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Chinese Journal of Polymer Science 2008年第1期26卷 105-110页

作者： Lei, Hao Yu, Hai-yin lu, Ying lu, xiao-long Xu, Zhi-kang Zhejiang Univ Minist Educ Inst Polymer Sci Hangzhou 310027 Peoples R China Zhejiang Univ Minist Educ Key Lab Macromol Synth & Functionalizat Hangzhou 310027 Peoples R China Tianjin Polytech Univ Inst Membrane Sci & Technol Ningbo 315211 Peoples R China

A novel approach for the surface modification of poly(vinylidene fluoride)(PVDF)membrane was successfully realized through alkaline treatment,UV-induced bromine addition,and followed by surface-initiated atom transfer radical polymerization(ATRP)of methyl methacrylate(MMA).Chemical changes on the PVDF membrane before and after modification were analyzed with attenuated total reflectance Fourier transform infrared spectroscopy(ATR/FT-IR)and X-ray photoelectron spectroscopy(XPS).Primary kinetic study revealed...

关键词： Poly(vinylidene fluoride) Alkaline treatment Bromine addition Atom transfer radical polymerization

Study on the multiple characteristics of M3 generation of pea mutants obtained by neutron irradiation

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Nuclear Science and Techniques 2020年第7期31卷 46-54页

作者： Da-Peng Xu Ze-En Yao Jian-Bin Pan Hu-Yuan Feng Zhi-Qi Guo xiao-long lu School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China School of Life Sciences Lanzhou UniversityLanzhou 730000China Engineering Research Center for Neutron Application Technology Ministry of EducationLanzhou UniversityLanzhou 730000China

Irradiation breeding is an important technique in the effort to solve food shortages and improve the quality of agricultural *** this study,a field test was implemented on the M3 generation of two mutant pea plants gained from previous neutron radiation of pea *** relationship between agronomic characteristics and yields of the mutants was ***,differences in physiological and biochemical properties and seed nutrients were *** results demonstrated that the plant height,effective pods per plant,and yield per plant of mutant Leaf-M1 were 45.0%,43.2%,and 50.9%higher than those of the control group,*** analysis attributed the increase in yield per plant to the increased branching *** yield per plant of mutant Leaf-M2 was 7.8%higher than that of the control group,which could be related to the increased chlorophyll content in the *** was a significant difference between the two mutants in the increase in yield per plant owing to morphological variation between the two *** were significant differences in SOD activity and MDA content between the two mutants and the control,indicating that the physiological regulation of the two mutants also *** addition,the iron element content of seeds of the two mutants was about 10.9%lower than in the seeds of the control group,a significant *** findings indicate that the mutants Leaf-M1 and Leaf-M2 have breeding value and material value for molecular biological studies.

关键词： breeding attributed gained

Transport characteristics of space charge-dominated multi-species deuterium beam in electrostatic low-energy beam line

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Nuclear Science and Techniques 2018年第4期29卷 57-65页

作者： xiao-long lu Yu Zhang Jun-Run Wang Zhi-Wu Huang Zhan-Wen Ma Yao Yang Ze-En Yao School of Nuclear Science and Technology Lanzhou University Engineering Research Center for Neutron Application Ministry of Education Lanzhou University Institute of Modern Physics Chinese Academy of Sciences

The transport characteristics of a space chargedominated multi-species deuterium beam consisting of D_1^+,D_2^+, and D_3^+ particles in an electrostatic low-energy beam line are studied. First, the envelope equations of the primary D_1^+ beam are derived considering the space charge effects caused by all particles. Second, the evolution of the envelope of the multi-species deuterium beam is simulated using the PIC code TRACK, with the results showing a significant effect of the unwanted beam on the transport of the primary beam. Finally, different injected beam parameters are used to study beam matching, and a new beam extraction system for the existing duoplasmatron source is designed to obtain the ideal injected beam parameters that allow a D_1^+ beam of up to 50 m A to pass unobstructed through the electrostatic low-energy beam transport line in the presence of an unwanted(D_2^+, D_3^+)beam of 20 m A; at the same time, distortions of the beam emittance and particle distributions are observed.

关键词： Envelope equation Space charge effects Multi-species beam Electrostatic LEBT

Study on secondary electron suppression in compact D–D neutron generator

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Nuclear Science and Techniques 2019年第5期30卷 139-145页

作者： Zhi-Wu Huang xiao-Hou Bai Chang-Qi Liu Jun-Run Wang Zhan-Wen Ma xiao-long lu Zheng Wei Zi-Min Zhang Yu Zhang Ze-En Yao School of Nuclear Science and Technology Lanzhou University Engineering Research Center for Neutron Application Technology Ministry of EducationLanzhou University Institute of Modern Physics Chinese Academy of Sciences

A compact D–D neutron generator, with a peak neutron yield of D–D reactions up to 2.48×10~8 n/s is being developed at Lanzhou University in China for application in real-time neutron activation analysis. During tests, the problem of back acceleration of secondary electrons liberated from the neutron production target by deuterium ions bombardment was encountered. In this study,an electric field method and a magnetic field method for suppressing secondary electrons are designed and experimentally investigated. The experimental results show that the electric field method is superior to the magnetic field method. Effective suppression of the secondary electrons can be achieved via electrostatic suppression when the bias voltage between the target and the extraction-accelerating electrode is >204 V. Furthermore, the secondary electron emission coefficient for the mixed deuterium ion(D_1^+,D_2^+, and D_3^+) impacting on molybdenum is estimated. In the deuterium energy range of 80–120 keV, the estimated secondary electron emission coefficients are approximately 5–5.5 for the mixed deuterium ion glancing incidence of 45° and approximately 3.5–3.9 for the mixed deuterium ion normal incidence.

关键词： D–D neutron generator Secondary electron suppression Secondary electron emission coefficient

Contribution of Baroreflex Afferent Pathway to NPY-Mediated Regulation of Blood Pressure in Rats

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Neuroscience Bulletin 2020年第4期36卷 396-406页

作者： Yang Liu Shu-Yang Zhao Yan Feng Jie Sun xiao-long lu Qiu-Xin Yan Ying Li Zhuo Liu lu-Qi Wang Xun Sun Shijun Li Guo-Fen Qiao Bai-Yan Li Department of Pharmacology State-Province Key Laboratories of Biomedicine-Pharmaceutics of ChinaKey Laboratory of Cardiovascular Medicine ResearchMinistry of EducationCollege of PharmacyHarbin Medical UniversityHarbin 150081China Department of Clinical Laboratory The First Affiliated Hospital of Dalian Medical UniversityDalian 116011China Department of Pharmacology College of PharmacyDalian Medical UniversityDalian 116044China Riley Heart Center Wells Center for Pediatric ResearchIndiana University School of MedicineIndianapolisIN 46202USA

Neuropeptide Y (NPY), a metabolism-related cardiovascular factor, plays a crucial role in blood pressure(BP) regulation via peripheral and central pathways. The expression of NPY receptors (Y1R/Y2R) specific to baroreflex afferents impacts on the sexually dimorphic neural control of circulation. This study was designed to investigate the expression profiles of NPY receptors in the nodose ganglion (NG) and nucleus tractus solitary (NTS) under hypertensive conditions. To this end, rats with hypertension induced by NG-nitro-L-arginine methylester (L-NAME) or high fructose drinking (HFD), and spontaneously hypertensive rats (SHRs) were used to explore the effects/mechanisms of NPY on BP using functional, molecular, and electrophysiological approaches. The data showed that BP was elevated along with baroreceptor sensitivity dysfunction in model rats;Y1R was up-or down-regulated in the NG or NTS of male and female HFD/L-NAME groups,while Y2R was only down-regulated in the HFD groups as well as in the NG of the male L-NAME group. In SHRs,Y1R and Y2R were both down-regulated in the NTS, and not in the NG. In addition to NPY-mediated energy homeostasis, leptin-melanocortin activation may be essential for metabolic disturbance-related hypertension. We found that leptin and a-melanocyte stimulating hormone (aMSH) receptors were aberrantly down-regulated in HFD rats. In addition, a-MSH concentrations were reduced and NPY concentrations were elevated in the serum and NTS at 60 and 90 min after acute leptin infusion. Electrophysiological recordings showed that the decay time-constant and area under the curve of excitatory post-synaptic currents were decreased by Y1R activation in A-types, whereas, both were increased by Y2R activation in Ah-or C-types. These results demonstrate that sex-and afferent-specific NPY receptor expression in the baroreflex afferent pathway is likely to be a novel target for the clinical management of metabolism-related and essential hypertension.

关键词： Neuropeptide Y Hypertension Nucleus of the solitary tract Excitatory post-synaptic current Baroreflex

Inherited Genetic Susceptibility to Nonimmunosuppressed Epstein-Barr Virus-associated T/NK-cell Lymphoproliferative Diseases in Chinese Patients

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Current Medical Science 2021年第3期41卷 482-490页

作者： Yu-qi GUAN Ke-feng SHEN Li YANG Hao-dong CAI Mei-lan ZHANG Jia-chen WANG xiao-lu long Jie XIONG Jia GU Pei-ling ZHANG Min xiao Wei ZHANG Jian-feng ZHOU Department of Hematology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Epstein-Barr virus(EBV)T/NK-cell lymphoproliferative diseases are characterized by clonal expansion of EBV-infected T or NK cells,including chronic active EBV infection of T/NK-cell type(CAEBVT/NK),EBV-associated hemophagocytic lymphohistiocytosis(EBV HLH),extranodal NK/T-cell lymphoma of nasal type(ENKTL),and aggressive NK-cell leukemia(ANKL).However,the role of inherited genetic variants to EBV+T/NK-LPDs susceptibility is still unknown.A total of 171 nonimmunosuppressed patients with EBV T/NK-LPDs and 104 healthy donors were retrospectively collected and a targeted sequencing study covering 15 genes associated with lymphocyte cytotoxicity was *** 94 gene variants,mostly located in UNCI 3D,LYST,ITK,and PRF1 genes were detected,and mutations covered 28/50(56.00%)of CAEBV-T/NK,31/51(60.78%)of EBV HLH,13/28(46.42%)of ENKTL,and 13/48(27.09%)of *** mutations represented monoallelic and ***-year overall survival rate of patients with CAEBV-T/NK and EBV+HLH was significantly lower in patients with germline mutations than in those without germline mutations(P=0.0284,P=0.0137).Our study provided novel insights into understanding a spectrum of nonimmunosuppressed EBV*T/NK-LPDs with respect to genetic defects associated with lymphocyte cytotoxicity and reminded us that the gene sequencing may be an auxiliary test for diagnosis and risk stratification of EBV+T/NK-LPDs.

关键词： germline mutation EBV-associated T/NK-cell lymphoproliferative disease hemophagocytic lymphohistiocytosis primary immunodeficiencies lymphocyte cytotoxicity gene sequencing

中国利率与汇率联动机制的制约因素和路径选择研究

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特区经济 2007年第5期 60-62页

作者：禄晓龙云南大学经济学院云南昆明650091

在经济全球化的今天,金融及货币政策的全球化趋势也日渐明显,利率和汇率之间国际和国内联动效应非常明显。结合中国实际经济运行状况,剖析我国利率和汇率联动的约束因素,指出我国利率与汇率联动机制的路径选择,将对中国经济乃至世界经... 详细信息

在经济全球化的今天,金融及货币政策的全球化趋势也日渐明显,利率和汇率之间国际和国内联动效应非常明显。结合中国实际经济运行状况,剖析我国利率和汇率联动的约束因素,指出我国利率与汇率联动机制的路径选择,将对中国经济乃至世界经济都有重要意义。

关键词：利率汇率联动机制制约因素路径选择

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超声电机定子热机电耦合特性

振动工程学报 2011年第5期24卷 522-528页

作者：芦小龙赵淳生南京航空航天大学精密驱动研究所江苏南京210016

应用于极端环境的超声电机会受到温度场、应力场和电场的共同作用,定子在热机电耦合激励下的响应与电机工作特性密切相关。以行波型旋转超声电机为对象建立定子的能量泛函,采用假设模态的方法得到了热机电耦合动力学模型。运用有限元方... 详细信息

应用于极端环境的超声电机会受到温度场、应力场和电场的共同作用,定子在热机电耦合激励下的响应与电机工作特性密切相关。以行波型旋转超声电机为对象建立定子的能量泛函,采用假设模态的方法得到了热机电耦合动力学模型。运用有限元方法对热机电耦合作用下的定子进行仿真,分析了与理论计算结果的差异。建立了定子热扫频试验平台和热变形试验平台,测定温度对定子稳态形变、模态频率和振幅的影响,对理论模型的分析方法进行了评价。理论分析和试验结果揭示了超声电机定子在热机电耦合作用下的振动行为的变化规律,为下一步极端环境超声电机的设计和优化提供了依据。

关键词：超声电机定子热机电耦合热扫频热变形

A NOVEL HIGH-SPEED ROTARY ULTRASONIC MOTOR APPLIED TO MICRO AIR VEHICLE

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A NOVEL HIGH-SPEED ROTARY ULTRASONIC MOTOR APPLIED TO MICRO ...

A SOLAR PANEL CLEANING SYSTEM BASED ON A LINEAR PIEZOELECTRIC ACTUATOR

2016年全国压电和声波理论及器件应用研讨会

作者： Le WANG xiao-long lu Chun-sheng ZHAO State Key Lab of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics School of Mathematics and Statistics Qiannan Normal University for Nationalities

Background, Motivation and Objective Ultrasonic motors(USMs) utilize the elastic body’s(stator) vibration induced by piezoelectric materials with the converse piezo effect and the friction force to output mechanical movements. Ultrasonic motors own many benefits such as self-braking, quick response, quite operation, compact size and no electromagnetic interference. Due to these advantages, ultrasonic motors have been used widely in many different fields, such as nano/micro positioning stage, optical systems and biomedical instruments etc. In traditional micro air vehicles(MAVs) or mini UAVs, electromagnetic motors are widely used but extremely easy to be disturbed by the external magnetic circumstance. And power consumption is another issue needed to be considered. Comparatively, ultrasonic motors can overcome these problems and thus have great potentials in UAVs or UAVs. Statement of Contribution/Methods In this paper, a novel ultrasonic motor based on the out-of plane flexural vibration mode is designed, fabricated and characterized. A numerical simulation of the proposed ultrasonic motor is carried out by ANSYS. The trajectories of the contact point can be described from the calculated results and the optimal height of the solid shaft is obtained. Experimental results agree well with those of theoretical analyses. Results A prototype of the proposed motor is fabricated and characterized. The vibration amplitude of the stator’s metal disk is measured by the PSV laser Doppler vibrometer. The prototype’s rotational speed can reach 5000 r/min and the amplitude of the disk can reach 0.3μm when the driven frequency is 20.582 k Hz and the driven voltage is 300 Vp-p. Discussion and Conclusions A novel milli size rotational ultrasonic motor is proposed. The working principle is verified by the FEM analyses. The prototype of the motor is manufactured and its output characteristics are measured. It can be seen that proposed ultrasonic motor has a good working performance at

关键词： Ultrasonic motor Out-of-plane flexural vibration mode Traveling wave MAV UAV

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A SOLAR PANEL CLEANING SYSTEM BASED ON A LINEAR PIEZOELECTRI...