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Chinese Chemical Letters 2018年第10期29卷 1513-1516页

作者： Simeng Wang Yanan zhang Longhua zhang min zhang Changlin Tian School of Life Science Anhui University Hefei 230039 China National Laboratory of Physical Sciences at Microscale and School of Life Science University of Science and Technology of China Hefei 230027 China High Magnetic Field Laboratory Chinese Academy of Sciences Hefei 230031 China

Fluorescence lifetime and anisotropy has become a prevalent tool to detect the structure change and motility property of proteins. YgaP is the only membrane-integrated rhodanese in E. coli. The sulfur transfer process has been characterized by various studies. However, the mechanism of the outward transportation of SCN-remains unclear. In this work, we examined the fluorescence lifetime and anisotropy of site-specific incorporated unnatural amino acid 7-HC to study the conformational change of YgaP upon SCN-binding. We also compared the fluorescence changes between detergent-wrapped environment in DPC and intact native membrane environment in SMA. Our results suggested the presence of at least two different conformations in YgaP protein. Both the residues in the middle of TMH2 and the residues near extracellular side play important roles in the binding and/or output of SCN-. SMA is a good material to reflect the in situ conformation changes of protein than micelles.

关键词： Rhodanese YgaP Fluorescence lifetime and anisotropy SMA Conformation change

A document-level model for tweet event detection

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High Technology Letters 2018年第2期24卷 208-218页

作者： Qin Yanxia zhang Yue zhang min Zheng Dequan School of Computer Science and Technology Harbin Institute of Technology Harbin 150001 P. R. China Information Systems Technology and Design Singapore University of Technology and Design Singapore 487372 Singapore School of Computer Science and Technology Soochow University Suzhou 215006 P. R. China

Social media like Twitter who serves as a novel news medium and has become increasingly popular since its establishment. Large scale first-hand user-generated tweets motivate automatic event detection on Twitter. Previous unsupervised approaches detected events by clustering words. These methods detect events using burstiness,which measures surging frequencies of words at certain time windows. However,event clusters represented by a set of individual words are difficult to understand. This issue is addressed by building a document-level event detection model that directly calculates the burstiness of tweets,leveraging distributed word representations for modeling semantic information,thereby avoiding sparsity. Results show that the document-level model not only offers event summaries that are directly human-readable,but also gives significantly improved accuracies compared to previous methods on unsupervised tweet event detection,which are based on words/segments.

关键词： social media event detection twitter bursty unsupervised document-level

Large area crystalline Weyl semimetal with nano Au film based micro-fold line array for THz detector

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Science China(Technological Sciences) 2023年第11期66卷 3267-3275页

作者： SONG Qi ZHOU Yu JIA ErSe WANG JiaTong zhang min zhang BingYuan Shandong Key Laboratory of Optical Communication Science and Technology School of Physics Science and Information TechnologyLiaocheng UniversityLiaocheng 252059China North China Institute of Computing Technology Beijing 100083China Key Laboratory of Optoelectronic Devices and Systems of ministry of Education and Guangdong Province College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China School of Precision Instrument and Opto-electronics Engineering Tianjin UniversityTianjin 300072China

The advancement of 6G technology relies on the development of high-performance terahertz detectors that can operate at room *** detectors are crucial for Internet of Things(Io T)applications,which require sensitive environmental sensing and efficient reception of 6G *** significant research focus is on detection technology with high responsiveness and low equivalent noise power for 6G signals,which experience high losses in the *** meet the demand for ultra-sensitive detectors in 6G technology,we have employed several ***,we prepared a large area of Weyl-semimetal layer through magnetron ***,we obtained a high-quality Weyl-semimetal active layer by carefully controlling the annealing ***,a thin nano-Au layer was introduced as a micro-cavity reflection layer to enhance the device's detection ***,we incorporated an electromagnetic induction well to improve carrier confinement and enhance the detection *** proposed high-performance terahertz detector,with its potential for industrial production,offers a valuable technical solution for the advancement of 6G technology.

关键词： micro-cavity Weyl semimetal crystalline thin film THz device

Geochemical Characteristics of C_5–C_7 Light Hydrocarbons in Gas Hydrates from the Permafrost Region of Qilian Mountains

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Acta Geologica Sinica(English Edition) 2016年第6期90卷 2283-2284页

作者： zhang min KONG Ting HE Yu Key Laboratory of Exploration Technology for Oil & Gas Research Yangtze UniversityMinistry of Education College of Resources and Environment Yangtze University

As an important part of gas hydrates, light hydrocarbons （LHs）, especially C5 to C7 hydrocarbons with various monomer compounds, provide a wide variety of geological and geochemical information, which have received ... 详细信息

关键词： Geochemical Characteristics of C5 C7 Light Hydrocarbons in Gas Hydrates from the Permafrost Region of Qilian Mountains

New method to identify optimal discontinuity set number of rock tunnel excavation face orientation based on Fisher mixed evaluation

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Underground Space 2024年第4期17卷 300-319页

作者： Keshen zhang Wei Wu min zhang Yongsheng Liu Yong Huang Baolin Chen College of Civil Engineering Tongji UniversityShanghai 200092China Key Laboratory of Geotechnical and Underground Engineering of ministry of Education Tongji UniversityShanghai 200092China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China Shudao Investment Group Co.Ltd Chengdu 610095China China Railway Tunnel Group Co.Ltd Guangzhou 511466China China Railway First Survey and Design Institute Group Co.Ltd Xi’an 710043China Zhejiang Institute of Communications Co.Ltd Hangzhou 310012China

Discontinuity is critical for strength,deformability,and permeability of rock *** information is one of the essential discontinuity characteristics and is usually accessed by orientation *** methods of identifying optimal discontinuity set numbers are usually achieved by clustering validity indexes,which mainly relies on the aggregation and dispersion of clusters and leads to the inaccuracy and instability of *** paper proposes a new method of Fisher mixed evaluation(FME)to identify optimal group numbers of rock mass discontinuity *** FME,orientation distribution is regarded as the superposition of Fisher mixed *** grouping results are identified by considering the fitting accuracy of Fisher mixed distributions,the probability monopoly and central location significance of independent Fisher centers.A Halley-Expectation-Maximization(EM)algorithm is derived to achieve an automatic fitting of Fisher mixed *** real rock discontinuity models combined with three orientation clustering algorithms are adopted for discontinuity *** clustering validity indexes are used to automatically identify optimal group numbers for *** results show that FME is more accurate and robust than the other clustering validity indexes in optimal discontinuity group number identification for different rock models and orientation clustering algorithms.

关键词： Rock mass discontinuity Orientation grouping Fisher mixed distribution 3D point cloud Stereo photogrammetry

Carbazole-type compounds in crude oils

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Chinese Science Bulletin 1998年第8期43卷 669-672页

作者： min zhang Tingsheng Xiang Bowen Mei Jianghan Petr Inst Anal & Res Ctr Jingzhou 434102 Peoples R China

Carbazole_type compounds were analyzed using GC and GC_MS_MS. A relatively high concentration of carbazole_type compounds was detected in crude oils of different types (marine and non_marine) and different maturities (low mature and mature) in Tarim, Liaohe and Keilu basins. The results suggest the ratios of 1, 8-dimethyl-/2, 7-dimethylcarbazole and benzo carbazole/benzo carbazole might be taken as petroleum migration parameters.

关键词： crude oil carbazole_type compound.

Mono-Allylation of Gem-Diacetates with Allylsamarium Bromide

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Chinese Chemical Letters 2001年第11期12卷 943-944页

作者： Xiao Xia WANG Yong min zhang Department of Chemistry Zhejiang University(Xixi Campus)Hangzhou 310028 Laboratory of Organometallic Chemistry Chinese Academy of SciencesShanghai 200032

The substitution reaction between gem-diacetates and allylsamarium bromide was investigated, and homoallylic alcohol acetates were obtained in moderate to good yields.

关键词： gem-diacetates substitution monoallylation allylsamarium bromide

Study on the Interface Bonding and Bending Fatigue Properties of Aluminum Alloy Foam Sandwich

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稀有金属材料与工程 2009年第A03期38卷 119-122页

作者： zhang min Chen Changjun Chang Qingming Key Laboratory for Ferrous Metallurgy and Resources Utilization of ministry of Education Wuhan University of Science ＆ Technology Wuhan 430081 China

Foam materials have many attractive properties because of their low-weight and cell structure. By sandwiches with an aluminum-foam core, it is possible to obtain higher structural stiffness and rigidity, maintain stability against buckling and additionally make use of the high energy dissipation capability of the bare foams. The most obvious and straightforward one is adhesive bonding of pre-fabricated aluminum foams and metal face sheets. A new manufacture processing is proposed for preparation of aluminum alloy foam sandwich, ie., Al-plate/mixed element powder/ Al-plate are sandwich rolled together by a large reduction in pass, which is then foamed in heating furnace to manufacture end-use product. Aluminum alloy foam sandwich is obtained in this experiment. The experimental results showed that the process of rolling interface belongs to mechanical bonding, whose mechanism is film theory. While interface bonding belong to metallurgy bonding in the process of foaming, Al atom interdiffused in the interface, and no new phase was generated in the foaming process of aluminum face sheet/powders precursor. Bending fatigue test results showed that the bonding force of the foamed sandwich interface is very high, in fatigue test fracture occurred in the whole foam aluminum sandwich panels and Al/foam core interface was not laminated.

关键词：泡沫材料复合材料泡沫塑料物理性能

New Discoveries of the Influence of Sedimentary Environment on Rearranged Hopanes in Source Rocks

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Acta Geologica Sinica(English Edition) 2017年第2期91卷 747-748页

作者： LI Jin zhang min KONG Ting Key Laboratory of Exploration Technology for Oil&Gas Research(Yangtze University) Ministry of EducationWuhan 430100Hubei China College of Resources and Environment Yangtze UniversityWuhan 430100HubeiChina Research Institute of Petroleum Exploration and Development(Langfang Branch) PetroChinaLangfang 065007HebeiChina The Key Laboratory of Gas Formation and Development PetrochinaLangfang 065007HebeiChina

Objective The distribution of rearranged hopanes in hydrocarbon source rocks is influenced by thermal maturity and original source input, and is also controlled by depositional conditions. Through comparison of lacustrine and coal-bearing source rocks, this work attempted to analyze the composition and origin of rearranged hopanes in hydrocarbon source rocks. Taken the source rocks from the Songliao Basin, Ordos Basin and Kuqa Depression as examples, we aimed to investigate the effect of the redox conditions, water salinity and oxygen content of the source-rock depositional environment on the formation of rearranged hopanes to provide theoretical basis for the genesis of rearranged hopanes.

关键词： New Discoveries of the Influence of Sedimentary Environment on Rearranged Hopanes in Source Rocks

Thermal Effects on Composition of Rearranged Hopanes in Hydrocarbon Source Rocks

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Acta Geologica Sinica(English Edition) 2017年第1期91卷 373-374页

作者： zhang min CHEN Julin JIANG Lian Key Laboratory of Exploration Technology for Oil & Gas Research Yangtze University Ministry of Education Wuhan 430100 Hubei China College of Resources and Environment Wuhan 430100 Hubei China

Objective The distribution characteristics and formation mechanism of rearranged hopanes in hydrocarbon source rocks are affected by various geological *** these geological conditions,thermal action has an important i... 详细信息

关键词： Thermal Effects on Composition of Rearranged Hopanes in Hydrocarbon Source Rocks Source