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Soil microbial community diversity and distribution characteristics under three vegetation types in the Qilian Mountains, China

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Journal of Arid Land 2023年第3期15卷 359-376页

作者： TONG Shan CAO Guangchao zhang Zhuo zhang jinhu YAN Xin Key Laboratory of Tibetan Plateau Land Surface Processes and Ecological Conservation(Ministry of Education) Qinghai Normal UniversityXining 810008China Qinghai Province Key Laboratory of Physical Geography and Environmental Process College of Geographical ScienceQinghai Normal UniversityXining 810008China Academy of Plateau Science and Sustainability People's Government of Qinghai Province and Beijing Normal UniversityXining 810008China

Qilian Mountains in Northwest China is a significant ecological security barrier due to its distinctive geographic setting,which has significant biological resource and gene pool.In order to assess the soil quality and ecosystem health in this area,we identified the structural characteristics and functional groups of soil microbial communities.This study focused on Amidongsuo,a typical watershed of the Qilian Mountains,and researched the vertical distribution and dominant populations of soil microorganisms in different habitats,and the relationship between soil microorganisms and environmental factors.Soil microorganisms from three grassland plots,five shrubland plots,and five forest plots in Amidongsuo were studied using high-throughput sequencing.The Venn diagram showed that the types of bacteria were fewer than those of fungi in Amidongsuo.Soil bacteria Acidobacteriota,Proteobacteria,and Methylomirabilota as well as fungi Basidiomycota,Ascomycota,and Mortierellomycota played dominant roles in Amidongsuo,according to the LEfSe(linear discriminant analysis(LDA)effect size)and community structure analyses.According to the ANOSIM(analysis of similarities)result,for both bacteria and fungi,R values of grassland and shrubland were small(R^(2)=0.045 and R^(2)=0.256,respectively),indicating little difference between these two ecosystems.RDA(redundancy analysis)showed a closer relationship between soil nutrients and fungi,and a gradually decreasing correlation between soil nutrients and microorganisms with increasing soil depth.Bacteria were mainly affected by pH,nitrogen(N),and potassium(K),while fungi were mainly affected by K.Overall,fungi had more effect on soil quality than bacteria.Therefore,adjustment of soil K content might improve the soil environment of Amidongsuo in the Qilian Mountains.

关键词： fungi bacteria diversity soil nutrient Qilian Mountains

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Refinement ofα′Martensite by Oxygen in Selective Laser Melted Ti-6Al-4V

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Acta Metallurgica Sinica(English Letters) 2024年第5期37卷 777-792页

作者： Hasfi FNurly jinhu zhang Dechun Ren Yusheng Cai Haibin Ji Dongsheng Xu Zhicheng Dong Hao Wang Qingmiao Hu Jiafeng Lei Rui Yang School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials and Chemistry/Interdisciplinary Centre for Additive Manufacturing University of Shanghai for Science and TechnologyShanghai 200093China Centre for Adaptive System Engineering ShanghaiTech UniversityShanghai 201210China

Oxygen is crucial in influencing the microstructure evolution of selective laser melted(SLMed)Ti–6Al–4V,significantly impacting its applicability in various sectors.Therefore,this study investigates the influnce of oxygen on microstructure evolution,particularlyα′martensite transformation and refinement mechanisms.Four alloys,Ti–6Al–4V–xO(x=0.11,0.16,0.21,and 0.25 wt%),were fabricated by the SLM process.The martensite start temperature(M_(s))of Ti–6Al–4V,as evaluated by computation,is 656.8°C,and oxygen was found to increase the M_(s) by about 10°C per 0.1 wt%.The SLMed alloy samples exhibit[001]_(β)growth texture along the build direction.Crystallographic analysis of martensite morphology suggests internal twinning on{1011}planes as the lattice invariant strain,which becomes more predominant with increasing oxygen content.Refinement of α′martensite plates by oxygen is due to increased lattice distortion,reduced prior β grain size,and oxygen segregation toβgrain boundaries.Our findings contribute to improving the understanding of the effect of oxygen on the transformation mechanism ofα′martensite during SLM of Ti–6Al–4V.

关键词： Selective laser melting α′Martensite Martensite start temperature Oxygen Ti-6Al-4V

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Sedimentary characteristics and main controlling factors of the Middle-Upper Permian and Middle-Upper Triassic around Bogda Mountain of Xinjiang,NW China

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Petroleum Exploration and Development 2022年第4期49卷 770-784页

作者： YANG Youxing zhang Junfeng zhang jinhu GAO Yongjin ZHOU Xingui SUN Xiangcan WEN Lei MIAO Miaoqing Oil and Gas Survey Center of China Geological Survey Beijing 100083China

Based on field geological survey,interpretation of seismic data and analysis of drilling and logging data,the evolution of geological structures,stratigraphic sedimentary filling sequence and sedimentary system around the Bogda Mountain were analyzed according to the idea of"structure controlling basin,basin controlling facies and facies controlling assemblages".The tectonic evolution of the basin around the Bogda Mountain can be divided into nine stages.The Middle-Late Permian–Middle-Late Triassic was the development stage of intracontinental rift,foreland basin and inland depression basin when lake,fan delta and braided river delta sedimentary facies developed.Early intracontinental rifting,late Permian tectonic uplift,and middle-late Triassic tectonic subsidence controlled the shape,type,subsidence rate and sedimentary system evolution of the basin.The Bogda Mountain area was the subsidence center and deposition center of the deep water lake basin in the Middle Permian with mainly deep-water deposition and local gravity flow deposition.This area had tectonic inversion in the Late Permian,when the Bogda Mountain uplifted to form a low bulge and a series of fan delta sand bodies.In the Middle-Late Triassic,subsidence occurred in the Bogda low uplift,characterized by extensive development of braided river delta deposits.

关键词： Junggar Basin Bogda Mountain Fukang fault zone Permian Lucaogou Formation Triassic sedimentary filling sequence sedimentary system

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Oil exploration breakthrough in the Wensu salient, northwest Tarim Basin and its implications

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Petroleum Exploration and Development 2019年第1期46卷 16-26页

作者： zhang Junfeng GAO Yongjin YANG Youxing ZHOU Xingui zhang jinhu zhang Yuanyin Oil and Gas Survey Center of China Geological Survey

Both the XWD1 and XWD2 wells drilled in 2017 in the Wensu salient, northwest Tarim Basin have achieved high-yield industrial oil flow. Based on the comprehensive research on drilling, oil testing, geochemistry and logging data, in combination with the field surveys, 2 D seismic data processing and interpretation as well as sedimentation and accumulation history comparison, we carefully compared the source conditions, migration channels, reservoir-cap distribution and trapping types in the Wensu salient, and subsequently constructed a reservoir-forming pattern. Though the Wensu salient is lack of source rocks, some drainage systems were widely developed and efficiently connected to adjacent fertile depressions. Due to the moderate Miocene paleogeomorphic conditions in the Wensu salient, the delta and shore-shallow lacustrine beach bar sandy bodies were developed within the Jidike formation, and consequently form widely distributed structural-lithologic traps. The hydrocarbon generation, migration and accumulation mainly happened in the Neogene-Quaternary period, which suggests that the reservoir-forming pattern should be characterized as late-period and compound accumulation. It suggests that, although the border belts in the Tarim Basin might be short of source rocks and structural traps, they are potential to accumulate hydrocarbon in a large scale; the description of efficient hydrocarbon migration channels and structural-lithologic traps is crucial for any successful exploration.

关键词： structural-lithologic traps late hydrocarbon accumulation Neogene Jidike Formation weathering metamorphic crust Wensu salient Tarim Basin

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Stable isotope analysis of water sources for Tamarix laxa in the mega-dunes of the Badain Jaran Desert, China

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Journal of Arid Land 2018年第6期10卷 821-832页

作者： zhang jinhu WANG Nai'ang NIU Zhenmin SUN Jie DONG Chunyu zhang LyuLyu College of Earth and Environmental Sciences Lanzhou University State Key Laboratory Breeding Base of Gansu Desertification and Aeolian Sand Disaster Combating Gansu Desert Control Research Institute Department of Geography University of California

The complex interactions in desert ecosystems between functional types and environmental conditions could be reflected by plant water use patterns. However, the mechanisms underlying the water use patterns as well as the water sources of Tamarix laxa in the mega-dunes of the Badain Jaran Desert, China, remain unclear. This study investigated the water sources and water use patterns of T. laxa using the stable oxygen isotope method. The δ18O values of xylem water, soil water in different layers(0–200 cm), rainwater, snow water, lake water, atmospheric water vapor, condensate water, and groundwater were measured. The sources of water used by T. laxa were determined using the IsoSource model. The results indicate that T. laxa mainly relies on soil water. At the beginning of the growing season(in May), the species is primarily dependent on water from the middle soil layer(60–120 cm) and deep soil layer(120–200 cm). However, it mainly absorbs water from the shallow soil layer(0–60 cm) as the rainy season commences. In September, water use of T. laxa reverts to the deep soil layer(120–200 cm). The water use patterns of T. laxa are closely linked with heavy precipitation events and soil water content. These findings reveal the drought resistance mechanisms of T. laxa and are of significance for screening species for ecological restoration.

关键词： stable oxygen isotope water source water use pattern soil water stem water mega-dune Tamarix laxa

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Underwater acoustic metamaterials

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National Science Review 2023年第6期10卷 258-280页

作者： Erqian Dong Peizheng Cao jinhu zhang Sai zhang Nicholas X.Fang Yu zhang Key Laboratory of Underwater Acoustic Communication and Marine Information Technology of the Ministry of Education College of Ocean and Earth Sciences Xiamen University State Key Laboratory of Marine Environmental Science Xiamen University School of Physics and Electronic Engineering Jiangsu University Department of Mechanical Engineering Massachusetts Institute of Technology

Acoustic metamaterials have been widely investigated over the past few decades and have realized acoustic parameters that are not achievable using conventional materials.After demonstrating that locally resonant acoustic metamaterials are capable of acting as subwavelength unit cells,researchers have evaluated the possibility of breaking the classical limitations of the material mass density and bulk modulus.Combined with theoretical analysis,additive manufacturing and engineering applications,acoustic metamaterials have demonstrated extraordinary capabilities,including negative refraction,cloaking,beam formation and super-resolution imaging.Owing to the complexity of impedance boundaries and mode transitions,there are still challenges in freely manipulating acoustic propagation in an underwater environment.This review summarizes the developments in underwater acoustic metamaterials over the past 20 years,which include underwater acoustic invisibility cloaking,underwater beam formation,underwater metasurfaces and phase engineering,underwater topological acoustics and underwater acoustic metamaterial absorbers.With the evolution of underwater metamaterials and the timeline of scientific advances,underwater acoustic metamaterials have demonstrated exciting applications in underwater resource development,target recognition,imaging,noise reduction,navigation and communication.

关键词： underwater acoustic metamaterials invisibility cloaking beam formation topological acoustics metasurfaces absorbers

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高强TB9钛合金次生α相析出行为及力学性能

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航空材料学报 2024年第2期44卷 159-168页

作者：胡明邱建科雷晓飞张金虎董利民杨锐中国科学院金属研究所师昌绪先进材料创新中心沈阳110016

研究单/双重时效热处理对TB9合金次生α相形貌及力学性能的影响规律。借助XRD分析合金相组成,采用光学显微镜和扫描电子显微镜观察显微组织,着重分析微观组织形貌随时效温度变化的演变特征,测试室温拉伸性能和断裂韧度。研究结果表明:... 详细信息

研究单/双重时效热处理对TB9合金次生α相形貌及力学性能的影响规律。借助XRD分析合金相组成,采用光学显微镜和扫描电子显微镜观察显微组织,着重分析微观组织形貌随时效温度变化的演变特征,测试室温拉伸性能和断裂韧度。研究结果表明:单重时效时,晶粒内次生α相呈锯齿状和片层状析出,随着时效温度升高,α相尺寸增大,片层状α相含量增加;430℃时效时,合金强度较低,塑性较好,在470℃时效时合金强度最高;随时效温度的提高,强度先增大后维持在同一强度水平。双重时效时,晶粒内次生α相主要呈锯齿状析出,随时效温度升高,α相尺寸增大,抗拉强度先升高后降低,最高可达1542 MPa,且塑性变化较小。双重时效下合金的抗拉强度较单重时效大幅提高,这主要是由于晶界附近第二相析出强化和晶内锯齿结构α相的共同作用。

关键词： TB9合金次生α相显微组织力学性能

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6~10 m厚煤层超大采高液压支架及其工作面系统自适应智能耦合控制

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煤炭科学技术 2024年第5期52卷 276-288页

作者：韩会军王国法许永祥张金虎雷声李艳鹏煤炭科学研究总院开采研究分院北京100013 中煤科工开采研究院有限公司北京100013 天地科技股份有限公司北京100013

厚煤层储量及产量占我国原煤总储量及产量的一半,通过梳理厚煤层开采历史沿革,总结了我国厚煤层开采40年来的技术及装备研发实践,系统分析了以高端大采高液压支架及围岩智能耦合理论为代表的6~10 m大采高综采高效智能化综采技术及装备... 详细信息

厚煤层储量及产量占我国原煤总储量及产量的一半,通过梳理厚煤层开采历史沿革,总结了我国厚煤层开采40年来的技术及装备研发实践,系统分析了以高端大采高液压支架及围岩智能耦合理论为代表的6~10 m大采高综采高效智能化综采技术及装备研究进展,提出了大采高支护理论及围岩智能耦合控制的突破是厚煤层一次开采高度突破的首要因素,完善的感知体系建立是液压支架自适应支护的前提,数字技术的应用为大采高工作面高效推进及装备智能协同控制提供了新的技术途径;阐明了大采高综放液压支架与围岩耦合关系,剖析了采高增加对硬煤层冒放性的有利影响,提出了基于煤矸识别、放煤机构控制的“纯煤段记忆放煤+煤岩分界模糊段人工反馈式干预放煤”的智能放煤控制策略;分析了大采高开采“采–运”协同智能耦合控制关键技术,构建了基于采煤机牵引速度与刮板输送机链速间联动调节的工作面装备间多机异构耦合自适应协同控制模型;研发了厚煤层开采中10 m超大采高液压支架,分析了厚煤层开采不断突破开采高度极限的新认识,从开采装备、控制系统等方面提出厚煤层一次开采高度的突破的研发方向。

关键词：厚煤层开采高端开采装备支架–围岩耦合大采高综采大采高综放

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Distribution Features of the Nanhua-Sinian Rifts and their Significance to Hydrocarbon Accumulation in the Tarim Basin

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Acta Geologica Sinica(English Edition) 2020年第2期94卷 501-515页

作者： BAI Zhongkai CHENG Minghua CHEN Cheng HUO Junzhou zhang Junfeng ZHOU Xingui GAO Yongjin ZHAO Bo QIU Haijun HAN Miao YANG Youxing SUN Zhichao MIAO Miaoqing zhang jinhu LI Qingyao Oil and Gas Survey CGSBeijing 100083China Korla Branch Research Institute of BGP KorlaXinjiang 841000China Institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081China The 6th Gas Production Plant of Petrochina Changqing Oilfield Company Xi'an 710000China China Geological Survey Beijing 100029China

On the basis of reprocessing 34 new two-dimensional spliced long sections(20,191 km) in the Tarim Basin, the deep structure features of the Tarim Basin were analyzed through interpreting 30,451 km of two-dimensional seismic data and compiling basic maps. Seismic interpretation and geological analysis conclude that the Nanhua-Sinian strata are a set of rift-depression depositional systems according to their tectonic and depositional features. The rift valley formed in the Nanhua Period, and the transformation became weaker during the late Sinian Period, which eventually turned into depression. From bottom to top, the deposited strata include mafic igneous, tillite, mudstone, and dolomite. Three major depocenters developed inside this basin during the rift stage and are distributed in the eastern Tarim Basin, the Awati area, and the southwestern Tarim Basin. Among them, the rift in the eastern Tarim Basin strikes in the near east-west direction on the plane and coincides with the aeromagnetic anomaly belt. This represents a strong magnetic zone formed by upwelling basic volcanic rock along high, steep normal faults of the Nanhua Period. Controlled by the tectonic background, two types of sedimentary systems were developed in the rift stage and depression stage, showing two types of sequence features in the Sinian depositional stage. The Nanhua System appears as a wedge-shaped formation, with its bottom in unconformable contact with the base. The rifting event has a strong influence on the current tectonic units in the Tarim Basin, and affects the distribution of source rock in the Yuertus Formation and reservoir beds in the Xiaoerbulake Formation in Lower Cambrian, as well as the gypseous cap rock in Middle Cambrian. The distribution features of the rifts have important and realistic significance for determining the direction of oil and gas exploration in the deep strata of the Tarim Basin. Comprehensive analysis suggests that the Tazhong region is the most favorable zone, and the Kalpin-Bachu region is the optimal

关键词： rift Nanhua Period Sinian Period Tarim Basin

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超大采高综采工作面支护技术及装备研究现状

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煤矿安全 2024年第5期55卷 213-221页

作者：韩会军王国法李明忠张金虎李艳鹏煤炭科学研究总院北京100013 中国煤炭科工集团有限公司北京100013 天地科技股份有限公司北京100013

超大采高一次采全厚开采具有开采效率高、资源回收率高等特点。为探求超大采高综采技术进一步突破,分析其工作面围岩稳定性控制可行性,在调研超大采高综采发展历程的基础上,总结了超大采高综采工作面围矿压显现及煤壁片帮规律,分析了现... 详细信息

超大采高一次采全厚开采具有开采效率高、资源回收率高等特点。为探求超大采高综采技术进一步突破,分析其工作面围岩稳定性控制可行性,在调研超大采高综采发展历程的基础上,总结了超大采高综采工作面围矿压显现及煤壁片帮规律,分析了现有超大采高液压支架整体技术特征及其适用性能,并介绍了10 m超大采高工作面液压支架基本情况。通过分析发现:工作面矿压显现强度与采高基本呈现正相关关系,采高越大,工作面支护阻力越大,且煤壁片帮是困扰超大采高开采高效推进的主要因素之一,通过提高工作面液压支架的初撑能力能有效减小煤壁应力;液压支架随工作面采高增加,选型工作阻力增大,支架中心距加宽,大梯度过渡方式在提供可靠支护的同时,能有效提升端头区资源回收率;为适应大体量开采装备运输,超大采高工作面煤巷断面增加,超前支架工作阻力增大;工作面配套液压支架通过设计手段、整体结构、制造工艺等方面优化升级以提升可靠性及适应性;相对较低采高工作面支护,超大采高开采更注重支护过程中的安全技术需求,需要完善架前煤矸防护、架间防尘降尘、安全的后期维检等安全措施;工作面围岩稳定性控制及其配套装备是超大采高综采技术发展及推广的重点,从支护参数选择、支护结构设计到液压支架制造、后期维检的超大采高液压支架全寿命开发是支撑超大采高开采高效推进的基础。

关键词：超大采高高端液压支架围岩稳定性控制工作面支护综采支护技术及装备

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