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One-step synthesis and electromagnetic absorption properties of high entropy rare earth hexaborides(HE REB6)and high entropy rare earth hexaborides/borates(HE REB6/HE REB03)composite powders

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Journal of Advanced Ceramics 2021年第1期10卷 62-77页

作者： Weiming ZHANG Biao ZHAO Huimin XIANG Fu-Zhi dai Shijiang WU Yanchun ZHOU Science and Technology on Advanced Functional Composite Laboratory Aerospace Research Institute of Materials&Processing TechnologyBeijing 100076China Henan Key Laboratory of Aeronautical Materials and Application Technology School of Material Science and EngineeringZhengzhou University of AeronauticsZhengzhou 450046China Zibo Firststar New Material Incorporated Co. Ltd.Zibo 255000China

Considering the emergence of severe electromagnetic interference problems,it is vital to develop electromagnetic(EM)wave absorbing materials with high dielectric,magnetic loss and optimized impedance ***,realizing the synergistic dielectric and magnetic losses in a single phase material is still a ***,high entropy(HE)rare earth hexaborides(REB6)powders with coupling of dielectric and magnetic losses were designed and successfully synthesized through a facial one-step boron carbide reduction method,and the effects of high entropy borates intermedia phases on the EM wave absorption properties were *** HE REB6 ceramics including(Ce0.2Y0.2Sm0.2Er0.2Yb0.2)B6,(Ce0.2Hu0.2Sm0.2Er0.2Yb0.2)B6,(Ce0.2Y0.2Eu0.2Er0.2Yb0.2)B6,(Ce0.2Ya2Sm0.2Eu0.2Yb0.2)B6,and(Nd0.2Y0.2Sm0.2Eu0.2Yb0.2)B6 possess CsCl-type cubic crystal structure,and their theoretical densities range from 4.84 to 5.25 g/cm^(3).(Ce02Y0.2Sm0.2Er0.2Yb02)B6 powders with the average particle size of 1.86 jim were found to possess the best EM wave absorption properties among these *** RLmin value of(Ce0.2Y0.2Sm0.2Er0.2Yb0.2)B6 reaches-33.4 dB at 11.5 GHz at thickness of 2 mm;meanwhile,the optimized effective absorption bandwidth(EAB)is 3.9 GHz from 13.6 to 17.5 GHz with a thickness of 1.5 *** introduction of HE REB03(RE=Ce,Y,Sm,Eu,Er,Yb)as intermediate phase will give rise to the mismatching impedance,which will further lead to the reduction of reflection ***,the HEREB6/HEREB03 still possess wide effective absorption bandwidth of 4.1 GHz with the relative low thickness of 1.7 *** the better stability,low density,and good EM wave absorption properties,HE REB6 ceramics are promising as a new type of EM wave absorbing materials.

关键词： high entropy rare earth hexaborides(HE REB6) one-step synthesis electromagnetic wave absorbing properties synergistic dielectric and magnetic losses wide effective absorption bandwidth

Using data-limited approaches to assess data-rich Indian Ocean bigeye tuna:Data quantity evaluation and critical information for management implications

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Acta Oceanologica Sinica 2022年第3期41卷 11-23页

作者： Ya'nan Li Jiangfeng Zhu Xiaojie dai Dan Fu Yong Chen College of Marine Sciences Shanghai Ocean UniversityShanghai 201306China School of Marine Sciences University of MaineOronoME 04469USA Key Laboratory of Oceanic Fisheries Exploration Ministry of Agriculture and Rural AffairsShanghai 201306China Indian Ocean Tuna Commission Victoria 361Seychelles

The majority of fishery stocks in the world are data limited,which limits formal stock *** the impacts of input data on stock assessment is critical for improving stock assessment and developing precautionary management *** compare catch advice obtained from applications of various datalimited methods(DLMs)with forecasted catch advice from existing data-rich stock assessment models for the Indian Ocean bigeye tuna(Thunnus obesus).Our goal was to evaluate the consistency of catch advice derived from data-rich methods and data-limited approaches when only a subset of data is *** Stock Synthesis(SS)results were treated as benchmarks for comparison because they reflect the most comprehensive and best possible scientific information of the *** study indicated that although the DLMs examined appeared robust for the Indian Ocean bigeye tuna,the implied catch advice differed between data-limited approaches and the current assessment,due to different data inputs and model *** DLMs tended to provide more optimistic catch advice compared with the SS,which was mostly influenced by historical catches,current abundance and depletion estimates,and natural mortality,but was less sensitive to life-history parameters(particularly those related to growth).This study highlights the utility of DLMs and their implications on catch advice for the management of tuna stocks.

关键词： stock assessment bigeye tuna data-limited fisheries management Indian Ocean

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基于学科间差异信息的协同优化改进算法

国防科技大学学报 2008年第2期30卷 128-134页

作者：冯向军戴金海国防科技大学航天与材料工程学院湖南长沙410073

分析了MDO(Multidisciplinary Design Optimization)中广泛应用的协同优化算法的特点和存在的问题,提出了一种基于学科间差异信息的协同优化改进算法COMI(Collaborative Optimization based on Multidisciplinary Inconsistency)。利用学科间差异信息构造了系统级松弛约束和系统级罚函数,利用遗传算法作为系统级优化算法,并采用标准算例比较了标准CO(Collaborative Optimization)算法、松弛CO算法与COMI算法的性能。结果表明COMI算法在设计结果可行性和最优值上平衡性较好。

关键词：协同优化学科间差异多学科设计优化

Artificially regulated synthesis of nanocrystals in live cells

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National Science Review 2022年第6期9卷 189-199页

作者： An-An Liu En-Ze Sun Zhi-Gang Wang Shu-Lin Liu dai-Wen Pang State Key Laboratory of Medicinal Chemical Biology Tianjin Key Laboratory of Biosensing and Molecular Recognition Frontiers Science Center for New Organic MatterResearch Center for Analytical SciencesCollege of ChemistrySchool of MedicineFrontiers Science Center for Cell Responses Nankai University College of Chemistry and Molecular Sciences Wuhan University

Live cells, as reservoirs of biochemical reactions, can serve as amazing integrated chemical plants where precursor formation, nucleation and growth of nanocrystals, and functional assembly, can be carried out accurately following an artificial program. It is crucial but challenging to deliberately direct intracellular pathways to synthesize desired nanocrystals that cannot be produced naturally in cells, because the relevant reactions exist in different spatiotemporal dimensions and will never encounter each other *** article summarizes the progress in the introduction of inorganic functional nanocrystals into live cells via the ‘artificially regulated space–time-coupled live-cell synthesis’ strategy. We also describe ingenious bio-applications of nanocrystal–cell systems, and quasi-biosynthesis strategies expanded from live-cell synthesis. Artificially regulated live-cell synthesis—which involves the interdisciplinary application of biology, chemistry, nanoscience and medicine—will enable researchers to better exploit the unanticipated potentialities of live cells and open up new directions in synthetic biology.

关键词： cell synthesis nanocrystal quantum dot artificial metabolism

A New Pyridine-substituted Azadithiolate 2Fe2S Complex Related to the Active Site of[FeFe]-hydrogenase

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Chinese Journal of Structural Chemistry 2016年第2期35卷 237-245页

作者： XU Fen-Fen feng Ya-Nan DU Shao-Wu CHEN Yi-feng No.2 Middle School of Nanchang Jiangxi 330006China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

A new 2Fe2 S complex[（2-C5H4N）N（μ-CH2S）2Fe2（CO）6]（1） related to the active site of[FeFe]-hydrogenase was obtained by treating（HS）2Fe2（CO）6 with（pyridin-2-ylazanediyl）*** occurred at the pyridine nitrogen atom when two equivalents of HBF4·OEt2acid were added to the toluene solution of 1,leading to the formation of[（2-C5H4NH）N（μ-CH2S）2Fe2（CO）6]·BF4·OEt2（1H~＋）,whose molecular structure was further established by singlecrystal X-ray *** 1 crystallizes in the monoclinic system,space group P21/n with α=7.728（3）,b = 11.825（4）,c = 17.888（6） A,β= 92.968（5）°,while complex 1H~＋ crystallizes in the triclinic system,space group P1 with a = 7.672（4）,b = 10.382（5）,c = 16.480（10） A,α=106.575（13）,β= 93.18（3）,γ=104.262（17）°.

关键词： bioinorganic chemistry [FeFe]-hydrogenase protonation proton reduction

An efficient method of addressing ectopic beats:new insight into data preprocessing of heart rate variability analysis

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第12期12卷 976-982页

作者： feng WEN Fang-tian HE College of Life Science Zhejiang University Hangzhou 310027 China ECG Department Sir Run Run Shaw Hospital School of Medicine Zhejiang University Hangzhou 310016 China

Heart rate variability(HRV) analysis is affected by ectopic *** efficient method was proposed to deal with the ectopic *** method was based on trend correlation of the heart timing *** of R-R interval(RRI) value at ectopic beat time was constructed by the weight calculation and the slope estimation of preceding normal *** type of ectopic beat was detected and replaced by the predictor of *** performance of the simulated signal after ectopic correction was tested by the standard value using power spectrum density(PSD) estimation,whereas the results of clinical data with ectopic beats were compared with the adjacent ectopic-free *** result showed the frequency indexes after ectopy corrected had less error than other methods with the test of simulated signal and clinical *** indicated our method could improve the PSD estimation in HRV *** method had advantages of high accuracy and real time properties to recover the sinus node modulation.

关键词： Frequency domain Ectopic beat Heart rate variability(HRV) Power spectrum density

Theory of Nonequilibrium Coherent Transport Through an Interacting Mesoscopic Region Weakly Coupled to Electrodes

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Communications in Theoretical Physics 2003年第3X期40卷 369-374页

作者： ZHUYu LINTsung-Han SUNQing-feng StateKeyLaboratoryforMesoscopicPhysicsandDepartmentofPhysics PekingUniversityBeijing100871China CenterforthePhysicsofMaterialsandDepartmentofPhysics McGillUniversityMontrealPQCanadaH3A2T8

We develop a theory for the nonequilibrium coherent transport through a mesoscopic region, based on the nonequilibrium Green function technique. The theory requires the weak coupling between the central mesoscopic region and the multiple electrodes, but allows arbitrary hopping and interaction in the central region. An equation determining the nonequilibrium distribution in the central interacting region is derived and plays an important role in the *** theory is applied to two special cases for demonstrations, revealing the novel effects associated with the combination of phase coherence, Coulomb interaction, and nonequilibrium distribution.

关键词：非平衡态一致性输运中观系统格林函数电子崩溃

Cooperative Supramolecular Polymerization of Propeller-Shaped Triphenylamine Cyanostilbenes for Explosive Detection

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Chinese Journal of Polymer Science 2023年第4期41卷 585-592,I0009页

作者： Long-Yu Guang Zhi-feng Zhou Yi-Fei Zhang Lai-Wei Gao feng Wang rui Liao CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei230026China Clinical Laboratory The Second People’s Hospital of HefeiHefei230011China

Self-assembly ofπ-conjugated compounds into supramolecular polymers has received considerable attention because of their intrinsic scientific interests and technological *** compared toπ-conjugated rods,discotics,and macrocycles,propeller-shapedπ-conjugated molecules have been less exploited to form long-range-ordered supramolecular *** a novel type of supramolecular polymers has been constructed on the basis of propeller-shaped triphenylamine *** designed compound adopts nucleation-elongation cooperative mechanism for the supramolecular polymerization process,because of the participation of three-fold hydrogen bonds between the neighbouring *** supramolecular polymeric state displays amplified chirality and enhanced emission than those in the monomeric *** resulting supramolecular polymers exhibit severe emission quenching upon addition of 2,6-dinitrotoluene,ascribed to photoinduced electron transfer from the triphenylamine cyanostilbenes to the explosive *** current study proves the feasibility to supramolecular polymerize propeller-likeπ-conjugated molecules,serving as a promising type of explosive sensor owing to their guest encapsulation and signal amplification capabilities.

关键词： Supramolecular polymers D-π-A molecules Supramolecular chirality Fluorescence Explosive detection

Studies on the flame propagation characteristic and thermal hazard of the premixed N2O/fuel mixtures

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Defence Technology（防务技术） 2020年第3期16卷 564-570页

作者： Yu-yan Li Rong-pei Jiang Zhi-peng Li Sen Xu feng Pan Li-feng Xie School of Chemical Engineering Nanjing University of Science and TechnologyNanjingJiangsu 210094PR China Beijing Insitute of Aerospace Testing Technology Beijing Key Laboratory of Research and Application for Aerospace Green PropellantsBeijing 100074PR China National Quality Supervision and Inspection Center for Industrial Explosive Materials NanjingJiangsu 210094PR China

An experimental study was carried out to investigate the flame propagation and thermal hazard of the premixed N2O/fuel mixtures,including NH3,C3H8 and *** study provided the high speed video images and data about the flame locations,propagation patterns,overpressures and the quenching diameters during the course of combustion in different channels to elucidate the dynamics of various combustion *** onset decomposition temperature was determined using high-performance adiabatic *** was shown that the order of the flame acceleration rate and thermal hazard was N2O/C2H4>N2O/C3H8>N2O/NH3.

关键词： Flame propagation Flame acceleration rate Quenching diameter Thermal hazard