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Microwave-assisted reaction of peptide formation by amino acid with phosphate:Exploration of the most possible channels for the origin of life

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Science China chemistry 2006年第4期49卷 351-356页

作者： HU Rong1, TIAN Jinping2.& YIN Yingwu2.3 1. college of chemistry & Environment Protection {2., Southwest university for Nationalities, Chengdu 610041, China 2. TH-UNIS Insight Co., Ltd., Beijing 100085, China 3. Key Laboratory of Bioorganic Phosphorus chemistry & chemical Biology, Ministry of Education, Department of chemistry, Tsinghua university, Beijing 100084, China college of chemistry & Environment Protection {2. Southwest University for Nationalities Chengdu China TH-UNIS Insight Co. Ltd. Beijing China Key Laboratory of Bioorganic Phosphorus chemistry & chemical Biology Ministry of Education Department of Chemistry Tsinghua University Beijing China

Microwave-assisted reaction of peptide formation by amino acids with phosphate was studied. The results showed that the products were a mixture of peptides containing dipeptide, oc- tapeptides and cyclic peptides, which could be obtained in a short time. Polyphosphate was also produced synchronously by the intermolecular condensation of phosphate. The polymerization de- gree reached 99% (pyrophosphate 64%, trimetaphosphate 35%) after 2.h at 2.0℃ under microwave irradiation. The intermediates of the mixed anhydrides formed by the intermolecular condensation of phosphates and glycin were determined by ESI-MS. Peptides were also produced by the reaction of amino acids with trimetaphosphate in aqueous solution. The conversion degree of valine reached 46.5% even at room temperature. The cyclic process of peptide formation and phosphate polymeri- zation, regeneration and utilization in amino acids-phosphate system under microwave irradiation was detected and proved. Peptides could be continually formed only by inputting energy into this system. The above recycle may be the most possible process for primitive peptide formation in the origin of life.

关键词： microwave, phosphate, amino acid, peptide, origin of life.

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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. engineering, hunan university, Changsha 410082. China State Key Laboratory for Chemo/Biosensing and Chemometrics college of chemistry and {2. engineering 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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Study on the properties of polyaniline for med in KOH solution

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西南师范大学学报(自然科学版) 1999年第5期24卷 562-565页

作者： Li Nianbing 1,Zhang Shengtao 2.Ding Peidao 3 1 college of chemistry and {2. engineering,Southwest China Normal university,Chongqing 400715 2.college of chemistry and {2. engineering,Chongqing university,Chongqing 400044 3 college of Materi 西南师范大学重庆重庆大学重庆

Electropolymerization of aniline in KOH solution and properties of the polymer were studied by in situ reflex ellipsometry, cyclic voltammetry and fluorescence spectroscopic method. The process of electropolymerization of aniline was different in alkaline and in acidic aqueous media. The complex refractive indices and the fluorescence spectra indicated that the polyaniline was a sort of luminous material.

关键词： polyaniline electropolymerization alkaline solution ellipsometry fluorescence luminous material

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Applying flexible molecular docking to simulate protein retention behavior in hydrophobic interaction chromatography

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Science China chemistry 2007年第5期50卷 675-682页

作者： ZHOU Peng1, TIAN FeiFei1 & LI ZhiLiang1,2.1 college of chemistry and {2. engineering, Chongqing university, Chongqing 400044, China 2.State Key Laboratory of Chemo/Biosensing and Chemometrics, Changsha 410082. China college of chemistry and {2. engineering Chongqing University Chongqing China State Key Laboratory of Chemo/Biosensing and Chemometrics Changsha China

Interaction between proteins and stationary phase in hydrophobic interaction chromatography (HIC) is differentiated into two thermodynamic processes involving direct nonbonding/conformation interac- tion and surface hydrophobic effect of proteins, hence quantitatively giving rise to a binary linear rela- tion between HIC retention time (RT) at concentrated salting liquid and ligand-protein binding free en- ergy. Then, possible binding manners for 2. proteins of known crystal structures with hydrophobic ligands are simulated and analyzed via ICM flexible molecular docking and genetic algorithm, with re- sults greatly consistent with experimental values. By investigation, it is confirmed local hydrophobic effects of proteins and nonbinding/conformation interaction between ligand and protein both notably influence HIC chromatogram retention behaviors, mainly focusing on exposed portions on the protein surface.

关键词： hydrophobic interaction chromatography, flexible molecular docking, genetic algorithm, protein, salting-in factor

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Study of technology on MnSO4 preparation from highferrous manganese spar

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西南师范大学学报(自然科学版) 1999年第5期 566-570页

作者： Hu Debin 1,Li Nianbing 2. Zhang Shengtao 1, Han Lianyi 1 1 college of chemistry and {2. engineering,Chongqing university,400044 2.college of chemistry and {2. engineering,Southwest China Normal university,400715

Preparation of MnSO 4 from high ferrous manganese spar is studied by *** in traditional ways,such as undesirable increasing of solution viscosity and difficulty in neutralization, are solved *** recovery ratio can be ... 详细信息

关键词： high ferrous manganese spar manganese recovery ratio filtration time

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

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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 {2. engineering,Central South university,Changsha 410083,China college of chemistry and {2. engineering 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 MgTi0.2.i alloy electrode exhibited the best cycle performance. The initial discharge capacity of the MgTi0.2.i alloy reached up to 401.1 mAh·g^-1, and the retention rate of capacity was 31.0% after 30 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

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Characterization and Electrochemical Properties of LiMn_2._4 Thin Films Prepared by Solution Deposition

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Journal of Wuhan university of Technology(Materials Science) 2006年第3期21卷 54-56页

作者：吴显明 college of chemistry and {2. engineering Jishou UniversityJishou 416000China

LiMn2.4 thin films were prepared by solution deposition using lithium acetate and manganese acetate us raw materials. The phase constitution and surface morphalogy were observed by X-ray diffraction and scanning electron microscopy. The electrochemical properties of the thin films were studied by cycilc voltammetry, charge- discharge experiments and impedance spectroscopy in 1 mol· L^-1 LiPF6 / EC- DMC solution using lithium metal as both the counter and reference electrodes. The films prepared by this method are of spinel phase. The lattice parameter increases with the annealing temperature aud annealing time. The film annealed at 750 ℃ for 30 minutes has the highest capacity of 34.5 μAh ·cm^- 2.μm^-1 , and its capacity loss per cycle is 0. 05% afrer being cycled 100 times.

关键词： thin films lithium manganese oxide lithium-ion battery solution deposition

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Synthesis of nano onion-like fullerenes by using Fe/Al_2._3 as catalyst by chemical vapor deposition

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Chinese Science Bulletin 2009年第1期54卷 137-141页

作者： LIU XuGuang1,2.WANG CunJing1,2.YANG YongZhen1,3,GUO XingMei1,2.WEN HaiRong1,2.& XU BingShe1,3 1 Key Laboratory of Interface Science and engineering in Advanced Materials,Ministry of Education,Taiyuan university of Tech-nology,Taiyuan 03002.,China 2.{2. of chemistry and chemical engineering,Taiyuan university of Technology,Taiyuan 03002.,China 3 {2. of Materials Science and engineering,Taiyuan university of Technology,Taiyuan 03002.,China Key Laboratory of Interface Science and engineering in Advanced Materials Ministry of Education Taiyuan University of Technology Taiyuan 030024 China college of chemistry and {2. engineering Taiyuan University of Technology Taiyuan 030024 China college of Materials Science and engineering Taiyuan University of Technology Taiyuan 030024 China

Nano-carbon materials were synthesized by the catalytic decomposition of acetylene at 400℃ by using Fe/Al2.3 as catalyst. The product was refluxed in 36% concentrated HCl at 60℃ for 48 h in order to re-move the catalyst support. The samples were examined by scanning and high resolution transmission electron microscopy,energy dispersive spectroscopy and X-ray diffraction. The results show that nano onion-like fullerenes encapsulating a Fe3C core were obtained. These had a structure of stacked graphitic fragments,with diameters ranging from 15―50 nm. When the product was further heat-treated at 1100℃ for 2.h,nano onion-like fullerenes with a clear concentric graphitic layer structure were obtained. The growth mechanism of nano onion-like fullerenes encapsulating metal cores is suggested to follow a vapor-solid growth model.

关键词：纳米碳材料化学蒸发沉积作用合成增长机制

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Electrochemical synthesis of ammonia using a cell with a Nafion membrane and SmFe_(0.7)Cu_(0.3-x)Ni_xO_3(x=0―0.3) cathode at atmospheric pressure and lower temperature

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Science China chemistry 2009年第8期52卷 1171-1175页

作者： XU GaoChao,LIU RuiQuan & WANG Jin college of chemistry and {2. engineering,Xinjiang university,Urumqi 830046,China college of chemistry and {2. engineering Xinjiang University Urumqi China

Samaria-doped ceria Ce0.8Sm0.2.2.δ(SDC) and SmFe0.7Cu0.3-xNixO3 have been synthesized by the sol-gel method and characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM) and scanning electron microscopy(SEM).The electrochemical synthesis of ammonia was investigated at atmospheric pressure and low temperature,using the SFCN materials as the cathode,a Nafion membrane as the electrolyte,nickel-doped SDC(Ni-SDC) as the anode and silver-platinum paste as the current *** was synthesized from 2. to 100℃ when the SFCN materials were used as cathode,with SmFe0.7Cu0.1Ni0.2.3 giving the highest rates of ammonia *** maximum rate of evolution of ammonia was 1.13 × 10-8 mol·cm-2.s-1 at 80℃,and the current efficiency reached as high as 90.4%.

关键词： electrochemical synthesis of ammonia ammonia synthesis at atmospheric pressure and low temperature Nafion membrane metal oxide

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An efficient chiral synthesis of (R)-N-[3-acetyl-4-(2.hydroxy-3-isopropylamino-propoxy)phenyl]-butanamide with high enantioselectivity

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Science China chemistry 2009年第8期52卷 1216-1219页

作者： WANG NaiXing1,2.& TANG XinLiang1,3 1 Technical Institute of Physics and chemistry,Chinese Academy of Sciences,Beijing 100080,China 2.college of chemistry and chemical engineering,Graduate university of Chinese Academy of Sciences,Beijing 100049,China 3 School of chemical engineering and Environment,Beijing Institute of Technology,Beijing 100081,China Technical Institute of Physics and chemistry Chinese Academy of Sciences Beijing China college of chemistry and {2. engineering Graduate University of Chinese Academy of Sciences Beijing China School of chemical engineering and Environment Beijing Institute of Technology Beijing China

R-Enantiomer of the β-receptor antagonist N-[3-acetyl-4-(2.hydroxy-3-isopropylamino-propoxy)phenyl] butanamide with high enantioselectivity was synthesized from cheap starting materials and enantiopure chiral reagent through an efficient,convenient and practical synthetic *** product was detected by 1H NMR,13C NMR,and MS,and the enatiomeric excess was determined by chiral HPLC analysis using a chiracel AD-H column.

关键词： chiral synthesis enantioselectivity enatiomeric excess chiral HPLC analysis

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