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Comparative impact behaviours of ultra high performance concrete columns reinforced with polypropylene vs steel fibres
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作者 Thong M.Pham Harrison Hyde +4 位作者 Maw K.Kaung Yan Zhuge Duong T.Tran Des Vlietstra Tung M.Tran 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第10期138-153,共16页
Polypropylene(PP) fibres have primarily used to control shrinkage cracks or mitigate explosive spalling in concrete structures exposed to fire or subjected to impact/blast loads, with limited investigations on capacit... Polypropylene(PP) fibres have primarily used to control shrinkage cracks or mitigate explosive spalling in concrete structures exposed to fire or subjected to impact/blast loads, with limited investigations on capacity improvement. This study unveils the possibility of using PP micro-fibres to improve the impact behaviour of fibre-reinforced ultra-high-performance concrete(FRUHPC) columns. Results show that the addition of fibres significantly improves the impact behaviour of FRUHPC columns by shifting the failure mechanism from brittle shear to favourable flexural failure. The addition of steel or PP fibres affected the impact responses differently. Steel fibres considerably increased the peak impact force(up to 18%) while PP micro-fibres slightly increased the peak(3%-4%). FRUHPC significantly reduced the maximum midheight displacement by up to 30%(under 20°impact) and substantially improved the displacement recovery by up to 100%(under 20° impact). FRUHPC with steel fibres significantly improved the energy absorption while those with PP micro-fibres reduced the energy absorption, which is different from the effect of PP-macro fibre reported in the literature. The optimal fibre content for micro-PP fibres is 1% due to its minimal fibre usage and low peak and residual displacement. This study highlights the potential of FRUHPC as a promising material for impact-resistant structures by creating a more favourable flexural failure mechanism, enhancing ductility and toughness under impact loading, and advancing the understanding of the role of fibres in structural performance. 展开更多
关键词 ultra high-performance concrete Steel fibre Polypropylene micro-fibre Fibre volume fraction Impact loading Pendulum tests COLUMNS
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CO_(2) mineralization by typical industrial solid wastes for preparing ultrafine CaCO_(3): A review
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作者 Run Xu Fuxia Zhu +8 位作者 Liang Zou Shuqing Wang Yanfang Liu Jili Hou Chenghao Li Kuntong Song Lingzhao Kong Longpeng Cui Zhiqiang Wang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第11期1679-1697,共19页
Mineral carbonation is a promising CO_(2) sequestration strategy that can utilize industrial wastes to convert CO_(2) into high-value CaCO_(3).This review summarizes the advancements in CO_(2) mineralization using typ... Mineral carbonation is a promising CO_(2) sequestration strategy that can utilize industrial wastes to convert CO_(2) into high-value CaCO_(3).This review summarizes the advancements in CO_(2) mineralization using typical industrial wastes to prepare ultrafine CaCO_(3).This work surveys the mechanisms of CO_(2) mineralization using these wastes and its capacities to synthesize CaCO_(3),evaluates the effects of carbonation pathways and operating parameters on the preparation of CaCO_(3),analyzes the current industrial application status and economics of this technology.Due to the large amount of impurities in solid wastes,the purity of CaCO_(3) prepared by indirect methods is greater than that prepared by direct methods.Crystalline CaCO_(3) includes three polymorphs.The polymorph of CaCO_(3) synthesized by carbonation process is determined the combined effects of various factors.These parameters essentially impact the nucleation and growth of CaCO_(3) by altering the CO_(2) supersaturation in the reaction system and the surface energy of CaCO_(3) grains.Increasing the initial pH of the solution and the CO_(2)flow rate favors the formation of vaterite,but calcite is formed under excessively high pH.Vaterite formation is favored at lower temperatures and residence time.With increased temperature and prolonged residence time,it passes through aragonite metastable phase and eventually transforms into calcite.Moreover,polymorph modifiers can decrease the surface energy of CaCO_(3) grains,facilitating the synthesis of vaterite.However,the large-scale application of this technology still faces many problems,including high costs,high energy consumption,low calcium leaching rate,low carbonation efficiency,and low product yield.Therefore,it is necessary to investigate ways to accelerate carbonation,optimize operating parameters,develop cost-effective agents,and understand the kinetics of CaCO_(3) nucleation and crystallization to obtain products with specific crystal forms.Furthermore,more studies on life cycle assessment(LCA)should be conducted to fully confirm the feasibility of the developed technologies. 展开更多
关键词 Industrial solid wastes Resource utilization Mineral carbonation ultrafine CaCO_(3) Carbon emission reduction
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Spatiotemporal mapping of(ultra‐)mafic magmatic mine areas:Implications of economic and political realities in China
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作者 Heling Li Liang Tang +3 位作者 Tim T.Werner Zhengmeng Hou Fan Meng Jingjing Li 《Deep Underground Science and Engineering》 2024年第1期91-102,共12页
The spatiotemporal extension/expansion of mine areas is affected by multiple factors.So far,very little has been done to examine the interaction between mine areas and political or economic realities.The(ultra‐)mafic... The spatiotemporal extension/expansion of mine areas is affected by multiple factors.So far,very little has been done to examine the interaction between mine areas and political or economic realities.The(ultra‐)mafic magmatic mines in China played a specific role in supporting national development and providing an ideal research subject for monitoring their interrelationship.In this study,remote sensing and mining‐related GIS data were used to identify and analyze 1233(ultra‐)mafic magmatic mine area polygons in China,which covered approximately 322.96 km2 of land and included a V–Ti–Fe mine,a copper–nickel mine,a chromite mine,an asbestos mine,and a diamond mine.It was found that(1)the areal expansion of mines is significantly related to the mine types,perimeter,topography,and population density.(2)The mine area variation also reflects market and policy realities.The temporal expansion of the mine area from 2010 to 2020 followed an S‐shaped pattern(with the turning point occurring in 2014),closely related to iron overcapacity and tightened mining policies.(3)The complexity(D)of the mine area may reflect mine design and excavation practices.To be specific,lower D indicates early‐stage or artisanal/small‐scale mining,whereas higher D represents large‐scale mining.This study demonstrates that the detailed mapping of mine land can serve as an indicator to implement miningrelated market and policy changes.The(ultra‐)mafic mines area data set can be accessed at https://zenodo.org/record/7636616#.Y-p0uXaZOa0. 展开更多
关键词 complexity mine area mining and socioeconomic interaction spatiotemporal distribution (ultra‐)mafic magmatic mine
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Xpert MTB/RIF Ultra在儿童结核诊断中的应用价值
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作者 王小杰 周正 《医药前沿》 2024年第18期23-26,共4页
目的:探讨Xpert MTB/RIF Ultra在儿童结核诊断中的应用价值。方法:选取2010年1月—2022年12月山东省公共卫生临床中心收治的150例患儿作为研究对象。根据临床综合诊断确诊结果将结核病感染患儿纳入试验组(n=100),将非结核病感染患儿纳... 目的:探讨Xpert MTB/RIF Ultra在儿童结核诊断中的应用价值。方法:选取2010年1月—2022年12月山东省公共卫生临床中心收治的150例患儿作为研究对象。根据临床综合诊断确诊结果将结核病感染患儿纳入试验组(n=100),将非结核病感染患儿纳入对照组(n=50)。计算不同标本类型的敏感度、特异度、阴性预测值、阳性预测值和准确度,评价Xpert MTB/RIF Ultra检出利福平(RIF)耐药性的效能。结果:Xpert MTB/RIF Ultra的检测所有标本总敏感度为77.00%,特异度为96.00%;合并肺内标本敏感度为92.85%,特异度为96.29%,其中肺内标本中肺泡灌洗液敏感度最高为100.00%;合并肺外标本敏感度为77.55%,特异度为95.65%,其中肺外标本中淋巴结敏感度最高为100.00%。结论:不同标本类型中Xpert MTB/RIF Ultra对儿童结核的检出率差异较大,在诊断肺内结核标本时,检测肺泡灌洗液标本价值最高,在诊断肺外结核标本时,检测淋巴结标本价值最高。 展开更多
关键词 儿童 结核 Xpert MTB/RIF ultra 标本
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Xpert MTB/RIF Ultra对结核性脑膜炎的早期诊断价值
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作者 杨元利 张永峰 杨翰 《陕西医学杂志》 CAS 2024年第4期544-547,568,共5页
目的:评价Xpert MTB/RIF Ultra(Ultra)对结核性脑膜炎(TBM)的早期诊断价值。方法:对79例患者的临床资料进行分析,用Ultra、Xpert MTB/RIF(Xpert)、宏基因测序(mNGS)和分枝杆菌培养(MGIT)检测脑脊液(CSF)中的结核分枝杆菌。在临床诊断的... 目的:评价Xpert MTB/RIF Ultra(Ultra)对结核性脑膜炎(TBM)的早期诊断价值。方法:对79例患者的临床资料进行分析,用Ultra、Xpert MTB/RIF(Xpert)、宏基因测序(mNGS)和分枝杆菌培养(MGIT)检测脑脊液(CSF)中的结核分枝杆菌。在临床诊断的基础上,分析各方法的检测性能和利福平药物敏感性。结果:Ultra的敏感度(56.4%)、曲线下面积(AUC值)和Kappa值(0.521)均高于MGIT(20%、0.600、0.236)、Xpert(40%、0.700、0.236)和mNGS(32.7%、0.664、0.352)。在31例Ultra阳性病例中,24例对利福平敏感,7例耐药性不确定。结论:与其他方法相比,Ultra检测脑脊液中结核分枝杆菌具有较高的敏感性。因此,Ultra可用于TBM的早期诊断。 展开更多
关键词 脑脊液 诊断 结核性脑膜炎 Xpert MTB/RIF Xpert MTB/RIF ultra 宏基因测序
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Anisotropy of Trabecular Bone from Ultra-Distal Radius Digital X-Ray Imaging: Effects on Bone Mineral Density and Age
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作者 Jian-Feng Chen 《Open Journal of Radiology》 2024年第1期14-23,共10页
Background: When applied to trabecular bone X-ray images, the anisotropic properties of trabeculae located at ultra-distal radius were investigated by using the trabecular bone scores (TBS) calculated along directions... Background: When applied to trabecular bone X-ray images, the anisotropic properties of trabeculae located at ultra-distal radius were investigated by using the trabecular bone scores (TBS) calculated along directions parallel and perpendicular to the forearm. Methodology: Data from more than two hundred subjects were studied retrospectively. A DXA (GE Lunar Prodigy) scan of the forearm was performed on each subject to measure the bone mineral density (BMD) value at the location of ultra-distal radius, and an X-ray digital image of the same forearm was taken on the same day. The values of trabecular bone score along the direction perpendicular to the forearm, TBS<sub>x</sub>, and along the direction parallel to the forearm, TBS<sub>y</sub>, were calculated respectively. The statistics of TBS<sub>x</sub> and TBS<sub>y</sub> were calculated, and the anisotropy of the trabecular bone, which was defined as the ratio of TBS<sub>y</sub> to TBS<sub>x</sub> and changed with subjects’ BMD and age, was reported and analyzed. Results: The results show that the correlation coefficient between TBS<sub>x</sub> and TBS<sub>y</sub> was 0.72 (p BMD and age was reported. The results showed that decreased trabecular bone anisotropy was associated with deceased BMD and increased age in the subject group. Conclusions: This study shows that decreased trabecular bone anisotropy was associated with decreased BMD and increased age. 展开更多
关键词 ANISOTROPY Trabecular Bone Score Bone Mineral Density ultra-Distal Radius Digital X-Ray Image
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Characteristics of helical flow in slim holes and calculation of hydraulics for ultra-deep wells 被引量:1
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作者 Fu Jianhong Yang Yun +1 位作者 Chen Ping Zhao Jinhai 《Petroleum Science》 SCIE CAS CSCD 2010年第2期226-231,共6页
Due to the slim hole at the lower part of the ultra-deep and deep wells, the eccentricity and rotation of drill string and drilling fluid properties have great effects on the annular pressure drop. This leads to the f... Due to the slim hole at the lower part of the ultra-deep and deep wells, the eccentricity and rotation of drill string and drilling fluid properties have great effects on the annular pressure drop. This leads to the fact that conventional computational models for predicting circulating pressure drop are inapplicable to hydraulics design of deep wells. With the adoption of helical flow theory and H-B rheological model, a computational model of velocity and pressure drop of non-Newtonian fluid flow in the eccentric annulus was established for the cases where the drill string rotates. The effects of eccentricity, rotation of the drill string and the dimensions of annulus on pressure drop in the annulus were analyzed. Drilling hydraulics was given for an ultra-deep well. The results show that the annular pressure drop decreases with an increase in eccentricity and rotary speed, and increases with a decrease in annular flow area. There is a great difference between static mud density and equivalent circulating density during deep well drilling. 展开更多
关键词 ultra-deep well slim hole annular velocity annular pressure drop hydraulics
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Xpert MTB/RIF Ultra在快速检测结核分枝杆菌和利福平耐药中的应用 被引量:5
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作者 王垚 林珍丽 +1 位作者 陈新朝 黄明翔 《分子诊断与治疗杂志》 2023年第5期871-875,共5页
目的探讨Xpert MTB/RIF Ultra在快速检测结核分枝杆菌和利福平耐药中的应用价值。方法收集2019年12月至2020年5月就诊于福州肺科医院的447例疑似肺结核患者的痰标本,分别进行MGIT960液体培养及药敏、Xpert MTB/RIF(Xpert)和Xpert Ultra... 目的探讨Xpert MTB/RIF Ultra在快速检测结核分枝杆菌和利福平耐药中的应用价值。方法收集2019年12月至2020年5月就诊于福州肺科医院的447例疑似肺结核患者的痰标本,分别进行MGIT960液体培养及药敏、Xpert MTB/RIF(Xpert)和Xpert Ultra检测,将检出MTB的菌株和痰液进行rpoB基因Sanger测序。以临床诊断结果为参照,比较MGIT960液体培养、Xpert、Xpert Ultra检测MTB的敏感度和特异度;分别以液体药敏和测序结果为金标准,评价Xpert Ultra检测MTB利福平耐药性的效能。结果以临床确诊为参照,Xpert Ultra敏感度高于液体培养和Xpert,差异有统计学意义(χ^(2)=28.97、164.86,P均<0.05),特异度与液体培养和Xpert比较差异无统计学意义(P均>0.05)。分别以利福平液体药敏表型结果和rpoB基因测序结果为金标准,Xpert Ultra的敏感度为88.89%和93.75%。同时经测序分析,35例利福平耐药样本中,rpoB的531位点突变最为常见,占48.57%。结论Xpert Ultra能快速检测痰液中的MTB及其利福平耐药性,对肺结核早期诊疗有良好的临床应用价值,适合在各级实验室推广。 展开更多
关键词 Xpert MTB/RIF ultra 结核分枝杆菌 利福平 耐药
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Mechanism and prevention method of drill string uplift during shut-in after overflow in an ultra-deep well
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作者 YIN Hu SI Menghan +2 位作者 LI Qian JANG Hongwei DAI Liming 《Petroleum Exploration and Development》 2018年第6期1139-1145,共7页
Drill string will sustain large uplift force during the shut-in period after gas overflow in an ultra-deep well, and in serious case, it will run out of the wellhead. A calculation model of uplift force was establishe... Drill string will sustain large uplift force during the shut-in period after gas overflow in an ultra-deep well, and in serious case, it will run out of the wellhead. A calculation model of uplift force was established to analyze dynamic change characteristics of the uplift force of drill string during the shut-in period, and then a management procedure for the uplift risk during the shut-in period after gas overflow in the ultra-deep well was formed. Cross section method and pressure area method were used to analyze the force on drill string after shut-in of well, it was found that the source of uplift force was the "fictitious force" caused by the hydrostatic pressure in the well. When the fictitious force is in the opposite direction to the gravity, it is the uplift force. By adopting the theory of annular multiphase flow, considering the effects of wellbore afterflow and gas slippage, the dynamic change of the pressure and fluid in the wellbore and the uplift force of drill string during the shut-in period were analyzed. The magnitude and direction of uplift force are related to the length of drill string in the wellbore and shut-in time, and there is the risk of uplift of drill string when the length of drill string in the wellbore is smaller than the critical drill string length or the shut in time exceeds the critical shut in time. A set of treatment method and process to prevent the uplift of drill string is advanced during the shut-in period after overflow in the ultra-deep well, which makes the risk management of the drill string uplift in the ultra-deep well more rigorous and scientific. 展开更多
关键词 ultra-deep well drilling OVERFLOW shut-in DRILL STRING UPLIFT force axial load
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Reliability Analysis of Super 13Cr Tubing in Ultra-Deep Gas Well
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作者 Lihu Cao Hongtao Liu +2 位作者 Junyan Liu Hailong Geng Haotian Wei 《Engineering(科研)》 2019年第7期429-436,共8页
Abnormal oil casing pressure appeared in the process of test production of multiple Ultra-Deep Gas Wells in Tarim Basin. The super 13Cr oil pipe string was used to analyze the causes of pipe string failure in view of ... Abnormal oil casing pressure appeared in the process of test production of multiple Ultra-Deep Gas Wells in Tarim Basin. The super 13Cr oil pipe string was used to analyze the causes of pipe string failure in view of the oil casing channeling well during the test and blowout period. The construction process of the well was analyzed in detail. Combined with the review of the operation flow and the detection of fracture string material and fracture morphology, the causes of pipe string fracture were analyzed and calculated in detail. Through field investigation, analysis and calculation, it was found that the main cause of cracking of super 13Cr tubing in this well is the decrease of vibration natural frequency caused by excessive fluid velocity in pipe and too long span of pipe string. At the same time, the mixed failure of stress corrosion cracking and stress load interaction occurred in Cl&#8722;1 environment and other corrosion environments. 展开更多
关键词 ultra-deep WELL Gas WELL Pipe STRING Vibration Fatigue Corrosion
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A Study on the Effect of Low Calcium Ultra-fine Fly Ash as a Partial Sustainable Supplementary Material to Cement in Self-compacting Concrete 被引量:2
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作者 Adapala Sunny Suprakash Karthiyaini S 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第2期330-341,共12页
The aim and scope of the present study were to determine the efficacy of UFFA in evaluating the workability,static and dynamic stabilization properties,retention period,and slump loss of SCC systems in their fresh sta... The aim and scope of the present study were to determine the efficacy of UFFA in evaluating the workability,static and dynamic stabilization properties,retention period,and slump loss of SCC systems in their fresh state,as well as their compressive strength at various ages.Microstructure(SEM and XRD)of blended SCC systems were studied.Also,the thermogravimetry behavior of blended SCC specimens were researched.According to the evaluated results,incorporating up to 20%UFFA into fresh concrete improved its performance due to its engineered fine particle size and spherical geometry,both of which contribute to the enhancement of characteristics.Blends of 25%and 30%of UFFA show effect on the water-binder ratio and chemical enhancer dosage,resulting in a loss of homogeneity in fresh SCC systems.The reduced particle size,increased amorphous content,and increased surface area all contribute to the pozzolanic reactivity of the early and later ages,resulting in denser packing and thus an increase in compressive strength.The experimental results indicate that UFFA enhances the properties of SCC in both its fresh and hardened states,which can be attributed to the particles’fineness and their relative effect on SCC. 展开更多
关键词 ultra fine fly ash self-compacting concrete WORKABILITY SEGREGATION compressive strength microstructure TGA
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万米深井上部大尺寸井眼钻柱动力学特性研究 被引量:4
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作者 祝效华 李柯 +3 位作者 李文哲 贺明敏 佘朝毅 谭宾 《天然气工业》 EI CAS CSCD 北大核心 2024年第1期49-57,共9页
油气勘探已向更深、更复杂的超深层的万米勘探新领域推进,但上部大尺寸井眼给万米深井的钻井提出了巨大挑战:岩石硬和返速低导致钻速慢,大尺寸井眼内剧烈振动导致钻具裂纹多发,钻压小则钻速慢,钻压稍大则下部振动快速加剧从而导致大尺... 油气勘探已向更深、更复杂的超深层的万米勘探新领域推进,但上部大尺寸井眼给万米深井的钻井提出了巨大挑战:岩石硬和返速低导致钻速慢,大尺寸井眼内剧烈振动导致钻具裂纹多发,钻压小则钻速慢,钻压稍大则下部振动快速加剧从而导致大尺寸钻具使用寿命远低于预期。为此,在对比研究了深地川科1井(以下简称SDCK-1井)和毗邻8000 m超深井上部井段钻柱振动问题基础上,基于全井钻柱系统动力学模型和数值仿真方法,针对性研究了大尺寸井眼中的钻柱动力学特性。研究结果表明:①井眼尺寸越大,钻头和下部钻具的振动越剧烈,SDCK-1井二开大尺寸井眼与邻井中等尺寸井眼相比(井深500 m处),其钻头及下部钻具振动强度均值分别增加了48.0%和41.5%,比SDCK-1井三开中等尺寸3000 m井深的钻头及下部钻具振动强度均值分别高了29.0%和2.9%;②相同井眼尺寸和岩石特性情况下,下部钻具组合比钻柱整体长度对钻头振动的影响更大,优化下部钻具组合能够明显改善钻头振动,保护钻头,同时还可以提高钻头破岩能量利用效率实现钻井提速;③在大尺寸井眼中钻头破岩激励向上传播,横向振动衰减慢于轴向振动衰减,大尺寸钻头扭矩更大且钻压和扭矩波动更加明显,因此从保护下部钻具的角度出发,大尺寸井眼钻具组合对抑制横振更加有效;④大尺寸井眼中下部钻具弯矩和弯矩波动更大,现场频繁出现的钻具裂纹除受控于整体振动强度较大以外,交变弯矩是裂纹发生的重要原因。结论认为,该研究成果揭示了超深井大尺寸井眼中钻柱的动力学特性,指出了应着重控制横振和交变弯矩,该认识可以为超深井上部大尺寸井眼钻井提供技术指导。 展开更多
关键词 超深井 科探井 SDCK-1井 大尺寸井眼 钻头振动 钻柱动力学 钻具裂纹
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基于管柱动力学的特深井通井组合刚度评价方法与应用 被引量:3
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作者 祝效华 李文哲 +5 位作者 李柯 陈力力 孟鐾桥 沈欣宇 罗伟 贺明敏 《钻采工艺》 CAS 北大核心 2024年第2期51-58,共8页
我国特深井钻井正处于快速发展阶段,受井眼尺寸大和深度深的影响,钻井过程中极易出现微井斜、扩径缩径和井壁台阶等,导致套管下入困难,因此通井钻具组合评价尤为重要。目前,现场使用的评价方法常忽略了管柱下入过程中与井壁的碰撞和变形... 我国特深井钻井正处于快速发展阶段,受井眼尺寸大和深度深的影响,钻井过程中极易出现微井斜、扩径缩径和井壁台阶等,导致套管下入困难,因此通井钻具组合评价尤为重要。目前,现场使用的评价方法常忽略了管柱下入过程中与井壁的碰撞和变形,导致通井效果时好时坏。为了辅助现场施工,文章基于全井管柱动力学模型和HHT-α数值计算方法提出了一种能够模拟管柱下入的动态过程的通井钻具组合的评价方法,该方法考虑了实测井眼轨迹、井眼扩大率和下入阻力等要素。通过某特深井三开下套管前的钻具组合进行实例计算分析,表明井眼扩大率和套管串下入阻力对通井能力和套管下入影响较大,当井眼扩大率较小且套管串下入阻力较大时,需要使用刚度较大的多扶正器通井钻具组合。本方法可以实现实测井况条件下比较精准的刚度对比模拟,也成功指导了案例井?486 mm套管的安全下入。 展开更多
关键词 特深井 通井钻具组合 管柱动力学模型 刚度比 井眼扩大率 下入阻力
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Optimum Design and Global Analysis of Flexible Jumper for An Innovative Subsurface Production System in Ultra-Deep Water 被引量:5
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作者 黄一 甄兴伟 +1 位作者 张崎 王文华 《China Ocean Engineering》 SCIE EI CSCD 2014年第2期239-247,共9页
The study focuses on the flexible jumper issue of Subsurface Tension Leg Production (STLP) system concept, which is considered as a competing alternative system to support well completion devices and rigid risers in... The study focuses on the flexible jumper issue of Subsurface Tension Leg Production (STLP) system concept, which is considered as a competing alternative system to support well completion devices and rigid risers in ultra-deep water for offshore petroleum production. The paper presents analytical and numerical approaches for the optimum design and global analysis of the flexible jumper. Criteria using catenary concept are developed to define the critical length for optimum design. Based on the criteria, detailed hydrodynamic analyses including quasi-static analysis, modal analysis, and dynamic analysis are performed. Modal analysis with respect to the quasi-static analysis shows that the existence of resonant modes requires special consideration. The results of dynamic analysis confirm the effectiveness of the de-coupled effect from the jumper on STLP system. The approaches developed in the study also have wide application prospect in reference to the optimum design and analysis of any Hybrid Riser (HR) concept. 展开更多
关键词 subsurface production system flexible jumper dynamic analysis ultra-deep water
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Theoretical Progress and Key Technologies of Onshore Ultra-Deep Oil/Gas Exploration 被引量:27
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作者 Xusheng Guo Dongfeng Hu +5 位作者 Yuping Li Jinbao Duan Xuefeng Zhang Xiaojun Fan Hua Duan Wencheng Li 《Engineering》 SCIE EI 2019年第3期458-470,共13页
Oil/gas exploration around the world has extended into deep and ultra-deep strata because it is increasingly difficult to find new large-scale oil/gas reservoirs in shallow–middle buried strata. In recent years, Chin... Oil/gas exploration around the world has extended into deep and ultra-deep strata because it is increasingly difficult to find new large-scale oil/gas reservoirs in shallow–middle buried strata. In recent years, China has made remarkable achievements in oil/gas exploration in ultra-deep areas including carbonate and clastic reservoirs. Some (ultra) large-scale oil and gas fields have been discovered. The oil/gas accumulation mechanisms and key technologies of oil/gas reservoir exploration and development are summarized in this study in order to share China’s experiences. Ultra-deep oil/gas originates from numerous sources of hydrocarbons and multiphase charging. Liquid hydrocarbons can form in ultradeep layers due to low geothermal gradients or overpressures, and the natural gas composition in ultra-deep areas is complicated by the reactions between deep hydrocarbons, water, and rock or by the addition of mantle- or crust-sourced gases. These oils/gases are mainly stored in the original highenergy reef/shoal complexes or in sand body sediments. They usually have high original porosity. Secondary pores are often developed by dissolution, dolomitization, and fracturing in the late stage. The early pores have been preserved by retentive diageneses such as the early charging of hydrocarbons. Oil/gas accumulation in ultra-deep areas generally has the characteristics of near-source accumulation and sustained preservation. The effective exploration and development of ultra-deep oil/gas reservoirs depend on the support of key technologies. Use of the latest technologies such as seismic signal acquisition and processing, low porosity and permeability zone prediction, and gas–water identification has enabled the discovery of ultra-deep oil/gas resources. In addition, advanced technologies for drilling, completion, and oil/gas testing have ensured the effective development of these fields. 展开更多
关键词 Oil/gas EXPLORATION ultra-deep sources Reservoir Petroleum accumulation EXPLORATION and EXPLOITATION technologies
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增效型无土相仿生油基钻井液技术的研究与应用 被引量:3
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作者 蒋官澄 黄胜铭 +3 位作者 侯博 孟凡金 屈艳平 王浩 《钻采工艺》 CAS 北大核心 2024年第2期93-103,共11页
针对深井超深井钻井过程中钻遇高温高压、井壁失稳及井下复杂情况的难题,基于仿生学、超分子化学以及岩石表面润湿性理论,通过优选仿生增效剂、仿生提切剂及仿生降滤失剂,配套相关处理剂,最终形成了一套适用于深井、超深井地层钻探的增... 针对深井超深井钻井过程中钻遇高温高压、井壁失稳及井下复杂情况的难题,基于仿生学、超分子化学以及岩石表面润湿性理论,通过优选仿生增效剂、仿生提切剂及仿生降滤失剂,配套相关处理剂,最终形成了一套适用于深井、超深井地层钻探的增效型无土相仿生油基钻井液体系。研究发现,建立的增效型无土相仿生油基钻井液体系可抗220℃高温,配制密度为2.4 g/cm^(3),破乳电压大于400 V,高温高压滤失量为3.2 mL,人造岩心在该体系中220℃下老化后的抗压强度达到7.1 MPa,平均渗透率恢复值为93.9%。现场应用情况表明,体系流变性能稳定,平均机械钻速比邻井提高16%,平均井径扩大率仅为1.25%,可有效解决深井超深井钻井过程中出现的井壁失稳难题,为我国深井超深井的钻探提供了技术保障。 展开更多
关键词 深井超深井 油基钻井液 无土相 仿生 增效
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Parametric Study on the Behavior of An Innovative Subsurface Tension Leg Platform in Ultra-Deep Water 被引量:5
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作者 ZHEN Xing-wei HUANG Yi 《China Ocean Engineering》 SCIE EI CSCD 2017年第5期589-597,共9页
This study focuses on a new technology of Subsurface Tension Leg Platform (STLP), which utilizes the shallow- water rated well completion equipment and technology for the development of large oil and gas fields in u... This study focuses on a new technology of Subsurface Tension Leg Platform (STLP), which utilizes the shallow- water rated well completion equipment and technology for the development of large oil and gas fields in ultra-deep water (UDW). Thus, the STLP concept offers attractive advantages over conventional field development concepts. STLP is basically a pre-installed Subsurface Sea-star Platform (SSP), which supports rigid risers and shallow-water rated well completion equipment. The paper details the results of the parametric study on the behavior of STLP at a water depth of 3000 m. At first, a general description of the STLP configuration and working principle is introduced. Then, the numerical models for the global analysis of the STLP in waves and current are presented. After that, extensive parametric studies are carried out with regarding to SSP/tethers system analysis, global dynamic analysis and riser interference analysis. Critical points are addressed on the mooring pattern and riser arrangement under the influence of ocean current, to ensure that the requirements on SSP stability and riser interference are well satisfied. Finally, conclusions and discussions are made. The results indicate that STLP is a competitive well and riser solution in up to 3000 m water depth for offshore petroleum production. 展开更多
关键词 subsurface tension leg platform parametric study global behavior ultra-deep water
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Parametric Dimensional Analysis on the Structural Response of An Innovative Subsurface Tension Leg Platform in Ultra-Deep Water 被引量:4
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作者 ZHEN Xing-wei WU Jia-hao +2 位作者 HUANG Yi HAN Yue YAO Jin-jiang 《China Ocean Engineering》 SCIE EI CSCD 2018年第4期482-489,共8页
The innovative Subsurface Tension Leg Platform(STLP), which is designed to be located below Mean Water Level(M.W.L) to minimize direct wave loading and mitigate the effect of strong surface currents, is considered as ... The innovative Subsurface Tension Leg Platform(STLP), which is designed to be located below Mean Water Level(M.W.L) to minimize direct wave loading and mitigate the effect of strong surface currents, is considered as a competitive alternative system to support shallow-water rated well completion equipment and rigid risers for large ultra-deep water oil field development. A detailed description of the design philosophy of STLP has been published in the series of papers and patents. Nonetheless, design uncertainties arise as limited understanding of various parameters effects on the structural response of STLP, pertaining to the environmental loading, structural properties and hydrodynamic characteristics. This paper focuses on providing quantitative methodology on how each parameter affects the structural response of STLP, which will facilitate establishing the unique design criteria as regards to STLP. Firstly, the entire list of dimensionless groups of input and output parameters is proposed based on VaschyBuckingham theory. Then, numerical models are built and a series of numerical tests are carried out for validating the obtained dimensionless groups. On this basis, the calculation results of a great quantity of parametric studies on the structural response of STLP are presented and discussed in detail. Further, empirical formulae for predicting STLP response are derived through nonlinear regression analysis. Finally, conclusions and discussions are made. It has been demonstrated that the study provides a methodology for better control of key parameters and lays the foundation for optimal design of STLP. The obtained conclusions also have wide ranging applicability in reference to the engineering design and design analysis aspects of deepwater buoy supporting installations, such as Grouped SLOR or TLR system. 展开更多
关键词 subsurface tension leg platform structural response dimensional analysis ultra-deep water
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Possible Connections between Seasons and Ultra-Deep Earthquakes Worldwide 被引量:2
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作者 Marilia Hagen A. Azevedo 《Natural Science》 2018年第7期288-302,共15页
The aim of this investigation is to find possible changes in ultra-deep earthquakes (UDQ) during different seasons of the year. In the acquisition of data for our previous work we observed an inexplicable pattern of g... The aim of this investigation is to find possible changes in ultra-deep earthquakes (UDQ) during different seasons of the year. In the acquisition of data for our previous work we observed an inexplicable pattern of growth of ultra-deep tremors (UDQ) during the studied period. Apparently, there is no viable explanation for growth occurring at such a level, presumably in the asthenosphere. Current research and theories developed for the inner layers of the Earth do not explain such variations. Therefore, a possible explanation would be in external factors such as the seasons of the year, which are determined by changes in the Earth’s axial tilt, and therefore the portion of the earth that is angled toward the sun. This paper focuses exclusively on UDQ events. To simplify the calculations, we consider four main locations;this includes one more region than our previous paper but includes only UDQ data. The results showed that during spring and autumn UDQ events grew slightly in both Northern and Southern Hemispheres. It is also suggested that a contributor to UDQ events is friction from the subducting lithosphere against the continental plates. 展开更多
关键词 Sun MOON Earth ultra-deep Quakes SEASONS
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Xpert MTB/RIF Ultra快速诊断涂阴肺结核的临床价值 被引量:9
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作者 丁彩红 王余余 +3 位作者 王庆 高绪胜 解丹 熊瑜 《解放军医学杂志》 CAS CSCD 北大核心 2023年第7期761-767,共7页
目的评估超敏结核分枝杆菌和利福平耐药基因检测(XpertUltra)方案检测痰液及支气管肺泡灌洗液(BALF)标本在涂阴肺结核患者中早期、快速诊断的价值。方法选择2020年5月-2021年12月在山东省公共卫生临床中心就诊的痰涂片阴性疑似肺结核患... 目的评估超敏结核分枝杆菌和利福平耐药基因检测(XpertUltra)方案检测痰液及支气管肺泡灌洗液(BALF)标本在涂阴肺结核患者中早期、快速诊断的价值。方法选择2020年5月-2021年12月在山东省公共卫生临床中心就诊的痰涂片阴性疑似肺结核患者93例,其中临床诊断为涂阴肺结核57例,非肺结核36例。收集所有患者的痰液及BALF标本,分别采用Xpert Ultra、GeneXpert MTB/RIF(Xpert)、BACTEC MGIT 960培养(MGIT 960培养)进行检测。以临床诊断为参考标准,评价3种检测方案及相互联合检测痰液及BALF标本时诊断涂阴肺结核的敏感度、特异度及符合率。结果以临床诊断结果为参考标准,Xpert Ultra检测痰液标本对涂阴肺结核诊断的敏感度明显高于Xpert[56.14%(32/57)vs.36.84%(21/57),P=0.03]和MGIT960培养[56.14%(32/57)vs.33.33%(19/57),P=0.014];Xpert Ultra检测BALF标本对涂阴肺结核诊断的敏感度明显高于Xpert[75.44%(43/57)vs.56.14%(32/57),P=0.030]和MGIT960培养[75.44%(43/57)vs.38.60%(22/57),P<0.01]。3种检测方案及相互联合检测痰液标本诊断涂阴肺结核,受试者工作特征(ROC)曲线下面积(AUC)依次为:三者联合(0.807)>Xpert Ultra+Xpert(0.798)>Xpert Ultra+MGIT 960培养(0.789)>Xpert Ultra(0.781)>Xpert(0.684)>MGIT 960培养(0.667);检测BALF标本,AUC依次为:三者联合(0.895)=Xpert Ultra+Xpert(0.895)>XpertUltra+MGIT960培养(0.877)=XpertUltra(0.877)>Xpert(0.781)>MGIT960培养(0.693)。3种检测方案均未在入组患者中检测到利福平耐药。结论Xpert Ultra对早期、快速诊断涂阴肺结核具有较高的临床应用价值;其检测BALF的敏感度高于痰液标本,建议优先选择BALF标本。 展开更多
关键词 超敏结核分枝杆菌和利福平耐药基因检测 涂阴肺结核 分子诊断技术 耐药 早期诊断
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