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TBAB hydrate formation and growth in a microdevice under static and dynamic conditions

Petroleum Science 2024年第2期21卷 1396-1404页

作者： Xingxun Li Ming Liu Qingping Li Weixin Pang Guangjin Chen Changyu Sun state key laboratory of Heavy Oil Processing China University of Petroleum BeijingBeijing102249China state key laboratory of natural gas hydrate CNOOC Research Institute Co.Ltd.Beijing100027China

The natural gas hydrate has become one of the most promising future green energy sources on the earth.The natural gas hydrates mostly exist in the sediments with porous structure, so a solid understanding of the hydrate formation and growth processes in the porous medium is of significance for the exploitation of natural gas hydrate. The micro-packed bed device is one of the efficient microfluidic devices in the engineering field, but it has been rarely used for the hydrate-based research. In this study, a transparent micro-packed bed device filled with glass beads was developed to mimic the porous condition of sediments, and used to in-situ visualize the hydrate formation and growth habits in the pore spaces under both static and dynamic conditions. For the static experiment, two types of hydrate growth patterns in porous medium were observed and identified in the micro-packed bed device, which were the graincoating growth and pore-filling growth. For the dynamic condition, the hydrate formation, growth,distribution habits and hydrate blockage phenomena in the pore spaces were in-situ visually captured.The impacts of flowrate and subcooling on the pressure variation of the micro-packed bed and the duration of the hydrate growth under dynamic flow condition in pores were in-situ monitored and analyzed. The higher flowrate could result in the faster hydrate growth and more severe blockage in pores, but the effect of subcooling condition might be less significant at the high flowrate.

关键词： hydrate formation hydrate growth Microdevice In-situ measurement

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Influence of pressure disturbance wave on dynamic response characteristics of liquid film seal for multiphase pump

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Petroleum Science 2024年第3期21卷 2048-2065页

作者： Qing-Ping Li Jin-Ya Zhang Jia-Xiang Zhang Yong-Xue Zhang CNOOC Research Institute Company Limited state key laboratory of natural gas hydrate College of Mechanical and Transportation Engineering China University of Petroleum

Slug flow or high GVF(gas Volume Fraction) conditions can cause pressure disturbance waves and alternating loads at the boundary of mechanical seals for multiphase pumps, endangering the safety of multiphase pump units. The mechanical seal model is simplified by using periodic boundary conditions and numerical calculations are carried out based on the Zwart-Gerber-Belamri cavitation model. UDF(User Define Function) programs such as structural dynamics equations, alternating load equations, and pressure disturbance equations are embedded in numerical calculations, and the dynamic response characteristics of mechanical seal are studied using layered dynamic mesh technology. The results show that when the pressure disturbance occurs at the inlet, as the amplitude and period of the disturbance increase, the film thickness gradually decreases. And the fundamental reason for the hysteresis of the film thickness change is that the pressure in the high-pressure area cannot be restored in a timely manner. The maximum value of leakage and the minimum value of axial velocity are independent of the disturbance period and determined by the disturbance amplitude. The mutual interference between enhanced waves does not have a significant impact on the film thickness, while the front wave in the attenuated wave has a promoting effect on the subsequent film thickness changes, and the fluctuation of the liquid film cavitation rate and axial velocity under the attenuated wave condition deviates from the initial values. Compared with pressure disturbance conditions, alternating load conditions have a more significant impact on film thickness and leakage. During actual operation, it is necessary to avoid alternating load conditions in multiphase pump mechanical seals.

关键词： Multiphase pump Liquid film seal Pressure disturbance wave Dynamic response characteristics

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Discovery of proqodine A derivatives with antitumor activity targeting NAD(P)H:quinone oxidoreductase 1 and nicotinamide phosphoribosyltransferase

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Chinese Journal of natural Medicines 2024年第1期22卷 75-88页

作者： SONG Jiangzhou ZOU Guiqing ZHAO Zhou ZHU Ya XUE Jiayu AO Lanjia SUN Huiyong HAO Haiping ZHANG Bo XU Xiaowei state key laboratory of natural Medicines Key Lab of Drug Metabolism and PharmacokineticsChina Pharmaceutical UniversityNanjing 210009China state key laboratory of natural Medicines China Pharmaceutical UniversityNanjing 210009China

NAD(P)H:quinone oxidoreductase 1(NQO1)is a flavin protease highly expressed in various cancer cells.NQO1 catalyzes a futile redox cycle in substrates,leading to substantial reactive oxygen species(ROS)production.This ROS generation results in extensive DNA damage and elevated poly(ADP-ribose)polymerase 1(PARP1)-mediated consumption of nicotinamide adenine dinucleotide(NAD^(+)),ultimately causing cell death.Nicotinamide phosphoribosyltransferase(NAMPT),the rate-limiting enzyme in the NAD^(+)salvage synthesis pathway,emerges as a critical target in cancer therapy.The concurrent inhibition of NQO1 and NAMPT triggers hyperactivation of PARP1 and intensive NAD+depletion.In this study,we designed,synthesized,and assessed a novel series of proqodine A derivatives targeting both NQO1 and NAMPT.Among these,compound T8 demonstrated potent antitumor properties.Specifically,T8 selectively inhibited the proliferation of MCF-7 cells and induced apoptosis through mechanisms dependent on both NQO1 and NAMPT.This discovery offers a promising new molecular entity for advancing anticancer research.

关键词： NQO1 ROS NAMPT NAD^(+) T8

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Progress in approved drugs from natural product resources

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Chinese Journal of natural Medicines 2024年第3期22卷 195-211页

作者： LUO Zhongwen YIN Fucheng WANG Xiaobing KONG Lingyi state key laboratory of natural Medicines and Jiangsu key laboratory of Bioactive natural Product Research School of Traditional Chinese PharmacyChina Pharmaceutical UniversityNanjing 211198China

natural products (NPs) have consistently played a pivotal role in pharmaceutical research, exerting profound impactson the treatment of human diseases. A significant proportion of approved molecular entity drugs are either directly derived from NPs orindirectly through modifications of NPs. This review presents an overview of NP drugs recently approved in China, the United states,and other countries, spanning various disease categories, including cancers, cardiovascular and cerebrovascular diseases, centralnervous system disorders, and infectious diseases. The article provides a succinct introduction to the origin, activity, development process, approval details, and mechanism of action of these NP drugs.

关键词： New drugs natural products Structural modification

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Evaluation of the Shallow gas hydrate Production Based on the Radial Drilling-Heat Injection-Back Fill Method

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Journal of Ocean University of China 2024年第1期23卷 119-128页

作者： CHEN Qiang WAN Yizhao WU Nengyou SUN Jianye WANG Jian LIU Changling LI Yanlong LI Chengfeng HU Gaowei key laboratory of gas hydrate Ministry of Natural ResourcesQingdao 266071China laboratory for Marine Mineral Resources Laoshan LaboratoryQingdao 266071China CNPC Offshore Engineering Company Limited Beijing 100028China Technology Innovation Center for Marine Methane Monitoring Ministry of Natural ResourcesQingdao 266071China

It has been evidenced that shallow gas hydrate resources are abundant in deep oceans worldwide.Their geological back-ground,occurrence,and other characteristics differ significantly from deep-seated hydrates.Because of the high risk of well construction and low production efficiency,they are difficult to be recovered by using conventional oil production methods.As a result,this paper proposes an alternative design based on a combination of radial drilling,heat injection,and backfilling methods.Multi-branch holes are used to penetrate shallow gas hydrate reservoirs to expand the depressurization area,and heat injection is utilized as a supplement to improve gas production.Geotechnical information collected from an investigation site close to the offshore production well in the South China Sea is used to assess the essential components of this plan,including well construction stability and gas production behavior.It demonstrates that the hydraulic fracturing of the 60mbsf overburden layer can be prevented by regulating the drilling fluid densities.However,the traditional well structure is unstable,and the suction anchor is advised for better mechanical performance.The gas produc-tion rate can be significantly increased by combining hot water injection and depressurization methods.Additionally,the suitable produc-tion equipment already in use is discussed.

关键词： shallow gas hydrate trail production radial drilling-heat injection-back fill method experimental and numerical simulation

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Characteristics of Paleontological Communities in Surface Sediments of the Southern South China Sea and Their Paleoclimatic and Paleoenvironmental Significance

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Journal of Earth Science 2024年第1期35卷 144-154页

作者： Jing Zhao Li Zhang Xiaoyan Wang Jinglian Ge Min Xu Wei Chen Mao Luo Qianyong Liang Qiuhua Yu Shuaibing Luo Wenkun Qie key laboratory of Marine Mineral Resoures Ministry of Natural ResourcesGuangzhou Marine Geological SurveyChina Geological SurveyGuangzhou 511458China National Engineering Research Center for gas hydrate Exploration and Development Guangzhou 511458China state key laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China

Understanding the spatial and temporal distribution of different paleontological communities in the southern South China Sea(SCS)is fundamental to explore its paleoclimatic and paleoenvironmental changes.In this study,foraminifera,pollen and diatoms from 100 surface sediment samples covering 40000 km^(2) of sea floor in the southern SCS were comprehensively investigated in terms of their assemblage and distribution.The results showed the existence of abundant foraminifera and pollen in most of the samples,although diatom communities were relatively scarce.Foraminifera were dominated by G.sacculifer,G.menardii,G.ruber,while diatoms were characterized by T.simonsenii,T.nitzschioides and T.longissima,indicating a typical tropical marine environment.The pollen assemblages showed a better reflection of montane rainforest,tropical rainforest and mangrove.The spatial differences among foraminifera assemblages may indicate the effect of water depth and a warmer environment in the southeast part of the study area,while the spatial patterns of diatom and pollen assemblages imply the influence of coastal current.Our study also noted that the compositions of paleontological communities in the SCS can vary significantly in a short distance,and synthesized studies on multiple biological groups are needed to reconstruct the Quaternary climate and the oceanographic environment.

关键词： southern South China Sea sediments foraminifera diatom pollen

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A continuous and long-term in-situ stress measuring method based on fiber optic. Part I: Theory of inverse differential strain analysis

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Petroleum Science 2024年第2期21卷 1171-1189页

作者： Kun-Peng Zhang Mian Chen Chang-Jun Zhao Su Wang Yong-Dong Fan state key laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China MOE key laboratory of Petroleum Engineering in China University of Petroleum Beijing102249China Beijing International Center for gas hydrate School of Earth and Space SciencesPeking UniversityBeijing100871China

A method for in-situ stress measurement via fiber optics was proposed. The method utilizes the relationship between rock mass elastic parameters and in-situ stress. The approach offers the advantage of long-term stress measurements with high spatial resolution and frequency, significantly enhancing the ability to measure in-situ stress. The sensing casing, spirally wrapped with fiber optic, is cemented into the formation to establish a formation sensing nerve. Injecting fluid into the casing generates strain disturbance, establishing the relationship between rock mass properties and treatment pressure.Moreover, an optimization algorithm is established to invert the elastic parameters of formation via fiber optic strains. In the first part of this paper series, we established the theoretical basis for the inverse differential strain analysis method for in-situ stress measurement, which was subsequently verified using an analytical model. This paper is the fundamental basis for the inverse differential strain analysis method.

关键词： In-situ stress Fiber optic Orthotropic elastic Differential evolution ABAQUS

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Deformation Characteristics of hydrate-Bearing Sediments

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Journal of Ocean University of China 2024年第1期23卷 149-156页

作者： DONG Lin LI Yanlong ZHANG Yajuan HU Gaowei LIAO Hualin CHEN Qiang WU Nengyou key laboratory of gas hydrate Ministry of Natural ResourcesQingdao Institute of Marine GeologyQingdao 266237China laboratory for Marine Mineral Resources Laoshan LaboratoryQingdao 266237China College of Oceanography Hohai UniversityNanjing 210098China College of Petroleum Engineering China University of Petroleum(East China)Qingdao 266555China

The safe and efficient development of natural gas hydrate requires a deep understanding of the deformation behaviors of reservoirs.In this study,a series of triaxial shearing tests are carried out to investigate the deformation properties of hydrate-bearing sediments.Variations of volumetric and lateral strains versus hydrate saturation are analyzed comprehensively.Results indicate that the sediments with high hydrate saturation show dilative behaviors,which lead to strain-softening characteristics during shearing.The volumetric strain curves have a tendency to transform gradually from dilatation to compression with the increase in effective confining pressure.An easy prediction model is proposed to describe the relationship between volumetric and axial strains.The model coefficientβis the key dominating factor for the shape of volumetric strain curves and can be determined by the hydrate saturation and stress state.Moreover,a modified model is established for the calculation of lateral strain.The corresponding determination method is provided for the easy estimation of model coefficients for medium sand sediments containing hydrate.This study provides a theoretical and experimental reference for deformation estimation in natural gas hydrate development.

关键词： gas hydrate deformation characteristics volumetric strain lateral strain prediction model

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Exosomes derived from pulmonary metastatic sites enhance osteosarcoma lung metastasis by transferring the miR-194/215 cluster targeting MARCKS

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Acta Pharmaceutica Sinica B 2024年第5期14卷 2039-2056页

作者： Pei Yu Yubao Han Lulu Meng Yanyuan Tian Zhiwei Jin Jun Luo Chao Han Wenjun Xu Lingyi Kong Chao Zhang state key laboratory of natural Medicines Jiangsu Key Laboratory of Bioactive Natural Product ResearchSchool of Traditional Chinese PharmacyChina Pharmaceutical UniversityNanjing 211198China

Osteosarcoma,a prevalent primary malignant bone tumor,often presents with lung metastases,severely impacting patient survival rates.Extracellular vesicles,particularly exosomes,play a pivotal role in the formation and progression of osteosarcoma-related pulmonary lesions.However,the communication between primary osteosarcoma and exosome-mediated pulmonary lesions remains obscure,with the potential impact of pulmonary metastatic foci on osteosarcoma progression largely unknown.This study unveils an innovative mechanism by which exosomes originating from osteosarcoma pulmonary metastatic sites transport the miR-194/215 cluster to the primary tumor site.This transportation enhances lung metastatic capability by downregulating myristoylated alanine-rich C-kinase substrate(MARCKS)expression.Addressing this phenomenon,in this study we employ cationic bovine serum albumin(CBSA)to form nanoparticles(CBSA-anta-194/215)via electrostatic interaction with antagomir-miR-194/215.These nanoparticles are loaded into nucleic acid-depleted exosomal membrane vesicles(anta-194/215@Exo)targeting osteosarcoma lung metastatic sites.Intervention with bioengineered exosome mimetics(anta-194/215@Exo)not only impedes osteosarcoma progression but also significantly prolongs the lifespan of tumor-bearing mice.These findings suggest that pulmonary metastatic foci-derived exosomes initiate primary osteosarcoma lung metastasis by transferring the miR-194/215 cluster targeting MARCKS,making the miR-194/215 cluster a promising therapeutic target for inhibiting the progression of patients with osteosarcoma lung metastases.

关键词： Lung–bone transmission miR-194/215 cluster Exosome Lung metastasis Epithelial–mesenchymal transition Vasculogenic mimicry Bioengineered exosome mimetics Osteosarcoma

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Identifying and localizing of seismogenic electromagnetic anomalies from data observed by permanent MT stations

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Science China Earth Sciences 2024年第5期67卷 1698-1713页

作者： Bing HAN Wenbao HU Guoze ZHAO Ji TANG state key laboratory of Earthquake Dynamics Institute of GeologyBeijing 100029China key laboratory of Exploration Technologies for Oil and gas Resources of Ministry of Education Yangtze UniversityWuhan 430100China

In this research, an arbitrarily oriented electric dipole at subsurface is used to simulate Seismogenic Electromagnetic(SEM) radiation emanating from a seismic zone during its gestation phase. Analytical synthesis of responses at the Lijiang magnetotelluric(MT) station has revealed that SEM radiation could induce identifiable anomalies in the electromagnetic(EM)spectrum, apparent resistivity and phase within specific frequency bands. Background variations were extracted from long-term observation data of Dali and Lijiang MT stations, enabling the identification of SEM anomalies related to the Yunlong and Yangbi earthquakes. Multiple parameters of dipole sources at subsurface were obtained by applying the Differential Ant Colony Optimization(DACO) algorithm to anomalous data of two stations with multi-frequencies and various response functions. The spatial distribution of these predicted dipoles is predominantly clustered in or around the seismogenic area, with their azimuthal orientation aligning towards the seismogenic fault in general. This study has demonstrated the potential of using subsurface electric dipole simulations for SEM radiation analysis, offering a feasible approach for the prediction and understanding of seismogenic zones.

关键词： MT responses Identifying SEM anomaly Vector electric dipole responses Localizing SEM sources by inversion

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