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Journal articles on the topic 'Water modification'
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1
Lédion, J., S. Mebrouk, C. Seznec, and H. Jullien. "Modification du pouvoir entartrant de l'eau par chauffage micro-ondes." Journal européen d’hydrologie 30, no. 1 (1999): 13–33. http://dx.doi.org/10.1051/water/19993001013.
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Moeller, Hanne B., Emma T. B. Olesen, and Robert A. Fenton. "Regulation of the water channel aquaporin-2 by posttranslational modification." American Journal of Physiology-Renal Physiology 300, no. 5 (2011): F1062—F1073. http://dx.doi.org/10.1152/ajprenal.00721.2010.
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The cellular functions of many eukaryotic membrane proteins, including the vasopressin-regulated water channel aquaporin-2 (AQP2), are regulated by posttranslational modifications. In this article, we discuss the experimental discoveries that have advanced our understanding of how posttranslational modifications affect AQP2 function, especially as they relate to the role of AQP2 in the kidney. We review the most recent data demonstrating that glycosylation and, in particular, phosphorylation and ubiquitination are mechanisms that regulate AQP2 activity, subcellular sorting and distribution, degradation, and protein interactions. From a clinical perspective, posttranslational modification resulting in protein misrouting or degradation may explain certain forms of nephrogenic diabetes insipidus. In addition to providing major insight into the function and dynamics of renal AQP2 regulation, the analysis of AQP2 posttranslational modification may provide general clues as to the role of posttranslational modification for regulation of other membrane proteins.
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Ringman, Rebecka, Greeley Beck, and Annica Pilgård. "The Importance of Moisture for Brown Rot Degradation of Modified Wood: A Critical Discussion." Forests 10, no. 6 (2019): 522. http://dx.doi.org/10.3390/f10060522.
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The effect of wood modification on wood-water interactions in modified wood is poorly understood, even though water is a critical factor in fungal wood degradation. A previous review suggested that decay resistance in modified wood is caused by a reduced wood moisture content (MC) that inhibits the diffusion of oxidative fungal metabolites. It has been reported that a MC below 23%–25% will protect wood from decay, which correlates with the weight percent gain (WPG) level seen to inhibit decay in modified wood for several different kinds of wood modifications. In this review, the focus is on the role of water in brown rot decay of chemically and thermally modified wood. The study synthesizes recent advances in the inhibition of decay and the effects of wood modification on the MC and moisture relationships in modified wood. We discuss three potential mechanisms for diffusion inhibition in modified wood: (i) nanopore blocking; (ii) capillary condensation in nanopores; and (iii) plasticization of hemicelluloses. The nanopore blocking theory works well with cell wall bulking and crosslinking modifications, but it seems less applicable to thermal modification, which may increase nanoporosity. Preventing the formation of capillary water in nanopores also explains cell wall bulking modification well. However, the possibility of increased nanoporosity in thermally modified wood and increased wood-water surface tension for 1.3-dimethylol-4.5-dihydroxyethyleneurea (DMDHEU) modification complicate the interpretation of this theory for these modifications. Inhibition of hemicellulose plasticization fits well with diffusion prevention in acetylated, DMDHEU and thermally modified wood, but plasticity in furfurylated wood may be increased. We also point out that the different mechanisms are not mutually exclusive, and it may be the case that they all play some role to varying degrees for each modification. Furthermore, we highlight recent work which shows that brown rot fungi will eventually degrade modified wood materials, even at high treatment levels. The herein reviewed literature suggests that the modification itself may initially be degraded, followed by an increase in wood cell wall MC to a level where chemical transport is possible.
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Shi, Jingying, Xuefei Zhao, and Can Li. "Surface Passivation Engineering for Photoelectrochemical Water Splitting." Catalysts 13, no. 2 (2023): 217. http://dx.doi.org/10.3390/catal13020217.
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Surface passivation engineering is an imperative way to improve photoelectrode performance for photoelectrochemical (PEC) water splitting. To the best of our knowledge, it has never been systematically reviewed in a feature article. In this review, we summarize various passivation materials and their preparation, characterizations by PEC measurements and some related spectral technologies. We highlight the features of the passivation effect that separate it from other modifications, such as cocatalyst decoration, and we demonstrate significant progress in combining surface passivation engineering with other interfacial modification strategies for the rational design of photoelectrodes. Ideas for future research on surface passivation modification for improving the performance of photoelectrodes are also proposed.
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Wan, Xiaokang, Fujun Niu, Jinzhan Su, and Liejin Guo. "Enhanced photoelectrochemical water oxidation of bismuth vanadate via a combined strategy of W doping and surface RGO modification." Physical Chemistry Chemical Physics 18, no. 46 (2016): 31803–10. http://dx.doi.org/10.1039/c6cp06233d.
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Budiarti, Gita Indah, Lukhi Mulia Shitophyta, Ndaru Okvitarini, Vinna Fajarwaty, and Ayu Damayanti. "Modification blanching process of potato flour using hydrogen rich water." Reaktor 20, no. 4 (2020): 161–65. http://dx.doi.org/10.14710/reaktor.20.4.161-165.
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The chemical composition of potatoes includes carbohydrates, protein, fiber, vitamins, and minerals. The composition of vitamins and minerals in potatoes is higher than wheat flour. Brownish color in potato flour has reduced consumer's interest, so it needs to be modified to improve the color and physicochemical properties of flour. Researchers are trying to modify the blanching process using hydrogen-rich water. Because hydrogen-rich water has antioxidants that can prevent the browning process (oxidation) potato flour, cheaper, safer, and healthier than chemical compounds. The purpose of this study was to optimize the blanching process for potato flour modification. Variation of the process used is soaking time at 30, 45, 60, 75, and 90 minutes. The optimal results of water content, ash content, reducing sugar content, protein, color, and swelling power were obtained at 75 minutes are 6.7%, 2.68%, 0.26%, 7.1%, 81.17, and 7 g/g. The quality of the modified potato flour met the physicochemical parameters of the flour according to the SNI standard for flour, except ash content. The quality of potato flour produced almost equals as the quality of wheat flour, so it needs to be considered as a substitute for wheat flour and is friendly for diabetics.Keywords: potatoes, modified flour, physicochemical properties, wheat
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Hakak, Aaliya Rafiq, Shubham Bankhele, and Rajat Malpani P. S. Bhamare. "Modification and Advancements in the Traditional Method of Water Purification." International Journal of Trend in Scientific Research and Development Volume-2, Issue-6 (2018): 1467–70. http://dx.doi.org/10.31142/ijtsrd14426.
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Վարդանյան, Վ․ Պ․, та Տ․ Գ․ Մկրտչյան. "ԵՐԵՎԱՆ ՔԱՂԱՔԻ ԵՐԿՐԱԲԱՆԱԿԱՆ ՄԻՋԱՎԱՅՐԻ ՓՈՓՈԽՈՒԹՅՈՒՆԸ ՏԵԽՆԱԾԻՆ ԳՈՐԾՈՆՆԵՐԻ ՀԵՏԵՎԱՆՔՈՎ". Proceedings of the YSU C: Geological and Geographical Sciences 45, № 2 (225) (2011): 27–32. http://dx.doi.org/10.46991/pysu:c/2011.45.2.027.
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In this article natural conditions of Yerevan City, modification of geological environment under the influence of technogenic impacts are considered. Development of industry and construction causes uncontrolled modifications of ground water regime, as well as activation of landslides, collapses, subsidence of soils. Zoning of territory of the city on modification of geological environment has been carried out. In greatly altered territories conducting of drainage channels, restoration of irrigative, water supply-sewer nets, meliorating of waste disposal territories are recommended.
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Najib, Muchammad Ilham, Felicia Hestiawan, Amelia Pratiwi, and Lintang Bagas Pangayom. "Minimizing Process Water and Energy Consumption in Styrene Production by Ethylbenzene Dehydrogenation." Journal of Chemical Engineering Research Progress 1, no. 2 (2024): 132–41. https://doi.org/10.9767/jcerp.20272.
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Styrene is a crucial unsaturated aromatic monomer with a wide range of industrial applications. Styrene production faces several problems where the water supply and energy usage are keep increasing. Process modifications were implemented to minimize process water and to optimize the energy consumption. The modification uses Aspen HYSYS simulation by replacing coolers and heaters with heat exchanger and implementing water recycling system. Aspen HYSYS simulations show these changes reduce water usage by 89.8% and significantly decrease energy consumption up to 54.69%. This modification shows the water and energy usage have been significantly reduced than the basic process. Copyright © 2024 by Authors, Published by Universitas Diponegoro and BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).
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Liu, Lei, Ning Liu, Biaohua Chen, Chengna Dai, and Ning Wang. "Recent Modification Strategies of MoS2 towards Electrocatalytic Hydrogen Evolution." Catalysts 14, no. 2 (2024): 126. http://dx.doi.org/10.3390/catal14020126.
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Hydrogen production by the electrolysis of water is a green and efficient method, which is of great significance for achieving sustainable development. Molybdenum disulfide (MoS2) is a promising electrocatalyst for hydrogen evolution reaction (HER) due to its high electrochemical activity, low cost, and abundant reserves. In comparison to the noble metal Pt, MoS2 has poorer hydrogen evolution performance in water electrolysis. Therefore, further modifications of MoS2 need to be developed aiming at improving its catalytic performance. The present work summarizes the modification strategies that have been developed in the past three years on hydrogen evolution from water electrolysis by utilizing MoS2 as the electrocatalyst and following the two aspects of internal and external modifications. The former includes the strategies of interlayer spacing, sulfur vacancy, phase transition, and element doping, while the latter includes the heterostructure and conductive substrate. If the current gap in this paper’s focus on modification strategies for electrocatalytic hydrogen evolution in water electrolysis is addressed, MoS2 will perform best in acidic or alkaline media. In addition to that, the present work also discusses the challenges and future development directions of MoS2 catalysts.
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Subroto, Edy, Yana Cahyana, Rossi Indiarto, and Tiara Aray Rahmah. "Modification of Starches and Flours by Acetylation and Its Dual Modifications: A Review of Impact on Physicochemical Properties and Their Applications." Polymers 15, no. 14 (2023): 2990. http://dx.doi.org/10.3390/polym15142990.
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Various modification treatments have been carried out to improve the physicochemical and functional properties of various types of starch and flour. Modification by acetylation has been widely used to improve the quality and stability of starch. This review describes the effects of acetylation modification and its dual modifications on the physicochemical properties of starch/flour and their applications. Acetylation can increase swelling power, swelling volume, water/oil absorption capacity, and retrogradation stability. The dual modification of acetylation with cross-linking or hydrothermal treatment can improve the thermal stability of starch/flour. However, the results of the modifications may vary depending on the type of starch, reagents, and processing methods. Acetylated starch can be used as an encapsulant for nanoparticles, biofilms, adhesives, fat replacers, and other products with better paste stability and clarity. A comparison of various characteristics of acetylated starches and their dual modifications is expected to be a reference for developing and applying acetylated starches/flours in various fields and products.
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Hu, Po, and Paul Wilson. "Code Development in Coupled PARCS/RELAP5 for Supercritical Water Reactor." Science and Technology of Nuclear Installations 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/286434.
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The new capability is added to the existing coupled code package PARCS/RELAP5, in order to analyze SCWR design under supercritical pressure with the separated water coolant and moderator channels. This expansion is carried out on both codes. In PARCS, modification is focused on extending the water property tables to supercritical pressure, modifying the variable mapping input file and related code module for processing thermal-hydraulic information from separated coolant/moderator channels, and modifying neutronics feedback module to deal with the separated coolant/moderator channels. In RELAP5, modification is focused on incorporating more accurate water properties near SCWR operation/transient pressure and temperature in the code. Confirming tests of the modifications is presented and the major analyzing results from the extended codes package are summarized.
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Siedlecka, Beata, and Monika Marchwicka. "Influence of modification of aged spruce wood by in situ polymerization with ethyl methacrylate and methyl acrylate and paraloid B72 on color and water absorption." Annals of WULS, Forestry and Wood Technology 120 (December 28, 2022): 45–56. http://dx.doi.org/10.5604/01.3001.0016.2315.
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Influence of modification of aged spruce wood by in situ polymerization with ethyl methacrylate and methyl acrylate and paraloid B72 on color and water absorption. Wood is hydrophilic in nature, which creates problems such as dimensional instability and susceptibility to biological degradation. By using chemical modification, wood can be refined into new products with improved properties. Such a combination of wood and polymer is called a wood-polymer composite (WPC). The presented work compares the modification of aged wood by two methods. In situ polymerization with ethyl methacrylate and methyl acrylate with modification with Paraloid B72 solution. The determinants of the modifications carried out are percentage weight gain (WPG), color change and water absorption. Unmodified wood aged and unaged were the control samples. Also unaged and modified wood samples were prepared to compare results. The greatest change in color intensity and total color difference after the aging process was recorded for samples modified with Paraloid B72, and after UV light treatment - modified by the in situ polymerization. The in situ-modified samples had the lowest water absorption among aged samples, and Paraloid B72-modified samples had the lowest water absorption among unaged samples. The highest WPG was obtained from the aged samples modified by the in situ polymerization.
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Sonawan, Hery, Panji Saputro, and Iden Muhtar Kurniawan. "Utilization of air conditioner condenser as water heater in an effort to energy conservation." Renewable Energy and Environmental Sustainability 3 (2018): 1. http://dx.doi.org/10.1051/rees/2018001.
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This paper presents an experimental study of utilization of air conditioner condenser as water heater. Modification of existing air conditioner system is an effort to harvest waste heat energy from condenser. Modification is conducted in order to test the system into two mode tests, first mode with one condenser and second mode with two condensers. Harvesting the waste heat from condenser needs a theoretical and practice study to see how much the AC performance changes if modifications are made. It should also be considered how the technique of harvesting waste heat for water heating purposes. From the problem, this paper presents a comparison between AC performance before and after modification. From the experiment, an increase in compressor power consumption is 4.3% after adding a new condenser. The hot water temperature is attained to 69 °C and ready for warm bath. The increase in power consumption is not too significant compared to the attainable hot water temperature. Also seen that the value of condenser Performance Factor increase from 5.8 to 6.25 or by 7.8%.
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Qiao, Liqin, Yao Dong, Hongli Zhou, and Hao Cui. "Effect of Post–Polyketide Synthase Modification Groups on Property and Activity of Polyene Macrolides." Antibiotics 12, no. 1 (2023): 119. http://dx.doi.org/10.3390/antibiotics12010119.
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The biosynthesis of polyene macrolides, which are natural products produced by soil actinomycetes, have been extensively explored, and recent studies have focused on the effects of post–polyketide synthase (PKS) modifications to polyene macrolides on toxicity, water solubility, and antifungal activity. For example, there are interactions between glycosyl, carboxyl, and hydroxyl or epoxy groups generated in the post-PKS modification steps; salt bridges will be formed between carboxylate and ammonium on the mycosamine; and water bridges will be formed between hydroxy and hydroxyl on mycosamine. These interactions will affect their water solubility and substrate-recognition specificity. This review summarizes research related to these post-PKS modification groups and discusses some genetic engineering operation problems and solutions that may be encountered when modifying these post-PKS modification groups. In addition, this review provides a basis for the structural research of polyene macrolide antibiotics and contributes to comprehensive and systematic knowledge, and it may thus encourage researchers to develop novel antifungal drugs with higher therapeutic indexes and medical values.
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Boussahel, Rachdi, Souhila A. Ouldramoul, Djamila Harik, Mohamed Mammar, and Khadija M. Moussaoui. "Valorisation de la sciure de bois par modification chimique dans l'élimination du pesticide 4,4-DDT présent dans l'eau." European journal of water quality 40, no. 1 (2009): 75–93. http://dx.doi.org/10.1051/water/2009006.
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Yu, Wangwang, Rui Qiu, Wen Lei, and Yong Chen. "Effects of Modification on Properties of Wood Flour/PBAT Biocomposites." Polymers 17, no. 5 (2025): 555. https://doi.org/10.3390/polym17050555.
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Wood flour (WF)-reinforced poly (butylene adipate-co-terephthalate) (PBAT) composites were successfully fabricated by injection-molding process after being mixed using an extruder. The effects of fiber modifications, including mercerization, acetylation, as well as coupling agent treatment on the properties of WF/PBAT composites, were studied. The results indicated that all the modifications increased the mechanical properties (e.g., tensile strength, tensile modulus, flexural strength, flexural modulus, elongation at break, and Charpy impact strength) of the composites. After modification, all the composites showed better interfacial bonding, hydrophobicity, and thermal properties compared to the untreated fiber composites; meanwhile, the moisture absorption test showed that all the modified fiber composites exhibited a much lower saturated water absorption rate than untreated ones. WF modification by addition of a coupling agent could improve the properties most obviously, except for the tensile strength, elongation at break, and saturated water absorption rate. By this modification, the tensile modulus, flexural strength, flexural modulus, impact strength, onset temperature during thermal degradation, degree of crystallinity, and water contact angle of the composite were 313.47 MPa, 20.55 MPa, 830.79 MPa, 16.01 kJ/cm2, 367.71 °C, 17.10%, and 101.8°, all increased from those of untreated composites by 17.95%, 30.73%, 87.52%, 35.79%, 61.49%, 25.67 °C, 89.16%, and 6.6°, respectively.
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Terekhov, Roman P., Igor R. Ilyasov, Vladimir L. Beloborodov, et al. "Solubility Enhancement of Dihydroquercetin via “Green” Phase Modification." International Journal of Molecular Sciences 23, no. 24 (2022): 15965. http://dx.doi.org/10.3390/ijms232415965.
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Dihydroquercetin (DHQ) is a promising antioxidant for medical applications. The poor water solubility of this flavanonol at ambient conditions inhibits its implementation in clinical practice as an injectable dosage form. Thus, increasing water solubility is a critical step toward solving this problem. Herein we attempted to deal with this problem via DHQ phase modification while at the same time adhering to the principles of green chemistry as much as possible. Lyophilization is an appropriate method to achieve phase modification in an environment-friendly way. This method was employed to generate new phase modifications of DHQ that were then characterized. Mixtures of water with ethanol or acetonitrile were used as solvents for the preparation of the lyophilizates, DHQE, and DHQA, respectively. The results of dissolution testing of the obtained DHQE and DHQA demonstrated that the lyophilization increased water solubility at least 30-fold times. These new DHQ modifications were studied by scanning electron microscopy, mass-spectrometry, nuclear magnetic resonance spectroscopy, infrared spectroscopy, X-ray powder diffraction, and thermal analysis. Their solid-state phases were confirmed to differ from the initial DHQ substance without any changes in the molecular structure. Both DHQE and DHQA showed as high antioxidant activity as the initial DHQ. These data demonstrate the potential of DHQE and DHQA as active pharmaceutical ingredients for injectable dosage forms.
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Stangierski, J., R. Rezler, H. M. Baranowska, and S. Poliszko. " Effect of enzymatic modification on chicken surimi." Czech Journal of Food Sciences 30, No. 5 (2012): 404–11. http://dx.doi.org/10.17221/451/2011-cjfs.
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The impact of the addition and duration of protein modification with transglutaminase preparation of microbial origin (MTG) of a chicken surimi on its texture, rheological characteristics, water molecular dynamics, and water activity were assessed. Surimi samples were supplemented with 0.3 g/100 g MTG and incubated maximally for about 7 h at the temperature of 15°C. The greatest changes of the chicken surimi properties were observed during the initial period, i.e. during 3 h of proteins incubation with MTG. Surimi modification with transglutaminase increased the equilibrium water activity in comparison with the value obtained for the control sample. At the same time, the mean diffusion coefficient in the enzymatically modified poultry surimi sample reached the value nearly twice higher than in the control sample.
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Okereke, Victor I., E. Robert Baumann, T. Al Austin, and Donna Schulze Lutz. "Midwest (U.S.A.) reservoir water quality modification." Water, Air, and Soil Pollution 37, no. 3-4 (1988): 325–41. http://dx.doi.org/10.1007/bf00192944.
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Okereke, Victor I., E. Robert Baumann, T. Al Austin, and Donna Schulze Lutz. "Midwest (U.S.A.) reservoir water quality modification." Water, Air, and Soil Pollution 37, no. 3-4 (1988): 343–54. http://dx.doi.org/10.1007/bf00192945.
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Miller, Daniel J., Daniel R. Dreyer, Christopher W. Bielawski, Donald R. Paul, and Benny D. Freeman. "Surface Modification of Water Purification Membranes." Angewandte Chemie International Edition 56, no. 17 (2017): 4662–711. http://dx.doi.org/10.1002/anie.201601509.
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Mitusińska, Karolina, Tomasz Magdziarz, Maria Bzówka, Agnieszka Stańczak, and Artur Gora. "Exploring Solanum tuberosum Epoxide Hydrolase Internal Architecture by Water Molecules Tracking." Biomolecules 8, no. 4 (2018): 143. http://dx.doi.org/10.3390/biom8040143.
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Several different approaches are used to describe the role of protein compartments and residues in catalysis and to identify key residues suitable for the modification of the activity or selectivity of the desired enzyme. In our research, we applied a combination of molecular dynamics simulations and a water tracking approach to describe the water accessible volume of Solanum tuberosum epoxide hydrolase. Using water as a molecular probe, we were able to identify small cavities linked with the active site: (i) one made up of conserved amino acids and indispensable for the proper positioning of catalytic water and (ii) two others in which modification can potentially contribute to enzyme selectivity and activity. Additionally, we identified regions suitable for de novo tunnel design that could also modify the catalytic properties of the enzyme. The identified hot-spots extend the list of the previously targeted residues used for modification of the regioselectivity of the enzyme. Finally, we have provided an example of a simple and elegant process for the detailed description of the network of cavities and tunnels, which can be used in the planning of enzyme modifications and can be easily adapted to the study of any other protein.
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Ferencz, Beata, and Jaroslaw Dawidek. "Water balance of lake-catchment systems with transformed water distribution." Management of Environmental Quality: An International Journal 25, no. 4 (2014): 480–92. http://dx.doi.org/10.1108/meq-05-2013-0062.
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Purpose – The purpose of this paper is to assess the scale of changes in the distribution of water and their influence on the components of the hydrological balance in two lake catchments situated in the Leczna-Wlodawa Lake District. Design/methodology/approach – In order to estimate the scale of man-made modification of water distribution an analysis of published cartographic materials was used. The maps cover time-scale of over 150 years. The analysis was completed by territorial research carried out during water years 2007-2009. The elements of water balance equation were calculated on the basis of daily water levels, discharge, precipitations and lake volumes. Evaporation was calculated as the difference of balance gains and losses (runoff deficit). Findings – The study has shown high permanent human pressure on lake-catchment systems under study, since the 50 of the nineteenth century. Naturally drainless lakes were connected to the system of surface runoff, which modified radically directions and pace of water circulation. The most pronounced hydrologic changes of the lake-catchment systems under study occurred in the 60 of the twentieth century. Human pressure on water conditions resulted in changes of water balance elements relation (increased surface inflow and outflow). Originality/value – In the ecosystems with zonal watersheds, even slight modification of water distribution may lead to radical changes in the structure of lake-catchment systems’ water balance. The paper is first in polish literature that documents major water divide translocation, as well as bifurcation in the drainage area of the highest cascade lake. Man-made modifications cause natural ecosystems degradation, especially in the areas built with peat-bogs.
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Karlsson, Olov, Petteri Torniainen, Ola Dagbro, Kurt Granlund, and Tom Morén. "Presence of water-soluble compounds in thermally modified wood: Carbohydrates and furfurals." BioResources 7, no. 3 (2012): 3679–89. http://dx.doi.org/10.15376/biores.7.3.3679-3689.
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With thermal modification, changes in properties of wood, such as the presence of VOC and water-soluble carbohydrates, may occur. Thermal modifications under saturated steam conditions (160 °C or 170 °C) and superheated steam conditions (170, 185, and 212 °C) were investigated by analysing the presence of water-soluble 5-(hydroxymethyl)furfural (HMF), furfural, and carbohydrates in heat-treated wood. The influence of thermal modifications on Scots pine, Norway spruce, and silver birch was also studied. Furfurals were analysed using HPLC at 280 nm, while monosaccharides and water-soluble carbohydrates were determined by GC-FID as their acetylated alditiols and, after methanolysis, as their trimethylsilylated methyl-glycosides, respectively. The amount of furfurals was larger in boards thermally modified under saturated steam conditions than those treated under superheated steam conditions. Generally, more of HMF than furfural was found in the thermally modified boards. In process water, in which saturated steam conditions had been used, furfural and only traces of HMF were found. Higher content of water-soluble carbohydrates was found in boards treated in saturated steam rather than in superheated steam. After modification in saturated steam, substantial parts of the water-soluble carbohydrates were due to monosaccharides, but only traces of monosaccharides were found in boards treated under superheated steam conditions.
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Brostow, Witold, and Tea Datashvili. "Chemical modification and characterization of boehmite particles." Chemistry & Chemical Technology 2, no. 1 (2008): 27–32. http://dx.doi.org/10.23939/chcht02.01.027.
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Polymerizable organic silane molecules 3-(trimethoxysilyl)propylmethacrylate (3MPS) and vinyltri(2-methoxyethoxy)silane (VTMES) have been introduced onto surfaces of high purity Boehmite (a commercial alumina) via hydroxyl groups on the oxides in order to obtain organic-inorganic hybrid “macromonomers”. Changes of surface characteristics have been determined using thermogravimetric analysis (TGA) and Fourier-transform infrared spectroscopy (FTIR). The influence of the type of silane used and modification conditions have been determined. Preheating was applied to some Boehmite samples; it leads to lower concentrations of –OH groups on the powder surface and the adsorption yields lower than in samples without preheating. Modification leads to surface hydrophobicity and thus reduces significantly water adsorption; in TGA we see desorption of water below 423 K only in un-modified Boehmite.
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Marta, Herlina, Ari Rismawati, Giffary Pramafisi Soeherman, et al. "The Effect of Dual-Modification by Heat-Moisture Treatment and Octenylsuccinylation on Physicochemical and Pasting Properties of Arrowroot Starch." Polymers 15, no. 15 (2023): 3215. http://dx.doi.org/10.3390/polym15153215.
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Starch is widely applied in various industrial sectors, including the food industry. Starch is used as a thickener, stabilizer, or emulsifier. However, arrowroot starch generally has weaknesses, such as unstable under heating and acidic conditions, which are generally applied to processing in the food industry. Modifications were applied to improve the characteristics of native arrowroot starch. In this study, arrowroot starch was modified by heat-moisture treatment (HMT), octenylsuccinylation (OSA), and dual modification between OSA and HMT in a different sequence––namely, HMT followed by OSA, and OSA followed by HMT. This study aims to determine the effect of different modification methods on the physicochemical and functional properties of native arrowroot starch. The result shows that both single HMT and dual modification caused damage to native starch granules, such as the formation of cracks and roughness. For single OSA treatment, especially, there is no significant change in granule morphology after modification. All modification treatments did not change the crystalline type of starch but reduced the RC of native starch. Both single HMT and dual modifications (HMT-OSA, OSA-HMT) increased pasting temperature and setback, but, conversely, decreased the peak and the breakdown viscosity of native starch, whereas single OSA had the opposite trend compared with the other modifications. HMT played a greater role in increasing the thermal stability and the retrogradation ability of arrowroot starch. Both single modifications (HMT and OSA) increased the hardness and gumminess of native starch, and the opposite was true for the dual modifications. HMT had a greater effect on color characteristics, where the lightness and whiteness index of native arrowroot starch decreased. Single OSA modification increased swelling volume higher than dual modification. Both single HMT and dual modifications increased water absorption capacity and decreased the oil absorption capacity of native arrowroot starch.
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Zulfikar and Dean Corio. "Modifikasi Sudu-sudu Blower Sentrifugal yang Diaplikasikan pada Turbin Pico Hydro." Electrician : Jurnal Rekayasa dan Teknologi Elektro 17, no. 1 (2023): 26–30. http://dx.doi.org/10.23960/elc.v17n1.2409.
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The water turbine must be specially designed according to the calculation of its energy potential, proportional to the height of the falling water and the discharge. This research is conducted to study the solution fluid engine that functions as a pico hydro water turbine, namely a centrifugal blower with a simple construction, operating at low head, small discharge, easy installation and operation and low price. The blower used in this test is a blower that is already on the market with an impeller diameter of 15 cm, inlet size of 2 inches. The test was carried out at a constant head (falling water height) of 5 m. The working principle of the blower is reversed, that is, water from a certain height flows through the rapid pipe and enters the exhaust side of the blower until the water moves the blower and exits through the blower inlet to the draftube. The purpose of this study was to determine the effect of modification of the blades on the increase in efficiency of the picohydro turbine. This study uses an analytical method with testing parameters based on calculating the value of water discharge, water power, torque, turbine mechanical power and turbine efficiency. To increase the power and efficiency of the blower as a turbine, modifications are made to the blower blades. With the modification of the blower blades, the turbine efficiency increases by 10% from before the modification.
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Stangierski, J., R. Rezler, H. M. Baranowska, and S. Poliszko. "Effect of enzymatic modification on frozen chicken surimi." Czech Journal of Food Sciences 31, No. 3 (2013): 203–10. http://dx.doi.org/10.17221/181/2012-cjfs.
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The effects were assessed of the addition of microbial origin transglutaminase (MTG) and modification time of proteins in frozen chicken surimi on its texture, rheological attributes, molecular dynamics of water, water activity, and thermal properties of proteins. Surimi was produced from mechanically separated poultry meat. The amount of 3 g/kg MTG were added to samples of fresh, frozen (stored at –22°C for 30 days), and defrosted surimi which were incubated for a max. 9 h at 15°C. The highest values of the analysed texture attributes and rheological modules were recorded in the case of the sample enzymatically modified before freezing. The values of spin-lattice relaxation time were significantly higher in the control system. In comparison to non-modified surimi, the samples treated with MTG were characterised by a considerable increase in the equilibrium water activity. After 7 h modification, the value of enthalpy for surimi protein was by approx. 30% lower in comparison to the control sample.  
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Fadhli, M. K., N. Arpi, and S. Noviasari. "Chemical characteristics of three variations of sweet potato (Ipomoea batatas L.) flour with physical modifications." IOP Conference Series: Earth and Environmental Science 1183, no. 1 (2023): 012053. http://dx.doi.org/10.1088/1755-1315/1183/1/012053.
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Abstract This study aims to determine the chemical characteristics of three variations of sweet potato flour with three physical modifications. Purple, orange, and white sweet potatoes were used, and the modifications of starch were conducted using Heat Moisture Treatment (HMT), Annealing Method (AM), and Preheating Method (PM). The data obtained were analyzed statistically using Analysis of Variance. Based on the research results, physical modification of sweet potato flour variations on the characteristics of physicochemical properties had a very significant (P< 0.05) effect on yield, water content, and starch content. However, the physical modification of sweet potato flour variations on the characteristics of physicochemical properties did not significantly affect (P>0.05) fat and protein content. The results showed that the highest average yield of 21.78% was obtained by using PM. The highest water content of 7.28% was obtained using AM, and the highest fat content of 2.29% was obtained using PM. The highest protein content of 4.47% was obtained by using HMT, and the highest starch content of 71.23% was obtained using AM and PM. The best physical modification method was the PM, with a yield of 21.78%, fat content of 2.29%, and starch content of 71.23%.
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Tan, Dan Jun, Ying Wang, Meng Zhang, Peng Qi Wang, and Liang He. "Modification of Graphite-Gypsum System." Applied Mechanics and Materials 687-691 (November 2014): 4382–85. http://dx.doi.org/10.4028/www.scientific.net/amm.687-691.4382.
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There were many problems when natural flake graphite was used in gypsum as an absorbing agent, such as absorbing large amount of water, a poor interfacial compatibility and so on. In this paper, polycarboxylate-based water reducer and AES (sodium alcohol ether sulphate) are used to modify graphite-gypsum system. The results show that both agents are effective to improve the properties of gypsum system and the former is best. Compared with the sample without any reagents, polycarboxylate-based water reducer can reduce the water-solid ratio from 1.1 to 0.9, increase the compressive strength from 0.106Mpa to 0.701Mpa and the flexural strength form 0.064Mpa to 0.312Mpa.
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Armaković, Sanja J., Stevan Armaković, and Maria M. Savanović. "Photocatalytic Application of Polymers in Removing Pharmaceuticals from Water: A Comprehensive Review." Catalysts 14, no. 7 (2024): 447. http://dx.doi.org/10.3390/catal14070447.
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This comprehensive review covers recent advancements in utilizing various types of polymers and their modifications as photocatalysts for the removal of pharmaceutical contaminants from water. It also considers polymers that enhance the photocatalytic properties of other materials, highlighting their dual role in improving water purification efficiency. Over the past decades, significant progress has been made in understanding the photocatalytic properties of polymers, including organic, inorganic, and composite materials, and their efficacy in degrading pharmaceuticals. Some of the most commonly used polymers, such as polyaniline, poly(p-phenylene vinylene), polyethylene oxide, and polypyrole, and their properties have been reviewed in detail. Physical modification techniques (mechanical blending and extrusion processing) and chemical modification techniques (nanocomposite formation, plasma modification techniques, surface functionalization, and cross-linking) have been discussed as appropriate for modifying polymers in order to increase their photocatalytic activity. This review examines the latest research findings, including the development of novel polymer-based photocatalysts and their application in the removal of pharmaceutical compounds, as well as optimization strategies for enhancing their performance. Additionally, challenges and future directions in this field are discussed to guide further research efforts.
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Ma, Futao, Jingjing Liu, Kaixuan Chen, and Zhenmin Cheng. "Thermal Stability Improvement of Cu-Based Catalyst by Hydrophobic Modification in Methanol Synthesis." Processes 12, no. 9 (2024): 2008. http://dx.doi.org/10.3390/pr12092008.
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Water can cause the growth and oxidation of Cu nanoparticles on the surface of Cu-based catalysts, leading to their deactivation. However, during methanol synthesis process from syngas on Cu-based catalysts, water is inevitably produced as a by-product due to the presence of CO2. Therefore, enhancing the stability of Cu-based catalysts during the reaction, particularly in the presence of water, is crucial. In this study, Cu/ZnO/Al2O3 was first subjected to wet etching and then hydrophobically modified using the sol–gel method with methyltrimethoxysilane (MTMS) and the grafting method with 1H,1H,2H,2H-perfluoroalkyltriethoxysilanes (PFOTES) as modifiers. These modifications aimed to mitigate the impact of water on the catalyst and improve its stability. After modification, the catalysts exhibited excellent hydrophobicity and enhanced catalytic activity in the methanol synthesis process. The surface physical properties, composition, and thermal stability of the catalysts before and after hydrophobic modification were characterized by SEM, FT-IR, BET, XRD and TGA. Additionally, molecular dynamics simulations were employed to compare the diffusion behavior of water molecules on the catalyst surfaces before and after hydrophobic modification. The results indicated that the modified catalyst surface formed a micro/nano structure composed of nanosheets and nanosheet clusters, while the hydrophobic modification did not alter the structure of the catalyst. According to the results of simulations, the hydrophobic layers on the modified catalysts were able to expel water quickly from the surfaces and reduce the relative concentration of water molecules at the active sites, thereby improving the stability of the catalyst. Notably, the thermal stability and hydrophobicity of the PFOTES-modified catalyst were superior to those of the MTMS-modified catalyst, resulting in a more significant enhancement in catalyst stability, which aligned with the experimental results.
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Liu, Leifei, Jingmei Zong, Xueqian Hou, and Xiaoyan Liu. "Effect of the Inorganic Modification Mode on the Mechanical Properties of Rubber Recycled Concrete." Materials 17, no. 10 (2024): 2217. http://dx.doi.org/10.3390/ma17102217.
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The reasonable and effective application of waste tires and discarded concrete in concrete is an important branch of green concrete development. This paper investigates the effects of the inorganic modification mode on the basic mechanical properties of rubber recycled concrete based on indoor tests. Inorganic modification, such as water washing, acid washing, and alkaline washing modification, was mainly used to treat and modify rubber particles. The factors affecting the compressive strength, the splitting tensile strength, the flexural strength, the axial compressive strength, and the modulus of elasticity of modified rubber recycled concrete were analyzed. The study results show that the incorporation of recycled aggregates and rubber reduced the mechanical properties of concrete, with the compressive and splitting tensile strengths showing the greatest reductions of 27.36% and 27.24%, respectively. Three modification methods significantly improved the mechanical properties of rubber recycled concrete. The alkali washing modification method was the most effective, maximally improving the mechanical properties of rubber recycled concrete by 7.53–15.51%. The effects of the three modifications on the mechanical properties of concrete were ranked as follows: alkali washing > acid washing > water washing. This study provides a data basis for the practical application of rubber recycled concrete in engineering and a test basis for the development of green concrete.
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Muyideen, O. Bamidele, Oni SarahO., S. AlHassan Ishaku, and M. Olatunbosun Tobiloba. "Chemical modification of grain starch: Proximate and physiochemical analyses." Chemistry International 7, no. 4 (2021): 230–33. https://doi.org/10.5281/zenodo.6848666.
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In this study, starches were extracted from selected grains such as rice, wheat, beans and corn. Starches from the grains were extracted using cold extraction and modified using acetate and hydrochloric acid. The physical, chemical and nutritive values of the modified and unmodified starches were carried out. The percentage yield of starches from wheat, beans, rice and corn were 30.5, 30.0, 15.0 and 10.5 (%), respectively. The water and oil absorption capacities of the unmodified starches were 63.65 & 18.00 % (wheat), 65.00 & 15.35 % (rice), 67.15 & 19.55 % (corn) and 62.25 & 19.55 % (beans). The acid modified starches had the following water and oil absorption capacities 67.30 & 29.65 % (wheat), 69.65 & 20.90 % (rice), 69.10 & 28.75 % (corn) and 67.15& 19.80 % (beans). Acetate modified starches had the following water & oil absorption capacities 65.70 & 16.35 % (wheat), 68.75& 23.90 % (rice), 65.90 & 34.50 % (corn) and 67.30 & 19.80 % (beans). The high-water absorption capacity of the acid modified rice starch shows that it can withstand higher temperature than unmodified rice starch, which is an advantage for its use in cooking<strong>. </strong>The high oil absorption capacity of the acetate modified corn starches can earn it a place in the cosmetic industries. From this finding, it shows that acid and acetate modified starches would be a better composition of talcum powder.
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Anwar, Sri Haryani, Yeni Chandra Dewi, and Novi Safriani. "Karakterisasi sifat fisiko kimia pati bengkuang (Pachirrhyzus erosus) dan pati ganyong (Canna edulis Kerr) modifikasi [Characteristization on physico-chemical properties of modified canna (Canna edulis Kerr.) and jicama (Pachirrhyzus erosus) starches]." Jurnal Teknologi & Industri Hasil Pertanian 26, no. 1 (2021): 25. http://dx.doi.org/10.23960/jtihp.v26i1.25-36.
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Modification of native starch is needed mainly to increase its solubility in water thus broaden its application in food industries. On the other hand, modification of canna and jicama starches have rarely been applied. Physical and chemical modifications of starches are conducted to modify starch characteristics. The research aimed to investigate the physico-chemical properties of canna and jicama starches that had been modified chemically and physically. Chemical modifications which were conducted included modification via substitution with Octenyl Succinate Anhydride (OSA) and hydrolysis using hydrochloric acid (HCl), while physical modification was conducted via the Heat Moisture Treatment (HMT). The starch physico-chemical characteristics evaluated were degree of acid (DA), swelling power, degree of substitution (DS), moisture, ash, fat, and fiber contents. The analysis results showed that moisture, ash, fat, and fiber contents of native canna and jicama starches were not significantly different from those of modified ones. The result also revealed that the type of starches and modification methods increased the swelling power significantly (P≤0,05). The DS of modified canna dan jicama starches were 0.0246% and 0.0176%, respectively. While the DA of modified canna and jicama starches were 0.14% and 0.18%, respectively. This DA values of modified starches by HCL hydrolysis had meet the Indonesian National Standard (SNI 01-2593-1992) which is maximum of 5% for food application.Keywords: canna starch, jicama starch, HMT modification, modified starch, OSA modification
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Le Guyader, M. "Influence de la modification de la norme relative au dénombrement de la flore aérobie revivifiable sur les résultats d'analyses de l'eau potable." Journal européen d’hydrologie 30, no. 2 (1999): 137–43. http://dx.doi.org/10.1051/water/19993002137.
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García, Andreina, Bárbara Rodríguez, Hugo Giraldo, et al. "Copper-Modified Polymeric Membranes for Water Treatment: A Comprehensive Review." Membranes 11, no. 2 (2021): 93. http://dx.doi.org/10.3390/membranes11020093.
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In the last decades, the incorporation of copper in polymeric membranes for water treatment has received greater attention, as an innovative potential solution against biofouling formation on membranes, as well as, by its ability to improve other relevant membrane properties. Copper has attractive characteristics: excellent antimicrobial activity, high natural abundance, low cost and the existence of multiple cost-effective synthesis routes for obtaining copper-based materials with tunable characteristics, which favor their incorporation into polymeric membranes. This study presents a comprehensive analysis of the progress made in the area regarding modified membranes for water treatment when incorporating copper. The notable use of copper materials (metallic and oxide nanoparticles, salts, composites, metal-polymer complexes, coordination polymers) for modifying microfiltration (MF), ultrafiltration (UF), nanofiltration (NF), forward osmosis (FO) and reverse osmosis (RO) membranes have been identified. Antibacterial and anti-fouling effect, hydrophilicity increase, improvements of the water flux, the rejection of compounds capacity and structural membrane parameters and the reduction of concentration polarization phenomena are some outstanding properties that improved. Moreover, the study acknowledges different membrane modification approaches to incorporate copper, such as, the incorporation during the membrane synthesis process (immobilization in polymer and phase inversion) or its surface modification using physical (coating, layer by layer assembly and electrospinning) and chemical (grafting, one-pot chelating, co-deposition and mussel-inspired PDA) surface modification techniques. Thus, the advantages and limitations of these modifications and their methods with insights towards a possible industrial applicability are presented. Furthermore, when copper was incorporated into membrane matrices, the study identified relevant detrimental consequences with potential to be solved, such as formation of defects, pore block, and nanoparticles agglomeration during their fabrication. Among others, the low modification stability, the uncontrolled copper ion releasing or leaching of incorporated copper material are also identified concerns. Thus, this article offers modification strategies that allow an effective copper incorporation on these polymeric membranes and solve these hinders. The article finishes with some claims about scaling up the implementation process, including long-term performance under real conditions, feasibility of production at large scale, and assessment of environmental impact.
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Zilitinkevich, N. S. "Methods of Calculation of Daily Flooded Areas in the Volga Delta During the Flood Periods Based on the Remote Sensing Data." Issledovanie Zemli iz Kosmosa, no. 3 (November 17, 2024): 78–93. http://dx.doi.org/10.31857/s0205961424030065.
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We developed methods for calculating the daily flooded areas in the Volga delta (VD) for the entire flood period using satellite data. The methodology is based on the construction of dependences of the flooding areas of the hydrographic network and interchannel spaces of VD (Ftotal) on the means of daily water levels in the channels of watercourses (НР). Ftotal for individual flood dates were determined using satellite images. Data on НР were taken at hydrological stations (h/s) on the same dates from the State Water Cadastre. These dependencies were used to calculate the daily flooding areas of DV with high accuracy for flood periods of different water contents (high-water, low-water and medium-water contents). This method was developed in two modifications: 1 – modification for the case of the sufficient number of satellite images to cover all the main changes in the course of each phase of the flood, 2 – modification for the case of the insufficient number of satellite images to cover all the main changes in the course of each phase of the flood. We conducted a comparative analysis of daily Ftotal obtained with high accuracy using modification 1 for floods of different water contents (high-water, low-water, medium-water contents). We revealed how floods of different water contents differ in characteristics including timing of passage, amplitude, area of maximum flooding area, duration of the rise phase, decline phase and flood plateau phase. Such calculations have never been conducted before. The results of calculations by this method allow us to identify the spatial-temporal patterns of the VD flooding under different types of water contents. Our method enables to predict the dynamics of floods and to calculate the water balance of the Volga delta.
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Zare, Richard N. "Making Materials That Hate Water to Love Water: The Transformative Power of Chemistry." Molecular Frontiers Journal 01, no. 01 (2017): 10–15. http://dx.doi.org/10.1142/s2529732517400028.
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A simple nonaqueous reaction scheme for transforming the surface of plastics from hydrophobic to hydrophilic is presented. The chemical modification is achieved by the base-catalyzed trans-esterification of polyethylene terephthalate (PET), which is a commonly used plastic. Its use in blood collection tubes is discussed. The surface modification is permanent, inexpensive, rapid, and does not release contaminants. It also causes no optical or mechanical distortion of the plastic. This work demonstrates the power of chemistry to transform common materials.
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Mu, Yan, Ying Li Fu, and Feng Qing Zhao. "Water-Resistant Modification of Desulphurization Gypsum Block." Applied Mechanics and Materials 182-183 (June 2012): 278–82. http://dx.doi.org/10.4028/www.scientific.net/amm.182-183.278.
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A high performance water resistance agent KD-3 prepared from OPC cement, fly ash, slag and additives was used for the modification of hemi-hydrate desulphurization gypsum. Various factors on gypsum block were investigated. The prepared gypsum block possesses excellent water-resistance, good operating property and high mechanical strength. The optimized results was obtained: calcined gypsum 74.9%, KD-3 25%, retarder 0.1%, curing temperature 60°C and curing time 16h.
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LI, Jin-Qi, and Takeshi SHINODA. "Surface Modification by Friction Coating under Water." Journal of the Society of Materials Science, Japan 49, no. 9Appendix (2000): 193–97. http://dx.doi.org/10.2472/jsms.49.9appendix_193.
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Grzegorzewska, Alicja E. "Pharmacologic Modification of Transperitoneal Movement of Water." Peritoneal Dialysis International: Journal of the International Society for Peritoneal Dialysis 10, no. 4 (1990): 291–94. http://dx.doi.org/10.1177/089686089001000409.
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Investigations concerning the influence of pharmacologic agents on transperitoneal water movement are predominantly undertaken in the hope that their results can help in a restoration of net ultrafiltration (UF) volume toward normal in cases with declining UF during long-term dialysis treatment. Net UF volume represents the difference between net transcapillary UF and lymphatic absorption. The choice of a pharmacological agent for enhancing UF depends on the mechanisms responsible for net UF loss, which include: (a) early dissipation of the transperitoneal osmotic gradient; (b) decrease in the peritoneal surface area; (c) Iymphomonokine overproduction; (d) enhanced lymphatic absorption; (e) high residual volumes left in the peritoneal cavity; or (f) a combination of these factors. Leakage of dialysate to the abdominal wall sometimes occurring in peritoneally dialysed patients (1), according to a definition of net UF volume, cannot be regarded as a true UF loss.
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Kusnierz, Paul C. "Reducing Total Dissolved Gas and Gas Bubble Trauma in a Regulated River." Fishes 9, no. 11 (2024): 427. http://dx.doi.org/10.3390/fishes9110427.
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When water is spilled over dams, atmospheric gases can become entrained, resulting in supersaturated water. Total dissolved gas (TDG) > 110% saturation can cause gas bubble trauma (GBT) in fish. The negative effects of GBT include increased buoyancy, decreased swimming performance, and possible mortality. The lower Clark Fork River (LCFR) in Idaho frequently has TDG > 110% saturation due to the spill at Cabinet Gorge Dam as well as from upstream facilities. Spillway crests on Cabinet Gorge Dam were modified to reduce TDG production and the potential harm from GBT. To evaluate the effectiveness of spillway crest modifications, relationships between river discharge and measured TDG were developed pre- and post-modification and used to calculate the predicted TDG in the LCFR pre- and post-modification under two spill season discharge scenarios. The predicted TDG for the scenarios was used with an established TDG-GBT relationship for the LCFR to estimate the expected GBT incidence. Generally, TDG was lower post-modification, and the discharge at which 110% and 120% saturation were exceeded increased by about 198 m3/s. Modification also reduced the number of days with elevated TDG. The lower TDG post-modification resulted in significant (p < 0.05) reductions in the probability of observing GBT. The modification of Cabinet Gorge Dam spillway crests reduced TDG production over a range of discharges and has resulted in improved conditions for fish downstream of the dam.
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Xu, Keying. "Contact Lens Materials and Their Modification Methods." Highlights in Science, Engineering and Technology 125 (February 18, 2025): 197–202. https://doi.org/10.54097/5yr61b74.
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Contact lenses are one of the most successful materials. They are used by over 125 million people around the world. This review gives an description on history, properties and modifications of contact lens materials. Starting from a piece of glass to current silicone hydrogel lenses, contact lens material development has witnessed a huge step. Properties of typical contact lens materials are introduced, including mechanical properties, equilibrium water content, oxygen permeability, and surface properties. Tensile stress is mentioned as a significant mechanical property, whereas wettability and friction are discussed in surface properties. Corresponding modifications to increase wearing comfort are also discussed in this review, such as copolymerization, cross-linking and surface modification. These methods are applied to materials typically silicone hydrogels to increase water content and oxygen permeability or to optimize the mechanical and surface properties. Nowadays, contact lenses in the market provide users with longer wearing time and more comfortable wearing experiences.
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Saleh, Mohammed, Khalid Al-Ismail, Ghadeer Mehyar, Radwan Ajo, and Youngseung Lee. "Effects of chemically modified acorn starch on its functional characteristics and the sustained release properties of monolithic tablets." Italian Journal of Food Science 37, no. 3 (2025): 108–19. https://doi.org/10.15586/ijfs.v37i3.3001.
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This study investigated the various chemical modifications that affect the functional properties of Acorn starch. Acorn starch was modified using octenyl succinic anhydride, sodium trimetaphosphate (STMP), oxidation, and lactic acid at different concentrations, with their impacts assessed at various temperatures. Octenyl succinic anhydride–treated samples exhibited swelling power ranging from 2.9% at 60°C to 10.4% at 90°C. Modification levels significantly decreased swelling power (P < 0.05), due to structural changes in amylose and amylopectin and stabilization of starch granules from cross-linking. Pasting viscosities increased with modification levels; for example, peak viscosity rose from 1736.0 to 2033.0 cP with octenyl succinic anhydride modification from 3.0 to 9.0%. Lactic acid modification resulted in the highest peak viscosities, whereas STMP cross-linkage showed the lowest. The highest water-holding capacity (WHC) of 139.8% was found with octenyl succinic anhydride at 45°C, while STMP at 0.5% had the lowest WHC. Syneresis varied from 6.80 to 25.30% across freeze–thaw cycles, being lowest with oxidation and highest with STMP. Chemical modifications generally reduced dissolution rates, with lactic acid-modified starch showing the lowest dissolution (58.7%) after 24 h. Results indicated that chemical modifications significantly impact the properties of Acorn starch, emphasizing the need for careful selection based on application.
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Xu, Shuangfeng, Ya-nan Wang, and Bi Shi. "Superhydrophobic Modification of Collagen Fiber." Journal of the American Leather Chemists Association 117, no. 10 (2022): 422–31. http://dx.doi.org/10.34314/jalca.v117i10.6182.
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Tanning is considered to be the crosslinking reaction between collagen fibers and tanning agents, and a majority of tanning reactions result in suppressed water absorption and enhanced hydrophobicity of leather. However, extensive use of tanning agents may bring a burden to the environment. Herein, to facilitate a sustainable leather manufacturing industry, we propose a revolutionary strategy of “tanning” without tanning agents. Based on this strategy, superhydrophobic collagen fibers (FAS-CFs) were fabricated through dehydration, followed by superhydrophobic modification. Dehydration aimed to eliminate the “sticky” effect of water on collagen fiber to obtain a dispersed hierarchical structure. Superhydrophobic modification not only dispersed and stabilized the fiber structures, but also protected the fiber dispersity from water immersion. Compared with chrome-tanned collagen fibers (Cr-CFs) and glutaraldehyde-tanned collagen fibers (G-CFs), FAS-CFs showed higher hydrophobicity, lower water absorption, and superior mechanical properties. Meanwhile, FAS-CFs exhibited a high thermal denaturation temperature of 92.5°C and retained their original shape after being heated to 100°C. Therefore, our proposed strategy is expected to be a potential substitute for conventional tanning and might contribute to cleaner and sustainable leather manufacturing.
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Todica, Mihai, Elena Mihaela Nagy, Carmen Niculaescu, Oana Stan, Nicolae Cioica, and Cornel Viorel Pop. "XRD Investigation of Some Thermal Degraded Starch Based Materials." Journal of Spectroscopy 2016 (2016): 1–6. http://dx.doi.org/10.1155/2016/9605312.
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The thermal degradation of some starch based materials was investigated using XRD method. The samples were obtained by thermal extrusion of mixtures of different proportions of starch, glycerol, and water. Such materials are suitable for the manufacturing of low pollutant packaging. Thermal degradation is one of the simplest ways to destroy such materials and this process is followed by structural modification of the local ordering of samples, water evaporation, crystallization, oxidation, or destruction of the chemical bonds. These modifications need to be studied in order to reduce to the minimum production of pollutant residues by burning process. XRD measurements show modification of the local ordering of the starch molecules depending on the temperature and initial composition of the samples. The molecular ordering perturbation is more pronounced in samples with low content of starch.
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Tarik Ahmed, Sabah, and Hussein Hayder Mohammed Ali. "EXPERIMENTAL INVESTIGATION OF NEW DESIGN OF SOLAR WATER DISTILLATION COUPLED WITH FLAT PLATE SOLAR WATER COLLECTOR." IRAQI JOURNAL FOR MECHANICAL AND MATERIALS ENGINEERING 20, no. 3 (2019): 193–207. http://dx.doi.org/10.32852/iqjfmme.v20i3.512.
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An experimental investigation involves the effect of the turning hollow-cylinder within a solar water distillation on the output of distillate water. This study is to be conducted in order to validate the optimum productivity of purification water by turning hollow-cylinder. The experiments were carried out in Kirkuk city, Iraq, 2018.Experimental results demonstrated that a basin water height is (1 cm) gives the better productivity of (1225 ml/ m2.day) for the conventional solar water distillation, and (2 cm) basin water height for the modification solar water distillation gives the optimum productivity which is (3540 ml/m2.day) which represent an increase of 188% when compared with the productivity of the conventional solar water distillation. 0.5 rpm and 1rpm are the optimum rpm for the hollow cylinder for the modification solar water distillation without and with flat plate solar water collector. The maximum percentage of productivity obtained from the modification solar water distillation which connected to a solar water heater with automatically varying speed according to the solar radiation intensity (Auto turning + Collector) gives more than (310%) enhancement. The estimated cost of one litre distillate water output for modification and conventional solar water distilleries were 136 ID and 175 ID respectively.
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Kalantaryan, Marine, Nikolay Chilingaryan, and Armine Meymaryan. "Modification of Irind Mine Pumice Surface." Key Engineering Materials 906 (January 11, 2022): 25–29. http://dx.doi.org/10.4028/www.scientific.net/kem.906.25.
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In the last decade, a continuous increasing research activity is focused on the surface modification of natural porous materials for the efficient removal of oil contaminants from water. A continuous in-situ oil/water separation technique for oil spill cleanup had been designed using surface modified Irind mine pumice as a sorbent. Irind mine pumice is an aluminosilicate rock, with well-developed porosity, mechanical strength, high buoyancy, chemically inert and eco-friendly, therefore it must exhibit certain water-and oil absorption capacities. The modified pumice absorbs a broad variety of oils and organic solvents with high oil absorption capacity and negligible water take-up at both static and dynamic conditions. Irind mine pumice have been used with grain sizes ranging from 2.5 ... 5.0 mm. Oligomethylhydride siloxane is used as a modifier.