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Soft chemical synthesis and electrochemical properties of tin oxide-based materials as anodes for lithium ion batteries 被引量:1
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作者 何则强 李新海 +4 位作者 熊利芝 吴显明 刘恩辉 侯朝辉 邓凌峰 《Journal of Central South University of Technology》 2004年第2期142-146,共5页
A novel soft chemical approach was developed to synthesize tin oxide-based powders. The microstructure, morphology, and electrochemical performance of the materials were investigated by X-ray diffraction, scanning ele... A novel soft chemical approach was developed to synthesize tin oxide-based powders. The microstructure, morphology, and electrochemical performance of the materials were investigated by X-ray diffraction, scanning electron microscope and electrochemical methods. The results show that the particles of tin oxide-based materials form an interconnected network structure like mesoporous material. The average size of the particles is about 200 nm. The materials deliver a charge capacity of more than 570 mA·h·g-1. And the capacity loss per cycle is about 0.15% after being cycled for 30 times. The good electrochemical performance indicates that tin oxide-based materials are promising anodes for lithium ion batteries. 展开更多
关键词 lithium ion battery tin oxide ANODE soft chemical synthesis electrochemical property
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Soft chemical synthesis and luminescence properties of red long-lasting phosphors Y_2O_2S:Sm^(3+)
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作者 Yan-juan Li Ming-wen Wang +2 位作者 Lu-dan Zhang Duo Gao Shi-xiang Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2013年第10期972-977,共6页
Sm3+-activated Y2028 red phosphors were prepared by the combustion method and microemulsion method at the first time. X-ray characterization and electron diffraction show that, Y202S:Sm3+, Ti4+, Mg2+ samples prep... Sm3+-activated Y2028 red phosphors were prepared by the combustion method and microemulsion method at the first time. X-ray characterization and electron diffraction show that, Y202S:Sm3+, Ti4+, Mg2+ samples prepared by these two methods are pure hexagonal crystals in structure with a trivial change due to dopants. Scanning electron microscopy (SEM) results show that the product presents an almond-like sheet in uniform size. Under the excitation of 269 nm ultraviolet light, Y202S:Sm3+ samples fabricated by these two methods exhibit three main groups of red emission lines located at 564, 604, and 656 nm, respectively, which are attributed to the transitions of 4G5/2 →6H5/2, 4G~/2 →6H7/2, 4G5/2 →6H9/2, respectively. The samples prepared by microemulsion are seven times higher in fluorescent emission intensity and half time longer in afterglow time than that prepared by combustion. 展开更多
关键词 PHOSPHORS soft chemical synthesis LUMINESCENCE combustion MICROEMULSION
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A FACILE CHEMICAL SYNTHESIS of PENTADEOXYRIBONUCLEOTIDE d-TGGGT via PHOSPHOTRIESTER METHOD
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作者 Dao Yuan DING Wen Xia TANG Coordination Chemistry Institute,Nanjing University,Nanjing 210008 Chun Guang WANG Li He ZHANG National Laboratory of Natural and Biomimetic Drugs,Beijing Medical University,Beijing 100083 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第9期693-696,共4页
In this paper,we report the chemical synthesis of oligonucleotide d-TGGGT using phosphotriester method.The protected pentamer d-MmtTGibGibGibT(=p-ClC6H_4-O(O)P)was deblocked by treatment with concentrated ammonium hyd... In this paper,we report the chemical synthesis of oligonucleotide d-TGGGT using phosphotriester method.The protected pentamer d-MmtTGibGibGibT(=p-ClC6H_4-O(O)P)was deblocked by treatment with concentrated ammonium hydroxide and 80% acetic acid.The pure d-TGGGT obtained by chromatorgraphy on DEAE-Sephadex A-25 and Q-Sepharose FF could be hydrolyzed completely and confirmed by base ratio. 展开更多
关键词 GENE In A FACILE chemical synthesis of PENTADEOXYRIBONUCLEOTIDE d-TGGGT via PHOSPHOTRIESTER METHOD DAI
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Preparation and characterization of calcium aluminate by chemical synthesis 被引量:1
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作者 Feng Chen Yanruo Hong +1 位作者 Jialin Sun Jinglong Bu 《Journal of University of Science and Technology Beijing》 CSCD 2006年第1期82-86,共5页
Saturated Ca(OH)2 and AlCl3 solutions were used to synthesize calcium aluminate hydrate precipitates at room temperature; high purity calcium aluminate powders with stable phases were made by calcination of the prec... Saturated Ca(OH)2 and AlCl3 solutions were used to synthesize calcium aluminate hydrate precipitates at room temperature; high purity calcium aluminate powders with stable phases were made by calcination of the precursors at a temperature as low as 1100℃. PSD and BET analysis revealed the particles with sizes ranging from submicrometer to several micrometers and with a specific area of 13 m^2/g. The measurement of hydraulic exotherm revealed that the exothennal rate is in peak for about 2 h. The exothermal quantities are 449.24 J/g at 12 h and 488.38 J/g at 24 h. Its strength development is quick and the 1 day curing strength is almost equal to 100% of the 3 days curing strength in the mortar test. 展开更多
关键词 calcium aluminate PREPARATION CHARACTERIZATION chemical synthesis
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Progress in Chemical Synthesis of Peptides and Proteins
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作者 Wen Hou Xiaohong Zhang Chuan-Fa Liu 《Transactions of Tianjin University》 EI CAS 2017年第5期401-419,共19页
For the proteins that cannot be expressed exactly by cell expression technology (e.g., proteins with multiple posttranslational modifications or toxic proteins), chemical synthesis is an important substitute. Given th... For the proteins that cannot be expressed exactly by cell expression technology (e.g., proteins with multiple posttranslational modifications or toxic proteins), chemical synthesis is an important substitute. Given the limited peptide length offered by solid-phase peptide synthesis invented by Professor Merrifield, peptide ligation plays a key role in long peptide or protein synthesis by ligating two small peptides to a long one. Moreover, high-molecular-weight proteins must be synthesized using two or more peptide ligation steps, and sequential peptide ligation is such an efficient way. In this paper, we reviewed the development of chemical protein synthesis, including solid-phase peptide synthesis, chemical ligation, and sequential chemical ligation. © 2017, The Author(s). 展开更多
关键词 chemical modification PEPTIDES PROTEINS Surgical equipment synthesis (chemical)
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Major Chemical Synthesis Methods and Application Progress of Sex Pheromone of Asian Corn Borer
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作者 Jiang Zhongping Li Jintao +3 位作者 Wang Yingxiu Zhang Zuoshan Liu Qinsheng Wang Xia 《Plant Diseases and Pests》 CAS 2020年第1期17-21,共5页
This article reviews the main chemical synthesis methods of sex pheromone of Asian corn borer, common strategies for constructing dou-ble bond, molecular composition and field application progress of sex pheromone of ... This article reviews the main chemical synthesis methods of sex pheromone of Asian corn borer, common strategies for constructing dou-ble bond, molecular composition and field application progress of sex pheromone of Asian corn borer, which will provide reference for biological control of Asian corn borer. 展开更多
关键词 ASIAN CORN BORER SEX PHEROMONE chemical synthesis Application
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Simple chemical synthesis and isotropic negative thermal expansion in MHfF_(6)(M=Ca,Mn,Fe,and Co) 被引量:1
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作者 Yongqiang Qiao Sen Zhang +6 位作者 Peixian Zhang Juan Guo Andrea Sanson Xi Zhen Kaiyue Zhao Qilong Gao Jun Chen 《Nano Research》 SCIE EI CSCD 2024年第3期2195-2203,共9页
The rapid progress of modern technologies has accelerated the prominence of thermal expansion mismatch between materials,and tunable thermal expansion materials will be a powerful safeguard against this challenge.Here... The rapid progress of modern technologies has accelerated the prominence of thermal expansion mismatch between materials,and tunable thermal expansion materials will be a powerful safeguard against this challenge.Here,isotropic MHfF_(6)(M=Ca,Mn,Fe,and Co)compounds with tunable thermal expansion have been produced via a low-cost synthetic method and investigated.By utilizing temperature dependent X-ray diffraction(XRD)and Raman spectroscopy,combined with first principles calculations,it was revealed that the transverse thermal vibrations of the F atoms are dominated by low-frequency phonons with negative Grüneisen parameters and are therefore the origin of the negative thermal expansion(NTE).Very interestingly,with the increase of the M atomic number,the metal…F atomic linkages become stiffer,reducing the number of vibrational modes with negative Grüneisen parameters,so that the strong NTE can be gradually adjusted to moderate NTE and to near zero thermal expansion.The present study achieves the tunable thermal expansion in a new compound family and shed light on the internal mechanism from the perspective of lattice vibrational dynamics. 展开更多
关键词 negative thermal expansion fluorides chemical synthesis nanosheet structure first principles calculations
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Efficient Chemical Synthesis and Folding of Mirror-Image Tropomyosin Receptor Kinase A Using the Strategy of Removable Glycosylation Modification
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作者 Tongyue Wang Weiwei Shi +1 位作者 Guo-Chao Chu Yi-Ming Li 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2024年第19期2316-2322,共7页
Comprehensive Summary The strategy of removable glycosylation modification was used to overcome the low-efficiency problem encountered in the chemical synthesis of the mirror-image D-version of the immunoglobulin(Ig)-... Comprehensive Summary The strategy of removable glycosylation modification was used to overcome the low-efficiency problem encountered in the chemical synthesis of the mirror-image D-version of the immunoglobulin(Ig)-like domain of tropomyosin receptor kinase A(DlgCTrkA),a protein molecule needed for mirror-image screening of D-peptide ligands targeting this cell membrane receptor.It was found that O-linked-β-N-acetyl-D-glucosamine(O-GlcNAc)modification at^(D)Ser^(312),or^(D)Ser^(320)can significantly improve the efficiency of DlgCTrkA synthesis and folding,while O-GlcNAc modification at^(D)Ser^(330)showed barely any improvement.This study provides a new example demonstrating the power of the removable glycosylation modification strategy in the chemical synthesis and folding of difficult-to-obtain proteins.It also presents evidence that removable glycosylation modification at different sites would significantly affect the efficiency of protein folding promoted by this strategy. 展开更多
关键词 chemical protein synthesis Removable glycosylation modification Synthetic methods Protein folding D-protein
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Study on trifluoromethanesulfonic acid-promoted synthesis of daidzein: Process optimization and reaction mechanism
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作者 Hai Cao Haibin Yang +3 位作者 Yanxiong Fang Yuandi Zeng Xiaolan Cai Jingjing Ma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第7期132-139,共8页
Daidzein has been widely used in pharmaceuticals,nutraceuticals,cosmetics,feed additives,etc.Its preparation process and related reaction mechanism need to be further investigated.A cost-effective process for synthesi... Daidzein has been widely used in pharmaceuticals,nutraceuticals,cosmetics,feed additives,etc.Its preparation process and related reaction mechanism need to be further investigated.A cost-effective process for synthesizing daidzein was developed in this work.In this article,a two-step synthesis of daidzein(Friedel–Crafts acylation and[5+1]cyclization)was developed via the employment of trifluoromethanesulfonic acid(TfOH)as an effective promoting reagent.The effect of reaction conditions such as solvent,the amount of TfOH,reaction temperature,and reactant ratio on the conversion rate and the yield of the reaction,respectively,was systematically investigated,and daidzein was obtained in 74.0%isolated yield under optimal conditions.Due to the facilitating effect of TfOH,the Friedel–Crafts acylation was completed within 10 min at 90℃ and the[5+1]cyclization was completed within 180 min at 25℃.In addition,a possible reaction mechanism for this process was proposed.The results of the study may provide useful guidance for industrial production of daidzein on a large scale. 展开更多
关键词 synthesis Optimal design chemical processes Reaction mechanism
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Natural forests exhibit higher organic carbon concentrations and recalcitrant carbon proportions in soil than plantations:a global data synthesis
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作者 Xiuqing Nie Hui Wang +1 位作者 Jian Wang Shirong Liu 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第5期131-141,共11页
Different chemical compositions of soil organic carbon(SOC)affect its persistence and whether it signifi-cantly differs between natural forests and plantations remains unclear.By synthesizing 234 observations of SOC c... Different chemical compositions of soil organic carbon(SOC)affect its persistence and whether it signifi-cantly differs between natural forests and plantations remains unclear.By synthesizing 234 observations of SOC chemical compositions,we evaluated global patterns of concentra-tion,individual chemical composition(alkyl C,O-alkyl C,aromatic C,and carbonyl C),and their distribution even-ness.Our results indicate a notably higher SOC,a markedly larger proportion of recalcitrant alkyl C,and lower easily decomposed carbonyl C proportion in natural forests.How-ever,SOC chemical compositions were appreciably more evenly distributed in plantations.Based on the assumed con-ceptual index of SOC chemical composition evenness,we deduced that,compared to natural forests,plantations may have higher possible resistance to SOC decomposition under disturbances.In tropical regions,SOC levels,recalcitrant SOC chemical composition,and their distributed evenness were significantly higher in natural forests,indicating that SOC has higher chemical stability and possible resistance to decomposition.Climate factors had minor effects on alkyl C in forests globally,while they notably affected SOC chemi-cal composition in tropical forests.This could contribute to the differences in chemical compositions and their distrib-uted evenness between plantations and natural stands. 展开更多
关键词 Global data synthesis Natural forest Plantations Soil organic carbon Soil organic carbon chemical composition
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Research Progress on Synthesis of Superoxide Dismutase Mimics
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作者 Delong Bao Xiao Han Anhe Jia 《Expert Review of Chinese Chemical》 2024年第2期15-22,共8页
Research on the synthesis of superoxide dismutase mimics by chemical and biologi-cal synthetic methods were reviewed.The advantages and limitations were analyzed.A prospect for the future development of superoxide dis... Research on the synthesis of superoxide dismutase mimics by chemical and biologi-cal synthetic methods were reviewed.The advantages and limitations were analyzed.A prospect for the future development of superoxide dismutase mimics is proposed. 展开更多
关键词 superoxide dismutase chemical synthesis biological synthesis REVIEW
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Racemic X-ray structure of L-type calcium channel antagonist Calciseptine prepared by total chemical synthesis 被引量:3
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作者 Chen-Chen Chen Shuai Gao +3 位作者 Hua-Song Ai Qian Qu Chang-Lin Tian Yi-Ming Li 《Science China Chemistry》 SCIE EI CAS CSCD 2018年第6期702-707,共6页
Snake toxin Calciseptine as a natural antagonist of L-type calcium channel has potential drug values, but its structural information remains unknown. Here, we report the total chemical synthesis of Calciseptine by usi... Snake toxin Calciseptine as a natural antagonist of L-type calcium channel has potential drug values, but its structural information remains unknown. Here, we report the total chemical synthesis of Calciseptine by using hydrazide based native chemical ligation. The crystal structure of Calciseptine was determined by racemic protein crystallography technique. Compared to the structure of its homologous family protein, we found that Calciseptine is adopting a typical three-finger structure. 展开更多
关键词 protein chemical synthesis calciseptine hydrazide based native chemical ligation racemic protein crystallography
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Thermodynamics for chemical vapor synthesis of Nb nanopowder in NbCl_5-H_2-Ar system
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作者 朱骏 黄凯 +1 位作者 侯军刚 朱鸿民 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第12期3987-3993,共7页
Thermodynamics for chemical vapor synthesis (CVS) of Nb nanopowder in NbCl5-H2-Ar system was investigated by using FactSage software. The validation experiments were conducted to confirm the thermodynamics points. T... Thermodynamics for chemical vapor synthesis (CVS) of Nb nanopowder in NbCl5-H2-Ar system was investigated by using FactSage software. The validation experiments were conducted to confirm the thermodynamics points. The results indicate that under the atmospheric pressure, the reduction approach from NbCl5(g) to Nb(s) is a stage-wise process with the formation of complex sub-chlorides, and is controllable at low hydrogen ratio (mole ratio of n(NbCl5):n(H2)&lt;1:180) and low temperature (&lt;1050 &#176;C). Furthermore, a reasonable amount of inert loading gas is favorable to increase the reduction ratio of NbCl5 and the powder yield. The as-synthesized Nb nanopowder with the homogeneous size of 30-50 nm and the powder yield of 85% (mass fraction) is obtained by the CVS process under n(NbCl5):n(H2):n(Ar)=1:120:1 and 950 &#176;C with the NbCl5 reduction rate of 96.1%. 展开更多
关键词 NbCl5-H2-Ar system chemical vapor synthesis (CVS) thermodynamic niobium nanopowder FactSage software
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The complete chemical synthesis of yeast chromosome Ⅻ
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《Science Foundation in China》 CAS 2017年第2期1-,共1页
Subject Code:C06 With the support by the National Natural Science Foundation of China,a study by the research group led by Prof.Dai Junbiao(戴俊彪)from Tsinghua University reported the complete chemical synthesis of t... Subject Code:C06 With the support by the National Natural Science Foundation of China,a study by the research group led by Prof.Dai Junbiao(戴俊彪)from Tsinghua University reported the complete chemical synthesis of the yeast chromosome XII,which was published in Science(2017,355:1049—1055).To understand the origin of life,scientists have long been challenged whether an artificial living 展开更多
关键词 The complete chemical synthesis of yeast chromosome RDNA
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Synthesis and Characterization of Y-Doped Mesoporous CeO_2 Using A Chemical Precipitation Method 被引量:5
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作者 宋晓岚 江楠 +2 位作者 李宇焜 徐大余 邱冠周 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第4期428-433,共6页
Using cetyltrimethylammonium bromide (CTAB) as the template agent, cerium nitrate as the cerium resource, yttrium nitrate as the yttrium resource, and ammonium carbonate as the precipitating agent, mesoporous CeO2 p... Using cetyltrimethylammonium bromide (CTAB) as the template agent, cerium nitrate as the cerium resource, yttrium nitrate as the yttrium resource, and ammonium carbonate as the precipitating agent, mesoporous CeO2 powders doped with different yttrium contents were successfully synthesized using a chemical precipitation method, under an alkalescent condition. Properties of the obtained samples were characterized and analyzed with X-ray diffraction (XRD), energy dispersive analysis of X-rays (EDAX), transmission electron microscopy (TEM), infrared (IR) absorbance, and the BET method. For the prepared samples with 20% (molar ratio) Y-doped content, a BET specific surface area of 106. 6 m^2 · g^- 1, with an average pore size of3~27 nm were obtained. XRD patterns showed that the doped samples were with a cubic fluorite structure. TEM micrographs revealed that the doped samples showed a spherical morphology with a diameter ranging from 20 to 30 nm and a round pore shape. IR results indicated that the Ce-O-Ce vibration intensity decreased as the Y-doped content increased. N2 adsorption-desorption isotherms showed that the samples possessed typical mesopore characteristics. The average pore size of the samples decreased alter mesoporous CeO2 was doped with yttrium, and the average pore size decreased largely as the Y-doped content increased. 展开更多
关键词 mesoporous ceria Y-doped chemical precipitation method synthesis characterization rare earths
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Synthesis of steel slag ceramics: chemical composition and crystalline phases of raw materials 被引量:3
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作者 Li-hua Zhao Wei Wei +2 位作者 Hao Bai Xu Zhang Da-qiang Cang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2015年第3期325-333,共9页
Two types of porcelain tiles with steel slag as the main raw material (steel slag ceramics) were synthesized based on the CaO-A1203-SiO2 and CaO--MgO-SiO2 systems, and their bending strengths up to 53.47 MPa and 99.... Two types of porcelain tiles with steel slag as the main raw material (steel slag ceramics) were synthesized based on the CaO-A1203-SiO2 and CaO--MgO-SiO2 systems, and their bending strengths up to 53.47 MPa and 99.84 MPa, respectively, were obtained. The presence of anorthite, a-quartz, magnetite, and pyroxene crystals (augite and diopside) in the steel slag ceramics were very different from the composition of traditional ceramics. X-ray diffraction (XRD) and electron probe X-ray microanalysis (EPMA) results illustrated that the addition of steel slag reduced the temperature of extensive liquid generation and further decreased the firing temperature. The considerable contents of glass-modifying oxide liquids with rather low viscosities at high temperature in the steel slag ceramic adobes promoted element diffusion and crystallization. The results of this study demonstrated a new approach for extensive and effective recycling of steel slag. 展开更多
关键词 ceramic materials synthesis steel slag chemical composition crystalline phases solid waste recycling
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Discovery, structure,and chemical synthesis of disulfide-rich peptide toxins and their analogs 被引量:3
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作者 Ge-Min Fang Xiao-Xu Chen +4 位作者 Qian-Qian Yang Liang-Jing Zhu Ning-Ning Li Hai-Zhu Yu Xiang-Ming Meng 《Chinese Chemical Letters》 SCIE CAS CSCD 2018年第7期1033-1042,共10页
Recently, medicinal peptide molecules are of great interest to many international pharmaceutical companies, mainly because of their relatively lower research costs, shorter research cycles, and the greater likelihood ... Recently, medicinal peptide molecules are of great interest to many international pharmaceutical companies, mainly because of their relatively lower research costs, shorter research cycles, and the greater likelihood of being drugs, when compared with traditional small molecules. Due to the great variety in molecule structures and the diverse biological functions, disulfide-rich peptide toxins have become a shining molecular library for the development of polypeptide drugs. In view of the increasing amount of related publications, here we summarize the discovery, structural elucidation and chemical synthesis of disulfide-rich peptide toxins and their analogs. 展开更多
关键词 Peptide toxins CONOTOXINS CYCLOTIDES Disulfide mimics chemical synthesis
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Fischer–Tropsch synthesis using Co and Co-Ru bifunctional nanocatalyst supported on carbon nanotube prepared via chemical reduction method 被引量:2
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作者 Jafar Shariati Ali Haghtalab Amir Mosayebi 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第1期9-22,共14页
We used a chemical reduction method to synthesize the catalysts of cobalt(Co) and cobalt-ruthenium(Co-Ru) bifunctional supported on carbon nanotubes(CNTs) for Fischer–Tropsch synthesis(FTS) in a fixedbed reactor. The... We used a chemical reduction method to synthesize the catalysts of cobalt(Co) and cobalt-ruthenium(Co-Ru) bifunctional supported on carbon nanotubes(CNTs) for Fischer–Tropsch synthesis(FTS) in a fixedbed reactor. These Co-Ru/CNTs catalysts were synthesized with various weight proportions of Ru/Co(0.1 to 0.4 wt%) with keeping a fixed amount of cobalt(10 wt%). Moreover, for comparison purpose, CNTs supported Co-and Co(Ru)-based catalysts at same loading as the above catalysts were prepared through impregnation method. We characterize the present catalysts through the various techniques such as Energy–dispersive X-ray(EDX), Transmission Electron Microscopy(TEM), Brunauer–Emmett–Teller(BET),Hydrogen-Temperature-Programmed Reduction(H_2-TPR), Hydrogen-Temperature-Programmed Desorption(H_2-TPD) and O_2 titration. Thus using the chemical reduction method, a narrow particle size distribution was obtained so that the small cobalt particles were confined inside the CNTs. The Co-based catalyst prepared by impregnation was compared with the Co-Ru catalysts at the same loading. The results demonstrated that the use of chemical reduction method led to decrease the average Co oxide cluster size to8.7 nm so that the reduction enhanced about 24% and stabilized an earlier time at the stream. Among the prepared catalysts, the results indicated that the Co-Ru/CNTs catalysts demonstrated high catalytic activity with the highest long-chain hydrocarbons(C_(5+)), selectivity up to 74.76%, which was higher than those we obtained by the Co-Ru/γ-Al_2O_3(61._20%), Co/CNTs(43.68%) and Co/γ-Al_2O_3(37.69%). At the same time, comparing with those catalyst synthesized by impregnation, the use of chemical reduction led to enhancement of the C_(5+) selectivity from 59.30% to 68.83% and increment in FTS rate about 11% for the Co-Ru/CNTs catalyst. 展开更多
关键词 Cobalt-ruthenium Carbon nanotubes FISCHER-TROPSCH synthesis Catalyst nanoparticles chemical reduction method
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Chemical synthesis of nanocrystalline ZrO_2-SnO_2 composite powders 被引量:1
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作者 YANG Huaming ZHANG Xiangchao +2 位作者 YANG Wuguo HUANG Chenghuan QIU Guanzhou Department of Inorganic Materials, School of Resources Processing and Bioengineering, Central South University, Changsha 410083, China 《Rare Metals》 SCIE EI CAS CSCD 2004年第2期182-184,共3页
ZrO_2-SnO_2 composite nanoparticles were prepared by heating the hydrateprecursors synthesized by the chemical co-precipitation reaction of ZrOCl_2 and SnCl_4. Theprecursors were examined by differential thermal analy... ZrO_2-SnO_2 composite nanoparticles were prepared by heating the hydrateprecursors synthesized by the chemical co-precipitation reaction of ZrOCl_2 and SnCl_4. Theprecursors were examined by differential thermal analysis (DTA) and thermogravimetric analysis(TGA). The composite powder was characterized using X-ray diffraction (XRD), transmission electronmicroscopy (TEM) and desorption isotherm (Barrett-Joyner-Halenda method). The average crystal sizeof the nanoparticle ranges from 15 to 30 nm for the sample containing 5%-25% ZrO_2 (mass fraction).Most of the pores in the ZrO_2-SnO_2 nanoparticles are about 10-20 nm in diameter. The compositepowder is promising for chemical sensors. 展开更多
关键词 inorganic materials ZrO_2-SnO_2 nanocomposites chemical synthesis DOPING pore structure
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Synthesis of Cell Adhesive Motif RGD Tripeptide by a Novel Chemical Method and Its Purification 被引量:1
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作者 WANG Hua ZHAO Mi-feng +6 位作者 MA Cheng-yun JING Wei HUANG Yi-bing HOU Rui-zhen ZENG Hong-bin XU Li ZHANG Xue-zhong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2006年第5期612-616,共5页
The cell adhesive motif RGD tripeptide was synthesized by using a novel chemical method. First, Gly-Asp(GD) was synthesized in two steps including the chloroacetylation of free L-aspartic acid and the ammonolysis of... The cell adhesive motif RGD tripeptide was synthesized by using a novel chemical method. First, Gly-Asp(GD) was synthesized in two steps including the chloroacetylation of free L-aspartic acid and the ammonolysis of the chloroacetylated L-aspartic acid. The yield of chloroacetylated L-aspartic acid was 83.0%. For the ammonolysis of chloroacetylated L-aspartic acid, the yield of the ammonolyzed product was 92. 3%. Second, the coupling between Arg and Gly-Asp was carried out by using the NCA method. The maximum yield of RGD was about 50% at 0℃ and pH = 9. 5. The prepared RGD tripeptide was confirmed by using amino acid component analysis and mass spectrographic analysis. 展开更多
关键词 RGD tripeptide chemical synthesis Purification Arg-Gly-Asp
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