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COMPLEX REACTIONS OF ETHYL-GLUCOSIDES SYNTHESIS OVER ION EXCHANGE RESIN
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作者 Tu Maobing and Wei Dongzhi (The State Key Laboratory of Bioreactor Engineering ECUST, Shanghai 200237) 《化工学报》 EI CAS CSCD 北大核心 2000年第S1期163-167,共5页
The glycosidation reactions of D-glucose with ethanol have been carried out over a reusable and separable heterogeneous catalyst, namely, ion exchange resin. Detailed kinetic data for these reactions are reported. A c... The glycosidation reactions of D-glucose with ethanol have been carried out over a reusable and separable heterogeneous catalyst, namely, ion exchange resin. Detailed kinetic data for these reactions are reported. A complex reaction model has been developed for interpreting the data. The reactions were found to be global second-order reactions and first -order with respect to each component. Meanwhile, a new regression method is applied to determine the rate constant from time-dependent profiles. 展开更多
关键词 Ethyl-glucoside solid catalyst kinetic complex reactions
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Molecular-Based Simulation of Feedstock Properties for Complex Reaction System
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作者 Ouyang Fusheng Bao Wenjun +1 位作者 Jiang Hongbo Weng Huixin (Research Center of Petroleum Processing,East China University of Science and Technology,Shanghai 200237) 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2010年第1期54-60,共7页
复杂反应系统的动力学与由集中于深催化的裂开的模拟和结构的面向的 Lumping (两重棉包线) 处理的蒙特卡罗的联合方法在分子的水平上被学习,模型参数借助于一个两重棉包线单位的平淡的分析数据被优化。一个模型被建立与蒙特卡罗模拟转... 复杂反应系统的动力学与由集中于深催化的裂开的模拟和结构的面向的 Lumping (两重棉包线) 处理的蒙特卡罗的联合方法在分子的水平上被学习,模型参数借助于一个两重棉包线单位的平淡的分析数据被优化。一个模型被建立与蒙特卡罗模拟转变象两重棉包线那样的复杂反应系统的化工物品到 1000-10000 伪分子,每个分子被 19 个属性表示。模型模拟的结果证明这些伪分子反映了化工物品的特征很好,他们的平均性质与植物数据给了一个好协议。 展开更多
关键词 复杂反应系统 分子水平 原料性能 模拟系统 催化裂解装置 集总参数模型 基础 蒙地卡罗模拟
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International study of the Complex Stress Reaction Syndrome:Implications for transdiagnostic clinical practice
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作者 Sari Goldstein Ferber Aron Weller +15 位作者 Adele M Hayes Tracy D Vannorsdall Yaroup Ajlouni Mo'nes Qudah Gil Zalsman Gal Shoval Tommaso Benedetto Jannini Racquel Fiedler Lily X Chen Danielle R Shayani Elin Kachuki Dory Dana Stolowicz-Melman Connor Evans Megan Trow Giorgio Di Lorenzo Rodolfo Rossi 《World Journal of Psychiatry》 SCIE 2023年第10期803-815,共13页
BACKGROUND The debate regarding diagnostic classification systems in psychiatry(categorial vs dimensional systems)has essential implications for the diagnosis,prevention and treatment of stress reactions.We previously... BACKGROUND The debate regarding diagnostic classification systems in psychiatry(categorial vs dimensional systems)has essential implications for the diagnosis,prevention and treatment of stress reactions.We previously found a unique pattern of stress reaction in a study executed during the coronavirus disease 2019 pandemic using large representative samples in two countries,and termed it the Complex Stress Reaction Syndrome(CSRS).AIM To investigate CSRS,Type A(psychiatric symptoms,spanning anxiety,depression,stress symptoms,and posttraumatic stress disorder(PTSD)),with or without long-coronavirus disease(COVID)residuals(CSRS,Type B,neuropsychiatric symptoms spanning cognitive deficits and fatigue,excluding systemic symptoms).Our two-tailed hypothesis was that CSRS is a condition related to an unrecognized type of stress reaction in daily life in the general population(Type A)or that it is related to the severe acute respiratory syndrome coronavirus 2 infection and its long-COVID residuals(Type B).METHODS 977 individuals in four continents(North America,Europe,Australia and the Middle East)completed the online study questionnaire in six languages using the Qualtrics platform.The study was managed by six teams in six countries that promoted the study on social media.The questionnaire assessed anxiety,depression,stress symptoms and PTSD(CSRS,Type A),cognitive deficits and fatigue(CSRS,Type B).The data were analyzed using Proportion Analyses,Multivariate Analysis of Co-Variance(MANCOVA),linear regression analyses and validated clinical cutoff points.RESULTS The results of the Proportion Analyses showed that the prevalence of 4 symptoms spanning anxiety,depression,stress symptoms,and PTSD was significantly higher than the most prevalent combinations of fewer symptoms across 4 continents,age groups,and gender.This supports the transdiagnostic argument embedded in the CSRS(Type A).The same pattern of results was found in infected/recovered individuals.The prevalence of the 4 psychiatric symptoms combination was significantly greater than that of 5 and 6 symptoms,when adding cognitive deficits and fatigue,respectively.MANCOVA showed a significant three-way interaction(age×gender×continent).Further analyses showed that the sources of this three-way interaction were threefold relating to two sub-populations at-risk:(1)Individuals that self-identified as non-binary gender scored significantly higher on all 4 psychiatric symptoms of the CSRS,Type A at young age groups(<50 years old)in North America compared to(self-identified)women and men located in the 4 continents studied,and to other ages across the adult life span;and(2)This pattern of results(CSRS,Type A)was found also in women at young ages(<40 years old)in North America who scored higher compared to men and women in other continents and other ages.Linear regression analyses confirmed the MANCOVA results.CONCLUSION These results show a combined mental health risk factor related to stress reactivity,suggesting that the CSRS is sensitive to populations at risk and may be applied to future identification of other vulnerable sub-populations.It also supports the transdiagnostic approach for more accurate prevention and treatment.Time will tell if such transdiagnostic syndromes will be part of the discussions on the next revisions of the traditional classification systems or whether the crisis in psychiatry further evolves. 展开更多
关键词 TRANSDIAGNOSTIC complex Stress reaction Syndrome Stress reactivity Affective disorders Debate in psychiatry
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Energetic and Entropic Changes in Volume Work and Chemical Reactions
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作者 Frank Diederichs 《Advances in Chemical Engineering and Science》 CAS 2024年第1期8-47,共40页
In the present study, energetic and entropic changes are investigated on a comparative basis, as they occur in the volume changes of an ideal gas in the Carnot cycle and in the course of the chemical reaction in a lea... In the present study, energetic and entropic changes are investigated on a comparative basis, as they occur in the volume changes of an ideal gas in the Carnot cycle and in the course of the chemical reaction in a lead-acid battery. Differences between reversible and irreversible processes have been worked out, in particular between reversibly exchanged entropy (∆<sub>e</sub>S) and irreversibly produced entropy (∆<sub>i</sub>S). In the partially irreversible case, ∆<sub>e</sub>S and ∆<sub>i</sub>S add up to the sum ∆S for the volume changes of a gas, and only this function has an exact differential. In a chemical reaction, however, ∆<sub>e</sub>S is independent on reversibility. It arises from the different intramolecular energy contents between products and reactants. Entropy production in a partially irreversible Carnot cycle is brought about through work-free expansions, whereas in the irreversible battery reaction entropy is produced via activated complexes, whereby a certain, variable fraction of the available chemical energy becomes transformed into electrical energy and the remaining fraction dissipated into heat. The irreversible reaction process via activated complexes has been explained phenomenologically. For a sufficiently high power output of coupled reactions, it is essential that the input energy is not completely reversibly transformed, but rather partially dissipated, because this can increase the process velocity and consequently its power output. A reduction of the counter potential is necessary for this purpose. This is not only important for man-made machines, but also for the viability of cells. 展开更多
关键词 Exchanged Entropy Entropy Production Coupled reactions Activated complexes Power Output
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Simulating Some Complex Phenomena in Hydrothermal Ore-Forming Processes by Reaction-Diffusion CNN 被引量:1
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作者 Xu Deyi Yu Chongwen Bao Zhengyu Geochemistry Institute, China University of Geosciences, Wuhan 430074 《Journal of China University of Geosciences》 SCIE CSCD 2003年第3期215-219,共5页
Complexity phenomena like dynamic and static patterns, order from disorder, chaos and catastrophe were simulated by the application of 2-D reaction-diffusion CNN of two state variables and two diffusion coefficients t... Complexity phenomena like dynamic and static patterns, order from disorder, chaos and catastrophe were simulated by the application of 2-D reaction-diffusion CNN of two state variables and two diffusion coefficients transformed from Zhabotinksii model. They revealed somehow the mechanism of hydrothermal ore-forming processes, and answered several questions about the onset of ore forming. 展开更多
关键词 hydrothermal ore forming complexity reaction-diffusion CNN
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Chitosan-immobilized Palladium Complex: a Green and Highly Active Heterogeneous Catalyst for Heck Reaction 被引量:4
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作者 PuLIU LanWANG XiangYuWANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第4期475-477,共3页
A green heterogeneous catalyst for Heck reaction-chitosan-immobilized palladium complex was prepared. The catalyst exhibits high activity and stereoselectivity under the moderate reaction conditions. The catalyst can ... A green heterogeneous catalyst for Heck reaction-chitosan-immobilized palladium complex was prepared. The catalyst exhibits high activity and stereoselectivity under the moderate reaction conditions. The catalyst can be separated easily from the reaction mixture and reused after washing. Under the suitable reaction conditions, the cross-coupling of iodobenzene (ArI) with acrylic acid (AA) or acrylate can be achieved 93.3% or 99% yield of trans-cinnamic acid or trans-cinnamic ester. 展开更多
关键词 Chitosan-immobilized palladium complex green catalyst Heck reaction.
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Suzuki reaction of bromoallenes with arylboronic acids using an air-stable palladium complex Pd(Ph_2PCH_2CO_2)_2 as a precatalyst 被引量:1
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作者 Xin Du Xiu Juan Feng +2 位作者 Ying Liu Ren He Ming Bao 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第6期641-645,共5页
Suzuki reaction of bromoallenes with arylboronic acids was successfully performed by using an air-stable hemilabile P-O coordinated cyclopalladated complex Pd(Ph_2PCH_2CO_2)_2 as a precatalyst,and the corresponding co... Suzuki reaction of bromoallenes with arylboronic acids was successfully performed by using an air-stable hemilabile P-O coordinated cyclopalladated complex Pd(Ph_2PCH_2CO_2)_2 as a precatalyst,and the corresponding coupling products were obtained in satisfactory to excellent yields.All products are unknown compounds which were characterized by ~1H NMR,^(13)C NMR,IR,and HRMS. 展开更多
关键词 Suzuki reaction Bromoallene Palladium complex
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SYTHESE AND REACTIONS OF HETEROBINUCLEAR COMPLEXES [PhCl_2SnM(Cl)(CO)_3(CH_3CN)_2] (M = Mo, W)
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作者 Ji Tao WANG Yun WenZHANG +1 位作者 Yu Ming XU Chun Ming CUI Department of Chemistry, Nankai University, 300071, Tianjin 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第7期641-644,共4页
Abstract The complexes [M(CO);(CH;CN);](M=Mo, W)react with an equimolar quantity ofPhSnCl;in dichloromethane at room tempreture to afford new heterobinuclearcomplexes [PhCl;SnM(Cl)(CO);(CH;CN);] [M=Mo(1); ... Abstract The complexes [M(CO);(CH;CN);](M=Mo, W)react with an equimolar quantity ofPhSnCl;in dichloromethane at room tempreture to afford new heterobinuclearcomplexes [PhCl;SnM(Cl)(CO);(CH;CN);] [M=Mo(1); W(2)]. The complexes reactwith two equivalents of PR;R’(R=Ph, R’=Ph, Me; R=Cy, R’=H) to yield stablecomplexes [PhCl;SnM(Cl)(CO);(PR;R’);]. Reaction of[PhCl;SnM(Cl)(CO);(CH;CN);]with one equivalent of PPh;(CH;)nPPh;(n=I,2) or bulky phosphine ligands PBu;Clin dichloromethane at room tempreture to give [PhCl;SnMo(Cl)(CO);{PPh;(CH;)n-PPh;}] .CH;Cl;, [PhCl;SnMo(Cl)(CO);PBu;Cl]. CH;Cl;, respectively. The complexes1 and 2 react with phosphite donor ligands P(OMe);to give [PhCl;SnM(Cl)(CO);-{P(OMe);};]. All complexes have been characterized by elemental analysis, IRand;HNMR spectroscopies. Here we report the preliminary results of this work. 展开更多
关键词 CI CO PhCl2SnM SYTHESE AND reactionS OF HETEROBINUCLEAR complexES CN MO CL
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Friedel-Crafts Acylation Reactions Using Catalytic SbCl_5-TEBA Complex as an Efficient Catalyst 被引量:1
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作者 AnPingHUANG XueYuanLIU +3 位作者 LianHuaLI XiaoLiWU WeiMinLIU YongMinLIANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第12期1415-1418,共4页
SbCl_5-TEBA (PhCH_2NEt_3Cl) complex catalyzes the Friedel-Crafts acylation reactionsefficiently.
关键词 Friedel-Crafts acylation reactions SbC1_5-TEBA (PhCH_2NEt_3C1) complex catalyst.
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Reactions and crystal structures of heterodinuclear complexes R_3Sn-M(CO)_5(M = Mn,Re) with some nitrogen ligands
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作者 Yong Qiang Ma Ning Yin +1 位作者 Wen Jing Peng Jing Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第4期465-468,共4页
Some reactions of R3SnM(CO)5 (M = Mn, Re) with CH3CN or pyridine were investigated to give complexes R3SnMn(CO)3LL' or R3SnMn(CO)4L by a facile mild method. X-ray diffractions analyses show that, in contrast ... Some reactions of R3SnM(CO)5 (M = Mn, Re) with CH3CN or pyridine were investigated to give complexes R3SnMn(CO)3LL' or R3SnMn(CO)4L by a facile mild method. X-ray diffractions analyses show that, in contrast to the phosphine ligand occupying in axial position, nitrogen ligands occupy equatorial position. 展开更多
关键词 reactionS Heterodinuclear complexes X-ray structure
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STUDIES ON THE CHROMOPHORIC REACTIONS OF MIXED POLYNUCLEAR COMPLEXES OF RARE EARTH-ARSENAZO Ⅲ-COPPERO-PHENANTHROLINE
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作者 沈含熙 凌蓉 《Journal of Rare Earths》 SCIE EI CAS CSCD 1990年第3期218-223,共6页
In an acidic solution the mixed polynuclear complexes could be formed by association of rareearth-arsenazo Ⅲ complexing anions with copper o-phenanthrolinate cations.In this paper the formationconditions of lanthanum... In an acidic solution the mixed polynuclear complexes could be formed by association of rareearth-arsenazo Ⅲ complexing anions with copper o-phenanthrolinate cations.In this paper the formationconditions of lanthanum-arsenazo Ⅲ-copper-o-phenanthroline complex and its related reaction mechanismhave been studied in detail.The complex exhibits an absorption maximum at 663 nm and its apparent molarabsorptivity is found to be 1.22×105L·mol-1·cm-1.The molar ratio of the components in the complex isestimated to be La:arsenazo Ⅲ:Cu:Phen=1:1:1:3.Its possible molecular formula can expressed as[Cu(Phen)3](La-arsenazo Ⅲ).The reaction is used to determine micro amounts of lanthanum(or rareearths)in copper containning synthetic samples and satisfactory results are obtained. 展开更多
关键词 La STUDIES ON THE CHROMOPHORIC reactionS OF MIXED POLYNUCLEAR complexES OF RARE EARTH-ARSENAZO COPPERO-PHENANTHROLINE
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Optically Active β-Hydroxy Carbonyl Compound from a Mukaiyama Reaction Catalyzed by M-Salen Complex
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《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期227-227,共1页
关键词 Optically Active Hydroxy Carbonyl Compound from a Mukaiyama reaction Catalyzed by M-Salen complex
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Symmetrical Palladium (II) N,N,O,O-Schiff Base Complex: Efficient Catalyst for Heck and Suzuki Reactions
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作者 Wan Nazihah Wan Ibrahim Mustaffa Shamsuddin 《Crystal Structure Theory and Applications》 2012年第3期25-29,共5页
Palladium is arguably the most versatile and most widely applied catalytic metal in the field of fine chemicals due to its high selectivity and activity. Palladium catalyst offers an abundance of possibilities of carb... Palladium is arguably the most versatile and most widely applied catalytic metal in the field of fine chemicals due to its high selectivity and activity. Palladium catalyst offers an abundance of possibilities of carbon-carbon bond formation in organic synthesis. In this research, three different Schiff base ligands have been prepared by condensation reaction between appropriate aldehyde or ketone with amine namely 2,2-dimethyl-1,3-propanediamine in the molar ratio of 2:1. The corresponding palladium (II) Schiff base complexes were prepared through the reaction between the Schiff base ligand with palladium (II) acetate in a molar ratio 1:1. FTIR, 1H-NMR and 13C-NMR spectroscopic data revealed that the ligands are N,N,O,O-tetradentate coordinated to the Pd atom through both the azomethine N atoms and phenolic O atoms. From X-ray Crystallographic analysis, it showed that the complex exists as square planar geometry. The synthesized palladium (II) Schiff base complexes were then subjected in catalytic Heck and Suzuki reaction of iodobenzene. 展开更多
关键词 PALLADIUM (II) Schiff Base complex HECK reaction Suzuki reaction
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THE STUDY OF THE REACTION OF THE QUASI-AROMATIC COMPLEX [Ni(PnAO)-6H]^(?)WITH FORMALDEHYDE: KINETICS AND MECHANISM
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作者 Bin SONG Qi Yan ZHANG Yun Ti CHEN Department of Chemistry, Nankai University, Tianjin 300071 R.K.MERMANN Department of Chemistry, University of Missouri, Columbia 65211 USA Biotechnology research center, Zhongshan University, Guangzhou, 510275. 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第5期401-402,共2页
The kinetics of the reaction of [Ni(PnAO)—6H]° with formaldehyde was studied in H_2O—CH_3OH solution under neutral condition and a complicated mechanism with three steps including competitive, consecutive and r... The kinetics of the reaction of [Ni(PnAO)—6H]° with formaldehyde was studied in H_2O—CH_3OH solution under neutral condition and a complicated mechanism with three steps including competitive, consecutive and reverse reactions was proposed. 展开更多
关键词 ACH KINETICS AND MECHANISM PnAO THE STUDY OF THE reaction OF THE QUASI-AROMATIC complex WITH FORMALDEHYDE Ni
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Studies on the Displacement Reaction of Trialkylaluminum with Ethylene Catalyzed by Nitrogen Chelate Cobalt Complexes
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作者 Bin ZHOU Ren HE 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第2期135-137,共3页
The catalytic properties of a series of cobalt complexes containing bidenated nitrogen ligand for displacement reaction of trialkylaluminum with ethylene is reported. Effect of different reaction time, temperature an... The catalytic properties of a series of cobalt complexes containing bidenated nitrogen ligand for displacement reaction of trialkylaluminum with ethylene is reported. Effect of different reaction time, temperature and cobalt complexes containing different ligand on catalyst performance has been investigated. 展开更多
关键词 ETHYLENE displacement reaction trialkylaluminum cobalt complex.
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Relation between the complex Ginzburg-Landau equation and reaction-diffusion system
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作者 邵昕 任毅 欧阳颀 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第3期513-517,共5页
The complex Ginzburg-Landau equation (CGLE) has been used to describe the travelling wave behaviour in reaction-diffusion (RD) systems. We argue that this description is valid only when the RD system is close to t... The complex Ginzburg-Landau equation (CGLE) has been used to describe the travelling wave behaviour in reaction-diffusion (RD) systems. We argue that this description is valid only when the RD system is close to the Hopf bifurcation, and is not valid when a RD system is away from the onset. To test this, we study spirals and anti-spirals in the chlorite-iodide-malonic acid (CIMA) reaction and the corresponding OGLE. Numerical simulations confirm that the OGLE can only be applied to the CIMA reaction when it is very near the Hopf onset. 展开更多
关键词 complex Ginzburg-Landau equation reaction-diffusion system chlorite-iodide-malonic acid
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Effect of Complexants on Nano-La_2O_3 Prepared by Solid State Chemical Reaction
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作者 朱达川 胡盛东 +2 位作者 庄稼 杨定明 涂铭旌 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第S1期57-59,共3页
Precursors were prepared by solid state chemical reaction between LaCl_3 and C_2H_2O_4·2H_2O or NH_4HCO_3 at ambient temperature. Differential temperature analysis (DTA) and thermogravimetric analysis (TGA) were ... Precursors were prepared by solid state chemical reaction between LaCl_3 and C_2H_2O_4·2H_2O or NH_4HCO_3 at ambient temperature. Differential temperature analysis (DTA) and thermogravimetric analysis (TGA) were used to determine the decomposing temperature. Oxide (La_2O_3) was obtained by decomposing the precursor for about 2.5 h. X-ray diffraction (XRD), scanning electronic microscope (SEM) and ZETA potentiometer were respectively used to analyze the composition, morphology and size distribution of the products. The results show that La_2O_3 prepared by LaCl_3 and C_2H_2O_4·2H_2O is of ball-like shape and the diameter of particles (95%) is below 50 nm, while La_2O_3 prepared by LaCl_3 and NH_4HCO_3 is net-like. 展开更多
关键词 complexants nano-La_2O_3 solid state chemical reaction PRECURSOR rare earths
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Reaction of Bis(Methylcyclopentadienyl) Lanthanide Amido Complex with n-Hexyl isocyanate-Synthesis and Characterization of {(MeC_5H_4)_2YbOC(NPh_2)N(n-hexyl)}_2
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作者 郭华东 姚英明 +2 位作者 邓明宇 张勇 沈琪 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第6期653-656,共4页
Bis (methylcyclopentadienyl) lanthanide amido complex (MeCp) 2YbNPh2 (THF) reacted with n-hexyl isocyanate (n-nexylNCO) in 1:1 molar ratio to give {(MeC5H4)2Yb[OC(NPh2)N(n-hexyl)] }2(1). Complex 1 was... Bis (methylcyclopentadienyl) lanthanide amido complex (MeCp) 2YbNPh2 (THF) reacted with n-hexyl isocyanate (n-nexylNCO) in 1:1 molar ratio to give {(MeC5H4)2Yb[OC(NPh2)N(n-hexyl)] }2(1). Complex 1 was characterized by elemental analyses and X-ray diffraction. The title complex belongs to trigonal system and R-3 space group. Its unit cell parameters are a =2.9533(11) nm, b =2.9533(11) nm, c = 1.5873(6) nm, V= 11.9896(80) nm^3, Z =9, Dc= 1.562 mg·m^-3, μ = 3.536 mm^-1(Mo Kα), F(000) =5670, R =0.034, Rw =0.064. It is a dimeric structure with two symmetrical bridged oxygen atoms. Nitrogen atom is coordinated to the ytterbium atom to form a tricyclic backbone. The coordination number of ytterbium is 9. The whole molecule shows central symmetry. 展开更多
关键词 inorganic chemistry cyclopentadienyl lanthanide amido complex n-hexyl isocyanate insertion reaction crystal structure rare earths
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Comparative Studies between Chemical and Tribochemical Reactions of Some Metal Complexes Derived from N-(O-Hydoxyphenyl)-N'-phenylthiourea (L)
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作者 Sawsan Mohamed Al-Ashqar 《Open Journal of Inorganic Chemistry》 2016年第3期195-204,共11页
The reactions of N-(O-hydoxyphenyl)-N'-phenylthiourea (L) derived from with Cu<sup>+</sup>, Cu<sup>2+</sup>, Co<sup>2+</sup> and Co<sup>3+</sup> chloride and/or iodi... The reactions of N-(O-hydoxyphenyl)-N'-phenylthiourea (L) derived from with Cu<sup>+</sup>, Cu<sup>2+</sup>, Co<sup>2+</sup> and Co<sup>3+</sup> chloride and/or iodide afford new metal complexes. The isolated complexes were synthesized by two different techniques (chemical and tribochemical methods). Two complexes were synthesized by the direct chemical reactions of N-(O-hydoxyphenyl)-N'-phenylthiourea (L) with MCl<sub>2</sub>·XH<sub>2</sub>O (M = Co<sup>2+</sup> and Cu<sup>2+</sup>;X = 6 in case of Co<sup>2+</sup> and X = 2 in case of Cu<sup>2+</sup>) in absolute EtOH. The general formulae of the two complexes derived by the chemical method are [Cu(L)<sub>2</sub>(EtOH)<sub>2</sub>]Cl<sub>2</sub> and [Co(L)<sub>2</sub>Cl<sub>2</sub>]Cl. These complexes were used to synthesize another two complexes using tribochemical reaction by grinding the previous chloride complexes with excess KI in agate mortar in the solid state. The isolated complexes have the general formulae, [Cu(L)I·H<sub>2</sub>O]·1/2H<sub>2</sub>O and [Co(L)I<sub>3</sub>(Et- OH)]·3EtOH. The results indicate the substitution of the chloride by iodide ions during grinding and extraction of the complexes by solvents. The IR spectra of the complexes suggest that L acts in a bidentate manner towards the metal ions. Moreover, the results of electronic spectra and magnetic measurements for the chloride complexes suggest distorted-octahedral structure for Cu<sup>2+</sup> and low-spin octahedral structures around the Co<sup>II</sup> and Cu<sup>2+</sup> ions, respectively. On the other hand the data suggest that the iodide complexes have square-planer and low-spin for the Cu<sup>+</sup> and Co<sup>3+</sup> ions, respectively. The results of mass spectra confirm the formulae proposed for the isolated complexes. The mechanisms of reduction of Cu<sup>II</sup> and oxidation of Co<sup>II</sup> for the metal complexes were elucidated. 展开更多
关键词 Tribochemical reactions Derivatives of Thiourea complexes Cu2+ and Co3+ complexes
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Comparative Studies of New Complexes Synthesized by Chemical and Tribochemical Reactions Derived from Malonic Acid Dihydrazide (L;MAD) with Cu<sup>2+</sup>and Co<sup>2+</sup>Salts
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作者 Sawsan Mohamed Al-Ashqar 《Open Journal of Inorganic Chemistry》 2018年第1期28-42,共15页
The reaction of L (MAD) with Cu2+ and Co2+ chlorides affords new metal complexes. The isolated solid complexes were synthesized by two different techniques i.e., chemical and tribochemical methods. Four new complexes ... The reaction of L (MAD) with Cu2+ and Co2+ chlorides affords new metal complexes. The isolated solid complexes were synthesized by two different techniques i.e., chemical and tribochemical methods. Four new complexes were synthesized by direct chemical reactions of MCl2 (M = Co2+ and Cu2+) with MAD in absolute EtOH. The isolated solid complexes were used as starting compounds to synthesize another four new complexes using tribochemical technique by grinding the previous complexes in the solid state with excess KI in agate mortar. The results of the isolated complexes indicate the substitution of the chloride by iodide ions during grinding and extraction of the complexes by a mixture of solvents (EtOH + MeOH). Also, the results suggest that no reduction of Cu2+ or oxidation of Co2+ complexes is observed. The IR spectra of the complexes suggest that L acts in a bidentate manner. Moreover, the results of electronic spectra and magnetic measurements for the chloride and iodide complexes suggest distorted-octahedral and/or tetrahedral for Cu2+ and high-spin octahedral and/or tetrahedral structures around the Co2+ ion, respectively. 展开更多
关键词 Tribochemical reactions MAD complexES Spectral and Magnetic STUDIES Cu2+ and Co2+ complexES Green Chemistry
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