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Thick accretion disk configurations around a compact object in the brane-world scenario

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Communications in Theoretical Physics 2023年第11期75卷 76-83页

作者： Yunzhu wei Songbai Chen Jiliang jing Department of Physics Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of EducationInstitute of Interdisciplinary StudiesSynergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangshaHunan 410081China Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China

We have studied the equipotential surfaces of a thick accretion disk around a Casadio-Fabbri-Mazzacurati compact object in the brane-world scenario,which possesses a mass parameter together with a parameterized post-Newtonian(PPN)*** the increase in the PPN parameter,the size of the thick accretion disk decreases,but the corresponding Roche lobe size ***,the larger PPN parameter yields the larger region of existing bound disk structures,where the fluid is not accreted into the central ***,with the increase in the PPN parameter,the position of the Roche lobe gradually moves away from the central compact object,and the thickness of the region enclosed by the Roche lobe decreases near the compact object but increases in the region far from the compact *** results also show that the pressure gradient in the disk decreases with the PPN *** effects of the PPN parameter on the thick accretion disk could help one to further understand compact objects in the brane-world scenario.

关键词： black hole brane world wormhole

A Novel 3D Extended Network Cobalt Paradodecatungstate:Synthesis,Characterization and Crystal Structure of [Co(H_2O)_5]_2[Co(H_2O)_4]_3[H_2W_(12)O_(42)]·11H_2O

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Chinese Journal of Structural Chemistry 2006年第10期25卷 1167-1174页

作者： WANG jing-Ping REN Qing ZHAO Jun-wei NIU jing-Yang Institute of Molecular and Crystal Engineering College of Chemistry and Chemical Engineering Henan University Kaifeng Henan 475001 China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhcu Fujian 350002 China

A cobalt paradodecatungstate [Co（H2O）5]2[Co（H2O）4]3[H2W12O42]·11H2O has been successfully synthesized and structurally characterized by X-ray crystallography. Structure analysis indicates that the title compound is of monoclinic, space group P21/n, with a = 13.449（3）, b = 19.585（4）, c = 13.990（3） °A, = 113.79（3）°, V = 3371.8（12） °A^3, Z = 2, R = 0.0519 and wR = 0.1242. The title compound exhibits a novel 3D extended network structure constructed by interconnecting the paradodecatungstate polyanion [H2W12O42]^10- clusters and cobalt^11 coordination ions.

关键词： paradodecatungstate polyoxometalate cobalt Keggin structure

TEMPORAL AND SPATIAL DISCRETIZATION ON QUASI-3-D GROUNDWATER FINITE ELEMENT MODELLING TO AVOID SPURIOUS OSCILLATION

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Journal of Hydrodynamics 2007年第1期19卷 68-77页

作者： ZHANG Xiang-wei TAKEUCHI Kuniyoshi CHEN jing Department of Planning and Program Ministry of Water Resources of P. R. China Beijing 100053 China Department of Civil and Environmental Engineering Yamanashi University Kofu Japan Institute of Guangzhou Hydraulic Engineering Design and Planning Guangzhou 510000 China

In this article, the fmite element solution of quasi-three-dimensional （quasi-3-D） groundwater flow was mathematically analyzed. The research shows that the spurious oscillation solution to the Finite Element Model （FEM） is the results choosing the small time step △t or the large element size L and using the non-diagonal storage matrix. The mechanism for this phenomenon is explained by the negative weighting factor of implicit part in the discretized equations. To avoid spurious oscillation solution, the criteria on the selection of △t and L for quasi-3-D groundwater flow simulations were identified. An application example of quasi-3-D groundwater flow simulation was presented to verify the criteria. The results indicate that temporal discretization scale has significant impact on the spurious oscillations in the finite-element solutions, and the spurious oscillations can be avoided in solving practical quasi-3-D groundwater flow problems if the criteria are satisfied.

关键词： temporal and spatial discretization spuriousoscillation finite element solution quasi-3-D groundwater flowmodels

Effect of hot/warm roll-forming process on microstructural evolution and mechanical properties of local thickened U-rib for orthotropic steel deck

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Journal of Iron and Steel Research International 2017年第3期24卷 335-342页

作者： Xue-feng Peng jing Liu jing-tao Han Dong-bin wei School of Materials Science and Engineering University of Science and Technology Beijing School of Electrical Mechanical and Mechatronic SystemsFaculty of Engineering and Information TechnologyUniversity of Technology Sydney

To improve the strength-toughness of traditional U-rib（ TUR） and solve the problem of insufficient penetration between TUR and deckplate,a new local thickened U-rib（ LTUR） has been proposed to improve the fatigue resistance of the weld joint under the premise of not increasing thickness and strength of the TUR material. And a hot /warm roll-forming process（ RFP） adopting partially induction heating to 700- 1 000℃ was carried out to fabricate LTUR. The deformation behaviors in the forming process and microstructure of LTUR have been *** properties and fracture mechanism of the LTUR after hot / warm RFP have been systematically discussed. Moreover,the results are compared with those obtained in cold RFP. Mechanical properties of the LTUR deformed above the critical transformation temperature（ A_（c3）） show high performance characteristics with marked fatigue resistance and superior toughness. Upon increasing the heating temperature from 700 to 900 ℃,the initial coarse ferrite-pearlite structure transform into equiaxed ultrafine ferrite（ 1- 3 μm） and precipitates such as（ Nb,Ti）（ C,N） are uniformly distributed in the matrix. The average dislocation density of the specimens after hot rollforming at heating temperature of 900 ℃ decreases dramatically compared with those of the specimens subjected to the cold RFP. Furthermore,a typical characteristic of ductile fracture mechanism and the high impact energy are more convinced that the specimens deformed above 900 ℃ have obtained an optimal combination of strength and toughness.

关键词： Orthotropic steel deck Local thickened U-rib Hot roll-forming process Warm roll-forming process Microstructural evolution Deformation behavior

Patent analysis provides insights into the history of cotton molecular breeding worldwide over the last 50 years

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Journal of Integrative Agriculture 2019年第3期18卷 539-552页

作者： HE wei ZHAO Hui-min YANG Xiao-wei ZHANG Rui WANG jing-jing Agricultural Information Institute Chinese Academy of Agricultural SciencesBeijing 100081P.R.China Biotechnology Research Institute Chinese Academy of Agricultural SciencesBeijing 100081P.R.China

Cotton is a globally important natural fiber and oilseed crop of crucial economic significance. Molecular breeding has become a dominant method of cotton cultivation because it allows for a shorter breeding period and directional selection of high quality genes. Patent data are key resources and are the core competitiveness of agricultural development, as the world's largest and most reliable source of technical information. However, little attention has been paid to patent analysis of cotton molecular breeding. This study uses bibliometric analysis methodology and technical classification indexing to reveal global development trends of cotton molecular breeding, based on patents by retrieval methods and expert screening. The annual number of patents, the life-cycle of patent-based technology, patent portfolios of primary countries, and main patentees, as well as technical distribution of patents, were analyzed in this study. In addition, this study put emphasis on the comparative analysis of two important patentees through patent roadmaps based on the relationship among patent citations. Finally, in order to understand the trend of new molecular breeding technology, patents related to clustered regularly interspaced short palindromic repeats(CRISPR), RNA interference(RNAi), and gene chip were also analyzed, all of which apply to cotton but also to other crops. Results in this paper can provide references for cotton molecular breeding researchers and relevant management departments.

关键词： cotton molecular breeding patent analysis patent roadmap CRISPR RNAi gene chip

Experimental study on pressure and aeration characteristics in stepped chute flows

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Science China(Technological Sciences) 2015年第4期58卷 720-726页

作者： XU wei Lin LUO Shu jing ZHENG Qiu Wen LUO jing State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University

The free flow on the step surfaces has received much attention for its representative body type,flow structure,water-air two phase flow,cavitation,and many complex *** experiments about the time-averaged pressure and aeration concentration distribution on the step surface show that the vertical plane of steps will inevitably experience negative pressure,which must rely on adequate aeration concentration to avoid cavitation ***,the self-aerated flow at the head section has a relatively low aeration concentration,and the concentration of the entire steps decreases with the increasing of weir head,the minimum appears in the vicinity of the corner,and the location is close to the minimum ***,it is necessary to set aerator in the upstream end of the step surfaces to avoid cavitation damage.

关键词： stepped spillway time-averaged pressure aerated flow cavitation erosion

Nanoscale zero-valent iron integrated with bioreactor for recalcitrant antimony-Congo red dyeing wastewater treatment

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Progress in Natural Science:Materials International 2023年第5期33卷 569-574页

作者： jing Liu Airong Liu Yi wei Jiahui Fu wei-xian Zhang College of Environmental Science and Engineering Tongji University State Key Laboratory for Pollution Control and Resource Reuse

Antimony(Sb) and recalcitrant organic dyes often coexist in dyeing wastewater, and the simultaneous removal of Sb and dyes has been a challenge for traditional biological method in the treatment of Sb-dyeing *** zero-valent iron(n ZVI) is particularly suitable for separating heavy metals and enhancing the biodegradability of recalcitrant organic compounds. Herein, n ZVI is integrated with bioreactors(n ZVI-bio system) to achieve enhanced removal of Sb and degradation of Congo red(CR) in wastewater. The n ZVI-bio system achieves a reduction in Sb levels from 2.5 g L-1to 0.064 mg L-1, with a color removal efficiency of up to 98.60 % and a reduction in COD from 167 mg L-1to 55 mg L-1. The excellent performance is mainly attributed to n ZVI pretreatment, which removes Sb and degrades CR into smaller and more biodegradable organic compounds,providing favorable environmental conditions for the subsequent biotreatment system. This suggests that integrated n ZVI-bio system has potential for the treatment of complex wastewater containing heavy metals and recalcitrant organic dyes.

关键词： Nanoscale zero-valent iron Biotreatment Antimony Congo red nZVI-bio system

Epigenetic regulation of macrophages: from homeostasis maintenance to host defense

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Cellular & Molecular Immunology 2020年第1期17卷 36-49页

作者： Siyuan Chen jing Yang Yuquan wei Xiawei wei Laboratory of Aging Research and Cancer Drug Target State Key Laboratory of BiotherapyNational Clinical Research Center for GeriatricsWest China HospitalSichuan UniversityNo.17Block 3Southern Renmin Road610041 ChengduSichuanPR China

Macrophages are crucial members of the innate immune response and important *** differentiation and activation of macrophages require the timely regulation of gene expression,which depends on the interaction of a variety of factors,including transcription factors and epigenetic *** changes also give macrophages the ability to switch rapidly between cellular programs,indicating the ability of epigenetic mechanisms to affect phenotype *** this review,we focus on key epigenetic events associated with macrophage fate,highlighting events related to the maintenance of tissue homeostasis,responses to different stimuli and the formation of innate immune *** understanding of the epigenetic regulation of macrophages will be helpful for maintaining tissue integrity,preventing chronic inflammatory diseases and developing therapies to enhance host defense.

关键词： Macrophage Epigenetics Polarization Immune memory

Selective hydrogenation of 4-nitrostyrene to 4-nitroethylbenzene catalyzed by Pd@Ru core–shell nanocubes

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Rare Metals 2022年第4期41卷 1189-1194页

作者： jing-jing Fang Qi-Ming Liu Xiong-Wu Kang Shao-wei Chen New Energy Technology Institute School of Environment and EnergySouth China University of TechnologyGuangzhou 510006China Department of Chemistry and Biochemistry University of CaliforniaCA 95064USA

It is a challenge to selectively hydrogenate 4-nitrostyrene to 4-nitroethylbenzene,due to the similar energy barrier of hydrogenation of the nitro and vinyl ***,we demonstrate that such selective hydrogenation can be achieved by Pd@Ru core–shell nanocubes that are pre-pared by epitaxial growth of a face-centered cubic Ru shell on Pd *** core–shell structure of Pd@Ru nanocubes is conflrmed by transmission electron microscopy,X-ray diffraction spectroscopy,and elemental mapping *** is found that the electronic structure and hence the catalytic activity of the Pd@Ru nanocubes can be readily modulated by the Ru shell *** is manifested in electrochemical CO stripping measurements where a decrease of CO adsorption energy is observed on Pd@Ru nanocubes with the increase of the Ru shell *** from this study suggest that deliberate structural engineering can be exploited to prepare bimetallic core–shell nanostructures for highly active and selective hydrogenation of organic molecules with multi-functional moieties.

关键词： hydrogenation styrene benzene