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地球内部可能利用的天然氢气

科技导报 2024年第15期42卷 7-14页

作者：杨文采浙江大学地球科学学院杭州310027

在21世纪,氢能源的应用和氢能产业的发展受到社会的广泛关注。从地球形成历史和地球物理数据来看,地球内部的地核就是一个氢能库。大陆科学钻探的数据表明,大地震产生环绕全球的地震波,使地壳和地幔中的裂隙带活动,地球内部的气体得以... 详细信息

在21世纪,氢能源的应用和氢能产业的发展受到社会的广泛关注。从地球形成历史和地球物理数据来看,地球内部的地核就是一个氢能库。大陆科学钻探的数据表明,大地震产生环绕全球的地震波,使地壳和地幔中的裂隙带活动,地球内部的气体得以释放。地震后地球在放氢气、氦气和甲烷等气体,它们会通过地幔裂隙带上涌到上地壳。如果上地壳有渗透率很低的岩层把上涌气体覆盖起来,就可能成为深层结晶岩中的氢类能源储存库。在中国,青藏高原东部可能有这种深层氢类能源储存库,值得进一步研究。

关键词：氢能源地核氢能库放气地壳储存

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东非大裂谷的地壳和上地幔密度结构

地质论评 2024年第1期70卷 1-8页

作者：钱知之杨文采浙江大学杭州310058

利用卫星重力场数据和小波多尺度分析方法对东非大裂谷进行三维密度结构成像,取得了东非大裂谷地壳和上地幔多个深度等效层上的密度扰动图像,为东非大裂谷岩石圈结构和动力学的研究提供了重要佐证。结果表明,东非大裂谷中段的西支裂谷... 详细信息

利用卫星重力场数据和小波多尺度分析方法对东非大裂谷进行三维密度结构成像,取得了东非大裂谷地壳和上地幔多个深度等效层上的密度扰动图像,为东非大裂谷岩石圈结构和动力学的研究提供了重要佐证。结果表明,东非大裂谷中段的西支裂谷与东支裂谷的幔源熔体同源,但是西支裂谷发育较不充分、形成较晚。东非大裂谷的动力学模式为熔流体上涌的树形分叉模式,其要点包括:(1)低密度流体在软流圈大面积上涌;(2)流体在岩石圈继续上涌,部分转化为基性岩浆岩,平面面积缩小;(3)进入地壳后上涌熔流体分叉成多支,平面总面积进一步缩小;(4)熔流体上涌到上地壳后仅在裂谷带活动,反映为火山链和玄武岩带。

关键词：东非大裂谷卫星重力场小波多尺度分析三维密度结构成像熔流体运动

玉米秸秆及其生物炭复配基质对玉米根系构型的影响

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华南农业大学学报 2024年第2期45卷 207-217页

作者：张立芸黎力张海东杨文彩云南农业大学机电工程学院云南昆明650201

【目的】研究玉米Zea mays L.秸秆及其生物炭对设施栽培中基质改良的价值,探明玉米根系构型及其对不同复配基质的响应。【方法】采用盆栽试验,测定并分析了不同配比基质的理化性质和玉米地上部、根系生物量,采用WinRHIZO(Pro.2020a)根... 详细信息

【目的】研究玉米Zea mays L.秸秆及其生物炭对设施栽培中基质改良的价值,探明玉米根系构型及其对不同复配基质的响应。【方法】采用盆栽试验,测定并分析了不同配比基质的理化性质和玉米地上部、根系生物量,采用WinRHIZO(Pro.2020a)根系分析系统分析计算玉米根系的形态以及分形、拓扑结构特征参数,采用SPSS软件分析地上部/根系生物量、根系形态特征与构型特征参数的相关性。【结果】添加秸秆及其生物炭的各处理中,T3处理(蛭石、珍珠岩、玉米秸秆和玉米秸秆生物炭的添加量分别为22.4、22.4、22.4和44.8 dm^(3))的理化性质相较CK最为优化,总孔隙度和持水孔隙度分别达到81.02%和55.38%,可利用的速效氮、磷、钾含量均处在最优水平。T3处理根系的生物量和根长、根表面积、根体积3个主要形态特征参数均与其他处理差异显著,分别高于CK处理112.82%、79.89%、101.21%和102.53%。随着秸秆及其生物炭添加比例的增加,各处理根系分形维数逐渐增大,从CK的1.425增大至T3的1.514;拓扑指数逐渐减小,从CK的0.699减小至T3的0.627,T3处理的拓扑指数更接近0.5。玉米根系生物量和主要形态特征参数与分形维数、分形丰度呈极显著正相关,与拓扑指数呈极显著负相关。【结论】添加秸秆及其生物炭可改善基质理化性质,为根系提供优质生长环境;环境对根系构型的可塑性较高,可以使玉米根系构型向更利于养分和水分利用的方向改变;根系构型性状可在一定程度上表征根系形态特征,也可作为指标来验证复合基质的栽培效果。

关键词：玉米玉米秸秆生物炭根系构型分形维数拓扑指数

Multi-scale inversion of density structure from gravity anomalies in Tarim Basin

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Science China Earth Sciences 2011年第3期54卷 399-409页

作者： HOU ZunZe yang wencai Chinese People's Armed Police Force Academy Langfang 065000 China Institute of Geology Chinese Academy of Geology Beijing 100037 China

Based on the power spectra of gravity anomalies in Tarim Basin, the anomalies can be decomposed to the following three components: a sub-anomaly formed mainly by the basin crystallized basement, a sub-anomaly formed mainly by deep sedimentary layers, and that by shallow sedimentary layers. A special wavelet transform analysis scheme and a density inversion method are designed and applied to the decomposition and inversion of gravity sub-anomalies, which are correlated with regional geology and drilling data. The results indicate that the deep and the shallow sub-anomalies show some relations with ancient fluid active zones. The negative density disturbances inversed from the shallow sub-anomaly are mainly caused by Mesozoic fluid active zones, whereas the negative density disturbances form the deep sub-anomalies are mainly correlated with Paleozoic fluid active zones. As the ancient fluid movement was good for formation of oil/gas fields, the multi-scale inversion methods for locating the ancient fluid movement zones seem to be helpful and valuable to oil/gas exploration.

关键词： gravity anomalies wavelet transform multi-scale analysis density inversion ancient fluid active zones Tarim Basin

Discovering Crustal Deformation Bands by Processing Regional Gravity Field

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Acta Geologica Sinica(English Edition) 2016年第1期90卷 66-74页

作者： yang wencai SUN Yanyun Lab of Continental Tectonics and Dynamics Chinese Academy of Geological Sciences.26 Baiwanzhuang RoadBeijing 10037China China Areo Geophysical Survey&Remote Sensing Center for Land and Resources 31 college RoadBeijing 100083China

Objectives： This article presents a new computational procedure to discover scratches buried in the earth＇s crust. We also validate this new interdisciplinary analysis method with regional gravity data located in a well-known Dabie orogenic zone for test. Methods： Based on the scratch analysis method evolved with mathematical morphology of surfaces, we present a procedure that extracts information of the crustal scratches from regional gravity data. Because the crustal scratches are positively and highly correlated to crustal deformation bands, it can be used for delineation of the crustal deformation belts. The scratches can be quantitatively characterized by calculation of the ridge coefficient function, whose high value traces delineate the deformation bands hidden in the regional gravity field. In addition, because the degree of crustal deformation is an important indicator of tectonic unit divisions, so the crust can be further divided according to the degree of crustal deformation into some tectonic units by using the ridge coefficient data, providing an objective base map for earth scientists to build tectonic models with quantitative evidence. Results： After the ridge coefficients are calculated, we can further enhance the boundary of high ridge-coefficient blocks, resulting in the so-called ridge-edge coefficient function. The high-value ridge-edge coefficients are well correlated with the edge faults of tectonic units underlay, providing accurate positioning of the base map for compilation of regional tectonic maps. In order to validate this new interdisciplinary analysis method, we select the Dabie orogenic zone as a pilot area for test, where rock outcrops are well exposed on the surface and detailed geological and geophysical surveys have been carried out. Tests show that the deformation bands and the tectonic units, which are conformed by tectonic scientists based on surface observations, are clearly displayed on the ridge and ridge-edge coefficient

关键词： tectonics earth's crust deformation band regional gravity field information extraction scratch analysis computer-generated image

Expanding the Wilson Cycle Based on Worldwide Comparison of Continental Structures Revealed by Lithospheric Geophysical Investigations

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Acta Geologica Sinica(English Edition) 2015年第2期89卷 327-331页

作者： yang wencai State key Lab of Continental Tectonics and Dynamics Institute of GeologyCAGS

Worldwide comparison of lithospheric investigation results achieved from projects of COCORP, BIRPS, DEKORP, LITHOPROBE, ICDP, ECORS and SINOPROBE enables us to expand the classical Wilson cycle, which mainly describes evolution of ocean plates, into a complete and detailed cycle that describes generation, development and evolution of both ocean and continent plates. The expanded Wilson cycle presented in this paper introduces the evolution sequences of continental lithospheric processes by adding into the classical Wilson cycle with ocean-continent transition, continental collision and accretion, as well as continental rifting and splitting in details. These mentioned continental lithospheric processes have been presented by the author in a series of recent review papers in detail, and their summary and further deduction is presented in this paper.

关键词： plate tectonics Wilson cycle worldwide comparison lithospheric investigation tectonicprocess ocean-continent transition continental accretion

Seismic response to natural gas anomalies in crystalline rocks

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Science China Earth Sciences 2008年第12期51卷 1726-1736页

作者： yang wencai JIN ZhenMin YU ChangQing Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Facuty of Earth Sciences China University of GeosciencesWuhan 430074China

According to the geological and seismic reflection data of the Chinese Continental Scientific Drilling (CCSD) main-hole (MH), and the anomalies of CH4, CO2, and He are correlated to the three-component seismic reflectors, especially in horizontal component profiles. However, the seismic response is dif-ficult to be explained as the porosity of crystalline rocks is only about 1% in well section where the gas anomalies occur. Seismic velocity measurement of the MH cores indicated that compared with wa-ter-saturated rock samples, seismic velocity (especially the S-wave) could be distinctly decreased by gas contained in tiny cracks despite of the low porosity, and then notable seismic response could be induced in gas-filled crystalline rocks. It could be predicated that if the porosity of certain rocks in the middle crust rose due to water-rock interaction and had natural gas filled, then there would be more probability for natural gas in top of the mid-crust to fill in the crystalline rocks with increased porosity. In such case, based on the decrease of Swave velocity in crystalline rocks, seismic method could be applied in the future to explore natural gas reservoirs in the middle crust.

关键词： scientific drilling crystalline basement gas anomalies in crust seismic reflection petrophysics

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蔬菜穴盘育苗播种机清种装置的设计与试验

华南农业大学学报 2024年第1期45卷 116-126页

作者：杨文彩田梓园潘吴建赵静张海东李贵荣云南农业大学机电工程学院云南昆明650201 宁波财经学院浙江宁波315175

【目的】针对蔬菜穴盘育苗播种机现有清种装置清种效果不好,导致的充种合格率低、重播率高问题,设计集机械式、气吹式、电控式为一体的清种装置。【方法】结合运动学及动力学理论对三级清种装置的结构进行设计;采用Ansys软件中Fluent模... 详细信息

【目的】针对蔬菜穴盘育苗播种机现有清种装置清种效果不好,导致的充种合格率低、重播率高问题,设计集机械式、气吹式、电控式为一体的清种装置。【方法】结合运动学及动力学理论对三级清种装置的结构进行设计;采用Ansys软件中Fluent模块对气吹式清种装置的不同进气口和出气口结构中的气流稳定性进行分析;在理论分析和仿真分析的基础上选取排种器转速、排种器负压、清种装置正压、种子直径为试验因素,结合农艺要求选取单粒充种合格率、重播率为试验指标开展四因素三水平二次回归正交试验。根据试验数据得出最佳参数组合。【结果】由仿真分析得出,中间端进气圆弧式喷嘴气吹式清种结构清种效果最好。由台架试验得到排种最佳参数组合,即在排种器转速为0.17 r/s、种子直径为1.5 mm、排种器负压为0.6 kPa、气吹式清种装置正压为0.3 kPa时,平均单粒充种合格率为95.31%,平均重播率为0.2%。【结论】本文设计的清种装置满足了蔬菜播种农艺要求,可以有效提升充种合格率、降低重播率,为生产实际提供理论指导。

关键词：蔬菜穴盘育苗播种机清种装置二次回归正交试验

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Breeding for Resistance to Tomato Bacterial Diseases in China:Challenges and Prospects

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Horticultural Plant Journal 2018年第5期4卷 193-207页

作者： WANG Yuqing ZHANG Yaxian GAO Zhipeng yang wencai Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops Department of Vegetable Science College of Horticulture China Agricultural University

Four bacterial diseases including bacterial canker caused by Clavibacter michiganensis subsp. michiganensis, bacterial speck caused by Pseudomonas syringae pv. tomato, bacterial spot caused by at least four Xanthomonas species, and bacterial wilt caused by Ralstonia solanacearum are among the most devastating diseases in tomato(Solanum lycopersicum) production in China. However, almost no commercial cultivars currently growing in the country are resistant to these four bacterial diseases because little effort has been devoted to breeding for resistance. In addition,the existence of great natural variation in each pathogen and the quantitative inheritance of resistance add to the difficulties of developing cultivars with resistance to these diseases. In the past 20 years, molecular markers tightly linked to genes conferring resistance to these four bacterial diseases have been identified or gene-based markers have been developed, which may circumvent some of the problems associated with phenotypic selection for resistance to multiple bacterial pathogens and races. Here we present a review on current status of studies on these diseases and discuss the promise of new technologies in breeding for resistance to these bacterial diseases in China.

关键词： tomato bacterial disease new breeding technology