检索结果-南通市图书馆

Formation and evolution mechanisms of large-clusters during rapid solidification process of liquid metal Al

Science china(Physics,Mechanics & Astronomy) 2005年第1期48卷 101-112页

作者： LIU Rangsu, DONG Kejun, LIU Fengxiang, ZHENG Caixing, LIU Hairong & LI Jiyong Department of Applied Physics, hunan university, changsha 410082. china college of Materials Science and {3.ing, hunan university, changsha 410082. china college of chemistry and chemical {3.ing, hunan university, changsha 410082. china 1. Department of Applied Physics Human University 410082 Changsha China 2. college of Materials Science and engineering Hunan University 410082 Changsha China 3. college of chemistry and chemical {3.ing Hunan University 410082 Changsha China

A molecular dynamics simulation study has been performed for the formation and evolution characteristics of nano-clusters in a large-scale system consisting of 400000 atoms of liquid metal Al. The center-atom method combined with pair-bond analysis technique and cluster-type index method (CTIM) has been applied here to describe the structural configurations of various basic clusters. It is demonstrated that both the 1551 bond-type and the icosahedral cluster (12 0 12 0) constructed by 1551 bond-types are dominant among all the bond-types and cluster-types, respectively, in the system and play a critical role in the microstructure transitions of liquid metal Al. The nano-clusters (containing up to 150 atoms) are formed by the combination of some middle and small clusters with distinctly different sizes, through mutual competition by unceasing annex and evolution in a seesaw manner (in turn of obtaining and losing),which do not occur as the multi-shell structures accumulated with an atom as the center and the surrounding atoms are arranged according to a certain rule. This is the essential distinction of nano-cluster in liquid metal from those obtained by gaseous deposition, ionic spray methods, and so on. Though the nano-clusters differ from each other in shape and size, all of them possess protruding corners that could become the starting points of various dendrite structures in the solidification processes of liquid metals.

关键词： liquid metal, solidification process, large-cluster configuration, evolution mechanism, computer simulation.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Inductance-based sensing technique for wireless,remote-query measurement in liquid media

引用

Science china chemistry 2010年第6期53卷 1391-1397,1460页

作者： MA Lin,NIE Zhou,HUANG Yan & YAO ShouZhou State Key Laboratory of Chemo/Biosensing and Chemometrics,college of chemistry and chemical {3.ing,hunan university,changsha 410082.china 1. State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering Hunan University Changsha 410082 China

A novel inductance-based sensing technique is presented for remote query measurement in different liquid media including organic solvents and inorganic *** inorganic solutions tested included salt solutions of different concentrations,and the organic solvents detected included 1,4-dioxane and *** extend the application of the sensor,bacterial culture media were also detected,and the growth of Escherichia coli (***) was *** influential factors which may affect the inductance responses were studied in *** was found that quantitative relationships exist between the sensor’s inductance response and the physico-chemical parameters of the liquid *** sensor’s inductance response (L) decreases with the increase of salt concentration (C) and its ionic valence (e) according to a semi-logarithmic equation LgL =-aeC + b,where a and b are constants,which is in accordance with the theoretically deduced *** inductance variation rate (ΔK) increases directly with the temperature (T): ΔK = a′ T + b′.As for organic solutions,the sensor’s inductance was found to increase with the increasing permittivity of the organic *** wireless sensor we designed is simple and easy to *** has the potential for remote determination of not only chemical substances but also microbiological species such as *** the newly developed inductance-based sensor,the pathogenic *** was monitored with a limit of detection of 10 cells/mL and a linear semi-logarithmic range of 1.0 × 101 to 2.5 × 109 cells/mL.

关键词： inductance sensor remote-query liquid medium wireless bacterial detection E. coli.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Quantitative detection of ING1 mRNA under different gene regulation based on molecular beacon

引用

Chinese Science Bulletin 2006年第17期51卷 2059-2064页

作者： LIU Bin1,2,3.4, WANG Kemin1,2,3.4, XIAO Zhiqiang5,6, WANG Wei1,3.4, TAN Weihong1,2,3.4, SUN Yi5,6, TANG Hongxing1,3.4 & YANG Xiaohai1,3.41. State Key Laboratory of Chemo/Biosensing and Chemometrics, Hu- nan university, changsha 410082. china 2. Life Science and Biotechnology Institute, hunan university, Chang- sha {3. china 3. chemistry and chemical engineer college, hunan university, changsha 410082. china 4. hunan engineering Research Center for Bio-Nanotechnology, hunan university, changsha 410082. china 5. Medical Experiment Research Center, Xiangya Hospital, Central South university, {13. 410008, china 6. Key Laboratory of Cancer Proteomics of Chinese Ministry of Health, {13. 410008, china State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan University Changsha China Life Science and Biotechnology Institute Hunan University Changsha China chemistry and chemical engineer {3. Hunan University Changsha China hunan engineering Research Center for Bio-Nanotechnology Hunan University Changsha China Medical Experiment Research Center Xiangya Hospital Central South University Changsha China Key Laboratory of Cancer Proteomics of Chinese Ministry of Health Changsha China

The effects of drug treatment, gene transfection, and p53.RNA interference (RNAi) on level of ING1 mRNA in tumor cells were quantitatively detected with the help of ING1 molecular beacon (MB)/cRNA standard curve based on MB detection technology. Results showed that the level of ING1 mRNA could be upregulated by 5-FU treatment or ING1 transfection in low expression cell line of MCF-7 and be inhibited by silencing p53.with RNAi technology in normal expression cell line of CNE2. The level of ING1 varied from 7.7×10?16 to 53.4× 10?16 mol/μg total RNA of tumor cells. The results not only provided evidence for the regulation effects of gene expression but also were applied to investigat- ing the interaction of multigenes on signal transduc- tion pathway.

关键词： ING1 RT-PCR 定量分析分子信号 mRNA

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Cell-SELEX-based aptamer-conjugated nanomaterials for enhanced targeting of cancer cells

引用

Science china chemistry 2011年第8期54卷 1218-1226页

作者： KONG RongMei, CHEN Zhuo, YE Mao, ZHANG XiaoBing & TAN WeiHong State Key Laboratory for Chemo/Biosensing and Chemometrics college of chemistry and chemical {3.ing, hunan university, changsha 410082. china 1. State Key Laboratory for Chemo/Biosensing and Chemometrics college of chemistry and chemical {3.ing Hunan University Changsha 410082 China

Early detection and treatment of cancer depends on developing highly sensitive and specific methods for targeting cancer cells. To do this, aptamers, which are generated by a novel technique caUed ceU-SELEX （systematic evolution of ligands by exponential enrichment）, have been widely applied in cancer cell targeting based on such merits as high target affinity and specificity, small size, minimal immunogenicity, and ease of chemical modification. Furthermore, aptamers can gain more flexibility as cancer cell targeting tools when conjugated to nanomaterials, including metallic nanoparticles, quantum dots, silica nanoparticles, and carbon nanomaterials, among others. In this review, we discuss the use of cell-SELEX-based aptamer-nanomaterials conjugates as novel molecular tools for enhanced targeting of cancer cells.

关键词： celI-SELEX aptamer nanomaterial cancer cells targeting

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Development of novel and sensitive sensors based on microcantilever of atomic force microscope

引用

Progress in Natural Science:Materials International 2006年第5期16卷 445-451页

作者： JIN Yan, WANG Kemin and JIN Rong (State Key Laboratory of Chemo/Biosensing and Chernometrics, Institute of Biological Technology, college of chemistry and chemical {3.ing, hunan university, changsha 410082. china) [a]State Key Laboratory of Chemo Biosensing and Chemometrics Institute of Biological Technology College of Chemistry and Chemical Engineering Human University Changsha China

Recently, the development of sensors based on microfabricated cantilevers of atomic force microscope (AFM) has attracted considerable attention from the designers of novel physical, chemical, and biological sensors. Many kinds of sensors have been developed taking the advantages of its high-resolution imaging, force measurement and force sensitivity, such as immunosensor and DNA biosensor and the sensors for detection of intermolecular interaction. This paper reviews the progress made in this field and discusses the signal transfer principles by which the design of the sensors is achieved.

关键词： atomic force microscopy microcantilever sensor.

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Synthesis and purification of trialkyl compounds of gallium and indium

引用

Rare Metals 2002年第1期21卷 1-6页

作者： SHU Wangen, ZHOU Zhongcheng and LI Xiong chemistry and chemical engineering {3., Central South university, changsha 410083. china chemistry and chemistry engineering {3. Central South University Changsha 410083 chemistry and chemical engineering {3. Central South University Changsha 410083

The The research progress in trialkyl compounds of gallium andindium was discussed from two aspect, one was the chemical synthesisof the compounds and the other was the purification of them. Thereare three synthesis routes be- ing reported in the first aspect, *** route staring form pure metal, the route starting from the puremetal trihalides, and the electrochemical route. In the secondaspect, the purifying methods of decomposition-distillation and zonerefining were reviewed.

关键词： trialkyl compounds gallium nd indium synthesis purification

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Resolution of α-cyclohexyl-mandelic acid enantiomers by two-phase (O/W) recognition chiral extraction

引用

Science china chemistry 2007年第6期50卷 764-769页

作者： TANG KeWen1,2, ZHANG GuoLi2, HUANG KeLong2, LI Yuanjian3.& YI JianMin1,2 1 Department of chemistry and chemical engineering, {3. Institute of Science and Technology, Yueyang 414000, china 2 college of chemistry and chemical engineering, Central South university, changsha 410083. china 3.college of Pharmaceutical Science, Central South university, changsha 410078, china Department of chemistry and chemical engineering Hunan Institute of Science and TechnologyYueyang 414000China college of chemistry and chemical {3.ing Central South UniversityChangsha 410083China

This paper presents a new chiral separation technology:two-phase(O/W)recognition chiral *** behavior of alpha-cyclohexyl-mandelic acid enantiomers was studied in the extraction system with D(L)-isobutyl tartrate in 1,2-dichloroethane organic phase and beta-CD derivatives in aqueous phase,and the influence of the kind and concentration of extractant and pH on extraction performance was *** experimental results indicate that two-phase(O/W)recognition chiral extraction is of strong chiral separation ***-^-CD,HE-beta-CD and Me-beta-CD have higher recognition ability for S-CHMA than that for R-CHMA,among which HP-beta-CD has the strongest ability;whereas,D-isobutyl tartrate has reversed recognition ability for *** the extraction system containing HP-beta-CD and D-isobutyl tartrate,e.e.% of S-CHMA in aqueous phase reached 27.6% by one stage extraction,and the distribution ratio for R-CHMA(k_R)and for S-CHMA(k_S)and separation factor(alpha)are 2.44,0.89 and 2.49,***,pH and concentration of extractant have great effects on chiral separation ***-phase(O/W)recognition chiral extraction has great significance for preparative separation of racemic compounds.

关键词： two-phase(W/0)recognition chiral extraction alpha-cyclohexyl-mandelic acid enantiomers

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Catalytic Acylation of Anisole over Some Zeolites

引用

chemical Research in Chinese Universities 2000年第3期16卷 191-197页

作者： ZHAO Zhen hua (college of chemistry and chemical Technology, {3. Normal university, changsha 410081, P. R. china) (Received Sept. 22, 1999) hunan Normal Univ Coll Chem & Chem Technol Changsha 410081 Peoples R China

Methoxyacetophenone(4 MAP) was synthesized by the acylation of anisole with acetic anhydride in the presence of HY zeolite. The addition of an appropriate amount of some solvent such as dichloromethane, chloroform, carbon disulfide or chlorobenzene to the reaction system can improve the yield of the acylated product to a certain extent. HY zeolite used can be recovered, and reused after being regenerated, obtaining almost the same yield of 4 MAP as the fresh zeolite.

关键词： Acylation HY zeolite Catalyst Anisole Acetic anhydride Synthesis Aromatic ketone

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Electrochemical characteristics of amorphous MgTi_xNi(x = 0,0.1,and 0.2) hydrogen storage alloys

引用

Rare Metals 2010年第5期29卷 486-490页

作者： LIU Suqin,ZHAO Wenjuan,HUANG Kelong,and HUANG Hongxia college of chemistry and chemical {3.ing,Central South university,changsha 410083.china college of chemistry and chemical {3.ing Central South University Changsha China

MgTixNi （x = 0, 0.1, and 0.2） alloys were successfully prepared by mechanical alloying （MA）, and the influence of milling time on the electrochemical characteristics of the electrodes was discussed. MgTixNi alloys after 90 h milling displayed the best electrochemical performance The X-ray diffraction patterns showed that the alloy ball-milled for 90 h was amorphous with a widened diffraction peak. The charge-discharge tests indicated that these alloys had good electrochemical activation properties, and the MgTi0.2Ni alloy electrode exhibited the best cycle performance. The initial discharge capacity of the MgTi0.2Ni alloy reached up to 401.1 mAh·g^-1, and the retention rate of capacity was 3..0% after 3. cycles, much higher than that of MgNi （17.3.）. The Tafel polarization curves revealed that Ti addition could enhance the anticorrosion performance of these alloys in alkali solution, which was responsible for the ameliorated cyclic stability of these alloy electrodes.

关键词： hydrogen storage alloys titanium electrochemical properties mechanical alloying

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Drag reduction of flow boiling with polymer additives

引用

Journal of Central South university of Technology 2001年第2期8卷 143-146页

作者： QIU Yun ren 1,CHEN Wei ping 2,SI Qin 3.(1.college of chemistry and chemical {3.ing, Central South university, changsha 410083. china 2.Editorial Office of Journal of Central South university, changsha 410083. china 3.college of chemical E 1. college of chemistry and chemical {3.ing Central South University 410083 Changsha China 2. Editorial Office of Journal of Central South university 410083 Changsha China 3. college of chemical engineering Tianjin University 300072 Tianjin China

The drag reducing effect of polymer additive aqueous solution was investigated in flow boiling, and the polymer additives were two kinds of polyacrylamide (PAM) with relative molecular mass about 2.56×10 6 and 8.55×10 6. The frictional pressure drop was calculated according to the measured total pressure drop. The results show that the flow drag of flow boiling is reduced by adding a small amount of PAM to water when heat flux is in the range of 15.1 kW·m -2 to 47.0 kW·m -2 , when the mass fraction of PAM is higher than 2.0×10 -5 , the drag reducing effect is obvious. Drag reducing effect of PAM, whose relative molecular mass is 8.55×10 6, is slightly better than that of 2.56×10 6 at the same mass fraction, and the greater the flow rate of the additive solution, the better the effect of the drag reduction.

关键词： polymer additive flow boiling drag reduction pressure drop

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：