Journal articles: 'Chemical reverse approach'

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Perrot, Thomas, Guillaume Salzet, Nadine Amusant, Jacques Beauchene, Philippe Gérardin, Stéphane Dumarçay, Rodnay Sormani, Mélanie Morel‐Rouhier, and Eric Gelhaye. "A reverse chemical ecology approach to explore wood natural durability." Microbial Biotechnology 13, no. 5 (March 25, 2020): 1673–77. http://dx.doi.org/10.1111/1751-7915.13540.

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Becattini, Barbara, and Maurizio Pellecchia. "SAR by ILOEs: An NMR-Based Approach to Reverse Chemical Genetics." Chemistry - A European Journal 12, no. 10 (March 20, 2006): 2658–62. http://dx.doi.org/10.1002/chem.200500636.

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Wang, Zhen, Faryal Chaudhry, Maria Naseem, and Adnan Asghar. "Reverse Zagreb and Reverse Hyper-Zagreb Indices for Crystallographic Structure of Molecules." Journal of Chemistry 2020 (March 13, 2020): 1–12. http://dx.doi.org/10.1155/2020/9805829.

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In the fields of chemical graph theory, topological index is a type of a molecular descriptor that is calculated based on the graph of a chemical compound. Topological indices help us collect information about algebraic graphs and give us mathematical approach to understand the properties of algebraic structures. With the help of topological indices, we can guess the properties of chemical compounds without performing experiments in wet lab. There are more than 148 topological indices in the literature, but none of them completely give all properties of under study compounds. Together, they do it to some extent; hence, there is always room to introduce new indices. In this paper, we present first and second reserve Zagreb indices and first reverse hyper-Zagreb indices, reverse GA index, and reverse atomic bond connectivity index for the crystallographic structure of molecules. We also present first and second reverse Zagreb polynomials and first and second reverse hyper-Zagreb polynomials for the crystallographic structure of molecules.

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Sanmartino, J. A., M. Khayet, M. C. García-Payo, H. El-Bakouri, and A. Riaza. "Treatment of reverse osmosis brine by direct contact membrane distillation: Chemical pretreatment approach." Desalination 420 (October 2017): 79–90. http://dx.doi.org/10.1016/j.desal.2017.06.030.

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Yang, C. Y., F. S. Lee, L. Chan, D. A. Sparrow, J. T. Sparrow, and A. M. Gotto. "Determination of the molecular mass of apolipoprotein B-100 A chemical approach." Biochemical Journal 239, no. 3 (November 1, 1986): 777–80. http://dx.doi.org/10.1042/bj2390777.

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Apolipoprotein B-100 (apo B-100) is the protein ligand in low-density lipoproteins that binds to a specific cell-surface receptor. Its molecular mass has been a subject of controversy. We have determined the molecular mass of the protein by a chemical approach. After complete CNBr cleavage, the C-terminal fragment of apo B-100 was purified by reverse-phase h.p.l.c. Amino acid N- and C-terminal analyses confirm that this peptide represents the C-terminal peptide as deduced from the DNA sequence of a human apo B-100 cDNA clone. A chemically synthesized peptide was used to determine the recovery of the peptide (74.72%). On the basis of these data, the molecular mass of apo B-100 was determined to be 496.82 +/- 24.84 kDa.

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Dorhjie, Desmond Batsa, Roman Yusupov, Vladislav Krutko, and Alexey Cheremisin. "Deviation from Darcy Law in Porous Media Due to Reverse Osmosis: Pore-Scale Approach." Energies 15, no. 18 (September 12, 2022): 6656. http://dx.doi.org/10.3390/en15186656.

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Shale and tight hydrocarbons are vital to global energy dynamics. The fluid flow in sub-micron pores of tight oil reservoirs varies from bulk fluid flow. The Darcy law is widely accepted to model creeping flow in petroleum reservoirs. However, traditional reservoir modeling approaches fail to account for the sub-micron mechanisms that govern fluid flow. The accuracy of tight oil reservoir simulators has been improved by incorporating the influence of sub-micron effects. However, there are still factors that affect sub-micron fluid mobility that need investigation. The influence of a chemical potential gradient on fluid flow in sub-micron pores was modeled by solving Darcy and the transport and diluted species equations. The findings indicate that when a chemical potential gradient acts in the opposite direction of a hydraulic pressure gradient (reverse osmosis), there exists a limiting pressure threshold below which a non-linear flow pattern deviating from the Darcy equation is observed. Furthermore, the simulation based on tight reservoir pore parameters shows that when the effect of a chemical potential gradient is added, the resultant flux is 8–49% less. Hence, including the effect of the chemical potential gradient will improve the accuracy of sub-micron pressure dynamics and flow velocity.

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Chen, Yushu, Magali Duvail, Philippe Guilbaud, and Jean-François Dufrêche. "Stability of reverse micelles in rare-earth separation: a chemical model based on a molecular approach." Physical Chemistry Chemical Physics 19, no. 10 (2017): 7094–100. http://dx.doi.org/10.1039/c6cp07843e.

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Xu, Chong, Fuxiang Yang, Shuanggang Duan, Dongzhen Li, Lei Li, Manqun Wang, and Aiming Zhou. "Discovery of behaviorally active semiochemicals in Aenasius bambawalei using a reverse chemical ecology approach." Pest Management Science 77, no. 6 (March 13, 2021): 2843–53. http://dx.doi.org/10.1002/ps.6319.

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G. Ponomareva, Alla, Yevgen P. Yurenko, Roman O. Zhurakivsky, Tanja van Mourik, and Dmytro M. Hovorun. "Conformational Landscape of the Nucleoside Reverse Transcriptase Inhibitor d4T: a Comprehensive Quantum-Chemical Approach." Current Physical Chemistry 3, no. 1 (January 1, 2013): 83–92. http://dx.doi.org/10.2174/1877946811303010012.

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Choo, Young-Moo, Pingxi Xu, Justin K. Hwang, Fangfang Zeng, Kaiming Tan, Ganga Bhagavathy, Kamlesh R. Chauhan, and Walter S. Leal. "Reverse chemical ecology approach for the identification of an oviposition attractant for Culex quinquefasciatus." Proceedings of the National Academy of Sciences 115, no. 4 (January 8, 2018): 714–19. http://dx.doi.org/10.1073/pnas.1718284115.

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Pheromones and other semiochemicals play a crucial role in today’s integrated pest and vector management strategies. These semiochemicals are typically discovered by bioassay-guided approaches. Here, we applied a reverse chemical ecology approach; that is, we used olfactory proteins to lead us to putative semiochemicals. Specifically, we used 7 of the top 10 odorant receptors (ORs) most expressed in the antennae of the southern house mosquito, Culex quinquefasciatus, and which are yet to be deorphanized. We expressed these receptors in the Xenopus oocyte recording system and challenged them with a panel of 230 odorants, including physiologically and behaviorally active compounds. Six of the ORs were silent either because they are not functional or a key odorant was missing. CquiOR36, which showed the highest transcript levels of all OR genes in female antennae, was also silent to all odorants in the tested panel, but yielded robust responses when it was accidentally challenged with an old sample of nonanal in ethanol. After confirming that fresh samples were inactive and through a careful investigation of all possible “contaminants” in the old nonanal samples, we identified the active ligand as acetaldehyde. That acetaldehyde is activating CquiOR36 was further confirmed by electroantennogram recordings from antennae of fruit flies engineered to carry CquiOR36. Antennae of female mosquitoes also responded to acetaldehyde. Cage oviposition and dual-choice assays demonstrated that acetaldehyde is an oviposition attractant in a wide range of concentrations and thus of potential practical applications.

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Drewes, J. E., J. A. McDonald, T. Trinh, M. V. Storey, and S. J. Khan. "Chemical monitoring strategy for the assessment of advanced water treatment plant performance." Water Science and Technology 63, no. 3 (February 1, 2011): 573–79. http://dx.doi.org/10.2166/wst.2011.260.

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A pilot-scale plant was employed to validate the performance of a proposed full-scale advanced water treatment plant (AWTP) in Sydney, Australia. The primary aim of this study was to develop a chemical monitoring program that can demonstrate proper plant operation resulting in the removal of priority chemical constituents in the product water. The feed water quality to the pilot plant was tertiary-treated effluent from a wastewater treatment plant. The unit processes of the AWTP were comprised of an integrated membrane system (ultrafiltration, reverse osmosis) followed by final chlorination generating a water quality that does not present a source of human or environmental health concern. The chemical monitoring program was undertaken over 6 weeks during pilot plant operation and involved the quantitative analysis of pharmaceuticals and personal care products, steroidal hormones, industrial chemicals, pesticides, N-nitrosamines and halomethanes. The first phase consisted of baseline monitoring of target compounds to quantify influent concentrations in feed waters to the plant. This was followed by a period of validation monitoring utilising indicator chemicals and surrogate measures suitable to assess proper process performance at various stages of the AWTP. This effort was supported by challenge testing experiments to further validate removal of a series of indicator chemicals by reverse osmosis. This pilot-scale study demonstrated a simplified analytical approach that can be employed to assure proper operation of advanced water treatment processes and the absence of trace organic chemicals.

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Drewes, J. E., J. A. McDonald, T. Trinh, M. V. Storey, and S. J. Khan. "Chemical monitoring strategy for the assessment of advanced water treatment plant performance." Water Supply 10, no. 6 (December 1, 2010): 961–68. http://dx.doi.org/10.2166/ws.2010.635.

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A pilot-scale plant was employed to validate the performance of a proposed full-scale advanced water treatment plant (AWTP) in Sydney, Australia. The primary aim of this study was to develop a chemical monitoring program that can demonstrate proper plant operation resulting in the removal of priority chemical constituents in the product water. The feed water quality to the pilot plant was tertiary-treated effluent from a wastewater treatment plant. The unit processes of the AWTP were comprised of an integrated membrane system (ultrafiltration, reverse osmosis) followed by final chlorination generating a water quality that does not present a source of human or environmental health concern. The chemical monitoring program was undertaken over 6 weeks during pilot plant operation and involved the quantitative analysis of pharmaceuticals and personal care products, steroidal hormones, industrial chemicals, pesticides, N-nitrosamines and halomethanes. The first phase consisted of baseline monitoring of target compounds to quantify influent concentrations in feed waters to the plant. This was followed by a period of validation monitoring utilising indicator chemicals and surrogate measures suitable to assess proper process performance at various stages of the AWTP. This effort was supported by challenge testing experiments to further validate removal of a series of indicator chemicals by reverse osmosis. This pilot-scale study demonstrated a simplified analytical approach that can be employed to assure proper operation of advanced water treatment processes and the absence of trace organic chemicals.

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13

Kim, Tae-Wan. "S2-03-04: Reverse chemical genetics approach to identify druggable gene products in Alzheimer's disease." Alzheimer's & Dementia 6 (July 2010): S93—S94. http://dx.doi.org/10.1016/j.jalz.2010.05.288.

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14

Zhang, Xumei, Zhizhao Li, Yan Wang, and Wei Yan. "An Integrated Multicriteria Decision-Making Approach for Collection Modes Selection in Remanufacturing Reverse Logistics." Processes 9, no. 4 (April 4, 2021): 631. http://dx.doi.org/10.3390/pr9040631.

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Reverse logistics (RL) is closely related to remanufacturing and could have a profound impact on the remanufacturing industry. Different from sustainable development which is focused on economy, environment and society, circular economy (CE) puts forward more requirements on the circularity and resource efficiency of manufacturing industry. In order to select the best reverse logistics provider for remanufacturing, a multicriteria decision-making (MCDM) method considering the circular economy is proposed. In this article, a circularity dimension is included in the evaluation criteria. Then, analytic hierarchy process (AHP) is used to calculate the global weights of each criterion, which are used as the parameters in selecting RL providers. Finally, technique for order of preference by similarity to ideal solution (TOPSIS) is applied to rank reverse logistics providers with three different modes. A medium-sized engine manufacturer in China is taken as a case study to validate the applicability and effectiveness of the proposed framework.

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Kalafatovic, Daniela, Goran Mauša, Dina Rešetar Maslov, and Ernest Giralt. "Bottom-Up Design Approach for OBOC Peptide Libraries." Molecules 25, no. 15 (July 22, 2020): 3316. http://dx.doi.org/10.3390/molecules25153316.

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One-bead-one-compound peptide libraries, developed following the top-down experimental approach, have attracted great interest in the identification of potential ligands or active peptides. By exploiting a reverse experimental design approach based on the bottom-up strategy, we aimed to develop simplified, maximally diverse peptide libraries that resulted in the successful characterization of mixture components. We show that libraries of 32 and 48 components can be successfully detected in a single run using chromatography coupled to mass spectrometry (UPLC-MS). The proposed libraries were further theoretically evaluated in terms of their composition and physico-chemical properties. By combining the knowledge obtained on single libraries we can cover larger sequence spaces and provide a controlled exploration of the peptide chemical space both theoretically and experimentally. Designing libraries by using the bottom-up approach opens up the possibility of rationally fine-tuning the library complexity based on the available analytical methods.

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Fujioka, Takahiro, Haruka Takeuchi, Hiroaki Tanaka, and Hitoshi Kodamatani. "A surrogate-based approach for trace organic chemical removal by a high-rejection reverse osmosis membrane." Science of The Total Environment 696 (December 2019): 134002. http://dx.doi.org/10.1016/j.scitotenv.2019.134002.

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17

Norberg, Stefan T., Matthew G. Tucker, and Stephen Hull. "Bond valence sum: a new soft chemical constraint forRMCProfile." Journal of Applied Crystallography 42, no. 2 (February 27, 2009): 179–84. http://dx.doi.org/10.1107/s0021889809004981.

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The implementation of a new soft chemical constraint for the reverse Monte Carlo (RMC) programRMCProfile, based on bond valence sum (BVS) calculations, is described and its advantages for the analysis of `total scattering' diffraction data collected from disordered crystalline systems discussed. The inclusion of the BVS formalism proves particularly valuable in the early stages of the RMC fitting procedure, by avoiding the formation of regions containing chemically unreasonable local configurations which can become frozen in. Furthermore, this approach provides the fitting procedure with additional chemical information to differentiate between cation species that share the same crystallographic sites within the averaged unit cell and possess similar neutron scattering lengths. These issues are illustrated using total neutron scattering data collected at room temperature on the oxide-ion conductor Zr2Y2O7and the nonlinear optical material KTiOPO4.

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Moroni, Giovanni, and Marco Rasella. "Application of Regression Spline to Reverse Modeling." Journal of Computing and Information Science in Engineering 7, no. 1 (October 26, 2006): 95–101. http://dx.doi.org/10.1115/1.2424245.

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When dealing with inspection or reverse modeling, the problem of free-form curves and surfaces reconstruction has to be faced starting from a set of measured points. Because in point sampling the acquisition error is unavoidable, curves and surfaces fitting should be based on a rigorous diagnostic phase. We consider statistical regression analysis in which, treating error as a variable of the problem, we distinguish between the systematic behavior of measured points and noise in the reconstruction of curves and surfaces. The model we introduce for a regression based free-form reconstruction is the so-called regression spline. It is a well known model in the literature, with a consolidated theory and applications in fields such as chemical, econometric, and biomedical. Our purpose is to discuss the application of this powerful and flexible approach in a reverse modeling environment.

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Alharbi, Ahmed. "Molecular docking based design of Inhibitors for viral Non-Nucleosidase as potential anti-retroviral agents." Bioinformation 16, no. 10 (October 31, 2020): 736–41. http://dx.doi.org/10.6026/97320630016736.

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Reverse Transcriptase (RT) inhibitors are highly promising agents for use as an effective anti-retroviral therapy (HAART) which is typically a combination of three or four antiretroviral drugs. We used direct drug design approach to discover new chemical entities for the target protein. The validated template of the protein targeting reverse transcriptase PDB ID 1JKH was extracted for three sites hydrophobic, steric, and electronic parameters explain the interactions at the active site by the inhibitors. We used the Zinc library of compounds to explore the possible leads for HAART through RT inhibition. We report 12 new chemical entities with possible activity against the targeted viral protein. These leads will provide new therapeutic means in antiretroviral therapy.

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Bojanic, Nemanja, Aleksandar Fistes, Tatjana Dosenovic, Aleksandar Takaci, Mirjana Brdar, Kiyoshi Yoneda, and Dusan Rakic. "Control of the size and compositional distributions in a milling process by using a reverse breakage matrix approach." Chemical Industry 75, no. 1 (2021): 1–14. http://dx.doi.org/10.2298/hemind201027004b.

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A method based on the reverse breakage matrix approach is proposed for controlling the effects that milling has on the particle size distribution and composition of the comminuted material. Applicability, possibilities, and limitations of the proposed method are tested on examples related to the process of wheat flour milling. It has been shown that the reverse matrix approach can be successfully used for defining the particle size distribution of the input material leading to the desired, predetermined particle size and compositional distribution in the output material. Moreover, we have illustrated that it is possible to simultaneously control both, input and output particle size distribution, together with the composition of the output material.

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Zha, Ruhua, Tuo Shi, Zongwen Zhang, Dongli Xu, Tongwu Jiang, and Min Zhang. "Quasi-reverse-emulsion-templated approach for a facile and sustainable environmental remediation for cadmium." RSC Advances 7, no. 11 (2017): 6345–57. http://dx.doi.org/10.1039/c6ra26949d.

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Wang, Siyuan, Guang Wang, Xi Yang, Hang Yang, Mengjian Zhu, Sen Zhang, Gang Peng, and Zheng Li. "Synthesis of Monolayer MoSe2 with Controlled Nucleation via Reverse-Flow Chemical Vapor Deposition." Nanomaterials 10, no. 1 (December 31, 2019): 75. http://dx.doi.org/10.3390/nano10010075.

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Two-dimensional (2D) layered semiconductor materials, such as transition metal dichalcogenides (TMDCs), have attracted considerable interests because of their intriguing optical and electronic properties. Controlled growth of TMDC crystals with large grain size and atomically smooth surface is indeed desirable but remains challenging due to excessive nucleation. Here, we have synthesized high-quality monolayer, bilayer MoSe2 triangular crystals, and continuous thin films with controlled nucleation density via reverse-flow chemical vapor deposition (CVD). High crystallinity and good saturated absorption performance of MoSe2 have been systematically investigated and carefully demonstrated. Optimized nucleation and uniform morphology could be achieved via fine-tuning reverse-flow switching time, growth time and temperature, with corresponding growth kinetics proposed. Our work opens up a new approach for controllable synthesis of monolayer TMDC crystals with high yield and reliability, which promote surface/interface engineering of 2D semiconductors towards van der Waals heterostructure device applications.

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Vrouwenvelder, J. S., J. C. Kruithof, and M. C. M. Van Loosdrecht. "Integrated approach for biofouling control." Water Science and Technology 62, no. 11 (December 1, 2010): 2477–90. http://dx.doi.org/10.2166/wst.2010.747.

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Despite extensive research efforts, past and present strategies to control biofouling problems in spiral-wound nanofiltration and reverse osmosis membranes have not been successful under all circumstances. Gaining insight in the biofouling process is a first necessity. Based on recent insights, an overview is given of 12 potential complementary approaches to solve biofouling. Combinations of approaches may be more efficient in biofouling control than a single approach. A single approach must be 100% effective, while in combination each individual approach can be partially effective while the combination is still efficient. An integrated Approach for Biofouling Control (ABC) is proposed, based on three corner stones: (i) equipment design and operation, (ii) biomass growth conditions, and (iii) cleaning agents as a framework to control biofouling. While past and present strategies addressed mainly membranes and microorganisms, i.e. removal or inactivation of biomass, this ABC-approach addresses the total membrane filtration system. It is anticipated that this integral approach will enable a more rational and effective control of biofouling. Although in this stage chemical cleaning and biofouling inhibitor dosage seem unavoidable to control biofouling, it is expected that in future—because of sustainability and costs reasons—membrane systems will be developed without or with minimal need for chemical cleaning and dosing. Three potential scenarios for biofouling control are proposed based on (i) biofouling tolerant spiral wound membrane systems, (ii) capillary membranes, and (iii) phosphate limitation.

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Di Martino, Marcello, Styliani Avraamidou, and Efstratios N. Pistikopoulos. "A Neural Network Based Superstructure Optimization Approach to Reverse Osmosis Desalination Plants." Membranes 12, no. 2 (February 9, 2022): 199. http://dx.doi.org/10.3390/membranes12020199.

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An ever-growing population together with globally depleting water resources pose immense stresses for water supply systems. Desalination technologies can reduce these stresses by generating fresh water from saline water sources. Reverse osmosis (RO), as the industry leading desalination technology, typically involves a complex network of membrane modules that separate unwanted particles from water. The optimal design and operation of these complex RO systems can be computationally expensive. In this work, we present a modeling and optimization strategy for addressing the optimal operation of an industrial-scale RO plant. We employ a feed-forward artificial neural network (ANN) surrogate modeling representation with rectified linear units as activation functions to capture the membrane behavior accurately. Several ANN set-ups and surrogate models are presented and evaluated, based on collected data from the H2Oaks RO desalination plant in South-Central Texas. The developed ANN is then transformed into a mixed-integer linear programming formulation for the purpose of minimizing energy consumption while maximizing water utilization. Trade-offs between the two competing objectives are visualized in a Pareto front, where indirect savings can be uncovered by comparing energy consumption for an array of water recoveries and feed flows.

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Saliu, O. D., M. A. Mamo, P. G. Ndungu, and J. Ramontja. "Micellization of a starch–poly(1,4-butylene succinate) nano-hybrid for enhanced energy storage." RSC Advances 11, no. 19 (2021): 11745–59. http://dx.doi.org/10.1039/d1ra00635e.

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26

Chemmangattuvalappil, Nishanth G., Charles C. Solvason, Susilpa Bommareddy, and Mario R. Eden. "Reverse problem formulation approach to molecular design using property operators based on signature descriptors." Computers & Chemical Engineering 34, no. 12 (December 2010): 2062–71. http://dx.doi.org/10.1016/j.compchemeng.2010.07.009.

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Whitehouse, L. E., A. S. Tomlin, and M. J. Pilling. "Systematic lumping of complex tropospheric chemical mechanisms using a time-scale based approach." Atmospheric Chemistry and Physics Discussions 4, no. 4 (July 8, 2004): 3785–834. http://dx.doi.org/10.5194/acpd-4-3785-2004.

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Abstract. This paper presents a formal method of species lumping that can be applied automatically to intermediate compounds within detailed and complex tropospheric chemical reaction schemes. The method is based on grouping species with reference to their chemical lifetimes and reactivity structures. A method for determining the forward and reverse transformations between individual and lumped compounds is developed. Preliminary application to the Leeds Master Chemical Mechanism (MCMv2.0) has led to the removal of 734 species and 1777 reactions from the scheme, with minimal degradation of accuracy across a wide range of test trajectories relevant to polluted tropospheric conditions. The lumped groups are seen to relate to groups of peroxy acyl nitrates, nitrates, carbonates, oxepins, substituted phenols, oxeacids and peracids with similar lifetimes and reaction rates with OH. In combination with other reduction techniques, such as sensitivity analysis and the application of the quasi-steady state approximation (QSSA), a reduced mechanism has been developed that contains 35% of the number of species and 40% of the number of reactions compared to the full mechanism. This has led to a speed up of a factor of 8 in terms of computer calculation time within box model simulations.

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Wu, Jianzhang, Mohammad Reza Farahani, Xiao Yu, and Wei Gao. "Physical-chemical properties studying of molecular structures via topological index calculating." Open Physics 15, no. 1 (May 5, 2017): 261–69. http://dx.doi.org/10.1515/phys-2017-0029.

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AbstractIt’s revealed from the earlier researches that many physical-chemical properties depend heavily on the structure of corresponding moleculars. This fact provides us an approach to measure the physical-chemical characteristics of substances and materials. In our article, we report the eccentricity related indices of certain important molecular structures from mathematical standpoint. The eccentricity version indices of nanostar dendrimers are determined and the reverse eccentric connectivity index for V-phenylenic nanotorus is discussed. The conclusions we obtained mainly use the trick of distance computation and mathematical derivation, and the results can be applied in physics engineering.

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Suzuki, Yoshiaki, and Takeshi Minami. "Technological Development of a Wastewater Reclamation Process for Recreational Reuse: An Approach to Advanced Wastewater Treatment Featuring Reverse Osmosis Membrane." Water Science and Technology 23, no. 7-9 (April 1, 1991): 1629–38. http://dx.doi.org/10.2166/wst.1991.0617.

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The purpose of this survey is to explore ways of reclaiming wastewater to produce high-quality low-cost water for recreational reuse by using a reverse osmosis membrane in advanced wastewater treatment. We examined membrane modules that were able to be used for wastewater treatment in fiscal year 1988. The parameters used to evaluate the membrane were the permeate quantity, permeate water quality, flux decline coefficient, and recovery rate of the permeate quantity by chemical cleaning. As a result, spiral-wound polyvinyl alcohol composite membrane and hollow-fiber cellulose triacetate reverse osmosis membrane were found to be of high practical value. The permeate through these membranes was colorless, transparent, and odorless, with an appearance equivalent to city water. The rejection rate of the fecal coliform group was 100% and the COD of the permeate was 1-2 mg/l, with a chromaticity of 1 degree or less and a phosphorus content of 0.01 mg/l. Under the same pressure condition, these membranes provided three times more permeate quantity than a conventional acetyl cellulose membrane having a time-proven performance. Moreover, these membranes were sufficiently resistant to fouling that they can recover to a 100% permeate quantity by chemical cleaning when they were fouled.

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Giraud, Martin, Cendrine Gatumel, Stéphane Vaudez, Jeremy Nos, Thierry Gervais, Guillaume Bernard-Granger, and Henri Berthiaux. "Multi-scale homogeneity analysis of co-milled powders: Development of a reverse approach to assess quality of mixtures." Powder Technology 400 (March 2022): 117263. http://dx.doi.org/10.1016/j.powtec.2022.117263.

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Shangin, Pavel G., Irina V. Krylova, Andrey V. Lalov, Anna Y. Kozmenkova, Evgeniya A. Saverina, Petr A. Buikin, Alexander A. Korlyukov, et al. "Supramolecular D⋯A-layered structures based on germanium complexes with 2,3-dihydroxynaphthalene and N,N′-bidentate ligands." RSC Advances 11, no. 35 (2021): 21527–36. http://dx.doi.org/10.1039/d1ra02691g.

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The concept of using redox-active ligands is often considered from ‘their effect on the metal center properties’ point of view. We present the reverse side of this approach – change of redox properties of ligands under the influence of metal.

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Labib, Mahmoud, Patrick O. Shipman, Sanela Martić, and Heinz-Bernhard Kraatz. "A bioorganometallic approach for rapid electrochemical analysis of human immunodeficiency virus type-1 reverse transcriptase in serum." Electrochimica Acta 56, no. 14 (May 2011): 5122–28. http://dx.doi.org/10.1016/j.electacta.2011.03.063.

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Sakin, Ali, and Irfan Karagoz. "Numerical prediction of short-cut flows in gas-solid reverse flow cyclone separators." Chemical Industry and Chemical Engineering Quarterly 23, no. 4 (2017): 483–93. http://dx.doi.org/10.2298/ciceq161009002s.

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The effect of operational and geometrical parameters on the short-cut flow in cyclone separators has been investigated computationally using the Reynolds stress model (RSM). The motion of solid particles in the flow field was simulated using the Eulerian-Lagrangian approach with one way discrete phase method (DPM). Eleven cyclones with different cone tip diameters, vortex finder lengths and diameters were studied and the simulation results were analyzed in terms of velocity fields, pressure drops, cut-off diameters and short-cut flows. The numerical simulation was verified with the published experimental results. The results obtained demonstrate that all three parameters, particularly, vortex finder diameter, have significant effects on the cut-off diameter (collection efficiency), the short-cut flow and the pressure drop.

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VAILIKHIT, V., P. BUNSAWANSONG, S. TECHASAKUL, and S. HANNONGBUA. "CONFORMATIONAL ANALYSIS OF NEVIRAPINE IN SOLUTIONS BASED ON NMR SPECTROSCOPY AND QUANTUM CHEMICAL CALCULATIONS." Journal of Theoretical and Computational Chemistry 05, no. 04 (December 2006): 913–24. http://dx.doi.org/10.1142/s0219633606002702.

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The conformational analysis of HIV-1 Reverse Transcriptase Inhibitor, nevirapine, 11-cyclopropyl-5,-11dihydro-4-methyl-6H-dipyrido[3,2-b2′,3′-e][1,4]diazepin-6-one, was investigated using ab initio and density functional theory calculations. The fully optimized structures and rotational potential energies of the nitrogen and carbon bonds in the cyclopropyl ring (C15-N11-C17-C19, α) were examined in detail. Geometries obtained from all applied calculations show similarities to the complex structure with HIV-1 reverse transcriptase. To obtain more information on the structure, conformational minima of nevirapine, optimized at the B3LYP/6-31G** level, were calculated for the 1H, 13C, and 15N-NMR chemical shifts at the B3LYP/6-311++G** level using the GIAO approach in DMSO and chloroform IEFPCM solvation models. The calculated 1H, 13C-NMR chemical shifts agree well with the experimental data, which indicates that the geometry of nevirapine in solution is similar to that of the molecule in the inhibition complex. Solvation free energies (ΔG sol ) of nevirapine in DMSO and chloroform were also obtained.

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Xu, Wenxuan, and Qingchun Ge. "Synthetic polymer materials for forward osmosis (FO) membranes and FO applications: a review." Reviews in Chemical Engineering 35, no. 2 (February 25, 2019): 191–209. http://dx.doi.org/10.1515/revce-2017-0067.

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Abstract Forward osmosis (FO) has played an important role in alleviating the problems caused by freshwater shortage and water contamination in recent years. However, issues of low water permeability, reverse solute diffusion, concentration polarization and membrane fouling are still widely present in FO processes. These challenges are the current research focus in exploring novel FO membranes. Fabricating FO membranes from chemically modified commercial polymers is a relatively novel approach and has proven effective in obtaining appropriate FO membranes. This paper focuses on the progress of FO membranes made specially from chemically modified polymer materials. First of all, a brief overview of commercial polymers commonly used for FO membrane fabrication is provided. Secondly, the chemical modification strategies and synthesis routes of novel polymer materials as well as the resultant FO membrane performance are presented. The strengths and weaknesses of chemical modifications on polymer materials are assessed. Then, typical FO applications facilitated by the FO membranes made from modified polymer materials are exemplified. Finally, challenges and future directions in exploring novel polymers through chemical modifications for FO membrane fabrication are highlighted. This review may provide new insights into the future advancement of both novel membrane materials and FO membranes.

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Whitehouse, L. E., A. S. Tomlin, and M. J. Pilling. "Systematic reduction of complex tropospheric chemical mechanisms, Part II: Lumping using a time-scale based approach." Atmospheric Chemistry and Physics 4, no. 7 (October 5, 2004): 2057–81. http://dx.doi.org/10.5194/acp-4-2057-2004.

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Abstract. This paper presents a formal method of species lumping that can be applied automatically to intermediate compounds within detailed and complex tropospheric chemical reaction schemes. The method is based on grouping species with reference to their chemical lifetimes and reactivity structures. A method for determining the forward and reverse transformations between individual and lumped compounds is developed. Preliminary application to the Leeds Master Chemical Mechanism (MCMv2.0) has led to the removal of 734 species and 1777 reactions from the scheme, with minimal degradation of accuracy across a wide range of test trajectories relevant to polluted tropospheric conditions. The lumped groups are seen to relate to groups of peroxy acyl nitrates, nitrates, carbonates, oxepins, substituted phenols, oxeacids and peracids with similar lifetimes and reaction rates with OH. In combination with other reduction techniques, such as sensitivity analysis and the application of the quasi-steady state approximation (QSSA), a reduced mechanism has been developed that contains 35% of the number of species and 40% of the number of reactions compared to the full mechanism. This has led to a speed up of a factor of 8 in terms of computer calculation time within box model simulations.

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Armetta, Francesco, Maria Luisa Saladino, Maria Clara Martinelli, Rosario Vilardo, Gianfranco Anastasio, Sebastiano Trusso, Viviana Mollica Nardo, Dario Giuffrida, and Rosina Celeste Ponterio. "Improved chemometric approach for XRF data treatment: application to the reverse glass paintings from the Lipari collection." RSC Advances 13, no. 7 (2023): 4495–503. http://dx.doi.org/10.1039/d2ra08178d.

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Gosiewski, Krzysztof. "Effective approach to cyclic steady state in the catalytic reverse-flow combustion of methane." Chemical Engineering Science 59, no. 19 (October 2004): 4095–101. http://dx.doi.org/10.1016/j.ces.2004.05.035.

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Chávez, Matías, and Matthias Ernst. "A continuous approach to Floquet theory for pulse-sequence optimization in solid-state NMR." Journal of Chemical Physics 157, no. 18 (November 14, 2022): 184103. http://dx.doi.org/10.1063/5.0109229.

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We present a framework that uses a continuous frequency space to describe and design solid-state nuclear magnetic resonance (NMR) experiments. The approach is similar to the well-established Floquet treatment for NMR, but it is not restricted to periodic Hamiltonians and allows the design of experiments in a reverse fashion. The framework is based on perturbation theory on a continuous Fourier space, which leads to effective, i.e., time-independent, Hamiltonians. It allows the back-calculation of the pulse scheme from the desired effective Hamiltonian as a function of spin-system parameters. We show as an example how to back-calculate the rf irradiation in the MIRROR experiment from the desired chemical-shift offset behavior of the sequence.

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Pattanaik, Abhyarthana, and Venugopal Rayasam. "Analysis of reverse cationic iron ore fines flotation using RSM-D-optimal design – An approach towards sustainability." Advanced Powder Technology 29, no. 12 (December 2018): 3404–14. http://dx.doi.org/10.1016/j.apt.2018.09.021.

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Lieberman, Daniel M., Marc-Etienne Corthesy, Alex Cummins, and Edward H. Oldfield. "Reversal of experimental parkinsonism by using selective chemical ablation of the medial globus pallidus." Journal of Neurosurgery 90, no. 5 (May 1999): 928–34. http://dx.doi.org/10.3171/jns.1999.90.5.0928.

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Object. Symptoms from Parkinson's disease improve after surgical ablation of the medial globus pallidus (GPm). Although, in theory, selective chemical ablation of neurons in the GPm could preserve vital structures jeopardized by surgery, the potential of this approach is limited when using traditional techniques of drug delivery. The authors examined the feasibility of convection-enhanced distribution of a neurotoxin by high-flow microinfusion to ablate the neurons of the GPm selectively and reverse experimental Parkinson's disease (akinesia, tremor, and rigidity).Methods. Initially, to test the feasibility of this approach, the GPms of two naive rhesus macaques were infused with kainic acid or ibotenic acid through two cannulas that had been placed using the magnetic resonance imaging—guided stereotactic technique. Two weeks later the animals were killed and their brains were examined histologically to determine the presence of neurons in the GPm and the integrity of the optic tract and the internal capsule. To examine the therapeutic potential of this paradigm, unilateral experimental Parkinson's disease was induced in six macaques by intracarotid infusion of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and their behavior was studied for 12 weeks after chemopallidotomy was performed using kainic acid (three animals) or control infusion (three animals).Conclusions. Chemopallidotomy using kainic acid permanently reversed the stigmata of MPTP-induced parkinsonism. By contrast, the control animals exhibited a transient recovery following intrapallidal infusion and then relapsed back to their baseline state. The use of high-flow microinfusion of selectively active toxins has the potential for treatment of Parkinson's disease and, by expanding the range of approachable targets to include large nuclei, for broad applications in clinical and experimental neuroscience.

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Swetha, Rayapadi G., Soumya Basu, Sudha Ramaiah, and Anand Anbarasu. "Multi-Epitope Vaccine for Monkeypox Using Pan-Genome and Reverse Vaccinology Approaches." Viruses 14, no. 11 (November 12, 2022): 2504. http://dx.doi.org/10.3390/v14112504.

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Outbreaks of monkeypox virus infections have imposed major health concerns worldwide, with high morbidity threats to children and immunocompromised adults. Although repurposed drugs and vaccines are being used to curb the disease, the evolving traits of the virus, exhibiting considerable genetic dynamicity, challenge the limits of a targeted treatment. A pan-genome-based reverse vaccinology approach can provide fast and efficient solutions to resolve persistent inconveniences in experimental vaccine design during an outbreak-exigency. The approach encompassed screening of available monkeypox whole genomes (n = 910) to identify viral targets. From 102 screened viral targets, viral proteins L5L, A28, and L5 were finalized based on their location, solubility, and antigenicity. The potential T-cell and B-cell epitopes were extracted from the proteins using immunoinformatics tools and algorithms. Multiple vaccine constructs were designed by combining the epitopes. Based on immunological properties, chemical stability, and structural quality, a novel multi-epitopic vaccine construct, V4, was finalized. Flexible-docking and coarse-dynamics simulation portrayed that the V4 had high binding affinity towards human HLA-proteins (binding energy < −15.0 kcal/mol) with low conformational fluctuations (<1 Å). Thus, the vaccine construct (V4) may act as an efficient vaccine to induce immunity against monkeypox, which encourages experimental validation and similar approaches against emerging viral infections.

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Husaini, Suriani, and Mazrul Nizam Abu Seman. "Performance of layer-by-layer (LbL) polyelectrolyte forward osmosis membrane for humic acid removal and reverse solute diffusion." Chemical Engineering Research Bulletin 19 (September 10, 2017): 75. http://dx.doi.org/10.3329/cerb.v19i0.33799.

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Recent study claimed that forward osmosis (FO) process could handle the fouling problem due it driven force based on natural osmotic pressure. However, researchers observed that FO membrane had problem with reverse solute diffusion (RSD) of draw solution. Therefore, FO membrane properties must be improved either physically or chemically in order to overcome this problem. Among all, surface modification approach has been acknowledged as a best technique to alter the membrane properties without significantly change the bulk membrane properties. In this study, polyelectrolyte FO membrane has been produced through Layer by Layer (LbL) deposition method by using Poly (diallyl-dimethylammoniumchloride), PDADMAC and Poly (sodium 4-styrene-sulfonate), PSS as an active monomers. Humic acid (HA) as part of Natural Organic Matter constituents was used as the feed solution and NaCl as a draw solution. The chemical structure and morphology of the FO membrane were characterized by FTIR and FESEM, respectively. From this study, the highest water flux and humic acid rejection were achieved at 2.5M of draw solution with value of 2.56 L/m².h and 99%, respectively. In general, the water flux increases as the concentration of draw solutions were increased. However, it was observed that reverse salt diffusion (RSD) become worse at higher concentration of draw solution.Chemical Engineering Research Bulletin 19(2017) 75-79

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USKOKOVIĆ, VUK, and MIHA DROFENIK. "SYNTHESIS OF MATERIALS WITHIN REVERSE MICELLES." Surface Review and Letters 12, no. 02 (April 2005): 239–77. http://dx.doi.org/10.1142/s0218625x05007001.

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Reverse micelles as nanosized aqueous droplets existing at certain compositions of water-in-oil microemulsions are widely used today in the synthesis of many types of nanoparticles. However, without a rich conceptual network that would correlate the properties and compositions of reverse micellar microemulsions to the properties of to-be-obtained particles, the design procedures in these cases usually rely on a trial-and-error approach. As like every other science, what is presently known is merely the tip of the iceberg compared to the uninvestigated vastness still lying below. The aim of this article is to present readers with most of the major achievements from the field of materials synthesis within reverse micelles since the first such synthesis was performed in 1982 until today, to possibly open up new perspectives of viewing the typical problems that nowadays dominate the field, and to hopefully initiate the observation and generation of their actual solutions. We intend to show that by refining the oversimplified representations of the roles that reverse micelles play in the processes of nanoparticles synthesis, steps toward a more complex and realistic view of the concerned relationships can be made. The first two sections of the review are of introductory character, presenting the reader with the basic concepts and ideas that serve as the foundations of the field of reverse micellar synthesis of materials. Applications of reverse micelles, other than as media for materials synthesis, as well as their basic structures and origins, together with experimental methods for evaluating their structural and dynamic properties, basic chemicals used for their preparation and simplified explanations of the preparation of materials within, will be reviewed in these two introductory sections. In Secs. 3 and 4, we shall proceed with reviewing the structural and dynamic properties of reverse micelles, respectively, assuming that knowledge of both static and dynamic parameters of microemulsions and changes induced thereof, are a necessary step prior to putting forth any correlations between the parameters that define the properties of microemulsions and the parameters that define the properties of materials synthesized within. Typical pathways of synthesis will be presented in Sec. 5, whereas basic parameters used to describe correlations between the properties of microemulsion reaction media and materials prepared within, including reagent concentrations, ionic strength, temperature, aging time and some of the normally overlooked influences, will be mentioned in Sec. 6. The whole of Sec. 7 is devoted to reviewing water-to-surfactant molar ratio as the most often used parameter in materials design by performing reverse micellar synthesis routes. The mechanisms of particle formation within precipitation synthesis in reverse micelles is discussed in Sec. 8. Synthesis of composites, with special emphasis on silica composites, is described in Sec. 9. All types of materials, classified according to their chemical compositions, that were, to our knowledge, synthesized by using reverse micelles up-to-date, will be briefly mentioned and pointed to the corresponding references in Sec. 10. In Sec. 11, some of the possible future directions for the synthesis of nanostructured materials within reverse micelles, found in combining reverse micellar syntheses and various other synthesis procedures with the aim of reaching self-organizing nanoparticle systems, will be outlined.

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Clapperton, Anthony, Claude Bazin, Dominic Downey, and Jean-Sébastien Marois. "Production of a Phosphate Concentrate from the Tailings of a Niobium Ore Concentrator." Minerals 10, no. 8 (August 4, 2020): 692. http://dx.doi.org/10.3390/min10080692.

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Apatite is the main source of phosphorous for the making of chemical fertilizers. While apatite is usually recovered from phosphate orebodies as the primary product of a mining exploitation, this paper documents the approach taken to produce a phosphate concentrate as a secondary product from the tailings of a niobium ore concentrator. The conventional desliming/flotation scheme used to process phosphate ores was tested and adapted to process one of the reject streams of a niobium concentrator in order to produce a salable phosphate concentrate. For that particular material, it was found that the reverse flotation of apatite yielded better results than the commonly used direct flotation of apatite. The recommended approach to produce the phosphate concentrate is desliming followed by reverse flotation of apatite and an acid leaching of the apatite concentrate to lower the MgO content below the specification for a phosphate concentrate. The obtained phosphate concentrate assays more than 32% P2O5 at a P2O5 recovery of 41%, which although low is found to be economic for the case of processing plant reject tailings.

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Khoo, Ying Siew, Woei Jye Lau, Shadi W. Hasan, Wan Norhayati Wan Salleh, and Ahmad Fauzi Ismail. "New approach of recycling end-of-life reverse osmosis membranes via sonication for microfiltration process." Journal of Environmental Chemical Engineering 9, no. 6 (December 2021): 106731. http://dx.doi.org/10.1016/j.jece.2021.106731.

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Kaiser, Thomas M., Pieter B. Burger, Christopher J. Butch, Stephen C. Pelly, and Dennis C. Liotta. "A Machine Learning Approach for Predicting HIV Reverse Transcriptase Mutation Susceptibility of Biologically Active Compounds." Journal of Chemical Information and Modeling 58, no. 8 (June 28, 2018): 1544–52. http://dx.doi.org/10.1021/acs.jcim.7b00475.

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Liu, Mengjin, Bruno Bienfait, Oliver Sacher, Johann Gasteiger, Roland J. Siezen, Arjen Nauta, and Jan M. W. Geurts. "Combining Chemoinformatics with Bioinformatics: In Silico Prediction of Bacterial Flavor-Forming Pathways by a Chemical Systems Biology Approach “Reverse Pathway Engineering”." PLoS ONE 9, no. 1 (January 8, 2014): e84769. http://dx.doi.org/10.1371/journal.pone.0084769.

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Siddiqi, Areeb, and Carmelo Herdes. "Water effect in the reverse micellar formation of docusate sodium. A coarse-grained molecular dynamics approach." Fluid Phase Equilibria 559 (August 2022): 113469. http://dx.doi.org/10.1016/j.fluid.2022.113469.

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Grange, Andre, Jamal Kassir, and Paul Adams. "Determination of Elemental Sulfur in Phosphorus Pentasulfide. 1. A New Approach Using Reverse-Phase UHPLC and HPLC." Industrial & Engineering Chemistry Research 53, no. 11 (March 4, 2014): 4429–33. http://dx.doi.org/10.1021/ie4034279.

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Journal articles on the topic 'Chemical reverse approach'

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