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硝基芳香族化合物密度、爆速和撞击感度的量子化学及QSPR研究(英文)

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火炸药学报 2008年第5期31卷 28-32页

作者：来蔚鹏廉鹏王伯周葛忠学张志忠薛永强庞先勇西安近代化学研究所陕西西安710065 太原理工大学应用化学系山西太原030024

运用Gaussian98等程序对32种描述符进行了计算,采用Cerius2程序包中的QSPR方法建立了硝基芳香族化合物密度、爆速和撞击感度与32种描述符之间的构效关系式,相关系数R分别为0.951、0.992和0.92,预测值与实验值之间的平均误差分别为1.92%... 详细信息

运用Gaussian98等程序对32种描述符进行了计算,采用Cerius2程序包中的QSPR方法建立了硝基芳香族化合物密度、爆速和撞击感度与32种描述符之间的构效关系式,相关系数R分别为0.951、0.992和0.92,预测值与实验值之间的平均误差分别为1.92%、0.93%和5.10%;与Kamlet方法计算的爆速值相比,用QSPR方法计算的爆速值准确性较高。此外,还找到了影响硝基芳香族化合物密度、爆速和撞击感度的主要因素,以及可以同时使密度和爆速增大而撞击感度降低的因素。

关键词：量子化学 QSPR 硝基芳香族化合物密度爆速撞击感度

Room-temperature terahertz detection based on CVD graphene transistor

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Chinese Physics B 2015年第4期24卷 378-382页

作者：杨昕昕孙建东秦华吕利苏丽娜闫博李欣幸张志鹏方靖岳 Key Laboratory of Nanodevices and Applications Suzhou Institute of Nano-tech and Nano-bionicsChinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory of Advanced Process Control for Light industry Department of Electronic Engineering Jiangnan University College of Science National University of Defense Technology

We report the fabrication and characterization of a single-layer graphene field-effect terahertz detector, which is cou- pled with dipole-like antennas based on the self-mixing detector model. The graphene is grown by chemical vapor deposi- tion and then transferred onto an SiO2/Si substrate. We demonstrate room-temperature detection at 237 GHz. The detector could offer a voltage responsivity of 0.1 V/W and a noise equivalent power of 207 nW/Hz 1/2. Our modeling indicates that the observed photovoltage in the p-type gated channel can be well fit by the self-mixing theory. A different photoresponse other than self-mixing may apply for the n-type gated channel.

关键词： graphene field effect transistor self-mixing terahertz detection

复杂稀土锆酸盐陶瓷的结构及其介电性能研究(英文)

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稀有金属材料与工程 2012年第S3期41卷 483-486页

作者：刘玲马壮王富耻朱时珍徐强北京理工大学北京100081 冲击环境材料技术重点实验室北京100081

采用溶胶-凝胶法(sol-gel)合成了一系列复杂的稀上锆酸盐陶瓷粉体,(La_(0.4)Sm_(0.5)Yb_(0.1))_2Zr_2O_7、(La_(0.4)Sm_(0.5)Yb_(0.1))_2(Zr_(0.7)Ce_(0.3)O_7、((La_(0.4)Sm_(0.5)Yb_(0.1))_2Zr_(0.7)Ce_(0.4))_2O_(7.4)和(La_(0.4)Sm_(0.5)Yb_(0.1))_2(Zr_(0.7)Ce_(0.3)0_7 3。利用X射线衍射(XRD)仪及场发射扫描电镜(SEM)对各粉体和块体的微观结构进行了表征,采用阻抗分析仪测试了各陶瓷的介电性能。结果表明,复杂稀土锆酸盐均具有单一的焦绿石结构,其介电常数几乎与频率无关,并随Ce^(4+)含量的增加而逐渐降低,但当A位掺入Sr^(2+)时,材料的介电常数增大:同时,焦绿石结构材料的介电常数随r(A^(3+))/rB^(4+))值的增大而上升,这可能与结构中氧空位的有序程度有关。

关键词：复杂稀上锆酸盐介电性能热障涂层 sol-gel

Modeling of Operators' Workload in a Nuclear Power Plant

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Engineering Sciences 2008年第1期6卷 31-37页

作者： Dai Licao Zhang Li OuYang Jun Huang Shudong Information Physics Engineering School of Central South University Changsha 410081 Human Factor Institute of Nanhua University Hengyang 421001 China Graduate School of Energy Science Kyoto University Japan

Accidents in a nuclear power plant are coped with by operators in the main control room (MCR). An analysis of the workload of operators in a MCR after the happening of initiating events is helpful to the alleviation of human errors and to the promotion of training efficiency. This paper establishes a framework of how man is located in a man-machine interface of a nuclear power plant (NPP) as well as a simulation of the man-machine scenario in accidents in NPPs, including the simulation of the operators' task and cognitive work and the establishment of task analysis. On the basis of the above, a model of the dynamic changes of the operators' tasks is constructed and a computation of operators' workload is conducted.

关键词： nuclear safety management man-machine scenario operators' workload human error

Huberized Multiclass Support Vector Machine for Microarray Classification

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自动化学报 2010年第3期36卷 399-405页

作者： LI Jun-Tao JIA Ying-Min The Seventh Research Division Beihang University Beijing100191 P. R. China

This paper proposes a new multiclass support vector machine(SVM)for simultaneous gene selection and microarray classification. Combining the huberized hinge loss function and the elastic net penalty, the proposed SVM can perform automatic gene selection and encourages a grouping effect. The coefficient paths of the proposed SVM are shown to be piecewise linear with respect to the single regularization parameter, based on which the solution path algorithm is developed with low computational complexity. Experiments performed on the leukemia data set are provided to verify the obtained results

关键词：基因支持向量机计算方法路径系数

An Improved Elastic Net for Cancer Classification and Gene Selection

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自动化学报 2010年第7期36卷 976-981页

作者： LI Jun-Tao JIA Ying-Min The Seventh Research Division Beihang University (BUAA) Beijing 100191 P.R.China

This paper presents an improved elastic net to identify relevant genes for cancer *** introducing the data-driven weight coe-cients, the improved elastic net can adaptively select genes in groups and reduce the shrinkage bias for the coe-cients of significant genes. Moreover, the irrelevant observations on the augmented dataset are removed and the computational complexity is largely reduced. Experiment results on the acute leukaemia data are provided to verify the proposed method.

关键词：癌症弹性网络基因组计算方法

Synthetic subnanochannels in porous aromatic frameworks accelerate selective water permeation in membrane desalination

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Science China Materials 2022年第7期65卷 1920-1928页

作者： Lei Wang Panpan Zhang Kaikai Chen Junchao Dong Feng Luo Qinglin Huang Zhixia Sun Xiaoqin Zou Guangshan Zhu Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education Faculty of ChemistryNortheast Normal UniversityChangchun 130024China Institute of Chemical and Industrial Bioengineering Jilin Engineering Normal UniversityChangchun 130052China State Key Laboratory of Separation Membranes and Membrane Processes Tiangong UniversityTianjin 300387China Science and technology on Reactor System Design technology Laboratory Nuclear Power Institute of ChinaChengdu 610213China

Creation of freeways in a membrane accelerates water transport for efficient desalination;however,the synthesis of target membrane materials is very *** the present study,the molecular-design strategy is developed for the synthesis of porous aromatic framework(PAF)membranes with rigid and open networks to regulate water ***-based monomers in triangle shape are designed for the construction of PAF-98 and its sister frameworks,and these PAF membranes are formed through trifluoromethanesulfonic acid *** rigidity and geometry of the monomers endow PAFs with unique structures of connected pores with edging size(4.5–6.7Å)between water(2.8Å)and hydrated sodium molecules(7.2Å),enabling effective differentiation of water and *** fabricated membranes with high flexibility and continuity are ideal for water desalination,and reverse osmosis experiments demonstrate that the three PAF membranes are selective for permeation of water molecules over hydrated sodium *** water flux of 547.1 L m^(-2) h^(-1) and high rejection degree of 90%are obtained on a representative membrane of PAF-98-E;and the desalination performance is superior to currently available membrane ***,PAF-98-E membrane is capable of rejecting various cations with high efficiency in real seawater,holding great promise in practical water desalination application.

关键词： porous aromatic framework water sieving reverse osmosis molecular design membrane desalination

Current Activity Characteristics of the Fault Zone Along the Northern Margin of West Qinling Range Revealed by GPS Measurement

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Earthquake Research in China 2000年第2期14卷 6-15页

作者： Li Yanxing Hu Xinkang and Kang LaixunFirst Crustal Deformation Monitoring Center, CSB, Tianjin 300180, China Lanzhou Institute of Seismology, CSB, Lanzhou 730000, China First Crustal Deformation Monitoring Center CSBTianjin 300180China Lanzhou Institute of Seismology CSBLanzhou 730000China

The fault zone along the northern margin of West Qinling Range is a major active fault zone in the key seismic monitoring area in the southeastern part of Gansu Province. In order to study the current activity characteristics of this fault, GPS monitoring network has been arranged along both sides of the fault and 3 measurements have been made from 1996 to 1998. The result indicates that obvious differential movement exists along the north and south sides of the fault and the eastward movement on the south side is 3.8 mm/a larger than that on the north side. In the GPS network, the shortened side is generally in the trend of EW and the extended side is basically NW to SE. The principal compressional stress trend in this area is about EW and the sinistral motion is obvious in the eastern part of the fault (near Wushan). The measured results also indicate that the displacement rate has decreased by 50% and the compressional strain has increased by 100% as compared the data of 1997 -1998 with those of 1996-1997, which shows that the compressional stress field in this region is intensifying and the next earthquake might be developing at present.

关键词： GPS measurement Fault activity characteristics Strain field analysis

Stability Analysis of Continuous-time Iterative Learning Control Systems with Multiple State Delays

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自动化学报 2010年第5期36卷 696-703页

作者： MENG De-Yuan JIA Ying-Min DU Jun-Ping YU Fa-Shan The Seventh Research Division Beihang University (BUAA) Beijing 100083 P. R. China Beijing Key Laboratory of Intelligent Telecommunications Software and Multimedia School of Computer Science and Technology Beijing University of Posts and Telecommunications Beijing 100876 P.R. China School of Electrical Engineering and Automation Henan Polytechnic University Jiaozuo 454000 P. R. China

This paper presents a stability analysis of the iterative learning control (ILC) problem for continuous-time systems with multiple state delays, especially when system parameters are subject to polytopic-type uncertainties. Using the two-dimensional (2-D) analysis approach to ILC, the continuous-discrete Roesser's type linear systems are employed to describe the entire learning dynamics of time-delay systems (TDS) with the development of an expanding operator. Based on such Roesser systems, the 2-D system theory is first used to develop a necessary and sufficient condition for the asymptotic stability of ILC, and then the robustH∞ control theory is combined to provide a sufficient condition in terms of linear matrix inequalities (LMIs) for the monotonic convergence of ILC. It is shown that learning gains can be determined by solving LMIs, which ensure the control input error converges monotonically to zero as a function of iteration. Simulation results show that a robust asymptotically stable ILC scheme can become robustly monotonically convergent by adding the P-type learning gains that satisfy a set of LMIs, which can also improve the convergence rate greatly.

关键词：连续系统稳定性自动化 TDS