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硝基苯胺类非线性光学化合物的高压合成
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作者 邹新琢 井敏一 《有机化学》 SCIE CAS CSCD 北大核心 2002年第10期778-781,共4页
提出了用氯代硝基苯和胺的高压芳香族亲核取代反应一步合成硝基苯胺类非线性光学化合物的方法 .并筛选出一些具有较高二阶非线性光学活性的化合物 .
关键词 高压合成 硝基苯胺 线性光学化合物 氯代硝基苯 亲核取代反应
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金属间化合物(Mg,Zn)_(12)Ce与(Mg,Zn)_(11)Ce的研究
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作者 黄明丽 李洪晓 丁桦 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2015年第6期796-799,810,共5页
对300℃时Mg-Zn-Ce系富镁侧化合物的成分特征、结构和相平衡关系进行了研究.结果表明,Mg-Zn-Ce富镁角存在一个Mg12Ce的二元置换固溶体(Mg,Zn)12Ce,还存在一个三元线性化合物(Mg,Zn)11Ce(τ相).(Mg,Zn)12Ce中Zn的范围为0~7.3%(... 对300℃时Mg-Zn-Ce系富镁侧化合物的成分特征、结构和相平衡关系进行了研究.结果表明,Mg-Zn-Ce富镁角存在一个Mg12Ce的二元置换固溶体(Mg,Zn)12Ce,还存在一个三元线性化合物(Mg,Zn)11Ce(τ相).(Mg,Zn)12Ce中Zn的范围为0~7.3%(原子分数),其晶体结构为体心四方晶格.三元线性化合物τ相含Zn为8.5%~43.5%(原子分数),其晶体结构为C底心正交晶格.(Mg,Zn)12Ce和τ相均与α(Mg)存在稳定的两相平衡,且在Mg-Zn-Ce系富镁角还存在三相平衡Mg+(Mg,Zn)12Ce+τ. 展开更多
关键词 Mg-Zn-Ce系 二元固溶体 三元线性化合物 相平衡
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Mg-Zn-La系富Mg角固态相平衡的研究
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作者 李洪晓 黄明丽 +2 位作者 陈琴 任玉平 郝士明 《金属学报》 SCIE EI CAS CSCD 北大核心 2007年第7期749-752,共4页
利用SEM、XRD以及EPM对Mg-Zn-La系相图中富Mg角300℃的固态相平衡进行了研究.结果表明.在Mg-Zn-La系存在一个线性化合物(Mg,Zn)_(92)La_8(T相),而且在富Mg角存在一个由T相+α-Mg相组成的宽阔的两相区,以及α-Mg+MgZn(La)相+T相的三相区.
关键词 Mg-Zn-La系 相平衡 线性化合物
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Phase equilibria in the Mg-rich corner of the Mg-Zn-La system at 350°C 被引量:1
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作者 LI Hongxiao REN Yuping HUANG Mingli CHEN Qin HAO Shiming 《Rare Metals》 SCIE EI CAS CSCD 2006年第5期572-575,共4页
The phase equilibria in the Mg-rich comer of the Mg-Zn-La system at 350℃ have been investigated by scanning electron microscopy, X-ray diffraction, and electron probe microanalysis. It has been shown that the linear ... The phase equilibria in the Mg-rich comer of the Mg-Zn-La system at 350℃ have been investigated by scanning electron microscopy, X-ray diffraction, and electron probe microanalysis. It has been shown that the linear compound (Mg,Zn)17La2 existed in the Mg-Zn-La system at 350℃. The linear cornpound (so-called Tphase) was with the C-centred orthorhombic crystal structure induced by the solution of significant quantities of the third element. The three-phase region α(Mg) + MgZn(La) + T and the two-phase region composed of the α(Mg) and the linear-compound T phase existed in the Mg-rich comer of the Mg-Zn-La system at 350℃. 展开更多
关键词 Mg-Zn-La system phase diagram linear compound
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Free triiodothyronine level correlates with statin responsiveness in acute myocardial infarction 被引量:2
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作者 Wen-Yao WANG Kuo ZHANG +3 位作者 Wei ZHAO A. Martin Gerdes Giorgio Iervasi Yi-Da TANG 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2018年第4期290-297,共8页
Background Although thyroid hormone (TH) has important effects on lipid metabolism, the relationship between TH and statin responsiveness has never been investigated. We hypothesize that TH plays an important role i... Background Although thyroid hormone (TH) has important effects on lipid metabolism, the relationship between TH and statin responsiveness has never been investigated. We hypothesize that TH plays an important role in statin responsiveness in patients with acute myocardial infarction (AMI). Methods Consecutive 1091 hospitalized AMI patients in Fuwai hospital (Beijing, China) were enrolled into this current study. The study population was divided into three groups based on the intensity of statin treatment: low-intensity (n = 221), moderate-intensity (n = 712) and high-intensity (n = 158). Lipid levels were measured after statin therapy lasting for 10-14 days. The association between TH, lipid profile levels and achievement of low-density lipoprotein cholesterol (LDL-C) lowering goals was explored in patients with AMI on statin therapy. Results By general linear analysis, a significant linear trend between free triiodothyronine (FT3) and LDL-C level (linear coefficient r = -0.082, P = 0.001) and FT3 and total cholesterol (TC) level (r = -0.105, P = 0.031) was observed in the moderate-intensity statin group. A more apparent linear trend was detected in the high-intensity statin group (for LDL-C: r = -0.113, P = 0.005; for TC: r = -0.172, P = 0.029, respectively). However, no significant correlation was observed in the low-intensity statin group. Compared with the low-FT3 group (defined as FT3 〈 1.79 pg/mL), the OR (95% CI) for attaining a LDL-C 〈 3.0mmol/L was found to be 2.217 (1.001–4.839) in the higher FT3 group (〉 2.95 pg/mL). The OR (95% CI) for attaining the more intensive goal (LDL-C 〈 1.8mmol/L) was 2.836 (1.014–5.182). Conclusions Our study reveals that variation in FT3 levels is related to the cholesterol-lowering responsiveness of statins in AMI patients. These findings suggest that low FT3 may be a factor responsible for lack of LDL-C goal attainment and patients’ poor responsiveness to statin treatment. 展开更多
关键词 Acute myocardial infarction Free triiodothyronine HYPOTHYROID STATIN
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The Effective AC Response of Nonlinear Composites
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作者 WEIEn-Bo GUGuo-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第4期501-504,共4页
A perturbative approach is used to study the AC response of nonlinear composite media, which obey a current-field relation of the form with components having nonlinear response at finite frequencies. For a sinusoidal... A perturbative approach is used to study the AC response of nonlinear composite media, which obey a current-field relation of the form with components having nonlinear response at finite frequencies. For a sinusoidal applied field, we extend the local potential in terms of sinusoidal components at fundamental frequency and high-order harmonic frequencies to treat the nonlinear composites. For nonlinear composite media with a low concentrations of spherical inclusions, we give the formulae of the nonlinear effective AC susceptibility at the third harmonic frequency. 展开更多
关键词 nonlinear composite effective nonlinear susceptibility
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Microstructure and electrical properties of Lu_2O_3-doped ZnO-Bi_2O_3-based varistor ceramics 被引量:8
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作者 徐东 史小锋 +4 位作者 程晓农 杨娟 樊曰娥 袁宏明 施利毅 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第12期2303-2308,共6页
Lu2O3-doped ZnO-Bi2O3-based varistor ceramics samples were prepared by a conventional mixed oxide route and sintered at temperatures in the range of 900-1 000°C,and the microstructures of the varistor ceramics sa... Lu2O3-doped ZnO-Bi2O3-based varistor ceramics samples were prepared by a conventional mixed oxide route and sintered at temperatures in the range of 900-1 000°C,and the microstructures of the varistor ceramics samples were characterized by X-ray diffractometry(XRD)and scanning electron microscopy(SEM);at the same time,the electrical properties and V-I characteristics of the varistor ceramics samples were investigated by a DC parameter instrument for varistors.The results show that the ZnO-Bi2O3-based varistor ceramics with 0.3%Lu2O3(molar fraction)sintered at 950°C exhibit comparatively ideal comprehensive electrical properties.The XRD analysis of the samples shows the presence of ZnO,Bi-rich,spinel Zn7Sb2O12 and Lu2O3-based phases. 展开更多
关键词 ZnO-Bi2O3 ceramics VARISTOR rare earth electrical properties
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Synthesis,algal inhibition activities and QSAR studies of novel gramine compounds containing ester functional groups 被引量:2
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作者 李霞 于良民 +2 位作者 姜晓辉 夏树伟 赵海洲 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第2期309-316,共8页
2,5,6-Tribromo-l-methylgramine (TBG), isolated from bryozoan Zoobotryon pellucidum was shown to be very efficient in preventing recruitment of larval settlement. In order to improve the compatibility of TBG and its ... 2,5,6-Tribromo-l-methylgramine (TBG), isolated from bryozoan Zoobotryon pellucidum was shown to be very efficient in preventing recruitment of larval settlement. In order to improve the compatibility of TBG and its analogues with other ingredients in antifouling paints, structural modification of TBG was focused mainly on halogen substitution and N-substitution. Two halogen-substitute gramines and their derivatives which contain ester functional groups at N-position of gramines were synthesized. Algal inhibition activities of the synthesized compounds against algae Nitzschia cIosterium were evaluated and the Median Effective Concentration (EC50) range was 1.06-6.74 lag ml^-1. Compounds that had a long chain ester group exhibited extremely high antifouling activity. Quantitive Structure Activity Relationship (QSAR) studies with multiple linear regression analysis were applied to fred correlation between different calculated molecular descriptors and biological activity of the synthesized compounds. The results show that the toxicity (log (I/EC50)) is correlated well with the partition coefficient log P. Thus, these products have potential function as antifouling agents. 展开更多
关键词 gramine derivative SYNTHESIS algal inhibition activity QSAR
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Identification of variety of rice and determination of content of each rice in mixtures of two rices by nonlinear chemical analysis
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作者 CHEN Chun-nan XU Tian-shu +9 位作者 ZHONG Jun-hui WANG Zhi-pei LUO Xue-lei GUO Fang-qiu ZHANG Tai-ming DU Juan YANG Chun-hua ZHU Hong-qiu HUANG Jian DENG Fei-yue 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第2期251-258,共8页
Fingerprints of two varieties of rice and their mixtures were investigated by a nonlinear chemical reaction system consisting of rice components,sodium bromate,manganese sulfate,sulfuric acid and acetone.The variety o... Fingerprints of two varieties of rice and their mixtures were investigated by a nonlinear chemical reaction system consisting of rice components,sodium bromate,manganese sulfate,sulfuric acid and acetone.The variety of rice was identified by the visual characteristic of fingerprint and system similarity pattern recognition,and the content of each variety of rice in the mixture was determined by the quantitative information of fingerprint.The results show that nonlinear chemical analysis may be used to exactly identify the variety of pure rice and to accurately determine the content of each variety of rice in the mixture,indicating the method is simple and convenient. 展开更多
关键词 nonlinear chemical analysis binary mixture variety identification content determination RICE
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Porosity Estimation from Compressional Wave Velocity: A Study Based on Egyptian Carbonate Samples
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作者 Mohamed A. Kassab Andreas Weller 《Journal of Earth Science and Engineering》 2013年第5期314-321,共8页
The porosity of a rock is one of the most important reservoir properties. It controls the reservoir storage capacity. In other words, porosity quantifies the amount of fluids that the rock can store. Most of the world... The porosity of a rock is one of the most important reservoir properties. It controls the reservoir storage capacity. In other words, porosity quantifies the amount of fluids that the rock can store. Most of the world's giant fields produce hydrocarbons from carbonate reservoirs. Carbonate rocks contain more than 50% of the world's hydrocarbon reserves. Porosity and compressional wave velocity of 41 carbonate samples were determined under ambient conditions in laboratory. The samples were collected from seven shallow wells in west Tushka area, south Western Desert, Egypt. This paper evaluates the well known Wyllie and Raymer equations, an empirical linear equation, and a generalized model for porosity estimation from compressional wave velocity of saturated carbonate samples. Based on the comparison of the predicting identified to provide the most reliable porosity estimation. qualities, the Raymer equation and the empirical linear equation were 展开更多
关键词 Carbonate rocks POROSITY compressional wave velocity Wyllie equation Raymer equation.
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Artificial Neural Network Model of Hydrocarbon Migration and Accumulation
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作者 刘海滨 吴冲龙 《Journal of China University of Mining and Technology》 2002年第2期210-214,共5页
Based on the dynamic simulation of the 3 D structure the sedimentary modeling, the unit entity model has been adopted to transfer the heterogeneous complex passage system into limited simple homogeneous entity, and th... Based on the dynamic simulation of the 3 D structure the sedimentary modeling, the unit entity model has been adopted to transfer the heterogeneous complex passage system into limited simple homogeneous entity, and then the traditional dynamic simulation has been used to calculate the phase and the drive forces of the hydrocarbon , and the artificial neural network(ANN) technology has been applied to resolve such problems as the direction, velocity and quantity of the hydrocarbon migration among the unit entities. Through simulating of petroleum migration and accumulation in Zhu Ⅲ depression, the complex mechanism of hydrocarbon migration and accumulation has been opened out. 展开更多
关键词 hydrocarbon migration and accumulation nonlinear course ANN
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Estimation of surface tension of organic compounds using quantitative structure-property relationship 被引量:2
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作者 戴益民 刘又年 +3 位作者 李浔 曹忠 朱志平 杨道武 《Journal of Central South University》 SCIE EI CAS 2012年第1期93-100,共8页
A novel quantitative structure-property relationship (QSPR) model for estimating the solution surface tension of 92 organic compounds at 20℃ was developed based on newly introduced atom-type topological indices. Th... A novel quantitative structure-property relationship (QSPR) model for estimating the solution surface tension of 92 organic compounds at 20℃ was developed based on newly introduced atom-type topological indices. The data set contained non-polar and polar liquids, and saturated and unsaturated compounds. The regression analysis shows that excellent result is obtained with multiple linear regression. The predictive power of the proposed model was discussed using the leave-one-out (LOO) cross-validated (CV) method. The correlation coefficient (R) and the leave-one-out cross-validation correlation coefficient (Rcv) of multiple linear regression model are 0.991 4 and 0.991 3, respectively. The new model gives the average absolute relative deviation of 1.81% for 92 substances. The result demonstrates that novel topological indices based on the equilibrium electro-negativity of atom and the relative bond length are useful model parameters for QSPR analysis of compounds. 展开更多
关键词 surface tension quantitative structure-property relationship (QSPR) topological indice organic compound
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Direct tension and fracture resistance curves of ultra high performance marine composite materials
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作者 吴香国 韩相默 《Journal of Marine Science and Application》 2008年第3期218-225,共8页
Fracture behavior is one of the most important,yet still little understood properties of ultra-high performance cementitious composites(UHPCC),a new marine structural engineering material. Research on the fracture and... Fracture behavior is one of the most important,yet still little understood properties of ultra-high performance cementitious composites(UHPCC),a new marine structural engineering material. Research on the fracture and direct tension behavior of UHPCC was carried out.The constitution law of UHPCC was divided into three phases:pre-partial debonding,partial debonding,and pullout phases.A direct tension constitution law was constructed based on the proposed fiber reinforcing parameter as a function of fiber volume fraction,fiber diameter and length,and fiber bonding strength.With the definition of linear crack shape,the energy release rate of UHPCC was derived and the R-curve equation was calculated from this.Loading tests of UHPCC using a three-point bending beam with an initial notch were carried out.The predictions from the proposed R-curve were in good agreement with the test results, indicating that the proposed R-curve accurately describes the fracture resistance of UHPCC.Introduction of a fiber reinforcement parameter bridges the fracture property R-curve and micro-composites’ mechanics parameters together.This has laid the foundation for further research into fracture properties based on micro-mechanics.The proposed tension constitution law and R-curve can be references for future UHPCC fracture evaluation. 展开更多
关键词 ultra high performance cementitious composites FRACTURE resistance curve direct tension
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Ni-Co-Sn三元系相平衡的实验研究
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作者 刘兴军 邓育灵 +5 位作者 张锦彬 杨木金 杨水源 韩佳甲 卢勇 王翠萍 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2020年第5期1539-1545,共7页
采用电子探针显微分析和X-ray衍射分析方法研究了Ni-Co-Sn三元体系在700和1000℃时的相平衡。在这两个温度截面中均未发现三元化合物。βCo3Sn2相和Ni3Sn2(h)相形成了一个贯穿连续固溶体相。Ni-Sn侧包含Ni3Sn(l)、Ni3Sn(h)和Ni3Sn43个... 采用电子探针显微分析和X-ray衍射分析方法研究了Ni-Co-Sn三元体系在700和1000℃时的相平衡。在这两个温度截面中均未发现三元化合物。βCo3Sn2相和Ni3Sn2(h)相形成了一个贯穿连续固溶体相。Ni-Sn侧包含Ni3Sn(l)、Ni3Sn(h)和Ni3Sn43个化合物相,它们中Sn的固溶度是有很大区别的。700℃时,Co在Ni3Sn(l)和Ni3Sn4中的最大固溶度分别约为6.9 at%和25.6 at%,在1000℃时,Co在Ni3Sn(h)中的最大固溶度约为15.5 at%。在700和1000℃下,Ni-Co侧的(αCo,Ni)相为一个贯穿连续固溶体相,并且Sn在(αCo,Ni)相中的固溶度为1 at%~10.5 at%。Ni在线性化合物CoSn相中的溶解度约为15.9 at%。 展开更多
关键词 Ni-Co-Sn三元系 相平衡 线性化合物
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Emission and drying kinetics of paper mill sludge during contact drying process 被引量:1
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作者 Wen-yi DENG Xiao-dong LI +4 位作者 Jian-hua YAN Fei WANG Sheng-yong LU Yong CHI Ke-fa CEN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第11期1670-1677,共8页
The emission and contact drying kinetics of the paper mill sludge (PMS) were studied through experiments carried out in a paddle dryer. To get a better understanding of its drying mechanism, a penetration model develo... The emission and contact drying kinetics of the paper mill sludge (PMS) were studied through experiments carried out in a paddle dryer. To get a better understanding of its drying mechanism, a penetration model developed by Tsotsas and Schlünder (1986) was used to simulate the drying kinetics of the PMS. The result indicated that this kinetics could be divided into three phases: pasty, lumpy and granular phases, and could be successfully simulated by the penetration model as the related sludge parameters were integrated into the model. The emission rate curves of the volatile compounds (VCs) were interrelated to the drying rate curve of the PMS, especially for volatile fatty acids (VFAs) and ammonia in this study. 展开更多
关键词 Contact drying EMISSION Paper mill sludge (PMS) Paddle dryer
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Amavadin induced PTP opening not through the promotion of ROS generation in rat kidney mitochondria
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作者 霍辰伊 刘会雪 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2014年第12期830-836,共7页
Amavadin is a natural vanadium compound that accumulates to high level in poisonous Amanita mushrooms. Recently, amavadin was found to have potential therapeutic effect in cancer treatment. However, its toxicity and t... Amavadin is a natural vanadium compound that accumulates to high level in poisonous Amanita mushrooms. Recently, amavadin was found to have potential therapeutic effect in cancer treatment. However, its toxicity and the possible mechanism of actions are still not clear. In this study, we investigated the toxic effects of amavadin on rat kidney mitochondria and the possible mechanism. We found that amavadin induced significantly permeability transition pore (PTP) opening in the mitochondria. Amavadin y inhibited the generation of reactive oxygen species (ROS) in succinate buffer, and at high concentration of 200 gM it increased the ROS generation in malate buffer. With the addition of rotenone, the ROS generation in malate buffer was strongly enhanced than that induced by amavadin alone, but remained unchanged in succinate buffer. Results from the present study suggest that amavadin act upon electron transport chain downstream of rotenone, and the ubiquinone binding site in complex I is the most possible binding site. 展开更多
关键词 Amavadin Vanadium compound MITOCHONDRIA Reactive oxygen species Permeability transition pore
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Theoretical study on magneto-structural correlation of trinuclear copper (II) complex with the hydroxo bridge and bidentate syn-syn carboxylate group
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作者 QI Zhongnan WU Jian +2 位作者 LIU Chengbu WANG Ruoxi SUN Youmin 《Chinese Science Bulletin》 SCIE EI CAS 2006年第12期1421-1425,共5页
The theoretical study on magneto- structural correlation in linear trinuclear Cu (II) com- plex bridged by hydroxo group and bidentate formato group has been performed using the broken symme- try approach with the fra... The theoretical study on magneto- structural correlation in linear trinuclear Cu (II) com- plex bridged by hydroxo group and bidentate formato group has been performed using the broken symme- try approach with the framework of density functional theory (DFT-BS). The magnetic coupling constant for the model complex is 70.97 cm?1, comparable with the experimentally measured J value (77 cm?1). The calculated results show that the magnetic coupling interaction firstly slightly increases with the changes of the coordination environment around the terminal Cu atoms from a distorted square pyramid to a trigonal bi-pyramid, and decreases subsequently. In the course of changes, the sign of J value shifts from positive to negative. The magnetic coupling interac- tion is sensitive to coordination environment of the terminal Cu. The calculated results also reveal that the ferromagnetic coupling arises from the counter- complementarity of the hydroxo and formato bridges. Molecular orbital analysis validates the conclusion. 展开更多
关键词 线性三核铜化合物 磁电结构关系 破缺对称性逼近 磁耦合常数 羧酸盐
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Highly linear polyethylenes using the2-(1-(2,4-dibenzhydrylnaphthylimino)ethyl)-6-(1-(arylimino)ethyl)-pyridylcobalt chlorides: synthesis, characterization and ethylene polymerization 被引量:2
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作者 Erlin Yue Yanning Zeng +3 位作者 Wenjuan Zhang Yang Sun Xiao-Ping Cao Wen-Hua Sun 《Science China Chemistry》 SCIE EI CAS CSCD 2016年第10期1291-1300,共10页
The series of 2-(1-(2,4-dibenzhydrylnaphthylimino)ethyl)-6-(1-(arylimino)ethyl)pyridine derivatives and their cobalt chlorides (Col-Co5) were synthesized and fully characterized. The representative complexes... The series of 2-(1-(2,4-dibenzhydrylnaphthylimino)ethyl)-6-(1-(arylimino)ethyl)pyridine derivatives and their cobalt chlorides (Col-Co5) were synthesized and fully characterized. The representative complexes Co2 and Co3 were confirmed by single crystal X-ray diffraction analyses, indicating pseudo-square-pyramidal geometry around the cobalt centre. All cobalt complexes, activated with either methylaluminoxane (MAO) or modified methylaluminoxane (MMAO), exhibited high activities towards ethylene polymerization, and produced polyethylenes with high molecular weight and highly linear feature as well as unimodal distribution. 展开更多
关键词 cobalt complexes ethylene polymerization highly linear polyethylene unimodal distribution
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