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Chinese Chemical Letters 2006年第8期17卷 1077-1080页

作者： Hua Lin XIE Xi Du NIE You gen tang Department of Chemistry Hunan Institute of Technology Hengyang 421008 School of Chemistry and Chemical Engineering Central south university Changsha 410083

An analytical method using high resolution inductively coupled plasma mass spectrometry （HR-ICP-MS） for rapid simultaneous determination of Be, Mg, Al, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, As, Se, Mo, Ag, Cd, Sn, Sb, Ba, Pt, Au and Pb in high purity cobalt was described. Sample digestions were performed in closed microwave vessels using HNO3 and HCl. The matrix effects due to the presence of excess HCl and Co were evaluated. The usefulness of high mass resolution for overcoming some spectral interference was demonstrated. The optimum conditions for the determination was tested and discussed. Correction for matrix effects, Sc, Rh and Bi were used as internal standards. The detection limits is 0.003-0.57 μg/g, the recovery ratio is 92.2%-111.2%, and the RSD is less than 3.6%. The method is accurate, quick and convenient. It has been applied to the determination of trace impurities in high purity cobalt with satisfactory results.

关键词： High resolution inductively coupled plasma mass spectrometry high purity cobalt,trace impurities matrix effect spectral interference internal standards.

A Possible Experimental Test on Five-Dimensional Gravitation Theory of Complex Field

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Communications in Theoretical Physics 2008年第2期49卷 382-384页

作者： WANG Yong-Jiu LI Ai-gen tang Zhi-Ming Institute of Physics Hunan Normal University Changsha 410081 China

By appropriately choosing additional dimensions of space-time, the mass spectrum of mesons is obtained, and the calculated results agree with the experimental data.

关键词： gravitation complex field experiment inspect

LiNi_(0.7)Co_(0.15)Mn_(0.15)O_2 microspheres as high-performance cathode materials for lithium-ion batteries

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Rare Metals 2014年第5期33卷 608-614页

作者： Zhou-Guang Lu Xin-Xin Tan You-gen tang Ke-Chao Zhou Key Laboratory of Powder Metallurgy Central South University College of Chemical & Chemical Engineering Central South University

Advanced uniform LiNi0.7Co0.15Mn0.15O2 microspheres were successfully synthesized and examined as cathode materials for lithium-ion batteries. The structure,morphology, and electrochemical performance of LiNi0.7-Co0.15Mn0.15O2 calcined at different temperatures ranging from 650 to 900 °C were systematically investigated. The XRD results show that the material has a well-ordered layered structure with small amount of cation mixing. A distinct spherical morphology of the obtained powders prepared at different temperatures can be seen from the SEM images. The as-synthesized LiNi0.7Co0.15Mn0.15O2 powders have a very high-tap density of about 2.37 g·cm^-3. Among all the samples,the sample calcined at 750 °C exhibits the best electrochemical performance with an initial discharge capacity of185.2 mAh·g^-1（3.0–4.3 V, 0.2C rate） and capacity retention〉94.77 %***,thismaterialshowshighspecific capacity and good cycling stability. The LiNi0.7-Co0.15Mn0.15O2 microspheres with high-specific capacity and high-tap density are promising to use as cathode materials for next-generation high-energy-density lithium-ion batteries.

关键词： Lithium-ion batteries High-energy density Microspheres LiNi0.7Co0.15Mn0.15O2 Co-precipitation method

Petrophysical parameters inversion for heavy oil reservoir based on a laboratory-calibrated frequency-variant rock-physics model

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Petroleum Science 2023年第6期20卷 3400-3410页

作者： Xu Han Shang-Xu Wang Zheng-Yu-Cheng Zhang Hao-Jie Liu Guo-Hua Wei gen-Yang tang CNPC Key Laboratory of Geophysical Prospecting China University of Petroleum(Beijing)Beijing102249China Engineering Research Center of the Ministry of Education for Exploration and Development of Complex Oil and Gas Reservoirs China University of Petroleum(Beijing)Beijing102249China Shengli Oilfield Geophysical Exploration Research Institute SinopecDongying257000ShandongChina

Heavy oil has high density and viscosity, and exhibits viscoelasticity. Gassmann's theory is not suitable for materials saturated with viscoelastic fluids. Directly applying such model leads to unreliable results for seismic inversion of heavy oil reservoir. To describe the viscoelastic behavior of heavy oil, we modeled the elastic properties of heavy oil with varying viscosity and frequency using the Cole-Cole-Maxwell (CCM) model. Then, we used a CCoherent Potential Approximation (CPA) instead of the Gassmann equations to account for the fluid effect, by extending the single-phase fluid condition to two-phase fluid (heavy oil and water) condition, so that partial saturation of heavy oil can be considered. This rock physics model establishes the relationship between the elastic modulus of reservoir rock and viscosity, frequency and saturation. The viscosity of the heavy oil and the elastic moduli and porosity of typical reservoir rock samples were measured in laboratory, which were used for calibration of the rock physics model. The well-calibrated frequency-variant CPA model was applied to the prediction of the P- and S-wave velocities in the seismic frequency range (1–100 Hz) and the inversion of petrophysical parameters for a heavy oil reservoir. The pre-stack inversion results of elastic parameters are improved compared with those results using the CPA model in the sonic logging frequency (∼10 kHz), or conventional rock physics model such as the Xu-Payne model. In addition, the inversion of the porosity of the reservoir was conducted with the simulated annealing method, and the result fits reasonably well with the logging curve and depicts the location of the heavy oil reservoir on the time slice. The application of the laboratory-calibrated CPA model provides better results with the velocity dispersion correction, suggesting the important role of accurate frequency dependent rock physics models in the seismic prediction of heavy oil reservoirs.

关键词： Heavy oil Rock physics Velocity dispersion Pre-stack inversion Reservoir prediction

Modeling the efects of fracture infll on frequency‑dependent anisotropy and AVO response of a fractured porous layer

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Petroleum Science 2021年第3期18卷 758-772页

作者： Yan-Xiao He Xin-Long Li gen-Yang tang Chun-Hui Dong Mo Chen Shang-Xu Wang State Key Laboratory of Petroleum Resources and Prospecting CNPC Key Laboratory of Geophysical ExplorationChina University of Petroleum(Beijing)Beijing 102249China Daqing Oilfeld Exploration and Development Institute Daqing 163000Heilongjiang ProvinceChina

In a fractured porous hydrocarbon reservoir,wave velocities and refections depend on frequency and incident angle.A proper description of the frequency dependence of amplitude variations with ofset(AVO)signatures should allow efects of fracture inflls and attenuation and dispersion of fractured *** novelty of this study lies in the introduction of an improved approach for the investigation of incident-angle and frequency variations-associated refection *** improved AVO modeling method,using a frequency-domain propagator matrix method,is feasible to accurately consider velocity dispersion predicted from frequency-dependent elasticities from a rock physics *** hence,the method is suitable for use in the case of an anisotropic medium with aligned ***,the proposed modeling approach allows the combined contributions of layer thickness,interbedded structure,impedance contrast and interferences to frequency-dependent refection coefcients and,hence,yielding seismograms of a layered model with a dispersive and attenuative *** numerical results show bulk modulus of fracture fuid signifcantly afects anisotropic attenuation,hence causing frequencydependent refection *** implications indicate the study of amplitude versus angle and frequency(AVAF)variations provides insights for better interpretation of refection anomalies and hydrocarbon identifcation in a layered reservoir with vertical transverse isotropy(VTI)dispersive media.

关键词： Seismic anisotropy Fractured media Attenuation and dispersion AVO responses Frequency dependence

A single-cell atlas of mouse olfactory bulb chromatin accessibility

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Journal of genetics and genomics 2021年第2期48卷 147-162页

作者： Yin Chen Xiangning Ding Shiyou Wang Peiwen Ding Zaoxu Xu Jiankang Li Mingyue Wang Rong Xiang Xiaoling Wang Haoyu Wang Qikai Feng Jiaying Qiu Feiyue Wang Zhen Fluang Xingliang Zhang gen tang Shengping tang BGI Education Center University of Chinese Academy of SciencesShenzhen 518083China BGI-Shenzhen Shenzhen 518083China School of Biological Science&Medical Engineering Southeast UniversityNanjing 210096China Southern Center for Biomedical Research and Fujian Key Laboratory of Developmental and Neural Biology College of Life SciencesFujian Normal UniversityFuzhouFujian 350117China Shenzhen Children’s Hospital Shenzhen 518083China Department of Pediatrics the Affiliated Hospital of Guangdong Medical UniversityZhanjiang 524000China Zunyi Medical University ZunyiGuizhou 563099China China Medical University ShenyangLiaoning 110122China

Olfaction,the sense of smell,is a fundamental trait crucial to many *** olfactory bulb(OB)plays pivotal roles in processing and transmitting odor information from the environment to the *** cellular heterogeneity of the mouse OB has been studied using single-cell RNA ***,the epigenetic landscape of the m OB remains mostly ***,we apply single-cell assay for transposaseaccessible chromatin sequencing to profile the genome-wide chromatin accessibility of 9,549 single cells from the m *** on single-cell epigenetic signatures,m OB cells are classified into 21 clusters corresponding to 11 cell *** identify distinct sets of putative regulatory elements specific to each cell cluster from which putative target genes and enriched potential functions are *** addition,the transcription factor motifs enriched in each cell cluster are determined to indicate the developmental fate of each cell *** study provides a valuable epigenetic data set for the m OB at single-cell resolution,and the results can enhance our understanding of regulatory circuits and the therapeutic capacity of the OB at the single-cell level.

关键词： scATAC-seq Mouse olfactory bulb Chromatin accessibility Transcription factor Endogenous retroviral elements Co-embedding analysis

Total Saponins of Panax notoginseng Activate Akt/mTOR Pathway and Exhibit Neuroprotection in vitro and in vivo against Ischemic Damage

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Chinese Journal of Integrative Medicine 2022年第5期28卷 410-418页

作者： PAN Yu-wei WU Dong-ping LIANG Hua-feng tang gen-yun FAN Chun-lin SHI Lei YE Wen-cai LI Man-mei JNU-HKUST Joint Laboratory for Neuroscience and Innovative Drug Research Jinan UniversityGuangzhou(510632)China Department of TCM Preventive Medicine Tianhe District Hospital of Traditional Chinese MedicineGuangzhou(510632)China Institute of Traditional Chinese Medicine and Natural Products Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs ResearchCollege of PharmacyJinan UniversityGuangzhou(510632)China

Objective:To reveal the neuroprotective effect and the underlying mechanisms of a mixture of the main components of Panax notoginseng saponins(TSPN)on cerebral ischemia-reperfusion injury and oxygenglucose deprivation/reoxygenation(OGD/R)of cultured cortical ***:The neuroprotective effect of TSPN was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide(MTT)assay,flow cytometry and live/dead cell *** morphology of dendrites was detected by *** cerebral artery occlusion(MCAO)was developed in rats as a model of cerebral *** neuroprotective effect of TSPN was evaluated by neurological scoring,tail suspension test,2,3,5-triphenyltetrazolium chloride(TTC)and Nissl *** blot analysis,immunohistochemistry and immunofluorescence were used to measure the changes in the Akt/mammalian target of rapamycin(mTOR)signaling ***:MTT showed that TSPN(50,25 and 12.5μg/m L)protected cortical neurons after OGD/R treatment(P<0.01 or P<0.05).Flow cytometry and live/dead cell assays indicated that 25μg/m L TSPN decreased neuronal apoptosis(P<0.05),and immunofluorescence showed that 25μg/m L TSPN restored the dendritic morphology of damaged neurons(P<0.05).Moreover,12.5μg/m L TSPN downregulated the expression of Beclin-1,Cleaved-caspase 3 and LC3 B-Ⅱ/LC3 B-Ⅰ,and upregulated the levels of phosphorylated(p)-Akt and p-mTOR(P<0.01 or P<0.05).In the MCAO model,50μg/m L TSPN improved defective neurological behavior and reduced infarct volume(P<0.05).Moreover,the expression of Beclin-1 and LC3 B in cerebral ischemic penumbra was downregulated after 50μg/m L TSPN treatment,whereas the p-mTOR level was upregulated(P<0.05 or P<0.01).Conclusions:TSPN promoted neuronal survival and protected dendrite integrity after OGD/R and had a potential therapeutic effect by alleviating neurological deficits and reversing neuronal *** promoted p-mTOR and inhibited Beclin-1 to alleviate ischemic damage,

关键词： total saponins of Panax notoginseng oxygen-glucose deprivation and reoxygenation neuroprotection ischemia-reperfusion Akt/mTOR pathway Chinese medicine

A seismic elastic moduli module for the measurements of low-frequency wave dispersion and attenuation of fluid-saturated rocks under different pressures

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Petroleum Science 2024年第1期21卷 162-181页

作者： Yan-Xiao He Shang-Xu Wang gen-Yang tang Chao Sun Hong-Bing Li San-Yi Yuan Xian Wei Li-Deng Gan Xiao-Feng Dai Qiang Ge Peng-Peng Wei Hui-Qing Zhang National Key Laboratory of Petroleum Resources and Engineering CNPC Key Lab of Geophysical ExplorationCollege of GeophysicsChina University of Petroleum(Beijing)Beijing102249China School of Resources and Geosciences China University of Mining and TechnologyXuzhou221116JiangsuChina Research Institute of Petroleum Exploration and Development CNPCBeijing100083China Beijing Vocational College of Labour and Social Security Beijing100029China PetroChina Dagang Oilfield Exploration and Development Research Institute CNPCTianjin300280China

Knowledge about the seismic elastic modulus dispersion,and associated attenuation,in fluid-saturated rocks is essential for better interpretation of seismic observations taken as part of hydrocarbon identification and time-lapse seismic surveillance of both conventional and unconventional reservoir and overburden performances.A Seismic Elastic Moduli Module has been developed,based on the forced-oscillations method,to experimentally investigate the frequency dependence of Young's modulus and Poisson's ratio,as well as the inferred attenuation,of cylindrical samples under different confining pressure *** with three standard samples showed that the measured elastic moduli were consistent with the published data,indicating that the new apparatus can operate reliably over a wide frequency range of f∈[1-2000,10^(6)]*** Young's modulus and Poisson's ratio of the shale and the tight sandstone samples were measured under axial stress oscillations to assess the frequency-and pressure-dependent *** dry condition,both samples appear to be nearly frequency independent,with weak pressure dependence for the shale and significant pressure dependence for the *** particular,it was found that the tight sandstone with complex pore microstructure exhibited apparent dispersion and attenuation under brine or glycerin saturation conditions,the levels of which were strongly influenced by the increased effective *** addition,the measured Young's moduli results were compared with the theoretical predictions from a scaled poroelastic model with a reasonably good agreement,revealing that the combined fluid flow mechanisms at both mesoscopic and microscopic scales possibly responsible for the measured dispersion.

关键词： Low-frequency measurements Dispersion and attenuation Rock physics Fluid flow

Single-cell brain atlas of Parkinson's disease mouse model

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Journal of genetics and genomics 2021年第4期48卷 277-288页

作者： Jixing Zhong gen tang Jiacheng Zhu Weiying Wu Ge Li Xiumei Lin Langchao Liang Chaochao Chai Yuying Zeng Feiyue Wang Lihua Luo Jiankang Li Fang Chen Zhen Huang Xiuqing Zhang Yu Zhang Hongde Liu Xin Qiu Shengping tang Dongsheng Chen School of Biological Science&Medical Engineering Southeast UniversityNanjing 210096China BGI-Shenzhen Shenzhen 518083China Shenzhen Children's Hospital Shenzhen 518083China BGI Education Center University of Chinese Academy of SciencesShenzhen 518083China Department of Neurobiology NHC and CAMS Key Laboratory of Medical NeurobiologySchool of Brain Science and Brian MedicineAnd the MOE Frontier Science Center for Brain Research and Brain-Machine IntegrationZhejiang University School of MedicineHangzhou 310012China Guangdong Provincial Key Laboratory of Laboratory Animals Guangdong Laboratory Animals Monitoring InstituteGuangzhouGuangdong 510663China MGI BGI-ShenzhenShenzhen 518083China Life Science College Fujian Normal UniversityFuzhou 350108China Key Laboratory of Special Marine Bio-resources Sustainable Utilization of Fujian Province Fuzhou 350108China

Parkinson's disease(PD)is a neurodegenerative disease,leading to the impairment of movement *** pathogenesis has been largely investigated,either limited to bulk transcriptomic levels or at certain cell types,which failed to capture the cellular heterogeneity and intrinsic interplays among distinct cell ***,we report the application of single-nucleus RNA-seq on midbrain,striatum,and cerebellum of theα-syn-A53 T mouse,a well-established PD mouse model,and matched controls,generating the first single cell transcriptomic atlas for the PD model mouse brain composed of 46,174 individual ***,we comprehensively depicte the dysfunctions in PD pathology,covering the elevation of NF-k B activity,the alteration of ion channel components,the perturbation of protein homeostasis network,and the dysregulation of glutamatergic ***,we identify a variety of cell types closely associated with PD risk *** together,our study provides valuable resources to systematically dissect the molecular mechanism of PD pathogenesis at the single-cell resolution,which facilitates the development of novel approaches for diagnosis and therapies against PD.

关键词： Parkinson’s disease α-syn-A53T Single-nucleus RNA-Seq Pathogenesis Neuroinflammtion

Sensitivity of seismic attenuation and dispersion to dynamic elastic interactions of connected fractures: Quasi-static finite element modeling study

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Petroleum Science 2023年第1期20卷 177-198页

作者： Yan-Xiao He Wen-Tao He Meng-Fan Zhang Jia-Liang Zhang Wei-Hua Liu Xiao-Yi Ma gen-Yang tang Shang-Xu Wang Guo-Fa Li Jun-Zhou Liu Xiang-Long Song State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development Beijing100083China Sinopec Key Laboratory of Seismic Elastic Wave Technology Beijing100083China State Key Laboratory of Petroleum Resources and Prospecting CNPC Key Lab of Geophysical ExplorationChina University of Petroleum(Beijing)Beijing102249China CNOOC(China)Co. Ltd.Hainan BranchHaikouHainan570311China PetroChina Dagang Oilfield Tianjin300280China Sinopec Geophysical Research Institute NanjingJiangsu211103China Sinopec Petroleum Exploration and Production Research Institute Beijing100083China Chinese Academy of Geological Sciences Beijing100037 China

Prediction of seismic attenuation and dispersion that are inherently sensitive to hydraulic and elastic properties of the medium of interest in the presence of mesoscopic fractures and pores,is of great interest in the characterization of fractured *** has been very difficult,however,considering that stress interactions between fractures and pores,related to their spatial distributions,tend to play a crucial role on affecting overall dynamic elastic properties that are largely *** thus choose to quantitatively investigate frequency-dependent P-wave characteristics in fractured porous rocks at the scale of a representative sample using a numerical scale-up procedure via performing finite element *** on 2-D numerical quasi-static experiments,effects of fracture and fluid properties on energy dissipation in response to wave-induced fluid flow at the mesoscopic scale are quantified via solving Biot's equations of *** show that numerical results are sensitive to some key characteristics of probed synthetic rocks containing unconnected and connected fractures,demonstrating that connectivity,aperture and inclination of fractures as well as fracture infills exhibit strong impacts on the two manifestations of WIFF mechanisms in the connected scenario,and on resulting total wave attenuation and phase ***,in turn,illustrates the importance of these two WIFF mechanisms in fractured rocks and thus,a deeper understanding of them may eventually allow for a better characterization of fracture systems using seismic ***,this presented work combines rock physics predictions with seismic numerical simulations in frequency domain to illustrate the sensitivity of seismic signatures on the monitoring of an idealized geologic CO_(2) sequestration in fractured *** simulation demonstrates that these two WIFF mechanisms can strongly modify seismic records and hence,indicating that incorporating the two energy dis

关键词： Attenuation and dispersion Rock physics Fractured media Frequency dependence Numerical study