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Status of study on biological and toxicological effects of nanoscale materials

Science china chemistry 2005年第5期48卷 385-394页

作者： WANG Bing1, FENG Weiyue1, ZHAO Yuliang1, XING Gengmei1, CHAI Zhifang1, WANG Haifang2.& JIA Guang3.1. Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials (Nanosafety Lab), Institute of High Energy Physics, Chi-nese Academy of Sciences, Beijing 100049, china 2. {2. of chemistry and Molecular {3.ing, Peking university, Beijing 100871, china 3. Department of Occupational and Environmental Health Sciences, School of Public Health, Peking university, Beijing 100083. china Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials (Nanosafety Lab) Institute of High Energy Physics Chinese Academy of Sciences Beijing China college of chemistry and Molecular {2.ing Peking University Beijing China Department of Occupational and Environmental Health Sciences School of Public Health Peking University Beijing China

Because the physical and chemical properties of nanosized materials mostly differ from the existing microsized materials, their potential impacts on human health and the envi-ronment will be topics under the serious discussions in press and in a number of international scientific journals. We analyze and summarize the existing data of the experimental study on the biological activities and adverse effects of nanoscale materials/particles including single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron powders. Though some biological behaviors of nanoscale materials observed cannot be understood on the basis of the current knowledge, as the existing data are mostly preliminary, it is too early to make some ex-clusive conclusions on biological activities (or the toxicity) of any of nanoscale materials. The experimental techniques, the current topics, and the future research directions for this new re-search field are also discussed.

关键词： nanomaterials, single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron, biological activity and toxicological effect.

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Supporting of Nickel(Ⅱ) Acenaphthenediimine with Free Amino Group for Ethylene Polymerization

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Journal of Wuhan university of Technology(Materials Science) 2010年第2期25卷 260-264页

作者：胡扬剑 Department of chemistry and chemical {2.ing Huaihua College

Bis （4-（4-amino-3. 5-diethylbenzyl）-2. 6-diethylphenylimino） acenaphthene] di- chloronickel （NiLCl2. was prepared and supported on SiO2.modified by methyl trichlorsilane（S-1） and on SiO2.MgCl2.TiCl4 （S-2. respectively. Two supported catalysts S-1 and S-2.used as catalysts for ethylene polymerization were studied and the influences of various polymerization conditions, including the polymerization temperature, cocatalysts, Al/Ni molar ratio on the catalytic activity, branching degree and branch length of PE were also investigated. The experimental results show that the supported catalysts exhibit higher catalytic activity for ethylene polymerization, the highest catalytic activity of S-1 using AlEt2.l as cocatalyst at 50 ℃, reaching 5.8×10^5gPE/molNi·h, and needed lower Al/Ni molar ratio compared to homogeneous analogue.

关键词： nickel diimine complex supported catalyst branched polyethylene diethylaluminium chloride

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A NOVEL INTERPRETATION OF CONCENTRATION DEPENDENCE OF VISCOSITY OF DILUTE POLYMER SOLUTION

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Chinese Journal of Polymer Science 2000年第1期18卷 57-67页

作者： Yan Pan Rong-shi Cheng college of Material Science and engineering, South{2. {3. of Technology, Guangzhou 510641,{2. college of chemistry and chemical engineering, Nanjing {3., Nanjing 2.0093.{2. 华南理工大学广东广州

The concentration dependence of the reduced viscosity of dilute polymer solution is interpreted in the light of a new concept of the self-association of polymer chains in dilute solution. The apparent self-association constant is defined as the molar association constant divided by the molar mass of individual polymer chain and is numerically interconvertible with the Huggins coefficient. The molar association constant is directly proportional to the effective hydrodynamic volume of the polymer chain in solution and is irrespective of the chain architecture. The effective hydrodynamic volume accounts for the non-spherical conformation of a short polymer chain in solution and is a product of a shape factor and hydrodynamic volume. The observed enhancement of Huggins coefficient for short chain and branched polymer is satisfactorily interpreted by the concept of self-association. The concept of self-association allows us to predict the existence of a boundary concentration C-s(dynamic contact concentration) which divides the dilute polymer solution into two regions.

关键词： self-association polymer solution viscosity concentration dependence

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Colloidal organic carbon in Huanghe, changjiang and Qiantang River

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Chinese Science Bulletin 1998年第11期43卷 915-917页

作者： WANG Jiangtao college of chemistry and {2. {3.ing, Ocean university of Qingdao, Qingdao 2.6003. china Callege of chemistry and chemical {2.ing Ocean University of Qingdao Qingdao China

Cross-flow ultrafiltration techniques have been used to separate colloidal organic carbon (COC) from natural water, and COC in three water samples that were collected from Huanghe, changjiang and Qiantang River was determined. On average, COC comprised about 68.6% of the total dissolved organic carbon. The abundance of COC suggested that COC could play important roles in input fluxes and biogeochemistry of organic carbon.

关键词： cross-flow ultrafiltration colloidal organic carbon.

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Crystal structure of a novel two-dimensional supramolecular network based on polyoxoanion and yttrium~Ⅲcoordination cation

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Science china chemistry 2005年第z1期48卷 9-13页

作者： HE Shuiyang,PENG Ke,NING Wei,WANG Daqi & SHI Qizhen Department of chemistry,Northwest university and Shaanxi Key Laboratory of Physico-Inorganic chemistry,Xi’an 710069,{3. college of chemistry and chemical engineering,Liaocheng university,Liaocheng 2.2.59,{3. Department of chemistry Northwest University and Shaanxi Key Laboratory of Physico-Inorganic Chemistry Xi’an China college of chemistry and {2. {3.ing Liaocheng University Liaocheng China

A novel compound (NH4)2.(H2.)8[PMo10V2.40]·10H2. has been prepared in an aqueous solution and characterized by elemental analysis, IR, and TG-DTG analysis. X-ray diffraction analysis was carried out on (NH4)2.(H2.)8 [PMo10V2.40]·10H2. single crystal, which crystallizes in the monoclinic system of a space group P2./C with a=0.9871(3. nm,b=1.542.(5) nm,c=2.792.(9) nm,β=94.183.5)°and Z=2. In the compound, a two-dimensional network is constructed by the PMo10V2.405- anion and the Y(H2.)83. cation building blocks via hydrogen bonding exhibiting the porous structure.

关键词： crystal structure, polyoxoanion, yttrium, supramolecular network.

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DFT Calculation of Room Temperature Ionic Liquid 1-Ethyl-3.Methyl-Imidazolium Chlorocuprate (Ⅰ)

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china Petroleum Processing & Petrochemical Technology 2008年第1期10卷 55-62页

作者： Lü Renqing Cao Zuogang (college of chemistry and {2. {3.ing, china university of Petroleum (East china), Dongying 2.7061) college of chemistry and {2. {3.ing China University of Petroleum (East China) Dongying 257061 China

The density functional theory （DFT） has been employed to investigate the electronic structures ofEMIM^＋（1-ethyl-3.methylimidazolium＋）, CuCl2.-, Cu2.l3.- and EMIM^＋-CuCl2.-, EMIM^＋-Cu2.l3.- pairs. Full optimization and frequency analyses of EMIM^＋, CuCl2.-, Cu2.l3.-, eight initial EMIM^＋-CuCl2.-, and six initial EMIM^＋-Cu2.l3.- geometries have been carried out using Gaussian-94 software-package at 6-3.I＋G （d, p） basis set level for hydrogen, carbon, nitrogen, chlorine atoms and the Hay-Wadt effective core potential for copper atoms. The electronic structures of the lowest energy of EMIM^＋-CuCl2.-, EMIM^＋-Cu2.l3.- pairs, single EMIM^＋, CuCl2.-, and Cu2.l3.- have been comparatively studied. The calculated results showed that the optimized EMIM^＋-CuCl2.- pair conformer of the lowest energy was five ring moiety parallel to CuCl2.- plane with a distance of around 3.5,A, while EMIM^＋-Cu2.l3.- pair conformer of the lowest energy was five ring moiety of EMIM^＋ perpendicular to Cu2.l3.- plane with a distance of around 3.0 ,A between terminal chlorine atoms and 5-ring plane of EMIM^＋. The cohesion between cation and anion is electrostatic interaction and C-H---Cl hydrogen bonds are reinforced by charge assistance. The frequency analyses suggested that all stationary points are minimum points because of absence of imaginary frequency. The low energy of interaction caused by bulky asymmetry of EMIM^＋, and charge dispersion of cation and anion give rise to low melting point of ionic liquids EMIM^＋-CuCl2.-, and EMIM^＋-Cu2.l3.- . The interaction energy caused by the distance between cations and anions was investigated by single point energy scan.

关键词： ionic liquid density functional theory 1-ethyl-3.methylimidazolium chlorocuprate (I)

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Study on Laboratory Method for Refining of SR Diesel Fuel

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china Petroleum Processing & Petrochemical Technology 2006年第3期8卷 57-60页

作者： Li Junling1 Zheng Tinglu2.Han Zhaping3.(1. college of {2. and chemical {3.ing, china Petroleum university (East china) Dongying 2.7061 2. Shandong Jingbo Petrochemical Co. 3. Shandong Donghai Petrochemical Co.) college of chemistry and {2. {3.ing China Petroleum University (East China) Dongying 257061 China Shandong Jingbo Petrochemical Co. China Shandong Donghai Petrochemical Co. China

The method for refining the straight-run diesel fuel was studied in laboratory scale in order to make the acid number of diesel fraction comply with the standard while removing the naphthenic acids contained in diesel without causing environmental pollution. After comparing the effect of refining using three solvents, the isopropyl alcohol-HOA was specified as the best solvent. Meanwhile, the relationship between the acid number of diesel fraction and the amount of solvent used and the relationship between the concentration of solvent and temperature and the stability of diesel in terms of its acid number were also investigated. Experimental results had shown that when the mass fraction of the HOA-IPA solvent was 2.% at a dosage of 17 mL of the solvent and a temperature of 3.℃, the acid number of the refined diesel fraction was 0.015 mg KOH/g with a good stability of acidity in the diesel fraction.

关键词： straight-run diesel deacidification refining naphthenic acid

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changes of decay rates of radioactive ^(111)In and ^(3.)P induced by mechanic motion

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Science china chemistry 2007年第2期50卷 170-174页

作者： HE YuJian1,QI Fei2.& QI ShengChu3.1 college of {2. and chemical {3.ing,Graduate university of Chinese Academy of Sciences,Beijing 100049,china 2.No. 1,Gravenhurst Court,Gaithersburg,Md 2.878,USA 3.Department of Applied {2.,Peking university,Beijing 100871,china college of chemistry and {2. {3.ing Graduate University of Chinese Academy of Sciences Beijing China No. 1 Gravenhurst Court Gaithersburg USA Department of Applied chemistry Peking University Beijing China

The changes of decay rates of radionuclide 111In(electron capture) and 3.P(β decay) induced by exter-nal mechanic motion are studied. The results indicate that,in the external circular rotation in clockwise and anticlockwise centrifuge on Northern Hemisphere(radius 8 cm,2.00 r/min) ,the half life of 111In compared with the referred(2.83.d) is decreased at 2.83. and increased at 1.77%,respectively;the half life of 3.P compared with the referred(14.2. d) is decreased at 3.78% and increased at 1.75%,respec-tively. When the clockwise and anticlockwise rotations increase to 4000 r/min,the half life of 111In is decreased at 11.3.% and increased at 6.3.%,respectively;the half life of 3.P is decreased at 10.08% and increased at 4.3.%,respectively. When the circular rotation is removed,the decay rates of 111In and 3.P return back to the referred,respectively. It is found that the external circular rotations in clockwise and anticlockwise centrifuge selectively increased and decreased the decay rates of 111In and 3.P,respec-tively,and the effects are strongly dependent on the strength of circular rotation. It is suggested that these effects may be caused by the chiral interaction.

关键词： circular rotation helical motion 111In 3.P decay rate chirality

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Synthesis,characterization,properties and crystal structure of heterometallic 1D coordination polymers {[CuLZn·CuLZn(H_2.)]·H_2.}_n

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Science china chemistry 2006年第4期49卷 338-344页

作者： TAO Ruojie1, LI Fu’an1, ZANG Shuangquan1, CHENG Yanxiang2.& NIU Jingyang1 1. chemistry and chemical {2.ing {3. of Henan university, Kaifeng 475001, china 2. changchun Institute of Applied chemistry, Chinese Academy of Sciences, changchun 13.02., china chemistry and chemical {2.ing {3. of Henan university Kaifeng China changchun Institute of Applied chemistry Chinese Academy of Sciences Changchun China

Copper-zinc heterometallic 1D chain coordination polymer has been synthesized and characterized by elemental analysis, and IR spectra etc. The crystal structure was determined by single-crystal X-ray diffraction analyses. The title complex is 1D chain coordination polymer with the chemical formula {[CuLZn·CuLZn(H2.)]·H2.}n, where H4L=N-(2.hydroxybenzamido)-N’-(3.carboxy- lsalicylidene)ethylenediamine. Its structural unit is comprosed of two tetranuclear cycles formed by two dissymmetrical tetranuclear units. These units polymerized each other to form 1D chain coordi- nation polymer.

关键词： copper, zinc, heterometallic coordination polymer, crystal structure.

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

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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 {2. {3.ing, hunan university, changsha 4.0082, china State Key Laboratory for Chemo/Biosensing and Chemometrics college of chemistry and {2. {3.ing Hunan University Changsha 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

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