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The acute lethality and endocrine effect of 1,2,3,7,8-PeCDD in juvenile goldfish (Carassius auratus) in vivo

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Journal of Environmental Sciences 2008年第2期20卷 240-245页

作者： yang yongbin LIU Zhengtao ZHENG Minghui ZHAO Yanyan WANG Liang SUN Wei XIAO Feng State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China China Research Academy of Environmental Sciences Beijing 100012 China Health Science Center Hebei University Baoding 071000 China

1,2,3,7,8-PeCDD was administrated to juvenile goldfish （Carassius auratus） by peritoneal injections to explore the acute lethality and endocrine effects of 1,2,3,7,8-PeCDD in vivo. The value of acute median lethal dosage （LD50） of 1,2,3,7,8-PeCDD was determined in acute lethality tests. The endocrine effect of 1,2,3,7,8-PeCDD, whose exposed concentrations were determined based on the LD50 （1.84 mg/kg）, was studied by measuring the plasma vitellogenin （Vtg） content in juvenile male goldfish with enzyme-linked immunosorbent assays （ELISA）. Due to its significant induction of the plasma Vtg after one week＇s exposure in vivo in the 1/2 LD50 and LD30 groups, 1,2,3,7,8-PeCDD might be one of the important contributors to the estrogenic effect of PCDDs in the environment. The values of 1/2 LD50 and LD30 were within the range of the effective dosages of 1,2,3,7,8-PeCDD, indicating that there was a certain relationship between the estrogenic effective dosages and the LD50.

关键词： 1,2,3,7,8-PeCDD goldfish endocrine effect vitellogenin (Vtg) acute lethality ELISA

SELECTIVE RECOVERY OF SILVER FROM AN ACIDIC SOLUTION BY CEMENTATION WITH COPPER

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Journal of Central South University 1998年第2期10卷 40-43页

作者： yongbin yang Tao Jiang Ganghua Fu Boquan He Zhucheng Huang 1. Department of Mineral Engineering Central South University of Technology 410083 Changsha China

An acidic solution containing 280 mg/l silver and others was treated. In order to selectively recover silver without losing other metallic elements from the solution, cementation was adopted with metallic copper. The kinetics of cementation reaction and copper dissolution and mechanism of copper consumption were studied. The results indicated that the rate of cementation reaction and copper consumption were markedly increased with the increase of temperature. For the same cementation recovery of silver , copper consumption at elevated temperature was much higher than that at ambient temperature . Cementation rate and copper consumption rate also increased with the increase of stirring velocity, while copper consumption at different stirring velocity for the same recovery of silver was almost not different. Studies on the chemical mechanism of copper consumption showed that Fe 3+ and residual leaching additive RH in the solution were the main factors that caused extra copper consumption in acidic solutions.

关键词： extraction cementation silver

Thoughts on the Cultivation Countermeasures of Senior Engineering Talents

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教育研究前沿（中英文版） 2014年第2期4卷 24-29页

作者： Yu yang Xiaolan Song XiQing Wu yongbin yang Tao Jiang School of Minerals Processing and Bioengineering Central South University Key Laboratory of B iometallurgy Ministry of Education Centre of Biometallurgical Engineering 932 South Lushan Road Changsha Hunan China 410083

ANODIC OXIDATION OF THIOSULFATE IONS IN GOLD LEACHING

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Journal of Central South University 1997年第2期9卷 89-91页

作者： Jiang Tao Xu Shi Chen Jin yang yongbin (Department of Mineral Engineering, Central South University of Technology, Changsha 410083, China) Department of Mineral Engineering Central South University of Technology Changsha China

The regularities of anodic oxidation of thiosulfate ions on a gold electrode have been investigated using electrochemical methods in order to improve gold extraction. Effects of ammon, copper-ammon ions, pH and sulphite on anodic oxidation of thiosulfate ions have been examined in details. Results show that the anodic oxidation of thiosulfate ions is an inreversible reaction whose oxidizing peak potential is 620 mV/SCE in the absence of ammon. Oxidation rate increases with concentration of thiosulfate ions, but not in linear relation. It is also shown that ammon has significant effects on the oxidation of thiosulfate ions by causing great decrease in oxidation rate and negative shift of peak potential. The degrees of the rate decrease and negative shift increase with ammon concentration. When ammon concentration is increased to 1. 0 mol/L, the oxidation rate decreases to one fourth of that without ammon and the peak potential shifts from 620 mV/SCE to 350 mV/SCE.

关键词： thiosulfate gold leaching anodic process electrochemistry

Studies of Differentially-Expressed Genes in Human Endometrial Cancer of Various Differentiated Grades

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Chinese Journal of Clinical Oncology 2007年第2期4卷 77-82页

作者： Bin Cai David Hogg Guangzhong Lu Ling Liu Xiaowei Xi Wei Xu Huifang Lu yongbin yang Xiaoping Wan Department of Obstetrics and Gynecology Shanghai Jiao Tong University Affiliated First People＇s Hospital Shanghai 200080 China Departments of Medicine and Medical Biophysics University of Toronto Toronto Canada Department of Pathology Shanghai Jiao Tong University Affiliated First People＇s Hospital Shanghai 200080 China

OBJECTIVE To study the gene expression profiles of human endometrial cancers at various differentia0ted grade levels and to identify the genes related to differentiation of the endometrial cancers. METHODS cDNA microarray technology was used to analyze the differentially-expressed genes among different differentiated grades of 32 cases of endometrial cancer. Hierarchical cluster analysis （HCA） for the gene expression profiles of the cases was employed. RESULTS The tissue samples were grouped based on the various differentiated tumor grades with 33 differentiation-related genes identified out （P〈0.001）. Based on the results from the HCA, the conformity rate was 91% among the 33 differentially-expressed genes, and the analysis of pathological classification.CONCLUSION Genes related to the differentiation of endometrial cancer can be identified by using gene chips to analyze the expression profiles of endometrial cancers at various differentiated grades; HCA of the gene expression profiles can be helpful for distinguishing high-risk endometrial cancers before surgery.

关键词： cDNA microarray endometrial tumor gene expression profile hierarchical cluster analysis.

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板翅式换热器瞬态法数值模拟与实验研究

西安交通大学学报 2018年第7期52卷 38-45页

作者：杨永斌厉彦忠司标西安交通大学能源与动力工程学院西安710049 西安交通大学动力工程多相流国家重点实验室西安710049

通过瞬态单吹实验和瞬态数值模拟方法对47PZ3002型板翅式换热器热力、阻力性能等进行了研究,探索了该瞬态技术在板翅式换热器性能研究中的可行性与准确性。应用瞬态单吹实验,得到了雷诺数为500~3 000工况下换热器进出口温度场随时间的... 详细信息

通过瞬态单吹实验和瞬态数值模拟方法对47PZ3002型板翅式换热器热力、阻力性能等进行了研究,探索了该瞬态技术在板翅式换热器性能研究中的可行性与准确性。应用瞬态单吹实验,得到了雷诺数为500~3 000工况下换热器进出口温度场随时间的变化值及流体流经换热器的压降。对换热器实验件建立瞬态换热物理模型,利用Visual Basic语言编写与瞬态技术配套使用的程序对实验结果进行处理,获得了流体在板翅式换热器内的对流换热系数、j因子等性能参数。通过CFD软件,模拟了与实验工况相同条件下该换热器的相应性能参数,模拟结果与实验结果j因子之间的平均偏差为4.4%,最大偏差为10.7%,f因子的平均偏差为5.37%,最大偏差为13.0%,实验验证了该瞬态技术在平直型板翅式换热器性能研究中的可靠性。该瞬态技术测量简单、效率高,在短时间内即可获得换热器的性能参数,可为板翅式换热器工程设计提供有价值的性能预测方案。

关键词：板翅式换热器瞬态技术单吹实验数值模拟

基于SNMP++和Web的网络管理系统研究

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小型微型计算机系统 1999年第6期20卷 460-463页

作者：杨波杨永斌山东建材学院网络中心

本文介绍了基于Ｗｅｂ的计算机网络管理技术，结合一个实际网管系统的开发，讨论了ＷｉｎｄｏｗｓＮＴ环境下利用ＳＮＭＰ＋＋类库开发网管软件的方法．该方法将ＳＮＭＰ，ＷＩＮＳＯＣＫ，Ｗｅｂ和ＳＱＬ结合在一起，非常适合于ＴＣＰ... 详细信息

本文介绍了基于Ｗｅｂ的计算机网络管理技术，结合一个实际网管系统的开发，讨论了ＷｉｎｄｏｗｓＮＴ环境下利用ＳＮＭＰ＋＋类库开发网管软件的方法．该方法将ＳＮＭＰ，ＷＩＮＳＯＣＫ，Ｗｅｂ和ＳＱＬ结合在一起，非常适合于ＴＣＰ／ＩＰ网络的流量控制及安全管理．

关键词： SNMP++ Web 网络管理系统计算机网络

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基于导航星间链路的天基高精度时间传递方法

中国科学：技术科学 2017年第1期47卷 71-79页

作者：郭熙业周永彬杨俊国防科学技术大学机电工程与自动化学院长沙410073

随着航天技术的不断发展,航天器的数量日益增多,迫切需要一种统一的、高性能的天基授时手段,以便为各类航天器的高效协同提供保障.导航星间链路广泛适用于卫星精密定轨与时间同步,并且覆盖了星座内的中高轨卫星,因此可作为一种理想的天... 详细信息

随着航天技术的不断发展,航天器的数量日益增多,迫切需要一种统一的、高性能的天基授时手段,以便为各类航天器的高效协同提供保障.导航星间链路广泛适用于卫星精密定轨与时间同步,并且覆盖了星座内的中高轨卫星,因此可作为一种理想的天基高精度时间传递手段.现有的导航星间链路时间同步方法依赖于导航卫星具备星历信息,并不适用于位置精度较低且空间信息缺乏完整性的任意空间飞行器.本文在导航星间链路双向测量原理的基础上,提出了一种动态条件下时延修正方法,该方法计算简单、工程可实现性强,只需要空间飞行器终端具备多普勒测量或连续伪距测量功能,即可实现空间飞行器在一般位置精度条件下的高性能时间同步.理论分析表明,授时精度优于0.1ns.最后,以地面站模拟空间飞行器,结合北斗星间链路星地实测数据开展了时间同步试验,试验结果验证了本方法的有效性.

关键词：星间链路时间传递空间飞行器双向测量动态时延修正

聚丁二酸丁二醇酯/聚乙二醇硬脂酸酯共混物结晶行为

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高分子材料科学与工程 2019年第2期35卷 91-96页

作者：黄勇刘俊红杨永斌四川理工学院化学工程学院四川自贡643000 四川化工职业技术学院化学工程系四川泸州646005

用溶液共混的方法制备了聚丁二酸丁二醇酯(PBS)/聚乙二醇硬脂酸酯(PEOST)共混物。采用差示扫描量热法(DSC)表征了共混物的结晶熔融行为。研究结果表明,加入质量分数5%的PEOST能使PBS结晶温度(T_c)降低约10℃,但使熔融温度(T_m)升高约3℃... 详细信息

用溶液共混的方法制备了聚丁二酸丁二醇酯(PBS)/聚乙二醇硬脂酸酯(PEOST)共混物。采用差示扫描量热法(DSC)表征了共混物的结晶熔融行为。研究结果表明,加入质量分数5%的PEOST能使PBS结晶温度(T_c)降低约10℃,但使熔融温度(T_m)升高约3℃,继续增加PEOST用量对PBS的T_c和T_m影响不大;PBS的结晶焓(ΔH_c)随PEOST含量的增加呈上升趋势,而熔融焓(ΔH_m)先降低再上升;PEOST的结晶属于受限结晶,当其质量分数低于10%,DSC曲线中没有出现PEOST的结晶峰和熔融峰;当质量分数大于20%时,才出现PEOST结晶峰和相应的熔融峰。傅里叶变换红外(FT-IR)谱图中也才出现相应的结晶红外响应峰(1107 cm^(-1)和841 cm^(-1))。广角X射线衍射显示加入PEOST未改变PBS的晶体结构。偏光显微镜分析表明,PEOST含量较高的共混物晶体尺寸更大,具有更清晰的周期性明暗相间的环带花纹。

关键词：聚丁二酸丁二醇酯聚乙二醇硬脂酸酯结晶行为共混物