weighted average calculation formula. The analysis on natural gas geochemistry characteristics show that the natural gas extracted from Jingbian Gas Field in the Ordos Basin is mainly an upper Paleozoic coal-derived gas. In the analysis of geological conditions for reservoir forming and characteristics of natural gas, natural gas from Longtan 1 Well and Tao 6 Well were selected as the end member gases of lower Paleozoic oil-type gas and upper Paleozoic coal-type gas respectively to calculate the mixed-source ratio of natural gas in Jingbian Gas Field. The ratio of upper Paleozoic coal-derived gas mostly accounts for over 70% and its average ratio reaches 81%. Therefore, the exploration of natural gas of Ordos Basin should be focused on the upper palaeozoic coal source rock, and attention should be paid to the matching of coal source rock in the exploration of weathered crust gas deposit.

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Phan, T. T. Q., T. T. Le, and K. Dewettinck. "Effect of milk fat globule membrane materials on the crystallization behaviour in dairy recombined cream." Food Research 4, no. 5 (April 26, 2020): 1412–20. http://dx.doi.org/10.26656/fr.2017.4(5).092.

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Milk fat globule membrane (MFGM) fragments were isolated from reconstituted buttermilk (BM-MFGM) and from buttermilk whey (whey-MFGM) and used to make recombined cream. Besides, the commercial dairy ingredient, Lacprodan® PL20, a material rich in milk polar lipids and proteins, was used as another MFGM source. Recombined cream was prepared by homogenizing 35% (w/w) anhydrous milk fat into an aqueous phase containing individual BM-MFGM, Whey-MFGM, Lacprodan® PL20, or buttermilk powder (BMP) or a mixture of MFGM materials and BMP (4:6, w/w). The effect of MFGM on the fat crystallization behaviour, shear-induced partial coalescence was investigated and compared to those of natural cream and recombined cream made with BMP. It was found that the physicochemical properties of recombined cream were strongly affected by the MFGM source. Shear-induced partial coalescence of WheyMFGM40 was slower compared to that of natural cream. Amongst the four emulsifier materials used in this study, Whey-MFGM showed a similar crystallization behaviour to natural cream.

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TUDORACHE, V., M. MINESCU, N. ILIAS, and I. OFFENBERG. "FROM NATURAL GAS TO GREEN HYDROGEN." Neft i gaz, no. 4 (August 30, 2021): 125. http://dx.doi.org/10.37878/2708-0080/2021-4.09.

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Since hydrogen usually exists on Earth as part of a compound, it has to be synthesized in specific processes in order to be used as a product or energy source. This can be achieved by different technical methods, and various primary energy sources, – both fossil and renewable fuels, in solid, liquid or gaseous form, – can be used in these technical production processes. Hydrogen has only a very low volumetric energy density, which means that it has to be compressed for storage and transportation purposes. The most important commercial storage method, – especially for end users, – is the storage of hydrogen as a compressed gas. A higher storage density can be achieved by hydrogen liquefaction. Novel materials-based storage media (metal hydrides, liquids or sorbents) are still at the research and development stage. The storage of hydrogen (for example, to compression or liquefaction) requires energy; work is, in present, on more efficient storage methods. Unlike electricity, hydrogen can be successfully stored in large amounts for extended periods of time. For example, in long-term underground storage facilities hydrogen can play an important role as a buffer store for electricity from surplus provided by renewable energies. At present, pure hydrogen is generally transported by lorry in pressurize gas containers, and in some cases also in cryogenic liquid tanks. Moreover, local/regional hydrogen pipeline networks are available in some locations. Another solution for storage and transportation are Liquid Organic Hydrogen Carriers (LOHC) that can use long pipe networks and ships. In the near future, the natural gas supply infrastructure or oil (transportation pipelines and underground storage facilities) could also be used, in specific conditions, for the storage and transportation of pure or blended hydrogen with methane. This could be essential for transition because most important primary energy source for hydrogen production currently is natural gas, at 71%, followed by oil, coal and electricity (as a secondary energy resource). Steam reforming (from natural gas) is the most commonly used method for hydrogen production. In this new light, the article explores the trend and prospects for hydrogen, presented in the literature, as a source of energy competing with gas and oil resources in the global energy system of the future.

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Ghazvini Zadeh, E. H., S. Tang, A. W. Woodward, T. Liu, M. V. Bondar, and K. D. Belfield. "Chromophoric materials derived from a natural azulene: syntheses, halochromism and one-photon and two-photon microlithography." Journal of Materials Chemistry C 3, no. 33 (2015): 8495–503. http://dx.doi.org/10.1039/c5tc01459j.

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Katsu, You, Kotaro Kato, Shuji Abe, and Kae Miyazawa. "Seed Source Effects on Germination, Growth, and Yield of Carrots Under Natural Farming." Journal of Horticultural Research 29, no. 2 (October 26, 2021): 117–26. http://dx.doi.org/10.2478/johr-2021-0014.

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Abstract Natural farming is a type of low-input sustainable agricultural system that is characterized by the avoidance of the use of any animal materials. Production of self-produced seeds by farmers is recommended under natural farming environments, with an expectation of improved crop growth and yield. However, there have been no scientific studies that investigated the performance of self-produced seeds under natural farming. This study investigated the germination rate, growth, and yield of carrots (Daucus carota L.) from different seed sources under natural farming. The main experimental factor was the cultivation method: CT – control; CF – conventional farming; NF1 – natural farming with tillage and compost input; and NF2 – natural farming without tillage and compost, and the subfactor was the seed source: OPN – open-pollinated seeds self-produced under natural farming; OPC – open-pollinated seeds produced under conventional farming; and HB – hybrid seeds. The germination rate of OPN seeds was higher than that of other seeds. In addition, root fresh weight and other root parameters of OPN were as high as for HB seeds. This suggests that using self-produced seeds by farmers improves crop performance in a natural farming system.

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Dahibhate, Nilesh Lakshman, Ankush Ashok Saddhe, and Kundan Kumar. "Mangrove Plants as a Source of Bioactive Compounds: A Review." Natural Products Journal 9, no. 2 (March 18, 2019): 86–97. http://dx.doi.org/10.2174/2210315508666180910125328.

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Mangroves are unique coastal forest ecosystem distributed along the tropical and subtropical region of the world. They are evolutionarily adapted to combat against hostile environmental conditions such as low oxygen, high salinity, and temperature. The adaptive features endowed with novel secondary metabolic pathways and bioactive compounds to sustain in harsh conditions. The novel metabolites are a rich source of the wide range of bioactive compounds and natural products. It includes terpenoids, alkaloids, phenolics, saponins, flavonoids, and steroids. The bioactive and natural compounds may serve as therapeutic precursors and industrial raw materials. Terpenes and polyphenols have antiviral, antibacterial, antifungal, antimalarial, anticancer or combination of activities. To date, several mangroves plants were examined and recognized as a potential source of novel natural product for exploitation in medicine. In fact, most of the isolated compounds are novel and showed promising biological activities such as gastroprotective, cytotoxic, antioxidant, antibacterial, antifungal, antiviral, enzyme activation and inhibition, immunosuppressive, anti-inflammatory, antifeedant effects. In the present review, we have compiled the achievements and progress in mangroves natural products research of the last decade.

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Selvaraj, Nivethra, and Dr R. Prathiba Devi. "Eco-friendly natural dyes and their application on printing graphics." Scientific Temper 14, no. 02 (June 6, 2023): 342–46. http://dx.doi.org/10.58414/scientifictemper.2023.14.2.15.

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Natural dyes, which have been pushed to the background by synthetic colours over the past sixty years, have suddenly resurfaced as a source of consumer interest. This is because of the familiarity with potential dangers during the innovation of engineered colors which include utilization of petrochemical-based unrefined components and the brutal substance responses for their combination. The production of engineered colors is energy concentrated with unfriendly effect on climate adding to its contamination. A considerable lot of these colors, particularly the azo-based ones, are viewed as cancer-causing. A brief examination of natural colourants derived from plant sources, their sequence, and the component ingredients responsible for diverse shadings is provided in this foundation, its exercises and impact of various mordants on the tone is talked about. Various classes of mordants utilized for obsession of regular colouration on materials substrated, its instrument and plant sources are likewise examined.

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Zharmenov, Abdurassul, Svetlana Yefremova, Baimakhan Satbaev, Nurgali Shalabaev, Serik Satbaev, Sergey Yermishin, and Askhat Kablanbekov. "Production of Refractory Materials Using a Renewable Source of Silicon Dioxide." Minerals 12, no. 8 (August 12, 2022): 1010. http://dx.doi.org/10.3390/min12081010.

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Organization of environmentally-friendly production of refractory materials based on the principles of cost-effective use of energy and material resources through use of energy-saving technologies and replacement of natural raw materials with industrial and agricultural waste is gaining relevance. Scientists are increasingly interested in creating high-temperature materials using silica of plant origin. Its source is rice husk, a multi-tonnage waste from rice production. Organo-mineral in its nature, rice husk determines the uniqueness of the structure and properties of the materials obtained from it. Use of this waste allows us to produce porous, high-strength silicon carbide refractories with properties corresponding to classical analogs, while benefiting from environmental, economic and technological aspects. The lack of industrial production of refractories using rice husk ash, despite the positive results of scientific research, indicates insufficient study of the issue with certain gaps in this area. This review is intended to help researchers to identify existing problems and outline further actions necessary to ensure that the scientific results are implemented in production.

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Journal articles on the topic 'Natural source materials'

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