期刊文献+
共找到23篇文章
< 1 2 >
每页显示 20 50 100
International study of the Complex Stress Reaction Syndrome:Implications for transdiagnostic clinical practice
1
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
下载PDF
A novel profile modification HPF-Co gel satisfied with fractured low permeability reservoirs in high temperature and high salinity
2
作者 Ya-Kai Li Ji-Rui Hou +6 位作者 Wei-Peng Wu Ming Qu Tuo Liang Wei-Xin Zhong Yu-Chen Wen Hai-Tong Sun Yi-Nuo Pan 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期683-693,共11页
Conformance control and water plugging are a widely used EOR method in mature oilfields.However,majority of conformance control and water plugging agents are unavoidable dehydrated situation in high-temperature and hi... Conformance control and water plugging are a widely used EOR method in mature oilfields.However,majority of conformance control and water plugging agents are unavoidable dehydrated situation in high-temperature and high-salinity low permeability reservoirs.Consequently,a novel conformance control system HPF-Co gel,based on high-temperature stabilizer(CoCl_(2)·H_(2)O,CCH)is developed.The HPF-Co bulk gel has better performances with high temperature(120℃)and high salinity(1×10^(5)mg/L).According to Sydansk coding system,the gel strength of HPF-Co with CCH is increased to code G.The dehydration rate of HPF-Co gel is 32.0%after aging for 150 d at 120℃,showing excellent thermal stability.The rheological properties of HPF gel and HPF-Co gel are also studied.The results show that the storage modulus(G′)of HPF-Co gel is always greater than that of HPF gel.The effect of CCH on the microstructure of the gel is studied.The results show that the HPF-Co gel with CCH has a denser gel network,and the diameter of the three-dimensional network skeleton is 1.5-3.5μm.After 90 d of aging,HPF-Co gel still has a good three-dimensional structure.Infrared spectroscopy results show that CCH forms coordination bonds with N and O atoms in the gel amide group,which can suppress the vibration of cross-linked sites and improve the stability at high temperature.Fractured core plugging test determines the optimized polymer gel injection strategy and injection velocity with HPF-Co bulk gel system,plugging rate exceeding 98%.Moreover,the results of subsequent waterflooding recovery can be improved by 17%. 展开更多
关键词 Low permeability reservoir High-temperature resistant gel Complexation reaction Polymer gel injection strategy Plugging rate Enhanced oil recovery
下载PDF
Effects of Oleanolic Acid on the Immune Complex Allergic Reaction and Inflammation
3
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
下载PDF
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
4
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
下载PDF
Molecular-Based Simulation of Feedstock Properties for Complex Reaction System
5
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
下载PDF
SYTHESE AND REACTIONS OF HETEROBINUCLEAR COMPLEXES [PhCl_2SnM(Cl)(CO)_3(CH_3CN)_2] (M = Mo, W)
6
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
下载PDF
COMPLEX REACTIONS OF ETHYL-GLUCOSIDES SYNTHESIS OVER ION EXCHANGE RESIN
7
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
下载PDF
THE STUDY OF THE REACTION OF THE QUASI-AROMATIC COMPLEX [Ni(PnAO)-6H]^(?)WITH FORMALDEHYDE: KINETICS AND MECHANISM
8
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
下载PDF
STUDIES ON THE CHROMOPHORIC REACTIONS OF MIXED POLYNUCLEAR COMPLEXES OF RARE EARTH-ARSENAZO Ⅲ-COPPERO-PHENANTHROLINE
9
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
下载PDF
Optically Active β-Hydroxy Carbonyl Compound from a Mukaiyama Reaction Catalyzed by M-Salen Complex
10
《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
下载PDF
Preparation of Platinum(II) Complexes with 1-β-D-Ribofuranosyl-1,2,4-triazole-3-carboxamide and its Deoxy-analogue 被引量:7
11
作者 Wen PEI Kobe JOZE 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第6期559-562,共4页
The platinum (II) complexes of the [Pt (N4,N7-Ribavirin) (DMSO) Cl], [Pt (N4,N7-De-oxyribavirin) (DMSO) Cl] were obtained by the reactions of cis-[Pt (DMSO)2 Cl2] and K[Pt (DMSO) Cl3] with 1-??-D-ribofuranosyl-1,2,4-t... The platinum (II) complexes of the [Pt (N4,N7-Ribavirin) (DMSO) Cl], [Pt (N4,N7-De-oxyribavirin) (DMSO) Cl] were obtained by the reactions of cis-[Pt (DMSO)2 Cl2] and K[Pt (DMSO) Cl3] with 1-??-D-ribofuranosyl-1,2,4-triazole-3-carboxamide (Ribavirin) and its deoxy-analogue (deoxyribavirin). The preparation of 1-(2'-deoxy-?-D-ribofuranosyl) -1,2,4-triazole-3-carboxamide was also performed through a four-step procedure, protection of 3', 5'-dihydroxyl group of Ribavirin with 1,3-dichloro-1,1,3,3-tetraisopropyldisiloxane (TPDS-Cl), phenoxythio-carbonylation of the 2'-hydroxyl group of 3', 5'-O-TPDS-Ribavirin with phenoxythiocarbonyl-chloride (PTC-Cl), reduction of 2′-O-phenoxythiocarbonyl ester of 3', 5'-O-TPDS-Ribavirin with tri-n-butyltin hydride and AIBN, deprotection of 3', 5'-O-TPDS-Ribavirin with tetrabutylammon-ium fluoride in THF. 展开更多
关键词 Platinum(II) complexes ribavirin and deoxyribavirin nucleobase platination complexation reaction antitumor agents
下载PDF
Optimization of selective copper extraction from chalcopyrite concentrate in presence of ammonium persulfate and ammonium hydroxide 被引量:1
12
作者 Mehmet Deniz Turan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2019年第8期946-952,共7页
The dissolution of copper and iron from chalcopyrite concentrate in the presence of ammonium persulfate(APS)and ammonium hydroxide was investigated under atmospheric leaching conditions.Experiments were designed by ce... The dissolution of copper and iron from chalcopyrite concentrate in the presence of ammonium persulfate(APS)and ammonium hydroxide was investigated under atmospheric leaching conditions.Experiments were designed by central composite design(CCD).Under the optimum leaching conditions((NH4)2S2O8 concentration=328 g/L;NH4OH addition=16vol%;leaching temperature=321 K(48℃);leaching time=120 min;liquid-to-solid ratio=16;stirring speed=400 r/min),selective leaching was achieved.98.14%of the copper was leached,whereas iron did not pass into the solution.X-ray diffraction analysis of the leaching residue showed that iron compounds were predominant.Given the leaching results,the fact that the leaching process does not include uneconomical leaching stages such as extended milling/mechanical activation or high pressures/temperatures,and the low copper dissolution conditions,the attained selective leaching yield may be remarkable. 展开更多
关键词 LEACHING complex reaction SELECTIVITY COPPER CHALCOPYRITE
下载PDF
Syntheses,Structures and Photoluminescent Properties of Cd(Ⅱ)Polymeric Complexes Based on 5-Aminoisophthalic Acid and Bipyridine Co-ligands 被引量:1
13
作者 余程 许文涛 +2 位作者 熊伟 周有福 黄得财 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第1期143-152,共10页
Two novel complexes, namely {[Cd(AIP)(4,4'-bpy)]·1.3DMF}n(1) and [Cd(AIP)(2,2'- bpy)]n(2), have been synthesized through solvothermal reaction(H2AIP = 5-aminoisophthalic acid, 2,2'-bpy = 2,2'-bip... Two novel complexes, namely {[Cd(AIP)(4,4'-bpy)]·1.3DMF}n(1) and [Cd(AIP)(2,2'- bpy)]n(2), have been synthesized through solvothermal reaction(H2AIP = 5-aminoisophthalic acid, 2,2'-bpy = 2,2'-bipyridine, 4,4'-bpy = 4,4'-bipyridine, and DMF = N,N'-dimethylformamide) and structurally determined by single-crystal X-ray diffraction. Complex 1 shows a three-dimensional(3D) layer-pillar framework with rectangular channels, while complex 2 displays a two-dimensional(2D) wave net architecture. Furthermore, 1 and 2 were characterized by elemental analysis, infrared spectra(IR), thermal gravimetric analyses(TGA) and fluorescence measurements. The luminescent properties of 1 dispersed in various organic solvents have been investigated systematically, demonstrating high selectivity for acetone via the fluorescence quenching effect. 展开更多
关键词 Cd(Ⅱ) polymeric complexes solvothermal reaction luminescent properties
下载PDF
Adiabatic correction for the esterification of acetic anhydride by methanol via accurate kinetics
14
作者 Ze Dong Liping Chen +2 位作者 Yingying Ma Haoliang Peng Wanghua Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第9期1954-1959,共6页
In the field of adiabatic correction for complex reactions,a simple one-stage kinetic model was used to estimate the real reaction kinetics.However,this assumption simplified the real process,inevitably generated inac... In the field of adiabatic correction for complex reactions,a simple one-stage kinetic model was used to estimate the real reaction kinetics.However,this assumption simplified the real process,inevitably generated inaccurate or even unsafe results.Therefore,it was necessary to find a new correction method for complex reactions.In this work,esterification of acetic anhydride by methanol was chosen as an object reaction of study.The reaction was studied under different conditions by Reaction Calorimeter(RC1).Then,Thermal Safety Software(TSS)was used to establish the kinetic model and estimate the parameters,where,activation energies for three stages were67.09,81.02,73.77 kJ?mol^(-1)respectively,and corresponding frequency factors in logarithmic form were 16.05,19.59,15.72 s^(-1).In addition,two adiabatic tests were performed by Vent Sizing Package2(VSP2).For accurate correction of VSP2 tests,a new correction method based on Enhanced Fisher method was proposed.Combined with kinetics,adiabatic correction of esterification reaction was achieved.Through this research,accurate kinetic parameters for a three-step kinetic model of the esterification reaction were acquired.Furthermore,the correlation coefficients between simulated curves and corrected curves were 0.976 and 0.968,which proved the accuracy of proposed new adiabatic correction method.Based on this new method,conservative corrected results were able to be acquired and be applied in safety assessment. 展开更多
关键词 Adiabatic correction KINETICS New method Complex reaction ESTERIFICATION Model reaction
下载PDF
Monodentate phosphorus-coordinated palladium(Ⅱ)complexes as new catalyst for Mizoroki-Heck reaction of aryl halides with electron-deficient olefins 被引量:2
15
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
原文传递
Study on the cocolouration effect in the β-complex formation reactions of rare earths with p-chloro-chlorophosphonazo (CPApC)
16
作者 XU, Zhong-Jun (HSU, Chung-Gin) ZHANG, Lan PAN, Jiao-Mai Department of Chemistry, East China Normal University, Shanghai 200062 《Chinese Journal of Chemistry》 SCIE CAS CSCD 1992年第5期424-429,共0页
Terbium- and yttrium-group rare earths form β-complexes with CPApC in acidic medium. The sensitivities for determination of these rare earths by this reaction depend on their ionic radii. Cerium- or terbium-group rar... Terbium- and yttrium-group rare earths form β-complexes with CPApC in acidic medium. The sensitivities for determination of these rare earths by this reaction depend on their ionic radii. Cerium- or terbium-group rare earth in the presence of yttrium-group element produces the cocolouration effect which remarkably sensitizes the reaction. Yb-CPApC-Eu complex has a molar composition of 1:4:2 and gives a molar absorptivity of 2. 02 ×10~5 L·mol^(-1)·cm^(-1) at 746 nm for Eu. It is found that the closer the lengths of ionic radii of the rare earths are, the greater will be the cocolouration effect. 展开更多
关键词 CPApC Study on the cocolouration effect in the complex formation reactions of rare earths with p-chloro-chlorophosphonazo
全文增补中
Linear free energy relationships between reaction rate constants and equilibrium constants of complex compounds——III. Kinetics and mechanisms of ternary complex formation between (5-X-1, 10-phenanthroline)copper(II) and threonine 被引量:1
17
作者 CHEN Rong-Ti (Y.T.Chen) +1 位作者 ZHANG Qi-Yan LI Yue-Jin 《Acta Chimica Sinica English Edition》 SCIE CAS CSCD 1989年第4期342-348,共1页
The kinetics of ternary complex formation involving Cu(5-X-1, 10-phen) and threonine (CuAL, A=5-X-1, 10-phen; L=threonine or represented by O-N; X=NO_2, Cl, H, CH_3) has been studied by temperature-jump and stopped-fl... The kinetics of ternary complex formation involving Cu(5-X-1, 10-phen) and threonine (CuAL, A=5-X-1, 10-phen; L=threonine or represented by O-N; X=NO_2, Cl, H, CH_3) has been studied by temperature-jump and stopped-flow methods. The formation rate constants, k_f(M^(-1).s^(-1)), for the complexation reaction, CuA + LCuAL, are as follows; X=NO_2, 8.68×10~8; X=Cl, 7.13×10~8; X=H, 6.12×10~8; X=CH_3, 5.42×10~8. The rate constants for zwitterion attack are nil within experimental error. It has been found that a linear free energy relationship exists between the stability(logK_(CuAL)^(CuA) of the complexes CuAL and log kf as follows: IogK_(CuAL)^(CuA)=0.13 + 0.83 logk_f, r=0.99. It suggested that the formation rate governed the stability of the ternary complexes. The rates of formation of the ternary complexes increased with decreasing electron-donating property of the substituents. A linear relationship was found to exist as expressed by the following equation: log(k_f^R/k_F^O) = 0.097σ, r=0.96. A mechanism involves a rapid equilibrium between CuA and L followed by a slow ring closure of L. 展开更多
关键词 rate Kinetics and mechanisms of ternary complex formation between and threonine phenanthroline)copper II Linear free energy relationships between reaction rate constants and equilibrium constants of complex compounds X-1 III free
全文增补中
Nitrosyl Complexes 6.Reactions of Na[Fe(CO)_3NO]with Cp~*M(CO)_3Cl(Cp~*=η~5-CH_3C_5H_4,M=Mo or W):Crystal structures of Cp~*M(CO)_2NO and Cp~*M(μ_3-NH)(μ_2-NO)(μ_2-CO)Fe_2(CO)_6
18
作者 SUN,Wen-Hua YANG,Shi-Yan YIN,Yuan-Qi WANG,Han-Qing State Key Laboratory of Oxo Synthesis and Selective Oxidation,Lanzhou Institute of Chemical Physics,Chinese Academy of Sciences,Lanzhou 730000YU,Kai-Bei Chengdu Center of Analysis and Measurement,Chinese Academy of Sciences,Chengdu 610041 《Chinese Journal of Chemistry》 SCIE CAS CSCD 1993年第2期151-158,共8页
Sodium nitrosylcarbonyliron reacts with methylcyclopentadienylcarbonylmetal(Mo orW)chloride in CHOH/THF at room temperature to give CpMo(CO)NO(1a)(Cp=η-CHCH)or CpW(CO)NO(1b),[CpMo(CO)](2a)or[CpW(CO)]... Sodium nitrosylcarbonyliron reacts with methylcyclopentadienylcarbonylmetal(Mo orW)chloride in CHOH/THF at room temperature to give CpMo(CO)NO(1a)(Cp=η-CHCH)or CpW(CO)NO(1b),[CpMo(CO)](2a)or[CpW(CO)](2b),and CpMo(μ3-NH)(μ2-NO)-(μ2-CO)Fe(CO)(3a)or CpW(μ3-NH)(μ2-NO)(μ2-CO)Fe(CO)(3b),respectively.Complexes1a,1b,3a and 3b were analyzed by IR,NMR,MS and elemental analyses,and the crystalstructures of 1b,3a and 3b were determined by X-ray diffraction method.The new clusters 3aand 3b have μ3-NH ligands which were formed by redaction of NO in the synthetic reactions. 展开更多
关键词 Nitrosyl Complexes 6.reactions of Na[Fe with Cp CP Crystal structures of Cp and Cp Mo NO NA NH Cl
全文增补中
Planarization mechanism of alkaline copper CMP slurry based on chemical mechanical kinetics 被引量:6
19
作者 王胜利 尹康达 +2 位作者 李湘 岳红维 刘云岭 《Journal of Semiconductors》 EI CAS CSCD 2013年第8期197-200,共4页
The planarization mechanism of alkaline copper slurry is studied in the chemical mechanical polishing (CMP) process from the perspective of chemical mechanical kinetics.Different from the international dominant acid... The planarization mechanism of alkaline copper slurry is studied in the chemical mechanical polishing (CMP) process from the perspective of chemical mechanical kinetics.Different from the international dominant acidic copper slurry,the copper slurry used in this research adopted the way of alkaline technology based on complexation. According to the passivation property of copper in alkaline conditions,the protection of copper film at the concave position on a copper pattern wafer surface can be achieved without the corrosion inhibitors such as benzotriazole(BTA),by which the problems caused by BTA can be avoided.Through the experiments and theories research,the chemical mechanical kinetics theory of copper removal in alkaline CMP conditions was proposed. Based on the chemical mechanical kinetics theory,the planarization mechanism of alkaline copper slurry was established. In alkaline CMP conditions,the complexation reaction between chelating agent and copper ions needs to break through the reaction barrier.The kinetic energy at the concave position should be lower than the complexation reaction barrier,which is the key to achieve planarization. 展开更多
关键词 chemical mechanical kinetics alkaline copper slurry planarization mechanism complexation reaction barrier
原文传递
Affinity Solvents for Intensified Organics Extraction: Development Challenges and Prospects 被引量:1
20
作者 André B. de Haan 《Tsinghua Science and Technology》 SCIE EI CAS 2006年第2期171-180,共10页
In most organics extraction processes, the commonly used solvents employ solely physical interactions. Therefore, for the recovery and purification of products from complex mixtures, the selectivity and/or capacity of... In most organics extraction processes, the commonly used solvents employ solely physical interactions. Therefore, for the recovery and purification of products from complex mixtures, the selectivity and/or capacity of classical solvents towards the desired solutes is usually insufficient, enforcing the need for complex and thus expensive separation schemes. Significant simplification and cost-reduction can be achieved when affinity solvents would be available that are able to recognize the solutes of interest by their molecular structure. The main development challenges to establish such affinity solvents are: Selection and incorporation of molecular recognition and complexation capabilities; Evaluation of extraction capabilities; Efficient re- covery and recycling of the affinity solvents; Implementation in industrial extraction equipment. This paper presents how these development challenges are addressed at the University of Twente, going all the way from affinity solvent design and synthesis, via high throughput screening and characterization up to pilot plant evaluation. Essential in the successful development of affinity solvents are structural cooperations with molecular chemists and custom synthesis companies for their design and synthesis. The various aspects are illustrated by several examples where newly developed environmentally benign affinity solvents appeared able to create major breakthroughs. The applications addressed involve oxygenates, sugars, and pharmaceutical ingredients, such as optical isomers and biomolecules. 展开更多
关键词 affinity solvent organics extraction molecular recognition complexation reaction
原文传递
上一页 1 2 下一页 到第
使用帮助 返回顶部