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Integrative Zoology 2013年第3期8卷 315-323页

作者： Tonglei YU xin lu Department of Zoology College of Life SciencesWuhan UniversityWuhanChina

Age and growth rate are critical parameters determining the body size of adult anurans,which grow ***,evaluating their relative importance and selective pressures acting on them may help to explain variation in body size of anurans across geographical *** on the data on body size and skeletochronological age of 4 Asiatic toad(Bufo gargarizans)populations that are widely separated in latitude,the present study showed that toads at the northern extremity of the range were the oldest,on average,and grew relatively fast,toads at the southern end of the range were relatively old but grew fastest,whereas mid-latitude toads were intermediate in both *** results indicated that relative contributions of age and growth rate to body size differed among *** a life history perspective,greater age attained by toads at higher latitudes should result from delayed maturation,and faster growth from an adaptive response to strong seasonal time constraints;in contrast,selective pressures on the 2 parameters at lower latitudes might be associated,respectively,with low adult death rates and longer favorable growing seasons.

关键词： age body size Bufo gargarizans geographical variation growth rate

Hydrolysis Process of the Anticancer Agents Novel Non-classical trans-Platinum(Ⅱ) with Aliphatic Amines

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Chinese Journal of Structural Chemistry 2007年第8期26卷 962-972页

作者： YUAN Qing-hui ZHOU Li-xin Department of Chemistry Jinan University Guangzhou Guangdong 510632 China

The hydrolysis process of the anticancer agents novel non-classical transplatinum（ Ⅱ ） with aliphatic amines and the influence of solvent models therein have been studied by using hybrid density functional theory （B3LYP）. In this study, the stepwise hydrolysis, trans[PtCl2（Am）（isopropylamine）] ＋ 2H2O → trans-[Pt（Am）（isopropylamine）（OH2）2]^2＋＋ 2Cl^-, was explored. Implicit solvent effects were incorporated through polarized continuum models. The stationary points on the potential energy surfaces for the first and second hydrolysis steps,proceeding via a general SN2 pathway, were fully optimized and characterized. It was found that the first hydrolysis reaction is easier than the second one and the hydrolysis of trans- [PtCl2-（isopropylamine）2] is the easiest in our studying systems. The result can assist in under- tanding the hydrolysis mechanism of trans-[PtCl2（Am）（isopropylamine）] and designing novel Pt-based anticancer drugs.

关键词： hydrolysis DFT non-classical trans-platinum aliphatic amines transition state

Polybenzoxazine/organosilicon composites with low dielectric constant and dielectric loss

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Chinese Journal of Chemical Engineering 2023年第12期64卷 241-249页

作者： Manlin Yuan xin lu Xiaoyun Ma Hao Lin Angui lu Liyan Shao Zhong xin State Key Laboratory of Chemical Engineering School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China

The evolution of electronic communication technology raises higher requirements for low dielectric constant(low-k)*** this,a benzoxazine functional organosilicon(HP-aptes)with dense Si—O—Si crosslinking networks and large sterically hindered tert-butyl groups was prepared by the sol–gel ***,a series of polybenzoxazine composites(PPHP)were prepared from intrinsically low dielectric constant bis-functional benzoxazine monomer(P-aptmds)and *** double crosslinking networks of polybenzoxazine and organosilicon further increased the crosslinking density and decreased the dipole density of composites,which endowed the composites with enhanced low-k *** the content of HP-aptes is 30%(mass),the crosslinking density was 2.05×10^(-3)mol·cm^(-3),while that of PP-aptmds was 3.31×10^(-3)mol·cm^(-3).In addition,the dielectric constant and dielectric loss of PPHP composite at 1 MHz could reach 2.61 and 0.0056,respectively.

关键词： Polybenzoxazine Organosilicon Composite Dielectric constant

Three-dimensional Pyrenyl Graphdiyne Supported Pd Nanoparticle as an Efficient and Easily Recyclable Catalyst for Reduction of 4-Nitrophenol

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Chemical Research in Chinese Universities 2021年第6期37卷 1296-1300页

作者： RONG xin lu Xiuli lu Tongbu Institute for New Energy Materials& Low Carbon TechnologiesSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin300384P.R.China

The fabrication of highly active and easily recyclable Pd-based catalyst is meaningful for their practical ***,a Pd-based dip-catalyst(Pd@Pyr-GDY)is fabricated on graphdiyne(Pyr-GDY)grown on copper foam,and applied in the reduction of ***,the as-formed Pd@Pyr-GDY shows good catalytic performance toward the reduction of 4-nitrophenol(4-NP)to 4-aminophenol(4-AP)by NaBH4 with a rate constant k value of 3.84 min^(−1),which is 12-fold higher than that of the commercial Pd/*** importantly,Pd@Pyr-GDY could be easily and rapidly recovery from the reaction medium and no distinct inactivation was found after six cycles of the *** work presents an easy way to design an efficient and easily recyclable Pd-based catalyst for practical use.

关键词： Pd-based catalyst Dip-catalyst Reduction of 4-nitrophenol Recycling

Environmental boundary and formation mechanism of different types of H2S corrosion products on pipeline steel

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International Journal of Minerals,Metallurgy and Materials 2017年第4期24卷 401-409页

作者： Lei Zhang hui-xin Li Feng-xian Shi Jian-wei Yang Li-hua Hu Min-xu lu Institute for Advanced Materials and Technology University of Science and Technology Beijing Beijing 100083 China Aircraft Engine Corporation of China Shanghai Commercial Aircraft Engine Manufacturing Co. Ltd. Shanghai 201306 China Shougang Research Institute of Technology Beijing 100043 China China National Offshore Oil Corporation Research Institute Beijing 100027 China

To establish an adequate thermodynamic model for the mechanism of formation of hydrogen sulfide (H2S) corrosion products, theoretical and experimental studies were combined in this work. The corrosion products of API X60 pipeline steel formed under different H2S corrosion conditions were analyzed by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction. A thermodynamic model was developed to clarify the environmental boundaries for the formation and transformation of different products. Presumably, a dividing line with a negative slope existed between mackinawite and pyrrhotite. Using experimental data presented in this study combined with previously published results, we validated the model to predict the formation of mackinawite and pyrrhotite on the basis of the laws of thermodynamics. The established relationship is expected to support the investigation of the H2S corrosion mechanism in the oil and gas industry. © 2017, University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg.

关键词： Energy dispersive spectroscopy Forecasting Gas industry Iron ores Pipelines Scanning electron microscopy Steel corrosion Steel pipe Thermodynamic properties Thermodynamics X ray diffraction X ray spectroscopy

Passivity breakdown of 13Cr stainless steel under high chloride and CO_2 environment

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International Journal of Minerals,Metallurgy and Materials 2019年第3期26卷 329-336页

作者： hui-xin Li Da-peng Li Lei Zhang Ya-wen Wang Xiu-yun Wang Min-xu lu Institute for Advanced Materials and Technology University of Science and Technology Beijing Safetech Research Institute (Beijing) Co. Ltd. CRRC Beijing Locomotive Co. Ltd.

Herein, the effect of high chloride ion(Cl^-) concentration on the corrosion behavior and passive film breakdown of 13Cr martensitic stainless steel under CO_2 environment was demonstrated. The Cl^- concentration was varied from 30 to 150 g/L and cyclic potentiodynamic polarization was conducted to investigate the influence of the Cl^- concentration on the corrosion potential(E_(corr)), passive breakdown potential(E_(pit)), and repassivation potential(E_(rep)). The results of the polarization curves revealed that 13Cr stainless steel is susceptible to pitting under high Cl^- concentration. The passive breakdown potential and repassivation potential decreased with the increase of Cl-concentration. The semiconducting behavior of the passive film was investigated by Mott-Schottky analysis and the point defect model(PDM). It was observed that the iron cation vacancies and oxygen vacancies were continuously generated by autocatalytic reactions and the higher Cl^- concentration resulted in higher vacancies in the passive film. Once the excess vacancies condensed at the metal/film interface, the passive film became locally detached from the metal, which led to the breakdown of the passive film.

关键词： 13Cr stainless steel electrochemical characterization pitting corrosion high chloride concentration passive film breakdown

New Approach to Cluster Synchronization in Complex Dynamical Networks

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Communications in Theoretical Physics 2009年第3期51卷 485-489页

作者： lu xin-Biao QIN Bu-Zhi lu xin-Yu Department of Automation Hohai University Nanjing 210098 China Department of Automation Nanjing College of Chemical Technology Nanjing 210048 China Shandong Metallurgical Research Institute Jinan 250014 China

In this paper, a distributed control strategy is proposed to make a complex dynamical network achieve cluster synchronization, which means that nodes in the same group achieve the same synchronization state, while nodes in different groups achieve different synchronization states. The local and global stability of the cluster synchronization state are analyzed. Moreover, simulation results verify the effectiveness of the new approach.

关键词： cluster synchronization complex network distributed control strategy

Flight behavior of the sycamore lace bug, Corythucha ciliata, in relation to temperature, age, and sex

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Journal of Integrative Agriculture 2019年第10期18卷 2330-2337页

作者： lu Shao-hui WEI Mei-cai YUAN Guo-jun CUI Jian-xin GONG Dong-feng Laboratory of Insect Systematics and Evolutionary Biology Central South University of Forestry and TechnologyChangsha 410000P.R.China Henan Academy of Forestry Zhengzhou 450000P.R.China Henan Institute of Science and Technology Xinxiang 453000P.R.China

The flight capacity of different ages and sexes of the sycamore lace bug, Corythucha ciliata, was studied at different temperatures using a flight mill system. The results of regression analysis showed a significant effect of temperature on flight distance (P=0.0082). Temperature did not influence flight duration (P=0.212) or flight speed (P=0.175). The mean flight distance (1 024 m) and mean flight duration were the greatest at 25.2°C. The age of C. ciliata had a significant influence on flight distance (P=0.0005), flight duration (P=0.0005) and flight speed (P=0.026). The 12-d-old adult had the greatest flight distance (887 m), duration (3 875 s) and speed (0.22 m s^–1). Flight distances and flight duration of females were significantly longer than that of males. However, the male had significantly greater flight speed than the female. The insect appears to be capable of long distance flights. The understanding of the optimal age and temperature for the flight of this insect through this study provides a foundation for better management of the insect in China.

关键词： Corythucha ciliata flight capacity tethered flight temperature age and sex

Theoretical study on 2s2p^6np Rydberg states of Cu^(19+)ion

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Chinese Physics B 2012年第1期21卷 153-157页

作者： Zhang Zhen-Rong Cheng xin-lu Liu Zi-Jiang Yang Jian-hui Li hui-Fang Institute of Atomic and Molecular Physics Sichuan UniversityChengdu 610065China Department of Physics Lanzhou City UniversityLanzhou 730070 China

We report on the calculations of transition wavelengths and weighted oscillator strengths for 2s22p^6 2s2p^6np （4 〈 n 〈 20） electric dipole （El） transitions of Cu^19＋ ion. The flexible atomic code （FAC） has been adopted for the calculations. Comparisons are made with the experimental data available, showing that the present results for 4 〈 n 〈 6 are more accurate than the previous calculated values. Furthermore, combining the quantum defect theory （QDT） with the transition energies of 2s^22p^62s2p^6np, the quantum defects for 2s2p^6np Rydberg series of Cu^19＋ ion are determined. In addition, the energies of any highly excited states （n 〉 20） for this series can be reliably predicted using the QDT and the given quantum defects. The ionization energies for Cu^19＋ and Cu^20＋ ions are also calculated and they excellently accord with previous experimental and calculated values.

关键词： Cu^19+ion transition wavelength quantum defect quantum defect theory

Feature selection of BOF steelmaking process data by using an improved grey wolf optimizer

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Journal of Iron and Steel Research International 2022年第8期29卷 1205-1223页

作者： Zong-xin Chen hui Liu Long Qi Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming 650500YunnanChina Yunnan Key Laboratory of Artificial Intelligence Kunming University of Science and TechnologyKunming 650500YunnanChina

Basic oxygen furnace(BOF)steelmaking end-point control using soft measurement models has essential value for economy and ***,the high-dimensional and redundant data of the BOF collected by the sensors will hinder the performance of *** traditional feature selection results based on meta-heuristic algorithms cannot meet the stability of actual industrial *** order to eliminate the negative impact of feature selection application in the BOF steelmaking,an improved grey wolf optimizer(IGWO)for feature selection was proposed,and it was applied to the BOF data ***,the proposed algorithm preset the size of the feature subset based on the new encoding scheme,rather than the traditional uncertain number ***,opposition-based learning was used to initialize the grey wolf population so that the initial population was closer to the potential optimal *** addition,a novel population update method retained the features closely related to the best three grey wolves and probabilistically updated irrelevant features through measurement or random *** methods were used to search feature subsets to maximize search capability and stability of algorithm on BOF steelmaking ***,the proposed algorithm was compared with other feature selection algorithms on the BOF data *** results show that the proposed IGWO can stably select the feature subsets that are conductive to the end-point regression accuracy control of BOF temperature and carbon content,which can improve the performance of the BOF steelmaking.

关键词： Basic oxygen furnace Feature selection Grey wolf optimization Regression Opposition-based learning