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Decomposing Triples of Z_(p^n) and Z_(3p^n) into Cyclic Designs

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Acta Mathematica Sinica,English Series 2013年第11期29卷 2111-2128页

作者： zi Hong TIAN Rui zhong WEI College of Mathematics and Information Science Hebei Normal University Department of Computer Science Lakehead University

In this paper, we give some decompositions of triples of Zp^n or Z3p^n into cyclic triple systems. New constructions of difference families are given. Some infinite classes of simple cyclic triple systems are obtained... 详细信息

关键词： Decomposition cyclic designs triple systems simple designs difference families

The Rearrangement of 2-Benzothiazolylthioacetyl Hydrazide in Synthesis of s-Triazolo[3,4-b]benzothiazole-3-thiol

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Chinese Chemical Letters 2002年第4期13卷 287-289页

作者： Yan ZHANG Ren zhong QIAO Chao Feng DAI Peng Fei XU zi yi ZHANG National Laboratory of Applied Organic Chemistry Department of ChemistryLanzhou UniversityLanzhou 730000

The rearrangement reaction of 2-benzothiazolylthioacetyl hydrazide 1 with potassium hydroxide and carbon disulfide in ethanol to produce s-triazolo[3, 4-b]benzothiazole-3-thiol 3 was described. 3 also can be obtained from 2-benzothiazolylhydazine 2 and the two methods for getting 3 were compared. Mannich reaction of compounds 3 was reported too.

关键词： Rearrangement s-triazolo[3, 4-b]benzothiazole-3-thiol Mannich reaction.

Changes in lumbosacral spinal nerve roots on diffusion tensor imaging in spinal stenosis

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Neural Regeneration Research 2015年第11期10卷 1860-1864页

作者： zhong-jun Hou Yong Huang zi-wen Fan Xin-chun Li Bing-yi Cao Department of Radiology the Second Affiliated Hospital of Guangzhou Medical University Department of Orthopedics the Second Affiliated Hospital of Guangzhou Medical University Department of Radiology the First Affiliated Hospital of Guangzhou Medical University

Lumbosacral degenerative disc disease is a common cause of lower back and leg pain. Conventional T1-weighted imaging（T1WI） and T2-weighted imaging（T2WI） scans are commonly used to image spinal cord degeneration. However, these modalities are unable to image the entire lumbosacral spinal nerve roots. Thus, in the present study, we assessed the potential of diffusion tensor imaging（DTI） for quantitative assessment of compressed lumbosacral spinal nerve roots. Subjects were 20 young healthy volunteers and 31 patients with lumbosacral stenosis. T2 WI showed that the residual dural sac area was less than two-thirds that of the corresponding normal area in patients from L3 to S1 stenosis. On T1 WI and T2 WI, 74 lumbosacral spinal nerve roots from 31 patients showed compression changes. DTI showed thinning and distortion in 36 lumbosacral spinal nerve roots（49%） and abruption in 17 lumbosacral spinal nerve roots（23%）. Moreover, fractional anisotropy values were reduced in the lumbosacral spinal nerve roots of patients with lumbosacral stenosis. These findings suggest that DTI can objectively and quantitatively evaluate the severity of lumbosacral spinal nerve root compression.

关键词： nerve regeneration magnetic resonance imaging diffusion tensor imaging lumbosacralarea degeneration nerve root fractional anisotropy neural regeneration

Development of a portable multi-channel system for plant physiological signal recording

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Information Processing in Agriculture 2016年第2期3卷 124-132页

作者： Ting Li zi-Yang Wang Dong-Jie Zhao Lan Huang zhong-yi Wang College of Information and Electrical Engineering China Agricultural UniversityBeijing 100083China Modern Precision Agriculture System Integration Research Key Laboratory of Ministry of Education Beijing 100083China Key Laboratory of Agricultural Information Acquisition Technology(Beijing) Ministry of AgricultureBeijing 100083China

Bioelectrical signals can reflect physiological state of organs or tissues in plants and have a significant potential value in research of plant stress *** order to study the relationship between environment factors and electrical signals in plant,a portable multichannel physiological signal acquisition system which relevant in plant physiology research was *** parameters and electrical signals can be measured in different channels by the acquisition system simultaneously and the measurement data will be displayed in an embedded integrated touch screen which is the system processing *** system was validated to be stable and reliable after the calibration and repeated experiments of recording electrical signals in Helianthus annuus L.

关键词： Bioelectrical signals Acquisition system Multi-channel Portable device

Research on new software compensation method of static and quasi-static errors for precision motion controller

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第12期8卷 1938-1943页

作者： REN Kun FU Jian-zhong CHEN zi-chen Department of Mechanical Engineering Zhejiang University Hangzhou 310027 China

To reduce mechanical vibrations induced by big errors compensation, a new software compensation method based on an improved digital differential analyzer (DDA) interpolator for static and quasi-static errors of machine tools is proposed. Based on principle of traditional DDA interpolator, a DDA interpolator is divided into command generator and command analyzer. There are three types of errors, considering the difference of positions between compensation points and interpolation segments. According to the classification, errors are distributed evenly in data processing and compensated to certain interpolation segments in machining. On-line implementation results show that the proposed approach greatly improves positioning accuracy of computer numerical control (CNC) machine tools.

关键词： Static and quasi-static errors Positioning and machining accuracy Digital differential analyzer (DDA) interoolator

Experiment on the Nonlinear Phenomena in an Electron Cyclotron Resonance Plasma

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Chinese Physics Letters 1996年第12期13卷 916-918页

作者： YAO Xin-zi JIANG De-yi Institute of Physics Chinese Academy of SciencesBeijing 100080

Two hysteresis loops and tristable states in an electron cyclotron resonance plasma system have been observed and oscillatory waveforms and their power spectra in different stable state are described in this *** the microwave power was increased,the oscillation with original fundamental frequency gradually transferred to harmonic frequencies and then sudden jumped to a regular oscillation with single fourth harmonic frequency.

关键词： harmonic oscillation Electron

An experimental setup with controllable tuning parameters for studying the Kondo systems

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Science China(Physics,Mechanics & Astronomy) 2022年第4期65卷 121-122页

作者： zhong-yi Lu Department of Physics Renmin University of ChinaBeijing 100872China

The Kondo physics has been studied since the 1960 s in condensed matter physics[1,2],which is mainly determined by two competing factors namely the Kondo effect and the Ruderman-Kittel-Kasuya-Yosida(RKKY)interaction.

关键词： interaction Kondo condensed

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A survey on intelligence approaches that may be useful for information and communication technology research

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The Journal of China Universities of Posts and Telecommunications 2008年第1期15卷 1-5,17页

作者： zhong yi-xin School of Information Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

The concepts on information and communication technology （ICT） and ＂intelligence＂ are defined firstly and the analyses on the environment and requirements for ICT are then followed. Based on the definitions and the analyses, a survey on intelligence approaches that may be useful for ICT is thus made. The conclusion drawn from the survey is a recommendation by saying that intelligence approaches have been one of the keys for further development of the entirety of ICT and therefore should receive much more attentions from ICT researchers in the years to come.

关键词： uncertainty complexity intelligence approaches,ICT

Enhancing self-assembly efficiency of macrocyclic compound into nanotubes by introducing double peptide linkages

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Chinese Chemical Letters 2024年第11期35卷 299-303页

作者： Cheng-Yan Wu yi-Nan Gao zi-Han Zhang Rui Liu Quan Tang zhong-Lin Lu College of Chemistry Beijing Normal UniversityBeijing 100875China College of Chemistry and Materials Engineering Bohai UniversityJinzhou 121013China

Constructing more stable self-assembled organic nanotubes has been one of the focuses of scientists in recent ***(m-phenylene ethynylene)(m-PE)benzene macrocycles can form stable tubular self-assemblies in nonpolar or weakly polar solvents through theπ-πinteraction of the main skeleton and the hydrogen bonding of the side chain *** covalently linked two macrocyclic units at the para position of the macrocycles using two oligo(β-alanine)linkers through an efficient synthetic ***-visible spectroscopy,fluorescence spectroscopy,and circular dichroism spectroscopy were employed to demonstrate that the incorporation of two peptide chains significantly enhances the stability of the ***,the average open time of the ion channel formed by the macrocyclic dimer in the lipid bilayer was significantly better than that of the ion channel formed by a single *** study shows that this strategy effectively improves the efficiency of self-assembly and the stability of its formed self-assemblies,providing a feasible strategy for constructing organic self-assembled nanotubes in highly polar solvents.

关键词： Macrocyclic compounds Supramolecular assembly Ion transportation Synthetic ion channels Molecular nanotubes