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World Journal of Gastroenterology 2004年第18期10卷 2697-2700页

作者： Chuan-YongGuo Jian-YeWu yun-BinWu min-ZhangZhong Han-mingLu DepartmentofGastroenterology ShanghaiTenthPeopleHospitalofTongjiUniversityShanghai200072China DepartmentofGastroenterology XinhuaHospitalofShanghaiSecondMedicalUniversityShanghai200092China

AIM: To explore the effects of endothelin-1(ET-1) on hepatic stellate cells (HSCs) DNA uptake, DNA synthesis,collagen synthesis and secretion, inward whole-cell calcium concentration ([Ca^2+]i) as well as the blocking effect of verapamil on ET-l-stimulated release of inward calcium(Ca2+) of HSC in ***: Rat hepatic stellate cells (HSCs) were isolated and cultivated. ^3H-TdR and ^3H-proline incorporation used for testing DNA uptake and synthesis, collagen synthesis and secretion of HSCs cultured in vitro;, Fluorescent calcium indicator Fura-2/AM was used to measure [Ca^2+]i ***: ET-1 at the concentration of 5×10^-8 mol/L,caused significant increase both in HSC DNA synthesis (2 247+344 cpm, Pmin and then went down slowly to165+51 mol/L(Pmin from resting state (39±4 mol/L)after treated with ET-1. Verapamil (5 mol/L) blocked ET-1-activated [Ca^2+li inward HSCs compared with control group(Pmin. It could also raise [Ca^2+]i inward HSCs even without Ca^2+ in extracellular fluid, and had a remarkable dose-effect relationship(P<0.05). Meanwhile,verapamil could restrain the action of ET-1(P<0.05).CONCLUSION: Actions of ET-1 on collagen metabolism of HSCs may depend on the transportation of inward wholecell calcium.

关键词：内皮素-1 肝星状细胞分芽繁殖胶原质 ET-1 分泌物细胞内钙浓度 HSCs

Development of the detonation-driven expansion tube for orbital speed experiments

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Science China(Technological Sciences) 2015年第4期58卷 695-700页

作者： JIANG Zong Lin WU Bo GAO yun Liang ZHAO Wei HU Zong min State Key Laboratory of High-temperature Gas Dynamics Institute of Mechanics Chinese Academy of Sciences

The hypersonic flow at orbital speeds is a fundamental issue for the ground tests of aerospace *** detonation-driven high-enthalpy expansion tube(JF16 expansion tube)was developed to investigate re-entry physics.A forward detonation cavity(FDC)driver was applied in the JF16 expansion tube to create stable driving *** sound speed ratio of the detonated to test gas was examined to minimize the magnitude of test flow *** acceleration section length,incident shock decay and diaphragms thickness were investigated in detail to obtain optimal operation *** visualization was also carried out with schlieren system to demonstrate the test flow stability and the effective test *** data showed that the test flow with a velocity of 8.3 km/s and a total enthalpy up to 40 MJ/kg can be generated successfully and the test duration lasts for more than 50μs.

关键词： detonation driver shock-expansion tube high-enthalpy flow test flow

Synthesis of a kind of geminal imidazolium ionic liquid with long aliphatic chains

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Chinese Chemical Letters 2007年第1期18卷 48-50页

作者： yun Sheng Ding min Zha Jun Zhang Seng Shan Wang Department of Polymer Materials and Engineering School of Chemical Engineering Hefei University of Technology Hefei 230009 China CAS Key Laboratory of Engineering Plastics Joint Laboratory of Polymer Science and Materials Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

A novel geminal imidazolium ionic liquid with long hydrocarbon group, 1,4-bis （3-tetradecylimidazolium- 1-yl） butane bromide was synthesized and an efficient synthesized method was introduced detailedly. Its structu... 详细信息

关键词： Geminai imidazolium ionic liquid Long aliphatic chain Physicochemicai properties

Joint adaptive power allocation and interference suppression algorithms based on the MSER criterion for wireless sensor networks

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第10期15卷 917-928页

作者： Gui-jie WANG yun-long CAI min-jian ZHAO Jie ZHONG Department of Information Science and Electronic Engineering Zhejiang University

In this study, a two-hop wireless sensor network with multiple relay nodes is considered where the amplify-and-forward(AF) scheme is employed. Two algorithms are presented to jointly consider interference suppression and power allocation(PA) based on the minimization of the symbol error rate(SER) criterion. A stochastic gradient(SG) algorithm is developed on the basis of the minimum-SER(MSER) criterion to jointly update the parameter vectors that allocate the power levels among the relay sensors subject to a total power constraint and the linear receiver. In addition, a conjugate gradient(CG) algorithm is developed on the basis of the SER criterion. A centralized algorithm is designed at the fusion center. Destination nodes transmit the quantized information of the PA vector to the relay nodes through a limited-feedback channel. The complexity and convergence analysis of the proposed algorithms are carried out. Simulation results show that the proposed two adaptive algorithms significantly outperform the other previously reported algorithms.

关键词： Cooperative communications Adaptive filtering Symbol error rate(SER) Interference suppression Power allocation

Thermal and induced flow characteristics of radio frequency surface dielectric barrier discharge plasma actuation at atmospheric pressure

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Chinese Physics B 2017年第1期26卷 320-325页

作者： Wei-long Wang Jun Li Hui-min Song Di Jin min Jia yun Wu Science and Technology on Plasma Dynamics Laboratory Air Force Engineering University Xi＇an 710038 China

Thermal and induced flow velocity characteristics of radio frequency（RF） surface dielectric barrier discharge（SDBD）plasma actuation are experimentally investigated in this paper. The spatial and temporal distributions of the dielectric surface temperature are measured with the infrared thermography at atmospheric pressure. In the spanwise direction, the highest dielectric surface temperature is acquired at the center of the high voltage electrode, while it reduces gradually along the chordwise direction. The maximum temperature of the dielectric surface raises rapidly once discharge *** several seconds（typically 100 s）, the temperature reaches equilibrium among the actuator＇s surface, plasma, and surrounding air. The maximum dielectric surface temperature is higher than that powered by an AC power supply in dozens of k Hz. Influences of the duty cycle and the input frequency on the thermal characteristics are analyzed. When the duty cycle increases, the maximum dielectric surface temperature increases linearly. However, the maximum dielectric surface temperature increases nonlinearly when the input frequency varies from 0.47 MHz to 1.61 MHz. The induced flow velocity of the RF SDBD actuator is 0.25 m/s.

关键词： radio frequency discharge temperature distribution induced flow velocity plasma aerodynamic actuation

Revisiting tumor angiogenesis:vessel co-option,vessel remodeling,and cancer cell-derived vasculature formation

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Chinese Journal of Cancer 2016年第2期35卷 55-60页

作者： Chao-Nan Qian min-Han Tan Jun-Ping Yang yun Cao State Key Laboratory of Oncology in South China Collaborative Innovation Center for Cancer MedicineSun Yat-sen University Cancer Center Department of Nasopharyngeal Carcinoma Sun Yat-sen University Cancer Center Institute of Bioengineering and Nanotechnology Singapore Department of Pathology Sun Yat-sen University Cancer Center

Tumor growth and metastasis depend on the establishment of tumor vasculature to provide oxygen,nutrients,and other essential *** well-known vascular endothelial growth factor(VEGF) signaling is crucial for sprouting angiogenesis as well as recruitment of circulating progenitor endothelial cells to tumor vasculature,which has become therapeutic targets in clinical ***,the survival benefits gained from targeting VEGF signaling have been very limited,with the inevitable development of treatment *** this article,we discuss the most recent findings and understanding on how solid tumors evade VEGF-targeted therapy,with a special focus on vessel co-option,vessel remodeling,and tumor cell-derived vasculature *** co-option may occur in tumors independently of sprouting angiogenesis,and sprouting angiogenesis is not always required for tumor *** differences between vessel-like structure and tubule-like structure formed by tumor cells are also *** exploration of the underlying mechanisms of these alternative angiogenic approaches would not only widen our knowledge of tumor angiogenesis but also provide novel therapeutic targets for better controlling cancer growth and metastasis.

关键词： Angiogenesis, Vessel co-option, Vessel-like structure, Vessel remodeling, Vascular endothelial growthfactor

Production of ultrafine iron powder by low-temperature hydrogen reduction: properties change with temperature

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Journal of Iron and Steel Research International 2024年第11期31卷 2645-2654页

作者： min Gan En-di Guo Hao-rui Li yun-can Cao Xiao-hui Fan Zhi-yun Ji Zeng-qing Sun School of minerals Processing and Bioengineering Central South UniversityChangsha410083HunanChina

Ultrafine iron powder is widely used due to its excellent performance. Hydrogen reduction of fine-grained high-purity iron concentrate to prepare ultrafine iron powder has the advantages of low energy consumption, pollution-free, and low cost. The hydrogen reduction of high-purity iron concentrates, characterized by the maximum particle size of 6.43 μm when the cumulative distribution is 50% and the maximum particle size of 11.85 μm when the cumulative distribution is 90% while the total iron content of 72.10%, was performed. The hydrogen reduction could be completed at 425 ℃, and the purity of ultrafine iron powders was more than 99 wt.% in the range of 425–650 ℃. Subsequently, the effect of reduction temperature on various properties of ultrafine iron powder was investigated, including particle morphology, particle size, specific surface area, lattice parameters, bulk density, and reaction activity. It was found that the reaction activity of the iron powders prepared by hydrogen reduction was much higher than that of the products of carbonyl and liquid phase synthesis. Below 500 ℃, the reduced iron powders were nearly unbound, with a small particle size and a low bulk density. The particles had a porous surface, with a specific surface area as high as 11.31 m^(2) g^(−1). The crystallization of reduced iron powders was imperfect at this time, the amorphization degree was prominent, and the interior contained a high mechanical storage energy, which had shown high reaction reactivity. It was suitable for catalysts, metal fuels, and other functionalized applications.

关键词： High-purity iron concentrate Hydrogen reduction Ultrafine iron powder Mechanical activation High reaction activity

Mechanically scanned leaky-wave antenna based on a topological one-way waveguide

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Frontiers of physics 2020年第3期15卷 97-103页

作者： Qian Shen yun You Jie Xu yun Shen Xiaohua Deng Zhuoyuan Wang Weidong min Linfang Shen Sanshui Xiao Information Engineering School Nanchang UniversityNanchang330031China Institute of Space Science and Technology Nanchang UniversityNanchang330031China Department of Photonics Engineering Technical University of DenmarkDK-2800Kgs.LyngbyDenmark Electronic and Information Engineering College Ningbo University of TechnologyNingbo315016China School of Software Nanchang UniversityNanchang330031China Department of Applied Physics Zhejiang University of TechnologyHangzhou310023China

We propose a uniform backfire-to-endfire leaky-wave antenna(LWA)based on a topological one-way waveguide under external bias magnetic *** systematically analyze the dispersion,showing that the proposed structure supports leaky mode arisen from total internal *** means of tuning frequency or magnetic field,we obtain fixed-bias frequency and fixed-frequency bias LWA with continuous beam scanning from backward,broadside to forward *** importantly,we,for the first time,demonstrate that this proposed LWA shows mechanical tunability,allowing us to manipulate the radiation direction from backward,broadside to forward direction by mechanically tuning the air layer *** simulated results show that our system exhibits super low 3dB beam width,high radiation efficiency as well as high antenna *** provided such multiple controlled(especially mechanically)beam scanning manners,the present LWA paves an advanced approach for continuous beam scanning,holding a great potential for applications in modern communication and radar system.

关键词： leaky-wave antenna one-way waveguide magneto-optic materials

Three-dimensional modeling and reconstructive change of residual stress during machining process of milling, polishing, heat treatment, vibratory finishing, and shot peening of fan blade

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Advances in Manufacturing 2021年第3期9卷 430-445页

作者： Ji-Yin Zhang Chang-Feng Yao min-Chao Cui Liang Tan yun-Qi Sun Key Laboratory of High Performance Manufacturing for Aero Engine Northwestern Polytechnical UniversityMinistry of Industry and Information TechnologyXi’an710072People’s Republic of China Engineering Research Center of Advanced Manufacturing Technology for Aero Engine Northwestern Polytechnical UniversityMinistry of EducationXi’an710072People’s Republic of China

Residual stress during the machining process has always been a research hotspot,especially for aero-engine *** three-dimensional modeling and reconstructive laws of residual stress among various processes in the machining process of the fan blade is studied in this *** fan blades of Ti-6Al-4V are targeted for milling,polishing,heat treatment,vibratory finishing,and shot *** surface and subsurface residual stress after each process is measured by the X-ray diffraction *** distribution of the surface and subsurface residual stress is *** Rational Taylor surface function and cosine decay function are used to fit the characteristic function of the residual stress distribution,and the empirical formula with high fitting accuracy is *** value and distribution of surface and subsurface residual stress vary greatly due to different processing *** reconstructive change of the surface and subsurface residual stress of the blade in each process intuitively shows the change of the residual stress between the processes,which has a high reference significance for the research on the residual stress of the blade processing and the optimization of the entire blade process.

关键词： Fan blade Machining process Surface residual stress Subsurface residual stress Three-dimensional modeling Reconstructive change

New insights into the life history of Monochamus saltuarius(Cerambycidae:Coleoptera)can enhance surveillance strategies for pine wilt disease

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Journal of Forestry Research 2021年第6期32卷 2699-2707页

作者： min Li yun Dai Yang Wang Lichao Wang Shouhui Sun Fengmao Chen Co-Innovation Center for Sustainable Forestry in Southern China College of ForestryNanjing Forestry UniversityNanjing 210037China College of Forestry Shenyang Agricultural UniversityShenyang 110866China

Pine wilt disease was first discovered in Dongtang town,Liaoning Province,China,in *** saltuarius Gebler is a new vector of pinewood nematode and the only known vector in Liaoning *** biology of this pest has not been reported thus far;therefore,it is necessary to study its life *** 2018 and 2019,we collected 138 and 491 adult *** beetles,respectively,to analyze their eclosion from larva to adult *** mid-March,overwintering larvae began to feed(on xylem)and seek nutrition in preparation for pupation and *** adults began to appear in mid-April,and the population reached its peak in late *** life span of the adults was 28-76 *** approximately 1 week of supplemental nutrition(feeding on twigs),adults began to mate and lay *** egg stage of *** lasted 4-8 *** larvae in Dongtang town have 4 instars and overwinter in tunnels as 3rd-4th *** 1st-instar stage lasted 3-9 days,the 2nd-instar stage lasted 11-23 days,the 3rd-instar stage lasted 30-130 days,and the 4th-instar stage lasted 44-180 *** pupal stage lasted 7-12 days,and the life span of the adults was 28-76 *** this study we systematically monitored the life history of *** for the first *** objective was to lay a foundation for improving control of this pinewood nematode vector.

关键词： Bursaphelenchus xylophilus China Pine sawyer Life cycle Vector