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The Role of the Chelating Agent on the Structure and Anticorrosion Performances of an Organosilane—Zirconium Sol-Gel Coatings

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Advances in materials Physics and Chemistry 2018年第2期8卷 89-104页

作者： m. O’Sullivan N. A. Odewunmi m. Cullen A. A. Sorour B. Duffy Z. m. Gasem m. Oubaha Dublin Institute of Technology Centre for Research in Engineering Surface Technology Dublin Ireland Centre of Research Excellence in Corrosion King Fahd University of Petroleum and Minerals (KFUPM) Dhahran KSA Department of mechanical Engineering King Fahd University of Petroleum & Minerals (KFUPM) Dhahran KSA

This work investigates the role of the structure of a zirconium complex (ZC) on the condensation and anticorrosion properties of an organosilane sol-gel coating. The structure and reactivity of the ZC were modified by varying the content of methacrylic acid employed as a chelating agent. The structures of the developed materials were characterised by Dynamic Light Scattering, Fourier Transform Infrared Spectroscopy, Differential Scanning Calorimetry and Scanning Electron microscopy. The passive anticorrosion properties were evaluated by Electrochemical Impedance Spectroscopy of the sol-gel coatings deposited on AA2024-T3 substrates. It was highlighted, that a competition in the condensation process of the silicate (Si-O-Si) and silicon-ZC oxides (Si-O-Zr) species can be tailored by the structure of the ZC, with the least chelated ZC exhibiting the highest content of Si-O-Zr bonds. At the same time, it was also found that the coatings containing the highest content of Si-O-Zr groups exhibited the best anticorrosion barrier performances amongst all sol-gel coatings investigated here, therefore presenting the highest condensation degree. This suggested that Si-O-Zr bonds were the essential chemical species responsible for the formation of condensed coatings. A direct correlation between the structure of the coatings and their anticorrosion performances is proposed.

关键词： Organosilane Sol-Gel Coatings Corrosion Structure Condensation

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表皮囊肿令皮肤非典型脂肪瘤/典型的脂肪肉瘤诊断不清:披着羊皮的狼?

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世界核心医学期刊文摘（皮肤病学分册） 2006年第11期2卷 35-35页

作者： mathew R. morgan m.B. 李晓莉 University of South Florida College of Medicine 16124 Chastain Road Odessa FL 33556 United StatesDr.

Epidermal inclusion cysts are an exceedingly common entity seldom seen in association with a malignant tumor. Herein, we report a unique case of an epithelial inclusion cyst seen in association with an atypical lipomatous tumor/well-differentiated liposarcoma. The epidermal inclusion cyst was delimited to the dermis and circumferentially enveloped by an atypical adipocyte tumor containing myxoid foci and comprised of lipoblasts. This case underscores the importance of scrutinizing the entirety of cysts and other ostensibly trivial dermal entities to avoid the pitfall of misdiagnosing a potentially serious tumor.

关键词：脂肪肉瘤表皮囊肿喹碘方脂细胞实性肿物作用点

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积极的师生互动有助于增强学生对学校的归属感

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中国德育 2017年第7期12卷 6-6页

作者： Kenneth m.Tyler Ruby Stevens-morgan Lynda Brown-Wright

初中阶段是青少年开始清晰地认识自我并与他人建立联系的关键时期，这个时期的学生开始对学校产生归属感，而师生问的互动是促进学生产生归属感的关键因素，同时也影响着学生的各种适应性行为，例如学业表现。美国一项调查以776存仞中... 详细信息

初中阶段是青少年开始清晰地认识自我并与他人建立联系的关键时期，这个时期的学生开始对学校产生归属感，而师生问的互动是促进学生产生归属感的关键因素，同时也影响着学生的各种适应性行为，例如学业表现。美国一项调查以776存仞中阶段学生为样本．研究师生间的互动和家校间的差异在学生对学校的归属感中的影响，其中，家校间的差异主要指学饺文化和家庭文化在教育方式、价值观等方面所表现出的差异。研究表明，师生之间愉悦和正而的互动体验有助于学生对学校产生更强的归属感，

关键词：师生互动归属感学生学校家庭文化适应性行为认识自我初中阶段

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maintained Exposure to Spring Water but Not Double Distilled Water in Darkness and Thixotropic Conditions to Weak (~1 µT) Temporally Patterned magnetic Fields Shift Photon Spectroscopic Wavelengths: Effects of Different Shielding materials

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Journal of Biophysical Chemistry 2015年第1期6卷 14-28页

作者： N. J. murugan L. m. Karbowski R. m. Lafrenie m. A. Persinger Department of Biology Laurentian University Sudbury Canada Biomolecular Sciences Program Laurentian University Sudbury Canada

Spring water but not double-distilled water was exposed, in darkness, to a temporally patterned weak magnetic field that has been shown to affect planarian behavior and slow the rate of cancer cell proliferation. Exposure to the magnetic field caused a reliable shift in the peak (longer) wave-length of ~10 nm for fluorescence emissions and a ~20% increase (~100 counts) in fluorescence intensity. Spectral analyses verified a shift of 5 and 10 nm, equivalent to ~1.5 × 10-20 J “periodicity” across the measured wavelengths, which could reflect a change in the an intrinsic energy as predicted by Del Giudice and Preparata and could correspond to two lengths of O-H bonds. Wrapping the water sample containers during exposure with copper foil, aluminum foil, or plastic altered these fluorescent profiles. The most conspicuous effect was the elimination of a ~280 nm peak in the UV-VIS emission spectra only for samples wrapped with copper foil but not aluminum or plastic. These results suggest that weak magnetic fields produce alterations in the water-ionic complexes sufficient to be reliably measured by spectrophotometry. Because the effect was most pronounced when the spring water was exposed in darkness and was not disturbed the role of thixotropic phenomena and Del Giudice entrapment of magnetic fields within coherent domains of Pollack virtual exclusion zones (EZ) may have set the conditions for subsequent release of the energy as photons.

关键词： Water Weak magnetic Fields Photon Emissions Darkness Thixotropic Phenomena Copper Shielding Wavelength Shift 10-20 Joules

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EFFECTS OF DIFFERENT FUNCTIONAL GROUP-CONTAINING ORGANICS ON mORPHOLOGY-CONTROLLED SYNTHESIS OF SILVER NANOPARTICLES AT ROOm TEmPERATURE

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Acta metallurgica Sinica(English Letters) 2006年第5期19卷 362-370页

作者： A.L. Wang H.B. Yin m. Ren X.N. Cheng Q.F. Zhou X.F. Zhang Faculty of Chemistry and Chemical Engineering Jiangsu University Zhenjiang 212013 China Department of Chemical Engineering Jiangsu Teachers University of Technology Changzhou 213001China

Silver nanoparticles with average particles sizes ranging from 2 to 131nm were manipulatively synthesized starting from silver nitrate using different functional group-containing organic modifiers at room temperature. The effects of the organic modifiers on the morphology of the resulting silver nanoparticles were strongly dependent on the intrinsic properties of the functional groups and the reducibility of the reductant. Numerous ether bonds （-0-）present in polyethylene glycol and Tween-80 were beneficial to the formation of silver nanoparticles with particle sizes of several nanometers in a narrow size distribution in both weak and strong reducing environments. Cetyltrimethylammonium bromide induced the formation of nanosized silver triangle plates in a weak reducing environment. The crystal growth of the silver nanoparticles with particle sizes of more than lOnm was postulated through an adhesion process of small-sized particles followed by a subsequent coalescence process under the present reaction conditions.

关键词： silver nanoparticle nanostructure crystal growth TEm (transmissionelectron microscopy)

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Individual stages of bacterial dichloromethane degradation mapped by carbon and chlorine stable isotope analysis

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Journal of Environmental Sciences 2019年第4期31卷 147-160页

作者： maria L.Torgonskaya Anatoly m.Zyakun Yuri A.Trotsenko Kestutis S.Laurinavichius Steffen Kümmel Stéphane Vuilleumier Hans H.Richnow Laboratory of Radioactive Isotopes G.K.Skryabin Institute of Biochemistry and Physiology of MicroorganismsFRC Pushchino Center for Biological ResearchRussian Academy of Sciences Laboratory of mass Spectrometry G.K.Skryabin Institute of Biochemistry and Physiology of MicroorganismsFRC Pushchino Center for Biological ResearchRussian Academy of Sciences Department of Isotope Biogeochemistry Helmholtz Centre for Environmental Research-UFZ Université de Strasbourg CNRS

The fractionation of carbon and chlorine stable isotopes of dichloromethane(CH_2Cl_2,DCm)upon dechlorination by cells of the aerobic methylotroph methylobacterium extorquens Dm4 and by purified DCm dehalogenases of the glutathione S-transferase family was *** effects for individual steps of the multi-stage DCm degradation process,including transfer across the cell wall from the aqueous medium to the cell cytoplasm,dehalogenase binding,and catalytic reaction,were *** observed carbon and chlorine isotope fractionation accompanying DCm consumption by cell supensions and enzymes was mainly determined by the breaking of C\Cl bonds,and not by inflow of DCm into *** isotope effects of DCm dehalogenation were initially masked in high density cultures,presumably due to inverse isotope effects of non-specific DCm oxidation under conditions of oxygen *** cofactor supply remarkably affected the correlation of variations of DCm carbon and chlorine stable isotopes(Δδ^(13)C/Δδ^(37)Cl),increasing corresponding ratio from 7.2–8.6 to 9.6–10.5 under conditions of glutathione *** suggests that enzymatic reaction of DCm with glutathione thiolate may involve stepwise breaking and making of bonds with the carbon atom of DCm,unlike the uncatalyzed reaction,which is a one-stage process,as shown by quantum-chemical modeling.

关键词： Dichloromethane(DCm) microbial degradation Aerobic methylotrophic bacteria Dichloromethane dehalogenase Carbon and chlorine isotopic fractionation

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Comparison of methods for Extraction of Keratin from Waste Wool

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Agricultural Sciences 2016年第10期7卷 670-679页

作者： Eleanor m. Brown Kalgi Pandya maryann m. Taylor Cheng-Kung Liu Biobased and Other Animal Co-Products Research Unit Eastern Regional Research Center Agricultural Research Service US Department of Agriculture Wyndmoor PA USA

The U.S. sheep industry, more than 80,000 producers of 40 million pounds of raw wool per year, is an important component of the meat industry. New methods for the treatment of domestic wool with keratin isolated from the unmarketable fraction of wool, and functionalized for water, oil, or insect repellency are needed. As a first step in the process, we are evaluating the effectiveness of keratin solubilization via relatively benign methods that use thioglycolic acid, bisulfite or sulfide to reduce disulfide bonds, peracetic acid or percarbonate to oxidize disulfides, and urea/thiourea as hydrogen bond disrupters. The procedures are compared in terms of quality of soluble protein, cost effectiveness, potential for upscaling, environmental and operator safety. Successful completion of this project will provide the basis for commercial development of such methods, followed by functional modification of the soluble keratin, and its application to textiles.

关键词： Waste Wool Keratin Extraction Economic Comparison

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Estimation of Reproduction Numbers for the Period of the COVID-19 Epidemic Outbreak in the Central African Republic

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Applied mathematics 2021年第6期12卷 477-488页

作者： Brice m. Yambiyo A. manirakiza Gaston m. N’Guérékata NEERLab Department of Mathematics and Computer Science Université de Bangui Bangui Central African Republic Institut Pasteur Bangui Epidemiological Service Rue Louis Pasteur (RCA) Bangui Central African Republic NEERLab Morgan State University Baltimore MD USA

In this paper, we propose a susceptible-exposed-infection-asymptomatic-hospitalized-recovered (SEIAHR) model with parameters on retrospective social distancing and masking. We estimated the model parameters from information published on the World Health Organization (WHO) website. We found that the actual reproduction number m>Rtm> varies over the period from 03 march to 07 June 2020 and moreover, effective control over contacts and the frequency of population movement would reduce the evolution of the epidemic (control m>cm> ≥ 50%). And the contact check has an influence on the base reproduction number m>Rm>0.

关键词： modeling mathematical Epidemiology Data Analysis

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Statistical modeling of the Influence of Electron Degeneracy on the Interatomic Interactions

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Journal of modern Physics 2010年第3期1卷 171-174页

作者： Anatoly m. Dolgonosov 不详

It is shown that electrons forming simple and multiple covalent bonds may have different contribu-tions to the interatomic interactions due to the degeneracy of electron states. A simple relationship between the lengt... 详细信息

关键词： Interatomic Interactions Covalent Bond Degeneracy of Electron States Theory of Generalized Charges Bond Length Ratio

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Experimental and Computational Analysis of the Solution and Solid-State Conformations of Hexadepsipeptides from Beauveria felina

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Chinese Journal of Chemistry 2022年第3期40卷 378-384页

作者： Feng-Yu Du Attila mandi Xiao-ming Li Ling-Hong meng Tibor Kurtan Bin-Gui Wang CAS&Shandong Province Key Laboratory of Experimental marine Biology Institute of OceanologyChinese Academy of Sciencesand Laboratory of Marine Biology and BiotechnologyQingdao National Laboratory for Marine Science and TechnologyNonhoi Rood 7QingdaoShandong 266071China College of Chemistry and Pharmacy Qingdao Agricultural UniversityQingdooShandong 266109China Department of Organic Chemistry University of DebrecenPOB 4004002 DebrecenHungary College of marine Science University of Chinese Academy of SciencesYuquon Rood 19ABeijing 100049China Center for Ocean mego-Science Chinese Academy of SciencesNonhoi Road 7t QingdaoShandong 266071China

Chemical investigation of Beouverio felina,a marine-derived entomopathogenic fungus,obtained two new destruxin hexadepsipeptides(1 and 2)containing an/.-Ala^(5)residue instead of the usual A/-me-L-Ala^(5).Interestingly,the presence of the/.-Ala^(5)residue enabled two slowly-exchanging solution conformers with cis/trons(ILE^(3))-(A/-me-Val^(4))amide bond for 1 and 2 with 1.5:1 and 1:1 cis/trans ratios,respectively,while only the conformer with c/s amide bond was found in the *** solution and solid-state conformers were studied by NmR,X-ray diffraction and solution and solid-state ECD measurements,as well as by TDDFT-ECD ***(conformational)parameter-activity correlations suggested that the extended destruxin geometry with the preferred c/s(ILE^(3))-(A/-me-Val^(4))bond probably resulted in improved bioactivity and reduced toxicity for the destruxin *** was the first report on the interconversion phenomenon of cis/trans amide bonds of destruxin class,which could give insights in the development of bioactive destruxin agents with lower toxicity.

关键词： Beouveria felina Natural products Destruxin hexadepsipeptides Structure elucidation Conformation analysis

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