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Extraction kinetics of zinc by new extractant in ammoniacal system

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Journal of Central South University 2013年第7期20卷 1797-1804页

作者： HUANG Ling HE Jing chen yong-ming YANG Sheng-hai JIN Sheng-ming TANG Mo-tang School of Metallurgical Science and Engineering Central South University Changsha 410083 China Guangzhou Research Institute of Non-ferrous Metals Guangzhou 510000 China

The controlling step and the extraction reaction rate equation of zinc extraction from Zn（II）-NH3 solution by using a newly synthesized organic compound, 2-acetyl-3-oxo-dithiobutyric acid-myristyl ester as the zinc extractant, were clarified. The effects of agitation speed, specific interfacial area, temperature, extractant concentration and Zn ion concentration on the extraction rate are studied in constant interfacial area cell. The results show that the extraction rate depends on interfacial chemical reaction and diffusion by using this new extraetant to extract zinc, and the apparent activation energy of this extraction reaction is measured as 28.2 kJ/mol, which demonstrates that the extraction reaction is controlled by the mixed-controlled reaction rate. The apparent reaction orders a and b are measured as 1 and 0.38, and the constant k0 is 138.70. So, when extraction conditions are controlled as [HR]=20%-50%, T=0-30℃, N=120-177 r/min and S=72.6-127.5 m-1, the solvent extraction reaction rate can be depicted as v/（mol . m-2 . s-1 ） = 138.7. exp（ - 28 206/8.314T ）. [Zn 2＋ ]r ·[HR ]o0.38.

关键词： solvent extraction zinc 2-acetyl-3-oxo-dithiobutyric acid-myristyl ester kinetics

Gene expression profile analyses of mice livers injured by Leigongteng

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World Journal of Gastroenterology 2007年第26期13卷 3619-3624页

作者： yong chen, Xiao-ming Zhang Feng-Mei Han Peng Du Qi-Song Xia Hubei Provincial Key Laboratory of Traditional Chinese Medicine & Biotechnology School of Life Science Hubei University Wuhan 430062 Hubei Province China

AIM： To analyze the gene expression profiles of mice livers injured by Leigongteng and explore the relationship between the differentially expressed genes and liver damage. METHODS： The experimental mice were randomly divided into a control group and a liver-injured group in which the mice were administrated 33 μγ, of triptolide/ kg per day for 30 d. Liver mRNAs were extracted from animals in both groups and were reverse-transcribed to cDNA with dUTP labeled by different fluorescence （Cy3, Cy5） as hybridization probes. The mixed probes were hybridized with oligonucleotide microarray chips. The fluorescent signal results were acquired by scanner and analyzed with software. RESULTS： Among the 35852 target genes, 29 genes were found to be significantly differentially expressed, with 20 genes up-regulated and 9 genes down-regulated. The reliability of the differentially expressed genes was validated by RT-PCR experiments of 5 randomly selected differentially expressed genes. CONCLUSION： Based on the biological functions of the differentially expressed genes, it is obvious that the occurrence and development of liver damage induced by Leigongteng in mice are highly associated with immune response, metabolism, apoptosis and the cell skeleton of liver cells. This might be important for elucidating the regulatory network of gene expression associated with liver damage and it may also be important for discovering the pathogenic mechanisms of liver damage induced by Leigongteng.

关键词： Tripterygium Wilfordii Hook.f. Gene expre-ssion profile Oligonucleotide microarray Mice

Mechanics model and numerical analysis of floor heave in soft rock roadway

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Journal of Coal Science & Engineering(China) 2011年第4期17卷 372-376页

作者： ZHU Chuan-qu WANG yong chen Miao-ming chen Zhi WANG Hong-ming Hunan Key Laboratory of Safe Mining Techniques of Coal Mines Hunan University of Science and Technology Xiangtan411201 China

The mechanism of floor heave was analyzed by establishing mechanics models and solving differential equations. The amount of floor heave is proportional to the abutment pressure of surrounding rock, roadway width, and the distance of support pressure peak to the roadway and is inversely proportional to the elastic modulus of floor rock. Using FLAC2D to simulate floor rock grouting in soft rock roadway verifies the active role of floor rock grouting in the floor controlling of soft rock roadway; floor rock grouting and grouting range directly impact on the stability scope of surrounding rock, namely, with the increase of grouting range, the subsidence of roof, the approach of both sides, and the amount of floor heave decreased gradually, the stability of surrounding rock is enhanced

关键词： soft rock roadway floor heave floor rock grouting numerical simulation

Review of Surface Plasmon Resonance and Localized Surface Plasmon Resonance Sensor

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Photonic Sensors 2012年第1期2卷 37-49页

作者： yong chen Hai ming Department of Optics & Optical Engineering Anhui Key Laboratory of Optoelectronic Science and Technology University of Science and Technology of China Hefei Anhui 230026 China

An overview of recent researches of surface plasmon resonance （SPR） sensing technology in Laboratory of Science and Technology of Micro-Nano Optics （LMNO）, University of Science and Technology of China, is presented. Some novel SPR sensors, such as sensors based on metallic grating, metal-insulator-metal （MIM） nanoring and optical fiber, are designed or fabricated and tested. The sensor based on localized surface plasmon resonance （LSPR） of metallic nanoparticles is also be summarized. Because of the coupling of propagating surface plasmons and localized surface plasmons, the localized electromagnetic field is extremely enhanced, which is applied to surface-enhanced Raman scattering （SERS） and fluorenscence enhancement. Future prospects of SPR and/or LSPR sensing developments and applications are atso discussed.

关键词： Surface plasmons resonance localized surface plasmon resonance sensor electromagnetic-fieldenhancement high sensitivity

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灰色样条绝对关联度模型

系统工程理论与实践 2015年第5期35卷 1304-1310页

作者：陈勇明张明成都信息工程学院应用数学学院成都610225

灰色绝对关联度的计算基于用序列对应的折线来近似描述系统的行为特征量.从插值的角度看,折线即分段线性插值,其局限之一在于节点处不具有光滑性而真实轨迹曲线在采样点一般是光滑的;局限之二在于系统轨迹曲线曲率大时折线近似的误差相... 详细信息

灰色绝对关联度的计算基于用序列对应的折线来近似描述系统的行为特征量.从插值的角度看,折线即分段线性插值,其局限之一在于节点处不具有光滑性而真实轨迹曲线在采样点一般是光滑的;局限之二在于系统轨迹曲线曲率大时折线近似的误差相应增大,由于灰色系统研究对象为少数据贫信息系统,从而折线不能逼近真实轨迹曲线.为此,提出灰色样条绝对关联度模型以改进灰色绝对关联度,先用具有优良光滑性且近似效果好的三次样条插值函数来获得描述系统行为特征量的曲线,然后通过积分计算绝对关联度.讨论了灰色样条绝对关联度的性质和适用范围,灰色样条绝对关联度尤其适用于生长曲线类系统的关联分析,此外其可直接应用于不等时距序列.

关键词：灰色系统灰色关联度灰色绝对关联度折线三次样条插值灰色样条绝对关联度

Solution behavior of ZnS and ZnO in eutectic Na_2CO_3-NaCl molten salt used for Sb smelting

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Journal of Central South University 2017年第6期24卷 1269-1274页

作者： YE Long-gang HU Yu-jie XIA Zhi-mei TANG Chao-bo chen yong-ming TANG Mo-tang School of Metallurgical Engineering Hunan University of Technology School of Metallurgy and Environment Central South University

The solution behavior, including solubility, reactivity and sedimentation, of ZnO and ZnS in a Na2CO3−NaCl molten salt used for Sb smelting was investigated in the temperature range of 700-1000 ºC. The saturated amount of dissolved ZnO in the molten salt remained constant at 0.02% and was unaffected by temperature; additionally, ZnO did not react with the molten salt. In contrast, the saturated amount of dissolved ZnS in the eutectic molten salt increased with increasing temperature, and the content of ZnS was 0.53% at 1000 ºC. In addition, ZnS reacted with Na2CO3 above 900 ºC to give ZnO. The sedimentation rates of these three species in the molten salt followed the order of Sb>ZnS>ZnO. It was thus concluded that ZnO is an appropriate sulfur-fixing agent for low-temperature Sb smelting in a Na2CO3−NaCl molten medium, and that the optimal smelting temperature is below 900 ºC.

关键词： solubility molten salt sulfur-fixing smelting sedimentation

基于遗传算法的近红外光谱橄榄油产地鉴别方法研究

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光谱学与光谱分析 2009年第3期29卷 671-674页

作者：陈永明林萍何勇浙江大学生物系统工程与食品科学学院浙江杭州310029

提出了一种应用近红外光谱技术快速无损鉴别橄榄油产地的新方法。采用近红外光谱仪获取三种不同产地的橄榄油各30个样本的光谱漫反射特征曲线,利用全局搜索算法-遗传算法提取特征波长,即从光谱751个波长数据提取9个特征波长数据,并将其... 详细信息

提出了一种应用近红外光谱技术快速无损鉴别橄榄油产地的新方法。采用近红外光谱仪获取三种不同产地的橄榄油各30个样本的光谱漫反射特征曲线,利用全局搜索算法-遗传算法提取特征波长,即从光谱751个波长数据提取9个特征波长数据,并将其作为主成分分析法的输入变量,运用主成分分析法建立分析校正模型。结果表明,主成分1和2累计可信度已达99.130%,对不同产地的橄榄油有很好的聚类作用,同时也说明遗传算法抽取特征波长方法正确。将提取到的六种主成分作为BP神经网络的输入变量,品种类型作为神经网络的输出变量,建立3层人工神经网络模型,对30个未知橄榄油产地进行预测,预测结果准确率达100%。该方法能快速无损地检测橄榄油产地,同时也为其他油类产地鉴别提供了一种新方法。

关键词：产地橄榄油近红外光谱遗传算法主成分分析 BP神经网络

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基于可见近红外光谱的糖类别快速鉴别研究

光谱学与光谱分析 2009年第2期29卷 382-385页

作者：林萍陈永明何勇浙江大学生物工程与食品科学学院浙江杭州310029

提出了一种用近红外光谱技术快速鉴别糖类别的新方法。采用近红外光谱获取白砂糖、木糖醇、双歧糖和葡萄糖等四种糖类别的光谱反射特征曲线,采用偏最小二乘法进行模式特征分析,经过交互验证法判别,确定最佳主成分数为11。完成特征提取后... 详细信息

提出了一种用近红外光谱技术快速鉴别糖类别的新方法。采用近红外光谱获取白砂糖、木糖醇、双歧糖和葡萄糖等四种糖类别的光谱反射特征曲线,采用偏最小二乘法进行模式特征分析,经过交互验证法判别,确定最佳主成分数为11。完成特征提取后,将11种主成分作为神经网络的输入变量,建立了3层BP神经网络。四个类别的糖样本数均为40,共计160个样本,将其分成训练集样本120个和预测集样本40个,对40个未知样本进行预测,准确率为100%。说明所提出的方法对于糖类别具有很好的分类和鉴别能力。

关键词：偏最小二乘法 BP神经网络糖光谱技术

In vivo and in vitro chondrotoxicity of ciprofloxacin in juvenile rats

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Acta Pharmacologica Sinica 2004年第10期 22-26页

作者： Ping LI, Neng-neng chenG, Bin-yan chen, yong-ming WANG Department of Pharmacology, School of Pharmacy, Fudan University, Shanghai 200032, China

AIM: To study the relationship between chondrotoxicity and toxicokinetics of ciprofloxacin (CPFX). METHODS: Rats, 4-week old, were treated with CPFX 0, 400, 800, and 1200 mg/kg ig once daily on seven consecutive days. The knee joint cartilage was examined histopathologically. The concentration of CPFX in venous blood and knee joint cartilage samples were determined by a microbioassay using Escherichia coli 44102. The effects of CPFX on proliferation of chondrocytes and secretion of soluble proteoglycans were determined with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and 1,9-dimethylmethylene blue (DMB) assay, respectively. RESULTS: Cartilage was severely lesioned after treatment with CPFX 800 or 1200 mg/kg for 7 d, such as matrix swelling and loss of chondrocytes. The thickness of cartilage was significantly decreased compared with the control group. The maximum serum concentration (Cmax), the area under the plasma concentration-time curve (AUC0-∞2), and concentration in cartila

关键词： ciprofloxacin knee joints articular cartilage glycosaminoglycans cell survival toxicokinetics juvenile rats