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Synthesis and Properties of Nonatungstotricobaltosilicate Isomers

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Chemical Research in Chinese Universities 1993年第4期9卷 357-363页

作者： LIU Jing-fu, zhao ben-liang, WANG Fu-quan and FANG Qun-xin (Department of Chemistry Northeast Normal University, Changchun, 130024)

Introduction Recently substituted-type of heteropolyanions has received much attention from the point of view of their catalysis. Hill, Finke, Neumann reported respectively that transition metal mono-substituted heteropolyanions PW;M, P;W;M and SiW;Ru have an ability to catalyze the epoxidation of olefin. We discovered that trisubstituted Keggin heteropolyanions have this property too. This paper describes the synthesis, properties of α- and β-[SiW;O;Co;（H;O）;];and its catalysis for the epoxidation of olefin by PhIO.

关键词： Nonatungstotricobaltosilicate Trisubstituted heteropolyanion Epoxidation of olefin

Etherification of Methanol with Propylene Oxide Catalyzed by Heteropolyacids

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Chemical Research in Chinese Universities 1994年第3期10卷 250-251页

作者： zhao ben-liang XU Gui-ying LI Bin and LIU Jing-fu (Department of Chemistry, Northeast Normal University , Changchun, 130024)

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ＥｔｈｅｒｉｆｉｃａｔｉｏｎｏｆＭｅｔｈａｎｏｌｗｉｔｈＰｒｏｐｙｌｅｎｅＯｘｉｄｅＣａｔａｌｙｚｅｄｂｙＨｅｔｅｒｏｐｏｌｙａｃｉｄｓＺＨＡＯＢｅｎ－ｌｉａｎｇ；ＸＵＧｕｉ－ｙｉｎｇ；ＬＩＢｉｎａｎｄＬＩＵＪｉｎｇ－ｆｕ（ＤｅｐａｒｔｍｅｎｔｏｆＣ...

关键词： Heteropolyacid catalysts Etherification Heteropoly blue

The chlorine evolution reaction promoted by organocatalysts with amide functional groups

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Science China Chemistry 2024年第3期67卷 749-750页

作者： Lan zhao liang-Nian He State Key Laboratory and Institute of Elemento-Organic Chemistry College of ChemistryNankai UniversityTianjin 300071China

Since the nineteenth century, the chlor-alkali process entails the electrochemical oxidation of sodium chloride solutions to Cl_(2) by the chlorine evolution reaction(CER) and the simultaneous production of sodium hyd... 详细信息

关键词： chlorine hydroxide promoted

An efficient strategy enabling solution processable thermally activated delayed fluorescence emitter with high horizontal dipole orientation

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Chinese Journal of Structural Chemistry 2024年第6期43卷 4-5页

作者： Zheng zhao ben Zhong Tang School of Science and Engineering Shenzhen Institute of Aggregate Science and TechnologyThe Chinese University of Hong KongShenzhen(CUHK-Shenzhen)Guangdong518172China

Organic light-emitting diodes(OLEDs)based on highly efficient aggregate emitters present a significant breakthrough in realizing low-cost displays and solid-state lighting,thus drawing considerable research interest i... 详细信息

关键词： emitter breakthrough dipole

An Anisotropic Biomimetic Lemongrass Flexible Piezoelectric Actuator-Inhibitory Regression

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Journal of Bionic Engineering 2024年第4期21卷 1817-1829页

作者： Tianwei liang Yunhong liang Jiru Wang Hu Huang Zhi Xu Hongwei zhao Key Laboratory of CNC Equipment Reliability Ministry of EducationJilin UniversityChangchun130022China School of Mechanical and Aerospace Engineering Jilin UniversityChangchun130022China Institute of Structured and Architected Materials Liaoning Academy of MaterialsShenyang110167China The Key Laboratory of Bionic Engineering Ministry of EducationJilin UniversityChangchun130025China

At present,the existing piezoelectric stick-slip actuators have an inherent back-slip problem,which greatly limits the development and application of stick-slip *** order to inhibit the regression phenomenon,a new bionic lemongrass stickslip actuator was prepared by using polymer PDMS to replicate natural biological *** surface microstructure of the grass was copied by PDMS,and the PDMS film was *** rigid and flexible bionic friction pair was further prepared,and the flexible anisotropic PDMS stick slip actuator was *** was found that the anisotropic friction characteristics of the surface microstructure of the grass inhibited the anti-sliding motion,and the elastic potential energy of the PDMS film improved the output characteristics of the *** adjusting the input voltage to control the contact between the drive foot and the rotor,the rigid and flexible hybrid drive can be realized and the backsliding phenomenon can be *** actuator is compact,lightweight and can achieve high speed and high resolution output without preloading force,which has important application value in the field of fast and accurate positioning with load limitation.

关键词： Piezoelectric actuator Bionic surface Friction Surface friction Flexible film

Remarkable enhancement of gas selectivity on organosilica hybrid membranes using urea-modulated metal-organic framework nanoparticles

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Frontiers of Chemical Science and Engineering 2024年第2期18卷 83-92页

作者： Yayun zhao Dechuan zhao Chunlong Kong Yichao Lin Xuezhen Wang liang Chen Key Laboratory of Advanced Fuel Cells and Electrolyzers Technology of Zhejiang Province Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China University of Chinese Academy of Sciences Beijing 100049China Collaboration Innovation Center for Tissue Repair Material Engineering Technology China West Normal UniversityNanchong 637009China

Metal-organic framework/organosilica hybrid membranes on tubular ceramic substrates have shown great potential for the implementation of membrane technology in practical gas separation projects due to their higher permeance compared to commercial ***,the selectivities of the reported membranes are ***,we have incorporated urea-modulated metal-organic frameworks into organosilica membranes to greatly enhance its separation *** urea-modulated metal-organic frameworks exhibit less-defined edges of crystallographic facets and high defect *** can be well-dispersed in the organosilica layer,which substantially suppresses the interfacial defects between metal-organic frameworks and organosilica,which is beneficial for improving the selectivity of membranes for gas *** results have shown that the enhanced ideal selectivity of H_(2)/CH_(4) was 165 and that of CO_(2)/CH_(4) was 43,with H_(2) permeance of about 1.25×10^(−6) mol·m^(−2)·s^(−1)·Pa^(−1) and CO_(2) permeance of 3.27×10^(−7) mol·m^(−2)·s^(−1)·Pa^(−1) at 0.2 MPa and 25℃.In conclusion,the high level of hybrid membranes can be used to separate H_(2)(or CO_(2))from the binary gas mixture H_(2)/CH_(4)(or CO_(2)/CH_(4)),which is important for gas separation in practical ***,the simple and feasible modulation of metal-organic framework is a promising strategy to tune different metal-organic frameworks for membranes according to the actual demands.

关键词： ZIF-8 nanocrystals urea organosilica hybrid membrane enhanced separation performance

Probabilistic-Ellipsoid Hybrid Reliability Multi-Material Topology Optimization Method Based on Stress Constraint

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 757-792页

作者： Zibin Mao Qinghai zhao liang Zhang College of Mechanical and Electrical Engineering Qingdao UniversityQingdao266071China National Engineering Research Center for Intelligent Electrical Vehicle Power System Qingdao UniversityQingdao266071China

This paper proposes a multi-material topology optimization method based on the hybrid reliability of the probability-ellipsoid model with stress constraint for the stochastic uncertainty and epistemic uncertainty of mechanical loads in optimization *** probabilistic model is combined with the ellipsoidal model to describe the uncertainty of mechanical *** topology optimization formula is combined with the ordered solid isotropic material with penalization(ordered-SIMP)multi-material interpolation *** stresses of all elements are integrated into a global stress measurement that approximates the maximum stress using the normalized p-norm ***,the sequential optimization and reliability assessment(SORA)is applied to transform the original uncertainty optimization problem into an equivalent deterministic topology optimization(DTO)*** response surface and sparse grid technique are combined with SORA to get accurate information on the most probable failure point(MPP).In each cycle,the equivalent topology optimization formula is updated according to the MPP information obtained in the previous *** adjoint variable method is used for deriving the sensitivity of the stress constraint and the moving asymptote method(MMA)is used to update design ***,the validity and feasibility of the method are verified by the numerical example of L-shape beam design,T-shape structure design,steering knuckle,and 3D T-shaped beam.

关键词： Stress constraint probabilistic-ellipsoid hybrid topology optimization reliability analysis multi-material design

Hybrid stacking ensemble algorithm and simulated annealing optimization for stability evaluation of underground entry-type excavations

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Underground Space 2024年第4期17卷 25-44页

作者： Leilei Liu Guoyan zhao Weizhang liang Zheng Jian School of Resources and Safety Engineering Central South UniversityChangsha 410083China

The stability of underground entry-type excavations(UETEs)is of paramount importance for ensuring the safety of mining *** more engineering cases are accumulated,machine learning(ML)has demonstrated great potential for the stability evaluation of *** this study,a hybrid stacking ensemble method aggregating support vector machine(SVM),k-nearest neighbor(KNN),decision tree(DT),random forest(RF),multilayer perceptron neural network(MLPNN)and extreme gradient boosting(XGBoost)algorithms was proposed to assess the stability of ***,a total of 399 historical cases with two indicators were collected from seven ***,to pursue better evaluation performance,the hyperparameters of base learners(SVM,KNN,DT,RF,MLPNN and XGBoost)and meta learner(MLPNN)were tuned by combining a five-fold cross validation(CV)and simulated annealing(SA)*** on the optimal hyperparameters configuration,the stacking ensemble models were constructed using the training set(75%of the data).Finally,the performance of the proposed approach was evaluated by two global metrics(accuracy and Cohen’s Kappa)and three within-class metrics(macro average of the precision,recall and F1-score)on the test set(25%of the data).In addition,the evaluation results were compared with six base learners optimized by *** hybrid stacking ensemble algorithm achieved better comprehensive performance with the accuracy,Kappa coefficient,macro average of the precision,recall and F1-score were 0.92,0.851,0.885,0.88 and 0.883,*** rock mass rating(RMR)had the most important influence on evaluation ***,the critical span graph(CSG)was updated based on the proposed model,representing a significant improvement compared with the previous *** study can provide valuable guidance for stability analysis and risk management of ***,it is necessary to consider more indicators and collect more extensive and balanced dataset to validate the model in futur

关键词： Underground entry-type excavations(UETEs) Hybrid stacking ensemble Machine learning Simulated annealing Critical span graph Base and meta learners

Systematic study of the synthesis of heavy and superheavy nuclei in 48Ca-induced fusion-evaporation reactions

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Nuclear Science and Techniques 2024年第7期35卷 157-172页

作者： Shi-Hao Zhu Tian-liang zhao Xiao-Jun Bao Department of Physics Collaborative Innovation Center for Quantum EffectsKey Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of EducationHunan Normal UniversityChangsha410081China School of Nuclear Science and Technology Lanzhou UniversityLanzhou730000China School of Physics Xi’an Jiaotong UniversityXi’an710049China

We systematically studied the evaporation residue cross sections of ^(48)Ca-induced reactions on lanthanide and actinide target nuclei under the Dinuclear System(DNS)model framework to check the reliability and applicability of the *** produce new proton-rich Fl and Lv isotopes through hot fusion reactions in the superheavy element region with Z≥104,we utilized the reactions ^(48)Ca+^(236,238,239) Pu and ^(48)Ca+^(242,243,244,250) ***,owing to the detection limit of available equipment(0.1 pb),only 283Fl and 287−289Lv,which have the maximum evaporation residue cross section values of 0.149,0.130,9.522,and 0.309 pb,respectively,can be ***,to produce neutron-deficient isotopes of actinides near the proton drip line with Z=93−100,we attempted to generate the new isotopes(224−227Pu,228−232,237Cm)using the reactions ^(48)Ca+180,182,183 W and ^(48)Ca+^(184,186,187,192) *** maximum evaporation residue cross section values are 0.07,0.06,0.26,and 0.30 nb for the former set of reactions,and 1.96 pb,5.73 pb,12.16 pb,19.39 pb,54.79 pb,and 6.45 nb for the latter,*** results are expected to provide new information for the future synthesis of unknown neutron-deficient isotopes.

关键词： Dinuclear system(DNS)model Evaporation residue cross section Neutron-deficient isotopes