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Wide-Temperature-Range Dielectric Permittivity Measurement under High Pressure

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Chinese Physics Letters 2017年第4期34卷 13-17页

作者： Zhen Yuan Jin-Long Zhu Shao-Min Feng chang-chun wang Li-Juan wang Qing-Qing Liu chang-Qing Jin Department of Materials Science and Engineering Linyi University Linyi 276005 Center for High Pressure Science and Technology Advanced Research Beijing 100094 National Lab for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190

Two measurement systems are developed for in-situ dielectric property measurement under high pressure in a wide-temperature range from 77K to 1273 K. The high-temperature system ranging from room temperature up to 1273K is equipped with a hexahedron anvils press, while the low-temperature system ranging from liquid nitrogen temperature to normal condition is equipped using the piston cylinder setup with a specially designed sample chamber. Using these configurations, the dielectric property measurement of ferroelectrie BaTiO3 and multiferroie Tm0.5Gd0.5MnO3 compounds are demonstrated, which proves the validity of the systems through the tuning of the polarization and phase transition boundary by high pressure. These two systems will be equally applicable to a wide variety of electronic and transport property measurements of insulators, semiconductors, as well as battery materials.

关键词： der Wide-Temperature-Range Dielectric Permittivity Measurement under High Pressure BTO

Performance variability of Ba0.5Sr0.5Co0.8Fe0.2O3-δ cathode on proton-conducting electrolyte SOFCs with Ag and Au current collectors

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Rare Metals 2018年第8期37卷 633-641页

作者： Ting-Ting Wan An-Kang Zhu Hai-Bo Li chun-chang wang You-Min Guo Zong-Ping Shao Oumarou Savadogo School of Physics and Materials Science Anhui UniversityHefei 230601China State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemistry and Chemical EngineeringNanjing University of TechnologyNanjing 210009China Department of Chemical Engineering Curtin UniversityPerth W A 6845.Australia Laboratory of New Materials for Electrochemistry and Energy Polytechnique MontrealC.P.6079Succursale Centre-VilleMontr6alQC H3C 3A7Canada

Ba0.5Sr0.5Co0.8Fe0.2O3-δ （BSCF） is one of the most active cathode materials and shows significant hydration effect suggesting possible proton conductivity. In this study, the performance of BSCF cathode on a protonconducting BaZr0.1Ce0.7Y0.2O3-δ（BZCY） electrolyte with silver and gold current collectors was determined. The electrochemical characteristics of the symmetrical and anode-supported cell with diluted silver electrode, silver current collector or gold current collector on BSCF electrode were compared. The significant result is that, although the diluted silver electrode itself shows poor operation stability, the silver current collector has strong electrocatalytic contribution to the BSCF cathode performance on the proton-conducting electrolyte, leading to higher cell performance than that with the gold current collector.

关键词： Solid oxide fuel cell Proton conductor Agcurrent collector Operation stability

Efficiency for Gene Silencing Induction in Nicotiana Species by a Viral Satellite DNA Vector

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Journal of Integrative Plant Biology 2007年第12期49卷 1726-1733页

作者： You-Ping Xu Lu-Ping Zheng Qiu-Fang Xu chang-chun wang Xue-Ping Zhou Zu-Jian Wu Xin-Zhong Cai Institute of Biotechnology Zhejiang University Hangzhou 310029 China Centre of Analysis and Measurement Zhejiang University Hangzhou 310029 China Institute of Plant Virology Fujian Agriculture and Forestry University Fuzhou 350002 China

Virus-induced gene silencing （VIGS） is a useful technique for rapid plant gene function analysis. We recently reported a new VIGS vector modified from Tomato yellow leaf curl China virus （TYLCCNV） DNAβ （DNAm β）. In this study we compared in detail DNAmβ-induced gene silencing in four Nicotiana species including N. benthamiana, N. glutinosa, N. tabacum and N. paniculata. We found that DNAmβ-induced gene silencing in the four species was distinct in developing dynamics, tissue specificity, efficiency, and constancy in the plant life span. It was most efficient in N. benthamiana, where development of VIGS was most rapid, without tissue specificity and nearly 100% efficient. DNAmβ-induced gene silencing in N. glutinosa was also efficient despite being slightly less than in N. benthamiana. It initially occurred in veins, later was scattered to mesophyll, finally led to complete silencing in whole leaves. In both species, VIGS constantly expressed until the plants died. However, DNAmβ-mediated VIGS in the other two Nicotiana species, N. tabacum and N. paniculata, was significantly less efficient. It was strictly limited within the veins of the silenced leaves, and constantly occurred only over 3-4 weeks. The upper leaves that emerged later stopped showing the silencing phenotype. DNAmβ-induced gene silencing in N. benthamiana and N. glutinosa was not significantly influenced by the growth stage when the plants were agro-inoculated, and was not sensitive to high growth temperature up to 32℃. Our results indicate that this system has great potential as a versatile VIGS system for routine functional analysis of genes in some Nicotiana species.

关键词： DNAβ Nicotiana tobacco rattle virus tomato yellow leaf curl China virus virus-induced gene silencing.

Customer Segmentation of Credit Card Default by Self Organizing Map

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American Journal of Computational Mathematics 2018年第3期8卷 197-202页

作者： Hui Wu chang-chun wang Department of Mathematics Clark Atlanta University Atlanta GA USA International Monetary Fund Washington DC USA

In this paper we applied the technique of Self Organizing Map (SOM) to segment individuals based on their credit information. SOM is an unsupervised machine learning method that reduces data complexity and dimensionality while keeping sits original topology, which is superior to other dimension reduction methods especially when features in data have unclear nonlinear relations. Through this method we provide more clear and intuitive segmentation that other traditional methods cannot achieve.

关键词： Self Organizing Map Clustering Machine Learning Credit Default

Aza-Michael addition reactions between nitroolefins and benzotriazole catalyzed by MCM-41 immobilized heteropoly acids in water

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Chinese Chemical Letters 2013年第1期24卷 28-30页

作者： Shao-Lei Xie Yong-Hai Hui Xiang-Ju Long chang-chun wang Zheng-Feng Xie Key Laboratory of Oil & Gas Fine Chemicals Ministry of Education & Xinjiang Uyghur Autonomous RegionCollege of Chemistry and Chemical EngineeringXinjiang University

MCM-41 supported heteropoly acids （HPAs） catalysts were synthesized, characterized and their catalytic activity was evaluated in an aza-Michael addition reaction between nitroolefins and benzotriazole in water at room temperature. 50 wt% PW/MCM-41 showed the highest activity （up to 96% yield）. The catalyst was used in six consecutive experiments without obvious loss of activity, confirming the success of the anchoring process and the catalyst stability.

关键词： Aza-Michael additionMCM-41Heteropoly acidsHeterogenous catalysts

基于金/巯基相互作用的功能分子在磁性高分子复合微球表面可控组装研究

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高分子学报 2018年第8期28卷 1073-1080页

作者：万家勋孙璐艳汪长春聚合物分子工程国家重点实验室复旦大学高分子科学系上海200438

建立了一种基于金纳米粒子与巯基相互作用的在磁性高分子复合微球表面高效组装功能分子的新方法.首先制备了粒径均一的介孔磁性纳米粒子簇(MSP),利用蒸馏沉淀技术在MSP上包覆一层―S―S―键交联的聚甲基丙烯酸壳层(P(MAA-Cy)),并将直径1... 详细信息

建立了一种基于金纳米粒子与巯基相互作用的在磁性高分子复合微球表面高效组装功能分子的新方法.首先制备了粒径均一的介孔磁性纳米粒子簇(MSP),利用蒸馏沉淀技术在MSP上包覆一层―S―S―键交联的聚甲基丙烯酸壳层(P(MAA-Cy)),并将直径10~30 nm的金纳米粒子沉积在MSP@P(MAACy)复合微球表面,从而获得MSP@P(MAA-Cy)-Au NP复合微球.调控HAu Cl4的投料量可以控制金纳米粒子沉积数量和尺寸.利用金粒子和巯基之间的强相互作用,将巯基修饰的荧光分子快速可控组装在MSP@P(MAA-Cy)-Au NP微球上.作为模型示范,实现了一次在MSP@P(MAA-Cy)-Au NP微球上快速固定单种或多种功能分子,为即时、高效、定量在功能微球(靶向药物载体等)上修饰功能分子提供了一种可选择的解决方案.

关键词：磁性纳米粒子簇金纳米粒子复合微球荧光分子即时修饰高效组装

基于LASSO算法的恒星α元素丰度估计方法研究

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光谱学与光谱分析 2017年第1期37卷 278-282页

作者：卜育德潘景昌王春雨陈修梅山东大学(威海)数学与统计学院山东威海264209 山东大学(威海)信息工程学院山东威海264209 中国人民大学统计学院北京100872 山东青年政治学院信息工程学院山东济南250103

主要研究了一种新的基于LASSO算法的恒星α元素丰度估计方法。海量恒星的α元素(O,Mg,Si,Ca和Ti)丰度信息将有助于我们了解银河系的演化进程。但目前从中低分辨率光谱中确定α元素丰度的方法主要是模板匹配法,但该方法算法复杂,优化参... 详细信息

主要研究了一种新的基于LASSO算法的恒星α元素丰度估计方法。海量恒星的α元素(O,Mg,Si,Ca和Ti)丰度信息将有助于我们了解银河系的演化进程。但目前从中低分辨率光谱中确定α元素丰度的方法主要是模板匹配法,但该方法算法复杂,优化参数较为困难且对噪声敏感,因此有必要研究新的方法。实验结果显示,LASSO算法对ELODIE光谱的α丰度的估计精度为0.003(0.078)dex。为验证光谱分辨率变化对LASSO算法结果的影响,我们首先用ELODIE光谱通过高斯卷积得到了分辨率为42 000,21 000,10 500,4 200和2 100的光谱,然后使用LASSO算法估计α元素丰度,精度分别为0.003 3(0.078)dex,-0.05(0.059)dex,-0.007(0.060)dex,0.008 0(0.069)dex和-0.004 5(0.067)dex。上述结果证明LASSO算法对分辨率变化不敏感。为验证LASSO算法对信噪比变化的鲁棒性,使用ELODIE光谱分别构造了信噪比为30,25,20,15和5的光谱。LASSO算法在上述数据集上的精度分别为-0.002(0.076)dex,-0.09(0.073)dex,0.003 6(0.075)dex,0.007 6(0.078)dex和-0.009(0.08)dex,因而LASSO算法对信噪比变化不敏感。因此,LASSO算法适用于低分辨率低信噪比的LAMOST和SDSS光谱。LASSO算法在SDSS光谱上的估计精度为0.003 7(0.097)dex,而在球状星团和疏散星团成员星上的结果显示LASSO算法给出的丰度与文献给出α丰度值误差在1σ以内。因此,LASSO算法能够用于估计恒星的α元素丰度。

关键词： LASSO α元素丰度线性回归特征提取

Efficient and simple synthesis of B_(2)O_(3)-Al_(2)O_(3)nanocomposites assisted by deep eutectic solvent for production of 5-hydroxymethylfurfural from glucose

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Nano Research 2025年第1期18卷 236-248页

作者： Yuchen wang Kai Rong Shanlei chang Youxing Fang Shaojun Dong State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China College of Chemistry Jilin UniversityChangchun 130012China

The catalytic conversion of glucose to high valueadded platform chemical 5-hydroxymethylfurfural(HMF)is a promising biorefinery process,and alumina-boria catalysts are considered to be green and mild solid acid catalysts for this catalytic ***,compared to the common synthesis methods with complicated steps,we reported a simple and efficient strategy to prepare B_(2)O_(3)-Al_(2)O_(3)nanocomposites by calcining cost-effective glucose-urea deep eutectic solvent(DES)solution containing the *** prepared B_(2)O_(3)-Al_(2)O_(3)nanocomposites exhibited an open three-dimensional skeleton and two-dimensional porous lamellar substructure,endowing them with a high specific surface area(228.27 m2/g).The introduction of boron changed the ratios of different aluminum species(AlⅣ,AlⅤ,and AlⅥ)and borate species(BO3 and BO4),thus further affecting the acidity and the types of acid sites of the *** prepared B_(2)O_(3)-Al_(2)O_(3)bifunctional acid catalysts possessing abundant Lewis acid sites and adjustable Brønsted acid sites showed complete glucose conversion and 55.38%of HMF yield under the optimum *** study proposed a concise method to synthesize alumina-boria solid acid catalysts assisted by glucose-urea *** hope to extend the application and prospect of this efficient and simple synthesis strategy.

关键词： 5-hydroxymethylfurfural(HMF) deep eutectic solvent glucose alumina-boria acid catalyst

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炮载捷联惯导晃动误差补偿方法

中国惯性技术学报 2017年第1期25卷 37-42页

作者：王志伟秦俊奇杨功流石志勇狄长春王风杰军械工程学院北京航空航天大学陕西华阴63870部队

以某型自行火炮为研究对象,分析了其在匀速直线行驶过程中车体晃动的特点。提出了利用加速度信息修正陀螺信息的晃动补偿新方法,并详细推导了补偿公式,利用传统解析法实现了自行火炮在匀速直线行驶条件下粗对准。仿真结果表明,利用加速... 详细信息

以某型自行火炮为研究对象,分析了其在匀速直线行驶过程中车体晃动的特点。提出了利用加速度信息修正陀螺信息的晃动补偿新方法,并详细推导了补偿公式,利用传统解析法实现了自行火炮在匀速直线行驶条件下粗对准。仿真结果表明,利用加速度计信息可以准确得出当前姿态角和角速度,并且能够有效补偿陀螺晃动误差。在跑车试验中,首先利用FIR数字滤波器处理加速度计输出信息,然后用所提补偿方法补偿陀螺输出,结果表明在匀速直线行驶条件下,经过晃动补偿后传统解析式粗对准的精度与未经补偿的惯性系粗对准的精度相当,水平失准角均优于0.1021mil,航向失准角优于3.8603mil,表明该方法具有良好的工程适用性。

关键词：晃动补偿捷联惯导粗对准 FIR数字滤波