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CSEE Journal of Power and Energy Systems 2018年第1期4卷 39-48页

作者： Hao Tian Xiaohan Wen yun wei li Department of Electrical and Computer Engineering University of AlbertaEdmontonABT6G 2V4Canada China Mobile Group liaoning Co. Ltd.ShenyangChina

In recent years,the hybrid AC-DC microgrid has been well accepted as it combines the advantages of both AC and DC *** the microgrid contains both DC sub-grids and AC sub-grids,interlinking DC-AC converters are ***,considering the nonlinear AC loads may deteriorate the voltage quality of the AC bus,embedding an ancillary harmonic compensation function to the interlinking converters is ***,the conventional harmonic control methods used for active power filters(APFs)may not be suitable for the interlinking converters due to the main purpose of it is to exchange real and reactive power between the DC and AC *** switching frequency is preferred to be lower than the APFs when the capacity of the microgrid is *** low switching frequency,harmonic compensation performance or even the system stability may be *** this paper,a harmonic compensation approach suitable for hybrid AC-DC interlinking converters at low switching frequency is *** feeding the PWM reference signal with the harmonic compensation component directly to avoid the multi-loop control path of the fundamental component,the proposed method can achieve the effective harmonics compensation without being limited by the closed-loop control *** proposed method,modeling approaches,stability analysis,as well as detailed virtual impedance design are *** verification is also provided.

关键词： Harmonic compensation hybrid AC-DC microgrid virtual impedance

Removal of adhesive dusts from flue gas using corona discharges with spraying water

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Journal of Environmental Sciences 2003年第4期15卷 554-561页

作者： XU De\|xuan, ZHAO Jian\|wei, DING yun\|zheng, GE wei\|li (Department of Environmental Science and Engineering, Northeast Normal University, Changchun 130024, China. Department of Knviranmental Science and Engineering Northeast Normal University Changchun 130024

Effective removal of adhesive and fine dusts from flue gas is very difficult. A new method of electrostatic precipitation of the corona discharges with spraying water(CDSW) was introduced. A new electrode configuration and the circulation spraying of water were employed in the method. The efficient electrostatic precipitation for adhesive and fine dusts can be accomplished without any drain water during a long operating period. The fundamental structure, discharge characteristics, mechanism of spraying and precipitation principle of the electrostatic precipitation using CDSW were described and analyzed. The V I characteristics, spraying state, supplying water quantity, influence of temperature and clean of the electrodes were researched in series experiments. The treating effects of circulating spraying using the corona plasma at the same time of electrostatic precipitation were investigated. The fundamental theories and experimental data were proposed, in order to effectively remove the adhesive dusts from flue gas using CDSW in practice.

关键词： aerosol with adhesive dusts corona discharges with spraying water electrostatic precipitation

Asymmetric synthesis of L-carnitine from (R)-3-chloro-1,2-propanediol

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Chinese Chemical Letters 2011年第7期22卷 765-767页

作者： Xu Qin li yun Xu Yang wei li Wang Bin Hu Hui Min Xue Tian Yi Zhang Xue Tao Zhang Department of Chemistry University of Science and Technology Beijing Beijing 100083 China

A practical chemical synthesis of L-camitine （1） has been accomplished from （R）-3-chloro-1,2-propanediol （（R）-4）, which is a main by-product originated from （R,R）-Salen Co（III） catalyzed hydrolytic kinetic resolution （HKR） of （±）-epichlorohydrin. （R）-4 was utilized as a chiral starting material to prepare the key intermediate cyclic sulfite （（R）-S）. The new synthetic approach demonstrated an efficient utilization of organic by-product for the asymmetric synthesis of bioactive compounds.

关键词： L-Camitine Cyclic sulfite (R)-3-Chloro-1,2-propanediol

Flow control characteristics of the digital and mechanical redundancy control electric modulation valve

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第8期23卷 599-609页

作者： He liU Bin ZHAO Bo WANG Long QUAN yun-xiao HAO yun-wei li Key Laboratory of Advanced Transducers and Intlligent Control System of Ministry of Education and Shanxi Province Taiyuan University of TechnologyTaiyuan 030024China Deparment of Electrical and Computer Engineering University of AlbertaEdmonton ABT6G1H9Canada

The electrical modulation valve can provide proportional output valve element displacement,flow,or pressure according to a continuously changing input electrical *** is the core component of electro-hydraulic proportional control *** remove the influence of pressure difference changes on the output flow,the traditional scheme is to use a pressure compensation valve,which increases the difficulty of both manufacturing and maintaining the *** solve this problem,a method of digital and mechanical redundancy control flow is *** sensors are installed at the inlet and outlet of the valve,and the controller adjusts the displacement of the valve element according to the pressure difference between the valve ports to realize high-precision control of the flow.A pressure compensation valve is installed in front of the valve,and a three-way solenoid valve is used to control the working of the compensation *** the case of sensor failure,the valve is switched to the mechanical compensation differential pressure mode,to control the flow and to achieve redundancy *** system security is thereby *** feasibility of this scheme is verified through simulation and *** results show that,both for digital compensation and mechanical compensation,the output flow can be kept constant when the pressure difference changes,and the system has good static and dynamic *** principle can be applied to the displacement-flow feedback type electrical modulation valve,and can realize accurate control of the flow of the pilot valve and,finally,accurate control of the flow in the main valve.

关键词： Electrical modulation valve Control characteristics Co-simulation Redundancy control

Overexpression of brain-derived neurotrophic factor in the hippocampus protects against post-stroke depression

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Neural Regeneration Research 2015年第9期10卷 1427-1432页

作者： Hao-hao Chen Ning Zhang wei-yun li Ma-rong Fang Hui Zhang Yuan-shu Fang Ming-xing Ding Xiao-yan Fu Medical Molecular Biology Laboratory School of Medicine Jinhua Polytechnic Institute of Neuroscience School of Medicine Zhejiang University Center of Experimental Animals Jinhua Food and Drug Administration

Post-stroke depression is associated with reduced expression of brain-derived neurotrophic factor （BDNF）. In this study, we evaluated whether BDNF overexpression affects depression-like behavior in a rat model of post-stroke depression. The middle cerebral artery was occluded to produce a model of focal cerebral ischemia. These rats were then subjected to isolation-housing combined with chronic unpredictable mild stress to generate a model of post-stroke depression. A BDNF gene lentiviral vector was injected into the hippocampus. At 7 days after injection, western blot assay and real-time quantitative PCR revealed that BDNF expression in the hippo- campus was increased in depressive rats injected with BDNF lentivirus compared with depressive rats injected with control vector. Furthermore, sucrose solution consumption was higher, and horizontal and vertical movement scores were increased in the open field test in these rats as well. These findings suggest that BDNF overexpression in the hippocampus of post-stroke depressive rats alleviates depression-like behaviors.

关键词： nerve regeneration brain injury brain-derived neurotrophic factor lentivirus post-strokedepression depression-like behavior hippocampus cerebral ischemia sucrose solution consumption open field test chronic unpredictable mild stress western blot assay neural regeneration

Multilevel Current Source Converters for High Power Medium Voltage Applications

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CES Transactions on Electrical Machines and Systems 2017年第3期1卷 306-314页

作者： li Ding Yujuan lian yun wei li Department of Electrical and Computer Engineering University of AlbertaEdmontonABCanada 不详

In medium voltage high power applications,multi-level current source converters(CSCs)are good candidate to increase system power region,reliability,and the quality of output *** with widely researched voltage source multi-level converters(MLCs),the current source MLCs have the advantages of inherent short-circuit protection,high power capability and high quality of output current *** main features of MLCs include reduced harmonics,lower switching frequency and reduced current stress on each device which is a particularly important for high power application with low voltage and high current *** paper conducts a general review of the current research about MLCs in higher power medium voltage *** different types of parallel structure based MLCs and the modulation methodologies will be introduced and ***,the circuit analysis of the common-mode(CM)loop for parallel structures will be conducted,the common-mode voltage(CMV)and circulating current suppression methods developed on the base of multilevel modulations will be addressed.

关键词： Circulating current common-mode voltage current source converters multi-level converter high power medium voltage parallel structure

Effect of intracoronary administration of anisodamine on slow reflow phenomenon following primary percutaneous coronary intervention in patients with acute myocardial infarction

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Chinese Medical Journal 2007年第14期120卷 1226-1231页

作者： FU Xiang-hua FAN wei-ze GU Xin-shun wei Yong-yun JIANG yun-fa WU wei-li li Shi-qiang HAO Guo-zhen wei Qing-min XUE ling Department of Cardiology Second Hospital of Hebei Medical University Insistitute of Hebei Province of CardioCerebrovascular Disease Shijiazhuang 050000 China

Background Many basic and clinical studies have proved that anisodamine can produce significant effect on relieving microvascular spasm, improving and dredging the coronary microcirculation. It may be beneficial to the improvement of slow-reflow phenomenon （SRP） following percutaneous coronary intervention （PCI） for acute myocardial infarction （AMI）. So we investigated the effect of intracoronary administration of anisodamine on SRP of infarct related artery （IRA） following primary PCI in patients with ST segment elevated acute myocardial infarction （STEAMI）. Methods Twenty-one patients with SRP from a total of 148 STEAMI patients accepted primary PCI were enrolled into this study from September 2004 to December 2005. When SRP happened, nitroglycerin （200 μg） was ＂bolus＂ injected firstly into IRA to exclude the spasm of epicardial artery and identify SRP as well as a baseline and self-control agent following PCI. Ten minutes later, 1000 μg of anisodamine was injected into IRA with SRP at 200 μg/s, while the coronary angiography （CAG） was taken before and at 1st, 3rd and 10th minute after administration of nitroglycerin or anisodamine, respectively. The corrected TIMI frame count （cTFC）, TIMI myocardial perfusion grade （TMPG） and the diameter of IRA were calculated and analyzed by Gibson＇s TIMI frame count method using quantitative computer angiography （QCA） system to evaluate the influence of anisodamine on coronary flow and vessel lumen. In the meantime the invasive hemodynamic parameters of intracoronary and systemic artery （systolic, diastolic and mean pressure） and electrocardiogram （ECG） were measured and monitored. The changes of ventricular performance parameters and the adverse reaction were evaluated and followed-up at 1 month post-PCI. Results No significant changes in cTFCs and TMPGs were found at 1st, 3rd and 10th minute after intracoronary administration of nitroglycerin as compared with the baseline control （P〉0.05）. cTFCs were decreased by 58.3%,

关键词： myocardial infarction anisodamine percutaneous coronary intervention slow reflow phenomenon

Sex-dependent alterations in extracellular vesicles linking chronic spinal cord injury to brain neuroinflammation and neurodegeneration

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Neural Regeneration Research 2025年第2期20卷 483-484页

作者： yun li Junfang Wu Department of Anesthesiology&Shock Trauma and Anesthesiology Research(STAR)CenterUniversity of Maryland School of MedicineBaltimoreMDUSA

Traumatic spinal cord injury(SCI)is a devastating exogenous injury with long-lasting consequences and a leading cause of death and disability *** in assistive technology,rehabilitative interventions,and the ability to identify and intervene in secondary conditions have significantly increased the long-term survival rate of SCI patients,with some people even living well into their seventh or eighth *** survival changes have led neurotrauma researchers to examine how SCI interacts with brain *** health and epidemiological data showed that patients with long-term SCI can have a lower life expectancy and quality of life,along with a higher risk of comorbidities and complications.

关键词： alterations inflammation injury

Building Trust Peer-to-peer Networks with TLS and X.509 Certificates

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计算机工程 2002年第S1期28卷 125-128页

作者： li yun1,li wei-hua2,(Department of Computer Science and Engineering, Northwestern Polytechnic University, Xi’an 710072China, ly@***, liweihua@***) Department of Computer Science and Engineering Northwestern Polytechnic University Xi'an 710072 China lyhenu.edu. Cn liweihua@***

As soon as a P2P application grows to the point where it becomes interesting, the issues of trust and security appear on the horizon. The core of the paper is on how to build trustful peer-to-peer networks with TLS and X.509 certificates under JXTA architecture. The use of authentication, authorization, and encryption establishes trust in P2P applications. Without a foundation of trust, many types of interesting applications such as e-commerce won’t take hold on top of the P2P infrastructure.

关键词： Peer-to-peer networking TLS X.509 JXTA Trust Security

A Wind Tunnel Experimental Study on the Wake Characteristics of a Horizontal Axis Wind Turbine

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Journal of Thermal Science 2025年第1期34卷 145-158页

作者： GUO Xingduo li Yinran li Rennian MA Yulong wei Kui College of Energy and Power Engineering Lanzhou University of Technology Key Laboratory of Fluid Machinery and Systems Gansu Provincial Technology Centre for Wind Turbines

The characteristics of wind turbine wakes are influenced by multiple factors,including the atmospheric boundary layer(ABL) wind and wind turbine operating conditions(e.g.,tip speed ratio and yaw angle).In this study,two types of ABL winds with different velocity gradients and turbulence intensities are generated in a wind tunnel through configurations of spires,baffles,and various numbers of roughness elements.A wind turbine with a rotor diameter of 0.8 m and a hub height of 0.6 m is tested under varying tip speed ratios,yaw angles,and ABL wind *** results indicate that the streamwise velocity deficit in the near-wake region becomes more pronounced with an increase in the tip speed ratio,while the far-wake velocity deficit remains largely unaffected by changes in the tip speed *** the yaw angle increases,the wake deflection becomes more prominent and the wake narrows;the offset of the wake center at various downstream positions grows linearly,reaching a maximum value of approximately half the rotor ***,the turbulence level and influence range in the wake region are reduced when the turbine is *** ABL wind conditions,high turbulence intensity in the incoming flow accelerates wake recovery,and the Reynolds stress at different lateral positions tends to become consistent with increasing longitudinal ***,turbulence has a significant impact on the meandering characteristics of the wind turbine wake,with greater fluctuations in the wake center observed under higher turbulence ***,this study provides insights that could inform the optimal operation of wind farms.

关键词： horizontal axis wind turbine turbulence wind tunnel experiment wind turbine wake