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Seismic rock physical modelling for gas hydrate-bearing sediments

Science China Earth Sciences 2018年第9期61卷 1261-1278页

作者： Xinxin LIU Xingyao YIN Xiwu luan Key Laboratory of Gas Hydrate Ministry of Land and Resources Qingdao Institute of Marine Geology Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology School of Geosciences China University of Petroleum (East China)

There are ambiguities and uncertainties in the recognition of gas hydrate seismic reflections and in quantitative predictions of physical information of natural gas hydrate reservoirs from seismic data. Rock physical modelling is a bridge that transforms the seismic information of geophysical observations into physical information, but traditional rock physics models lack descriptions of reservoir micro-structures and pore-filling materials. Considering the mineral compositions and pore microstructures of gas hydrates, we built rock physical models for load-bearing and pore-filling gas hydrate-bearing sediments,describe the mineral compositions, pore connectivity and pore shape using effective media theory, calculated the shear properties of pore-filling gas hydrates using Patchy saturation theory and Generalized Gassmann theory, and then revealed the quantitative relation between the elastic parameters and physical parameters for gas hydrate-bearing sediments. The numerical modelling results have shown that the ratios of P-wave and S-wave velocities decrease with hydrate saturation, the P-wave and S-wave velocities of load-bearing gas hydrate-bearing sediments are more sensitive to hydrate saturation, sensitivity is higher with narrower pores, and the ratios of the P-wave and S-wave velocities of pore-filling gas hydrate-bearing sediments are more sensitive to shear properties of hydrates at higher hydrate saturations. Theoretical analysis and practical application results showed that the rock physical models in this paper can be used to calculate the quantitative relation between macro elastic properties and micro physical properties of gas hydrate-bearing sediments, offer shear velocity information lacking in well logging, determine elastic parameters that have more effective indicating abilities, obtain physical parameters such as hydrate saturation and pore aspect ratios, and provide a theoretical basis and practical guidance for gas hydrate quantitative predic

关键词： Gas hydrate Rock physical modelling Load-bearing gas hydrate Pore-filling gas hydrate Shear modulus Pore micro-structure Elastic parameter

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Investigation on N-doped FZ-Si Crystals by IR Absorption Spectrum

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Rare Metals 1989年第3期9卷 46-50页

作者： luan, Hongfa Liang, Junwu Acad Sinica China

N-doped FZ-Si crystals and N-doped NTD FZ-Si crystals and their annealing behavior have been studied by IR spectrum. Two models of nitrogen configuration, nearly substitutional nitrogen and interstitial nitrogen pair,... 详细信息

关键词： Crystals Atomic Structure Molecules Vibrations Nitrogen Effects Spectroscopy, Absorption Applications Spectroscopy, Infrared Applications

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On Fixed Point and Almost Fixed Point Problems of Lower Semicontinuous Type Multivalued Mappings

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Acta Mathematica Sinica,English Series 2005年第5期21卷 1027-1034页

作者： Liang Yu luan Xian WU Institute of Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 P. R. China Department of Mathematics Yunnan Normal University Kunming 650092 P. R. China

In the present paper, some new almost fixed point theorems and fixed point theorems for lower semicontinuous type multivalued mappings are obtained in metrizable H-spaces.

关键词： Lc.-metric space H-space Lower semicontinuous multivalued mapping Locally-uniformly weak lower semicontinuous multivalued mapping

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Periodic Solutions of Nonautonomous Second Order Hamiltonian Systems

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Acta Mathematica Sinica,English Series 2005年第4期21卷 685-690页

作者： Shi Xia luan An Min MAO Department of Mathematics Qufu Normal University Qufu 273165. P. R. China Institute of Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences. Beijing 100080. P. R. China

In this paper, we develop the local linking theorem given by Li and Willein by replacing the Palais-Smale condition with a Cerami one, and apply it to the study of the existence of periodic solutions of the nonautonomous second order Hamiltonian systems （H） ü＋A（t）u＋∨V（t, u）=0, u∈R^N, t∈R. We handle the case of superquadratic nonlinearities which differ from those used previously. Our results extend the theorems given by Li and Willem.

关键词： Non-autonomous Hamiltonian systems Periodic solutions Local linking Critical point theory Variational method

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Cartoon capture by key-frame based contour tracking

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第1期12卷 36-43页

作者： Chun-luan ZHOU Jun XIAO Institute of Artificial Intelligence School of Computer Science and Technology Zhejiang Univetrsity Hangzhou 310027 China

Traditional cartoons have been widely used in entertainment,education,and ***,a large amount of cartoon data is *** this paper,we propose a new technique for capturing the motion of a character in an existing cartoon *** technique tracks the contours of the cartoon character in the sequence,and key frames are used to guide the *** model contour tracking as a space-time optimization problem in which an energy function including both temporal and spatial constraints is ***,the user labels the contours of the character on the key ***,the contours on the intermediate frames are tracked by minimizing the energy *** user may need to interactively adjust the tracking result and restart the optimization process to refine the ***,an edge snapping algorithm is applied to make the tracking result more *** show that our technique works effectively.

关键词： Cartoon reuse Cartoon capture Key frame Contour tracking

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[3+2]Cycloaddition of Vinyl Cyclopropane and Hydroxylamines via Isocynate Intermediate toγ-Lactams

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Chinese Journal of Chemistry 2023年第16期41卷 1937-1942页

作者： Xiaobing Huang Jingxun Yu Xinjun luan Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemitry&Materials ScienceNorthwest UniversityXi'anShaanxi 710127China

Comprehensive Summary A general and efficient strategy for the synthesis ofγ-lactams has been *** hydroxylamines form Lossen rearrangement products of electron-deficient group migration with base and then undergo[3+2]cycloaddition reaction with vinyl cyclopropane,which could be performed with broad substrate scope,excellent functional group tolerance and high efficiency to produce the desired *** also allowed further modification to other derivatives of theseγ-lactams.

关键词： γ-Lactams Hydroxylamines VinyI cyclopropane Pd-catalyzed [3+2]cycloaddition Amination Insertion Ring expansion

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Simulation of a Shock Tube with a Small Exit Nozzle

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Journal of Thermal Science 2018年第1期27卷 34-38页

作者： Yigang luan Matthias Olzmann Franco Magagnato Harbin Engineering University HarbinChina Karlsruhe Institute of Technology(KIT) Institute of Physical ChemistryKaiserstrasse 1276131 KarlsruheGermany Karlsruhe Institute of Technology(KIT) Institute of Fluid MechanicsKaiserstrasse 1276131 KarlsruheGermany

Shock tubes are frequently used to rapidly heat up reaction mixtures to study chemical reaction mechanisms and kinetics in the field of combustion chemistry [1]. In the present work, the flow field inside a shock tube with a small nozzle in the end plate has been investigated to support the analysis of reacting chemical mixtures with an attached mass spectrometer and to clarify whether the usual assumptions for the flow field and the related ther- modynamics are fulfilled. In the present work, the details of the flow physics inside the tube and the flow out of the nozzle in the end plate have been investigated. Due to the large differences in the typical length scales and the large pressure ratios of this special device, a very strong numerical stiffness prevails during the simulation process. Second-order ROE numerical schemes have been employed to simulate the flow field inside the shock tube. The simulations were performed with the commercial code ANSYS Fluent [2]. Axial-symmetric boundary conditions are employed to reduce the consumption of CPU time. A density-based transient scheme has been used and vali- dated in terms of accuracy and efficiency. The simulation results for pressure and density are compared with ana- lytical solutions. Numerical results show that a density-based numerical scheme performs better when dealing with shock-tube problems [5]. The flow field near the nozzle is studied in detail, and the effects of the nozzle to pressure and temperature variations inside the tube are invcstigatcd. The results show that this special shock-tube setup can be used to study high-temperature gas-phase chemical reactions with reasonable accuracy.

关键词： CFD shock tube low pressure numerical scheme

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Chitosan Obtained from Cell Wall of Aspergillus Niger Mycelium

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Chemical Research in Chinese Universities 2004年第2期20卷 156-158页

作者： HUANGHui-li LINWen-luan LINJian-ming CollegeofMaterialsScienceandEngineering HuaqiaoUniversityQuanzhouP.R.China

Chitin from cell walls of Aspergillus Niger mycelium was prepared. A new method for the preparation of high deacetylation degree chitosan was studied in a dilute sodium hydroxide solution at a high pressure. The experimental results indicate that the deacetylation degree of the chitosan can reach 80% under the condition of a 5.00 mol/L sodium hydroxide solution at 0.1 MPa of pressure for 1 h. This method shows the advantages of the applications in the industry production and environment protection.

关键词： Aspergillus Niger Chitosan Deacetylation degree

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Challenges in Treatment of Primary Sjogren’s Syndrome and Opportunities for Chinese Medicine

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Chinese Journal of Integrative Medicine 2020年第7期26卷 483-485页

作者： HOU Jia-qi XUE luan Department of Rheumatology and Immunology Yueyang Hospital of Integrated Traditional Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghai(200437)China

Primary Sjogren’s syndrome is a chronic autoimmune disease that can lead to systemic *** present,immunomodulatory agents have not shown good efocacy,many patients in China seek Chinese medicine *** medicine can comprehensively improve the symptoms of patients through Chinese pattern diagnosis and individualized *** researches are providing scientioc bases for the therapeutic effect of Chinese *** Chinese medicine treatment can be integrated into the conventional management of primary Sjogren’s syndrome.

关键词： primary Sjogren's syndrome immunomodulatory agents Chinese medicine

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Theoretical design for zeolite synthesis

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Science China Chemistry 2022年第9期65卷 1683-1690页

作者： Qinming Wu Huimin luan Feng-Shou Xiao Key Lab of Biomass Chemical Engineering of Ministry of Education College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China Key Lab of Applied Chemistry of Zhejiang Province Department of ChemistryZhejiang UniversityHangzhou 31007China

Zeolites,an important class of microporous crystals,have been widely utilized in the fields of catalysis,ion-exchange,separation,and sorption for a long *** general,zeolites are synthesized in the presence of costly organic templates under hydrothermal conditions by trial-and-error method,which is not only environmentally unfriendly but also *** recent years,novel concepts of design for zeolite synthesis,which are sustainable,cheap,simple,and efficient,have been *** this review,the recent advances in design for zeolite synthesis will be briefly summarized,mainly including the design of organic templates for directing the formation of zeolites,design of organotemplate-free route for zeolite synthesis,design of solvent-free strategy for zeolite synthesis,design for novel interzeolite transformation,and targeted control of zeolite *** review might be helpful for developing sustainable routes for targeted synthesis of zeolites in the future.

关键词： zeolite organic template organotemplate-free solvent-free interzeolite transformation morphology control

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