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Corrosion protection of AZ31 magnesium alloy treated with La^(3+) modified 3-methacryloxypropyltrimethoxysilane conversion film

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Journal of Rare Earths 2015年第6期33卷 647-654页

作者：乔英杰李文鹏王桂香张晓红 Key Laboratory of Superlight Materials and Surface Technology Ministry of Education College of Materials Science and Chemical Engineering Harbin Engineering University

This study demonstrated the influence of addition concentration of La3＋ on the anti-corrosion behavior of a 3-methacry- loxypropyltrimethoxysilane （MPS） film formed on AZ31 magnesium alloy. The morphology and surface chemistry of the samples were evaluated through scanning electron microscopy （SEM） and Fourier transform infrared spectroscopy （FT-IR）, respectively. The corrosion resistance of the pre-treated AZ31 magnesium alloy was studied during immersion in 0.1 mol/L NaC1 solution, using poten- tiodynamic polarization curves and electrochemical impedance spectra （EIS）. In comparison to MPS film, the low concentration of La3＋ ion modified silane layer exhibited a better anti-corrosion performance, nevertheless, the high concentration of La3＋ ion modified was worse. Results showed that the preferable addition concentration of La3＋ ion in the silane film was 5Х 10-4 mol/L in this experi- ment.

关键词： AZ31 Mg alloy silanes lanthanum corrosion rare earths

Electric Field Driven Surface Ion Transport in Hydrophobic Nanopores

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Chinese Journal of Chemistry 2021年第6期39卷 1511-1516页

作者： Xin-Lei Ding Zeng-Qiang Wu Zhong-Qiu Li Xing-Hua Xia State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjingJiangsu 210023China

Water behavior in nanoconfined hydrophobic environment is different from that in the bulk,which greatly influences mass *** switching of nanopores showing great potential for controlled water or ion transport has been realized through several methods,especially the voltage-triggered wetting/dewetting inspired by biological ion ***,in the hydrophobic silanized nanopores,the finite ionic current is still observed and the ion transport mechanism is not yet ***,we explore the ion transport behavior in the hydrophobic silanized anodic aluminum oxide(AAO).Ion transport through this hydrophobic membrane is confirmed,although no aqueous pathway was *** show that ions transport through the cross-linked silane layer on the inner *** is revealed that metal ions,not just the protons or hydroxide ions,are involved in the ion transport driven by external electric *** study provides a new insight into the ion transport in nanoconfined hydrophobic environment which is helpful to understand the biological processes and design new nanofluidic devices.

关键词： Hydrophobic interface Surface ion transport Nanotechnology Surface chemistry silanes

Recent advances in heterogeneous hydrosilylation of unsaturated carbon-carbon bonds

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Chinese Chemical Letters 2024年第6期35卷 71-85页

作者： Heng Yang Zhijie Zhou Conghui Tang Feng Chen School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationHubei Key Laboratory of Material Chemistry and Service FailureSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The hydrosilylation of unsaturated carbon-carbon bonds is one of the most critical reactions in silicone industrial *** homogeneous Speier's catalyst,Karstedt's catalyst,and other noble metal-based catalysts are widely ***,simplifying the separation of the homogeneous catalyst from reaction products and reducing the high cost of precious metals is still *** review describes the recent development of heterogeneous catalysts for alkene,alkyne,and allene hydrosilylations,which can effectively solve problems in homogeneous hydrosilylation.

关键词： Hydrosilylation Heterogeneous catalysis Alkenes Alkynes silanes

Determination of the Geometric Structure of Core Excited Silane Based on Photoabsorption Spectra Near the Si 2p Edges

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Chinese Physics Letters 2002年第8期19卷 1085-1087页

作者：许如清李家明等 DepartmentofPhysics CenterforAtomicandMolecularNanosciencesTsinghuaUniversityBeijing100084

The photoabsorption spectra near the Si 2p edges of SiH4 have been studied based on the multiple-scattering self-consistent-field method. Our theoretical calculations provide clear assignments of the inner-shell photoabsorption spectra. In comparison with high-resolution experimental spectra, the geometric structure of the Si 2p excited SiH4 * * is recommended as C2v symmetry

关键词： photoabsorption Spectra Caste determination silanes MULTIPLE SCATTERING Sex Determination Processes core NATIONAL EMERGENCY ALARM REPEATER geometrical construction

Luminescent-wavelength tailoring silicon-rich silicon nitride LED

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Chinese Optics Letters 2009年第4期7卷 277-279页

作者：林政道劉致爲林恭如 Graduate Institute of Photonics and Optoelectronics Department of Electrical EngineeringNational Taiwan University

Wavelength tunable photoluminescence （PL） of Si-rich silicon nitride （SRSN） film with buried Si nanocrystals （Si-ncs） grown by plasma enhanced chemical vapor deposition （PECVD） under Sill4 and NH3 environment is investigated. Intense broadband visible emissions tunable from blue to red can be obtained from the as-deposited SiNs thin films with increasing NH3 flow rate from 150 to 250 sccm and detuning the SiH4/NH3 flow ratio during deposition. To date, the normalized PL wavelength of SiNx films after anneal- ing could be detuned over the range of 385-675 nm by decreasing the NH3 flow rate, corresponding to an enlargement on Si-nc size from 1.5-2 to 4-5 nm. The PL linewidth is decreased with increasing ammonia flow rate due to the improved uniformity of Si-ncs under high NH3 flow rate condition. In addition, the PL intensity is monotonically increasing with the blue shift of PL wavelength due to the increasing density of small-size Si-ncs. The ITO/SiNx/p-Si/Al diode reveals highly resistive property with the turn-on voltage and power-voltage slope of only 20 V and 0.18 nW/V, respectively. The turn-on voltage can further reduce from 20 to 3.8 V by improving the carrier injection efficiency with p-type Si nano-rods.

关键词： Flow rate Light emitting diodes Nanocrystals Plasma deposition silanes Silicon Silicon nitride

Isobaric vapor-liquid equilibrium for methyldichlorosilane- dimethyldichlorosilane-benzene system

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2005年第10期6卷 1033-1037页

作者：邱祖民谢心亮余淑娴陈文有谢凤霞刘娟 School of Environmental Science and Engineering Nanchang University School of Environmental Science and Engineering Nanchang University Nanchang 330029 China Editorial Department of Journal of Nanchang University Nanchang 330029 China

The elucidation of vapor-liquid equilibrium (VLE) of the halogenated silane was necessary for the production of silicon derivatives, especially for methylvinyldichlorosilane, due to the lack of the relevant reports. Isobaric VLE for the system methyldichlorosilane-dimethyldichlorosilane-benzene and isobaric VLE of the three binary systems were measured with a new pump-ebulliometer at the pressure of 101.325 kPa. These binary compositions of the equilibrium vapor were calculated according to the Q function of molar excess Gibbs energy by the indirect method and the resulted VLE data agreed well with the thermo-dynamic consistency. Moreover, the experimental data were correlated with the Wilson, NRTL, Margules and van Laar equations by means of the least-squares fit, the acquired optimal interaction parameters were fitted to experimental vapor-liquid equilibrium data for binary systems. The binary parameters of Wilson equation were also used to calculate the bubble point temperature and the vapor phase composition for the ternary mixtures without any additional adjustment. The predicted vapor-liquid equilibrium for the ternary system was in a good agreement with the experimental results. The VLE of binary and multilateral systems provided essential theory for the production of the halogenated silane.

关键词： Benzene Bubbles (in fluids) Derivatives Gibbs free energy Phase composition Phase diagrams silanes Ternary systems Thermodynamics

Silane Terminated Prepolymers: An Alternative to Silicones and Polyurethanes

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Open Journal of Polymer Chemistry 2021年第3期11卷 31-54页

作者： Ravindra V. Gadhave Chaitali R. Gadhave Pritam V. Dhawale Department of Polymer and Surface Engineering Institute of Chemical Technology Mumbai India Department of Microbiology Savitribai Phule Pune University Pune India

Silane terminated prepolymers for adhesives, sealants and coatings are of great industrial importance. They are very important because of their low toxicity over polyurethanes, silicones, and solvent-based products. Hence, many pieces of literature which deal with the synthesis, properties and applications of this Silane terminated polymers hybrid system exist. Silylated polyether (MS polymers) and Silylated Polyurethane Polymers (SPUR) are the bases for numerous sealants, adhesives and coatings used worldwide. A hybrid system mixed with organic-polyurethane proportion and inorganic-alkoxysilane proportion combines the benefits of conventional polyurethane and silicone-based products. This article reviews the chemistry of MS polymers and SPUR and their advantages and disadvantages in silyl terminated prepolymer-based adhesives, sealants and coatings as well as provides information on different end applications.

关键词： silanes Silane Terminated Polyethers Silane-Terminated Polyurethanes Adhesives Sealants Coatings