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CATALYTIC ESTERIFICATION OF CARBOXYLIC ACIDS WITH ALCOHOLS BY SULFO-POLYVINYL CHLORIDE

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Chinese Journal of Reactive Polymers 1993年第2期2卷 182-186页

作者： Yu Shanxin ZHAO Zongbao yang jianwen (Department of Chemistry, Hunan Normal University, Changsha 410081, China)

Polyvinyl Chloride reacted with chlorosulfonic acid to from a polymer catalyst *** polymer catalyst was found to have high activity for resterification reaction between carboxylic acids and *** paper deals with the conditions in synthesis of n-butlyacetate catalyzed with *** PVC-SO3H was used as a catalyst for preparing 11 esters of acetic acid,propionic acid and butyric acid with the yields of 82-92%.

关键词：催化酯化作用羧酸乙醇磺基-聚乙烯氯化物

Numerical Simulation of Asphaltene Precipitation and Deposition during Natural Gas and CO_(2) Injection

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Fluid Dynamics & Materials Processing 2024年第2期20卷 275-292页

作者： Shasha Feng Yi Liao Weixin Liu jianwen Dai Mingying Xie Li Li Nanhai East Petroleum Research Institute Shenzhen Branch of CNOOC Ltd.Shenzhen518000China

Asphaltene deposition is a signiﬁcant problem during gas injection processes,as it can block the porous medium,the wellbore,and the involved facilities,signiﬁcantly impacting reservoir productivity and ultimate oil *** a few studies have investigated the numerical modeling of this potential effect in porous *** study focuses on asphaltene deposition due to natural gas and CO_(2) *** of the effect of gas injection on asphaltene deposition behavior have been made using a 3D numerical simulation *** results indicate that the injection of natural gas exacerbates asphaltene deposition,leading to a signiﬁcant reduction in permeability near the injection well and throughout the *** reduction in permeability strongly affects the ability of gas toﬂow through the reservoir,resulting in an improvement of the displacement *** displacement efﬁ-ciency of the injection gas process increases by up to 1.40%when gas is injected at 5500 psi,compared to the scenario where the asphaltene model is not ***_(2) injection leads to a miscible process with crude oil,extracting light and intermediate components,which intensiﬁes asphaltene precipitation and increases the viscosity of the remaining crude oil,ultimately reducing the recovery rate.

关键词： Reservoir simulation asphaltenes deposition natural gas injection CO_(2)injection

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光固化弹性体

光固化弹性体

2014第十五届中国辐射固化年会

作者： jianwen yang Sun Yat-sen University

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铝合金准确配料需考虑的若干因素

特种铸造及有色合金 2010年第10期30卷 977-978页

作者：张智龙杨建文山东兖矿轻合金公司

影响铝合金生产配料准确性的因素主要包括生产设备特征、衡器具及直读光谱仪误差、原辅材料质量及熔炼、铸造工艺特征等几个方面。配料时需对以上几个方面进行综合考虑和控制。

关键词：配料影响因素控制

对羟基苯甲酸存在下TiO_2粉末光催化还原Cr(Ⅵ)的动力学研究

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稀有金属 2005年第3期29卷 261-264页

作者：郭琳杨建文广东教育学院化学系广东广州510310 中山大学化学与化学工程学院广东广州510275

研究了对羟基苯甲酸存在下TiO2光催化还原Cr(Ⅵ)过程中不同对羟基苯甲酸浓度、Cr(Ⅵ)初始浓度及溶液初始pH值对Cr(Ⅵ)光降解速率的影响,认为TiO2悬浮体系能有效地光催化还原水溶液中的Cr(Ⅵ)离子,并得出TiO2光催化还原Cr(Ⅵ)过程符合L ... 详细信息

研究了对羟基苯甲酸存在下TiO2光催化还原Cr(Ⅵ)过程中不同对羟基苯甲酸浓度、Cr(Ⅵ)初始浓度及溶液初始pH值对Cr(Ⅵ)光降解速率的影响,认为TiO2悬浮体系能有效地光催化还原水溶液中的Cr(Ⅵ)离子,并得出TiO2光催化还原Cr(Ⅵ)过程符合L H动力学模型。反应体系中的Cr(Ⅵ)初始浓度及初始pH值对TiO2光催化还原Cr(Ⅵ)过程的速率有较大的影响。酸性条件有利于Cr(Ⅵ)的光催化还原。对羟基苯甲酸具有芳香族化合物的特殊结构,对TiO2光催化还原Cr(Ⅵ)过程有显著的促进作用。

关键词：光催化 Cr(Ⅵ) TiO2 对羟基苯甲酸

BICENTRAL　POLYMER　SUPPORTED　PHASE　TRANSFER　CATALYST　POLYSTYRENE－SUPPORTED　POLYETHYLENE　GLYCOL　AND　PYRIDINIUM　SALT

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Chinese Journal of Reactive Polymers 1996年第Z1期 92-98页

作者： yang jianwen(Institute of Polymer Science, Zhongshan University, Guangzhou 510275)Yu Shanxin(Department of Chemistry, HunanNormal University, Changsha 410081 )

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ＢＩＣＥＮＴＲＡＬＰＯＬＹＭＥＲＳＵＰＰＯＲＴＥＤＰＨＡＳＥＴＲＡＮＳＦＥＲＣＡＴＡＬＹＳＴＰＯＬＹＳＴＹＲＥＮＥ－ＳＵＰＰＯＲＴＥＤＰＯＬＹＥＴＨＹＬＥＮＥＧＬＹＣＯＬＡＮＤＰＹＲＩＤＩＮＩＵＭＳＡＬＴＹａｎｇＪｉａｎｗｅｎ（Ｉｎｓｔｉｔｕｔｅｏｆ...

关键词： Phase transfer catalyst Polymer-supported catalyst Polyethylene glycol (PEG) Pyridinium salt

Solution-processed amorphous gallium-tin oxide thin film for low-voltage, high-performance transistors

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Science China Materials 2019年第6期62卷 803-812页

作者： Jinhua Ren Kaiwen Li jianwen yang Dong Lin Haoqing Kang Jingjing Shao Ruofan Fu Qun Zhang Department of Materials Science National Engineering Laboratory for TFT-LCD Materials and TechnologiesFudan University

Gallium-tin oxide(GTO) semiconductor thin films were prepared by spin-coating with 2-methoxyethanol as the solvent. Their crystal structures, optical transparency,chemical states and surface morphologies, along with the electrical properties, were dependent on Ga contents and annealing temperatures. The optimized GTO channel layer was applied in the high-k Al2O3 thin film transistor(TFT) with a low operation voltage of 2 V, a maximum field-effect mobility of 69 cm^2 V^-1 s^-1, a subthreshold swing(SS) of 76 mV dec^-1, a threshold voltage of 0.67 V and an on-off current ratio of 1.8×10^7. The solution-processed amorphousGTO-TFTs would promote the development of low-consumption, low-cost and high performance In-free TFT devices.

关键词： GTO semiconductor films thin-film transistor stability Al2O3 dielectric

Impact of Blade-Flapping Vibration on Aerodynamic Characteristics of Wind Turbines under Yaw Conditions

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Energy Engineering 2024年第8期121卷 2213-2229页

作者： Shaokun Liu Zhiying Gao Rina Su Mengmeng Yan jianwen Wang College of Energy and Power Engineering Inner Mongolia University of TechnologyHohhot010051China Key Laboratory of Wind and Solar Energy Utilization Technology Ministry of EducationHohhot010051China

Although the aerodynamic loading of wind turbine blades under various conditions has been widely studied,the radial distribution of load along the blade under various yaw conditions and with blade flapping phenomena is poorly *** study aims to investigate the effects of second-order flapwise vibration on the mean and fluctuation characteristics of the torque and axial thrust of wind turbines under yaw conditions using computational fluid dynamics(CFD).In the CFD model,the blades are segmented radially to comprehensively analyze the distribution patterns of torque,axial load,and tangential *** following results are obtained.(i)After applying flapwise vibration,the torque and axial thrust of wind turbines decrease in relation to those of the rigid model,with significantly increased fluctuations.(ii)Flapwise vibration causes the blades to reciprocate along the axial direction,altering the local angle of attack and velocity of the blades relative to the incoming wind *** results in the contraction of the torque region from a circular shape to a complex“gear”shape,which is accompanied by evident oscillations.(iii)Compared to the tangential load,the axial load on the blades is more sensitive to flapwise vibration although both exhibit significantly enhanced *** study not only reveals the impact of flapwise vibration on wind turbine blade performance,including the reduction of torque and axial thrust and increased operational fluctuations,but also clarifies the radial distribution patterns of blade aerodynamic characteristics,which is of great significance for optimizing wind turbine blade design and reducing fatigue risks.

关键词： Wind turbine CFD numerical simulation aerodynamic characteristics yaw flapping vibration

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分数阶复合控制在光电稳定平台中的应用

电光与控制 2020年第1期27卷 73-78页

作者：杨建文任彦内蒙古科技大学信息工程学院

针对高精度光电稳定平台系统的跟踪精度易受到摩擦力矩和非线性干扰等因素的影响,运用加性分解理论将光电稳定平台系统分解为主系统和辅系统。主系统采用基于加速度的分数阶PID控制方法,确保视轴的跟踪精度。针对辅系统提出了基于速度... 详细信息

针对高精度光电稳定平台系统的跟踪精度易受到摩擦力矩和非线性干扰等因素的影响,运用加性分解理论将光电稳定平台系统分解为主系统和辅系统。主系统采用基于加速度的分数阶PID控制方法,确保视轴的跟踪精度。针对辅系统提出了基于速度信号的分数阶干扰观测器(FO-VDOB)的设计方法,利用分数阶的阶次能够在实数范围内任意选取的特点,可以更好地解决干扰抑制和估计补偿,保证视轴的稳定。结合分数阶理论设计分数阶滑模补偿器,在辅系统中进一步补偿未知的干扰。利用有限时间收敛理论和李雅普诺夫理论证明了系统在有限时间内达到了稳定。实验结果表明,该方法使得光电稳定平台系统对运动目标具有很高的跟踪精度。

关键词：稳定平台加性分解分数阶控制滑模控制干扰补偿