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基于Gaussian算法的高压直流平抗瓦斯非线性耦合动态特性精细化建模 被引量:1
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作者 郑伟杰 《中国电机工程学报》 EI CSCD 北大核心 2018年第2期637-643,共7页
随着近几年来大量高压直流输电工程接入交流系统,给交直流混联电网带来重要影响,直流系统的运行状况,尤其是其控制保护系统的性能,已成为影响交直流混联电网安全稳定的重要因素。系统故障引发平波电抗器瓦斯保护误动作是导致直流系统闭... 随着近几年来大量高压直流输电工程接入交流系统,给交直流混联电网带来重要影响,直流系统的运行状况,尤其是其控制保护系统的性能,已成为影响交直流混联电网安全稳定的重要因素。系统故障引发平波电抗器瓦斯保护误动作是导致直流系统闭锁的重要非电气量因素之一,该文详细研究分析了平抗瓦斯的设备原理和特点,采用Gaussian回归算法对平抗瓦斯机械振动与冲击电流的非线性耦合特性进行精细化模拟和解耦,且与电磁暂态算法相兼容,并基于国网仿真中心华东电网电力系统全数字实时仿真装置(advanced digital power system simulator,ADPSS)纯电磁暂态实际工程控保算例进行交直流电网纯电磁仿真,可以详细描述交直流电网故障冲击电流等电气量动态变化对平抗瓦斯机械振动加速度非电气量的非线性快速响应动态特性,为实际工程中多次发生的平抗瓦斯误动导致直流闭锁的事故分析和故障重演、预防及设备改进提供关键技术手段,对进一步提高直流实用化工程仿真的多维度精度具有重要现实意义,并为其他非线性电气相关设备的详细建模提供思路。 展开更多
关键词 高压直流闭锁 换相失败 平抗瓦斯保护 非电气量 非线性动态特性
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“平抗1号”金叶女贞新品种的选育 被引量:1
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作者 胡清坡 刘宏敏 +1 位作者 张山林 梁建 《安徽农学通报》 2009年第16期44-45,59,共3页
":平抗1号"金叶女贞这一抗病优良品种的成功选育,从根本上解决了金叶女贞大面积感染叶斑病的问题,节约了生产管理成本,提高了金叶女贞的观赏价值。通过3个试验点3a的试验表明,"平抗1号"金叶女贞平均叶长:56.3mm,叶... ":平抗1号"金叶女贞这一抗病优良品种的成功选育,从根本上解决了金叶女贞大面积感染叶斑病的问题,节约了生产管理成本,提高了金叶女贞的观赏价值。通过3个试验点3a的试验表明,"平抗1号"金叶女贞平均叶长:56.3mm,叶宽:28.5mm,叶厚:0.39mm,长宽比为1.98:1。与普通金叶女贞相比,其叶形差异不大,但叶片较厚。"平抗1号"金叶女贞的平均株高为82.2cm,分枝数为4,地径为11.2mm,与普通金叶女贞相比,其生长势明显大于普通金叶女贞。平抗1号"金叶女贞对叶斑病的感病株率为0%、感病叶率为0%、落叶率为3.86%,对金叶女贞叶斑病具有极强的抗性,从显微观察和DNA分析验证了平抗1号金叶女贞组织结构和遗传物质的特异性。 展开更多
关键词 平抗1号 金叶女贞 新品种 选育
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“平抗1号”金叶女贞高效栽培技术及种植效益分析 被引量:1
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作者 胡清坡 周威 +1 位作者 杜国平 梁健 《安徽农学通报》 2009年第18期129-130,共2页
"平抗1号"金叶女贞是平顶山市园林试验场选育的优良抗病新品种,其突出特点是对叶斑病抗性极高,生产栽培中几乎不用药,生长速度极快,适应性广,对土壤要求不严格,容易培育,管理粗放。繁育方法主要是扦插法,分为嫩枝扦插和硬技... "平抗1号"金叶女贞是平顶山市园林试验场选育的优良抗病新品种,其突出特点是对叶斑病抗性极高,生产栽培中几乎不用药,生长速度极快,适应性广,对土壤要求不严格,容易培育,管理粗放。繁育方法主要是扦插法,分为嫩枝扦插和硬技扦插。平抗1号是目前替代金叶女贞原品种进行园林造景的有色地被植物,极具发展前景。 展开更多
关键词 平抗1号 金叶女贞 品种特性 栽培技术 园林绿化
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云广±800kV直流输电工程直流等效干扰电流限值研究 被引量:4
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作者 黄莹 孙帮新 +1 位作者 黎小林 饶宏 《南方电网技术》 2007年第1期32-36,共5页
从直流滤波器性能的角度分析了影响云广±800kV直流输电工程等效干扰电流的因素,包括换流器对地杂散电容、平抗布置方式、直流滤波器型式等因素对直流滤波器性能的影响。然后参照目前直流输电工程的发展趋势,提出云广±800kVUH... 从直流滤波器性能的角度分析了影响云广±800kV直流输电工程等效干扰电流的因素,包括换流器对地杂散电容、平抗布置方式、直流滤波器型式等因素对直流滤波器性能的影响。然后参照目前直流输电工程的发展趋势,提出云广±800kVUHVDC输电工程合理的直流谐波指标。 展开更多
关键词 等效干扰电流 直流滤波器 对地杂散电容 平抗布置方式
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Harmonic Impedance Modeling and Oscillation Analysis of Modular Multilevel Converter
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作者 Wang Yuhong Chen Wensheng +2 位作者 Gao Shilin Liao Jianquan Cheng Yangfan 《系统仿真学报》 CAS CSCD 北大核心 2024年第12期2755-2770,共16页
To facilitate rapid analysis of the oscillation stability mechanism in modular multilevel converter-based high voltage direct current(MMC-HVDC)systems and streamline the simulation process for determining MMC impedanc... To facilitate rapid analysis of the oscillation stability mechanism in modular multilevel converter-based high voltage direct current(MMC-HVDC)systems and streamline the simulation process for determining MMC impedance characteristics,a simplified mathematical simulation model for MMC closed-loop impedance is developed using the harmonic state space method.This model considers various control strategies and includes both AC-side and DC-side impedance models.By applying a Nyquist criterion-based impedance analysis method,the stability mechanisms on the AC and DC sides of the MMC are examined.In addition,a data-driven oscillation stability analysis method is also proposed,leveraging a global sensitivity algorithm based on fast model results to identify key parameters influencing MMC oscillation stability.Based on sensitivity analysis results,a parameter adjustment strategy for oscillation suppression is proposed.The simulation results from the MATLAB/Simulinkbased MMC model validate the effectiveness of the proposed method. 展开更多
关键词 modular multilevel converter impedance modeling harmonic state space global sensitivity impedance analysis
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Experimental validation of horizontal joints in an innovative totally precast shear wall system 被引量:11
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作者 孙建 邱洪兴 陆波 《Journal of Southeast University(English Edition)》 EI CAS 2015年第1期124-129,共6页
To investigate the feasibility and seismic performance of the horizontal joints in an innovative precast shear wall system, two test walls were fabricated, and the monotonic and cyclic loading tests were performed on ... To investigate the feasibility and seismic performance of the horizontal joints in an innovative precast shear wall system, two test walls were fabricated, and the monotonic and cyclic loading tests were performed on the two test walls, respectively. Then, the lateral load-top displacement curves, load beating capacity, ductility, lateral stiffness, strains of steel bars, strain distribution on the connecting steel frame (CSF), and relative slippages between the CSF and embedded limbic steel frame (ELSF) were discussed in detail. The test results show that the load bearing capacity and ductility of the test wall are both favorable with a displacement ductility factor of more than 3.7. The normal and shear stresses in the CSF except for the compression end are far smaller than the yield stresses throughout the test procedure. Certain slippages of about 1.13 mm occurs between the CSF and ELSF on the compression side of the test wall, while almost no slippages occurs on the tension side. The seismic performance of the test wall is favorable and the new-type scheme of the horizontal joints is both feasible and reliable. 展开更多
关键词 precast shear wall horizontal joints seismic performance FEASIBILITY
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Ca^(2+)-homeostasis Differs Between Plant Species with Different Cold-tolerance at 4 ℃ Chilling 被引量:14
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作者 简令成 孙龙华 +3 位作者 李积宏 王红 孙德兰 Paul HLI 《Acta Botanica Sinica》 CSCD 2000年第4期358-366,共9页
A comparative study was carried out on the EM_cytochemical localization of calcium and Ca 2+ _ATPase activity in the suspension_cultured cells between the chilling_sensitive maize ( Zea mays L. cv. Black Mexica... A comparative study was carried out on the EM_cytochemical localization of calcium and Ca 2+ _ATPase activity in the suspension_cultured cells between the chilling_sensitive maize ( Zea mays L. cv. Black Mexican Sweet) and chilling_insensitive Trititrigia ( Triticum sect. Trititrigia mackey) at 4 ℃ chilling. When maize and Tyititrigia cells were cultured at 26 ℃, electron microscopic observations revealed that the electron_dense calcium antimonate deposits, an indication of the calcium localization, were localized mainly in the vacuoles, and few was found in the cytosol and nuclei. The electron_dense cerium phosphate deposits, an indication of Ca 2+ _ATPase activity, were abundantly distributed on the plasma membrane (PM). When the cells from both species were cultured at 4 ℃ for 1 and 3 h, an elevation of Ca 2+ level in the cytosol and nuclei was observed, whereas the cerium phosphate deposits on the PM showed no quantitative difference from those of the 26 ℃_cultured cells, indicating that the enzymatic activities were not altered during these chilling periods. However, there was a distinct difference in the dynamics of the Ca 2+ distribution and the PM Ca 2+ _ATPase activity between maize and Trititrigia when chilled at 4 ℃ for 12, 24 and 72 h. In maize cells, a large number of Ca 2+ deposits still existed in the cytosol and nuclei, and the PM Ca 2+ _ATPase became less and less active, and even inactive at all. In Trititrigia cells, the increased cytosolic and nuclear Ca 2+ ions decreased after 12 h chilling. By chilling up to 24 and 72 h, the intracellular Ca 2+ concentration had been restored to a similar low level as those of the warm temperature_cultured cells, while the activity of the PM Ca 2+ _ATPase maintained high. The transient cytosolic and nuclear Ca 2+ increase and the activities of PM Ca 2+ _ATPase during chilling are discussed in relation to plant cold hardiness. 展开更多
关键词 Ca 2+ plasmalemma Ca 2+ _ATPase Ca 2+ _homeostasis plant cold hardiness maize Trititrigia
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Influence of superplasticizers on the early-age crack resistance of concrete 被引量:1
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作者 钱春香 陆旺杰 +3 位作者 何智海 范凌志 曲军 郭景强 《Journal of Southeast University(English Edition)》 EI CAS 2012年第1期41-45,共5页
In order to improve the early-age cracking resistance of concrete, different types of superplasticizers are used. Two types of polycarboxlic salt/acid superplasticizers and one retarding naphthalene superplasticizer a... In order to improve the early-age cracking resistance of concrete, different types of superplasticizers are used. Two types of polycarboxlic salt/acid superplasticizers and one retarding naphthalene superplasticizer are selected to investigate the influence of superplasticizers on the early-age cracking resistance of the concrete by using the slab test and the temperature-stress test. The results show that the polycarboxlic salt/acid superplasticizer cannot always improve the cracking resistance capacity of the concrete compared with the naphthalene superplasticizer, which is related to the chemical structure of the polycarboxlic salt/acid superplasticizer. High plastic tensile strength and dynamic elastic modulus at the early stage are beneficial to avoid cracking, and low hydration heat is also helpful. The evolutions of the drying shrilakage stress and the hydration heat temperature stress varying with time can be comprehensively evaluated by means of the slab test and the temperature stress test. 展开更多
关键词 SUPERPLASTICIZER crack resistance slab testmethod temperature-stress test method
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直流抗震干式平波电抗器安装技术——以裕隆换流站平波电抗器安装为例
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作者 罗肖 《中文科技期刊数据库(全文版)工程技术》 2016年第11期169-169,共1页
以西昌裕隆换流站平波电抗器安装为例,简要论述平抗安装在在作业规划和技术创新等方面的操作经验。
关键词 平抗 过程控制 消声器 线圈本体
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A High Linearity,13bit Pipelined CMOS ADC 被引量:1
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作者 李福乐 段静波 王志华 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第3期497-501,共5页
A 13bit,pipelined analog-to-digital converter (ADC) designed to achieve high linearity is described. The high linearity is realized by using the passive capacitor error-averaging technique to calibrate the capacitor... A 13bit,pipelined analog-to-digital converter (ADC) designed to achieve high linearity is described. The high linearity is realized by using the passive capacitor error-averaging technique to calibrate the capacitor mismatch error, a gain-boosting opamp to minimize the finite gain error and gain nonlinearity,a bootstrapping switch to reduce the switch on-resistor nonlinearity, and an anti-disturb design to reduce the noise from the digital supply. This ADC is implemented in 0.18μm CMOS technology and occupies a die area of 3.2mm^2 , including pads. Measured performance includes - 0.18/ 0.15LSB of differential nonlinearity, -0.35/0.5LSB of integral nonlinearity, 75.7dB of signal-to-noise plus distortion ratio (SNDR) and 90. 5 dBc of spurious-free dynamic range (SFDR) for 2.4MHz input at 2.5MS/s. At full speed conversion (5MS/s) and for the same 2.4MHz input, the measured SNDR and SFDR are 73.7dB and 83.9 dBc, respectively. The power dissipation including output pad drivers is 21mW at 2.5MS/s and 34mW at 5MS/s,both at 2.7V supply. 展开更多
关键词 analog-to-digital converter high linearity capacitor error-averaging GAIN-BOOSTING bootstrapping switch anti-disturb
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三国战争中的夷陵 被引量:1
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作者 宋杰 《史学集刊》 CSSCI 北大核心 2020年第6期20-32,62,共14页
夷陵是三国重镇与交战热点,原因在于它地扼峡口交通枢要,附近岭谷交错利于设防。曹操、刘备将夷陵与邻近各县并置临江、宜都郡,成为独立的军政建置。猇亭之战后,孙权设立西陵都督辖区。孙吴后期分宜都数县立建平郡,又将西陵、乐乡都督... 夷陵是三国重镇与交战热点,原因在于它地扼峡口交通枢要,附近岭谷交错利于设防。曹操、刘备将夷陵与邻近各县并置临江、宜都郡,成为独立的军政建置。猇亭之战后,孙权设立西陵都督辖区。孙吴后期分宜都数县立建平郡,又将西陵、乐乡都督辖区反复合并分离,下诏调离步阐而引起叛乱。蜀汉亡国后,西晋以峡江航道作为伐吴的主攻路线。孙皓忽视荆州西部的防务,致使王濬舟师顺利出峡攻占西陵,乘势东下灭亡吴国。 展开更多
关键词 夷陵 猇亭 西陵 宜都 建平 陆逊 陆抗 王濬
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Dishevelled interacts with p65 and acts as a repressor of NF-KB-mediated transcription 被引量:8
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作者 Ning Deng Yanger Ye Wei Wang Lin Li 《Cell Research》 SCIE CAS CSCD 2010年第10期1117-1127,共11页
Dishevelled (Dvl) is a highly conserved protein family that plays an important role in mediating Wnt signal- ing from membrane to cytoplasm. Recently we reported that Dvl also functions in the nucleus by stabilizing... Dishevelled (Dvl) is a highly conserved protein family that plays an important role in mediating Wnt signal- ing from membrane to cytoplasm. Recently we reported that Dvl also functions in the nucleus by stabilizing the β-catenin/TCFs transcriptional complex. Here we describe that Dvl may function as a repressor of NF-kB. Our data show that Dvl directly binds to p65 and their interaction occurs in the nucleus. Dvl expression inhibits p65-mediated or TNF-α-stimulated activation of the NF-KB dependent reporter. This action of Dvl, however, is not dependent on Wnt or its downstream effector β-catenin. Chromatin immunoprecipitation assay shows that recruitment of p65 to the promoters of NF-KB target genes is significantly enhanced when expression of Dvl is knocked down. Consistently, the expression level of a subset of NF-KB target genes is also increased after knock-down of Dvl. Moreover, our data suggest that Dvl may relieve the anti-apoptotic effect of NF-KB, thus play a role in promoting apoptosis. Therefore, this work demonstrates a novel function of Dvl in modulating NF-KB-regulated gene transcription. 展开更多
关键词 Dishevelled (Dvl) NF-kB p65 transcriptional suppressor Wnt signaling
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Resistin levels of serum and follicular fluid in non-obese patients with polycystic ovary syndrome during IVF cycles 被引量:1
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作者 陆秀娥 黄荷凤 +3 位作者 郦美根 朱依敏 钱羽力 董旻岳 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2005年第9期897-902,共6页
Objectives: To measure serum and follicular resistin, steroids hormone levels in women with PCOS (polycystic ovary syndrome) (BMI (body mass index)<25 kg/m2), to assess possible correlations of resistin to hormonal... Objectives: To measure serum and follicular resistin, steroids hormone levels in women with PCOS (polycystic ovary syndrome) (BMI (body mass index)<25 kg/m2), to assess possible correlations of resistin to hormonal and metabolic parameters and to analyze the clinical outcomes of in vitro fertilization-embryo transfer (IVF-ET) in women with PCOS and tubal infertility. Study design: We analyzed the clinical outcomes of IVF-ET in women with PCOS (BMI<25 kg/m2) and tubal infertility during the years 2002 to 2004 and compared the serum and follicular fluid resistin levels, estradiol (E2), progesterone (P), testosterone (T) levels in 20 PCOS and 20 healthy, age-matched women without PCOS during IVF-stimulated cycles. The correlations between the resistin levels and the outcomes of IVF-ET were evaluated. Results: No significant differences in resistin levels of either serum or follicular fluid between PCOS and control group were found. However, resistin levels in serum were higher than that in follicular fluid in both groups. Multiple regression analysis showed that resistin levels in serum did not correlate with BMI, estradiol, LH (luteinizing hormone) and insulin level in fasting blood. No significant correlations were found between follicular fluid reisistin levels and fertilization rate, implantation rate, clinical pregnancy rate or early miscarriage rate in both PCOS and control groups. Conclusion: Our results show that resistin does not have correlation with the hormonal and metabolic parameters as well as the outcomes of IVF. These data suggest that resistin is unlikely to be a local determinant factor in steroidogenesis and growth and maturation of oocytes during IVF-ET in lean women with PCOS. 展开更多
关键词 Insulin resistance RESISTIN In vitro fertilization-embryo transfer Polycystic ovary syndrome
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Autoantibody profiles in autoimmune hepatitis and chronic hepatitis C identifies similarities in patients with severe disease 被引量:6
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作者 Kawa Amin Aram H Rasool +3 位作者 Ali Hattem Taha AM Al-Karboly Taher E Taher Jonas Bystrom 《World Journal of Gastroenterology》 SCIE CAS 2017年第8期1345-1352,共8页
To determine how the auto-antibodies (Abs) profiles overlap in chronic hepatitis C infection (CHC) and autoimmune hepatitis (AIH) and correlate to liver disease.METHODSLevels of antinuclear Ab, smooth muscle antibody ... To determine how the auto-antibodies (Abs) profiles overlap in chronic hepatitis C infection (CHC) and autoimmune hepatitis (AIH) and correlate to liver disease.METHODSLevels of antinuclear Ab, smooth muscle antibody (SMA) and liver/kidney microsomal-1 (LKM-1) Ab and markers of liver damage were determined in the sera of 50 patients with CHC infection, 20 AIH patients and 20 healthy controls using enzyme linked immunosorbent assay and other immune assays.RESULTSWe found that AIH patients had more severe liver disease as determined by elevation of total IgG, alkaline phosphatase, total serum bilirubin and serum transaminases and significantly higher prevalence of the three non-organ-specific autoantibodies (auto-Abs) than CHC patients. Antinuclear Ab, SMA and LKM-1 Ab were also present in 36% of CHC patients and related to disease severity. CHC cases positive for auto-Abs were directly comparable to AIH in respect of most markers of liver damage and total IgG. These cases had longer disease duration compared with auto-Ab negative cases, but there was no difference in gender, age or viral load. KLM-1<sup>+</sup> Ab CHC cases showed best overlap with AIH.CONCLUSIONAuto-Ab levels in CHC may be important markers of disease severity and positive cases have a disease similar to AIH. Auto-Abs might have a pathogenic role as indicated by elevated markers of liver damage. Future studies will unravel any novel associations between these two diseases, whether genetic or other. 展开更多
关键词 AUTOANTIBODY Inflammatory diseases Immune system Hepatitis C virus Smooth muscle antibody Liver/kidney microsomal-1 autoantibody Anti-nuclear antibody
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Simulation of rock deformation and mechanical characteristics using clump parallel-bond models 被引量:10
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作者 夏明 赵崇斌 《Journal of Central South University》 SCIE EI CAS 2014年第7期2885-2893,共9页
To properly simulate hard rock with a high ratio of the uniaxial compressive strength to tensile strength(UCS/TS) and realistic strength-failure envelope,the rock deformation and mechanical characteristics were discus... To properly simulate hard rock with a high ratio of the uniaxial compressive strength to tensile strength(UCS/TS) and realistic strength-failure envelope,the rock deformation and mechanical characteristics were discussed in detail when the particle simulation method with the clump parallel-bond model(CPBM) was used to conduct a series of numerical experiments at the specimen scale.Meanwhile,the effects of the loading procedure and crack density on the mechanical behavior of a specimen,which was modeled by the particle simulation method with the CPBM,were investigated.The related numerical results have demonstrated that:1) The uniaxial compressive strength(UCS),tensile strength(TS) and elastic modulus are overestimated when the conventional loading procedure is used in the particle simulation method with the CPBM; 2) The elastic modulus,strength and UCS/TS decrease,while Poisson ratio increases with the increase of the crack density in the particle simulation method with the CPBM; 3) The particle simulation method with the CPBM can be used to reproduce a high value of UCS/TS(>10),as well as a high friction angle and reasonable cohesion strength; 4) As the confining pressure increases,both the peak strength of the simulated specimen and the number of microscopic cracks increase,but the ratio of tensile cracks number to shear cracks number decreases in the particle simulation method with the CPBM; 5) Compared with the conventional parallel-bond model,the CPBM can be used to reproduce more accurate results for simulating the rock deformation and mechanical characteristics. 展开更多
关键词 particle simulation method clump parallel-bond model crack density loading procedure rock mechanical behavior
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Compact dual-band bandpass filter for WLAN systems 被引量:1
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作者 朱晨 周健义 《Journal of Southeast University(English Edition)》 EI CAS 2010年第4期509-512,共4页
A novel dual-band planar microstrip filter using parallel coupled microstrip lines and open-loop stepped-impedance resonators(SIRs)loaded with two shunt open stubs is presented.By tuning the physical lengths of open... A novel dual-band planar microstrip filter using parallel coupled microstrip lines and open-loop stepped-impedance resonators(SIRs)loaded with two shunt open stubs is presented.By tuning the physical lengths of open-loop SIRs,parallel coupled microstrip lines and two stubs,the bandpass filter has good dual-passband performance at 2.55 and 5.35 GHz and high isolation between the two passbands.The relative bandwidths of the two passbands are 11.8% and 16.8%,respectively.Compared with the conventional open-loop SIR filters,the designed filter has a comparatively broader fractional bandwidth at the second passband.So it can cover all the wireless LAN(local area network)bands.In addition,the filter has the features of low loss,high rejection and low ripple.The measured results are in good agreement with the simulated responses by HFSS software. 展开更多
关键词 DUAL-BAND parallel coupled microstrip lines stepped-impedance-resonators(SIRs)
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A new method to calculate lateral force acting on stabilizing piles based on multi-wedge translation mechanism 被引量:2
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作者 罗渝 许强 +3 位作者 何思明 李新坡 何尽川 吴永 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第2期654-661,共8页
A new method based on the multi-wedge translation mechanism is presented to calculate the lateral force acting on the stabilizing piles. At first, there is no assumption for the shape of potential sliding surface, it ... A new method based on the multi-wedge translation mechanism is presented to calculate the lateral force acting on the stabilizing piles. At first, there is no assumption for the shape of potential sliding surface, it is just considered that the potential sliding surface is a composite of a number of straight lines. And then, the potential sliding mass is divided into a number of triangular wedges take with these straight lines as its base. The kinematic theorem of limit analysis is adopted to calculate the rate of external work and the rate of energy dissipation for each triangular wedge, respectively. Furthermore, the multivariate functions are established to calculate the lateral force acting on the stabilizing piles. The lateral force and the corresponding potential sliding surfaces can be obtained by an optimizational technique. At last, an example is taken to illustrate the method. The effect of soil strength parameters, slope angle and pile roughness on the lateral force and the corresponding potential sliding surface are analyzed.The result are compared with those obtained using other methods. 展开更多
关键词 PILE sliding surface limit analysis multi-wedge mechanism
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Comparison of Antioxidant Activity and Antioxidant Components in Lettuce, Onion and Tomato Obtained with Different Levels and Forms of Nitrogen Fertilization
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作者 Ragab Abdelmohsen E1-Mergawi Khalid Naser Al-Redhaiman Hussein F. Abouziena 《Journal of Agricultural Science and Technology(A)》 2014年第7期597-604,共8页
The effect of N levels and sources on the antioxidant components in vegetable is not completely understood. Therefore, greenhouse experiments were conducted to determine the changes in antioxidant capacity diphenyl-2-... The effect of N levels and sources on the antioxidant components in vegetable is not completely understood. Therefore, greenhouse experiments were conducted to determine the changes in antioxidant capacity diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP), total phenolics, ascorbic acid, total carotene and lycopene contents in edible portions of lettuce, onion and tomato due to different nitrogen levels and sources. The experiment included three N levels (20, 40 and 60 kg/ha for lettuce trial and 60, 120 and 180 kg/ha for either onion or tomato) and four nitrogen sources (calcium nitrate, ammonium sulphate, ammonium nitrate and urea). The antioxidant capacity and phenolic contents in lettuce was enhanced under low nitrogen level, while the antioxidant capacities, phenolics, carotenoids and lycopene in tomato fruits were not significantly affected by the nitrogen dose applied. Application of calcium nitrate caused 50% increase in DPPH and 20% in FRAP of lettuce compared to other nitrogen forms. Tomato treated with calcium nitrate or ammonium sulphate had higher phenolic and ascorbic acid contents than treated plants with ammonium nitrate or urea. Antioxidant tested parameters of onion were not significantly affected by the nitrogen treatments. Nitrogen concentration in tomato fruits significantly correlated with FRAP antioxidant capacity, phenolics, ascorbic acid, carotene and lycopene contents. 展开更多
关键词 Ammonium nitrate ammonium sulphate ascorbic acid calcium nitrate CAROTENE phenolics urea.
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Clinical implications of fatty pancreas:Correlations between fatty pancreas and metabolic syndrome 被引量:47
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作者 Jun Seok Lee Sang Heum Kim +8 位作者 Dae Won Jun Jee Hye Han Eun Chul Jang Ji Young Park Byung Kwan Son Seong Hwan Kim Yoon Ju Jo Young Sook Park Yong Soo Kim 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第15期1869-1875,共7页
AIM:To investigate the clinical implications of lipid deposition in the pancreas(fatty pancreas). METHODS:The subjects of this study were 293 patients who had undergone abdominal computed tomography(CT)and sonography.... AIM:To investigate the clinical implications of lipid deposition in the pancreas(fatty pancreas). METHODS:The subjects of this study were 293 patients who had undergone abdominal computed tomography(CT)and sonography.Fatty pancreas was diagnosed by sonographic findings and subdivided into mild,moderate,and severe fatty pancreas groups comparing to the retroperitoneal fat echogenicity. RESULTS:Fatty pancreas was associated with higher levels for visceral fat,waist circumference,aspartate aminotransferase(AST),alanine aminotransferase (ALT),total cholesterol,triglyceride,high density lipoprotein,free fatty acid,γ-GTP,insulin,and the homeostasis model assessment of insulin resistance (HOMA-IR)than the control group(P<0.05).HOMAIR,visceral fat,triglyceride,and ALT also tended to increase with the degree of fat deposition in the pancreas on sonography.In a multivariate logistic regression analysis,HOMA-IR,visceral fat,and ALT level were independently related to fatty pancreas after adjustment for age,body mass index,and lipid profile.The incidence of metabolic syndrome in the fatty pancreas group was significantly higher than in the control group,and the numbers of metabolic syndrome parameters were significantly higher in the fatty pancreas group(P<0.05).CONCLUSION:Sonographic fatty pancrease showed higher insulin resistance,visceral fat area,triglyceride, and ALT levels than normal pancreases.Fatty pancreas also showed a strong correlation with metabolic syndrome. 展开更多
关键词 Fatty pancreas Metabolic syndrome Insulin resistance
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Establishment and Preliminary Application of a Rapid Fluorescent Focus Inhibition Test (RFFIT) for Rabies Virus 被引量:11
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作者 Pengcheng Yu Xinjun Lv +2 位作者 Xinxin Shen Qing Tang Guodong Liang 《Virologica Sinica》 SCIE CAS CSCD 2013年第4期223-227,共5页
The World Health Organization (WHO) standard assay for determining levels of the rabies virus neutralization antibody (RVNA) is the rapid fluorescent focus inhibition test (RFFIT), which is used to evaluate the immuni... The World Health Organization (WHO) standard assay for determining levels of the rabies virus neutralization antibody (RVNA) is the rapid fluorescent focus inhibition test (RFFIT), which is used to evaluate the immunity effect after vaccination against rabies. For RFFIT, CVS-11 was used as the challenge virus, BSR cells as the adapted cells, and WHO rabies immunoglobulin (WHO STD) as the reference serum in this study. With reference to WHO and Pasteur RFFIT procedures, a micro-RFFIT procedure adapted to our laboratory was produced, and its specificity and reproducibility were tested. We tested levels of RVNA in human serum samples after immunization with different human rabies vaccines (domestic purified Vero cell rabies vaccine (PVRV) and imported purified chick embryo cell vaccine (PCECV)) using different regimens (Zagreb regimen and Essen regimen). We analyzed the levels of RVNA, and compared the immune efficacy of domestic PVRV and imported PCECV using different immunization regimens. The results showed that the immune efficacy of domestic PVRV using the Zagreb regimen was as good as that of the imported PCECV, but virus antibodies were generated more rapidly with the Zagreb regimen than with the Essen regimen. The RFFIT procedure established in our laboratory will enhance the comprehensive detection ability of institutions involved in rabies surveillance in China. 展开更多
关键词 Rapid fluorescent focus inhibition test (RFFIT) RVNA RABIES Vaccination regimen
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