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Design of Neutral Beam-Line of EAST 被引量:1
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作者 胡纯栋 梁立振 +8 位作者 谢远来 韦江龙 谢亚红 李军 刘智民 刘胜 蒋才超 盛鹏 许永建 《Plasma Science and Technology》 SCIE EI CAS CSCD 2011年第5期541-545,共5页
Neutral beam injector for EAST is designed to deliver deuterium beams with a power of 2 MW to 4 MW at an energy of 50 keV to 80 keV into the plasma with a beam dimension of 12 cm× 48 cm. Considering the beam gene... Neutral beam injector for EAST is designed to deliver deuterium beams with a power of 2 MW to 4 MW at an energy of 50 keV to 80 keV into the plasma with a beam dimension of 12 cm× 48 cm. Considering the beam generation and transmission, a columniform beam-line of Ф 250 cm × 400 cm is designed with a neutralizer, ion dump, calorimeter, bending magnet and cryopanels. The arrangement of the internal elements for the beam-line is reported. A rectangular sleeve coupled to the ion source is employed as the neutralizer. At the downstream of the neutralizer, a dipole magnet separates the residual ions from the beam passage with a reflection radius of 42 cm for the full energy particles. The calorimeter and the ion dump serve as high heat flux components, which will work as thermal inertia targets in the first phase of operation. 展开更多
关键词 neutral beam experimental advanced superconducting tokamak (EAST) beam-line
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Breeding lines with neutral genes to improve fertility of intersubspecific hybrid rice
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作者 IKEHASHI Hiroshi 《Chinese Rice Research Newsletter》 2002年第1期6-7,共2页
Since the sterility-neutral allele S~n has been incorporatedinto indica or japonica varieties, many intersubspecifichybrids have been released commercially. These hybridsshowed high heterosis, but some of them exhibit... Since the sterility-neutral allele S~n has been incorporatedinto indica or japonica varieties, many intersubspecifichybrids have been released commercially. These hybridsshowed high heterosis, but some of them exhibited unstableseed setting rate under low temperature. When the hybridsflowered at low temperature, the fertility of female gamete 展开更多
关键词 Breeding lines with neutral genes to improve fertility of intersubspecific hybrid rice
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基于信号图像化和CNN-ResNet的配电网单相接地故障选线方法 被引量:2
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作者 缪欣 张忠锐 +1 位作者 郭威 侯思祖 《中国测试》 CAS 北大核心 2024年第6期157-166,共10页
配电网发生单相接地故障时,零序电流呈现较强的非线性与非平稳性,故障选线较为困难,针对此问题,提出一种基于信号图像化和卷积神经网络-残差网络的配电网单相接地故障选线方法。首先,利用排列熵优化变分模态分解算法的参数,将零序电流... 配电网发生单相接地故障时,零序电流呈现较强的非线性与非平稳性,故障选线较为困难,针对此问题,提出一种基于信号图像化和卷积神经网络-残差网络的配电网单相接地故障选线方法。首先,利用排列熵优化变分模态分解算法的参数,将零序电流信号分解成一系列固有模态函数;其次,引入新的数据预处理方式,将固有模态函数转成二维图像,获得零序电流信号的时频特征图;最后,利用一维卷积神经网络提取零序电流信号的相关性和特征,利用残差网络提取时频特征图的特征,将两个网络融合,构建混合卷积神经网络结构,实现故障选线。仿真与实验结果表明,该方法能够在高阻接地、采样时间不同步、强噪声等情况下准确地选择出故障线路,可满足配电网对故障选线准确性和可靠性的需求。 展开更多
关键词 变分模态分解 卷积神经网络 残差网络 故障选线 排列熵
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NT4(Si)-p53(N15)-antennapedia induces cell death in a human hepatocellular carcinoma cell line 被引量:8
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作者 Li-Ping Song Yue-Ping Li +5 位作者 Ning Wang Wei-Wei Li Juan Ren Shu-Dong Qiu Quan-Ying wang Guang-Xiao Yang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第46期5813-5820,共8页
AIM: To construct the recombinant lentivirus expression plasmid, pLenti6/V5-NT4 p53(N 15)-antennapedia (Ant), and study its effect on HepG2 cells. METHODS: Plasmid pLenti6/V5-NT4 p53(N15)-Ant was constructed i... AIM: To construct the recombinant lentivirus expression plasmid, pLenti6/V5-NT4 p53(N 15)-antennapedia (Ant), and study its effect on HepG2 cells. METHODS: Plasmid pLenti6/V5-NT4 p53(N15)-Ant was constructed incorporating the following functional regions, including signal peptide sequence and proregion of neurotrophin 4, N-terminal residues 12-26 of p53 and 17 amino acid drosophila carrier protein, Ant. Hepatocellular carcinoma (HepG2) cells were used for transfection. 3-[4,5-climethyl-thiazol-2yl]-2,5 diphenyl tetrazolium bromide (MI-I) assay, lactate dehydrogenase (LDH) release assay, transmission electron microscopy (TEM) and flow cytometric analysis (FCM) were employed to investigate the effects of LV-NT4(Si)- p53(N15)-Ant in vitro on HepG2 cells. In vivo experiment was also performed to investigate the inhibitory effect of LV-NT4(Si)-p53(N15)-Ant on tumor growth in nude mice.RESULTS: LV-NT4(Si)-p53(N15)-Ant significantly suppressed the growth of HepG2 cells. MTT assay showed that the growth of HepG2 cells was mucj more significantly inhibited by LV-NT4(Si)-p53(N15)-Ant than by LV-EGFP. The inhibition rate for HepG2 cell growth in the two groups was 46.9% and 94.5%, respectively, 48 h after infection with LV-NT4(Si)-p53(N15)-Ant, and was 33.9% and 95.8%, respectively, 72 h after infection with LV-NT4(Si)-p53(N15)-Ant (P 〈 0.01). Light microscopy and TEM showed morphological changes in HepG2 cells infected with LV-NT4(Si)-p53(N15)-Ant, but no significant changes in HepG2 cells infected with LV-EGFR Changes were observed in ultra-structure of HepG2 cells infected with LV-NT4(Si)-p53(N15)-Ant, with degraded membranes, resulting in necrosis. LDH release from HepG2 cells was analyzed at 24, 48, 72 and 96 h after infection with LV-NT4(Si)-p53(N15)-Ant and LV-EGFP, which showed that LDH release was significantly higher in LV-NT4(Si)-p53(N15)-Ant treatment group (682 IU/L) than in control group (45 IU/L, P 〈 0.01). The longer the time was after infection, the bigger the difference was in LDH release. FCM analysis showed that LV-NT4(Si)- p53(N15)-Ant could induce two different kinds of cell death: necrosis and apoptosis, with apoptosis being the minor type and necrosis being the main type, suggesting that LV-NT4(Si)-p53(N15)-Ant exerts its anticancer effect on HepG2 cells by inducing necrosis. The in vivo study showed that LV-NT4(Si)-p53(N15)-Ant significantly inhibited tumor growth with an inhibition rate of 66.14% in terms of tumor size and weight. CONCLUSION: LV-NT4(Si)-p53(N15)-Ant is a novel recombinant lentivirus expression plasmid and can be used in gene therapy for cancer. 展开更多
关键词 Gene therapy Lentivirus vector AnTICAnCER nECROSIS LV-nT4(Si)-p53(n15)-Ant Hepatocellularcarcinoma cell line
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Delay-dependent stability analysis of Runge-Kutta methods for neutral delay differential equations 被引量:1
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作者 宋明辉 刘明珠 B S SIDIBE 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2002年第2期129-135,共7页
The aim of this paper is to study the asymptotic stability properties of Runge Kutta(R-K) methods for neutral differential equations(NDDEs) when they are applied to the linear test equation of the form: y′(t)=ay(t)... The aim of this paper is to study the asymptotic stability properties of Runge Kutta(R-K) methods for neutral differential equations(NDDEs) when they are applied to the linear test equation of the form: y′(t)=ay(t)+by(t-τ)+cy’(t-τ), t>0, y(t)=g(t), -τ≤t≤0, with a,b,c∈[FK(W+3mm\.3mm][TPP129A,+3mm?3mm,BP], τ>0 and g(t) is a continuous real value function. In this paper we are concerned with the dependence of stability region on a fixed but arbitrary delay τ. In fact, it is one of the N.Guglielmi open problems to investigate the delay dependent stability analysis for NDDEs. The results that the 2,3 stages non natural R-K methods are unstable as Radau IA and Lobatto IIIC are proved. And the s stages Radau IIA methods are unstable, however all Gauss methods are compatible. 展开更多
关键词 neutral delay differention equation natural RUnGE-KUTTA methods nт(0)-stability nт(0)-com patibility
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Reconstructed annual glacier surface mass balance in theányêmaqên Mountains,Yellow River source,based on snow line altitude 被引量:1
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作者 LI Kai-ji CAO Bo +2 位作者 GUAN Wei-jin PAN Bao-tian SHANGGUAN Dong-hui 《Journal of Mountain Science》 SCIE CSCD 2022年第4期1070-1081,共12页
Annual mass balance is an important factor that reflects glacier change and glacier meltwater resources.In this study,we analyzed the changes in glacier area,snow line altitude(SLA)and surface elevation in theány... Annual mass balance is an important factor that reflects glacier change and glacier meltwater resources.In this study,we analyzed the changes in glacier area,snow line altitude(SLA)and surface elevation in theányêmaqên Mountain region using multisource remote sensing data.Then,the annual mass balance of two glaciers was reconstructed by using SLA-mass-balance gradient method.The results showed that the glacier area in theányêmaqên Mountains decreased by 29.4 km2from 1985 to 2017.The average SLAs of the Halong Glacier and Yehelong Glacier were approximately 5290 m and 5188 m,respectively.The glacier mass balance for the two glaciers from 1990 to 2020 was-0.71 m w.e.a^(-1) and-0.63 m w.e.a^(-1),respectively.Our results indicate that SLA is an important indicator of glacier changes,and a long sequence of SLAs can more accurately reconstruct the glacier mass balance of the glacier.The mean annual glacial meltwater-fed streamflow is 1.45×10^(7)m^(3) and 1.12×10^(7)m^(3),respectively.Sensitivity analysis indicates that summer air temperature plays a leading role in regard to the influential climatic factors of glacial retreat in theányêmaqên Mountains.This highlights the potential of the methodology for application on reconstructing annual glacier surface mass balance at larger scales without direct measurements. 展开更多
关键词 Snow line altitude(SLA) Glacier annual mass balance reconstruction Glacier changes ányêmaqên Mountains
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In vitro cytotoxicity of Indonesian stingless bee products against human cancer cell lines 被引量:1
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作者 Paula M.Kustiawan Songchan Puthong +1 位作者 Enos T.Arung Chanpen Chanchao 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2014年第7期549-556,共8页
Objective:To screen crude extracts of propolis,bee pollen and honey from four stingless bee species[Trigona incisa(T.incisa)],Timia apicalis,Trigona fuso-baltata and Trigona filscibasis)native to East Kalimantan.Indon... Objective:To screen crude extracts of propolis,bee pollen and honey from four stingless bee species[Trigona incisa(T.incisa)],Timia apicalis,Trigona fuso-baltata and Trigona filscibasis)native to East Kalimantan.Indonesia for cytotoxic activity against five human cancer cell lines(HepG2,SW620,ChaGo-1,KATO-Ⅲand BT474).Methods:All samples were extracted with methanol,and then subpartitioned with n-hexane and ethyl acetate.Each crude extract was screened at 20μg/mL for in vitro cytotoxicity against the cell lines using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay.Tn addition,four previously shown bioactive components from propolis(apigenin,cafieic acid phenyl ester,kaempferol and naringenin)and two chemotherapeutic drugs(doxorubicin and 5-fluorouracil)were used to evaluate the sensitivity of the cell lines.Results:Overall,crude extracts from propolis and honey had higher cytotoxic activities than bee pollen,but the activity was dependent upon the extraction solvent,bee species and cell line.Propolis extracts from T.incisa and Tarda apicalis showed the highest and lowest cytotoxic activity,respectively.Only the HepG2 cell line was broadly sensitive to the honey extracts.For pure compounds,doxorubicin was the most cytotoxic,the four propolis compounds the least,but the ChaGo-I cell line was sensitive to kaempferol at 10μg/mL and KATO-Ⅲwas sensitive to kaempferol and apigenin at 10μg/mL,.All pure compounds were effective against the BT474 cell line.Conclusions:Propolis from f,incisa and Trigona fusco-balteata contain an in vitro cytotoxic activity against human cancer cell lines.Further study is required,including the isolation and characterization of the active antiproliferative agent(s). 展开更多
关键词 AnTIPROLIFERATIVE activity BEE product Cancer cell lines Cytotoxicity Ethyl acetate extract n-HEXAnE HOnEY Methanol PROPOLIS
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m-degree Center-connecting Line of Finite Points Set and Its Properties 被引量:1
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作者 ZHOU Yong-guo 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第2期247-252,共6页
In this paper, we first give the concept of m-degree center-connecting line in n-dimensional Euclidean space Enand investigate its several properties, then we obtain the length of m-degree center-connecting line formu... In this paper, we first give the concept of m-degree center-connecting line in n-dimensional Euclidean space Enand investigate its several properties, then we obtain the length of m-degree center-connecting line formula in finite points set. As its application,we extend the Leibniz formula and length of medians formula in n-dimensional simplex to polytope. 展开更多
关键词 n-dimensional Euclidean space finite points set m-degree center-connectingline PROPERTIES
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On the Line Graph of the Complement Graph for the Ring of Gaussian Integers Modulo n
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作者 Manal Ghanem Khalida Nazzal 《Open Journal of Discrete Mathematics》 2012年第1期24-34,共11页
The line graph for the complement of the zero divisor graph for the ring of Gaussian integers modulo n is studied. The diameter, the radius and degree of each vertex are determined. Complete characterization of Hamilt... The line graph for the complement of the zero divisor graph for the ring of Gaussian integers modulo n is studied. The diameter, the radius and degree of each vertex are determined. Complete characterization of Hamiltonian, Eulerian, planer, regular, locally and locally connected is given. The chromatic number when is a power of a prime is computed. Further properties for and are also discussed. 展开更多
关键词 Complement of a GRAPH Chromatic Index Diameter DOMInATIOn number Eulerian GRAPH GAUSSIAn InTEGERS Modulo n Hamiltonian GRAPH line GRAPH Radius Zero DIVISOR GRAPH
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Over Voltage Fault due to Disconnection of Consumer’s Transformer Neutral Wire
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作者 Erdene Adiyasuren Enkh-Od Erdene +1 位作者 Sergelen Byambaa Shagdarsuren Gantumur 《Journal of Energy and Power Engineering》 2023年第1期11-14,共4页
Practically,the load currents in three phases are asymmetric in the power system.It means that the impedances are different in all three phases.If the consumer’s transformer neutral cut off and/or was disconnected fr... Practically,the load currents in three phases are asymmetric in the power system.It means that the impedances are different in all three phases.If the consumer’s transformer neutral cut off and/or was disconnected from the neutral of power supply source,then there will be some trouble and failure occurred.The current in the neutral wire drops down to zero when the neutral wire is cut off and the phase currents of all three-phase equal to each other since there was no return wire.The currents are equal but the voltages at the phase consumers are different.Especially for residential single-phase consumers,the voltage at the consumers of the phase varies differently for three phase systems when the neutral wire was disconnected at consumer side and even the voltage at the consumers one or two of those three phases becomes over nominal voltage or reaches nearly line voltage.In this case,the electronic appliances in that phase will be fed by high voltage than the rated value and they can be broken down.In the power system of UB(Ulaanbaatar)city,there are some occasional such kind of failures every year.Obviously,many electronic appliances were broken down due to high voltage and the electricity utility companies respond for service charge of damaged parts. 展开更多
关键词 neutral connection and neutral wire phase and line voltage single-phase residential consumer transformer neutral cut off asymmetric load current protective earth
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Prediction of a neutralizing epitope of a H5N1 virus hemagglutinin complexed with an antibody variable fragment using molecular dynamics simulation
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作者 Cenmidtal C. Mulyanto Rosari Saleh 《Journal of Biophysical Chemistry》 2011年第3期258-267,共10页
In this present study, we predicted the neutralizing epitope of a modeled H5N1 hemagglutinin 1046T when interacted with a modeled monoclonal antibody variable fragment 8H5Fv using molecular dynamics simulation. Follow... In this present study, we predicted the neutralizing epitope of a modeled H5N1 hemagglutinin 1046T when interacted with a modeled monoclonal antibody variable fragment 8H5Fv using molecular dynamics simulation. Following the production run of the molecular dynamics simulation, we observed the average change of solvent accessible surface of the antigen alongside the formation of hydrogen bonds between the two structures during the simulation. Based on the acquired data, we predicted the neutralizing epitope of the 1046T antigen to be consisted of residues Asp 84, Glu85, Phe86, Ile87, Asn88, Val89, Pro90, Ile132, Ser136, Val147, Pro152, Tyr153, Leu154, Arg161, and Tyr268. By calculating the RMSD of the Cα backbone chain of the complex during the simulation we found the structure to be generally stable suggesting a well maintained steric hindrance, while RMSD calculation of the predicted neutralizing epitope backbone suggests the stability of the neutralizing epitope itself. 展开更多
关键词 MOLECULAR Dynamics Simulation neutralIZInG EPITOPE AnTIBODY H5n1 HEMAGGLUTInIn MOLECULAR DOCKInG
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Modeling and Simulation of Hydraulic Long Transmission Line by Bond Graph
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作者 Dragan Prsie Novak Nedie Ljubisa Dubonjie 《Journal of Mechanics Engineering and Automation》 2013年第4期257-262,共6页
This paper addresses the issue of modeling of the hydraulic long transmission line. In its base, such model is nonlinear with distributed parameters. Since general solution in closed-form for such model in time-domain... This paper addresses the issue of modeling of the hydraulic long transmission line. In its base, such model is nonlinear with distributed parameters. Since general solution in closed-form for such model in time-domain is not available, certain simplifications have to be introduced. The pipeline in the paper has been divided to a cascaded network of n segments so that a model with lumped parameters could be reached. For segment modeling, a standard library of bond graphs element has been used. On the basis of models with lumped parameters, the effect of the number of segments, pipeline length and effective bulk modulus on the dynamics of long transmission line have been analyzed. 展开更多
关键词 Long transmission line lumped parameters n segments bond graph
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碳中和目标下负排放策略的综合效应——基于N‑DSGE模型的数值模拟分析
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作者 沈维萍 夏克郁 陈迎 《中国人口·资源与环境》 CSSCI CSCD 北大核心 2024年第2期13-22,共10页
全球气候变化已达“气候紧急状态”,包括中国在内的诸多国家和地区先后宣布碳中和目标和净零排放承诺。在气候变化减缓和传统的适应措施之外,自然科学领域和气候经济学领域探讨负排放技术经济可行性的研究越来越多,但从可持续发展经济... 全球气候变化已达“气候紧急状态”,包括中国在内的诸多国家和地区先后宣布碳中和目标和净零排放承诺。在气候变化减缓和传统的适应措施之外,自然科学领域和气候经济学领域探讨负排放技术经济可行性的研究越来越多,但从可持续发展经济学视角对负排放技术综合效应的评估还比较少。该研究基于可持续发展经济学的生态价值理论,将气候变化综合评估模型与宏观经济学动态随机一般均衡(DSGE)模型相结合,构建包含自然生态系统部门的N‑DSGE模型,对负排放技术的气候效应、生态效应、经济效应以及福利效应进行综合评估。评估结果表明:①当可用技术条件下传统减排措施达到最大减排潜力后,可以依靠负排放技术实现净零排放乃至净负排放。②低强度、小规模实施负排放技术具有正向的气候、生态和经济效应,然而随着负排放技术实施强度增大,气候效应增强,经济效应削弱,社会综合福利明显降低。③敏感性分析证明了评估结果的稳健性,并进一步表明负排放技术的实施效果会受到传统减排水平和自然碳汇能力的影响。基于评估结果,应谨慎扩大负排放技术实施规模和实施强度,加强科学技术研发,降低技术成本;对不同负排放技术采取差异化发展策略;加强负排放技术实施的治理,尽可能避免和最小化其负面影响,促进气候、生态和经济等可持续发展目标的协同;部署负排放技术不应放松传统减排的努力,应降低碳达峰峰值,同时提升自然生态系统的碳汇能力。 展开更多
关键词 碳中和目标 负排放技术 n‑DSGE模型 生态价值 福利效应
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表达猪流行性腹泻病毒N蛋白Vero细胞系的构建及初步鉴定
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作者 卢峥朴 赵平 +3 位作者 陈樱 韦祖樟 黄伟坚 欧阳康 《广西农学报》 2024年第1期27-32,共6页
【目的】构建表达猪流行性腹泻病毒(PEDV)N蛋白的Vero细胞系,将有助于PEDV的进一步深入研究。【方法】本研究将N基因克隆到慢病毒载体中,构建重组质粒pLenti-CMV-N,利用慢病毒载体包装系统转染293T细胞,包装表达N蛋白的慢病毒颗粒,将慢... 【目的】构建表达猪流行性腹泻病毒(PEDV)N蛋白的Vero细胞系,将有助于PEDV的进一步深入研究。【方法】本研究将N基因克隆到慢病毒载体中,构建重组质粒pLenti-CMV-N,利用慢病毒载体包装系统转染293T细胞,包装表达N蛋白的慢病毒颗粒,将慢病毒颗粒转导至Vero细胞,用潮霉素B初步筛选阳性细胞,采用终点稀释法,筛选表达PEDV N蛋白的Vero细胞系,最后进行鉴定。【结果】RT-PCR结果表明构建的细胞系基因组中存在N基因序列,Western blot和IFA试验验证了N蛋白在细胞系中的表达。【结论】本研究成功构建了表达PEDV N蛋白的Vero细胞系。 展开更多
关键词 PEDV n蛋白 细胞系 慢病毒载体
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Reducing Numerical Oscillations through Modified Circuits for Inclusion of Frequency Influence in Transmission Line Representation
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作者 Leonardo S. Lessa Afonso J. Prado +2 位作者 Sdrgio Kurokawa Luiz F. Bovolato Jos6 Pissolato Filho 《Journal of Energy and Power Engineering》 2012年第11期1800-1808,共9页
In this article, a transmission line is represented by a cascade of n circuits using a single phase. It is analyzed what is the reasonable number of n circuits and the number of blocks composed by parallel resistor an... In this article, a transmission line is represented by a cascade of n circuits using a single phase. It is analyzed what is the reasonable number of n circuits and the number of blocks composed by parallel resistor and inductor in parallel for reduction of numerical oscillations. It is simulated the numerical routine with and without the effectof frequency in the longitudinal parameters. Initially, it is used to state variables and 7t circuits representing the transmission line composing a linear system which is solved by numerical routines based on the trapezoidal rule. The effect of frequency on the line is synthesized by resistors and inductors in parallel and this representation is analyzed in details. It is described as transmission lines and the frequency influence in these lines through the state variables. 展开更多
关键词 Electromagnetic transient EMTP mathematical model simulation transmission lines n circuit numeric method wavetraveling.
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C_(4)F_(7)N/CO_(2)/O_(2)混合气体近区故障开断性能研究
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作者 赵启 刘绍勇 +3 位作者 罗金文 王子寒 王海斌 殷晓刚 《高压电器》 CAS CSCD 北大核心 2024年第9期85-91,共7页
六氟化硫(SF_(6))气体因其具有优良的绝缘与灭弧性能,现已广泛应用于电力设备中,但由于其具有强温室效应,随着全球变暖问题的日益严重,急需寻找能够替代SF_(6)的新型环保气体。其中,全氟异丁腈(C_(4)F_(7)N)具有优异的绝缘性能,有良好... 六氟化硫(SF_(6))气体因其具有优良的绝缘与灭弧性能,现已广泛应用于电力设备中,但由于其具有强温室效应,随着全球变暖问题的日益严重,急需寻找能够替代SF_(6)的新型环保气体。其中,全氟异丁腈(C_(4)F_(7)N)具有优异的绝缘性能,有良好的工程应用前景,然而目前尚无针对C_(4)F_(7)N/CO_(2)/O_(2)混合气体断路器的近区故障开断特性研究。文中针对126 k V/3 150 A/40 k A柱式C_(4)F_(7)N混合气体断路器的近区故障开断性能进行研究,对比了断路器充入C_(4)F_(7)N/CO_(2)/O_(2)混合气体、CO_(2)/O_(2)混合气体和SF_(6)气体在不同电流过零时电流下降率(di/dt)下的近区故障开断性能。L90近区故障开断实验结果显示,在相同条件下SF_(6)气体表现出最佳的开断性能,能够在较宽的燃弧时间窗口内稳定开断实验电流。0.7 MPa的C_(4)F_(7)N/CO_(2)/O_(2)混合气体和CO_(2)/O_(2)混合气体在di/dt=12 A/μs条件下的开断表现与0.5 MPa的SF_(6)气体在di/dt=20 A/μs条件下的开断表现接近。基于实验结果提出了灭弧室结构的改进方案,并进行了实验验证文中的研究为C_(4)F_(7)N混合气体断路器的开发与设计提供了参考。 展开更多
关键词 SF_(6)替代气体 C_(4)F_(7)n 混合气体 近区故障 开断性能
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Spectrometric Measurement of Plasma Parameters Utilizing the Target Ambient Gas O I &N I Atomic Lines in LIBS Experiment
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作者 Ashraf M. El Sherbini Abdel Aziz Saad Al Amer +1 位作者 Ahmed T. Hassan Tharwat M. El Sherbini 《Optics and Photonics Journal》 2012年第4期286-293,共8页
In this article, we shall report the results of the spectroscopic measurements of the plasma parameters utilizing the spectral lines emitted from the air atoms surrounding plasma (O I line at 777.19 nm and N I at 746.... In this article, we shall report the results of the spectroscopic measurements of the plasma parameters utilizing the spectral lines emitted from the air atoms surrounding plasma (O I line at 777.19 nm and N I at 746.83 nm). The plasma was created via irradiation of plane solid aluminum target in open air by a high peak power Nd: YAG laser pulses at fundamental wavelength of 1064 nm. The emission spectra were recorded using Echelle type spectrograph in conjunction with a time gated ICCD camera at different delay time from 1 to 5 μs and at a fixed gate time of 1 μs. The plasma electron density was measured utilizing the Stark broadening of the N I and O I lines and then compared to the reference density as deduced from the optically thin Hα-line at 656.27 nm appeared in the same emission spectra. The results show that under our experimental conditions the air lines are subjected to moderate absorption. The plasma electron temperature was measured utilizing the relative spectral intensity of the air (O I to N I) lines after correcting their spectral radiance against absorption. The standard temperature was measured utilizing the Al II ionic lines. A comparison to the reference temperatures shows a very close agreement after correcting the emission spectral radiance of the air lines against self absorption, which emphasizes the importance of correction process. 展开更多
关键词 LIBS Self Absorption O I-n I lineS Plasma Parameters
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Behavioral Characteristics of Pharmacologically Selected Lines of Rats: Relevance to Depression
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作者 Darin J. Knapp Lynette C. Daws David H. Overstreet 《World Journal of Neuroscience》 2014年第3期225-239,共15页
This brief review discusses the behavioral consequences of two pharmacologically selected lines of rats. Flinders Sensitive (FSL) and Flinders Resistant (FRL) Lines of rats were selected on the basis of differential h... This brief review discusses the behavioral consequences of two pharmacologically selected lines of rats. Flinders Sensitive (FSL) and Flinders Resistant (FRL) Lines of rats were selected on the basis of differential hypothermic and behavioral responses to the anticholinesterase, diisopropylfluorophosphate (DFP). FSL rats are more sensitive to the hypothermic effects of cholinergic, serotonergic, and dopaminergic agonists but less sensitive to the locomotor or stereotypic effects of dopamine agonists. FSL rats exhibit greater immobility in the forced swim test and reduced social interaction compared with FRL rats, but do not differ in saccharin intake, behavior in the elevated plus maze, or responses for rewarding brain self-stimulation. The exaggerated immobility and reduced social interaction are counteracted by chronic treatment with antidepressants. Because FSL rats were more sensitive to 5-HT1A receptor agonists, high (HDS) and low (LDS) 8-OH-DPATsensitive lines were selectively bred for differential hypothermic responses to the 5-HT1A receptor agonist, 8-hydroxy-2-(di-N-propylamino)tetralin (8-OH-DPAT). HDS rats were also more sensitive to the hypothermic effects of oxotremorine, a cholinergic agonist, but selection for this response did not diverge with later selection. HDS rats exhibited greater immobility in the forced swim test than LDS rats and this correlated response could be seen early in selection (generation 3). HDS rats also showed reduced social interaction compared to LDS rats, but did not differ in behavior in the elevated plus maze. These findings confirm that selection for hypothermic responses to pharmacological agents do have behavioral consequences, notably the production of depressive-like phenotypes, which can be counteracted by chronic antidepressant treatment. Because increased 5-HT1A receptor sensitivity was common to both selected lines (FSL and HDS), neurobiological processes dependent on this receptor could contribute to the abnormal behaviors that manifest in these rat lines and thus suggesting a mechanism underlying depressive behaviors in humans. However, available human data are inconsistent with this hypothesis and suggest that other mechanisms underlie these behavioral abnormalities in HDS and FSL rats. These mechanisms as well as additional behavioral testing in these rat lines will be discussed. 展开更多
关键词 Diisopropylfluorophosphate (DFP) 8-Hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) Flinders SEnSITIVE line (FSL) Flinders Resistant line (FRL) RATS High and Low 8-OH-DPAT SEnSITIVE (HDS & LDS) RATS Muscarinic RECEPTORS 5-HT1A RECEPTORS Forced Swim Test Social Interaction Test Elevated Plus Maze DEPRESSIOn Anxiety
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GC/MS图谱中N,N′-二苯基脲的中性丢失 被引量:6
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作者 袁新华 张丽芳 +1 位作者 倪中海 魏贤勇 《江苏大学学报(自然科学版)》 EI CAS 2003年第2期54-57,共4页
常温常压下苯胺与CO2在AlCl3催化作用下发生反应,对反应混合物用乙醇重结晶,获得无色针状晶体,GC/MS分析表明该晶体为异氰酸苯酯 用熔点测定、HPLC/MS/MS、FTIR、UV和1HNMR等手段对此晶体进行分析,确定其为N,N′-二苯基脲 研究了N,N′-... 常温常压下苯胺与CO2在AlCl3催化作用下发生反应,对反应混合物用乙醇重结晶,获得无色针状晶体,GC/MS分析表明该晶体为异氰酸苯酯 用熔点测定、HPLC/MS/MS、FTIR、UV和1HNMR等手段对此晶体进行分析,确定其为N,N′-二苯基脲 研究了N,N′-二苯基脲的质谱裂解机理,实验结果表明N,N′-二苯基脲质谱裂解中可能发生了中性丢失,丢失了中性分子苯胺。 展开更多
关键词 中性丢失 n n’-二苯基脲 质谱 GC/MS图谱
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基于线电压坐标系的ANPC-5L逆变器SVPWM算法的研究 被引量:23
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作者 谭国俊 刘战 +2 位作者 叶宗彬 李浩 李探 《中国电机工程学报》 EI CSCD 北大核心 2013年第30期26-33,6,共8页
在6~10kV的高压变频领域,与传统拓扑结构相比,有源中点箝位型五电平(active neutral-point-clampedfive-1evel,ANPC-5L)逆变器具有很高的实用价值。针对传统五电平逆变器空间矢量脉宽调制(spac evector pulse width modulation,... 在6~10kV的高压变频领域,与传统拓扑结构相比,有源中点箝位型五电平(active neutral-point-clampedfive-1evel,ANPC-5L)逆变器具有很高的实用价值。针对传统五电平逆变器空间矢量脉宽调制(spac evector pulse width modulation,SVPWM)控制算法复杂、计算量大等缺点,研究一种基于线电压坐标系的SVPWM控制算法,通过进行坐标变换,减少对基本矢量的确定步骤,简化基本矢量对应作用时间的求解过程,并将其应用到ANPC-5L逆变器中,通过实验波形和电流谐波分析证明控制算法的正确性。结合ANPC-5L逆变器和新控制算法的特点,提出一种高效的中点电压平衡的控制算法,通过对中点电位的检测和判断计算出所需的开关序列及复用矢量的作用时间比值,实现中点电流流入与流出的平衡,进而达到控制中点电压平衡的目的。实验结果证明了该中点控制算法有效性。 展开更多
关键词 AnPC-5L逆变器 线电压坐标系 SVPWM 中点 电压平衡
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