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D18, an eximious solar polymer! 被引量:25
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作者 Ke Jin Zuo Xiao Liming Ding 《Journal of Semiconductors》 EI CAS CSCD 2021年第1期24-28,29-30,共7页
Organic solar cell(OSC)is a promising photovoltaic technology with great commercialization potential due to the advantages like solution-processing,roll-to-roll fabrication,lightweight,flexibility,and semitransparency... Organic solar cell(OSC)is a promising photovoltaic technology with great commercialization potential due to the advantages like solution-processing,roll-to-roll fabrication,lightweight,flexibility,and semitransparency[1−7].Conjugated polymer donors are key materials for OSCs[8]. 展开更多
关键词 POLYMER TRANSPARENCY semi
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半潜式生产平台发展现状及应用浅析 被引量:21
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作者 杜庆贵 冯玮 +2 位作者 时忠民 姜哲 刘小燕 《石油矿场机械》 2015年第10期72-78,共7页
研究了新建半潜式生产平台的发展历程,分析了其设计变迁及建造、总装方案,列举了曾经发生过的2起重大事故,总结了半潜式生产平台的发展趋势,最后对其在中国南海的应用和发展提出了一些想法。
关键词 半潜式生产平台 总装 事故
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铝合金表面激光熔覆Fe-Al青铜过渡区的组织结构及其在小能多冲作用下的行为 被引量:10
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作者 王爱华 谢长生 +1 位作者 李树栋 聂继红 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 1999年第5期289-292,共4页
研究了Al-Si合金表面激光熔覆Fe-Al青铜合金过渡区的组织和相结构;探讨了在小能量多冲作用下过渡区的行为。结果表明:熔覆层/基材间过渡区的组织和相结构存在一定的层次,靠近熔覆层的一侧为不均匀的块状Cu9Al4+Cu3Al;中间区为块... 研究了Al-Si合金表面激光熔覆Fe-Al青铜合金过渡区的组织和相结构;探讨了在小能量多冲作用下过渡区的行为。结果表明:熔覆层/基材间过渡区的组织和相结构存在一定的层次,靠近熔覆层的一侧为不均匀的块状Cu9Al4+Cu3Al;中间区为块状Cu9Al4+针状CuAl2;向基材靠近时,过渡区的针状CuAl2相逐渐减少,α-Al相逐渐增多。在小能多冲作用下,过渡区裂纹形成干脆性相CUAl2富集的区域,激光扫描速度对CUAl2相在过渡区的分布厚度影响显著,进而影响到过渡区的抗小能多冲行为。扫描速度在10mm/s~12mm/s时,熔覆层具有较高的抗冲击性能;扫描速度≤8mm/s或≥14mm/s时,其抗冲击性能显著降低。 展开更多
关键词 铝合金 激光熔覆 过渡区 组织结构 小能多冲
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Dynamical coarsening processes of microstructures in non dendritic AlSi_7Mg alloy remelted in semi solid state 被引量:9
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作者 毛卫民 崔成林 +2 位作者 赵爱民 孙峰 钟雪友 《中国有色金属学会会刊:英文版》 CSCD 2000年第1期25-28,共4页
The microstructural variation in the non dendritic AlSi 7Mg samples remelted in the semi solid state has been investigated. It is proposed that the primary α Al phases are mainly coarsened by connecting the secondary... The microstructural variation in the non dendritic AlSi 7Mg samples remelted in the semi solid state has been investigated. It is proposed that the primary α Al phases are mainly coarsened by connecting the secondary arms or fine primary α Al phases together at the stage of a small quantity of liquid and slowly coarsened through diffusion at the stage of a great quantity of liquid. The dynamical coarsening equation controlled by diffusion is in good agreement with the equation of d 3- d 3 0= kt and the effect of the starting microstructures on the coarsening of primary α Al phases is gradually decreased when the soaking time is long enough. 展开更多
关键词 aluminium alloy semi solid ISOTHERMAL REMELTING microstructure
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Preparation of 2024/3003 gradient materials by semi-continuous casting using double-stream-pouring technique 被引量:14
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作者 李元元 费劲 +2 位作者 陈维平 张卫文 邵明 《Journal of Central South University of Technology》 2002年第4期229-234,共6页
The 2024/3003 aluminum gradient alloys are prepared by semi continuous casting. The influences of throttle bore diameter of embedded nozzle and temperature of internal melt on composition distribution, macrostructure,... The 2024/3003 aluminum gradient alloys are prepared by semi continuous casting. The influences of throttle bore diameter of embedded nozzle and temperature of internal melt on composition distribution, macrostructure, hardness are analyzed, and the stability of gradient distribution of composition, macrostructure and hardness along the axial direction of the ingot is also studied. The results show that diffe rent composition profiles can be achieved by adjusting the processing parameters; the volume fraction of inner alloy in the ingot can be increased by enlarging the throttle bore diameter and elevating the temperature of inner melt; quasi steady solidification can be realized within 20 s during cast processing, and consistent quality ingot is obtained by controlling the casting speed and liquid height of inner melt. 展开更多
关键词 Al alloys gradient materials semi continuous casting
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A Characterization of Continuous Module Homomorphisms on Random Semi—Normed Modules and Its Applications 被引量:12
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作者 TieXinGUO 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2003年第1期201-208,共8页
In this paper, a characterization of continuous module homomorphisms on random semi-normed modules is first given; then the characterization is further used to show that the Hahn-Banach type of extension theorem is st... In this paper, a characterization of continuous module homomorphisms on random semi-normed modules is first given; then the characterization is further used to show that the Hahn-Banach type of extension theorem is still true for continuous module homomorphisms on random semi-normed modules. 展开更多
关键词 Random semi normed modules Continuous module homomorphisms Extension theorems
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Effects of fencing on vegetation and soil restoration in a degraded alkaline grassland in northeast China 被引量:12
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作者 Qiang LI DaoWei ZHOU +3 位作者 YingHua JIN MinLing WANG YanTao SONG GuangDi LI 《Journal of Arid Land》 SCIE CSCD 2014年第4期478-487,共10页
In order to restore a degraded alkaline grassland, the local government implemented a large restoration project using fences in Changling county, Jilin province, China, in 2000. Grazing was excluded from the protected... In order to restore a degraded alkaline grassland, the local government implemented a large restoration project using fences in Changling county, Jilin province, China, in 2000. Grazing was excluded from the protected area, whereas the grazed area was continuously grazed at 8.5 dry sheep equivalent(DSE)/hm2. In the current research, soil and plant samples were taken from grazed and fenced areas to examine changes in vegetation and soil properties in 2005, 2006 and 2008. Results showed that vegetation characteristics and soil properties improved significantly in the fenced area compared with the grazed area. In the protected area the vegetation cover, height and above- and belowground biomass increased significantly. Soil pH, electrical conductivity and bulk density decreased significantly, but soil organic carbon and total nitrogen concentration increased greatly in the protected area. By comparing the vegetation and soil characteristics with pre-degraded grassland, we found that vegetation can recover 6 years after fencing, and soil pH can be restored 8 years after fencing. However, the restoration of soil organic carbon, total nitrogen and total phosphorus concentrations needed 16, 30 and 19 years, respectively. It is recommended that the stocking rate should be reduced to 1/3 of the current carrying capacity, or that a grazing regime of 1-year of grazing followed by a 2-year rest is adopted to sustain the current status of vegetation and soil resources. However, if N fertilizer is applied, the rest period could be shortened, depending on the rate of application. 展开更多
关键词 vegetation and soil restoration FENCING GRAZING alkaline soil semi arid region grassland degradation
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Solving type-2 fuzzy relation equations via semi-tensor product of matrices 被引量:10
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作者 Yongyi YAN Zengqiang CHEN Zhongxin LIU 《Control Theory and Technology》 EI CSCD 2014年第2期173-186,共14页
The problem of solving type-2 fuzzy relation equations is investigated. In order to apply semi-tensor product of matrices, a new matrix analysis method and tool, to solve type-2 fuzzy relation equations, a type-2 fuzz... The problem of solving type-2 fuzzy relation equations is investigated. In order to apply semi-tensor product of matrices, a new matrix analysis method and tool, to solve type-2 fuzzy relation equations, a type-2 fuzzy relation is decomposed into two parts as principal sub-matrices and secondary sub-matrices; an r-ary symmetrical-valued type-2 fuzzy relation model and its corresponding symmetrical-valued type-2 fuzzy relation equation model are established. Then, two algorithms are developed for solving type-2 fuzzy relation equations, one of which gives a theoretical description for general type-2 fuzzy relation equations; the other one can find all the solutions to the symmetrical-valued ones. The results can improve designing type-2 fuzzy controllers, because it provides knowledge to search the optimal solutions or to find the reason if there is no solution. Finally some numerical examples verify the correctness of the results/algorithms. 展开更多
关键词 Fuzzy control system Type-2 fuzzy logic system Type-2 fuzzy relation Type-2 fuzzy relation equation semi- tensor product of matrices
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The effect of vitamin D on sperm motility and the underlying mechanism 被引量:11
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作者 Kadiliya Jueraitetibaike Zheng Ding +6 位作者 Dan-Dan Wang Long-Ping Peng Jun Jing Li Chen Xie Ge Xu-Hua Qiu Bing Yao 《Asian Journal of Andrology》 SCIE CAS CSCD 2019年第4期400-407,共8页
Vitamin D deficiency is a common health issue around the world. We therefore evaluated the associations of semen quality with both serum and seminal plasma vitamin D levels and studied the mechanisms underlying these ... Vitamin D deficiency is a common health issue around the world. We therefore evaluated the associations of semen quality with both serum and seminal plasma vitamin D levels and studied the mechanisms underlying these by incubating spermatozoa with 1,25(OH)2D in vitro. Two hun dred and twenty-two men were in eluded in our study. Vitamin D was detected using an electrochemilumi nesce nee method. Spermatozoa used for in vitro experiments were isolated by density gradient centrifugation. Positive relationships of serum 25(OH)D with semen volume and seminal plasma fructose were identified. Seminal plasma 25(OH)D level showed no relationship with serum 25(OH)D level, while it was inversely associated with sperm concentration and positively correlated with semen volume and sperm kinetic values. In vitro, sperm kinetic parameters in creased after in cubation with 1,25(OH)2D, especially upon in cubation for 30 min with it at a concen tration of 0.1 nmol l-1. Under these in cubation conditions, the upward migratio n of spermatozoa in creased remarkably with increasing ade nosine triphosphate (ATP) con centratio n. The concentrati on of cyclic ade nosine mono phosphate (cAMP) and the activity of protei n kinase A (PKA) were both elevated, and the PKA inhibitor, N-[2-(p-Bromocinnamylamino)ethyl]-5-isoquinolinesulfonamide dihydrochloride (H89) reversed the in crease of ATP producti on. The conce ntrations of cytoplasmic calcium ions and n icotinamide adenine dinucleotide (NADH) were both enhanced, while mitochondrial calcium uniporter (MCU) inhibitor, Ruthenium 360 (Ru360) did not reverse the increase of ATP production. Therefore, seminal plasma vitamin D may be invoIved in regulating sperm motility, and 1,25(OH)2D may enhance sperm motility by promoting the synthesis of ATP both through the cAMP/PKA pathway and the in crease in in tracellular calcium ions. 展开更多
关键词 ade no SINE TRIPHOSPHATE semi nal plasma SPERM MOTILITY VITAMIN D
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SEMI标准在半导体制造设备中的应用 被引量:2
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作者 韦薇 林煦呐 +2 位作者 张帅 谢琼 杨师 《电子工业专用设备》 2023年第2期58-63,共6页
SEMI标准是一项国际通用的半导体行业标准,为研究SEMI标准在半导体制造设备中的应用情况,介绍了SEMI S2半导体设备安全准则、SEMI F47半导体设备电压暂降抗扰度标准并说明了标准的实际应用。分析了SEMI S23半导体设备能源、电力和原料... SEMI标准是一项国际通用的半导体行业标准,为研究SEMI标准在半导体制造设备中的应用情况,介绍了SEMI S2半导体设备安全准则、SEMI F47半导体设备电压暂降抗扰度标准并说明了标准的实际应用。分析了SEMI S23半导体设备能源、电力和原料的使用效率标准、SECS/GEM通讯标准及其研究应用现状;提出了我国半导体产业的快速发展需要加大SEMI标准的普及应用。 展开更多
关键词 半导体制造设备 semi S2标准 semi F47标准
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Cosmic Dark Energy Density from Classical Mechanics and Seemingly Redundant Riemannian Finitely Many Tensor Components of Einstein’s General Relativity 被引量:8
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作者 Mohamed El Naschie 《World Journal of Mechanics》 2014年第6期153-156,共4页
We determine the limit of the ratio formed by the independent components of the Riemann tensor to the non-zero component as space dimensionality tends to infinity and find it to be 12. Subsequently we use this result ... We determine the limit of the ratio formed by the independent components of the Riemann tensor to the non-zero component as space dimensionality tends to infinity and find it to be 12. Subsequently we use this result in conjunction with Newtonian classical mechanics to show that the ordinary measurable cosmic energy density is given by while the dark energy density is obviously the Legendre transformation dual energy E(D) = 1 -?E(O). The result is in complete agreement with the COBE, WMAP and type 1a supernova measurements. 展开更多
关键词 semi Classical Quantum Systems Dark Energy Accelerated COSMIC Expansion RIEMANNIAN TENSOR Infinite Dimensional Topology NONLOCAL Elasticity
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Effect of Mg and semi solid processing on microstructure and impression creep properties of A356 alloy 被引量:9
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作者 B.AMIR ESGANDARI B.NAMI +1 位作者 M.SHAHMIRI A.ABEDI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第9期2518-2523,共6页
The effects of Mg and semi solid processing on the creep properties ofA356 A1 alloy were investigated. The results show that the dislocation climb controlled creep is the dominant creep mechanism and it is not affecte... The effects of Mg and semi solid processing on the creep properties ofA356 A1 alloy were investigated. The results show that the dislocation climb controlled creep is the dominant creep mechanism and it is not affected by the semi solid processing and further addition of Mg. Mg improves the alloy creep properties probably by forming large Chinese script Mg2Si compounds at the interdendritic regions. The semi solid processed specimens exhibit better creep properties in comparison with the as cast ones. It is attributed to the reduction in the stacking fault energy resulting from the significant dissolution of Mg in the a(A1) phase. 展开更多
关键词 A356 alloy MICROSTRUCTURE semi solid processing impression creep dislocation climb controlled creep
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初治肺结核病人T淋巴细胞亚群的表达及与化学药物治疗的相关性 被引量:8
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作者 万引 徐漫清 张爱妹 《江西医药》 CAS 2015年第12期1323-1325,共3页
目的探讨初治肺结核病人外周血中CD_3^+、CD_4^+、CD_8^+T淋巴细胞表达水平及与化学药物治疗的相关性。方法采用Semi Bio特异性细胞检测方法,分别检测正常健康人、初治肺结核病人、初治肺结核病人经正规抗痨方案强化治疗2个月后外周血中... 目的探讨初治肺结核病人外周血中CD_3^+、CD_4^+、CD_8^+T淋巴细胞表达水平及与化学药物治疗的相关性。方法采用Semi Bio特异性细胞检测方法,分别检测正常健康人、初治肺结核病人、初治肺结核病人经正规抗痨方案强化治疗2个月后外周血中CD_3^+、CD_4^+、CD_8^+T淋巴细胞表达水平。结果与健康对照组相比,肺结核患者外周血CD_3^+、CD_4^+、CD_8^+T升高,CD_4^+/CD_8^+比值下降(P<0.05);经过两个月化学药物正规抗结核治疗后CD_3^+、CD_4^+、CD_4^+/CD_8^+有升高(P<0.05)。结论肺结核病人细胞免疫功能低下,经化学药物抗结核治疗后免疫功能有升高。 展开更多
关键词 肺结核 T淋巴细胞亚群 semi Bio细胞检测 化学药物治疗
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用于芯片工厂的模块化高频UPS的配电拓扑分析
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作者 周路来 《内燃机与配件》 2024年第14期103-105,共3页
本文论述了用于极高可靠性供电要求的场合如芯片工厂的配电架构改良,单独内燃机驱动的柴油发电机组(下文简称柴发)作为后备电源进行供电保障优化为结合储能以及不间断电源(Uninterrupted Power Supply,下文简称UPS)相组合的供电保障,UP... 本文论述了用于极高可靠性供电要求的场合如芯片工厂的配电架构改良,单独内燃机驱动的柴油发电机组(下文简称柴发)作为后备电源进行供电保障优化为结合储能以及不间断电源(Uninterrupted Power Supply,下文简称UPS)相组合的供电保障,UPS的接线拓扑分析以及采用预充磁装置对优化的拓扑进行进一步改良。 展开更多
关键词 芯片工厂 semi F47-0200-2000 内燃机驱动的柴油发电机组 后备电源 UPS(不间断电源) 拓扑 涌流 预充磁
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Comparison of Concrete Carbonation Process under Natural Condition and High CO_2 Concentration Environments 被引量:6
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作者 姬永生 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第3期515-522,共8页
To compare the results obtained under both natural and accelerated environments,the pH values of carbonated concrete were measured,the variation of pH values was determined,and the variations of Ca(OH)2 and CaCO3 co... To compare the results obtained under both natural and accelerated environments,the pH values of carbonated concrete were measured,the variation of pH values was determined,and the variations of Ca(OH)2 and CaCO3 contents in the carbonated concrete under natural condition and high CO2 concentration accelerated climate environments were determined by microcosmic test methods such as DTA and X-ray diffraction.The experimental results showed that the overall variation trend of pH values and phase component of carbonation layer of concrete under accelerated climate environments with high CO2 concentrations were the same as those under natural conditions.Therefore,the carbonation processes of concrete were considered consistent under both conditions.However there was a difference in the length of semi-carbonation zones.The one measured under high CO2 concentration accelerated climate environments was shorter than that under natural condition.Experimental investigation showed that it was caused by the differences in climate condition(temperature and relative humidity) as well as the properties of the concrete.The concentration of CO2 and the duration of the carbonation process have no effect on the length of semi-carbonation zone.Thus,it is acceptable to simulate the natural condition by applying the high CO2 concentration artificial accelerated carbonation technique for the purpose of the study of carbonation process of concrete. 展开更多
关键词 natural carbonation artificial accelerated carbonation phase component semi carbonation zone CORRELATION
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避免电压瞬降对设备影响的技术研究
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作者 姜慧慧 高智刚 《山西电子技术》 2024年第2期120-122,共3页
主要阐述了什么是SEMI F47电压瞬降,SEMI F47的标准曲线及测试特性规范,如何预防电压瞬降的技术措施,通过一系列措施的改进、参数设置、线路改进等使设备具有应对电压瞬降的能力,保证设备正常运行。
关键词 semi F47 电压瞬降 预防措施
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电压暂降对工业厂房内敏感负荷影响研究
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作者 张宁 艾鑫 王泽峰 《智能建筑电气技术》 2024年第3期80-84,共5页
针对电压暂降对工业厂房敏感负荷正常生产可能造成的影响进行研究,首先对电压暂降的概念和相关标准进行阐述,之后通过分析电压暂降形成的原因、工厂中常用设备的敏感特性曲线分析、现场测量的数据等,并结合某工厂实际在运行过程中存在... 针对电压暂降对工业厂房敏感负荷正常生产可能造成的影响进行研究,首先对电压暂降的概念和相关标准进行阐述,之后通过分析电压暂降形成的原因、工厂中常用设备的敏感特性曲线分析、现场测量的数据等,并结合某工厂实际在运行过程中存在的问题研究,提出针对不同情况电压暂降原因的解决方案,最后通过工厂实际实施项目及现场测量数据,较为完整地说明工厂电压暂降的治理措施。 展开更多
关键词 电压暂降 电压暂降与短时中断 电能质量在线检测 电压耐受曲线 semi F47曲线 ITIC曲线 电能质量 敏感性负荷
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Implementation of an in-house flow cytometric analysis of DNA fragmentation in spermatozoa 被引量:7
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作者 Anne Sofie Rex Chunsen Wu +1 位作者 Jorn Aagaard Jens Fedder 《Asian Journal of Andrology》 SCIE CAS CSCD 2020年第3期246-251,共6页
An increased amount of DNA fragme ntation in the spermatozoa(SDF)is linked to male in fertility.The Sperm Chromati n Structure Assay(SCSA)is widely used for analysis of SDF.However,the current software(SCSASoftR)linke... An increased amount of DNA fragme ntation in the spermatozoa(SDF)is linked to male in fertility.The Sperm Chromati n Structure Assay(SCSA)is widely used for analysis of SDF.However,the current software(SCSASoftR)linked to this assay is licensed and often located within larger diagnostic centers.In this study,we present a protocol for using other types of software than SCSASoftR to determine the SDF index(DFI)with clinical relevance.This protocol is engineered after collect!ng and analyzing 254 samples from fertility patients and sperm donors over a 15-month period.DFI is analyzed using a strict protocol where the spermatozoa are treated with a strong acid(pH 1.2)followed by acridine orange.DFI is determined by a standard flow cytometric software,FACSDiva 6.1.3.Analysis of the outcome of the fertility treatment is included for 137 patients receiving either intrauterine inseminations(IUI)or timed coitus(TC).The results show that the chance of pregnancy decli nes as DFI in creases.We also found that the male DFI affects the chanee of pregnancy independent of the female age.We have shown that a standard flow cytometric software can be used when determi ning a clinical releva nt DFI.These findings are a sign ificant step toward impleme nting the an alysis as a part of the routi ne,in・house diag no sing of the male fertility patient and subseque ntly optimizing the treatme nt course of the couple with reduced human and financial costs. 展开更多
关键词 DNA fragme ntation flow cytometry in-house an alysis in trauteri ne in semi natio n Sperm Chromati n Structure Assay SPERMATOZOA
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Experimental Study on Magnetorheological Damper for Semi-Active Vibration Control of Civil Infrastructures 被引量:4
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作者 李忠献 徐龙河 《Transactions of Tianjin University》 EI CAS 2004年第1期19-23,共5页
Magnetorheological (MR) fluid is a kind of smart material whose rheological properties can be rapidly varied in magnetic field. To make full use of the advantages of MR fluid to devices, a model of double ended, shear... Magnetorheological (MR) fluid is a kind of smart material whose rheological properties can be rapidly varied in magnetic field. To make full use of the advantages of MR fluid to devices, a model of double ended, shear combined and valve typed MR damper is designed and manufactured, and the dynamic properties under sinusoidal excitations are experimentally studied. The experiment results show that the maximum damping force of the MR damper at the full magnetic intensity reaches about 20 kN while the maximum power required is less than 50 W, which predicts that the MR damper will be a powerful measurement for semi active vibration control of civil infrastructures. 展开更多
关键词 civil infrastructure semi active vibration control magnetorheological (MR) damper dynamic behavior magnetic intensity
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推广的半绝对离差和动态投资组合选择 被引量:3
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作者 郭福华 邓飞其 《应用数学》 CSCD 北大核心 2007年第3期446-451,共6页
在标准的Black-Scholes型金融市场下,建立了以推广的半绝对离差(Extended Semi-Absolute Deviation;ESAD)度量风险的动态均值-ESAD投资组合选择模型,研究了模型的求解方法,得到了最优投资组合策略和均值-ESAD有效前沿的解析表达式.同时... 在标准的Black-Scholes型金融市场下,建立了以推广的半绝对离差(Extended Semi-Absolute Deviation;ESAD)度量风险的动态均值-ESAD投资组合选择模型,研究了模型的求解方法,得到了最优投资组合策略和均值-ESAD有效前沿的解析表达式.同时,与动态均值-方差模型作了比较分析.最后,结合实例说明了模型的求解方法. 展开更多
关键词 semi A.D ESAD 动态投资组合 有效前沿
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