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用摄像机和计算机记录物体的3维运动

物理实验 2002年第9期22卷 38-40页

作者：司丽荣张竞夫北京石油化工学院数理部北京10261

介绍了用摄像机和计算机记录 3维物体运动的实验方法 ,以及实验中的关键环节 :对系统定标和确定时间坐标起点 .用这种方法研究了球面摆的运动规律。

关键词：记录 3维运动摄像机球面摆物体运动运动规律

Cloning and characterization of an up-regulated GA 2.-oxidase gene in hybrid maize

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Progress in Natural Science:Materials International 2009年第2期19卷 161-166页

作者： Jinkun Du,Yingyin Yao,Zhongfu Ni,Qixin Sun Department of Plant Genetics & Breeding and State Key Laboratory for Agrobiotechnology,Key Laboratory of Crop Genomics and Genetic Improvement,Ministry of Agriculture/beijing Key Laboratory of Crop Genetic Improvement,china Agricultural {2.,beijing 100094,china [a]Department of Plant Genetics & Breeding and State Key Laboratory for Agrobiotechnology Key Laboratory of Crop Genomics and Genetic Improvement Ministry of Agriculture/Beijing Key Laboratory of Crop Genetic Improvement China Agricultural University Beijing 100094 China

Previous studies revealed that GA content and metabolism are positively correlated with a faster shoot growth rate of hybrid,and recently,genes participating in both GA biosynthesis and GA response pathways were also found to be differentially expressed between wheat hybrid and its parental inbreds. In this study,an up-regulated GA 2.-oxidase gene in a maize hybrid,designated ZmGA2.,was cloned. ZmGA2. contains an open reading frame (ORF) encoding 391 amino acid residues. BLASTX searches in GenBank revealed that the ZmGA2. is homologous to the sequences of GA2.ox proteins from different species,and analysis also indicated that ZmGA2. had typical features of GA 2.-oxidase proteins,including a "LPWKET" sequence. Semi-quantitative RT-PCR analysis showed that ZmGA2. was expressed in different tissues and/or organs. The expression level of ZmGA2. in the hybrid was higher than that in two parents (in roots,leaves,stems and embryo,and ears). The abundance of ZmGA2. transcript was equal to that of the highly expressed parents,which provided molecular evidence for the observed GA content heterosis in maize hybrids.

关键词： GA 2.-oxidase Gene expression Maize Heterosis

Robust Tomlinsion-Harashima precoding design with outdated CSIT

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The Journal of china Universities of Posts and Telecommunications 2010年第2期17卷 59-62页

作者： WANG Xu-zhen ,NIU Kai,HE Zhi-qiang,YU Guang-wei,WU Wei-ling Key Laboratory of Universal Wireless Communications,Ministry of Education,beijing university of Posts and Telecommunications,beijing 100876,china [a] Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts Telecommunications Beijing 100876 China

The channel state information at transmitter （CSIT） acquisition plays a key role in the multi-input multi-output （MIMO） system, especially for the precoding schemes. However it is unrealizable to acquire perfect CSIT in practice. In this article, an effective and practical dynamic CSIT model is introduced to acquire imperfect channel state information. For practicability, the channel temporal and spatial correlations are considered and the channel estimate and its error covariance are obtained by utilizing the outdated channel state information. Based on the dynamic CSIT mode, closed-form solution of robust Tomlinsion-Harashima precoding （THP） is derived by a Lagrangian approach. Numerical simulations are presented to demonstrate the performance.

关键词： channel estimation imperfect CSIT robust THP

Photocatalytic performance of TiO_2.thin films connected with Cu micro-grid

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Science china(Technological Sciences) 2009年第8期52卷 2175-2179页

作者： ZHU HaiLing1, ZHANG JunYing1, WANG TianMin1, WANG LiuGang1, LAN Xiang1 & HUANG BaiBiao2.1 School of Science, Beihang university, beijing 100191,{2. 2.State Key Laboratory of Crystal Materials, Shandong university, Ji’nan 2.0100,{2. School of Science Beihang University Beijing 100191 China State Key Laboratory of Crystal Materials Shandong University Ji’nan 250100 China

Aiming at reducing the recombination of photo-induced carriers in semiconductor photocatalytic process, we prepared TiO2.thin film with its surface modified by a connected Cu micro-grid via a microsphere lithography strategy, which showed higher photocatalytic activity than the pure TiO2.film. The improvement of photocatalytic activity of Cu micro-grid to the TiO2.film is due to the charge carrier separation and electron transfer by the conducting metal grid. The photocatalytic activity was improved as metal loading increased, which obtained the best performance at a certain loading amount, and then decreased at higher loading amount. This phenomenon was attributed to the metal’s bulk effect which could be explained by the relationship between the energetic positions and the metal cluster size.

关键词： surface modification photocatalysis PS microspheres micro-grid

Effect of external and internal phosphate status on arsenic toxicity and accumulation in rice seedlings

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Journal of Environmental Sciences 2009年第3期21卷 346-351页

作者： WANG Lihong,DUAN Guilan Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,beijing 100085,china [a]Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Phosphorus （P） deficiency is thought to exacerbate the arsenic （As） phytotoxicity in paddy rice. The experiments were conducted to investigate the effects of external phosphate supply on As accumulation in rice and its toxicity under phosphate deficiency conditions. Rice seedlings pretreated with a phosphorus deficient nutrient solution （-P） for 14 d accumulated more As than those pretreated with a normal phosphorus supply nutrient solution （＋P）. Rice protreated with -P showed As toxicity symptoms after being exposed to 50 μmol/L arsenate for 4 h, while ＋P rice did not show any toxicity symptoms. Arsenic toxicity symptoms can be alleviated by increasing external P concentrations. The arsenate uptake rate and accumulation corresponded with the As toxicity in rice plants. Arsenic concentrations in rice roots decreased with increasing external phosphate concentrations. The lowest As accumulation and the highest P accumulation were found when the external P concentration reached 100μmol/L. In short, P deficiency increased the sensitivity of rice to arsenate and increasing of external phosphate supply could alleviate As toxicity.

关键词： phosphorus arsenate arsenic toxicity arsenic accumulation rice seedlings

VCO clock synchronization loop combined with dispersion equalization in optical coherent receivers

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The Journal of china Universities of Posts and Telecommunications 2010年第5期17卷 122-128页

作者： FAN Yang-yang,CHEN Xue,ZHOU Xian,ZHOU Wei-qin,ZHU Hai,LI Zhi-yu Key Laboratory of Information Photonics and Optical Communications,Ministry of Education,beijing university of Posts and Telecommunications,beijing 100876,china [a] Key Laboratory of Information Photonics Optical Communications Ministry of Education Beijing University of Posts Telecommunications Beijing 100876 China

In optical coherent receivers,the timing error detector （TED） in synchronization loop can not work normally when signal is distorted by large *** paper proposes a novel clock synchronization scheme which adds a butterfly-structured adaptive equalizer to the loop to fulfill synchronizations,equalizations and polarization de-multiplexing of two polarization states simultaneously under the control of single voltage-controlled oscillator （VCO）.Simulink simulation demonstrates the rationality and the feasibility of the combined loop with single VCO.

关键词： optical coherent receiver synchronization dispersion equalization

职教培养模式转变的路径及推进策略——基于“校企合作的工学结合”的分析

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教育发展研究 2008年第21期28卷 11-15页

作者：张宇和震北京师范大学教育学院北京100875

我国职业教育人才培养模式应当以"校企合作的工学结合"作为完整的改革目标。需要说明的是,促进"校企合作"与推动"工学结合"并非同义反复,而是代表了改革必经的两个阶段。前者重点在于整合校、企双方的教学资源,后者重点在于整合课堂与... 详细信息

我国职业教育人才培养模式应当以"校企合作的工学结合"作为完整的改革目标。需要说明的是,促进"校企合作"与推动"工学结合"并非同义反复,而是代表了改革必经的两个阶段。前者重点在于整合校、企双方的教学资源,后者重点在于整合课堂与工作两种学习情境,同时在具体实施中,不同阶段应分别采取相应的策略。

关键词：合作教育工学结合校企合作人才培养模式职业教育

Orthogonal linear polarized lasers (Ⅲ)——Applications in self-sensing

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Progress in Natural Science:Materials International 2005年第11期15卷 961-971页

作者： ZHANG Shulian, DU Wenhua and LIU Gang (The State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instruments, Tsinghua university, beijing 100084,{2.) The State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision Instruments Tsinghua University Beijing 100084 China

In this paper, the applications of orthogonal linear polarized lasers in self-sensing are reviewed. The properties for such a laser include the production of a new frequency in one longitudinal mode spacing, the tuning of frequency difference, the change of polarization states as cavity tuning, the control of mode competition intensity, the optical feedback, and so on. The orthogonal polarized lasers have been used as a laser nanometer ruler based on competition between two polarized lights in a HeNe laser and as a displacement measurement tool based on the optical feedback in the orthogonal polarized lasers. They are also used in the phase retardation measurement of a waveplate, the angle measurement, the vibration measurement, the pressure/force measurement, the weak magnetic field measurement, and so on. The structures of these new devices are simple and compact with the great advantages of high resolution and high accuracy. Some of these devices can trace to the source of the laser wavelength. The nanometer laser ruler is an example whose measurement range is 12.mm, resolution is 79 nm and linearity is less than 5×10-5. The repeatability of the phase retardation measuring system of waveplate can reach 3’.

关键词： orthogonal polarized laser frequency splitting optical feedback vibration measurement displacement measurement waveplate measurement angle measurement.

Synthesis and Crystal Structure of a Two-dimensional Polymeric Holmium Complex〔Ho(H_(2.saln)_(1.5)(NO_(3))_(3)〕

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Chinese Journal of Structural Chemistry 1999年第2期18卷 66-69页

作者： ZHANG Min KONG Fan Rong (Department of Chemistry, Capital normal university, {2. 100037)

The title polymeric complex Ho(H 2.aln) 1.5 (NO 3) 3 (H 2.aln= N,N’ bissalicyclidene ethylenediamine) C 2. H 2. N 6O 12. Ho was prepared and its crystal was characterized by X ray diffraction. The ligand is dischiff base from salicylaldehyde and ethylenediamine. The complex crystallizes in trigonal system, space group P3c1 (No. 165), M r=753.42. a=15.818(2., c=16.978(3) , V=3681(2.  3, D x =1.360 g/cm 3, Z=4, μ =2.2.86 mm -1 , F(000)=1492. R=0.049, R w =0.061. In the complex the coordination number of Ho(Ⅲ) is 9 with the geometry of a tricapped trigonal prism. All of the coordination atoms are oxygen atoms. The Ho(Ⅲ) ions are bridged by the dischiff base to form an infinite two dimensional polymeric network, parellel to the (001) plane.

关键词： holmium complex dischiff base N N’ disalicyclideneethylenediamine crystal structure