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A catalog of early-type emission-line stars and Hα line profiles from LAMOST DR2 被引量:1
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作者 Wen Hou A-Li Luo +9 位作者 Jing-Yao Hu Hai-Feng Yang Chang-De Du Chao Liu Chien-De Lee Chien-Cheng Lin Yue-Fei Wang Yong Zhang Zi-Huang Cao Yong-Hui Hou 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2016年第9期39-50,共12页
We present a catalog including 11 204 spectra of 10436 early-type emission-line stars from LAMOST DR2, among which 9752 early-type emission-line spectra are newly discovered. For these early- type emissionqine stars, ... We present a catalog including 11 204 spectra of 10436 early-type emission-line stars from LAMOST DR2, among which 9752 early-type emission-line spectra are newly discovered. For these early- type emissionqine stars, we discuss the morphological and physical properties of their low-resolution spectra. In this spectral sample, the Hα emission profiles display a wide variety of shapes. Based on the Hα line profiles, these spectra are categorized into five distinct classes: single-peak emission, single-peak emission in absorption, double-peak emission, double-peak emission in absorption, and P-Cygni profiles. To better understand what causes the Hc~ line profiles, we divide these objects into four types from the perspective of physical classification, which include classical Be stars, Herbig Ae/Be stars, close binaries and spectra contaminated by H n regions. The majority of Herbig Ae/Be stars and classical Be stars are identified and separated using a (H-K, K-W1) color-color diagram. We also discuss 31 binary systems that are listed in the SIMBAD on-line catalog and identify 3600 spectra contaminated by HⅡ regions after cross-matching with positions in the Dubout-Crillon catalog. A statistical analysis of line profiles versus classifications is then conducted in order to understand the distribution of Hc~ profiles for each type in our sample. Finally, we also provide a table of 172 spectra with Fen emission lines and roughly calculate stellar wind velocities for seven spectra with P-Cygni profiles. 展开更多
关键词 STARS early-type - stars emission-line Be -- stars pre-main sequence -- binaries close
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Type Synthesis of 4-DOF Parallel Kinematic Mechanisms Based on Grassmann Line Geometry and Atlas Method 被引量:22
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作者 XIE Fugui LI Tiemin LIU Xinjun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第6期1073-1081,共9页
Many methods are proposed to deal with the type synthesis of parallel kinematic mechanisms(PKMs), but most of them are less intuitive to some extent. Thus, to propose a concise and intuitive type synthesis method fo... Many methods are proposed to deal with the type synthesis of parallel kinematic mechanisms(PKMs), but most of them are less intuitive to some extent. Thus, to propose a concise and intuitive type synthesis method for engineering application is a very challenging issue, which should be further studied in the field. Grassmann line geometry, which can investigate the dimensions of spatial line-clusters in a concise way, is taken as the mathematic foundation. Atlas method is introduced to visually describe the degrees of freedom(DOFs) and constraints of a mechanism, and the dual rule is brought in to realize the mutual conversion of the freedom-space and constraint-space. Consequently, a systematic method based on Grassmann line geometry and Atlas method is generated and the entire type synthesis process is presented. Three type 4-DOF PKMs, i.e., 1T3R, 2T2R and 3T1R(T: translational DOF; R: rotational DOF), are classified according to the different combinations of the translational DOFs and rotational DOFs. The type synthesis of 4-DOF PKMs is carried out and the possible configurations are thoroughly investigated. Some new PKMs with useful functions are generated during this procedure. The type synthesis method based on Grassmann line geometry and Atlas method is intuitive and concise, and can reduce the complexity of the PKMs' type synthesis. Moreover, this method can provide theoretical guidance for other PKMs' type synthesis and engineering application. A novel type synthesis method is proposed, which solves the existing methods' problems in terms of complicated, not intuitive and unsuitable for practical application. 展开更多
关键词 type synthesis parallel kinematic mechanism Grassmann line geometry atlas method
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Characterization of QTL for unique agronomic traits of new-plant-type rice varieties using introgression lines of IR64 被引量:3
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作者 Analiza G.Tagle Daisuke Fujita +5 位作者 Leodegario A.Ebron Mary Jeanie Telebanco-Yanoria Kazuhiro Sasaki Tsutomu Ishimaru Yoshimichi Fukuta Nobuya Kobayashi 《The Crop Journal》 SCIE CAS CSCD 2016年第1期12-20,共9页
To enhance the yield potential of an elite indica rice cultivar,an introgression(BC_3-derived) line of IR64,YTH288,was developed using a new-plant-type cultivar,IR66215-44-2-3,as a donor parent.YTH288 has agronomicall... To enhance the yield potential of an elite indica rice cultivar,an introgression(BC_3-derived) line of IR64,YTH288,was developed using a new-plant-type cultivar,IR66215-44-2-3,as a donor parent.YTH288 has agronomically valuable characteristics such as large panicles,few unproductive tillers,and large leaves inherited from NPT.To identify the genetic basis of these traits,we used 167 F_2 plants derived from a cross between IR64 and YTH288 to conduct QTL analysis for five agronomic traits:days to heading(DTH),culm length(CL),flag leaf length(FLL),flag leaf width(FLW),and filled spikelet number per panicle(FSN).Six putative QTL were detected:four on chromosome4(for CL,FLL,FLW,and FSN) and two on chromosome 2(for DTH and FLL).All QTL with the IR66215-44-2-3 allele,except that for FLL on chromosome 2,had positive effects on each trait.To confirm the effects of these putative QTL,we developed NILs with the IR64 genetic background by marker-assisted selection.We observed significant differences in several agronomic traits between IR64 and NILs that carried these QTL on chromosomes2 and 4.Additionally,four IR64-NILs carrying chromosomal segments derived from different NPT varieties on the long arm of chromosome 4 exhibited similar pleiotropic To enhance the yield potential of an elite indica rice cultivar, an introgression(BC3-derived) line of IR64, YTH288, was developed using a new-plant-type cultivar,IR66215-44-2-3, as a donor parent. YTH288 has agronomically valuable characteristics such as large panicles, few unproductive tillers, and large leaves inherited from NPT.To identify the genetic basis of these traits, we used 167 F2 plants derived from a cross between IR64 and YTH288 to conduct QTL analysis for five agronomic traits: days to heading(DTH), culm length(CL), flag leaf length(FLL), flag leaf width(FLW), and filled spikelet number per panicle(FSN). Six putative QTL were detected: four on chromosome4(for CL, FLL, FLW, and FSN) and two on chromosome 2(for DTH and FLL). All QTL with the IR66215-44-2-3 allele, except that for FLL on chromosome 2, had positive effects on each trait. To confirm the effects of these putative QTL, we developed NILs with the IR64 genetic background by marker-assisted selection. We observed significant differences in several agronomic traits between IR64 and NILs that carried these QTL on chromosomes2 and 4. Additionally, four IR64-NILs carrying chromosomal segments derived from different NPT varieties on the long arm of chromosome 4 exhibited similar pleiotropiceffects for unique agronomic traits. These NILs can be used as research materials for studying each trait and as breeding materials for yield improvement of indica rice cultivars. 展开更多
关键词 Agronomic traits Quantitative trait loci Near-isogenic lines New-plant-type RICE variety PLEIOTROPIC effect
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Activation of Sonic Hedgehog Signaling Pathway in S-type Neuroblastoma Cell Lines
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作者 周昱男 戴若连 +4 位作者 毛玲 夏远鹏 姚玉芳 杨雪 胡波 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2010年第3期271-277,共7页
The effects of Sonic hedgehog(Shh) signaling pathway activation on S-type neuroblastoma(NB) cell lines and its role in NB tumorigenesis were investigated.Immunohistochemistry was used to detect the expression of Shh p... The effects of Sonic hedgehog(Shh) signaling pathway activation on S-type neuroblastoma(NB) cell lines and its role in NB tumorigenesis were investigated.Immunohistochemistry was used to detect the expression of Shh pathway components— Patched1(PTCH1) and Gli1 in 40 human primary NB samples.Western blotting and RT-PCR were used to examine the protein expression and mRNA levels of PTCH1 and Gli1 in three kinds of S-type NB cell lines(SK-N-AS,SK-N-SH and SHEP1),respectively.Exogenous Shh was administrated to activate Shh signaling pathway while cyclopamine was used as a selective antagonist of Shh pathway.S-type NB cell lines were treated with different concentrations of Shh or/and cyclopamine for different durations.Cell viability was measured by using MTT method.Apoptosis rate and cell cycle were assayed by flow cytometry.The xenograft experiments were used to evaluate the role of Shh pathway in tumor growth in immunodeficient mice.High-level expression of PTCH1 and Gli1 was detected in both NB samples and S-type NB cell lines.Cyclopamine decreased the survival rate of the three cell lines while Shh increased it,and the inhibition effects of cyclopamine could be partially reversed by shh pre-treatment.Cyclopamine induced the cell apoptosis and the cell cycle arrest in G0/G1 phase,while Shh induced the reverse effects and could partially prevent effects of cyclopamine.Cyclopamine could also inhibit the growth of NB in vivo.Our studies revealed that activation of the Shh pathway is important for survival and proliferation of S-type NB cells in vivo and in vitro through affecting cell apoptosis and cell cycle,suggesting a new therapeutic approach to NB. 展开更多
关键词 S-type neuroblastoma cell lines Sonic hedgehog signaling pathway CYCLOPAMINE
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Riemann Boundary Value Problem of Non-Normal Type on the Infinite Straight Line 被引量:2
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作者 Lixia Cao 《Applied Mathematics》 2013年第8期1226-1230,共5页
Various kinds of Riemann boundary value problems (BVPs) for analytic functions on closed curves or on open arc, doubly periodic Riemann BVPs, doubly quasi-periodic Riemann BVPs, and BVPs for polyanalytic functions hav... Various kinds of Riemann boundary value problems (BVPs) for analytic functions on closed curves or on open arc, doubly periodic Riemann BVPs, doubly quasi-periodic Riemann BVPs, and BVPs for polyanalytic functions have been widely investigated in [1-8]. The main ap- proach is to use the decomposition of polyanalytic functions and their generalization to transform the boundary value problems to their corresponding boundary value problems for analytic functions. Recently, inverse Riemann BVPs for generalized analytic functions or bianalytic functions have been investigated in [9-12]. In this paper, we consider a kind of Riemann BVP of non-normal type on the infinite straight line and discuss the solvable conditions and the general solution for it. 展开更多
关键词 Non-Normal type RIEMANN BOUNDARY VALUE Problem The INFINITE STRAIGHT line
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Meshless Method of Lines for Numerical Solution of Kawahara Type Equations
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作者 Nagina Bibi Syed Ikram Abbas Tirmizi Sirajul Haq 《Applied Mathematics》 2011年第5期608-618,共11页
In this work, an algorithm based on method of lines coupled with radial basis functions namely meshless method of lines (MMOL) is presented for the numerical solution of Kawahara, modified Kawahara and KdV Kawahara eq... In this work, an algorithm based on method of lines coupled with radial basis functions namely meshless method of lines (MMOL) is presented for the numerical solution of Kawahara, modified Kawahara and KdV Kawahara equations. The motion of a single solitary wave, interaction of two and three solitons and the phenomena of wave generation is discussed. The results are compared with the exact solution and with the results in the relevant literature to show the efficiency of the method. 展开更多
关键词 Kawahara type EQUATIONS MESHLESS Method of lines (MMOL) RADIAL Basis Functions (Rbfs)
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电磁学中标量的方向问题
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作者 付全红 胡亮 +2 位作者 郑建邦 樊元成 张富利 《物理通报》 2026年第1期140-141,共2页
电磁学中标量的方向问题是一个值得关注的问题,尽管已有一些文献对该问题做了一些讨论,但都不够深入或准确.本文从这些标量的定义式出发,讨论了标量方向问题的起源及标量参考方向的本质和描述.
关键词 标量 方向 第二类线积分 第二类面积分
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Numerical simulation of the temperature field within new type of monolayer freezing-shaft lining 被引量:4
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作者 CHEN, Xiaoxiang YANG, Weihao 《Mining Science and Technology》 EI CAS 2010年第2期198-203,共6页
Numerical simulation was used to estimate the temperature field within a poured concrete,mono-layer freezing-shaft lining.The affects from various factors were investigated.The maximum temperature within the lining in... Numerical simulation was used to estimate the temperature field within a poured concrete,mono-layer freezing-shaft lining.The affects from various factors were investigated.The maximum temperature within the lining increases as the lining thickness increases,decreases as the soil-side wall temperature decreases,decreases as the air temperature inside the shaft decreases and decreases as the air velocity inside the shaft increases.The compression speed of an insulating foam layer affects the maximum temperature difference between the interior and the sidewalls.The maximum temperature difference between the interior and the sidewalls approaches or exceeds the maximum allowable for the curing of poured concrete structures.Attention should be paid to the question of the lining cracking during the curing period.The temperature gradient in the vertical direction may be minimized by preventing air contact against the steel connection board supporting the base of the freshly poured section. 展开更多
关键词 new type MONOLAYER freezing shaft lining temperature field numerical simulation
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Study on a cold-cathode H^- PIG-type ion source 被引量:4
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作者 LONG Jidong YANG Zhen +2 位作者 DONG Pan HE Xiaozhong ZHANG Kaizhi 《Nuclear Science and Techniques》 SCIE CAS CSCD 2013年第4期1-4,共4页
A cold-cathode Penning Ion Gauge(PIG) type ion source as the internal ion source of an 11 MeV cyclotron is designed and tested at Institute of Fluid Physics.The design considerations and some testings are presented.Ex... A cold-cathode Penning Ion Gauge(PIG) type ion source as the internal ion source of an 11 MeV cyclotron is designed and tested at Institute of Fluid Physics.The design considerations and some testings are presented.Experimental results of Balmer-line-Emission show that the discharge characteristic,which is mainly determined by gas-flow rate,is not very sensitive to arc current and magnetic field in the operation ranges of the cyclotron.The arc power decreases and ascends while the gas-flow rate goes up from 0.5 SCCM to 20 SCCM.By improving the sealing design and reducing the machine tolerance of the source,the minimum power consumption reduces from 9 SCCM to 4 SCCM,thus having better energy efficiency and benefiting for the pumping system.Preliminary DC extractions show that H–microampere current ranges from several tens to hundreds under different operation conditions.Some problems during the experiments and future plan are discussed in the end. 展开更多
关键词 离子源 冷阴极 回旋加速器 G型 密封设计 实验过程 物理研究所 放电特性
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On-line Popularity Monitoring Method Based on Bloom Filters and Hash tables for Differentiated Traffic 被引量:4
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作者 ZHANG Guo ZHANG Jianhui +1 位作者 WANG Binqiang ZHANG Zhen 《China Communications》 SCIE CSCD 2016年第S1期72-86,共15页
Towards line speed and accurateness on-line content popularity monitoring on Content Centric Networking(CCN) routers, we propose a three-stage scheme based on Bloom filters and hash tables for differentiated traffic. ... Towards line speed and accurateness on-line content popularity monitoring on Content Centric Networking(CCN) routers, we propose a three-stage scheme based on Bloom filters and hash tables for differentiated traffic. At the first stage, we decide whether to deliver the content to the next stage depending on traffic types. The second stage consisting of Standard Bloom filters(SBF) and Counting Bloom filters(CBF) identifies the popular content. Meanwhile, a scalable sliding time window based monitoring scheme for different traffic types is proposed to implement frequent and real-time updates by the change of popularities. Hash tables according with sliding window are used to record the popularity at the third stage. Simulation results reveal that this method reaches a 40 Gbps processing speed at lower error probability with less memory, and it is more sensitive to the change of popularity. Additionally, the architecture which can be implemented in CCN router is flexible and scalable. 展开更多
关键词 CCN line speed TRAFFIC type BLOOM filters HASH tables POPULARITY monitoring
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基于联络线传输功率可行域的多类型储能优化配置策略
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作者 胡浩 赵雪楠 +3 位作者 尚国政 郑子萱 徐正阳 李杰 《储能科学与技术》 北大核心 2026年第1期243-254,共12页
受外送通道传输容量及区域电网内部多维安全边界的限制,大规模新能源面临外送通道阻塞的严峻挑战。针对阻塞管理过程中联络线传输极限约束难以精确表征其传输能力及单一类型储能调节能力有限的问题,提出一种基于联络线传输功率可行域的... 受外送通道传输容量及区域电网内部多维安全边界的限制,大规模新能源面临外送通道阻塞的严峻挑战。针对阻塞管理过程中联络线传输极限约束难以精确表征其传输能力及单一类型储能调节能力有限的问题,提出一种基于联络线传输功率可行域的多类型储能优化配置策略。首先,计及区域电网多维安全边界构建电网安全稳定运行空间,并基于顶点搜索法将其投影至联络线传输功率空间以刻画传输功率可行域;基于此,结合多类型储能的差异化互补调节潜力,本研究建立以综合经济收益最优为目标的多类型储能优化配置模型,利用混合整数线性规划(MILP)求解多类型储能最优配置方案并获取最优联络线外送功率曲线;最后,基于我国北方某地区实际运行数据开展算例分析,验证所提多类型储能优化配置策略的可行性与有效性。结果表明,所提策略可经济有效地提高外送通道利用率、缓解弃风弃光现象,并降低电网线路阻塞风险。 展开更多
关键词 联络线传输功率可行域 输电阻塞 多类型储能优化配置 混合整数规划
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ECMWF降水相态预报产品(PTYPE)应用和检验 被引量:11
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作者 董全 胡宁 宗志平 《气象》 CSCD 北大核心 2020年第9期1210-1221,共12页
运用我国2016-2018年三个冬半年(10月至次年3月)地面2515个站的天气现象观测资料,对ECMWF(European Centre for Medium-Range Weather Forecasts)的降水相态预报产品(PTYPE)(分为雨、雨夹雪、雪和冻雨四类)进行了系统性的检验评估,包括... 运用我国2016-2018年三个冬半年(10月至次年3月)地面2515个站的天气现象观测资料,对ECMWF(European Centre for Medium-Range Weather Forecasts)的降水相态预报产品(PTYPE)(分为雨、雨夹雪、雪和冻雨四类)进行了系统性的检验评估,包括细网格确定性模式预报产品和集合预报系统概率预报产品。结果显示,ECMWF的确定性预报产品对四类降水相态的正确率普遍达到90%以上,对降雨和降雪的TS评分也较高,冻雨次之,雨夹雪的TS评分较低,预报能力有限。确定性模式对我国雨雪分界线的预报,普遍存在短期位置略偏南、中期随时效延长越来越偏北的误差特点,且对雨夹雪的预报范围明显偏小,对冻雨的预报范围明显偏大。集合预报系统从概率的角度一定程度上弥补了确定性模式的上述误差。对概率预报的检验结果显示,集合预报系统降雨概率普遍偏低,降雪概率短期偏高、中期偏低,而雨夹雪和冻雨概率普遍偏低,但是都有一定的预报技巧。集合预报系统相对于确定性模式的优势,降雨体现在较小花费损失比事件的预报上,降雪体现在较大花费损失比事件的预报上。对雨夹雪和冻雨,相对于确定性模式,集合预报系统体现出了显著的优势,尤其是冻雨,集合预报系统的优势更加明显。 展开更多
关键词 ECMWF 降水相态预报产品(Ptype) 雨雪分界线 检验
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Experimental Study on the Flow Characteristics of ¬-Type Groyne
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作者 Joongu Kang Hongkoo Yeo 《Engineering(科研)》 2011年第10期1002-1011,共10页
A hydraulic model test for ¬-type groynes (with “¬” shape) was conducted to analyze the flow characteristics around these groynes. The results of the model tests are expected to be used as fundamental information ... A hydraulic model test for ¬-type groynes (with “¬” shape) was conducted to analyze the flow characteristics around these groynes. The results of the model tests are expected to be used as fundamental information in designing the ¬-type groyne constructed in the field. Main hydraulic factors such as velocity and thalweg line changes in the main channel and separation area were analyzed in this study. The thalweg line is a stream line where the maximum velocity occurs, whereas the separation area is the boundary between the main flow and the recirculation zone. Model tests with 5 different arm lengths of the ¬-type groynes were conducted by changing the velocity. The LSPIV (Large-Scale Particle Image Velocimetry) technique was used to measure and analyze flow variation around the ¬-type groynes. The velocity in the main channel measured to be increased by 1.5 times. The velocity variation on groyne arm length is little. The width of the thalweg lines (TCL) was changed to 55 - 57% of the channel width. The Froude number did not affect the thalweg line (TCL) and separation line (Sh) changes, however. 展开更多
关键词 ¬-type type Groyne THALWEG line SEPARATION line Recirculation ZONE LSPIV
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Selection of Homozygous Cotton Lines Transformed with Two Insect-Resistant Genes 被引量:1
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作者 WUJia-he TIANYing-chuan +6 位作者 LUOXiao-li GUOHong-nian SHIYue-jin CHENXiao-ying: JIAYan-tao XIAOJuan-li ZHANGXian-long 《Agricultural Sciences in China》 CAS CSCD 2003年第9期950-956,共7页
A plant expression vector containing a chimeric Bt29K gene coding for the activated Cry1Ac protein and the arrowhead proteinase inhibitior gene API B were introduced into the cotton cultivar Jihe321 mediated ... A plant expression vector containing a chimeric Bt29K gene coding for the activated Cry1Ac protein and the arrowhead proteinase inhibitior gene API B were introduced into the cotton cultivar Jihe321 mediated by Agrobactertium tumefaciens. Based on the results of kanamycin resistant testing, PCR detection for both foreign genes and insect bioassay using Heliethis armigera , nine transgenic homozygous cotton lines with insect resistance of more than 90% and better agronomic traits were bred through six generations from the original transgenic plants. Results from insect bioassay and sequence analysis of the PCR products of plants from some homozygous lines indicated that the chimeric Bt29K gene was stably inherited in these transgenic cotton lines. The main agronomic characters of these homozygous cotton lines, such as boll productivity and fibre strength, were better than that of the original cotton cv. Jihe321. 展开更多
关键词 COTTON Two types of insect resistant genes Transgenic homozygous lines Jihe321 cotton bollworm
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STUDY ON THE LOG PRODUCTION LINE IN LOG YARD
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作者 Pan Delu Wang Jingxin Northeast Forestry University 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1991年第2期77-82,共6页
The article deals with the prduction lines in log yard by investigating the utilizationof machines in forest areas,presents the methods and rules of differentiating the log productionlines and also summarizes the form... The article deals with the prduction lines in log yard by investigating the utilizationof machines in forest areas,presents the methods and rules of differentiating the log productionlines and also summarizes the formation and development of three kinds of log production lines innortbeast forest areas of China.It gives different combination types of log production lines andtheir applications, so it is significant for us to evaluate and standardize the log Production lines. 展开更多
关键词 LOG production line The machines combining types LOG YARD FOREST LOGGING operations
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烟用内衬纸关键性指标分析及其影响机制初步研究 被引量:2
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作者 贾伟萍 刘文婷 +4 位作者 黄轲 李陈巧 王波 王鹏 安俊健 《包装工程》 北大核心 2025年第5期121-128,共8页
目的建立烟用内衬纸关键性指标的专用检测方法,初步分析相关指标的影响因素,为其具体应用提供理论依据。方法采用相应的研究方法及国家标准对烟用内衬纸的部分关键性指标(透湿性和成型度)及微观特性指标(厚度、纸张表面pH值和纤维组成)... 目的建立烟用内衬纸关键性指标的专用检测方法,初步分析相关指标的影响因素,为其具体应用提供理论依据。方法采用相应的研究方法及国家标准对烟用内衬纸的部分关键性指标(透湿性和成型度)及微观特性指标(厚度、纸张表面pH值和纤维组成)进行检测,并进一步分析相应微观特性指标对关键性指标的影响。结果采用研究方法测定不同类型烟用内衬纸的透湿性和成型度,发现复合内衬纸的透湿量和成型度均较低,透湿量为0.5544~2.046 g/(m2·24 h),成型度为22°~26°,转移镀铝内衬纸和无铝内衬纸的透湿性和成型度相差不大;内衬纸的微观特性对样品的成型度有一定影响,一般随着厚度的增加内衬纸的成型度随之增加,阔叶木浆用量增加,成型度有降低的趋势。结论建立烟用内衬纸透湿性和成型度的有效检测方法,分析微观特性参数对宏观特性的影响,具有一定的理论和应用价值。 展开更多
关键词 烟用内衬纸 透湿性 成型度 纤维种类
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A New Type of Double-Lumen Catheter to Replace Current One in RCA 被引量:1
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作者 Yingfeng Xue Zhenguo Yu 《International Journal of Clinical Medicine》 2016年第9期620-627,共8页
Objective: To replace the peripheral venous puncture for blood sampling with taking blood samples extracorporally from arterial line before predilution during RCA-CRRT performed. Methods: A new type of double-lumen fe... Objective: To replace the peripheral venous puncture for blood sampling with taking blood samples extracorporally from arterial line before predilution during RCA-CRRT performed. Methods: A new type of double-lumen femoral catheter was used instead of the current tubes. The new type of double-lumen tube had a greater distance from the inner venous ports to the inner arterial ports than current tubes. The minimum distance from the venous port to the arterial port was greatly lengthened. Replacement solution contained citrate, zero Ca<sup>2+</sup>, zero bicarbonate, low Na<sup>+</sup>. Blood samples were synchronously collected from the arterial line before the infusion of citrate replacement fluid and from the peripheral vein. The iCa concentration data of two groups were analyzed to observe the difference between iCa concentration levels in the arterial line and in peripheral vein;the anticoagulant effect of RCA and possible complications were observed, such as bleeding, clottings and hypocalcaemia. Results: 28 times of RCA-CRRT were performed on17 AKI and CRF patients with active bleeding or at the high risk of bleeding;336 blood samples were collected. Statistics showed that the difference of iCa concentration between arterial line group and the peripheral vein group was not significant (P = 0.9), there is a high degree of similarity between the iCa concentration of arterial line blood and the peripheral venous blood. None of the patients developed citrate toxicity or metabolic alkalosis. None induced bleeding, or bleeding aggravated. No obvious clotting occurred. Systemic calcium concentration was achieved in the ideal range. Conclusion: In clinical practice, the data of iCa concentration from arterial line can be used to replace that from peripheral vein when the new type of double-lumen femoral catheter is placed in femoral vein. RCA-CRRT therapy is safe and effective. 展开更多
关键词 RCA-CRRT Ionized Calcium Arterial line Peripheral Vein New type of Double-Lumen Femoral Catheter
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基于悬链线方程的近海漂浮式光伏汇集动态缆线型设计方法
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作者 王春杰 俞子龙 +2 位作者 孔祥玉 俞露杰 付强 《太阳能学报》 北大核心 2025年第8期387-395,共9页
结合近海浅水环境下水深变化明显及动态缆抗载荷能力需求,提出一种漂浮式光伏汇集动态缆线型设计方法,基于悬链线方程建立缓波式动态缆线型模型,结合Orcaflex软件构建有限元模型设计动态缆线型初步方案,考虑浮体偏移情况,在满足约束条... 结合近海浅水环境下水深变化明显及动态缆抗载荷能力需求,提出一种漂浮式光伏汇集动态缆线型设计方法,基于悬链线方程建立缓波式动态缆线型模型,结合Orcaflex软件构建有限元模型设计动态缆线型初步方案,考虑浮体偏移情况,在满足约束条件下以缆长最短为优化目标,采用改进模拟退火算法对线型初步方案进行优化寻找全局最优解。结合某海域实际工程数据分析,分析在动态缆定长时首端连接角度对线型的影响,并利用Orcaflex软件验证优化后动态缆线型方案的可靠性与所提方法的可行性。 展开更多
关键词 漂浮式光伏 动态缆 悬链线理论 缓波式线型 模拟退火算法 曲率半径
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线路类型及射流倾角对下击暴流作用下高速列车运行安全性影响研究
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作者 李鹏 李波 +2 位作者 田玉基 杨庆山 李若琦 《工程力学》 北大核心 2025年第8期108-118,共11页
随着我国铁路线网密度的不断增大和下击暴流等极端天气发生频率的不断增加,高速列车受到下击暴流袭击的风险不断提升,对下击暴流作用下高速列车运行安全性进行评估尤为重要。利用物理模拟器对下击暴流作用下的高速列车进行刚性模型测压... 随着我国铁路线网密度的不断增大和下击暴流等极端天气发生频率的不断增加,高速列车受到下击暴流袭击的风险不断提升,对下击暴流作用下高速列车运行安全性进行评估尤为重要。利用物理模拟器对下击暴流作用下的高速列车进行刚性模型测压试验,研究线路类型和射流倾角对下击暴流作用下高速列车表面风压分布特性及车体风力特性的影响,选取脱轨系数、轮重减载率、轮轴横向力和轮轨垂向力为安全性指标对列车运行安全性进行评估。结果表明:随着径向距离的增加,除列车右面(迎风面)风压系数先增大后减小且保持压力外,其余各面风压系数急剧减小且由压力转变为风吸力,在相对径向距离r/D_(jet)=1.0附近时表现出和横风作用下类似的风压分布;列车位于路堤及高架桥时侧向力系数CFx、升力系数CFz及侧滚力矩系数C_(Mx)峰值均大于平地,但线路类型对各风力系数峰值发生的径向位置基本无影响;随着射流倾角的增大,侧向力系数CFx和侧滚力矩系数C_(Mx)峰值均逐渐减小,且峰值出现的径向位置逐渐远离射流中心;列车位于高架桥时安全运行速度域最小,其次为平地,路堤最大,即列车在高架桥上运行时最危险;射流倾角的存在可使相同下击暴流风速下列车的允许运行速度提升,且当列车位于倾斜下击暴流背侧时的运行允许车速大于前侧。 展开更多
关键词 下击暴流 物理模拟 高速列车 气动特性 运行安全性 线路类型 射流倾角
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A simple scheme to generate χ-type four-charge entangled states in circuit QED 被引量:1
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作者 高贵龙 宋付权 +4 位作者 黄寿胜 王辉 袁先漳 王明锋 姜年权 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第4期331-335,共5页
We propose a simple scheme to generate x-type four-charge entangled states by using SQUID-based charge qubits capacitively coupled to a transmission line resonator (TLR). The coupling between the superconducting qub... We propose a simple scheme to generate x-type four-charge entangled states by using SQUID-based charge qubits capacitively coupled to a transmission line resonator (TLR). The coupling between the superconducting qubit and the TLR can be effectively controlled by properly adjusting the control parameters of the charge qubit. The experimental feasibility of our scheme is also shown. 展开更多
关键词 x-type entangled state superconducting quantum interference device transmission line resonator superconducting charge qubit
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