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A novel caged-prenylxanthone from Garcinia bracteata

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Chinese Chemical Letters 2010年第4期21卷 443-445页

作者： Na, Zhi Hu, Hua Bin fan, qing Fei Chinese Acad Sci Xishuangbanna Trop Bot Garden Mengla 666303 Peoples R China

A novel caged-prenylxanthone xanthone,neobractatin(1),was isolated from the twig of Garcinia *** structure was elucidated by spectroscopic methods,especially 2D NMR techniques.

关键词： Garcinia bracteata Caged-prenylxanthone Neobractatin

Primary dolostone related to the Cretaceous lacustrine hydrothermal sedimentation in qingxi sag, Jiuquan Basin on the northern Tibetan Plateau

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Science China Earth Sciences 2013年第4期56卷 2080-2093页

作者： WEN HuaGuo zheng RongCai qing HaiRuo fan MingTao LI YanAn GONG BoShi State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of Technology Institute of Sedimentary Geology Chengdu University of Technology Department of Geology University of Regina Yumen Oilfield Company of PetroChina

Based on comprehensive studies in petrography, petrofabric analysis and geochemistry, this paper describes a unique and rare laminated micritic ferruginous primary dolostone crystallized and precipitated from the alkaline hot brine under the conditions of the Mesozoic faulted lake basin. The main rock-forming mineral of this dolostone is ferruginous dolomite with a micritic structure. This dolomite mostly exhibits laminae of 0.1-1 mm thick and is often discovered with other minerals, such as albite, analcite, barite and dickite, which have at least two types of interbedded laminae. Petrogeochemistry reveals that this dolostone contains a large number of typomorphic elements of hydrothermal sedimentation, including Sb, Ba, Sr, Mn, and V. In addition, the LREE is in relatively high concentrations and possesses the typical REE distribution pattern with negative Eu anomaly. Oxygen isotope values （C^ISOpDB） range from 5.89%~ to 14.15%o with an average of 9.69%0. The ratio of 87Sr/86Sr is between 0.711648 and 0.719546, with an average of 0.714718. These data indicate that the depositional environment is a stable, blocked, anoxic low-lying hot brine pool in the bottom of deep lake controlled by basement faults. The hydrothermal fluid is the alkaline hot brine formed by the combination of the infiltration lake water and mantle-derived magmatic water, consisting of many ions, including Ca2＋, Mg2＋ and Fe2＋. Under the driving flow power of magmatic heat, gravity and compaction, the hy- drothermal fluid overcame the overburden pressure and hydrostatic pressure of the lake water body, and boiled to explosion, and then the explosion shattered the original laminated micritic ferruginous primary dolostone near the vent and then formed a new type of dolostone called shattered ＂hydroexplosion breccias＂. In the low-lying, unperturbed hot brine pool, far from the vent, the laminated micritic ferruginous primary dolostone was quickly crystallized and chemicals precipitated from the hy-

关键词： primary ferruginous dolostone hydrothermal sedimentation fault lakes Cretaceous Jiuquan Basin

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Structures of Not-finitely Graded Lie Algebras Related to Generalized Heisenberg–Virasoro Algebras

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Acta Mathematica Sinica,English Series 2015年第10期31卷 1517-1530页

作者： Guang Zhe fan Chen Hong ZHOU Xiao qing YUE Department of Mathematics Tongji University

In this paper, we study the structure theory of a class of not-finitely graded Lie alge- bras related to generalized Heisenberg-Virasoro algebras. In particular, the derivation algebras, the automorphism groups and th... 详细信息

关键词： Not-finitely graded Lie algebras generalized Heisenberg-Virasoro algebras derivations automorphisms 2-cocycles

Syntheses,Crystal Structures and Luminescent Properties of Three New Gallium Complexes Containing Pyridine-2,6-dicarboxylic Acid

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Chemical Research in Chinese Universities 2012年第6期28卷 936-941页

作者： ZHOU Guang-peng YANG Yu-lin fan Rui-qing Department of Chemistry Harbin Institute of Technology Harbin 150001 P. R. China

Three new gallium complexes formulated as [Ga（PDA）2 ][Ga（H2O）（PDA）（phen）]·4H2O（1）,[Ga（PDA） 2]·（H2IN）·2H2O（2） and [Ga（OH）（PDA）（H2O）] 2（3）（H2PDA=pyridine-2,6-dicarboxylic acid;phen=1,10-phenanthroline;HIN=isonicotinic acid） have been synthesized under hydrothermal *** the mixed-ligand system of complex 1,PDA2 and phen are connected to the central Ga 3＋ cation as tri-and bi-dentate ligands,*** complex 2,each Ga 3＋ cation is six-coordinated by two PDA 2 anions *** 3 shows a binuclear structure,with the bond distance of Ga1― Ga2 being 0.30061（3） *** 3D supramolecular structures of the three complexes are constructed via hydrogen bonds and aromatic π-π packing *** the three complexes exhibit intense blue emission at room temperature in the solid state,which are attributed to π＊-π transition centered on the ligands.

关键词： Gallium complex Crystal structure Luminescent property

Migration behavior of solid fuel particles during granulation process and its influence on combustion property

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Journal of Iron and Steel Research International 2023年第11期30卷 2153-2162页

作者： Zhi-yun Ji Yi-fan Wang Xiao-hui fan Gai-ge Zhao Min Gan Le-yun Tang Yong Tu Xiao-long Wang Hao-xiang zheng Xu-ling Chen Xiao-xian Huang Zeng-qing Sun School of Minerals Processing and Bioengineering Central South UniversityChangsha410083HunanChina Hunan Valin Xiangtan Iron and Steel Co. Ltd.Xiangtan411101HunanChina

Iron ore sintering process is the main CO_(2) emission source throughout the integrate steelworks,which primarily comes from the combustion of solid *** the combustion efficiency and reducing the solid fuel consumption are important ways to reduce the CO_(2) emission in the sintering *** the efficient combustion of fuel,the migration behavior and combustion characteristics of solid fuel in the granulation process were *** results indicated that during the granulation process,fuel particles with size less than 0.5 mm mainly migrated into the granules with grain size of 1-3,3-5 and 5-8 mm;fuel particles with size of 0.5^(-1)mm mainly migrated into granules of 1-3 mm;fuel particles with size of 1-3,3-5 and 5-8 mm mainly entered the granules with the same grain *** the increase in fuel particles grain size from-0.5 to+8 mm,the combustion efficiency exhibited a firstly-increasing and then decreasing tendency,while the NO_(x) exhibited a decreasing *** reason can be described that finer fuel particles(-1 mm)easily distributed in the outer layer of the granules,which combusted fiercely due to its larger specific surface area,leading to the development of incomplete combustion and the conversion of fuel nitrogen;the combustion efficiency of larger fuel particles was restricted by the inner diffusion of O_(2),which then contributed to the reduction of NO_(x) under the inadequate combustion atmosphere.

关键词： Iron ore sintering Granulation Solid fuel distribution Pollutant emission Combustion efficiency

Influence of oxygen-rich hot air composite gas medium on sintering performance and function mechanism

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Journal of Iron and Steel Research International 2024年第5期31卷 1071-1081页

作者： Min Gan Hao-xiang zheng Xiao-hui fan Zhi-yun Ji Qiang Li Ming Wu Yi-fan Wang Xiao-long Wang Yu-feng Wu Xu-ling Chen Zeng-qing Sun Xiao-xian Huang School of Minerals Processing and Bioengineering Central South UniversityChangsha410083HunanChina Shanxi Taigang Stainless Steel Co. Ltd.Taiyuan030003ShanxiChina

Hot air sintering technology is used to improve the quality and production efficiency of sintered ***,the current thick layer condition highlights the disadvantage of the low oxygen potential of the hot air sintering ***,it is considered to use oxygen enrichment sintering to improve the environment of hot air *** sintering,hot air sintering,and oxygen-rich hot air sintering were compared through sintering cup experiments,and the influence of hot air and oxygen-rich hot air on sintering indexes was *** air reduced the vertical sintering velocity,while improved the yield and tumbler ***-rich hot air sintering contributed to improving the vertical sintering velocity while ensuring the quality of sintered ore,thus comprehensively improving production *** the action of hot air,the highest temperature of the sintering layer increased and the high-temperature holding time was *** oxygen enrichment,the combustion efficiency of fuels in the upper layer of materials was promoted,which optimized heat distribution in the middle and lower layers of materials and increased the content of calcium ferrite in the sintered ore,thus strengthening the sintering process.

关键词： Iron ore sintering Hot air sintering Oxygen enrichment Function mechanism

Least squares twin support vector machine with asymmetric squared loss

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The Journal of China Universities of Posts and Telecommunications 2023年第1期30卷 1-16页

作者： Wu qing Li Feiyan Zhang Hengchang fan Jiulun Gao Xiaofeng School of Automation Xi'an University of Posts and TelecommunicationsXi'an 710121China School of Telecommunication and Information Engineering Xi'an University of Posts and TelecommunicationsXi'an 710121China

For classification problems,the traditional least squares twin support vector machine(LSTSVM)generates two nonparallel hyperplanes directly by solving two systems of linear equations instead of a pair of quadratic programming problems(QPPs),which makes LSTSVM much faster than the original *** the standard LSTSVM adopting quadratic loss measured by the minimal distance is sensitive to noise and unstable to *** overcome this problem,the expectile distance is taken into consideration to measure the margin between classes and LSTSVM with asymmetric squared loss(aLSTSVM)is *** to the original LSTSVM with the quadratic loss,the proposed aLSTSVM not only has comparable computational accuracy,but also performs good properties such as noise insensitivity,scatter minimization and re-sampling *** experiments on synthetic datasets,normally distributed clustered(NDC)datasets and University of California,Irvine(UCI)datasets with different noises confirm the great performance and validity of our proposed algorithm.

关键词： classification least squares twin support vector machine asymmetric loss noise insensitivity

Viral Tools for Neural Circuit Tracing

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Neuroscience Bulletin 2022年第12期38卷 1508-1518页

作者： qing Liu Yang Wu Huadong Wang fan Jia Fuqiang Xu The Brain Cognition and Brain Disease Institute(BCBDI) Shenzhen Key Laboratory of Viral Vectors for BiomedicineShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research InstitutionsNMPA Key Laboratory for Research and Evaluation of Viral Vector Technology in Cell and Gene Therapy Medicinal ProductsShenzhen Key Laboratory of Quality Control Technology for Virus-Based TherapeuticsGuangdong Provincial Medical Products AdministrationShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Key Laboratory of Magnetic Resonance in Biological SystemsWuhan Center for Magnetic ResonanceInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China Center for Excellence in Brain Science and Intelligence Technology Chinese Academy of SciencesShanghai 200031China University of Chinese Academy of Sciences Beijing 100049China

Neural circuits provide an anatomical basis for functional ***,dissecting the structure of neural circuits is essential to understanding how the brain *** neurotropic viruses are important tools for neural circuit tracing with many advantages over non-viral tracers:they allow for anterograde,retrograde,and trans-synaptic delivery of tracers in a cell type-specific,circuit-selective *** this review,we summarize the recent developments in the viral tools for neural circuit tracing,discuss the key principles of using viral tools in neuroscience research,and highlight innovations for developing and optimizing viral tools for neural circuit tracing across diverse animal species,including nonhuman primates.

关键词： Neural circuit Viral tool Anterograde Retrograde Trans-synaptic

Assessment of subgrid-scale models in wall-modeled large-eddy simulations of turbulent channel flows

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Journal of Hydrodynamics 2023年第3期35卷 407-416页

作者： Wei-wen Zhao Fu-chang Zhou Guo-qing fan De-cheng Wan Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Wuhan Second Ship Design and Research Institute Wuhan 430205China

Considering the demanding of grid requirements for high-Reynolds-number wall-bounded flow,the wall-modeled large-eddy simulation(WMLES)is an attractive method to deal with near wall ***,the effect of subgrid-scale(SGS)models for wall-bounded turbulent flow in combination with wall stress models is still *** this paper,turbulent channel flow at Reτ=1000 are numerically simulated by WMLES in conjunction with four different SGS models,i.e.,the wall-adapting local eddy-viscosity model,the dynamic Smagorinsky model,the dynamic SGS kinetic energy model and the dynamic Lagrangian *** mean velocity profiles are compared with the law of the wall,and the velocity fluctuations are compared with direct numerical simulation *** energy spectrum of velocity and wall pressure fluctuations are presented and the role of SGS models on predicting turbulent channel flow with WMLES is discussed.

关键词： Wall-modeled large-eddy simulation(WMLES) subgrid-scale(SGS)model turbulent channel flow energy spectra