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Facial Preparation of Magnetic Lipase as Efficient Biocatalyst to Resolute Esters Enantioselectively

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Chemical Research in Chinese Universities 2015年第6期31卷 997-1002页

作者： ZHANG Yanmei QUAN Chunshan liu baoquan FAN Shengdi College of Life Science Dalian Nationalities University Dalian 116600 P R. China

Magnetic lipase was prepared by a facial and cost-effective method. Lipase from Pseudomonase cepacia was covalently linked to Fe304 nanoparticles, which were produced by co-precipitating Fe^2＋ and Fe^3＋ ions in ammonia solution and subsequent coating with 3,4-dihydroxylaldehyde. Magnetic Fe304 nanoparticles modified with 3,4-dihydroxylaldehyde bonded lipase efficiently（47 mg/g）. The resulting magnetic-lipase is active（0.68 μmol·min^-1·mg^-1） and enantioselective（e.e, of the product 〉98%） in the hydrolysis of racemic 1-phenylethyl acetate. Furthermore, as a heterogeneous catalyst, the magnetic-lipase can be magnetically recycled, and a retained activity of 48% was obtained even after 6 cycles.

关键词： Covalent attachment 3,4-Dihydroxylaldehyde Enantioselective hydrolysis Lipases from Pseudomonasecepacia Fe3O4 nanoparticle Recycle

Oriented growth and assembly of zeolite crystals on substrates

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Chinese Science Bulletin 2008年第6期53卷 801-816页

作者： ZHOU Ming ZHANG baoquan liu XiuFeng School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

The aligned array and thin film of zeolites and molecular sieves possess a variety of potential applica- tions in membrane separation and catalysis, chemical sensors, and microelectronic devices. There are two main synthesis methods for manufacturing the aligned arrays and thin films of zeolites and mo- lecular sieves, i.e. in situ hydrothermal reaction and self-assembly of crystal grains on substrates. Both of them have attracted much attention in the scientific community worldwide. A series of significant progress has been made in recent years. By the in situ hydrothermal synthesis, the oriented nucleation and growth of zeolite and molecular sieve crystals can be achieved by modifying the surface properties of substrates or by changing the composition of synthesis solutions, leading to the formation of uni- formly oriented multicrystal-aligned arrays or thin films. On the other hand, the crystal grains of zeo- lites and molecular sieves can be assembled onto the substrate surface in required orientation using different bondages, for instance, the microstructure in the array or thin film can be controlled. This review is going to summarize and comment the significant results and progress reported recently in manufacturing highly covered and uniformly aligned arrays or thin films of zeolites and molecular sieves. It involves (1) in situ growth of highly aligned zeolite arrays and thin films via embedding func- tional groups on the substrate surface, modifying the surface microstructure of substrates, as well as varying the composition of synthesis solutions; (2) assembly of zeolite and molecular sieve crystals on various substrates to form aligned arrays and thin films with full coverage by covalent, ionic, and in- termolecular coupling interactions between crystals and substrates; (3) coupling surface assembly with microcontact printing or photoetching technique to produce patterned zeolite arrays and thin films. Finally, the functionality and applications of zeoli

关键词：沸石分子筛表面组装水热合成晶体生长

Decoration of carbon encapsulated nitrogen-rich MoxN with few-layered MoSe2 nanosheets for high-performance sodium-ion storage

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Journal of Energy Chemistry 2022年第11期31卷 332-340,I0009页

作者： Tao Lu baoquan liu Fanyan Zeng Guo Cheng Shile Chu Meilan Xie Zhi Chen Zhaohui Hou School of Materials Science and Engineering Nanchang Hangkong UniversityNanchang 330063JiangxiChina Jiangxi Key Laboratory of Nanomaterials and Sensors School of PhysicsCommunication and ElectronicsJiangxi Normal UniversityNanchang 330022JiangxiChina Key Laboratory of Hunan Province for Advanced Carbon-based Functional Materials School of Chemistry and Chemical EngineeringHunan Institute of Science and TechnologyYueyang 414006HunanChina

Transition metal nitrides have become the focus of research in sodium ion batteries(SIBs)due to their unique metal properties and high theoretical ***,the low actual capacity is still the main bottleneck for their ***,using Mo-aniline frameworks as precursors,the carbon encapsulated nitrogen-rich Mo_(x)N is decorated by few-layered MoSe_(2) nanosheets(MoSe_(2)@Mo_(x)N/C-I)after the facile calcinating,selenizing,and *** carbon encapsulation can effectively strengthen the structural stability of Mo_(x)*** nitrogen-rich Mo_(x)N and decoration of few-layered MoSe_(2) can create rich heterointerfaces and extra active sites for rapid sodium-ion storage,thus promoting reaction kinetics and improving actual *** MoSe_(2)@Mo_(x)N/C-I as an anode achieves a large reversible capacity of 522.8 mAh g^(-1)at 0.1 A g^(-1),and 254.3 mAh g^(-1)capacity is obtained after 6000 cycles at 5.0 A g^(-1),showing signally improved sodium-ion storage *** storage mechanisms and kinetic behaviors are described systematically via the advanced testing techniques and density functional theory(DFT)*** is found that the nitrogen-rich Mo_(x)N as the substrate is the basis of long cycling stability,and the few-layered MoSe_(2) are the key to improving actual *** work indicates that the decoration of few-layered selenides has a broad application prospect in high-performance metal-ion batteries.

关键词： Few-layered MoSe_(2)nanosheets Decoration Carbon encapsulation Nitrogen-rich MoxN Sodium ion batteries

Simulation experiment on hydrocarbon generating potential of various source rocks on the northern margin of the Qaidam Basin,Qinghai,China

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Chinese Journal Of Geochemistry 2008年第4期27卷 412-419页

作者： LI Xin WANG Dongliang liu baoquan REN Chunling GUO Jianying SU Xuefeng WANG Jian China University of Minning ＆ Technology Beijing 100083 China Exploration ＆ Development Research Institute Huabei Oilfield Company Renqiu 062552 China China University ofGeosciences Beijing 100083 China Research Institute of Petroleum Exploration ＆ Development Langfang 065000 China

The northern margin of the Qaidam Basin is one of the main oil-gas exploration areas in western China,where source rocks are composed mostly of Middle and Lower Jurassic dark mud shale,carbargillite and coal. A large number of subsurface and outcrop samples differing in lithology with different types of organic matter were selected for resource evaluation,research and calculation. And among them,13 samples were used for simulation experiment on hydrocarbon generating potential of various source rocks. At first,two kinds of heating modes were compared through simulation experiment,including single temperature-step heating and continual heating. Perhaps,the process of hydrocarbon generation and expulsion occurred naturally between a close system and an open system. In addition,the first heating mode was convenient,and all its reaction products were involved in the whole thermal evolution,and the final simulation experimental results were basically in consistency with the natural evolution trend. Therefore,the first heating mode was adopted and the hydrocarbon yield of every sample was worked out. Accord-ing to the type and lithology of organic matter and the hydrocarbon yield of samples for simulation experiment,hy-drocarbon generation and expulsion mode with three kinds of lithology and five types of source rock has been estab-lished to provide the basis for hydrocarbon generation evaluation,research and resource calculation.

关键词：中国青海油田碳氢化合物

Effects of uranium on hydrocarbon generation of hydrocarbon source rocks with type-Ⅲ kerogen

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Science China Earth Sciences 2014年第8期57卷 1168-1179页

作者： MAO GuangZhou liu ChiYang ZHANG DongDong QIU XinWei WANG JianQiang liu baoquan liu JingJiang QU ShaoDong DENG Yu WANG FeiFei ZHANG Can Shandong Provincial Key Laboratory of Depositional Mineralization & Sedimentary Minerals College of Geological Sciences & Engineering Shandong University of Science and Technology State Key Laboratory of Continental Dynamics Institute of Petroliferous Basin of Northwest University Shandong Provincial Key Laboratory of Depositional Mineralization & Sedimentary Minerals College of Geological Sciences &Engineering Shandong University of Science and Technology Guangzhou Institute of Geochemistry Chinese Academy of Sciences Exploration and Development Research Institute of Huabei Oilfield Company PetroChina Research Institute of Petroleum Exploration & Development

Organic-inorganic interaction exists universally and is important in the process of mineral resources *** is the essential reason why organic oil,gas,coal and inorganic uranium coexist,accumulate,and mineralize in the same sedimentary ***-generating simulation experiment was conducted using low-mature hydrocarbon source rock containing kerogen type III with uranium(UO2CO3 solution)added to study the effects of uranium on the hydrocarbon generation of hydrocarbon source *** results show that uranium can enhance the yield of gas hydrocarbon,promote the total gas output,and increase the total hydrocarbon production(mass or volume).Uranium may lower the hydrocarbon generation threshold temperature and lead to the generation of liquid hydrocarbon in the relative low temperature of hydrocarbon source *** can enhance the yield of saturated hydrocarbon,promote the low molecular weight hydrocarbons generating,and in turn increase the content of CH4 and the content of dry gas of the generated *** is one of the potential inorganic accelerating factors of the immature hydrocarbons.

关键词： hydrocarbon generation simulation uranium source rocks maturity organic-inorganic interactions

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基于压缩感知的电能质量扰动数据稀疏分析与改进重构算法

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电工技术学报 2018年第15期33卷 3461-3470页

作者：刘嫣汤伟刘宝泉陕西科技大学电气与信息工程学院西安710021

基于压缩感知(CS)的电能质量扰动(PQD)信号多采用DFT基进行稀疏分析。但此方法存在频谱泄露问题,降低了原始数据的稀疏性,易造成后续重构算法稀疏度过度估计、执行效率下降。针对上述问题,在对PQD信号进行DFT稀疏分析的基础上,提出了一... 详细信息

基于压缩感知(CS)的电能质量扰动(PQD)信号多采用DFT基进行稀疏分析。但此方法存在频谱泄露问题,降低了原始数据的稀疏性,易造成后续重构算法稀疏度过度估计、执行效率下降。针对上述问题,在对PQD信号进行DFT稀疏分析的基础上,提出了一种对频谱泄露具有免疫能力的改进重构算法。首先对4种典型PQD信号进行了幅度谱推导,详细分析了信号相关参数与稀疏特性的关系。其次在此基础上对自适应匹配追踪(SAMP)算法进行改进,并提出频谱能量差的概念。频谱能量差可以反映出相邻迭代过程中重构信号频谱能量的变化,将该差值作为SAMP算法的迭代终止条件时,能有效地避免稀疏度过度估计并提高运算效率。最后,通过对比实验,验证了改进SAMP算法的优越性。

关键词：压缩感知电能质量扰动 DFT 稀疏性重构算法

原边串联型LLC变换器拓扑及其频率自适应追踪方法

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高电压技术 2023年第12期49卷 5114-5125页

作者：刘宝泉韩猛王伟陕西科技大学电气与控制工程学院西安710021

为了拓宽传统LLC变换器的增益范围,多采用脉冲宽度调制(pulse width modulation,PWM)变换器与LLC变换器级联的两级式拓扑,其中LLC变换器开环工作于谐振频率点,PWM变换器负责闭环稳压。由于PWM变换器承担了全部负载功率,效率损失较大,且... 详细信息

为了拓宽传统LLC变换器的增益范围,多采用脉冲宽度调制(pulse width modulation,PWM)变换器与LLC变换器级联的两级式拓扑,其中LLC变换器开环工作于谐振频率点,PWM变换器负责闭环稳压。由于PWM变换器承担了全部负载功率,效率损失较大,且LLC谐振腔参数受电路杂散电感、器件批次一致性等影响,谐振频率点常偏离于预设值,导致整机效率进一步下降。针对上述问题,提出了一种原边串联型LLC变换器拓扑,将同步Buck变换器的输出端与全桥LLC变换器的任一桥臂串联,通过调节Buck输出电压改变LLC谐振腔输入电压幅值,Buck仅承担部分负载功率即可实现整机宽增益范围调节。对于谐振频率点偏离问题,提出了一种频率自适应追踪方法,结合LLC在不同谐振状态下的换流特性,根据副边整流管通流时间,无需谐振状态判断便可直接计算频率调节值,进行谐振频率追踪控制。最后搭建一台28 V/1 kW实验样机,在240~380 V输入条件下,Buck变换器最多仅承担45%的负载功率,同时可以准确追踪变换器的谐振频率点。变换器整机峰值效率为97.39%,相较传统两级式拓扑效率最大提升2.32%。

关键词：宽增益范围同步Buck变换器 LLC变换器软开关频率追踪

Assessment in a micro-¯o-perspective——Interview with *** Bachman&*** Damb■ck

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外语测试与教学 2019年第2期 1-8页

作者：刘芹刘宝权上海理工大学外语学院上海200093 上海财经大学外国语学院上海200433

笔者二人于21世纪初在上海外国语大学攻读博士学位,师从邹申教授。读博期间,博士生语言测试课程的主要教材为Lyle Bachman教授1990年出版的 Fundamental Considerations in Language Testing 。那时,Bachman教授于我们而言是高山仰止、... 详细信息

笔者二人于21世纪初在上海外国语大学攻读博士学位,师从邹申教授。读博期间,博士生语言测试课程的主要教材为Lyle Bachman教授1990年出版的 Fundamental Considerations in Language Testing 。那时,Bachman教授于我们而言是高山仰止、高不可攀的学术泰斗,从未想到我们在之后近20年的时间里会有那么多的交集。2004年,我们去北京参加“第四届中国英语教学国际研讨会”,欣喜地发现偶像也在会场。作为语言测试领域的新人,我们鼓足勇气与Bachman教授交流学术想法,并在会后留下了珍贵的合影。2018年,Bachman教授再次来到北京,参加“语言测试与评价国际研讨会”并发表主旨演讲。没有想到的是,他在大会上展示了和我们的两张合影,这让我们万分感动——多年后他依然保留着我们的照片!自2004年相识后,我们俩先后与他联系,于2006年和2008年赴他所在的美国加州大学洛杉矶分校访学。访学期间,我们积极参与了他提出的检验测试结果解释和测试使用合理性的理论——测试使用论证(Assessment Use Argument,简称AUA)的讨论。2008年初, Bachman教授应我们之邀为上海理工大学和上海财经大学的师生开展语言测试的讲座,受到了热烈欢迎。多年来,我们一直通过参加学术会议或邮件往来与Bachman教授保持密切的联系。无论是学术研究或是其他事宜,只要我们有所求,他都不吝赐教,并与我们分享点点滴滴的喜悦。2018年底,获悉他和夫人*** Damb ck再次来到中国,我们便再邀请他们莅临上海理工大学解读最新的研究成果,他们欣然接受。期间,我们对他们进行了专访,访谈内容如下.

关键词：上海外国语大学邹申博士学位

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干涉合成孔径雷达复图像配准解析搜索方法

数据采集与处理 2008年第6期23卷 646-651页

作者：刘宝泉冯大政武楠华东电子工程研究所合肥230031 西安电子科技大学雷达信号处理国家重点实验室西安710071

图像配准是干涉SAR数据处理中关键步骤之一,它的处理精度直接影响着高程重建的质量。为了克服经典方法带来误差的影响,本文构建了一种解析代价函数,利用双迭代优化算法与弦割法求取亚像元级偏移量,实现了在连续域内搜索,避免了传统的在... 详细信息

图像配准是干涉SAR数据处理中关键步骤之一,它的处理精度直接影响着高程重建的质量。为了克服经典方法带来误差的影响,本文构建了一种解析代价函数,利用双迭代优化算法与弦割法求取亚像元级偏移量,实现了在连续域内搜索,避免了传统的在离散域搜索带来的误差,提高了配准精度,在插值意义上,配准精度达到最优。基于实测数据的实验结果表明,该算法具有较高精度。

关键词：干涉合成孔径雷达亚像元级配准解析的代价函数双迭代优化