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Theoretical analysis and numerical simulation of acoustic waves in gas hydrate-bearing sediments

Chinese Physics B 2021年第2期30卷 344-354页

作者： Lin Liu xiu-Mei Zhang xiu-ming wang State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100149China Beijing Engineering Research Center of Sea Deep Drilling and Exploration Institute of AcousticsChinese Academy of SciencesBeijing 100190China

Based on Carcione-Leclaire model,the time-splitting high-order staggered-grid finite-difference algorithm is proposed and constructed for understanding wave propagation mechanisms in gas hydrate-bearing *** compressional waves and two shear waves,as well as their energy distributions are investigated in *** particular,the influences of the friction coefficient between solid grains and gas hydrate and the viscosity of pore fluid on wave propagation are *** results show that our proposed numerical simulation algorithm proposed in this paper can effectively solve the problem of stiffness in the velocity-stress equations and suppress the grid dispersion,resulting in higher accuracy compared with the result of the Fourier pseudospectral method used by *** excitation mechanisms of the five wave modes are clearly revealed by the results of ***,it is pointed that,the wave diffusion of the second kind of compressional and shear waves is influenced by the friction coefficient between solid grains and gas hydrate,while the diffusion of the third compressional wave is controlled by the fluid ***,two fluid-solid(gas-hydrate formation)models are constructed to study the mode conversion of various *** results show that the reflection,transmission,and transformation of various waves occur on the interface,forming a very complicated wave field,and the energy distribution of various converted waves in different phases is *** is demonstrated from our studies that,the unconventional waves,such as the second and third kinds of compressional waves may be converted into conventional waves on an *** propagation mechanisms provide a concrete wave attenuation explanation in inhomogeneous media.

关键词： gas hydrate-bearing sediments Carcione-Leclaire model time-splitting staggered-grid finite-difference slow-wave characteristics

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Response analyses on the drill-string channel for logging while drilling telemetry

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Petroleum Science 2023年第5期20卷 2796-2808页

作者： Ao-Song Zhao Xiao He Hao Chen xiu-ming wang State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China Beijing Engineering Research Center of Sea Deep Drilling and Exploration Institute of AcousticsChinese Academy of SciencesBeijing100190China

Downhole acoustic telemetry(DAT),using a long drill string with periodical structures as the channel,is a prospective technology for improving the transmission rate of logging while drilling(LWD)*** studies only focused on the acoustic property of a free drill string and neglected the coupling between pipes and fluid-filled *** addition to the drill-string waves,a series of fluid waves are recorded in the DAT channel,which has not been investigated *** channel characteristics result in lower transmission rates and stability than ***,a more realistic channel model is needed considering the fluid-filled *** this paper,we propose a hybrid modeling method to investigate the response characteristics of the DAT *** combining the axial wavenumbers and excitation functions of mode waves in radially layered LWD structures,the channel model is approximated to the 1-D propagation,which considers transmission,reflection,and interconversion of the drillstring and fluid *** proposed 1-D approximation has been well validated by comparing the 2-D finite-difference *** is revealed that the transmitted and converted fluid waves interfere with the drill-string wave,which characterizes the DAT channel as a particular coherent multi-path *** a fluid-filled borehole surrounds the drill string,the channel responses exhibit considerable delay as well as strong frequency selectivity in amplitude and *** new findings suggest that the complexity of the channel response has been underestimated in the past,and therefore channel measurements on the ground are *** address these channel characteristics,we apply a noncoherent demodulation *** transmission rate for synthetic data reaches 15 bps in a 94.5 m long channel,indicating that the acoustic telemetry is promising to break the low-speed limitation of mud-pulse telemetry.

关键词： Logging while drilling Borehole geophysics Downhole acoustic telemetry Channel modeling Frequency selectivity

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Exponential Stability for the Compressible Navier-Stokes Equations

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Chinese Quarterly Journal of Mathematics 2005年第3期20卷 296-300页

作者： QIN Yu-ming wang xiu-qin College of Mathematics and Information Science Henan University Kaifeng 475001 China

We establish the exponential stability of global solutions and C0-semigroup for the compressible *** equations of a viscous polytropic ideal gas in both bounded domain in R^1 and bounded annular domains in R^n （n=2,3）.

关键词： C0-semigroup exponentially stable bounded annular domains

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Identification and Validation of Single Nucleotide Polymorphisms in Poplar Using Publicly Expressed Sequence Tags

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Journal of Integrative Plant Biology 2005年第12期47卷 1493-1499页

作者： Bo ZHANG Yan ZHOU Liang ZHANG Qiang ZHUGE ming-xiu wang Min-Ren HUANG Forest Genetics and Gene Engineering Laboratory Nanjing Forestry University Nanjing 210037 China Genomics and Bioinformatics Institute Hangzhou 310008 China

By using assembled expressed sequence tags （ESTs） from 14 different eDNA libraries that contain 84 132 sequences reads, 556 Populus candidate single nucleotide polymorphisms （SNPs） were identified. Because traces were not available from dbEST （http：//***/dbEST/***）, stringent filters were used to identify reliable candidate SNPs. Sequences analysis indicated that the main types of substitutions among candidate SNPs were A/G and T/C transitions, which accounted for 22.0% and 30.8%, respectively. One hundred and ten candidate SNPs were tested. As a result, 38 candidate SNPs were confirmed by directed sequencing of PCR products amplified from six different individuals. Thirteen new SNPs in intron regions were found and multiple SNPs were found to be located in both intron and exon regions of four contigs. Heterozygosis was found in all 47 candidate sites and five SNP sites were heterozygous in all six samples. This is the first report of SNP identification in a tree species which reveals that assembled ESTs from multiple libraries of the public database may provide a rich source of comparative sequences for an SNP search in the poplar genome.

关键词： expressed sequence tag poplar single nucleotide polymorphism.

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Generalized collar waves in acoustic logging while drilling

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Chinese Physics B 2016年第12期25卷 118-120页

作者：王秀明何晓张秀梅 State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of Sciences

Tool waves, also named collar waves, propagating along the drill collars in acoustic logging while drilling （ALWD）, strongly interfere with the needed P- and S-waves of a penetrated formation, which is a key issue in picking up formation P- and S-wave velocities. Previous studies on physical insulation for the collar waves designed on the collar between the source and the receiver sections did not bring to a satisfactory solution. In this paper, we investigate the propagation features of collar waves in different models. It is confirmed that there exists an indirect collar wave in the synthetic full waves due to the coupling between the drill collar and the borehole, even there is a perfect isolator between the source and the receiver. The direct collar waves propagating all along the tool and the indirect ones produced by echoes from the borehole wall are summarized as the generalized collar waves. Further analyses show that the indirect collar waves could be relatively strong in the full wave data. This is why the collar waves cannot be eliminated with satisfactory effect in many cases by designing the physical isolators carved on the tool.

关键词： acoustic logging while drilling borehole wave propagation generalized collar waves indirectcollar waves

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Sequential enantioselective Ugi-4CR/post-Ugi transformation strategy:a precise construction of structurally diverse azaspiro polycyclic scaffolds

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Science China Chemistry 2024年第2期67卷 576-586页

作者： Xiao-Bao Wu Jun-xiu Shi Yi-ming Ou Hua-Jie Jiang Yi-Jun Fang Qi-ming wang Quan Gao Jie Yu Department of Applied Chemistry Anhui Province Engineering Laboratory for Green Pesticide Development and ApplicationAnhui Province Key Laboratory of Crop Integrated Pest ManagementAnhui Agricultural UniversityHefei230036China

A privileged strategy has been developed for the precise construction of enantioenriched azaspiro polycyclic *** diverse azaspiro polycycles bearing multiple contiguous stereocenters are obtained with excellent results(up to 99:1 e.r.,>95:5 d.r.) via sequential enantioselective four-component Ugi reactions/post-Ugi transformations with substrates containing prerequisite functional groups in the presence of anionic stereogenic-at-cobalt(Ⅲ) complexes.

关键词： asymmetric catalysis post-Ugi transformation anionic stereogenic-at-cobalt(Ⅲ)complex azaspiro polycyclic scaffold one-pot synthesis

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Pseudorabies virus manipulates mitochondrial tryptophanyl-tRNA synthetase 2 for viral replication

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Virologica Sinica 2024年第3期39卷 403-413页

作者： xiu-Qing Li Meng-Pan Cai ming-Yang wang Bo-Wen Shi Guo-Yu Yang Jiang wang Bei-Bei Chu Sheng-Li ming College of Veterinary Medicine Henan Agricultural UniversityZhengzhou 450046China Key Laboratory of Animal Biochemistry and Nutrition Ministry of Agriculture and Rural AffairsZhengzhou 450046China Key Laboratory of Veterinary Biotechnology of Henan Province Henan Agricultural UniversityZhengzhou 450046China Longhu Advanced Immunization Laboratory Zhengzhou 450046China International Joint Research Center of National Animal Immunology Henan Agricultural UniversityZhengzhou 450046China Ministry of Education Key Laboratory for Animal Pathogens and Biosafety Zhengzhou 450046China School of Basic Medicine Chongqing Medical UniversityChongqing 400016China

The pseudorabies virus(PRV)is identified as a double-helical DNA virus responsible for causing Aujeszky's disease,which results in considerable economic impacts *** enzyme tryptophanyl-tRNA synthetase 2(WARS2),a mitochondrial protein involved in protein synthesis,is recognized for its broad expression and vital role in the translation *** findings of our study showed an increase in both mRNA and protein levels of WARS2 following PRV infection in both cell cultures and animal *** WARS2 expression via RNA interference in PK-15 cells led to a reduction in PRV infection rates,whereas enhancing WARS2 expression resulted in increased infection ***,the activation of WARS2 in response to PRV was found to be reliant on the cGAS/STING/TBK1/IRF3 signaling pathway and the interferon-alpha receptor-1,highlighting its regulation via the type I interferon signaling *** analysis revealed that reducing WARS2 levels hindered PRV's ability to promote protein and lipid *** research provides novel evidence that WARS2 facilitates PRV infection through its management of protein and lipid levels,presenting new avenues for developing preventative and therapeutic measures against PRV infections.

关键词： Pseudorabies virus WARS2 Innate immunity Protein synthesis Lipid synthesis

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Dynamic Analysis of A Deepwater Drilling Riser with A New Hang-off System

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China Ocean Engineering 2024年第1期38卷 29-41页

作者： LI Yan-wei LIU xiu-quan wang Jin-long CHEN Guo-ming CHANG Yuan-jiang SHENG Lei-xiang Centre for Offshore Engineering and Safety Technology China University of PetroleumQingdao 266580China National Engineering Laboratory of Offshore Geophysical and Exploration Equipment China University of PetroleumQingdao 266580China China CNOOC Research Institute Co. Ltd.Beijing 100028China

The safety of risers in hang-off states is a vital challenge in offshore oil and gas engineering.A new hang-off system installed on top of risers is proposed for improving the security of *** approach leads to a challenging problem:coupling the dynamics of risers with a new hang-off system combined with multiple structures and complex *** accurately analyze the dynamic responses of the coupled system,a coupled dynamic model is established based on the Euler-Bernoulli beam-column theory and penalty function method.A comprehensive analysis method is proposed for coupled dynamic analysis by combining the finite element method and the Newmarkβ*** analysis program is also developed in MATLAB for dynamic *** simulation results show that the dynamic performances of the risers at the top part are significantly improved by the new hang-off system,especially the novel design,which includes the centralizer and articulation *** bending moment and lateral deformation of the risers at the top part decrease,while the hang-off joint experiences a great bending moment at the bottom of the lateral restraint area which requires particular attention in design and *** platform navigation speed range under the safety limits of risers expands with the new hang-off system in use.

关键词： deepwater drilling riser new hang-off system dynamic analysis finite element method penalty function method

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Possibilities for the synthesis of superheavy element Z=121 in fusion reactions

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Nuclear Science and Techniques 2024年第6期35卷 90-100页

作者： ming-Hao Zhang Yu-Hai Zhang Ying Zou xiu-xiu Yang Gen Zhang Feng-Shou Zhang The Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China School of Physical Science and Technology Guangxi UniversityNanning 530004China National Laboratory of Heavy Ion Accelerator of Lanzhou Center of Theoretical Nuclear PhysicsLanzhou 730000China

Based on the dinuclear system model,the calculated evaporation residue cross sections matched well with the current experimental *** synthesis of superheavy elements Z=121 was systematically studied through combinations of stable projectiles with Z=21-30 and targets with half-lives exceeding 50 *** influence of mass asymmetry and isotopic dependence on the projectile and target nuclei was investigated in *** reactions^(254)Es(^(46)Ti,3n)^(297)121 and^(252)Es(^(46)Ti,3n)^(295)121 were found to be experimentally feasible for synthesizing superheavy element Z=121,with maximal evaporation residue cross sections of 6.619 and 4.123 fb at 219.9 and 223.9 MeV,respectively.

关键词： Superheavy nuclei Dinuclear system model Fusion reaction Evaporation residue cross section

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Morphology Study for GeV Emission of Nearby Supernova Remnant G332.5-5.6

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Research in Astronomy and Astrophysics 2024年第4期24卷 134-140页

作者： ming-Hong Luo Qing-Wen Tang xiu-Rong Mo Department of Physics School of Physics and Materials ScienceNanchang UniversityNanchang 330031China

A spatial template is important to study nearby supernova remnants(SNRs).For SNR G332.5-5.6,we report a Gaussian disk with a radius of about 1°.06 to be a potential good spatial model in the γ-ray *** this new Gaussian disk,its GeV lightcurve shows a significant variability of about seven *** γ-ray observations of this SNR could be explained well either by a leptonic model or a hadronic model,in which a flat spectrum for the ejected electrons/protons is required.

关键词： ISM:supernova remnants gamma rays:ISM

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