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Hepatitis B Immunoprophylactic Failure and Characteristics of the Hepatitis B Virus Gene in Mother-Infant Pairs in Parts of China 被引量:3
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作者 YIN Wen Jiao SHEN Li Ping +8 位作者 WANG Fu Zhen ZHANG Guo Min ZHENG Hui WANG Feng LIU Tie Zhu MENG Qing Ling YI Yao CUI Fu Qiang BI Sheng Li 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2016年第11期790-801,共12页
Objective To determine the hepatitis B immunoprophylactic failure rate in infants born to hepatitis B virus (HBV) infected mothers and to characterize HBV genes. Methods HBV-serological testing was conducted for pre... Objective To determine the hepatitis B immunoprophylactic failure rate in infants born to hepatitis B virus (HBV) infected mothers and to characterize HBV genes. Methods HBV-serological testing was conducted for pregnant women and infants. The complete genomes of 30 HBV isolates were sequenced, and genetic characteristics were analyzed using MEGA 5 software. Results The immunoprophylactic failure rate for infants who had completed the scheduled hepatitis B vaccination program was 5.76% (32/556). High sequence homology (99.8%-100%) was observed in 8 of the 10 mother-infant pairs. We identified 19 subgenotype C2 strains, 9 subgenotype B2 strains, and 2 subgenotype Cl strains. Three serotypes were detected: adr (19/30), adw (9/30), and ayw (2/30). The frequency of amino acid mutation of the 'a' determinant region was 16.67% (5/30), including that of Q129H, F134Y,S136Y, and G145E. We detected 67 amino acid mutations in the basal core promoter, precore, and core regions of the genome. Conclusion The immunoprophylactic failure rate in infants born to HBV-infected mothers is low in the regions of China examined during this study. Moreover, HBV mutation in the 'a' determinant region could not account for immunoprophylactic failure for all infants. 展开更多
关键词 mother-to-infant transmission scheduled vaccination Gene characteristics 'a' determinantmutation Immune escape
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甘肃积石山 M_(s)6.2级地震的震害特征与启示 被引量:1
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作者 王丽丽 王兰民 +5 位作者 卢育霞 许世阳 夏晓雨 盖海龙 池佩红 郭梅 《世界地震工程》 北大核心 2024年第1期58-71,共14页
2023年12月18日,甘肃省临夏回族自治州积石山保安族东乡族撒拉族自治县(35.70°N,102.79°E)发生了6.2级地震,震中烈度为VIII度。地震发生后,通过实地烈度评估与科学考察,对震区VI~VIII度区不同建(构)筑物与生命线工程的震害特... 2023年12月18日,甘肃省临夏回族自治州积石山保安族东乡族撒拉族自治县(35.70°N,102.79°E)发生了6.2级地震,震中烈度为VIII度。地震发生后,通过实地烈度评估与科学考察,对震区VI~VIII度区不同建(构)筑物与生命线工程的震害特点进行了统计分析;从抗震设计与施工管理、场地放大效应与地震次生灾害对建筑结构抗震性能的影响等角度,提出了此次地震的震害启示。结果表明:1)严重破坏和毁坏的建筑结构主要集中在老旧的土木结构、砖木结构和无设防或设防不规范的砖混结构。2)造成建筑结构破坏的主要原因是少量自建房抗震设计和施工的不规范、场地放大效应和地震次生灾害。3)优化和改良生土砌筑材料,改进纵横墙间的拉结措施,强化结构整体性是提高土木结构抗震的有效方法;普及“上下圈梁与构造柱”等基本抗震设防措施,规范水泥砂浆强度,提升农村工匠的施工水平,可有效提高砌体结构的整体性,避免房屋出现整体性垮塌;室内洗手间的墙体应该与房顶、纵横墙间建立有效联接,提高结构的抗震性能。4)孤突斜坡、河流高阶地与岸边为抗震不利地带。当建造用地极为匮乏,不得不选址在这些场地之上时,应该综合考虑场地的地形地貌特征、岩土体物理力学特性、水文地质条件、抗震设防目标、建筑结构类型等影响因素,做好地震灾害风险评估,根据评估结果进行科学设防。灾后重建过程中,应由政府统一规划选址、统一设计,规范施工。 展开更多
关键词 积石山6.2级地震 震害调查 场地放大效应 黄土液化流滑 震害特征
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改变导叶翼型对水泵水轮机“S”特性的影响
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作者 李琪飞 谢耕达 +1 位作者 韩天丁 李正贵 《排灌机械工程学报》 CSCD 北大核心 2024年第1期1-7,共7页
针对水泵水轮机“S”特性区域的不稳定性问题,提出使用改型活动导叶翼型进行性能提升.以某水泵水轮机模型为研究对象,采用SST k-ω湍流模型对水泵水轮机全流道进行三维数值计算,通过对活动导叶翼型的改型设计,得出流量-转速模拟曲线,分... 针对水泵水轮机“S”特性区域的不稳定性问题,提出使用改型活动导叶翼型进行性能提升.以某水泵水轮机模型为研究对象,采用SST k-ω湍流模型对水泵水轮机全流道进行三维数值计算,通过对活动导叶翼型的改型设计,得出流量-转速模拟曲线,分析水泵水轮机组“S”特性改善情况.将计算与试验结果进行对比,并对改型活动导叶翼型前后机组的无叶区进行压力脉动分析.结果表明:在保证整体效率依然保持在92%附近的前提下,新的活动导叶翼型对机组的“S”特性依旧具有改善效果;无叶区压力脉动主要是受到活动导叶叶栅区域的分流在此重新聚集影响,并且与转轮叶片的动静相互扰动引起的;改型后的活动导叶降低了无叶区的压力脉动幅值,提升了水泵水轮机运行中的并网稳定性. 展开更多
关键词 水泵水轮机 s”特性曲线 活动导叶 翼型设计 数值计算
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电液3-UPS/S并联稳定平台参数振动特性分析
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作者 袁晓明 王维锜 +1 位作者 庞浩东 张立杰 《振动与冲击》 EI CSCD 北大核心 2024年第5期52-61,共10页
针对电液3-UPS/S并联稳定平台驱动液压缸的压力脉动所产生的参数振动,建立了稳定平台的参数振动方程并利用多尺度法求解了主共振响应与组合共振响应的一次近似解;分析了主共振与组合共振响应特性以及振动幅值在初始工作空间内的变化规律... 针对电液3-UPS/S并联稳定平台驱动液压缸的压力脉动所产生的参数振动,建立了稳定平台的参数振动方程并利用多尺度法求解了主共振响应与组合共振响应的一次近似解;分析了主共振与组合共振响应特性以及振动幅值在初始工作空间内的变化规律,最后采用四阶龙格库塔法与模态试验对参数振动模型进行验证。结果表明:数值解与理论解之间的最大误差为4.20%,固有频率理论值与试验值之间的最大误差为4.66%,可验证参数振动模型的正确性。 展开更多
关键词 电液3-UPs/s并联稳定平台 压力脉动 参数振动 多尺度法 振动特性
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Isolation and algae-lysing characteristics of the algicidal bacterium B5 被引量:30
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作者 MU Rui-min FAN Zheng-qiu +3 位作者 PEI Hai-yan YUAN Xue-liang Liu Si-xiu WANG Xiang-rong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第11期1336-1340,共5页
Water blooms have become a worldwide environmental problem. Recently, algicidal bacteria have attracted wide attention as possible agents for inhibiting algal water blooms. In this study, one strain of algicidal bacte... Water blooms have become a worldwide environmental problem. Recently, algicidal bacteria have attracted wide attention as possible agents for inhibiting algal water blooms. In this study, one strain of algicidal bacterium B5 was isolated from activated sludge. On the basis of analysis of its physiological characteristics and 16S rDNA gene sequence, it was identified as Bacillusfusiformis. Its algaelysing characteristics on Microcystis aeruginosa, Chlorella and Scenedesmus were tested. The results showed that: (1) the algicidal bacterium B5 is a Gram-negative bacterium. The 16S rDNA nucleotide sequence homology of strain B5 with 2 strains of B. fusiformis reached 99.86%, so B5 was identified as B. fusiformis; (2) the algal-lysing effects of the algicidal bacterium B5 on M. aeruginosa, Chlorella and Scenedesrnus were pronounced. The initial bacterial and algal cell densities strongly influence the removal rates of chlorophyll-a. The greater the initial bacterial cell density, the faster the degradation of chlorophyll-a. The greater the initial algal cell density, the slower the degradation of chlorophyll-a. When the bacterial cell density was 3.6 × 10^7 cells/ml, nearly 90% of chlorophyll-a was removed. When the chlorophyll-a concentration was less than 550 μg/L, about 70% was removed; (3) the strain B5 lysed algae by secreting metabolites and these metabolites could bear heat treatment. 展开更多
关键词 algicidal bacteria water blooms algae-lysing characteristic 16s rDNA Bacillusfusiformis
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Kinematic and Dynamic Characteristics Analysis of Bennett's Linkage 被引量:5
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作者 Changjian Zhi Sanmin Wang +1 位作者 Yuantao Sun Jianfeng Li 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第3期95-100,共6页
Bennett's linkage is a spatial fourlink linkage,and has an extensive application prospect in the deployable linkages.Its kinematic and dynamic characteristics analysis has a great significance in its synthesis and... Bennett's linkage is a spatial fourlink linkage,and has an extensive application prospect in the deployable linkages.Its kinematic and dynamic characteristics analysis has a great significance in its synthesis and application. According to the geometrical conditions of Bennett 's linkage,the motion equations are established,and the expressions of angular displacement,angular velocity and angular acceleration of the followers and the displacement,velocity and acceleration of mass center of link are shown. Based on Lagrange's equation,the multi-rigid-body dynamic model of Bennett's linkage is established. In order to solve the reaction forces and moments of joint,screw theory and reciprocal screw method are combined to establish the computing method.The number of equations and unknown reaction forces and moments of joint are equal through adding link deformation equations. The influence of the included angle of adjacent axes on Bennett 's linkage 's kinematic characteristics,the dynamic characteristics and the reaction forces and moments of joint are analyzed.Results show that the included angle of adjacent axes has a great effect on velocity,acceleration,the reaction forces and moments of Bennett's linkage. The change of reaction forces and moments of joint are apparent near the singularity configuration. 展开更多
关键词 bennett’s linkage kinematic characteristics dynamic characteristics Lagrange’s equations screw theory reciprocal screw method
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RITT-WU'S CHARACTERISTIC SET METHOD FOR ORDINARY DIFFERENCE POLYNOMIAL SYSTEMS WITH ARBITRARY ORDERING 被引量:4
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作者 高小山 袁春明 张桂林 《Acta Mathematica Scientia》 SCIE CSCD 2009年第4期1063-1080,共18页
In this paper, a Ritt-Wu's characteristic set method for ordinary difference systems is proposed, which is valid for any admissible ordering. New definition for irreducible chains and new zero decomposition algorithm... In this paper, a Ritt-Wu's characteristic set method for ordinary difference systems is proposed, which is valid for any admissible ordering. New definition for irreducible chains and new zero decomposition algorithms are also proposed. 展开更多
关键词 difference polynomial ascending chain characteristic set Ritt-Wu's zero decomposition theorem
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水泵水轮机S特性区能量损失及流动特性研究
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作者 王李科 姚亮 +3 位作者 冯建军 朱国俊 卢金玲 阮辉 《水利学报》 EI CSCD 北大核心 2024年第3期344-354,366,共12页
为了调节电网的稳定性,抽水蓄能电站需要频繁启停和变换工况运行,导致水泵水轮机容易进入S特性区,机组振动增加,并网失败。本文以模型水泵水轮机为研究对象,采用熵产理论详细分析了S特性区不同工况下的能量损失规律,明确了熵产率分布与... 为了调节电网的稳定性,抽水蓄能电站需要频繁启停和变换工况运行,导致水泵水轮机容易进入S特性区,机组振动增加,并网失败。本文以模型水泵水轮机为研究对象,采用熵产理论详细分析了S特性区不同工况下的能量损失规律,明确了熵产率分布与内部流动结构的关系。结果表明:S特性区内近飞逸工况总熵产最大,约为设计工况的5.1倍,脉动熵产占据的比例接近80%,随着流量的减小,转轮熵产占比逐渐降低,活动导叶和尾水管的熵产占比增加。小流量工况转轮进口靠近下环位置首先出现了明显的漩涡,导致了活动导叶出口和转轮进口的高熵产区,随着流量进一步减小,漩涡逐渐向上冠转移,并且切向速度增大,在转轮进口形成挡水环,阻碍水流进入转轮,在无叶区内出现了环状分布的高熵产区。反水泵工况,水流在低压边与逆时针旋转的叶片撞击,导致水流很难进入叶片内部,形成了大尺度的回流涡结构;双列叶栅内充满大量涡结构,导致活动导叶吸力面的熵产率增大,并且向固定导叶传播。 展开更多
关键词 水泵水轮机 s特性 熵产理论 回流涡
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Effects of Drought Stress Simulated by Polyethylene Glycol on Seed Germination, Root and Seedling Growth, and Seedling Antioxidant Characteristics in Job’s Tears 被引量:3
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作者 Can Wang Lingbo Zhou +5 位作者 Guobing Zhang Yan Xu Xu Gao Ne Jiang Liyi Zhang Mingbo Shao 《Agricultural Sciences》 2018年第8期991-1006,共16页
Two Job’s tears cultivars, yy18-1 (high resistance to drought stress) and yy12-7 (susceptible to drought stress) were used to investigate the responses of seed germination, root and seedling growth, and seedling anti... Two Job’s tears cultivars, yy18-1 (high resistance to drought stress) and yy12-7 (susceptible to drought stress) were used to investigate the responses of seed germination, root and seedling growth, and seedling antioxidant characteristics to drought stress simulated by polyethylene glycol (PEG) 6000 solutions with 0, -0.05, -0.1, -0.15, and -0.2 MPa osmotic potentials. The results showed that the germination energy, germination rate, germination index, root and seedling lengths, root and seedling diameters, root and seedling fresh masses, root and seedling dry masses, and seedling relative water content (RWC) decreased with the decrease of the osmotic potential of PEG 6000 solution. The contents of hydrogen peroxide (H2O2), malondialdehyde (MDA), and proline in seedling increased with the decrease of the osmotic potential of PEG 6000 solution. The activities of peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase (GR) in seedling increased and then decreased with the decrease of osmotic potential of PEG 6000 solution. -0.1 MPa was the optimal osmotic potential of PEG 6000 solution simulated drought stress at germination stage for Job’s tears. The proline content and activities of POD and CAT were important mechanisms for the maintenance of drought resistance in Job’s tears seedling. 展开更多
关键词 ANTIOXIDANT characteristics Drought stress Germination GROWTH Job’s TEARs Polyethylene GLYCOL
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基于TDLAS的H_(2)S气体材料表面吸附特性研究
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作者 金建新 刘威 +3 位作者 宋振明 朱志辉 田冰 彭志敏 《激光与红外》 CAS CSCD 北大核心 2024年第5期710-717,共8页
在H_(2)S气体浓度在线监测过程中,因其具有粘附性强的特点,容易发生管线吸附,从而导致测量结果存在偏差,尤其在痕量H_(2)S检测过程中表现最为明显,所以开展H_(2)S气体管线材料表面吸附特性研究尤为必要。本文基于可调谐二极管激光吸收... 在H_(2)S气体浓度在线监测过程中,因其具有粘附性强的特点,容易发生管线吸附,从而导致测量结果存在偏差,尤其在痕量H_(2)S检测过程中表现最为明显,所以开展H_(2)S气体管线材料表面吸附特性研究尤为必要。本文基于可调谐二极管激光吸收光谱技术(TDLAS),设计并搭建了一套H_(2)S浓度在线测定系统,并对该系统进行了测量性能检验,在此基础上进行了H_(2)S在不锈钢材料表面常温吸附特性探究。实验结果表明,所搭建H_(2)S浓度在线测定系统具有稳定性强、检测限低和灵敏度高的特点,利用此系统可以实现痕量H_(2)S浓度的在线连续测定。经过一系列探究试验,证明了H_(2)S在不锈钢材料表面存在明显且稳定的吸附作用,得出了H_(2)S在不锈钢材料表面的单位面积吸附量在10^(14)(个/cm^(2))量级。实验结果可以为痕量硫化氢在线精准测量提供一定参考。 展开更多
关键词 TDLAs H_(2)s 测量系统 材料表面 吸附特性
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基于射流补水的水泵水轮机S特性改善研究
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作者 胡加琨 周大庆 +2 位作者 王胤淞 陈会向 郭俊勋 《水电能源科学》 北大核心 2024年第1期166-169,165,共5页
针对水泵水轮机的“S”特性提出了在导叶顶盖位置无叶区处加装注水管的解决方案,并模拟了注水管安装在不同位置时的“S”特性曲线,分析了加装注水管后转轮区域内流线及转轮各叶道流量的分布规律。结果表明,于导叶顶盖加装注水管可以有... 针对水泵水轮机的“S”特性提出了在导叶顶盖位置无叶区处加装注水管的解决方案,并模拟了注水管安装在不同位置时的“S”特性曲线,分析了加装注水管后转轮区域内流线及转轮各叶道流量的分布规律。结果表明,于导叶顶盖加装注水管可以有效改善转轮内部流动,减轻转轮和导叶内部流动的相互影响,减小叶道涡的尺寸,同时有效缓解了转轮各叶道流量分布不均的现象。在注水管处于无叶区中段和活动导叶附近时,对“S”特性的改善效果明显。 展开更多
关键词 s”特性 水泵水轮机 射流补水 注水管
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SSTA SIGNAL CHARACTERISTIC ANALYSIS OVER THE INDIAN OCEAN DURING RAINY SEASON IN CHINA 被引量:1
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作者 晏红明 严华生 谢应齐 《Journal of Tropical Meteorology》 SCIE 2001年第2期122-130,共8页
The teleconnection distribution characteristics of sea surface temperature (SST) over the India Ocean and the precipitation during rainy season in China were studied by using the methods of EOF and CCA. The results in... The teleconnection distribution characteristics of sea surface temperature (SST) over the India Ocean and the precipitation during rainy season in China were studied by using the methods of EOF and CCA. The results indicate that the change of SST field will affect the change of rain belt during rainy seasons in China, and greatly affect the precipitation in northwest and southwest China, the Yangzi and Yellow River downstream basins. Strong signal phenomena of SSTA over India Ocean were revealed that showed the anoma-lous distribution of drought and flood in China. It shows that the precipitation during rainy seasons in China may be forecast by analyzing SST distribution characteristics over the India Ocean. 展开更多
关键词 precipitation in China’s RAINY sEAsON ssTA CANONICAL correlation analysis signal characteristics
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Comparison of the Quality Characteristics of 4 Albinos Tea 被引量:1
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作者 Ronglin Li Zhengzheng Li +2 位作者 Yiyang Yang Hao Yuan Yunlong Kong 《Food and Nutrition Sciences》 2013年第11期1102-1107,共6页
The made tea quality and chemical characteristics of 4 albinos cultivars were investigated. It shows that constitutes of micro-elements, contents of polyphenols and total amino acids in 4 samples are much different du... The made tea quality and chemical characteristics of 4 albinos cultivars were investigated. It shows that constitutes of micro-elements, contents of polyphenols and total amino acids in 4 samples are much different due to the biological diversity. The DPPH free radicals scavenging ability of the 4 albinos tea is also different. The free radicals scavenging rate has a significant positive correlation to the content of total polyphenols, total catechins, as well as C, CG, GCG, EGCG, but there is no positive relationship to the content of Zn, Se. 展开更多
关键词 Albino’s TEA CHEMICAL characteristics DIVERsITY
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Geochemical characteristics and growth suitability assessment of Scutellaria baicalensis Georgi in the Earth's critical zone of North China 被引量:1
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作者 LI Xia WEI Xiao-feng +4 位作者 WU Jin YIN Zhi-qiang WAN Li-qin SUN Hou-yun AN Yong-long 《Journal of Mountain Science》 SCIE CSCD 2022年第5期1245-1262,共18页
Geochemical differentiation of soils has a series of consequences on plant and places pressure on the ecological environment.The quantitative evaluation of element migration in the Earth’s critical zone is a challeng... Geochemical differentiation of soils has a series of consequences on plant and places pressure on the ecological environment.The quantitative evaluation of element migration in the Earth’s critical zone is a challenging task.In this study,two demonstration study areas of Scutellaria baicalensis Georgi were selected,and multiple chemical weathering indexes,chemical loss fraction,mass migration coefficients and biological enrichment coefficient method were used to assess the ecological and geochemical suitability.The results show that for the element of Fe,Zn,Se,Cu,Co,Ni,Mo and Ge,the degree of weathering and soil maturation,were greater in the rhyolitic tuff area than in the Plagioclase gneiss area.In both research sites,the heavy metal level of samples in Scutellaria baicalensis Georgi did not exceed the standard limits.The plagioclase gneiss region’s surface soil environment was more alkaline,and the content of soil organic matter was lower,resulting in a higher bioenrichment intensity of Ge,Co,Cu,and Se elements in Scutellaria baicalensis Georgi than in the rhyolite-tuff area.The elements of Cd,Nb,Mo,Pb and As are considerably enriched in the soil of the plagioclase gneiss area but lost by leaching in the soil of the rhyolite tuff area,which is connected to the interplay of elemental abundance and human impact in the parent materials.This study provides a good example of how to assess growth suitability of Chinese medicinal materials in the Earth’s critical zone. 展开更多
关键词 Earth’s critical zone Biogeochemistry characteristics Weathering mechanism Element migration Chinese medicinal materials Chengde
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基于Scholte波频散特性的深海海底横波速度反演
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作者 于鹏飞 江佳萌 +1 位作者 耿建华 张宝金 《Applied Geophysics》 SCIE CSCD 2024年第1期13-30,203,共19页
深海环境下海水的声波速度是非匀速的,变速的海水会影响海底Scholte波的频散特性,为了提高利用Scholte波频散特性反演海底横波速度的精度,需建立速度连续变化的水平分层海水-分层海底(HLSLS)模型。本文基于波动理论推导HLSLS模型Scholt... 深海环境下海水的声波速度是非匀速的,变速的海水会影响海底Scholte波的频散特性,为了提高利用Scholte波频散特性反演海底横波速度的精度,需建立速度连续变化的水平分层海水-分层海底(HLSLS)模型。本文基于波动理论推导HLSLS模型Scholte波频散方程和振幅深度方程。然后,基于南海海水声速剖面和实际海底弹性介质参数,分析深海环境海水速度变化对Scholte波频散特性的影响。最后,将方法用于南海深水OBS地震数据反演得到一条二维海底横波速度剖面,反演结果很好的指示了海底天然气水合物储层的分布。结果表明:深海环境下,利用海底OBS数据中的Scholte波反演海底浅层横波速度结构是可行的,南海实际深水OBS数据应用进一步验证了方法的准确性和实用性。 展开更多
关键词 scholte波 频散特性 变速海水 OBs 横波速度反演
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On Characteristics and Cultures of the Hakka's Enclosed Houses in South Jiangxi Province 被引量:1
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作者 XIONG Jianxin LI Wenqin 《Journal of Landscape Research》 2012年第12期43-46,共4页
General situation and distribution of round houses of the Hakka in south Jiangxi were introduced, such architectural styles as enclosed house with a square yard (kouzi wei, in the shape of 口), enclosed house with a y... General situation and distribution of round houses of the Hakka in south Jiangxi were introduced, such architectural styles as enclosed house with a square yard (kouzi wei, in the shape of 口), enclosed house with a yard of three transverse and one longitudinal constructions (guozi wei, in the shape of 国), and enclosed house with a round house in its yard (tao wei) were taken to analyze features of the Hakka's enclosed houses. It was highlighted that the Hakka's enclosed houses in south Jiangxi has diversified architectural styles and outstanding defensive and living functions. Construction art and religious culture shown by the enclosed houses were interpreted, and the branch of Han people with unique dialects, cultures, folk customs and emotional attitudes was proposed as a miniature of the culture in south Jiangxi. Moreover, it was stressed that more attention of the public and more efforts for the protection should be given to the Hakka's cultures in south Jiangxi, carriers of the locals' history over the past thousands of years. 展开更多
关键词 sOUTH Jiangxi Enclosed house Architectural characteristics the Hakka’s CULTUREs
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基于Swanson关怀理论的护理干预在早产儿母亲中的应用
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作者 黄丽玲 林梅 +5 位作者 黄芝蓉 许冬梅 黄婷 王嘉莹 马妮妮 李玉娟 《全科护理》 2024年第8期1459-1464,共6页
目的:探讨以Swanson关怀理论为框架的护理干预在早产儿母亲中的应用效果。方法:采取便利抽样法选取2022年1月-5月入住百色市某三级甲等医院新生儿重症监护室(NICU)治愈出院的40例早产儿母亲作为对照组,选取2022年6月-10月入住百色市某... 目的:探讨以Swanson关怀理论为框架的护理干预在早产儿母亲中的应用效果。方法:采取便利抽样法选取2022年1月-5月入住百色市某三级甲等医院新生儿重症监护室(NICU)治愈出院的40例早产儿母亲作为对照组,选取2022年6月-10月入住百色市某三级甲等医院NICU治愈出院的40例早产儿母亲作为试验组。对照组实施NICU常规护理,试验组在对照组干预的基础上实施基于Swanson关怀理论的护理干预,比较两组早产儿母亲干预前后疾病不确定感、希望水平、育儿胜任感得分情况。结果:干预后试验组早产儿母亲疾病不确定感得分明显低于对照组(P<0.001),希望水平得分明显高于对照组(P<0.001);出院时及出院1个月后试验组早产儿母亲育儿胜任感得分明显高于对照组(P<0.001)。结论:基于Swanson关怀理论的护理干预可有效降低早产儿母亲疾病不确定感水平,提高其希望水平,增强其育儿胜任感,有利于早产儿顺利从医院过渡至家庭。 展开更多
关键词 swanson关怀理论 早产儿母亲 疾病不确定感 希望水平 育儿胜任感量表
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Impact of the Changes in Women’s Characteristics over Time on Antenatal Health Care Utilization in Egypt (2000-2008) 被引量:1
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作者 Hassan H. M. Zaky Dina M. Armanious Mohamed Ali Hussein 《Open Journal of Obstetrics and Gynecology》 2015年第10期542-552,共11页
Objectives: This study empirically assesses the impact of the changes in women’s characteristics, empowerment, availability and quality of health services on woman’s decision to use antenatal care (ANC) and the freq... Objectives: This study empirically assesses the impact of the changes in women’s characteristics, empowerment, availability and quality of health services on woman’s decision to use antenatal care (ANC) and the frequency of that use during the period 2000-2008. Study Design: The study is a cross-sectional analytical study using 2000 and 2008 Egypt Demographic and Health Surveys. Methods: The assessment of the studied impact is conducted using the Zero-inflated Negative Binomial Regression. In addition, Factor Analysis technique is used to construct some of the explanatory variables such as women’s empowerment, the availability and quality of health services indicators. Results: Utilization of antenatal health care services is greatly improved from 2000 to 2008. Availability of health services is one of the main determinants that affect the number of antenatal care visits in 2008. Wealth index and quality of health services play an important role in raising the level of antenatal care utilization in 2000 and 2008. However, the impact of the terminated pregnancy on receiving ANC increased over time. Conclusions: Further research of the determinants of antenatal health care utilization is needed, using more updated measures of women’s empowerment, availability and quality of health services. In order to improve the provision of antenatal health care services, it is important to understand barriers to antenatal health care utilization. Therefore, it is advisable to collect information from women about the reasons for not receiving antenatal care. 展开更多
关键词 Women’s characteristics ANTENATAL Health Care Women’s EMPOWERMENT ZERO-INFLATED Negative BINOMIAL Regression EGYPT
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Analysis of the Pump-turbine S Characteristics Using the Detached Eddy Simulation Method 被引量:10
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作者 SUN Hui XIAO Ruofu +2 位作者 WANG Fujun XIAO Yexiang LIU Weichao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第1期115-122,共8页
Current research on pump-turbine units is focused on the unstable operation at off-design conditions, with the characteristic curves in generating mode being S-shaped. Unlike in the traditional water turbines, pump-tu... Current research on pump-turbine units is focused on the unstable operation at off-design conditions, with the characteristic curves in generating mode being S-shaped. Unlike in the traditional water turbines, pump-turbine operation along the S-shaped curve can lead to difficulties during load rejection with unusual increases in the water pressure, which leads to machine vibrations. This paper describes both model tests and numerical simulations. A reduced scale model of a low specific speed pump-turbine was used for the performance tests, with comparisons to computational fluid dynamics(CFD) results. Predictions using the detached eddy simulation(DES) turbulence model, which is a combined Reynolds averaged Naviers-Stokes(RANS) and large eddy simulation(LES) model, are compared with the two-equation turbulence mode results. The external characteristics as well as the internal flow are for various guide vane openings to understand the unsteady flow along the so called S characteristics of a pump-turbine. Comparison of the experimental data with the CFD results for various conditions and times shows that DES model gives better agreement with experimental data than the two-equation turbulence model. For low flow conditions, the centrifugal forces and the large incident angle create large vortices between the guide vanes and the runner inlet in the runner passage, which is the main factor leading to the S-shaped characteristics. The turbulence model used here gives more accurate simulations of the internal flow characteristics of the pump-turbine and a more detailed force analysis which shows the mechanisms controlling of the S characteristics. 展开更多
关键词 PUMP-TURBINE s-shaped characteristics detached eddy simulation(DEs numerical analysis
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Numerical Calculations of Aerodynamic and Acoustic Characteristics for Scissor Tail-Rotor in Forward Flight 被引量:3
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作者 Fan Feng Huang Shuilin Lin Yongfeng 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2016年第3期285-293,共9页
The aerodynamic and aeroacoustic characteristics of a scissor tail-rotor in a forward flight are numerically calculated.A novel computational fluid dynamics(CFD)model based on Navier-Stokes(N-S)equations is presented ... The aerodynamic and aeroacoustic characteristics of a scissor tail-rotor in a forward flight are numerically calculated.A novel computational fluid dynamics(CFD)model based on Navier-Stokes(N-S)equations is presented to simulate the unsteady flowfield and the aerodynamic characteristics of a scissor tail-rotor in the forward flight.Then the Farassat Formulation 1 Aderived from the FW-H equation is coupled into the CFD model in order to compute the aeroacoustic characteristics of the scissor tail-rotor.In addition,two different scissor tail-rotor configurations,i.e.,the L-and U-configuration,are analyzed in details and compared with a conventional one.The influence of scissor angles on the aerodynamic and aeroacoustic characteristics of the scissor tail-rotor is also investigated.The simulation results demonstrate that the flowfield,aerodynamic force and aeroacoustic characteristics of a scissor tail-rotor are significantly different from the conventional one,and the aerodynamic interaction decreases with the increase of scissor angle,which leads to a reduction of amplitude variation of the tail-rotor thrust in the forward flight.The scissor angle has an important effect on the aerodynamics and aeroacoustics of the scissor tail-rotor. 展开更多
关键词 computational fluid dynamics(CFD) scissor tail-rotors aerodynamic characteristics aeroacoustic characteristics Navier-stokes(N-s)equations
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