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Polybinaphthyls of (R)-3,3′-Diiodo-2,2′-binaphtho-20-crown-6 with p-Divinylbenzene via Heck Cross-coupling Reaction

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Chemical Research in Chinese Universities 2003年第2期19卷 235-237页

作者： LIU Tian dong CHENG Yi xiang yang xiao liang Nanjing University School of Chemistry and Chemical EngineeringNanjing 210093China

The present paper deals with the polymerization of ( R ) 3,3′ diiodo 2,2′ binaphtho 20 crown 6 with \{ p divinylbenzene\} under Heck coupling reaction condition. Both the monomers and the polymer were analyzed by NMR, FTIR, UV, CD, fluorescent spectroscopy, polarimetry, GPC and elemental analysis. The polymer can emit a strong blue fluorescence and is expected to have the potential application in the polarized blue light emitting sensors. The chiral conjugated polymer exhibits a strong Cotton effect in its Circular Dichroism(CD ) spectrum, indicating the high rigidity of the polymer backbone.

关键词： (R)-BINOL Chiral conjugated polymer Heck cross-coupling reaction

Characteristics of an Explosive Cyclone over Northeast China Revealed by Satellite Water Vapor Imagery

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Journal of Tropical Meteorology 2022年第3期28卷 261-272页

作者： yang xiao-liang YAO Xiu-ping yang Yue yang Min CHEN Bi-ying Hebei Meteorological Observatory Shijiazhuang 050021 China Hebei Laboratory for Meteorological and Ecoenvironment Shijiazhuang 050021 China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081 China China Meteorological Administration Training Centre Beijing 100081 China Shijiazhuang Meteorological Bureau Shijiazhuang 050081 China Hebei Provincial Meteorological Administrative&Technical Service Center Shijiazhuang 050021 China

In this paper,an explosive cyclone(EC)that occurred over Northeast China in the spring of 2016 is studied by using 6.7μm FY satellite water vapor(WV)imagery and NCEP(1°×1°)reanalysis ***,the evolutions of the upper-level jet stream(ULJ),the vertical motions,and the potential vorticity(PV)are analyzed in *** show that different shapes of the WV image dark zones could reflect different stages of the *** the pre-explosion stage,a small dark zone and an S-shaped baroclinic leaf cloud can be found on the WV *** the dark zone expands and the leaf cloud grows into a comma-shaped cloud at the explosively developing *** the post-explosion stage,the dark zone brightens,and the spiral cloud *** whole process can be well described by the WV *** dynamic dry band associated with the sinking motion and the ULJ can develop into the dry intrusion later,which is an important signal in forecasting the EC and should be paid attention to when analyzing the WV ***,the mechanism is also analyzed in detail in this *** usually occurs in the left-exit region of the 200-h Pa jet and the region ahead of the 500-h Pa trough where there is significant positive vorticity advection(PVA).When the EC moves onto the sea surface,the decreased friction would favour the development of the *** upper-level PVA,the strong convergence at low level,and the divergence at high levels can maintain the strong ***,the high PV zone from the upper levels extends downward,approaching the ***,they keep the cyclone deepening continuously.

关键词： satellite water vapor imagery explosive cyclone dry intrusion physical quantity configuration

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微生物制剂对鲫鱼肠道微生物的影响

饲料研究 2024年第3期47卷 58-62页

作者：刘军吴海冰许洲程超李艳华褚旭东胡佳杨小亮绵阳市农业科学研究院四川绵阳621000 江油市农业农村局四川绵阳621700

试验旨在研究微生物制剂对鲫鱼生长和肠道微生物菌群的影响。选择大小均匀的鲫鱼300尾,随机分为5组,每组3个重复,每个重复20尾鱼。A组饲喂含乳酸菌制剂的饲料,B组饲喂含丁酸梭菌制剂的饲料,C组饲喂含乳酸菌+丁酸梭菌混合制剂的饲料,D组... 详细信息

试验旨在研究微生物制剂对鲫鱼生长和肠道微生物菌群的影响。选择大小均匀的鲫鱼300尾,随机分为5组,每组3个重复,每个重复20尾鱼。A组饲喂含乳酸菌制剂的饲料,B组饲喂含丁酸梭菌制剂的饲料,C组饲喂含乳酸菌+丁酸梭菌混合制剂的饲料,D组饲喂含乳酸菌+丁酸梭菌混合制剂+3 mg/g的纳米硒的饲料,对照组(CK组)饲喂基础饲料。试验期28 d。结果显示,A组、B组、D组鲫鱼的增重率高于CK组(P<0.05),A组鲫鱼的肥满度和饲料系数高于CK组(P<0.05)。D组鲫鱼肝胰脏超氧化物歧化酶(SOD)活性高于CK组(P<0.05),B组鲫鱼肝胰脏溶菌酶(LZM)活性高于CK组(P<0.05)。A组鲫鱼肠道内梭杆菌(Fusobactria)丰度明显升高,B组的鲫鱼肠道内拟杆菌丰度明显升高。研究表明,饲料中添加乳酸菌、丁酸梭菌以及纳米硒促进了鲫鱼的生长,改变了鲫鱼肠道微生物的群落结构,抑制了有害菌的繁殖。

关键词：微生物制剂鲫鱼生长性能肠道微生物

Revisiting the island of hexadecapoledeformation nuclei in the A≈150 mass region:focusing on the model application to nuclear shapes and masses

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Communications in Theoretical Physics 2024年第2期76卷 74-88页

作者： xiao-yang Wei Hua-Lei Wang Zhen-Zhen Zhang Min-liang Liu School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China Key Laboratory of High Precision Nuclear Spectroscopy Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

Based on the potential-energy-surface calculation,the impact of different deformation degrees of freedom on a single-particle structure and binding energies in nuclei around^(152)Nd,located on one of the hexadecapole-deformation islands,is analyzed in a multi-dimensional deformation *** energy maps,curves and tables are presented to indicate nuclear *** calculated equilibrium deformations and binding energies with different potential parameters are compared with experimental data and other *** is found that the inclusion of the hexadecapole deformations,especially the axial one,can improve the theoretical description of both nuclear shapes and *** addition,our calculated potential-energy curve shows that a critical deformation-point,β_(2)≈0.4,exists—the triaxial(hexadecapole)deformation effect can be neglectable but the hexadecapole(triaxial)one plays an important role before(after)such a critical point.

关键词： hexadecapole deformation binding energy potential-energy-surface calculation nuclear property

Decentralized Optimal Control and Stabilization of Interconnected Systems With Asymmetric Information

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 698-707页

作者： Na Wang xiao liang Hongdan Li xiao Lu the College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266000China the School of Automation and Electrical Engineering Linyi UniversityLinyi 276000China the College of Energy Storage Technology Shandong University of Science and TechnologyQingdao 266000China

The paper addresses the decentralized optimal control and stabilization problems for interconnected systems subject to asymmetric *** with previous work,a closed-loop optimal solution to the control problem and sufficient and necessary conditions for the stabilization problem of the interconnected systems are given for the first *** main challenge lies in three aspects:Firstly,the asymmetric information results in coupling between control and estimation and failure of the separation ***,two extra unknown variables are generated by asymmetric information(different information filtration)when solving forward-backward stochastic difference ***,the existence of additive noise makes the study of mean-square boundedness an *** adopted technique is proving and assuming the linear form of controllers and establishing the equivalence between the two systems with and without additive noise.A dual-motor parallel drive system is presented to demonstrate the validity of the proposed algorithm.

关键词： Asymmetric information decentralized control forwardbackward stochastic difference equations interconnected system stalibization

Progress in processing of porous titanium:a review

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Rare Metals 2024年第5期43卷 1932-1955页

作者： xiao-Li yang Xian-Feng Du Zhi-Lin Xu Zhong-Shuai liang Li-Long Xiong Engineering Research Center of Energy Storage Materials and Devices Ministry of EducationSchool of ChemistryXi'an Jiaotong UniversityXi'an 710049China

As a novel structural and functional material,porous titanium and its alloys have been widely used in the aerospace,marine engineering and biomedical fields due to their high corrosion resistance,low density,good biocompatibility and excellent mechanical ***,in this paper,a comprehensive review of powder metallurgy(PM)(including additive manufacturing(AM)processes)for fabricating porous titanium is firstly covered in terms of their working principles,capabilities,shortcomings and ***,the influencing factors of various methods on final pore structure of porous Ti are ***,a summary of the chemical methods(CM)to obtain the porous Ti is also provided,such as dealloying method and reduction ***,the tendency and direction of preparation technology as well as application of porous titanium were prospected.

关键词： Porous titanium Powder metallurgy Chemical method Pore structure Processing process

A new approach to the synthesis of α-chlorocycloalkanones

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Chinese Chemical Letters 2007年第12期18卷 1476-1478页

作者： Xing Hai Li Xin Ling yang xiao Mei liang Zhen Peng Kai Yun Ling Fu Heng Chen Dao Quan Wang Department of Applied Chemistry China Agricultural University Beijing 100094 China

α-Chlorocycloalkanones （IV） were synthesized from cycloalkanones via potassium ot-oxocycloalkylsulfonates （Ⅱ）. A two-step mechanism was proposed to explain the formation of IV from Ⅱ.

关键词： α-Chlorocycloalkanones Synthesis Potassium α-oxocycloalkylsulfonates

Study on Effectiveness of Solitary-Wave-Like Form Based on Overtopping Data from Irregular Wave Tests

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China Ocean Engineering 2024年第4期38卷 701-710页

作者： LI xiao-liang Huang Gui-biao School of Naval Architecture&Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

The previous study conducted by Li(2022)demonstrates that the Goda graph can be adequately represented by a solitary-wave-like form across the entire range of relative water depth,with the exception of the extremely shallow ***,it remains uncertain whether this form is equally effective when applied to test data generated by irregular waves,as the Goda graph was initially developed based on overtopping data from regular wave ***,it is unclear whether this form is suitable for formulating overtopping discharge at composite vertical *** order to address these questions,a 2D overtopping experiment was conducted,incorporating both simple and composite types of vertical walls,with various relative water depths across the entire range,excluding the extremely shallow zone.A novel analysis procedure was developed,which proved to be highly productive and can be considered a general method for data ***,the study yielded two conclusions:(1)the solitary-wave-like form is remarkably effective in formulating overtopping test data generated by irregular waves,regardless of whether the vertical wall is simple or composite,and(2)the resulting formulas exhibit definitely better performance compared with existing formulas.

关键词： solitary-wave-like form overtopping discharge overtopping formula vertical wall

Oxygen-assisted zinc recovery from electric arc furnace dust using magnesium chloride

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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2300-2311页

作者： Jingdong Huang xiao yang School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027China School of Engineering Westlake UniversityHangzhou 310030China

Electric arc furnace(EAF)dust is an important secondary resource containing metals,such as zinc(Zn)and iron(Fe).Recover-ing Zn from EAF dust can contribute to resource recycling and reduce environmental ***,the high chemical stability of ZnFe_(2)O_(4)in EAF dust poses challenges to Zn *** address this issue,a facile approach that involves oxygen-assisted chlorination using molten MgCl_(2)is *** work focused on elucidating the role of O2 in the reaction between ZnFe_(2)O_(4)and molten MgCl_(2).The results demonstrate that MgCl_(2)effectively broke down the ZnFe_(2)O_(4)structure,and the high O2 atmosphere considerably promoted the sep-aration of Zn from other components in the form of ZnCl_(2).The presence of O2 facilitated the formation of MgFe_(2)O_(4),which stabilized Fe and prevented its ***,the excessive use of MgCl_(2)resulted in increased evaporation loss,and high temperatures pro-moted the rapid separation of *** on these findings,we successfully extracted ZnCl_(2)-enriched volatiles from practical EAF dust through oxygen-assisted *** optimized conditions,this method achieved exceptional Zn chlorination percentage of over 97%within a short period,while Fe chlorination remained below 1%.The resulting volatiles contained 85wt%of ZnCl_(2),which can be further processed to produce metallic *** findings offer guidance for the selective recovery of valuable metals,particularly from solid wastes such as EAF dust.

关键词： electric arc furnace dust zinc oxygen magnesium chloride chlorination