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小鼠胚胎库的现状及胚胎和配合子冷冻保存的应用前景 被引量:4
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作者 徐平 《上海实验动物科学》 2001年第1期49-55,共7页
近年来 ,逐渐增多的小鼠突变系资源已对现有的动物设施和品种 (系 )的保存方法提出严峻的挑战。小鼠胚胎和配合子的低温保存是目前保存小鼠种群资源中应用最为广泛的方法 ,通过低温保存不仅使原有的或新开发的小鼠品系得以安全的、长期... 近年来 ,逐渐增多的小鼠突变系资源已对现有的动物设施和品种 (系 )的保存方法提出严峻的挑战。小鼠胚胎和配合子的低温保存是目前保存小鼠种群资源中应用最为广泛的方法 ,通过低温保存不仅使原有的或新开发的小鼠品系得以安全的、长期的保存下来 ,同时也使这些小鼠模型的规模化生产、推广普及变得更为简单化。无疑 ,小鼠模型的保存将为 2 展开更多
关键词 小鼠模型 冷冻保存 胚胎 配合子 胚胎
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铅-没食子酸配合物分子印迹传感器的研制及应用 被引量:1
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作者 杨志 庞官荣 李建平 《分析科学学报》 CAS CSCD 北大核心 2015年第4期470-474,共5页
本文制备了一种基于分子印迹技术的电化学传感器,并成功应用于环境水样中Pb(Ⅱ)的检测。以铅-没食子酸配合物(Pb—Gal)为模板分子,用电聚合邻苯二胺(o-PD)的方法在铂电极上聚合了Pb—Gal分子印迹聚合物膜。根据印迹膜对Pb—Gal... 本文制备了一种基于分子印迹技术的电化学传感器,并成功应用于环境水样中Pb(Ⅱ)的检测。以铅-没食子酸配合物(Pb—Gal)为模板分子,用电聚合邻苯二胺(o-PD)的方法在铂电极上聚合了Pb—Gal分子印迹聚合物膜。根据印迹膜对Pb—Gal的识别作用对Pb(Ⅱ)进行间接测定。以K3[Fe(CN)6]/K4[Fe(CN)6]为探针,利用其氧化还原电流信号变化实现对Pb(Ⅱ)的检测。通过对配合物整体的识别,提高了检测的灵敏度。研究表明,在0.03~30nmol/L范围内,Pb(Ⅱ)浓度的对数值(IgCPb(Ⅱ)与氧化峰电流变化值(△i)呈线性关系,检出限为0.0163nmol/L。 展开更多
关键词 印迹技术 电化学传感器 Pb(Ⅱ) 铅-没食配合
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铜(Ⅱ)-没食子酸配合物的抑菌活性研究 被引量:1
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作者 滕李濛 宋卓芮 +2 位作者 毕家豪 付煜荣 杨文 《广东化工》 CAS 2018年第8期54-55,共2页
本文采用试管法和滴板法研究铜-没食子酸配合物的对金黄色葡萄球菌、白色念珠菌的抑菌作用。结果表明,铜(Ⅱ)-没食子酸配合物对金黄色葡萄球菌和白色念珠菌均有抑制作用,且对前者抑制作用比后者强;对金黄色葡萄球菌的最小抑菌浓度为0.03... 本文采用试管法和滴板法研究铜-没食子酸配合物的对金黄色葡萄球菌、白色念珠菌的抑菌作用。结果表明,铜(Ⅱ)-没食子酸配合物对金黄色葡萄球菌和白色念珠菌均有抑制作用,且对前者抑制作用比后者强;对金黄色葡萄球菌的最小抑菌浓度为0.0313 mg/mL,最小杀菌浓度为0.250 mg/mL;对白色念珠菌的最小抑菌浓度为1.00 mg/mL,最小杀菌浓度为2.00 mg/mL。 展开更多
关键词 铜(Ⅱ)-没食配合 金黄色葡萄球菌 白色念珠菌 抑菌
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Theoretical Studies on Structures and Spectroscopic Properties of Highly Efficient Phosphorescent [Ru(terpy)(phen)X]+ Complexes
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作者 金丽 张建坡 +1 位作者 张红星 白福全 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第4期391-398,I0003,共9页
The ground and the lowest-lying triplet excited state geometries, electronic structures, and spectroscopic properties of three mixed-ligand Ru(II) complexes [Ru(terpy)(phen)X]+ (terpy=2,2',6',2″-terpyridine... The ground and the lowest-lying triplet excited state geometries, electronic structures, and spectroscopic properties of three mixed-ligand Ru(II) complexes [Ru(terpy)(phen)X]+ (terpy=2,2',6',2″-terpyridine, phen=l,10-phenanthroline, and X=-C-=CH (1), X=Cl (2), X-CN (3)) were investigated theoretically using the density functional theory method. The ground and excited state geometries have been fully optimized at the B3LYP/LanL2DZ and UB3LYP/LanL2DZ levels, respectively. The absorption and emission spectra of the com- plexes in CHaCN solutions were calculated by time-dependent density functional theory with the PCM solvent model. The calculated bond lengths of Ru-C, Ru-N, and Ru-Cl in the ground state agree well with the corresponding experimental results. The highest occupied molecular orbital were dominantly localized on the Ru atom and monodentate X ligand for 1 and 2, Ru atom and terpy ligand for a, while the lowest unoccupied molecular orbital were π*(terpy) type orbital. Therefore, the lowest-energy absorptions of 1 and 2 at 688 and 631 nln are attributed to a dyz (Ru)+Tr/p(X)--π* (terpy) transition with MLCT/XLCT (metal-to-ligand charge transfer/X ligand to terpy ligand charge transfer) character, whereas that of 3 at 529 nm is related to a dyz (Ru)+π(terpy)-π* (terpy) transition with MLCT and ILCT transition character. The calculated phosphorescence of three complexes at 1011 nm (1), 913 nm (2), and 838 nm (3) have similar transition properties to that of the lowest-lying absorption. It is shown that the lowest lying absorptions and emissions transition character of these Ru(II) complexes can be tuned by changing the electron-withdrawing ability of the monodentate ligand. 展开更多
关键词 Mixed-ligand Ru(II) complexes Electronic structure Spectroscopic property DFT calculation UB3LYP method
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Texture Analysis of Damascene Copper Interconnects 被引量:2
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作者 王晓冬 吉元 +4 位作者 钟涛兴 李志国 夏洋 刘丹敏 肖卫强 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第6期1136-1140,共5页
Texture and grain boundary character distribution of Cu interconnects with different line width for as-deposited and annealed conditions were measured by EBSD. All specimens appear mixed texture and (111) texture is... Texture and grain boundary character distribution of Cu interconnects with different line width for as-deposited and annealed conditions were measured by EBSD. All specimens appear mixed texture and (111) texture is the dominate component.As-deposited interconnects undergo the phenomenon of self-annealing at RT,in which some abnormally large grains are found. Lower aspect ratio of lines and anneal treatment procured larger grains and stronger (111) texture. Meanwhile, the intensity proportion of other textures with lower strain energy to (111) texture is decreased. As-deposited specimens reveal (111)(112? and (111) (231) components, (111) (110) component appeared and (111) (112? and (111) (231) components were developed during the annealing process. High angle boundaries are dominant in all specimens, boundaries with a misorientation of 55°-60° and ∑3 ones in higher proportion, followed by lower boundaries with a misorientation of 35°-40° and 29 boundaries. As the aspect ratio of lines and anneal treatment increase,there is a gradual in- crement in ∑3 boundaries and a decrease in ∑9 boundaries. 展开更多
关键词 Cu interconnects TEXTURE MISORIENTATION coincident site lattice boundaries EBSD
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Advances in Small RNAs and Sexual Reproduction in Plants
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作者 王俊 何桥 +5 位作者 汪卫星 向素琼 孙海艳 李晓林 梁国鲁 郭启高 《Agricultural Science & Technology》 CAS 2013年第2期211-214,229,共5页
Small RNAs are non-coding RNA molecules with 20-30 nucleotides (nt) in length that mainly play regulatory roles in gene expression at the post-transcription level by directly cutting target mRNA or inhibiting its tr... Small RNAs are non-coding RNA molecules with 20-30 nucleotides (nt) in length that mainly play regulatory roles in gene expression at the post-transcription level by directly cutting target mRNA or inhibiting its translation. Small RNAs play regulatory roles in the growth and development process of plants at the core of gene regulatory networks, which has been widely studied and confirmed in sporophyte generation of plants. However, few researches have been conducted on small RNAs and gametophyte generation. It is reported that small RNAs play important roles in floral organ development, gametogenesis, fertilization, and early zygotic development of plants. In addition, various small RNAs also play roles in controlling genetic integrity, cell differentiation and functions during the sexual reproduction process of plants. However, most of the specific functions of small RNAs in the sexual reproduction process are unknown yet. This study mainly aimed to introduce small RNAs in plants, summarize the latest advances in researches of small RNAs and plant sexual reproduction, and make prospect on its future. 展开更多
关键词 Small RNA Sexual reproduction Floral organ development GAMETOGENESIS FERTILIZATION Early zygotic development
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Catalytic epoxidation of olefin over supramolecular compounds of molybdenum oxide clusters and a copper complex 被引量:3
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作者 高洪成 颜岩 +5 位作者 徐晓弘 于杰辉 牛会玲 高文秀 张文祥 贾明君 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2015年第11期1811-1817,共7页
The catalytic epoxidation of olefin was investigated on two copper complex-modified molybdenum oxides with a 3D supramolecular structure, [Cu(bipy)]4[Mo15O47].2H2O (1) and [Cu1(bix)][(Cu1bix) (δ-MoVl8O26)0.... The catalytic epoxidation of olefin was investigated on two copper complex-modified molybdenum oxides with a 3D supramolecular structure, [Cu(bipy)]4[Mo15O47].2H2O (1) and [Cu1(bix)][(Cu1bix) (δ-MoVl8O26)0.5] (2) (bipy = 4,4'-bipyridine, bix = 1,4-bis(imidazole-1-ylmethyl)benzene). Both compounds were catalytically active and stable for the epoxidation of cyclooctene, 1-octene, and styrene with tert-butyl hydroperoxide (t-BuOOH) as oxidant. The excellent catalytic performance was attributed to the presence of stable coordination bonds between the molybdenum oxide and copper complex, which resulted in the formation of easily accessible Mo species with high electropositivity. In addition, the copper complex also acted as an active site for the activation of t-BuOOH, thus im- proving these copper complex-modified polyoxometalates. 展开更多
关键词 Supramolecular compound Molybdenum oxide cluster Copper complex Olefin Epoxidation
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Thermal-hydro-mechanical coupling stress intensity factor of brittle rock 被引量:3
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作者 李鹏 饶秋华 +1 位作者 李卓 敬静 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第2期499-508,共10页
A new calculation formula of THM coupling stress intensity factor was derived by the boundary collocation method, in which an additional constant stress function was successfully introduced for the cracked specimen wi... A new calculation formula of THM coupling stress intensity factor was derived by the boundary collocation method, in which an additional constant stress function was successfully introduced for the cracked specimen with hydraulic pressure applied on its crack surface. Based on the newly derived formula, THM coupling fracture modes (including tensile, shear and mixed fracture mode) can be predicted by a new fracture criterion of stress intensity factor ratio, where the maximum axial load was measured by self-designed THM coupling fracture test. SEM analyses of THM coupling fractured surface indicate that the higher the temperature and hydraulic pressure are and the lower the confining pressure is, the more easily the intergranular (tension) fracture occurs. The transgranular (shear) fracture occurs in the opposite case while the mixed-mode fracture occurs in the middle case. The tested THM coupling fracture mechanisms are in good agreement with the predicted THM coupling fracture modes, which can verify correction of the newly-derived THM coupling stress intensity factor formula. 展开更多
关键词 stress intensity factor thermal-hydro-mechanical coupling boundary collocation method fracture mechanism brittle rock
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A method for calculation of ion distribution in reaction system forming hydroxide
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作者 金哲男 郑大录 +3 位作者 洪正秀 郑英勋 路殿坤 陈国宝 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第12期3793-3798,共6页
A formula was proposed to calculate the distribution of metal ions quantitatively in chemical reaction system forming hydroxide where precipitation and complex are formed together. The effects of some factors on forma... A formula was proposed to calculate the distribution of metal ions quantitatively in chemical reaction system forming hydroxide where precipitation and complex are formed together. The effects of some factors on formation of precipitation and complex were investigated, and the corresponding precipitation rates of zinc, iron (III), aluminum, copper and magnesium were calculated. As a result, it shows that the proposed formula is reliable. By the proposed formula, the existence state of metal ions in hydroxides reaction system with any metal ions can be well described and the effects of some factors on the distribution of metal ions were determined. 展开更多
关键词 HYDROXIDE metal ions distribution precipitation rate complex forming rate
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Ionic palladium complex as an efficient and recyclable catalyst for the carbonylative Sonogashira reaction 被引量:1
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作者 杨妲 王栋梁 +4 位作者 刘欢 赵小莉 路勇 赖时军 刘晔 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第3期405-411,共7页
The neutral palladium(Ⅱ) complex bis-[1-(5'-diphenylphosphinothiazol-2'-yl)-imidazolyl]dichloropalladium(Ⅱ)(1A) ligated by thiazolylimidazolyl-based phosphine(L1) in which thiazolylimidazolyl acted as an... The neutral palladium(Ⅱ) complex bis-[1-(5'-diphenylphosphinothiazol-2'-yl)-imidazolyl]dichloropalladium(Ⅱ)(1A) ligated by thiazolylimidazolyl-based phosphine(L1) in which thiazolylimidazolyl acted as an S- and N-donor provider with weak coordinating nature,and the ionic complex bis-[1-(5'-diphenylphosphinothiazol-2'-yl)-3-methylimidazolium]dichloropalladium(Ⅱ) trifluoromethanesulfonate(2A) ligated by thiazolylimidazolium-based phosphine(L2) after quaternization of L1 using methyl trifluoromethanesulphonate were synthesized.It was found that the introduced positive charges and strong electron-withdrawing effect in 2A not only led to changes in the configuration and structural stability of the complex,but also lowered its catalytic performance in carbonylative Sonogashira reactions.These effects reveal the important role of the N-donor in 1A.In addition,as an ionic palladium complex,2A combined with the room-temperature ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate could be recycled eight times as the catalyst in carbonylative Sonogashira reactions without detectable metal leaching. 展开更多
关键词 Ionic phosphine ligand Palladium complex Carbonylative Sonogashira reaction Ionic liquid
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O-O bond formation mechanisms during the oxygen evolution reaction over synthetic molecular catalysts 被引量:4
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作者 Xue-Peng Zhang Hong-Yan Wang +2 位作者 Haoquan Zheng Wei Zhang Rui Cao 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第8期1253-1268,共16页
Water oxidation is one of the most important reactions in natural and artificial energy conversion schemes.In nature,solar energy is converted to chemical energy via water oxidation at the oxygen-evolving center of ph... Water oxidation is one of the most important reactions in natural and artificial energy conversion schemes.In nature,solar energy is converted to chemical energy via water oxidation at the oxygen-evolving center of photosystem II to generate dioxygen,protons,and electrons.In artificial energy schemes,water oxidation is one of the half reactions of water splitting,which is an appealing strategy for energy conversion via photocatalytic,electrocatalytic,or photoelectrocatalytic processes.Because it is thermodynamically unfavorable and kinetically slow,water oxidation is the bottleneck for achieving large-scale water splitting.Thus,developing highly efficient water oxidation catalysts has attracted the interests of researchers in the past decades.The formation of O-O bonds is typically the rate-determining step of the water oxidation catalytic cycle.Therefore,better understanding this key step is critical for the rational design of more efficient catalysts.This review focuses on elucidating the evolution of metal-oxygen species during transition metal-catalyzed water oxidation,and more importantly,on discussing the feasible O-O bond formation mechanisms during the oxygen evolution reaction over synthetic molecular catalysts. 展开更多
关键词 Oxygen evolution reaction Water oxidation O-O bond formation Transition metal complex Molecular electrocatalysis Reaction mechanism
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Efficient and stable Ru(Ⅲ)-choline chloride catalyst system with low Ru content for non-mercury acetylene hydrochlorination 被引量:7
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作者 Hang Li Botao Wu +4 位作者 Jianhui Wang Fumin Wang Xubin Zhang Gang Wang Haichao Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第11期1770-1781,共12页
Herein,we report an excellent,supported Ru(III)‐ChCl/AC catalyst with lower Ru content,where the ionic complex ChRuCl4 serves as the active component for acetylene hydrochlorination.The prepared heterogeneous Ru‐10%... Herein,we report an excellent,supported Ru(III)‐ChCl/AC catalyst with lower Ru content,where the ionic complex ChRuCl4 serves as the active component for acetylene hydrochlorination.The prepared heterogeneous Ru‐10%ChCl/AC catalyst shows excellent activity and long‐term stability.In this system,ChCl provides an environment for the ChRuCl4 to be stabilized as Ru(III),thus suppressing the reduction of the active species and the aggregation of ruthenium species during the reaction.The interaction between reactants and catalyst species was investigated by catalyst characterizations in combination with DFT calculations to disclose the effect of the ChRuCl4 complex and ChCl on the catalytic performance.This inexpensive,efficient,and long‐term catalyst is a competitive candidate for application in the hydrochlorination industry. 展开更多
关键词 Acetylene hydrochlorination Catalytic activity Heterogeneous catalysis Ionic complex RUTHENIUM
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Multinuclear Nuclear Magnetic Resonance Studies of 〔VS_4 (CuPPh_3)_5 (CuCl) Br_2〕 被引量:2
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作者 CHEN Zhong YE Jian-Liang CAI Shu-Hui(The Research Laboratory of SEDC of Analytical Science for Material and Life Chemistry(Department of Chemistry, Xiamen University, Xiamen 361005)(State Key Laboratory of Structural Chemistry, Fuzhou 350002)ZHENG Fa-Ku 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1998年第2期89-93,共5页
The structure, spectroscopic properties and chemical stability of [VS4-(CuPPh3)3 (CuCl)Br2] in CDCl3 solution have been studied by multinuclear NMR tech-nique. Two peaks with relative intensity of 1: 4 are found in th... The structure, spectroscopic properties and chemical stability of [VS4-(CuPPh3)3 (CuCl)Br2] in CDCl3 solution have been studied by multinuclear NMR tech-nique. Two peaks with relative intensity of 1: 4 are found in the31P-{1H} spectra.Some 13C-{1H} and 1H NMR peaks have the same integral intensity ratio. These com-plemented the results of 31P-{1H} NMR. The experimental results demonstrates that the PPh3 ligand bound to Cu(6) is not equivalent with the four PPh3 ligands bound toCu(2) ~Cu (5 )- It affords an evidence that the title compound in the solution keepssimilar structure to solid state. 展开更多
关键词 nuclear magnetic resonance V-Cu-S cluster transition metal complex
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Multiple objective particle swarm optimization technique for economic load dispatch 被引量:2
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作者 赵波 曹一家 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第5期420-427,共8页
A multi-objective particle swarm optimization (MOPSO) approach for multi-objective economic load dispatch problem in power system is presented in this paper. The economic load dispatch problem is a non-linear constrai... A multi-objective particle swarm optimization (MOPSO) approach for multi-objective economic load dispatch problem in power system is presented in this paper. The economic load dispatch problem is a non-linear constrained multi-objective optimization problem. The proposed MOPSO approach handles the problem as a multi-objective problem with competing and non-commensurable fuel cost, emission and system loss objectives and has a diversity-preserving mechanism using an external memory (call “repository”) and a geographically-based approach to find widely different Pareto-optimal solutions. In addition, fuzzy set theory is employed to extract the best compromise solution. Several optimization runs of the proposed MOPSO approach were carried out on the standard IEEE 30-bus test system. The results revealed the capabilities of the proposed MOPSO approach to generate well-distributed Pareto-optimal non-dominated solutions of multi-objective economic load dispatch. Com- parison with Multi-objective Evolutionary Algorithm (MOEA) showed the superiority of the proposed MOPSO approach and confirmed its potential for solving multi-objective economic load dispatch. 展开更多
关键词 Economic load dispatch Multi-objective optimization Multi-objective particle swarm optimization
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Photoelectron Imaging of AgOCH3- and Ag-(CH3OH)x (x=l, 2)
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作者 池超贤 谢华 +2 位作者 从然 唐紫超 周鸣飞 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第5期557-562,I0003,共7页
The AgOCH3- and Ag-(CH3OH)x(x=l, 2) anions are studied by photoelectron imaging as well as ab initio calculations. The adiabatic and vertical detachment energies (ADE and VDE) of AgOCH3- are determined as 1.29(... The AgOCH3- and Ag-(CH3OH)x(x=l, 2) anions are studied by photoelectron imaging as well as ab initio calculations. The adiabatic and vertical detachment energies (ADE and VDE) of AgOCH3- are determined as 1.29(2) and 1.34(2) eV, respectively, from the vibrational resolved photoelectron spectrum. The Ag-(CH3OH)l,2 anionic complexes are characterized as metal atomic anion solvated by the CH3OH molecules with the electron mainly localized on the metal. The photoelectron spectra of Ag-(CH3OH)x (x=O, 1, 2) show a gradual increase in VDE with increasing x, due to the solvent stabilization. Evidence for the methanol-methanol hydrogen bonding interactions appears when the Ag- is solvated by two methanol molecules. 展开更多
关键词 Silver methanol complex SOLVATION Photoelectron imaging Density functionalcalculation
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Sexual Fusion and Life History of Scytosiphon lomentaria (Scytosiphonaceae, Phaeophyceae) in Dalian, China 被引量:1
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作者 LI Xiaoli ZHANG Zeyu +1 位作者 DONG Shuanglin CAO Shuqing 《Journal of Ocean University of China》 SCIE CAS 2011年第2期170-176,共7页
Morphology and life history of a brown alga Scytosiphon lomentaria (Lyngbye) Link (Scytosiphonaceae, Phaeophyceae) were investigated from 2005 to 2009 in the coastal waters of Dalian, China. The erect thalli collected... Morphology and life history of a brown alga Scytosiphon lomentaria (Lyngbye) Link (Scytosiphonaceae, Phaeophyceae) were investigated from 2005 to 2009 in the coastal waters of Dalian, China. The erect thalli collected in the field were tubular, hollow, and commonly constricted at intervals. Ascocysts were presented. Plurilocular gametangia, which were positioned in continuous sori on the erect thallus surface, produced biflagellar gametes. Gametophytes were dioecious and gametes were nearly isogamous. Gametes fusion occurred in three types. Type one, female and male gametes fused directly while swimming; type two, female gamete settled first, with which a male one contacted and fused rapidly; type three, while settling adjacently, a male gamete's entire protoplast moved slowly into the previously settled female one, with only an empty cell membrane left. In culture zygotes developed into crustose sporophytes that formed unilocular sporangia. Biflagellar zoospores developed into erect thalli that formed plurilocular gametangia. The results indicated that a periodical heteromorphic alternation history with haploid gametophyte generation and diploid sporophyte generation exists in S. lomentaria of the Dalian populations. 展开更多
关键词 sexual fusion life history MORPHOLOGY Scytosiphon lomentaria
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Infrared Photodissociation Spectroscopy of Ti+(CO2)2Ar and Ti+(CO2)n (n=3-7) Complexes 被引量:1
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作者 Xiao-peng Xing Guan-jun Wang +1 位作者 Cai-xia Wang Ming-fei Zhou 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第6期687-693,I0004,共8页
Ti+(CO2)2Ar and Ti+(CO2)n (n=3-7) complexes are produced by laser vaporization in a pulsed supersonic expansion. The ion complexes of interest are each mass-selected in a time- of-flight spectrometer, and stud... Ti+(CO2)2Ar and Ti+(CO2)n (n=3-7) complexes are produced by laser vaporization in a pulsed supersonic expansion. The ion complexes of interest are each mass-selected in a time- of-flight spectrometer, and studied with infrared photodissociation spectroscopy. For each complex, a sharp band in the CO stretching frequency region is observed, which confirms the formation of the OTi+CO(CO2)~_l oxide-carbonyl species. Small OTi+CO(CO2)~_1 complexes (n_〈5) exhibit CO stretching and antisymmetric CO2 stretching vibrational bands that are blue-shifted from those of free CO and CO2. The experimental observations indicate that the coordination number of CO and CO2 molecules around TiO+ is five. Evidence is also observed for the presence of another electrostatic bonding Ti+(CO2)2 structural isomer for the Ti+(CO2)2Ar complex, which is characterized to have a bent OCO-Ti+-OCO structure stabilized by argon coordination. 展开更多
关键词 Infrared photodissociation spectroscopy Carbon dioxide complex TITANIUM Insertion reaction Density functional calculation
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Catalytic effects of [Ag(H_2O)(H_3PW_(11)O_(39))]^(3-)on a TiO_2 anode for water oxidation 被引量:1
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作者 Jiansheng Li Lei Wang +3 位作者 Wansheng You Meiying Liu Lancui Zhang Xiaojing Sang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第3期534-541,共8页
A[H3AgI(H2O)PW11O39]3?‐TiO2/ITO electrode was fabricated by immobilizing a molecular polyoxometalate‐based water oxidation catalyst,[H3AgI(H2O)PW11O39]3?(AgPW11),on a TiO2electrode.The resulting electrode was charac... A[H3AgI(H2O)PW11O39]3?‐TiO2/ITO electrode was fabricated by immobilizing a molecular polyoxometalate‐based water oxidation catalyst,[H3AgI(H2O)PW11O39]3?(AgPW11),on a TiO2electrode.The resulting electrode was characterized by X‐ray powder diffraction,scanning electron microscopy,and energy dispersive X‐ray spectroscopy.Linear sweep voltammetry,chronoamperometry,and electrochemical impedance measurements were performed in aqueous Na2SO4solution(0.1molL?1).We found that a higher applied voltage led to better catalytic performance by AgPW11.The AgPW11‐TiO2/ITO electrode gave currents respectively10and2.5times as high as those of the TiO2/ITO and AgNO3‐TiO2/ITO electrodes at an applied voltage of1.5V vs Ag/AgCl.This result was attributed to the lower charge transfer resistance at the electrode‐electrolyte interface for the AgPW11‐TiO2/ITO electrode.Under illumination,the photocurrent was not obviously enhanced although the total anode current increased.The AgPW11‐TiO2/ITO electrode was relatively stable.Cyclic voltammetry of AgPW11was performed in phosphate buffer solution(0.1mol L?1).We found that oxidation of AgPW11was a quasi‐reversible process related to one‐electron and one‐proton transfer.We deduced that disproportionation of the oxidized[H2AgII(H2O)PW11O39]3?might have occurred and the resulting[H3AgIIIOPW11O39]3?oxidized water to O2. 展开更多
关键词 Water oxidation ELECTROCATALYSIS PHOTOELECTROCHEMISTRY TIO2 POLYOXOMETALATE Ag+ complex
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Triangular Halogen Bond and Hydrogen Bond Supramolecular Complex Consisting of Carbon Tetrabromide, Halide, and Solvent Molecule: A Theoretical and Spectroscopic Study
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作者 Yu-jie Wu Xiao-ran Zhao +1 位作者 Hai-yue Gao Wei-jun Jin 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第3期265-273,共9页
The theoretical calculation and spectroscopic experiments indicate a kind of triangular three bonding supramolecular complexes CBr4…X^-…-H-C, which consist of carbon tetrabromide, halide, and protic solvent molecule... The theoretical calculation and spectroscopic experiments indicate a kind of triangular three bonding supramolecular complexes CBr4…X^-…-H-C, which consist of carbon tetrabromide, halide, and protic solvent molecule (referring to dichloromethane, chloroform and acetonitrile), can be formed in solution. The strength of halogen and hydrogen bonds in the triangular complexes using halide as common acceptor obeys the order of iodide〉bromide〉chloride. The halogen and hydrogen bonds work weak-cooperatively. Charge transfer bands of halogen bonding complexes between CBra and halide are observed in UV-Vis absorption spectroscopy in three solvents, and then the stoichiometry of 1:1, formation constants K and molar extinction coefficients ε of the halogen bonding complexes are obtained by Benesi-Hildebrand method. The K and ε show a dependence on the solvent dielectric constant and, on the whole, obey an order of iodide〉bromide〉chloride in the same solvents. Furthermore, the C-H vibrational frequencies of solvent molecules vary obviously with the addition of halide, which indicates the C-H…X- interaction. The experimental data indicate that the halogen bond and hydrogen bond coexist by sharing a common halide acceptor as predicted by calculation. 展开更多
关键词 Halogen bond Hydrogen bond HALIDE Carbon tetrabromide Charge transfer
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New tricks for an old dog: Visible light-driven hydrogen production from water catalyzed by fac-and mer-geometrical isomers of tris(thiosemicarbazide) cobalt(Ⅲ)
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作者 Yang Zhao Yongheng Wang +5 位作者 Qiaoyu Wu Jinqing Lin Shenghui Wu Wenjuan Hou Ruibo Wu Genggeng Luo 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第3期517-526,共10页
Increasing interest has been paid to the development of earth‐abundant metal complexes as promising surrogates of platinum for the electrocatalytically and photocatalytically driven hydrogen evolution reaction.In thi... Increasing interest has been paid to the development of earth‐abundant metal complexes as promising surrogates of platinum for the electrocatalytically and photocatalytically driven hydrogen evolution reaction.In this work,we report on molecular H2‐evolving catalysts based on two octahedral complexes of cobalt thiosemicarbazide,fac‐[Co(Htsc)3]Cl3·3H2O(C1,Htsc=thiosemicarbazide)and mer‐[Co(Htsc)3]Cl3·4H2O(C2),which have facial(fac)and meridional(mer)geometry,respectively.Electrochemical studies confirmed that both C1and C2are active electrocatalysts in MeOH solution using acetic acid as the proton source,with the same overpotential of^640mV and TOF of^210s–1.The complex C1also exhibits electrocatalytic activity for hydrogen evolution reaction in aqueous media free of organic solvent with a moderate overpotential(560mV).Visible light‐driven hydrogen evolution experiments were carried out in combination with fluorescein as photosensitizer and triethylamine as sacrificial reductant in homogeneous environments.Our studies showed that both C1and C2can be used as efficient proton‐reduction catalysts in purely aqueous solution and have the same photocatalytic activities.A TOF of125h–1with a TON of900for photocatalytic H2generation using C1and C2in water were achieved for the noble‐metal‐free homogeneous system.It should be noted that this is the first reported study investigating the effect on the catalytic hydrogen production performance of using fac‐and mer‐isomers of molecular catalysts. 展开更多
关键词 THIOSEMICARBAZIDE Cobalt complexes Molecular catalysis Geometric isomers PHOTOCATALYSIS
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