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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

Effect of secondary air on NO emission in a 440 t/h circulating fluidized bed boiler based on CPFD method

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Particuology 2023年第12期83卷 18-31页

作者： Hongpeng liu Haiwen Sun Ye Bi Chunxia Jia Lei Zhang yanlong li Hong Qin Qing Wang Engineering Research Centre of Oil Shale Comprehensive Utilization Ministry of EducationSchool of Energy and Power EngineeringNortheast Electric Power UniversityJilin132012China Department of Chemical&Biological Engineering University of British ColumbiaVancouverV6T1Z3Canada Northeast Branch of Huadian Electric Power Research Institute Co. LtdShenyang110000China

The 440 t/h circulating fluidized bed boiler was numerically simulated by the Computational Particle Fluid Dynamics(CPFD)method.The combustion characteristics of circulating fluidized bed boiler and the effect of secondary air on NO emission were investigated.The full-scale three-dimensional model of a 440 t/h circulating fluidized bed boiler was established.The rationality of the grid was validated by the experimental data of material layer resistance.The accuracy of the simulation was validated by measuring the temperature of each measuring point in the dense phase area.The combustion conditions in the furnace under different setting modes were simulated.The effects of secondary air rates on NO formation in fluidized bed were predicted.The results show that when the secondary air rate increases to 27%,the proper secondary air rate has a positive effect on the inhibition of NO generation,and the proper strengthening of the central air supply will improve the permeability of the secondary air and make the combustion more uniform and stable.When the secondary air rate increases to 33%,excessive improvement of air classification and central air distribution will affect the stability of circulating fluidized bed operation.Therefore,air classification and strengthening of central air supply can be used together to inhibit the generation of NO.

关键词： Circulatingfluidized bed Low nitrogen combustion Computational particlefluid dynamics (CPFD) Numerical simulation Secondary air

Hydrate formation and distribution within unconsolidated sediment:Insights from laboratory electrical resistivity tomography

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Acta Oceanologica Sinica 2022年第9期41卷 127-136页

作者： yanlong li Nengyou Wu Changling liu Qiang Chen Fulong Ning Shuoshi Wang Gaowei Hu Deli Gao Key Laboratory of Gas Hydrate of Ministry of Natural Resources Qingdao Institute of Marine GeologyQingdao266237China Laboratory for Marine Mineral Resources Pilot National Laboratory of Marine Science and Technology(Qingdao)Qingdao266237China Faculty of Engineering China University of Geosciences(Wuhan)Wuhan430074China School of Chemical Biological&Materials EngineeringUniversity of OklahomaNormanOklahoma73019USA MOE Key Laboratory of Petroleum Engineering(China University of Petroleum) Beijing102249China

Laboratory visual detection on the hydrate accumulation process provides an effective and low-cost method to uncover hydrate accumulation mechanisms in nature.However,the spatial hydrate distribution and its dynamic evolutionary behaviors are still not fully understood due to the lack of methods and experimental systems.Toward this goal,we built a two-dimensional electrical resistivity tomography(ERT)apparatus capable of measuring spatial and temporal characteristics of hydrate-bearing porous media.Beach sand(0.05–0.85 mm)was used to form artificial methane hydrate-bearing sediment.The experiments were conducted at 1°C under excess water conditions and the ERT data were acquired and analyzed.This study demonstrates the utility of the ERT method for hydrate mapping in laboratory-scale.The results indicate that the average electrical conductivity decreases nonlinearly with the formation of the hydrate.At some special time-intervals,the average conductivity fluctuates within a certain scope.The plane conductivity fields evolve heterogeneously and the local preferential hydrate-forming positions alternate throughout the experimental duration.We speculate that the combination of hydrate formation itself and salt-removal effect plays a dominant role in the spatial and temporal hydrate distribution,as well as geophysical parameters changing behaviors during hydrate accumulation.

关键词： natural gas hydrate electrical resistivity electrical resistivity tomography accumulation mechanism electrical conductivity

Variations in growth traits and wood physicochemical properties among Pinus koraiensis families in Northeast China

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Journal of Forestry Research 2022年第5期33卷 1637-1648页

作者： Qinhui Zhang Xiaona Pei Xianbo Lu Chunli Zhao Guangzhi Dong Wanling Shi liankui Wang yanlong li Xiyang Zhao Mulualem Tigabu College of Forestry and Grassland Jilin Agricultural UniversityChangchun 130118People’s Republic of China State Key Laboratory of Tree Genetics and Breeding Northeast Forestry UniversityHarbin 150040People’s Republic of China Sanchazi Forestry Bureau of Jilin Province Baishan 134702People’s Republic of China Southern Swedish Forest Research Centre Swedish University of Agricultural SciencesPO Box 4923053 AlnarpSweden

This study aimed to explore and improve the different economic values of Pinus koraiensis(Siebold and Zucc.)by examining the variations in 6 growth traits and 9 physicochemical wood properties among 53 P.koraiensis half-sib families.Growth traits assessed included height,diameter at breast height,volume,degree of stem straight-ness,stem form,and branch number per node,while wood properties assessed included density,fiber length and width,fiber length to width ratio,and cellulose,hemicel-lulose,holocellulose,lignin,and ash contents.Except for degree of stem straightness and branch number per node,all other traits exhibited highly significant variations(Plies.The coefficients of variation ranged from 5.3(stem form)to 66.7%(ash content),whereas,the herit-ability ranged from 0.136(degree of stem straightness)to 0.962(ash content).Significant correlations were observed among growth traits and wood physicochemical properties.Principal component analysis identified four distinct groups representing growth traits,wood chemical and physical properties,and stem form traits.Multi-trait comprehensive evaluation identified three groups of elite families based on breeding objectives,including rapid growth,improved timber production for building and furniture materials,and pulpwood production.These specific families should be used to establish new plantations.

关键词： Growth and wood traits Pinus koraiensis Principal component analysis Family selection Economic benefits

Experimental study on sand production and coupling response of silty hydrate reservoir with different contents of fine clay during depressurization

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Petroleum 2023年第1期9卷 72-82页

作者： Xiangyu Fang Dianheng Yang Fulong Ning linjie Wang Zhichao liu Yanjiang Yu Wenwei Xie Hongfeng Lu yanlong li Meng Xu Faculty of Engineering China University of GeosciencesWuhan430074China Anhui Nuclear Exploration Technology Central Institute Wuhu241000China National Center for International Research on Deep Earth Drilling and Resource Development China University of GeosciencesWuhan430074China MLR Key Laboratory of Marine Mineral Resources Guangzhou Marine Geological SurveyGuangzhou510075China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao266071China

To further understand the characteristics of clay and sand production(hereafter collectively referred to as sand production)and to provide optimization designs of sand control schemes are critical for gas production from clayey silt natural gas hydrate reservoirs in the South China Sea.Thus,gas-water-sand production behavoirs and coupling reservoir subsidence characteristics before,during,and after hydrate dissociation of the clayey silt hydrate reservoirs with different clay contents(5%,10%,15%,20%,25%,and 30%)have been studied through a self-developed experimental system.The results show that with the increase of clay content,the total mass of sand production first increases and then decreases,and it reaches maximum when the clayey content is 20%.The sand production is the lowest before hydrate dissociation and increases significantly during hydrate dissociation,which mainly occurs in the high-speed gas and water production stage at the beginning of hydrate dissociation.After hydrate dissociation,the sand production decreases significantly.During the whole depressurization process,the clay and free sand particles generally move to the sand outlet due to the fluid driving force and overlying stress extrusion.However,for conditions of high clay contents,those particles fail to pass through the sand control screen and gradually accumulate and block the screen by forming a mud cake,which greatly reduce the permeability of the screen and limite sand production as well as gas and water production.Our research lays a foundation for sand production prediction and sand control scheme selection during gas recovery from clayey silty hydrate reservoirs that greatly need to consider a balance between sand control and gas productivity.

关键词： Natural gas hydrate Clayey silt reservoir Clay content Depressurization Sand production Sand control

Histone H3 lysine 27 trimethylation suppresses jasmonate biosynthesis and signaling to affect male fertility under high temperature in cotton

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Plant Communications 2023年第6期4卷 96-112页

作者： yanlong li Miao Chen Aamir Hamid Khan Yizan Ma Xin He Jing Yang Rui Zhang Huanhuan Ma Chunyang Zuo Yawei li Jie Kong Maojun Wang Longfu Zhu Xianlong Zhang ling Min National Key Laboratory of Crop Genetic Improvement&Hubei Hongshan Laboratory Huazhong Agricultural UniversityWuhan 430070HubeiChina Institute of Economic Crops Xinjiang Academy of Agricultural SciencesUrumqi 830091XinjiangChina

High-temperature(HT)stress causes male sterility in crops,thus decreasing yields.To explore the possible contribution of histone modifications to male fertility under HT conditions,we defined the histone methylation landscape for the marks histone H3 lysine 27 trimethylation(H3K27me3)and histone H3 lysine 4 trimethylation(H3K4me3)by chromatin immunoprecipitation sequencing(ChIP-seq)in two differing upland cotton(Gossypium hirsutum)varieties.We observed a global disruption in H3K4me3 and H3K27me3 modifications,especially H3K27me3,in cotton anthers subjected to HT.HT affected the bivalent H3K4me3–H3K27me3 modification more than either monovalent modification.We determined that removal of H3K27me3 at the promoters of jasmonate-related genes increased their expression,maintaining male fertility under HT in the HT-tolerant variety at the anther dehiscence stage.Modulating jasmonate homeostasis or signaling resulted in an anther indehiscence phenotype under HT.Chemical suppression of H3K27me3 deposition increased jasmonic acid contents and maintained male fertility under HT.In summary,our study provides new insights into the regulation of male fertility by histone modifications under HT and suggests a potential strategy for improving cotton HT tolerance.

关键词： high temperature H3K27me3 H3K4me3 cotton anther jasmonate

不同慢性病中老年女性骨折风险及低骨量切点预测分析

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中国组织工程研究 2024年第14期28卷 2140-2144页

作者：常凤李彦龙哈尔滨体育学院黑龙江省哈尔滨市150008

背景:中老年女性是骨质疏松的高发人群,慢性病增加骨质疏松罹患风险。低骨量是骨质疏松发病前的危险阶段,目前缺少常见慢性病人群的骨折风险差异及诊断指标切点值的相关报道。目的:通过对不同慢性病中老年女性骨折风险的分析,探讨肥胖... 详细信息

背景:中老年女性是骨质疏松的高发人群,慢性病增加骨质疏松罹患风险。低骨量是骨质疏松发病前的危险阶段,目前缺少常见慢性病人群的骨折风险差异及诊断指标切点值的相关报道。目的:通过对不同慢性病中老年女性骨折风险的分析,探讨肥胖、高血压、高血脂、糖尿病、动脉硬化与骨密度的相关性,找到可预测低骨量指标的切点值,为防治骨质疏松提供参考。方法:将45-70岁203名女性受试者分为正常组和慢性病组,采用超声骨密度测量仪进行跟骨骨密度测试,采用动脉硬化仪测试肱-踝脉搏波传导速度,采用全自动生化分析仪测试血糖、血脂,采用身体成分分析仪测试体质量指数、脂肪质量及肌肉质量。结果与结论:①61-70岁女性骨密度和骨折风险系数及51-60岁、61-70岁骨强度与<50岁比较,差异有显著性意义(P<0.05);②糖尿病组骨折风险明显高于其余各组,动脉硬化组则高于正常组和肥胖组(P<0.05);③骨密度与年龄、左侧血管弹性程度、右侧血管弹性程度、三酰甘油呈负相关,与体质量指数呈正相关(P<0.05);上述指标与骨密度受试者工作特征(ROC)曲线下面积介于0.5-0.7之间,低骨量对应切点分别为55.5岁(年龄)、756.0 cm/s(左侧血管弹性)、789.0 cm/s(右侧血管弹性)、1.115 mmol/L(三酰甘油)、22.35 kg/m^(2)(体质量指数);④结论:糖尿病和动脉硬化增加中老年女性骨折风险,测定体质量指数、血管弹性和三酰甘油对女性低骨量预测具有一定早期诊断价值。

关键词：中老年女性骨折风险低骨量切点预测

Cytochrome P450 mono-oxygenase CYP703A2 plays a central role in sporopollenin formation and ms5ms6 fertility in cotton

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Journal of Integrative Plant Biology 2022年第10期64卷 2009-2025页

作者： Huanhuan Ma Yuanlong Wu Ruiling Lv Huabin Chi Yunlong Zhao yanlong li Hongbo liu Yizan Ma Longfu Zhu Xiaoping Guo Jie Kong Jianyong Wu Chaozhu Xing Xianlong Zhang ling Min National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural UniversityWuhan 430070China College of Biology and Agricultural Resources Huanggang Normal UniversityHuanggang 438000China College of Plant Science and Technology Huazhong Agricultural UniversityWuhan 430070China Institute of Economic Crops Xinjiang Academy of Agricultural SciencesXinjiang 830091China State Key Laboratory of Cotton Biology Institute of Cotton Research of Chinese Academy of Agricultural SciencesAnyang 455000China

The double-recessive genic male-sterile(ms)line ms5 ms6 has been used to develop cotton(Gossypium hirsutum)hybrids for many years,but its molecular-genetic basis has remained unclear.Here,we identified the Ms5 and Ms6 loci through map-based cloning and confirmed their function in male sterility through CRISPR/Cas9 gene editing.Ms5 and Ms6 are highly expressed in stages 7–9 anthers and encode the cytochrome P450 mono-oxygenases CYP703A2-A and CYP703A2-D.The ms5 mutant carries a single-nucleotide C-to-T nonsense mutation leading to premature chain termination at amino acid 312(GhCYP703A2-A^(312aa)),and ms6 carries three nonsynonymous substitutions(D98E,E168K,and G198R)and a synonymous mutation(L11L).Enzyme assays showed that GhCYP703A2 proteins hydroxylate fatty acids,and the ms5(GhCYP703A2-A^(312aa))and ms6(GhCYP703A2-D^(D98E,E168K,G198R))mutant proteins have decreased enzyme activities.Biochemical and lipidomic analyses showed that in ms5 ms6 plants,C12–C18 free fatty acid and phospholipid levels are significantly elevated in stages 7–9 anthers,while stages 8–10 anthers lack sporopollenin fluorescence around the pollen,causing microspore degradation and male sterility.Overall,our characterization uncovered functions of GhCYP703A2 in sporopollenin formation and fertility,providing guidance for creating male-sterile lines to facilitate hybrid cotton production and therefore exploit heterosis for improvement of cotton.

关键词： cotton cytochrome P450 mono-oxygenase doublerecessive genic male sterility sporopollenin formation

放牧和刈割对内蒙古典型草原植物养分的不同影响

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Journal of Plant Ecology 2023年第1期16卷 25-36页

作者： Jiayue liu Lu li Lei Ji yanlong li Jiaojiao liu Frank Yonghong li Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau and Inner Mongolia Key Laboratory of Grassland Ecology School of Ecology and EnvironmentInner Mongolia UniversityHohhot 010021China Collaborative Innovation Center for Grassland Ecological Security Ministry of Education of ChinaHohhot 010021China National Agricultural Experimental Station for Soil Quality Institute of Grassland ResearchChinese Academy of Agricultural ScienceHohhot 010022China

放牧和刈割管理是天然草原的两种主要利用方式。放牧和刈割分别通过粪尿归还和养分移除的形式影响草原生态系统养分循环。植物养分对草原生态系统养分循环具有敏感的响应。然而,放牧和刈割管理在植物器官水平、种群和群落水平对植物养... 详细信息

放牧和刈割管理是天然草原的两种主要利用方式。放牧和刈割分别通过粪尿归还和养分移除的形式影响草原生态系统养分循环。植物养分对草原生态系统养分循环具有敏感的响应。然而,放牧和刈割管理在植物器官水平、种群和群落水平对植物养分具有怎样的影响,目前还缺乏准确的认知。我们在内蒙古半干旱草原地区通过野外控制实验探究持续放牧和轮牧以及低频率刈割和高频率刈割对草原生态系统的影响,并对不同处理下植物群落特征进行调查以及群落优势物种碳、氮和磷浓度进行测定。结果表明,(i)在持续放牧和轮牧下随放牧强度的增加,群落高度和地上现存量显著降低;每年一次刈割处理显著降低群落高度和地上现存量;(ii)在两种放牧制度下随放牧强度的增加,植物地上部分碳浓度显著降低,而氮、磷浓度则显著提高;不同刈割制度对植物地上部分碳、氮、磷浓度无显著影响;(iii)在两种放牧制度下随放牧强度的增加,植物群落碳、氮、磷库显著降低;不同刈割制度对植物群落碳、氮、磷库无显著影响;(iv)两种放牧下随放牧强度的增加,植物根系碳、氮、磷浓度无显著变化;两种刈割制度下植物根系碳、氮、磷浓度无显著变化,表明植物根系养分对外界干扰具有相对较高的稳定性和滞后性。本研究从多角度阐明了放牧和刈割管理对草原生态系统养分循环的影响。

关键词：放牧制度刈割制度植物地上养分植物根系养分典型草原