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Magnetically controlled self-sealing pressure-preserved coring technology

Petroleum Science 2024年第5期21卷 3464-3481页

作者： Gui-Kang Liu He-Ping xie Cong Li zhen-xi you xiao-Jun Shi Jian-Jun Hu Ming-Zhong Gao State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065SichuanChina Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Institute of Deep Earth Sciences and Green EnergyCollege of Civil and Transportation EngineeringShenzhen UniversityShenzhen518060GuangdongChina School of Mechanical Engineering Sichuan UniversityChengdu610065SichuanChina

Pressure-preserved coring is an effective means to develop deep resources. However, due to the complexity of existing pressure-preserved technology, the average success rate of pressure-preserved coring is low. In response, a novel in situ magnetically controlled self-sealing pressure-preserved coring technology for deep reserves has been proposed and validated. This innovative technology distinguishes itself from conventional methods by employing noncontact forces to replace traditional pretensioning mechanisms, thereby enhancing the mechanical design of pressure-preserved coring equipment and significantly boosting the fault tolerance of the technology. Here, we report on the design,theoretical calculations, experimental validation, and industrial testing of this technology. Through theoretical and simulation calculations, the self-sealing composite magnetic field of the pressure controller was optimized. The initial pre-tensioning force of the optimal magnetic field was 13.05 N. The reliability of the magnetically controlled self-sealing pressure-preserved coring technology was verified using a self-developed self-sealing pressure performance testing platform, confirming the accuracy of the composite magnetic field calculation theory. Subsequently, a magnetically controlled self-triggering pressure-preserved coring device was designed. Field pressure-preserved coring was then conducted,preliminarily verifying the technology's effective self-sealing performance in industrial ***, the technology was analyzed and verified to be adaptable to complex reservoir environments with pressures up to 30 MPa, temperatures up to 80℃, and p H values ranging from 1 to 14. These research results provide technical support for multidirectional pressure-preserved coring, thus paving a new technical route for deep energy exploration through coring.

关键词： In situ pressure-preserved coring Magnetically controlled Self-sealing Magnetic design Deep earth exploration

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Contact performance analysis of pressure controller's sealing interface in deep in-situ pressure-preserved coring system

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Petroleum Science 2022年第3期19卷 1334-1346页

作者： Jia-Nan Li Jun Wang Yun-Qi Hu zhen-xi you Meng Xu Ying-Wei Wang Zu-Jie Zou Qi-Yue Kang School of Mechanical Engineering MOE Key Laboratory of Deep Underground Science and EngineeringCollege of Water Resource and HydropowerSichuan UniversityChengdu610065China Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Institute of Deep Earth Sciences and Green EnergyCollege of Civil and Transportation EngineeringShenzhen UniversityShenzhen518061China State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China State Key Laboratory of Coking Coal Exploitation and Comprehensive Utilization Pingdingshan Tianan Coal Mining Co.LTD.Pingdingshan467000China xi'an Research Institute China Coal Technology&Engineering Group CorpXi'an710077China

The sealing performance of contact interfaces plays the most important role in the design and operation of the in-situ pressure-preserved coring *** meet the demand of ultra-high pressure-retained coring for oil and gas exploration in deep reservoirs,a quantitative analysis of the contact mechanical behavior of the pressure controller was *** on the micro-contact theory of rough surfaces,a three-dimensional numerical model of the rough contact interface between the valve cover and the valve seat was constructed,and the micro-contact behavior of the metal contact surfaces was comprehensively *** results show that the actual contact area of the valve interface increases with the increase of surface roughness before the critical contact point,but decreases after *** with the real contact model with double rough surfaces,although the simplified hard-contact model with a single rough surface can reflect the micro-contact behavior of the rough surface to a certain extent,it cannot truly reveal the microchannel morphology between the sealing interfaces under ***,the realistic double-rough-surface model should be recommended to evaluate the sealing performance of coring tools,particularly for high pressure *** material properties of valves have a significant effect on the contact characteristics of rough surfaces,which suggested that the actual contact area decreases with the increase of the elastic modulus of the contact material under the same loading *** knowledge of this work could help to enhance the seal design of pressure controllers for in-situ pressure-preserved coring.

关键词： In-situ pressure-preserved coring Metal seal Rough surface Micro contact

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Atorvastatin Attenuates Myocardial Hypertrophy Induced by Chronic Intermittent Hypoxia In Vitro Partly through miR-31/PKCε Pathway

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Current Medical Science 2018年第3期38卷 405-412页

作者： Jie REN Wei LIU Guang-cai LI Meng JIN zhen-xi you Hui-guo LIU Yi HU Department of Respiratory and Critical Care Medicine Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China Department of Respiratory and Critical Care Medicine The Central Hospital of Wuhan Tongji Medical College Huazhong University of Science and Technology Wuhan 430010 China

Atorvastatin is proven to ameliorate cardiac hypertrophy induced by chronic intermittent hypoxia （CIH）. However, little is known about the mechanism by which atorvastatin modulates CIH-induced cardiac hypertrophy, and whether specific hypertrophyrelated microRNAs are involved in the modulation. MiR-31 plays key roles in the development of cardiac hypertrophy induced by ischemia/hypoxia. This study examined whether miR-31 was involved in the protective role of atorvastatin against CIH-induced myocardial hypertrophy. H9c2 cells were subjected to 8-h intermittent hypoxia per day in the presence or absence of atorvastatin for 5 days. The size of cardiomyocytes, and the expression of caspase 3 and miR-31 were determined by Western blotting and RT-PCR, respectively. MiR-31 mimic or Ro 31-8220, a specific inhibitor of protein kinase C epsilon （PKCε）, was used to determine the role of miR-31 in the anti-hypertrophic effect of atorvastatin on cardiomyocytes. PKCε in the cardiomyocytes with miR-31 upregulation or downregulation was detected using RT-PCR and Western blotting. The results showed that CIH induced obvious enlargement of cardiomyocytes, which was paralleled with increased atrial natriuretic peptide （ANP）, brain natriuretic peptide （BNP）, and slow/beta cardiac myosin heavy-chain （MYHT） mRNA levels. All these changes were reversed by the treatment with atorvastatin. Meanwhile, miR-31 was increased by CIH in vitro. Of note, the atorvastatin pretreatment significantly increased the mRNA and protein expression of PKCε and decreased that of miR-31. Moreover, overexpression of miR-31 abolished the anti-hypertrophic effect of atorvastatin on cardiomyocytes. Upregulation and downregulation of miR-31 respectively decreased and increased the mRNA and protein expression of PKCε. These results suggest that atorvastatin provides the cardioprotective effects against CIH probably via up-regulating PKCε and down-regulating miR-31.

关键词： atorvastatin chronic intermittent hypoxia myocardial remodeling miR-31 protein kinase C epsilon

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A promising approach for quantifying focal stroke modeling and assessing stroke progression:optical resolution photoacoustic microscopy photothrombosis

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Neural Regeneration Research 2025年第7期20卷 2029-2037页

作者： xiao Liang xingping Quan xiaorui Geng Yujing Huang Yonghua Zhao Lei xi zhen Yuan Ping Wang Bin Liu Faculty of Health Sciences University of MacaoMacao Special Administrative RegionChina Center for Cognitive and Brain Sciences University of MacaoMacao Special Administrative RegionChina Department of Biomedical Engineering Southern University of Science and TechnologyShenzhenGuangdong ProvinceChina State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoTaipaMacao Special Administrative RegionChina Department of Emergency Zhujiang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina

To investigate the mechanisms underlying the onset and progression of ischemic stroke,some methods have been proposed that can simultaneously monitor and create embolisms in the animal cerebral ***,these methods often require complex systems and the effect of age on cerebral embolism has not been adequately studied,although ischemic stroke is strongly *** this study,we propose an optical-resolution photoacoustic microscopy-based visualized photothrombosis methodology to create and monitor ischemic stroke in mice simultaneously using a 532 nm pulsed *** observed the molding process in mice of different ages and presented age-dependent vascular embolism ***,we integrated optical coherence tomography angiography to investigate age-associated trends in cerebrovascular variability following a *** imaging data and quantitative analyses underscore the differential cerebrovascular responses to stroke in mice of different ages,thereby highlighting the technique's potential for evaluating cerebrovascular health and unraveling age-related mechanisms involved in ischemic strokes.

关键词： age-dependent cerebral cortex ischemic stroke mouse model optical coherence tomography angiography photoacoustic microscopy photothrombosis vascular imaging

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基于SEM模型的城市公交服务市民满意度研究——以乌鲁木齐市为例

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哈尔滨商业大学学报（社会科学版） 2016年第6期 71-79页

作者：刘希珍贾友军王松新疆农业大学管理学院乌鲁木齐830052

公交服务是城市居民正常工作、出行的必要保障,为了解市民对当前公交服务的满意度情况,通过以调查问卷和访谈的形式对乌鲁木齐市的500人进行调查,并通过五级评分和SEM模型对乌鲁木齐市公交服务市民满意度进行实证分析。研究结果显示,59... 详细信息

公交服务是城市居民正常工作、出行的必要保障,为了解市民对当前公交服务的满意度情况,通过以调查问卷和访谈的形式对乌鲁木齐市的500人进行调查,并通过五级评分和SEM模型对乌鲁木齐市公交服务市民满意度进行实证分析。研究结果显示,59.1%的市民对当前公交服务表示不太满意,公交服务总体满意度总体平均得分仅为2.34分。其中,经济便捷和行车安全对公交服务市民满意度有直接正向影响,营运秩序和车貌车况则有间接正向影响。根据调查研究结果,提出加强对公交服务的财政投入、制定统一的公交服务收费标准、完善公交路线规划与站台设置等政策建议,为后续公交政策的制定提供实证参考。

关键词： SEM 公交服务市民满意度

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New perspective in statistical modeling of wall-bounded turbulence

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Acta Mechanica Sinica 2010年第6期26卷 847-861页

作者： zhen-Su She xi Chen you Wu Fazle Hussain State Key Laboratory for Turbulence and Complex Systems and Department of Mechanical and Aerospace Engineering College of EngineeringPeking University100871 BeijingChina Department of Mechanical Engineering University of Houston HoustonTX 77204-4792USA

Despite dedicated effort for many decades,statistical description of highly technologically important wall turbulence remains a great *** models are unfortunately incomplete,or empirical,or *** a review of the existing theories of wall turbulence,we present a new framework,called the structure ensemble dynamics （SED）,which aims at integrating the turbulence dynamics into a quantitative description of the mean *** SED theory naturally evolves from a statistical physics understanding of non-equilibrium open systems,such as fluid turbulence, for which mean quantities are intimately coupled with the fluctuation *** from the ensemble-averaged Navier-Stokes（EANS） equations,the theory postulates the existence of a finite number of statistical states yielding a multi-layer picture for wall ***,it uses order functions（ratios of terms in the mean momentum as well as energy equations） to characterize the states and transitions between *** of the SED analysis to an incompressible channel flow and a compressible turbulent boundary layer shows that the order functions successfully reveal the multi-layer structure for wall-bounded turbulence, which arises as a quantitative extension of the traditional view in terms of sub-layer,buffer layer,log layer and wake. Furthermore,an idea of using a set of hyperbolic functions for modeling transitions between layers is proposed for a quantitative model of order functions across the entire flow *** conclude that the SED provides a theoretical framework for expressing the yet-unknown effects of fluctuation structures on the mean quantities,and offers new methods to analyze experimental and simulation *** with asymptotic analysis,it also offers a way to evaluate convergence of *** SED approach successfully describes the dynamics at both momentum and energy levels, in contrast with all prevalent approaches describing the mean velocity profile

关键词： Wall turbulence Statistical modeling Structure ensemble dynamics Order function Multi-layer

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Effect of alginic acid decomposing bacterium on the growth of Laminaria japonica (Phaeophyceae)

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Journal of Environmental Sciences 2006年第3期18卷 543-551页

作者： WANG you TANG Xue-xi YANG zhen YU Zhi-ming College of Marine Life Science Ocean University of China Qingdao 266003 China The Key Laboratory of Marine Ecology and Environmental Sciences Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China

We collected the diseased blades of Larninaria japonica from Yantai Sea Farm from October to December 2002, and the alginic acid decomposing bacterium on the diseased blade was isolated and purified, and was identified as A lteromonas espejiana. This bacterium was applied as the causative pathogen to infect the blades of L. japonica under laboratory conditions. The aim of the present study was to identify the effects of the bacterium on the growth of L. japonica, and to find the possibly effective mechanism. Results showed that：（1）The blades of *** exhibited symptoms of lesion,bleaching and deteriortion when infected by the bacterium. and their growth and photosynthesis were dramatically suppressed. At the same time, the reactive oxygen species （ROS） generation enhanced obviously, and the relative membrane permeability increased significantly. The contents of malonaldehyde （MDA） and free fatty acid in the microsomol membrane greatly elevated, but the phospholipid content decreased. Result suggested an obvious peroxidation and deesterrification in the blades of L. japonica when infected by the bacterium. （2） The simultaneous assay on the antioxidant enzyme activities demonstrated that superoxide dismutase （SOD） and catalase （CAT） increased greatly when infected by the bacterium, but glutathione peroxidase （Gpx） and ascorbate peroxidase （APX） did not exhibit active responses to the bacterium throughout the experiment. （3） The histomorphological observations gave a distinctive evidence of the severity of the lesions as well as the relative abundance in the bacterial population on the blades after infection. The bacterium firstly invaded into the endodermis of L. japonica and gathered around there, and then resulted in the membrane damage, cells corruption and ultimately, the death of L. japonica.

关键词： Laminaria japonica alginic acid decomposing bacterial infection growth mechanism

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Ratiometric mode with dyads: a breakthrough in dynamic trapping and quantification for redox regulation in living cells

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Science China Chemistry 2015年第3期58卷 434-435页

作者： zhen xi College of Chemistry Nankai University

Redox-based post-translational modification of protein thiols has become an attractive strategy in cellular homeostasis and cell signaling. Due to the reductive end of the redox buffer network, the vicinal dithiol-containing proteins （VDPs） maintains an appropriate oxidation-reduction state of proteins through the reversible transformation from vicinal dithiols to disulfide, which is responsible for a variety of diseases, such as cancer, diabetes and neuro-degeneration.

关键词：氧化还原状态活细胞调控诱捕比例蛋白质二硫醇细胞信号

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PEN/BADCy Interlayer Dielectric Films with Tunable Microstructures via an Assist of Temperature for Enhanced Frequency Stability

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Chinese Journal of Polymer Science 2020年第11期38卷 1258-1266,I0009页

作者： xi-Ting Lei Li-Fen Tong Ming-zhen Xu Yong you xiao-Bo Liu School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 610054China

Low dielectric in terlayer films have become an important element to ensure the development of the microelectr onics industry.A kind of flexible interlayer dielectrics,polyarylene ether nitrile/bisphenol A cyanate ester(PEN/BADCy)film,with good thermal stability and low frequency dependence,has been developed by solution casting ***,materials were designed to incorporate bisphenol A cyanate ester as a part of blend,contributing to the frequency stability and structural *** morphological study combined with electron microscopy revealed the uniform and flexible microstructure information with controllable morphology through self-polymerization of cyanate esters with different prepolymerization time and curing *** dielectric films could present high thermal stability with Tg>180℃.Significant improvement in the dielectric properties was achieved for the dielectric constant and loss was much stabler than neat PEN over the frequency range from 100 Hz to 5 *** the prepolymerization time was 3h and final curing temperature reached 230℃,the dielectric constant and dielectric loss of the films were 3.36 and 0.013 at 100 kHz,*** dimensional stability(CTE=53.67×10^-6 K^-1)was confirmed and con sidered beneficial to use as an in terlayer dielectrics.

关键词： Polyarylene ether nitrile Bisphenol A cyanate ester Interlayer dielectrics Tunable microstructures

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A Study on the Technique of Observing Interplanetary Scintillation with Simultaneous Dual-Frequency Measurements

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Chinese Journal of Astronomy and Astrophysics 2007年第5期7卷 712-720页

作者： xi-zhen Zhang National Astronomical Observatories Chinese Academy of Sciences Beijing 100012

Ground-based observation of Interplanetary Scintillation （IPS） is an important approach of monitoring solar wind speed. We describe both the principle and method of observing the solar wind speed by using the normalized cross-spectrum of simultaneous dualfrequency IPS measurement. The effects of the solar wind properties and the angular size of the scintillation source on the measurement of solar wind speed are investigated by numerical analysis. We carry out a comparison of this method with the traditional single station-single frequency method. We outline a new IPS observation system using this method now under construction at the National Astronomical Observatories, CAS （NAOC）.

关键词： interplanetary scintillation -- method -- instrument -- telescope

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