56,646 results match your criteria water molecules

Conserved residue PsaB-Trp673 is essential for high-efficiency electron transfer between the phylloquinones and the iron-sulfur clusters in Photosystem I.

Photosynth Res 2021 May 15. Epub 2021 May 15.

Department of Chemistry, University of Louisiana at Lafayette, Lafayette, LA, 70504, USA.

Despite the high level of symmetry between the PsaA and PsaB polypeptides in Photosystem I, some amino acids pairs are strikingly different, such as PsaA-Gly693 and PsaB-Trp673, which are located near a cluster of 11 water molecules between the A and A quinones and the F iron-sulfur cluster. In this work, we changed PsaB-Trp673 to PsaB-Phe673 in Synechocystis sp. PCC 6803. Read More

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Evolution of the linker in microhydrated hydrogen dinitrate anions: From H to H O.

J Comput Chem 2021 May 14. Epub 2021 May 14.

Department of Chemistry and Centre for Scientific Modeling and Computation, Chinese University of Hong Kong, Hong Kong, China.

Hydrogen dinitrate anion, HNO (NO ), is a proton-bound dimer with a very strong hydrogen bond. By employing ab initio molecular dynamics (AIMD) method, we studied the effects of the proton transfer and the rotation of the nitrates on the vibrational profiles of HNO (NO )(H O) (n = 0-2). The AIMD results indicate that the structure of the n = 0 cluster is very flexible, even though its hydrogen bond is quite strong. Read More

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Replica Exchange Molecular Dynamics of Diphenylalanine Amyloid Peptides in Electric Fields.

J Phys Chem B 2021 May 14. Epub 2021 May 14.

School of Physics, University College Dublin, Belfield, Dublin 4, Ireland.

The self-assembling propensity of amyloid peptides such as diphenylalanine (FF) allows them to form ordered, nanoscale structures, with biocompatible properties important for biomedical applications. Moreover, piezoelectric properties allow FF molecules and their aggregates (e.g. Read More

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Investigation of hierarchically porous zeolitic imidazolate frameworks for highly efficient dye removal.

J Hazard Mater 2021 May 5;417:126011. Epub 2021 May 5.

Lab of Applied Biocatalysis, School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China; South China Institute of Collaborative Innovation, Dongguan 221116, China. Electronic address:

Treatment of textile water containing organic molecules as contaminants still remains a challenge and has become a central issue for environment remediation. Here, a nucleotide incorporated zeolitic imidazolate frameworks (NZIF) featuring hierarchically porous structure served as a potential adsorbent for removal of organic dye molecules. Adsorption isotherms of organic dyes were accurately described by Langmuir adsorption model with correlation coefficients of 0. Read More

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Discerning perturbed assembly of lipids in a model membrane in presence of violacein.

Biochim Biophys Acta Biomembr 2021 May 11:183647. Epub 2021 May 11.

Department of Physics, School of Natural Sciences, Shiv Nadar University, NH 91, Tehsil Dadri, G. B. Nagar, Uttar Pradesh 201314, India. Electronic address:

Violacein is a naturally found pigment that is used by some gram negative bacteria to defend themselves from various gram positive bacteria. As a result, this molecule has caught attention for its potential biomedical applications and has already shown promising outcomes as an antiviral, antibacterial, and anti-tumor agent. Understanding the interaction of this molecule with a cellular membrane is an essential step to extend its use in the pharmaceutical paradigm. Read More

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Facile one step green synthesis of iron nanoparticles using grape leaves extract: textile dye decolorization and wastewater treatment.

Water Sci Technol 2021 May;83(9):2242-2258

Department of Chemistry, School of Science and Technology, Cape Breton University, Sydney, Nova Scotia, Canada E-mail:

The existing knowledge on the reactivity of green iron particles on textile dye and wastewater decolorization is very limited. In this study, the potential of green iron particles synthesized using grape leaves extract on reactive dye (reactive red 195, reactive yellow 145, reactive blue 4 and reactive black 5) decolorization were investigated. 95-98% of decolorization was achieved for all reactive dyes at 1. Read More

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Development of a PointNet for Detecting Morphologies of Self-Assembled Block Oligomers in Atomistic Simulations.

J Phys Chem B 2021 May 14. Epub 2021 May 14.

Department of Chemical Engineering and Materials Science, University of Minnesota, 421 Washington Avenue SE, Minneapolis, Minnesota 55455-0132, United States.

Molecular simulations with atomistic or coarse-grained force fields are a powerful approach for understanding and predicting the self-assembly phase behavior of complex molecules. Amphiphiles, block oligomers, and block polymers can form mesophases with different ordered morphologies describing the spatial distribution of the blocks, but entirely amorphous nature for local packing and chain conformation. Screening block oligomer chemistry and architecture through molecular simulations to find promising candidates for functional materials is aided by effective and straightforward morphology identification techniques. Read More

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Endozoicomonadaceae symbiont in gills of Acesta clam encodes genes for essential nutrients and polysaccharide degradation.

FEMS Microbiol Ecol 2021 May 14. Epub 2021 May 14.

Department of Biology, University of Bergen, Norway.

Gammaproteobacteria from the family Endozoicomonadaceae have emerged as widespread associates of dense marine animal communities. Their abundance in coral reefs involves symbiotic relationships and possibly host nutrition. We explored functions encoded in the genome of an uncultured Endozoicomonadaceae 'Candidatus Acestibacter aggregatus' that lives inside gill cells of large Acesta excavata clams in deep-water coral reefs off mid-Norway. Read More

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Aging of PVDF and PES ultrafiltration membranes by sodium hypochlorite: Effect of solution pH.

J Environ Sci (China) 2021 Jun 5;104:444-455. Epub 2021 Jan 5.

Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China. Electronic address:

Sodium hypochlorite (NaClO) is a commonly applied cleaning agent for ultrafiltration membranes in water and wastewater treatment. Long-term exposure to NaClO might change the properties and performance of polymeric membranes, and ultimately shorten membrane lifespan. Active species in NaClO solution vary with solution pH, and the aging effects can change depending on the membrane material. Read More

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Photochemical decoration of silver nanoparticles on silver vanadate nanorods as an efficient SERS probe for ultrasensitive detection of chloramphenicol residue in real samples.

Chemosphere 2021 Jul 26;275:130115. Epub 2021 Feb 26.

Department of Materials and Mineral Resources Engineering, Institute of Mineral Resources Engineering, National Taipei University of Technology, Taipei, 10608, Taiwan.

Aquaculture and farming industries have been seriously threatened by the illegal use of antibiotics as feed-additives to benefit the animal growth. Although various conventional chemical sensing approaches have been widely explored for the trace-level detection of antibiotics, the effective and accurate monitoring techniques are still highly demanded. Herein, we propose a novel surface-enhanced Raman scattering (SERS) substrate with the heterogeneous integration of silver nanoparticles (Ag NPs) on silver vanadate nanorods (β-AgVO NRs) for the ultrasensitive detection of popular antibiotic, chloramphenicol (CAP). Read More

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Synergistic effect of glutaric acid and ammonia/amine/amide on their hydrates in the clustering: A theoretical study.

Chemosphere 2021 Jul 22;275:130063. Epub 2021 Feb 22.

Institute of Functional Material Chemistry, National & Local United Engineering Lab for Power Battery, Faculty of Chemistry, Northeast Normal University, Changchun, 130024, People's Republic of China. Electronic address:

The formation of molecular clusters makes influence on the atmosphere. The clusters of glutaric acid (GA) and common ammonia (A), amine (methylamine MA, dimethylamine DMA) and representative amide (urea U) along with water molecule were systematically studied theoretically. GA-A-nW (n = 1, 2), GA-MA-nW (n = 1, 2), GA-DMA-1W and GA-U-nW (n = 1-6) are predicted to be feasible thermodynamically with the hydrogen bonds as interaction force. Read More

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Effects of mixing, sheeting, and cooking on the starch, protein, and water structures of durum wheat semolina and chickpea flour pasta.

Food Chem 2021 Apr 30;360:129993. Epub 2021 Apr 30.

Departamento de Ingenieria de Procesos e Hidraulica, Universidad Autonoma Metropolitana-Iztapalapa, Apartado Postal 55-534, Iztapalapa 09340, Mexico.

The influence of the pasta preparation stages on starch, proteins, and water structures of semolina and chickpea pasta was studied. The hydrated starch structures (995/1022 FTIR ratio) increased in semolina and reduced in chickpea pasta. The processing stages in semolina pasta led to a significant increase of β-sheet structures (~50% to ~68%). Read More

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Controlling the fractal dimension in self-assembly of terpyridine modified insulin by Fe and Eu to direct in vivo effects.

Nanoscale 2021 May 1;13(18):8467-8473. Epub 2021 Apr 1.

Center for Biopharmaceuticals and Biobarriers in Drug Delivery and Department of Chemistry, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark.

Metal ion-induced self-assembly (SA) of proteins into higher-order structures can provide new, dynamic nano-assemblies. Here, the synthesis and characterization of a human insulin (HI) analog modified at Lys with the tridentate chelator 2,2':6',2''-terpyridine (Tpy) is described. SA of this new insulin analog (LysTpy-HI) in the presence of the metal ions Fe and Eu at different concentrations was studied in solution by fluorescence luminescence and CD spectroscopy, dynamic light scattering, and small-angle X-ray scattering, while surface assembly was probed by AFM. Read More

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Natural plant products as potential inhibitors of RNA dependent RNA polymerase of Severe Acute Respiratory Syndrome Coronavirus-2.

PLoS One 2021 13;16(5):e0251801. Epub 2021 May 13.

High Performance Computing-Medical and Bioinformatics Applications Group, Centre for Development of Advanced Computing (C-DAC), Pune, India.

Drug repurposing studies targeting inhibition of RNA dependent RNA polymerase (RdRP) of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) have exhibited the potential effect of small molecules. In the present work a detailed interaction study between the phytochemicals from Indian medicinal plants and the RdRP of SARS-CoV-2 has been performed. The top four phytochemicals obtained through molecular docking were, swertiapuniside, cordifolide A, sitoindoside IX, and amarogentin belonging to Swertia chirayita, Tinospora cordifolia and Withania somnifera. Read More

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Modulating MnO Interface with Flexible and Self-Adhering Alkylphosphonic Layers for High-Performance Zn-MnO Batteries.

ACS Appl Mater Interfaces 2021 May 13. Epub 2021 May 13.

Department of Chemistry and Biochemistry, Northern Illinois University, DeKalb, Illinois 60115, United States.

Metal oxides are essential electrode materials for high-energy-density batteries, but it remains highly challenging to modulate their interfacial charge-transfer process and improve their cycling stability. Here, using MnO nanofibers as an example, we describe the application of self-assembled alkylphosphonic modification layers for significantly improved cycling stability and high-rate performance of Zn-MnO batteries. Two modifier organic molecules with the same phosphonic functional group but different alkyl tail lengths were employed and systematically compared, including butylphosphonic acid (BPA) and decylphosphonic acid (DPA). Read More

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Iturin: cyclic lipopeptide with multifunction biological potential.

Crit Rev Food Sci Nutr 2021 May 13:1-13. Epub 2021 May 13.

Green Biotechnologies Research Centre of Excellence, University of Limpopo, Mankweng, South Africa.

Iturin, a metabolite produced by , has a broad-spectrum antibacterial effect, and because they are secreted in the rhizosphere of plants, iturins are often mixed with many organic molecules. In recent years, people have improved their separation and purification methods but still cannot achieve simple and effective procedures, making Iturins an ideal biological control agent for insects and bacteria; commercial value still cannot be realized. With the in-depth studies of Iturins, its anti-cancer, hemolysis and other biological activities have gradually been discovered. Read More

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Quenching Mechanism of Uranyl(VI) by Chloride and Bromide in Aqueous and Non-Aqueous Solutions.

J Phys Chem A 2021 May 13. Epub 2021 May 13.

Institute of Chemistry, University of Potsdam, Karl-Liebknecht-Str. 24-25, D-14476 Potsdam, Germany.

A major hindrance in utilizing uranyl(VI) luminescence as a standard analytical tool, for example, in environmental monitoring or nuclear industries, is quenching by other ions such as halide ions, which are present in many relevant matrices of uranyl(VI) speciation. Here, we demonstrate through a combination of time-resolved laser-induced fluorescence spectroscopy, transient absorption spectroscopy, and quantum chemistry that coordinating solvent molecules play a crucial role in U(VI) halide luminescence quenching. We show that our previously suggested quenching mechanism based on an internal redox reaction of the 1:2-uranyl-halide-complex holds also true for bromide-induced quenching of uranyl(VI). Read More

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[Effect of Dendrobii officinalis superfine powder on overeating greasy-induced metabolic hypertension in rats].

Zhongguo Zhong Yao Za Zhi 2021 Apr;46(7):1658-1666

Zhejiang Chinese Medical University Hangzhou 310053, China.

Dendrobii officinalis, with a definite effect of nourishing Yin and clearing heat, has been a folk habit for drinking after being mixed with water. Because its superfine powder has the advantages of high dissolution and convenient drinking, we observed the effect of D. officinalis superfine powder on metabolic hypertension model rats and its possible mechanism in this experiment, which can be used as a reference for its clinical application for hypertension. Read More

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antimicrobial activity of De Wild and Banks ex C. F. Gaertn on selected foodborne pathogens associated to gastroenteritis.

Heliyon 2021 Apr 19;7(4):e06830. Epub 2021 Apr 19.

Centre for Food and Nutrition Research, Institute of Medical Research and Medicinal Plants Studies, POBOX 13033, Yaoundé Cameroon.

This study aimed at evaluating the antimicrobial potential of aqueous, ethanolic and methanolic extracts of two Cameroonian plants against selected foodborne pathogens. Bioactive compounds were extracted from De Wild seeds and Banks ex. C. Read More

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Water-oriented magnetic anisotropy transition.

Nat Commun 2021 May 12;12(1):2738. Epub 2021 May 12.

Institute for Materials Chemistry and Engineering & Integrated Research Consortium on Chemical Sciences (IRCCS), Kyushu University, Fukuoka, 819-0395, Japan.

Water reorientation is essential in a wide range of chemical and biological processes. However, the effects of such reorientation through rotation around the metal-oxygen bond on the chemical and physical properties of the resulting complex are usually ignored. Most studies focus on the donor property of water as a recognized σ donor-type ligand rather than a participant in the π interaction. Read More

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Hormones Nanofiltration in Carbon Nanotubes and Boron Nitride Nanotubes Using Uniform External Electric Field Through Molecular Dynamics.

J Nanosci Nanotechnol 2021 Nov;21(11):5499-5509

Graduate Program In Chemical Engineering, ITEC, Federal University of Pará, c. pp.479, 66075-900 Belém, PA, Brazil.

Hormones are a dangerous group of molecules that can cause harm to humans. This study based on classical molecular dynamics proposes the nanofiltration of wastewater contaminated by hormones from a computer simulation study, in which the water and the hormone were filtered in two single-walled nanotube compositions. The calculations were carried out by changing the intensities of the electric field that acted as a force exerting pressure on the filtration along the nanotube, in the simulation time of 100 ps. Read More

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November 2021

A new method to prepare microparticles based on an Aqueous Two-Phase system (ATPS), without organic solvents.

J Colloid Interface Sci 2021 Mar 27;599:642-649. Epub 2021 Mar 27.

Micro et Nanomédecines translationnelles, MINT, UNIV Angers, UMR INSERM 1066, UMR CNRS 6021, Angers, France. Electronic address:

Hypothesis: Aqueous Two-Phase Systems (ATPS) are aqueous droplets dispersed in an aqueous phase. This specific behavior arises from interactions between at least two water-soluble entities, such as thermodynamically incompatible polymers. A simple, fast, and "green" process to produce ATPS with an aqueous core would be of high interest to the pharmaceutical field for drug delivery. Read More

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Effects of Side-Chain Spacing and Length on Hydration States of Poly(2-methoxyethyl acrylate) Analogues: A Molecular Dynamics Study.

ACS Biomater Sci Eng 2021 May 12. Epub 2021 May 12.

Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka 819-0395, Japan.

Hydration states of polymers are known to directly influence the adsorption of biomolecules. Particularly, intermediate water (IW) has been found able to prevent protein adsorption. Experimental studies have examined the IW content and nonthrombogenicity of poly(2-methoxyethyl acrylate) analogues with different side-chain spacings and lengths, which are HP ( is the number of backbone carbons in a monomer) and PMCA ( is the number of carbons in-between ester and ether oxygens of the side-chain) series, respectively. Read More

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Measurement of the conformational switching of azobenzenes from the macro- to attomolar scale in self-assembled 2D and 3D nanostructures.

Phys Chem Chem Phys 2021 May 12. Epub 2021 May 12.

Institute of Organic Synthesis and Photoreactivity (ISOF) - (CNR), via Gobetti 101, 40129 Bologna, Italy. and Department of Industrial and Materials Science, Chalmers University of Technology, Hörsalvägen 7, 41296 Gothenburg, Sweden.

It is important, but challenging, to measure the (photo)induced switching of molecules in different chemical environments, from solution through thin layers to solid bulk crystals. We compare the cis-trans conformational switching of commercial azobenzene molecules in different liquid and solid environments: polar solutions, liquid polymers, 2D nanostructures and 3D crystals. We achieve this goal by using complementary techniques: optical absorption spectroscopy, femtosecond transient absorption spectroscopy, Kelvin probe force microscopy and reflectance spectroscopy, supported by density functional theory calculations. Read More

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Characterizing the Interplay between Polymer Solvation and Conformation.

J Phys Chem B 2021 May 12. Epub 2021 May 12.

Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States.

Conformational transitions of flexible molecules, especially those driven by hydrophobic effects, tend to be hindered by desolvation barriers. For such transitions, it is thus important to characterize and understand the interplay between solvation and conformation. Using specialized molecular simulations, here we perform such a characterization for a hydrophobic polymer solvated in water. Read More

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Ionosomes: Observation of Ionic Bilayer Water Clusters.

J Am Chem Soc 2021 May 12. Epub 2021 May 12.

Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel.

Emulsification of immiscible two-phase fluids, i.e., one condensed phase dispersed homogeneously as tiny droplets in an outer continuous medium, plays a key role in medicine, food, chemical separations, cosmetics, fabrication of micro- and nanoparticles and capsules, and dynamic optics. Read More

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Assessment of carbamazepine acute toxicity in the cockle Cerastoderma edule through chemical, physiological and biochemical tools.

Braz J Biol 2021 10;82:e247035. Epub 2021 May 10.

University of Carthage, Laboratory of Biomonitoring of the Environment LR01 ES14, Faculty of Sciences of Bizerte, Zarzouna 7021, Tunisia.

The cockle Cerastoderma edule was exposed to four concentrations (5, 10, 20 and 70 μg L-1) of carbamazepine (CBZ). This anticonvulsant was found to alter the mussel behavior of by reducing its clearance rate (CR). Analysis of CBZ accumulation in tissues of C. Read More

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Extending photocatalysis to the visible and NIR: the molecular strategy.

Nanoscale 2021 May 12. Epub 2021 May 12.

Department of Chemistry "Giacomo Ciamician", Via Selmi 2, 40126, Bologna, Italy.

Photocatalysis exploits light to perform important processes as solar fuel production by water splitting, and CO2 reduction or water and air decontamination. Therefore, photocatalysis contributes to the satisfaction of the increasing needs for clean energy, environmental remediation and, most recently, sanification. Most of the efficient semiconductor nanoparticles (NP), developed as photocatalysts, work in the ultraviolet (UV) spectral region and they are not able to exploit either visible (Vis) or near infrared (NIR) radiation. Read More

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The molecular structure of the surface of water-ethanol mixtures.

Phys Chem Chem Phys 2021 May 11. Epub 2021 May 11.

Ultrafast Spectroscopy, AMOLF, 1098 XG Science Park, Amsterdam, The Netherlands.

Mixtures of water and alcohol exhibit an excess surface concentration of alcohol as a result of the amphiphilic nature of the alcohol molecule, which has important consequences for the physico-chemical properties of water-alcohol mixtures. Here we use a combination of intensity vibrational sum-frequency generation (VSFG) spectroscopy, heterodyne-detected VSFG (HD-VSFG), and core-level photoelectron spectroscopy (PES) to investigate the molecular properties of water-ethanol mixtures at the air-liquid interface. We find that increasing the ethanol concentration up to a molar fraction (MF) of 0. Read More

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Physicomechanical performance and encapsulation efficiency of β-cyclodextrin loaded functional electrospun mats based on aliphatic polyesters and their blends.

J Biomater Sci Polym Ed 2021 May 12:1-14. Epub 2021 May 12.

Department of Materials Science and Engineering, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, 110016, India.

Designing complex-forming biodegradable and biocompatible electrospun mats (EMs) by incorporating β- cyclodextrin (β-CD) into polylactic acid PLA)/poly(ε-caprolactone) (PCL) (70:30 w/w) blend based polyester matrix. The influence of β-CD loading on the morphological, thermal, and microstructural properties was investigated using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR). The studies revealed the presence of characteristic interactions between the polymer matrix and β-CD moieties. Read More

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