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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
The kinetics of complex reaction systems were studied on molecular level with the combined method of Monte Carlo simulation and Structural Oriented Lumping by focusing on deep catalytic cracking (DCC) process, the m... The kinetics of complex reaction systems were studied on molecular level with the combined method of Monte Carlo simulation and Structural Oriented Lumping by focusing on deep catalytic cracking (DCC) process, the model parameters were optimized by means of routine analytic data of a DCC unit. A model was established to transform the feedstock of the complex reaction systems such as DCC to 1000-10000 pseudo-molecules with the Monte Carlo simulation and every molecule was expressed by 19 attributes. The results of model simulation showed that these pseudo-molecules reflected the characteristics of feedstock very well and their average properties gave a good agreement with the plant data. 展开更多
关键词 complex reaction system molecular scale kinetic model Monte Carlo simulation deep catalyticcracking
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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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Thermal kinetic analysis of a complex process from a solid-state reaction by deconvolution procedure from a new calculation method and related thermodynamic functions of Mn_(0.90)Co_(0.05)Mg_(0.05)HPO_4?3H_2O 被引量:1
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作者 Chuchai SRONSRI Banjong BOONCHOM 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第9期1887-1902,共16页
Three individual peaks of thermal solid-state reaction processes of the synthesized Mn0.90Co0.05Mg0.05HPO4?3H2O were observed corresponding to dehydration I,dehydration II and polycondensation processes.An alternative... Three individual peaks of thermal solid-state reaction processes of the synthesized Mn0.90Co0.05Mg0.05HPO4?3H2O were observed corresponding to dehydration I,dehydration II and polycondensation processes.An alternative method for the calculation of the extent of conversion was proposed from the peak area of the individual DTG peak after applying the best fitting deconvolution function(Frazer–Suzuki function).An iterative integral isoconversional equation was used to compute the values of the apparent activation energy Eαand they were found to be 65.87,78.16 and 119.32 kJ/mol for three peaks,respectively.Each individual peak was guaranteed to be a single-step kinetic system with its unique kinetic parameters.The reaction mechanism functions were selected by the comparison between experimental and model plots.The results show that the first,second and final individual peaks were two-dimensional diffusion of spherical symmetry(D2),three-dimensional diffusion of spherical symmetry(D3)and contracting cylinder(cylindrical symmetry,R2)mechanisms.Pre-exponential factor values of 3.91×106,1.35×107 and 2.15×107 s?1 were calculated from the Eαvalues and reaction mechanisms.The corresponded standard thermodynamic functions of the transition-state(activated)complexes were determined and found to agree well with the experimental data. 展开更多
关键词 solid-state reaction calculation method complex reaction Frazer–Suzuki function experimental and model plots
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Effects of Oleanolic Acid on the Immune Complex Allergic Reaction and Inflammation
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作者 周重楚 孙晓波 +3 位作者 刘威 高洪波 师海波 苗艳波 《Journal of Chinese Pharmaceutical Sciences》 CAS 1993年第1期69-79,共11页
When oleanolic acid (OA) was administered ig before and after sensitization on d 1 to d 5 and d 11 to d 17,it had no apparent effect on Arthus reaction.When it was administered at 48,24 and 1 h before challenge,howeve... When oleanolic acid (OA) was administered ig before and after sensitization on d 1 to d 5 and d 11 to d 17,it had no apparent effect on Arthus reaction.When it was administered at 48,24 and 1 h before challenge,however,Arthus reaction was significantly inhibited.OA showed markedly suppressive effects on reversible passive Arthus reaction and leukocyte migratory response.It could significantly stabilize erythrocyte membrane,inhibit the swelling of the rat's hind paw induced by in- jecting mycostatin,reduce the acid phosphatase content in the inflammatory exudate,suppress the syn- thesis or release of PGE,histamine,LTB4 and kinin,and the phlogistic action of PGE_2,histamine,5- HT and kinin.In addition,it could decrease the content of malonyldialdehyde (MDA) in hepatic tissue of alcohol-intoxicated mice,and increase the activity of catalase (CAT) in hepatic tissue of mice.OA had no apparent effect on the activity of super-oxide dismutase (SOD) in rat serum,on the content of immune complex in serum of rat with Arthus reaction,on the phagocytosis of monocytc-macrophage system,on the clearance of enzyme-containing immune complex by macrophage,or on the activity of total complement. 展开更多
关键词 Oleanolic acid Immune complex allergic reaction Anti-immune complex allergic reaction INFLAMMATION ANTI-INFLAMMATION
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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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Monodentate phosphorus-coordinated palladium(Ⅱ)complexes as new catalyst for Mizoroki-Heck reaction of aryl halides with electron-deficient olefins 被引量:2
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作者 Fang Zhao Li Xin +1 位作者 Yingying Zhang Xuefeng Jia 《Chinese Chemical Letters》 SCIE CAS CSCD 2018年第3期493-496,共4页
Four novel palladium((Ⅱ)) complexes coordinated by phosphorus atoms from both 3,5-disubstituted-1H- 1,2,4-diazaphospholes in monodentate fashion were developed as efficient catalyst for the Mizoroki- Heck reactio... Four novel palladium((Ⅱ)) complexes coordinated by phosphorus atoms from both 3,5-disubstituted-1H- 1,2,4-diazaphospholes in monodentate fashion were developed as efficient catalyst for the Mizoroki- Heck reaction of aryl halides with electron-deficient olefins. The coupling reaction of awl halide bearig different functional groups with olefin derivatives took place and the corresponding products were isolated in good to excellent yields under optimal conditions. The procedure exhibits good functional group tolerance and wide substrate scope. This Mizoroki-Heck reaction was further achieved using Pd(OAc)2 and 3,5-di-isopropyl-1H-1,2,4-diazaphospholes as combined catalyst, which provide the convenient and alternative method in organic synthesis 展开更多
关键词 Palladium(Ⅱ) complexes Monodentate phosphine ligands Mizoroki-Heck reaction Aryl halides Olefins
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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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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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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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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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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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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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