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Evaluation of natural gas hydrate resources in the South China Sea using a new genetic analogy method

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Petroleum Science 2022年第1期19卷 48-57页

作者： xiao-han liu Tao Hu Xiong-Qi Pang Zhi Xu Tong Wang Xing-Wen Zhang En-Ze Wang Zhuo-Ya Wu State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing 102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China School of Earth&Space Sciences Peking UniversityBeijing100871China Research Institute of Petroleum Exploration&Development CNPCBeijing100083China

Natural gas hydrate(NGH)has attracted much attention as a new alternative energy ***,evaluations of global NGH resources in the past few decades have casted a decreasing trend,where the estimate as of today is less than one ten-thousandth of the estimate forty years *** NGH researches in China started relatively late,but achievements have been made in the South China Sea(SCS)in the past two ***-five studies had been carried out to evaluate NGH resource,and results showed a flat trend,ranging from 60 to 90 billion tons of oil equivalent,which was 2-3 times of the evaluation results of technical recoverable oil and gas resources in the *** big difference is that the previous 35 group of NGH resource evaluations for the SCS only refers to the prospective gas resource with low grade level and high uncertainty,which cannot be used to guide exploration or researches on development *** on the analogy with the genetic mechanism of conventional oil and gas resources,this study adopts the newly proposed genetic method and geological analogy method to evaluate the NGH *** show that the conventional oil and gas resources are 346.29×10^(8)t,the volume of NGH and free dynamic field are 25.19×10^(4)km^(3) and(2.05-2.48)×10^(6)km^(3),and the total amount of in-situ NGH resources in the SCS is about(4.47-6.02)×10^(12)m^(3).It is considered that the resource of hydrate should not exceed that of conventional oil and gas,so it is 30 times lower than the previous *** study provides a more reliable geological basis for further NGH exploration and development.

关键词： South China Sea Natural gas hydrate Natural gas hydrate resources Conventional oil and gas resources Genetic method Analogy method

Distribution and resource evaluation of natural gas hydrate in South China sea by combing phase equilibrium mechanism and volumetric method

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Petroleum Science 2022年第1期19卷 26-36页

作者： Tong Wang Tao Hu Xiong-Qi Pang Xing-Wen Zhang xiao-han liu Zhi Xu En-Ze Wang Zhuo-Ya Wu State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China School of Earth&Space Sciences Peking UniversityBeijing100871China Research Institute of Petroleum Exploration and Development PetroChina Company LimitedBeijing100083China

China Geological Survey conducted the second trial production of natural gas hydrate(NGH)in the Shenhu Area in South China Sea(SCS)from 2019 to *** with the first trial production in 2017,the second trial showed significantly increased daily gas production and total gas production,and removed some technical obstacles for large-scale NGH resource developments in the ***,current NGH resource evaluation in the SCS is still at the stage of prospective gas content assessment,which is unable to guide further NGH exploration and *** study utilized the hydrate phase balance to delineate the NGH distribution range and effective thickness and volumetric method to evaluate NGH *** on the latest exploration and production data from the Shenhu Area,Monte Carlo simulation was performed to calculate the NGH resource amount with different *** assuming a 50%cumulative probability,the in-situ NGH resources in the SCS was estimated to be11.7×10^(12)m^(3) and the recoverable NGH resources was 2.8×10^(12)m^(3).These results will provide a more reliable resource basis for China to formulate comprehensive development strategies for oil and gas exploration in the SCS.

关键词： South China Sea Oil and gas resource Natural gas hydrate In-situ resource Recoverable resources

Nocturnal hypertension and riser pattern are associated with heart failure rehospitalization in patients with heart failure with preserved ejection fraction

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Journal of Geriatric Cardiology 2023年第6期20卷 448-458页

作者： Gang HUANG xiao-han liu Yue ZhanG Yu-Xin ZHU Yun HE Tian-Bo WANG Zhen ZhanG Jun-Bo XU Department of Cardiology the Third People’s Hospital of ChengduSichuanChina Cardiovascular Disease Research Institute of Chengdu SichuanChina Affiliated Hospital of Southwest Jiaotong University SichuanChina The Second Affiliated Chengdu Clinical College of Chongqing Medical University SichuanChina

BACKGROUND Nocturnal hypertension is reported as a risk factor for cardiovascular *** study aimed to explore the potential association between nocturnal hypertension and heart failure(HF)rehospitalization in patients with HF with preserved ejection fraction(HFpEF).METHODS A total of 538 patients with HFpEF from May 2018 to December 2021 were consequently recruited in this study and followed up until they were readmitted for HF or the end of this *** regression analysis was used to reveal the potential association between nighttime blood pressure(BP)levels,nocturnal hypertension and nocturnal BP patterns and HF ***-Meier curve was used to assess the cumulative event-free survival rate between *** There were 537 patients with HFpEF were included in the final *** mean age of the study population was 77.14±8.68 years,and 41.2% of patients were *** a median follow-up duration of 10.93(4.19–21.13)months,176 patients(32.7%)with HFpEF were readmitted for *** regression analysis had revealed that nighttime systolic BP level[hazards ratio(HR)=1.018,95%CI:1.008–1.028,P=0.001],nighttime diastolic BP level(HR=1.024,95%CI:1.007–1.042,P=0.007),nocturnal hypertension(HR=1.688,95%CI:1.229–2.317,P=0.001)were associated with HF ***-Meier analysis had demonstrated that patients with nocturnal hypertension had significantly lower event-free survival rate(log-rank Phan those with a dipper *** findings were also confirmed in patients with HFpEF and *** Nighttime BP levels,nocturnal hypertension and a riser pattern are independently associated with HF rehospitalization in patients with HFpEF,and prominently in patients with HFpEF and *** controlled nighttime BP levels should be empha

关键词： pattern fraction admitted

Evaluation of natural gas hydrate resources in the South China Sea by combining volumetric and trend-analysis methods

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Petroleum Science 2022年第1期19卷 37-47页

作者： Xing-Wen Zhang Tao Hu Xiong-Qi Pang Yao Hu Tong Wang En-Ze Wang Zhi Xu xiao-han liu Zhuo-Ya Wu Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing 102249China College of Geosciences China University of Petroleum(Beijing)Beijing 102249China CNOOC International Limited Beijing 100029China School of Earth&Space Sciences Peking UniversityBeijing 100871China Research Institute of Petroleum Exploration and Development PetroChina Company LimitedBeijing 100083China

Natural gas hydrate(NGH),considered as a type of premium energy alternative to conventional hydrocarbons,has been broadly *** estimate of the total NGH resources in the world has decreased by more than 90%since the first evaluation in *** and geophysical conditions of the South China Sea(SCS)are favorable for the formation of NGH,which has been proved by drilling results up to *** recoverability of the NGH in the SCS has been confirmed by the production tests using both vertical and horizontal *** 2001,35 estimates of NGH resources in the SCS have been made,with relatively stable results varying between 600 and 900×109 ton oil *** these estimations,the volumetric method was commonly adopted,but the geological conditions,the migration-accumulation mechanisms of NGH,and the practical recoverability were not *** estimates cannot be regarded as evaluated resources according to the international resource evaluation standards,but are at most about prospective gas content of NGH,thus inefficient for guiding explorations and *** solve these problems,this study divides the past NGH surveys in the SCS into seven stages,acquires key geological parameters of every stage based on previous studies and analogy with other areas,evaluates the NGH resources of these seven stages by using the volumetric method,then adopts a new trend-analysis method to simulate the downward trend of these estimates,and finally predicts the NGH resources in the SCS at 2025 and *** downward trend is because of the continuous improvement of NGH understanding over time,which is consistent with the trend of global NGH *** the present stage(from 2019 to 2021),the average technically recoverable resource(ATRR)is 7.0×10^(12)m^(3),and the estimates of 2025 and 2030 ATRR are 6.46×10^(12)m^(3) and 4.01×10^(12)m^(3)respectively,with a difference of less than 40%.Therefore,it can be inferred that the ATRR of NGH in the SCS is between

关键词： Resource evaluation Natural gas hydrates The South China Sea Volumetric method Trend-analysis method

Layered oxide cathodes for sodium-ion batteries:microstructure design,local chemistry and structural unit

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Science China Chemistry 2024年第1期67卷 191-213页

作者： Ling-Yi Kong han-xiao liu Yan-Fang Zhu Jia-Yang Li Yu Su Hong-Wei Li Hai-Yan Hu Yi-Feng liu Ming-Jing Yang Zhuang-Chun Jian Xin-Bei Jia Shu-Lei Chou Yao xiao Institute for Carbon Neutralization College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325035China

Because of the low price and abundant reserves of sodium compared with lithium,the research of sodium-ion batteries(SIBs)in the field of large-scale energy storage has returned to the research *** oxides distinguish themselves from the mains cathode materials of SIBs owing to their advantages such as high specific capacity,simple synthesis route,and environmental ***,the commercial development of the layered oxides is limited by sluggish kinetics,complex phase transition and poor air *** on the research ideas from macro-to micro-scale,this review systematically summarizes the current optimization strategies of sodium-ion layered oxide cathodes(SLOC)from different dimensions:microstructure design,local chemistry regulation and structural unit *** the dimension of microstructure design,the various structures such as the microspheres,nanoplates,nanowires and exposed active facets are prepared to improve the slow kinetics and electrochemical ***,from the view of local chemistry regulation by chemical element substitution,the intrinsic electron/ion properties of SLOC have been enhanced to strengthen the structural ***,the optimization idea of endeavors to regulate the physical and chemical properties of cathode materials essentially is put forward from the dimension of structural unit *** opinions and strategies proposed in this review will provide some inspirations for the design of new SLOC in the future.

关键词： sodium-ion batteries layered oxide cathodes microstructure design local chemistry structural unit

Research progress and challenges of natural gas hydrate resource evaluation in the South China Sea

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Petroleum Science 2022年第1期19卷 13-25页

作者： Zhi Xu Tao Hu Xiong-Qi Pang En-Ze Wang xiao-han liu Zhuo-Ya Wu Di Chen Chang-Rong Li Xing-Wen Zhang Tong Wang State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China School of Earth&Space Sciences Peking UniversityBeijing100871China Research Institute of Petroleum Exploration&Development CNPCBeijing100083China

As an efficient clean energy,natural gas hydrate(NGH)has become a hot topic in recent ***1990 s,China has made great achievements and progress in NGH exploration in the South China Sea(SCS),including determination of the favorable distribution areas and favorable strata thickness,identification of the dual source for accumulation,evaluation of the prospective gas contents,verification of the widespread existence,and confirmation of the technical recoverability of NGH ***,there are three major challenges in the NGH ***,all the 24 national key and major projects in the SCS focused on trial production engineering and geological engineering in the past 20 years,while 8 of the 10 international NGH research projects focused on resource ***,resource evaluation methods are outdated and some parameter selection are ***,the existing resource evaluation results are low-level with a great uncertainty,and cannot be used to guide NGH exploration and production or strategic *** improve the evaluation of NGH resources in the SCS,future researches should focus on four aspects:(1)improve the research on the criterion of the objective existence of NGH and the method of prediction and evaluation;(2)apply new theories and methods from the global NGH research;(3)boost the research on the difference and correlation of the conditions of hydrocarbon migration and accumulation in different basins;(4)innovate the theory and method of NGH resource potential evaluation.

关键词： South China Sea Natural gas hydrate Oil and gas resource evaluation Comprehensive exploration of oil and gas Oil and gas development strategy

Key factors controlling shale oil enrichment in saline lacustrine rift basin:implications from two shale oil wells in Dongpu Depression,Bohai Bay Basin

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Petroleum Science 2021年第3期18卷 687-711页

作者： Tao Hu Xiong-Qi Pang Fu-Jie Jiang Qi-Feng Wang Guan-Yun Wu xiao-han liu Shu Jiang Chang-Rong Li Tian-Wu Xu Yuan-Yuan Chen State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China College of Geosciences China University of PetroleumBeijing 102249China Energy&Geoscience Institute University of UtahSalt Lake CityUT 84108USA Research Institute of Exploration and Development Zhongyuan Oilfeld CompanySINOPECPuyangHenan 457001China

Comparative analyses of petroleum generation potential,reservoir volume,frackability,and oil mobility were conducted on 102 shale cores from the Dongpu *** show the shale has high organic matter contents composed of oil-prone type I and type II kerogens within the oil *** types of pores and fractures exist in the shale,with a porosity of up to 14.9%.The shale has high brittle mineral contents,extensive fractures,and high potential for oil mobility due to high seepage capacity and *** the petroleum generation potential of the shale at Well PS18-8 is relatively greater than that at Well PS18-1,oil content of the latter is greater due to the greater *** porosity and fracture density observed in Well PS18-1 are greater and more conducive to shale oil *** the shales in Wells PS18-1 and PS18-8 have similar brittle mineral contents,the former is more favorable for anthropogenic fracturing due to a higher preexisting fracture ***,the shale at Well PS18-1 has a higher seepage capacity and overpressure and therefore a higher oil *** fracture density and overpressure play key roles in shale oil enrichment.

关键词： Petroleum generation potential Reservoir volume Frackability Oil mobility Shale oil enrichment Dongpu Depression Saline lacustrine rift basin

The effects of PMD and PDL on the performance of OOK and DPSK systems

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Optoelectronics Letters 2008年第1期4卷 38-41页

作者： TIAN xiao-xing, liu han-kui , QIU Jun-cai, and YUAN Fu-lai College of Physics and Electronics Information, China West Normal University, Nanchong 637002, China College of Physics and Electronics Information China West Normal University Nanchong China

Using multiple importance sampling (MIS) technique, the optical communication system performance affected by polariza- tion-mode dispersion (PMD) and polarization-dependent loss (PDL) is simulated numerically. The power penalties and system outage probabilities are obtained for optical communication systems with on-off keying (OOK) or differential phase shift keying (DPSK) modulation. The simulation results show that DPSK always performs better than OOK. When the system has moderate PDL (about 1.5 dB), it is necessary to compensate effectively the fiber PMD in order to enhance the system tolerance to the PMD and PDL. However, the efficiency of PMD compensation will degrade rapidly when the PMD of the whole optical link drops into the low value.

关键词：开关键控系统微分相移键控系统偏振模式散射偏振损失光纤通信

Posterior Reduction and Monosegmental Fusion with Intraoperative Three-dimensional Navigation System in the Treatment of High-grade Developmental Spondylolisthesis

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Chinese Medical Journal 2015年第7期128卷 865-870页

作者： Wei Tian xiao-Guang han Bo liu Ya-Jun liu Da He Qiang Yuan Yun-Feng Xu Department of Spine Surgery Beijing Jishuitan Hospital Beijing 100035 China

Background： The treatment of high-grade developmental spondylolisthesis （HGDS） is still challenging and controversial. In this study, we investigated the efficacy of the posterior reduction and monosegmental fusion assisted by intraoperative three-dimensional （3D） navigation system in managing the HGDS. Methods： Thirteen consecutive HGDS patients were treated with posterior decompression, reduction and monosegmental fusion ofL5/S1, assisted by intraoperative 3D navigation system. The clinical and radiographic outcomes were evaluated, with a minimum follow-up of 2 years. The differences between the pre- and post-operative measures were statistically analyzed using a two-tailed, paired t-test. Results： At most recent follow-up, 12 patients were pain-free. Only l patient had moderate pain, There were no permanent neurological complications or pseudarthrosis. The magnetic resonance imaging showed that there was no obvious disc degeneration in the adjacent segment. All radiographic parameters were improved. Mean slippage improved from 63.2% before surgery to 12.2% after surgery and 11.0% at latest follow-up. Lumbar lordosis changed from preoperative 34.9 ± 13.3° to postoperative 50.4 ±9.9°, and 49.3 ± 7.8° at last follow-up. L5 incidence improved from 71.0 ± 11.3° to 54.0 ± 1 1.9° and did not change significantly at the last follow-up 53.±1 15.4°. While pelvic incidence remained unchanged, sacral slip significantly decreased from preoperative 32.7± 12.5° to postoperative 42.6 ± 9.8°and remained constant to the last follow-up 44.4 ± 6.9°. Pelvic tilt significantly decreased from 38.4±12.5° to 30.9± 8.1° and remained unchanged at the last fbllow-up 28.1± 11.2°. Conclusions： Posterior reduction and monosegmental fusion of L5/S1 assisted by intraoperative 3D navigation are an effective technique for managing high-grade dysplastic spondylolisthesis. A complete reduction of local deformity and excellent correction of overall sagittal balance can be achieved.

关键词： High-grade Developmental Spondylolisthesis Intraoperative Three-dimensional Navigation Neurological Complication Reduction: Spondylolisthesis