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Uniaxial compression CT and acoustic emission test on the coal crack propagation destruction process

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Journal of Coal Science & Engineering(China) 2013年第1期19卷 69-74页

作者： Jing-hong LIU Yao-dong JIANG yi-xin ZHAO Jie ZHU College of Urban and Rural Construction Agricultural University of Hebei Baoding 071001 China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and Technology Beijing 100083China School of Mechanics & Civil Engineering China University of Mining & Technology Beijing 100083 China

Acoustic emission test and CT scanning are important techniques in the study of coal crack propagation. A uniaxial compression test was performed on coal samples by integrating CT and acoustic emission. The test comparison analyzes the acoustic emission load and CT images for an effective observation on the entire process, from crack propagation to the samples＇ destruction. The box dimension of the coal samples＇ acoustic emission series and the CT images were obtained through calculations by using the authors＇ own program. The results show that the fractal dimension of both the acoustic emission energy and CT image increase rapidly, indicating coal and rock mass has entered a dangerous condition. Hence, measures should be taken to unload the pressure of the coal and rock mass. The test results provide intuitive observation data for the coal meso-damage model. The test contributes to in-depth studies of coal or rock crack propagation mechanisms and provides a theoretical basis for rock burst mechanism.

关键词： acoustic emission test CT test fractal dimension destruction process

Bioinspired Design of Reversible Fluorescent Probes for Tracking Nitric Oxide Dynamics in Live Cells

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CCS Chemistry 2021年第10期3卷 116-128页

作者： Rui-ying Guo Yu-Tian zhang Supphachok Chanmungkalakul Hao-Ran Guo Yongzhou Hu Jia Li Xiaogang Liu yi Zang xin Li College of Pharmaceutical Sciences Zhejiang UniversityHangzhou 310058 State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203 University of Chinese Academy of Sciences Beijing 100049 Fluorescence Research Group Singapore University of Technology and DesignSingapore 487372 Open Studio for Druggability Research of Marine Natural Products Pilot National Laboratory for Marine Science and TechnologyQingdao 266237

Nitric oxide(NO)participates in various pathways and revealing its dynamics is critical for resolving its *** there are methods available for detecting biological NO,few are capable of tracking NO ***,inspired by the cellular machinery of reversible thiol modification by NO,we have successfully designed a family of cysteine analogues tagged with fluorophores for visualizing cellular NO dynamics.

关键词： fluorescent probe fluore scence imaging reversible nitric oxide S-nitrosation

A new method to solve project scheduling problems with multi-skilled workforce constraints

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A new method to solve project scheduling problems with multi...

Taxonomic review of East Palearctic species of Synergus section I, with description of a new species from China (Hymenoptera: Cynipidae: Cynipinae)

第25届中国控制与决策会议

作者： WANG yi-fan SUN Fu-quan LIU Shi-xin CHEN Di College of Information Science & Engineering Northeastern University Northeastern University at Qinhuangdao

ISBN: (纸本)9781467355339

With the developing of technology and economic of society, skilled workforce has been playing as the key role through the trend of prosperity. Project scheduling problems with multi-skilled workforce constraints （PSPMSWC） have become a research hotpot in the field of human resource allocation and project scheduling. Following the description and model of the PSPMSWC, a hybrid Benders decomposition （HBD） algorithm is presented in detail as well as the scheme of total solving process with heuristic inferring. After the programming and solving operation, results are gathered and analyzed afterward with conclusion at last.

关键词： Project Scheduling Multi-skilled workforce Hybrid Benders decomposition Heuristic inferring

来源： cnki会议评论

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Zoological Systematics 2014年第4期39卷 534-544页

作者： Juli Pujade-Villar yi-Ping Wang Xue-xin Chen Jun-Hua He Department of Animal Biology Barcelona University College of Forest and Biotechnology Zhejiang Agricultural and Forestry University Institute of Insect Sciences College of Agriculture and Biotechnology Zhejiang University

A taxonomic review is provided for the Section I of the inquiline gallwasp genus Synergus, including the description of a new species from China, S. deqingensis Pujade-Villar, Wang ＆ Chen sp. nov. and redescription of all previously known species of the section from the that region. Synergus jezoensis Uchida ＆ Sakagami, 1948, a species previously considered of uncertain status from Japan, is treated herein as a valid species, and is redescribed and reported for the first time from China. Andricus mukaigawae（Mukaigawa, 1913） and its inquiline, S. japonicus, are reported for the first time from China. A key is provided to all four East Palearctic species in Section I of Synergus.

关键词： Cynipidae inquiline Synergus taxonomy China

Rigid Dysprosium(Ⅲ)Single-Molecule Magnets Exhibit Preserved Superparamagnetism in Solution

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Chinese Journal of Chemistry 2022年第5期40卷 563-570页

作者： Xiali Ding Qiancheng Luo Yuanqi Zhai Xufeng zhang yi Lv xinliang zhang Chao Ke Chao Wu Yanzhen Zheng Frontier Institute of Science and Technology(FIST) State Key Laboratory of Mechanical Behavior for MaterialsMOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed MatterXi'an Key Laboratory of Sustainable Energy and Materials ChemistrySchool of Chemistry and School of PhysicsXi'an Jiaotong University99 Yanxiang RoadXi'anShaanxi710054 China Department of Hepatobiliary Surgery and The First Affiliated Hospital of Xi'an Jiaotong University 277 West Yanta RoadXi'anShaanxi710061 China Department of Spine Surgery Honghui HospitalXi'an Jiaotong University76 Nanguo RoadXi'anShaanxi710054 China Department of Orthopaedics and Trauma Hong Hui HospitalCollege of MedicineXi'an Jiaotong University555 East Youyi RoadXi'anShaanxi710054 China

Molecules with long preserved magnetic moments are perceived as the smallest units for storing bytes,which could bring a new revolution for information ***,the rational design of such molecules remains *** two rigid adamantanol ligand based dysprosium(III)complexes([Dy(1-AdO)_(2)(py)_(5)]BPh_(4)-1 and[Dy(2-AdO)_(2)(py)_(5)]BPh_(4)-2)with pentagonal-bipyramidal coordination geometry and local D5h symmetry were successfully prepared,which display excellent single-molecule magnet(SMM)behavior(U_(eff)≈1835 K,T_(B)_(ZFC)≈24 K,T_(B)^(100s)≈17 K and T_(B)^(H)=23 K for 1;U_(eff)≈1756 K,T_(B)^(ZFC)≈20 K,T_(B)^(100s)≈16 K and T_(B)^(H)=23 K for 2)due to the much weakened vibration in low energy ***,the large energy barriers and high blocking temperatures for these two complexes in solid states are well preserved in *** is never observed in previous studies of SMMs,indicating that the adamantanol is rigid and can be introduced to make the composed molecules stable enough to maintain the solid state magnetic property in solution.

关键词： Molecularmagnets Lanthanide D_(sh)-symmetry Superparamagnetism Solution

A trefoil-shaped macrocycle with [12]-imidazolium cations

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Chinese Chemical Letters 2022年第10期33卷 4567-4571页

作者： Le zhang Li-ying Sun Jin-Ping Chang Hui-Yu Xie Ya-Wen zhang yi-Fan zhang ying-Feng Han Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry and Materials ScienceNorthwest UniversityXi'an 710127China

A trefoil-like two-dimensional(2D)C_(3v) symmetric organic[12]-imidazolium cation H_(12)-2(PF_(6))_(12) featuring three[4]-imidazolium macrocycles was synthesized in three *** reaction of a dodecakis H_(12)-1(PF_(6))_(12) imidazolium salt with Ag_(2)O resulted in the formation of a hexanuclear AgI dodecacarbene assembly[Ag_(6)(1)](PF_(6))_(6).Upon UV irradiation,the photodimerization of the cinnamic ester pendants of[Ag_(6)(1)](PF_(6))_(6) led to the generation of a trefoil-like complex[Ag_(6)(2)](PF_(6))_(6) containing three closed *** of metal ions allowed for the synthesis of the target *** complexes were fully characterized by NMR spectroscopy(^(1)H,^(13)C{^(1)H}and 2D NMR)and high-resolution electrospray ionization mass spectrometry(HR-ESI-MS).

关键词： Trefoil-shaped macrocycle N-Heterocyclic carbenes Photochemical reaction Imidazolium

Quantum confinement effect in β-SiC nanowires

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Frontiers of physics 2018年第4期13卷 117-122页

作者： Gang Peng Xiaoyan Yu Yan-Lan He Gong-yi Li yi-xing Liu xinfang zhang Xue-Ao zhang college of Science National University of Defense Technology Changsha 410073 China School of Electronic Communication Engineering Guiyang University Guiyang 550005 China

The quantum confinement effect is important in nanoelectronics and optoelectronics applications; however, there is a discrepancy between the theory of quantum confinement, which indicates that band-gap widening occurs only at small sizes, and experimental observations of band-gap widening in large-diameter nanowires （NWs）. This paper reports an obvious blue shift of the absorption edge in the UV-visible absorption spectra of SiC NWs with diameters of 50-300 nm. On the basis of quantum confinement theory and high-resolution transmission electron microscopy images of SiC NWs, band-gap widening in SiC NWs with diameters of up to hundreds of nanometers is fully explained; the results could help to explain similar band-gap widening in other NWs with large diameters.

关键词： quantum confinement effect SiC nanowires (SiC NWs) band gap

Non-universal Fermi polaron in quasi two-dimensional quantum gases

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Chinese Physics B 2022年第8期31卷 246-251页

作者： Yue-Ran Shi Jin-Ge Chen Kui-yi Gao Wei zhang Department of Physics Renmin University of ChinaBeijing 100872China Beijing Academy of Quantum Information Sciences Beijing 100193China Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices Renmin University of ChinaBeijing 100872China

We consider an impurity problem in a quasi-two-dimensional Fermi gas, where a spin-down impurity is immersed in a Fermi sea of N spin-up atoms. Using a variational approach and an effective two-channel model, we obtain the energy for a wide range of interaction strength and for various different mass ratios between the impurity and the background fermion in the context of heteronuclear mixture. We demonstrate that in a quasi-two-dimensional Fermi gas there exists a transition of the ground state from polaron in the weakly interacting region to molecule in the strongly interacting *** critical interaction strength of the polaron–molecule transition is non-universal and depends on the particle density of the background Fermi sea. We also investigate the excited repulsive polaron state, and find similar non-universal behavior.

关键词： Fermi gas polaron problem two-channel model

Size-induced effect on cathode luminescence spectra of CsI(Na) and CsI(Tl) crystals

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Science China(Physics,Mechanics & Astronomy) 2014年第9期57卷 1684-1688页

作者： LIU Fang OUYANG XiaoPing LIU Bin LIU JinLiang CHEN Liang zhang ZhongBing zhang XueBin FENG yi Radiation Detection Research Center Northwest Institute of Nuclear Technology School of Nuclear Science and Engineering North China Electric Power University Department of Engineering Physics Tsinghua University School of Materials Science and Engineering Hefei University of Technology

We investigated the cathode luminescence characteristics of CsI(Na)and CsI(Tl)crystals by the spectrum and structure properties at room *** fabricated three different sizes of CsI(Na)and CsI(Tl)crystals and measured their luminescence spectra under cathode *** found that CsI(Na)cathode luminescence peaks appear at 420 and 305 nm,and CsI(Tl)cathode luminescence peaks are 540 and 410 nm,the grain size affects CsI(Na)luminescence significantly,and the Na-related420 nm luminescence intensified relatively when the average grain size reaches^20μm,which becomes weak when the grain size is down to *** the cathode luminescence spectra of CsI(Tl)crystals with different size have no obvious *** explanations for these phenomena are that the different impurities in the same host material CsI lead to different luminescence *** cathode luminescence characteristics indicate the suitability of CsI(Na)and CsI(Tl)crystals to match photomultiplier tube for large area crystal detector development.

关键词： CsI(Na) crystal CsI(Tl) crystal cathode luminescence spectrum