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Origin of the Domesticated Horticultural Species and Molecular Bases of Fruit Shape and Size Changes during the Domestication, Taking Tomato as an Example

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Horticultural Plant Journal 2017年第3期3卷 125-132页

作者： SUN Liang CHEN Jie XIAO Kai yang wencai Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops Department of Vegetable Science China Agricultural University

Domestication of crop plants is the foundation of modern agriculture, which brings forth desirable changes in cultivated species that distinguish them from their wild relatives. This resulted in the origin of crop species at known geographical locations coinciding with the transition of human societies from hunter-gather to agrarian civilizations. Fruit size and shape are very important traits for horticulture industry, as well as for studying the domestication of the horticultural species. In this review, we have summarized the origin of some widely-grown horticultural crops and also the molecular bases of the fruit size and shape changes of the horticultural crops during the domestication, taking tomato as an example.

关键词： horticultural crops domestication fruit size fruit shape tomato

Crustal Poisson's ratio anomalies in the eastern part of North China and their origins

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Geoscience Frontiers 2011年第3期2卷 313-321页

作者： wencai yang Chen Qu Changqing Yu Key Laboratory of Continental Dynamics Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

Seismic tomography can provide both fine P-wave and S-wave velocity structures of the crust and upper mantle. In addition, with proper computation, Poisson＇s ratio images from the seismic velocities can be determined. However, it is unknown whether Poisson＇s ratio images have any advantages when compared with the P-wave and S-wave velocity images. For the purposes of this study, high- resolution seismic tomography under the eastern part of North China region was used to determine detailed 3-D crustal P- and S-wave seismic velocities structure, as well as Poisson＇s ratio images. Results of Poisson＇s ratio imaging show high Poisson＇s ratio （high-PR） anomalies located in the Hengshan-North Taihang-Zhangjiakou （H-NT-Z） region, demonstrating that Poisson＇s ratio imaging can provide new geophysical constraints for regional tectonic evolution. The H-NT-Z region shows a prominent and continuous high-PR anomaly in the upper crust. Based on Poisson＇s ratio images at different depths, we find that this high-PR anomaly is extending down to the middle crust with thickness up to about 26 kin. According to rock physical property measurements and other geological data, this crustal Poisson＇s ratio anomaly can be explained by Mesozoic partial melting of the upper mantle and basaltic magma underplating related to the lithospheric thinning of the North China craton.

关键词： Seismic tomography North China Craton crust Poisson's ratio anomaly Magma underplating

Design and experiment of the soil-covering and soil-compacting device for seedling raising and sowing of trough type panax notoginseng

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International Journal of Agricultural and Biological Engineering 2023年第5期16卷 113-122页

作者： wencai yang Wang Pu Lulu Xu Ziyuan Tian Jing Zhao Yijie Zhang Zhenjie yang College of Mechanical and Electrical Engineering Yunnan Agricultural UniversityKunming 650201China Agricultural and rural Bureau Southwest Guizhou 562499China

In order to improve the seedling quality of Panax notoginseng,combined with the special agronomic requirements of Panax notoginseng,a sharp angle roller soil-covering and soil-compacting device integrating the functions of soil-covering and soil-compacting was *** on the theoretical analysis of seed ditch conditions,soil-covering process and soilcompacting process,the structure of soil-covering and soil-compacting device was *** theoretical analysis and calculation,the diameter and length of soil-covering and soil-compacting wheel were 20 cm and 10.7-14.1 cm,respectively,the sharp angle and height range were 45°-105°and 0.8-1.6 cm respectively,and the spring stiffness was 38.54 N/mm;Using the discrete element method to simulate the soil-covering and soil-compacting process,it was obtained that when the sharp angle range was 60°-90°,the sharp angle height range was 0.8-1.2 cm,and the soil-covering effect was better;Taking the forward speed,ballast pressure,sharp angle and sharp angle height of the planter as the test factors,and taking the soil-covering thickness,grain spacing and soil compactness as the indexes,the four factor and three-level Box-Behnken Design test was carried *** response surface test analysis method was used to establish the regression equation between the factors and indexes,and determine the best parameter combination:the forward speed was 6.5 m/min,the ballast pressure was 360.5 N,the sharp angle was 67°,and the sharp angle height was 1 cm,at this time,the soil-covering thickness was 0.64 cm,the grain spacing was 5.03 cm,and the soil compactness was 321.77 *** to the soil trough test,the design of soil-covering and soil-compacting device met the agronomic requirements of plant spacing,soil-compactness and soil-covering thickness during seedling sowing of Panax *** research results can provide a reference for the design of Panax notoginseng seedling planter integrating pressing hole(ditching),so

关键词： Panax notoginseng trough type seedling raising and sowing soil-covering and soil-compacting EDEM test

A review on developments in the electrical structure of craton lithosphere

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Science China Earth Sciences 2020年第11期63卷 1661-1677页

作者： Xiangyun HU Wule LIN wencai yang Bo yang Hubei Subsurface Multiscale Imaging Laboratory Institute of Geophysics and GeomaticsChina University of GeosciencesWuhan 430074China School of Earth Sciences Zhejiang UniversityHangzhou 310058China

Cratons have a long history of *** this paper,applications of the magnetotelluric method used in the study of craton lithosphere over the past 30 years were reviewed,examining case studies of cratons in North America,South America,Asia,Australia,and *** nuclei of the Archean cratons,for example the Kalahari Craton and Rae Craton,are usually characterized by thick and highly resistive lithospheric *** or after the formation of the cratons,tectonothermal events,such as collision,mantle plume,and asthenosphere upwelling led to the formation of high-conductivity zones in the craton lithosphere,which could be attributed to the increased hydrogen content(of nominally anhydrous minerals),higher iron content,and formation of graphite films or sulfides along the grain boundary of *** conductive zones are characterized by resistivity discontinuities in craton *** particular,the conductive zones include(1)large-scale lithospheric mantle conductors beneath the Slave Craton,Gawler Craton,and central part of North China Craton(Trans-North China Orogen);(2)near-vertical high-conductivity zone associated with the fossil subduction zone beneath the Dharwar Craton and Slave Craton;and(3)regional lateral electrical discontinuities,such as a conductive anomaly under the Bushveld Complex of the Kaapvaal *** eMoho refers to the electrical discontinuity in the crust-mantle *** existing research,this has been detected under the condition of extremely high lithospheric resistivity with only a slight decrease in the lower crust,and in the case of a very thin conductive lower crust or the lack *** the resistivity model,the unique"mushroom-like"lower crust-lithosphere mantle conductor and very thin lower crust layer of the North China Craton may represent lithosphere destruction and/or *** also find that some of the cratons are still not well ***,extensive three-dimensional inversion and joint interpr

关键词： Craton Lithospheric electrical structure Magnetotellurics

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西南丘陵山区青贮玉米收获机评价体系研究

饲料工业 2024年第20期45卷 9-13页

作者：郑嘉鑫胡池马龙杨文彩王占洪戴冲云付宏财云南农业大学机电工程学院云南昆明650201 云南高校高原特色现代农业装备研究中心云南昆明650201 陆良县农业机械技术试验推广站云南曲靖655600

文章旨在研究我国西南丘陵山区青贮玉米收获机评价方法。依据农机选型的理论基础和青贮玉米适口性相关研究结果,通过专家咨询和实地调研的方法,基于定性与定量结合、理论与实际结合、农机与农艺结合等原则,从多维度对青贮玉米收获机进... 详细信息

文章旨在研究我国西南丘陵山区青贮玉米收获机评价方法。依据农机选型的理论基础和青贮玉米适口性相关研究结果,通过专家咨询和实地调研的方法,基于定性与定量结合、理论与实际结合、农机与农艺结合等原则,从多维度对青贮玉米收获机进行评价,并采用层次分析法,构建了由能耗、作业效率、作业效果、收获后地表情况、机具安全性、收获饲料适口性组成的6个二级指标和16个三级指标,并确立各指标权重。根据建立的青贮玉米收获机选型评价体系,在云南省陆良县选用当地常用的森睿4QZ-2400(1)、迈赛德4QZ-2300(2)、坤禾农装4QZ-265(3)三台青贮玉米收获机进行试验验证。结果表明:三台青贮玉米收获机的综合得分分别为0.76、0.69、0.55。试验结果与当地农户使用情况相同,表明青贮玉米收获机评价体系构建的合理性,为我国丘陵山区青贮玉米全程机械化的发展和农机企业的研发提供了一定的方向。

关键词：青贮玉米丘陵山区适口性收获机评价体系

Geothermal measurements in the pilot-boreholes of the China Continental Scientific Drilling

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Chinese Science Bulletin 2001年第20期46卷 1745-1748页

作者： WANG Jiyang HU Shengbiao yang wencai CHEN Benhe CHEN Zhenyan LI Tiejun Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China Institute of Geology Ministry of Land and Resources of ChinaBeijing 100037China

The geothermal measurements in the pilot-boreholes of the China Continental Scientific Drilling (CCSD) indicate that the temperature gradients in the target area of the deep drilling range from 19 to 26℃/km, which is lower than that (25-30℃/km) for the global continental area and similar to that for the KTB (21-28℃/km). Thermal conductivity measurements for 44 core samples show that the ultra-high pressure (UHP) metamorphic rocks have 50% higher thermal conductivity (with a mean of 3.94±1.26 W/mK) than that for the average value of the upper crust. The measured heat flow values vary between 76 and 80 mW/m2, higher than that for the global continental area (65±1.6 mW/m2) and the continental China (61±15.5mW/m2) as well as the adjacent North Jiangsu Basin (68 mW/m2), butlower than that below 1000 m in the KTB (85 mW/m2). The elevated heat flow in the pilot-boreholes can be attributed to the lateral heat concentration due to higher rock thermal conductivity of the VHP belt than that of the adjacent

关键词： temperature gradient thermal conductivity heat flow CCSD North Jiangsu.

Deep decalcification of factory-provided freezing acidolysis solution to achieveα-high-strength gypsum

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Chinese Journal of Chemical Engineering 2024年第5期69卷 143-151页

作者： wencai Ye Yulu Li Yonggang Dong Lin yang Yun Yi Jianxin Cao School of Chemistry and Chemical Engineering Guizhou UniversityGuiyang 550025China Engineering Research Center of Efficient Utilization for Industrial Waste Guizhou UniversityGuiyang 550025China Key Laboratory of Guizhou Province for Green Chemical Industry and Clean Energy Technology Guizhou UniversityGuiyang 550025China

The freezing acidolysis solution of the nitric acid-phosphate fertilizer process has a high calcium content,which makes it difficult to produce fine phosphate and high water-soluble phosphate fertilizer ***,based on the potential crystallization principle of calcium sulfate in NH_(4)NO_(3)-H_(3)PO_(4)-H_(2)O,the deep decalcification(*** removal)technology to achieveα-high-strength gypsum originated from freezing acidolysis-solutions has been firstly proposed and ***,calcium can be removed from the factory-provided freezing acidolysis-solution by neutralizing it with ammonia,followed by the addition of ammonium sulfate *** a result,the formation of calcium sulfate in the reaction system undergoes the nucleation and growth of CaSO_(4)·2H_(2)O(DH),as well as its dissolution and crystallization into short columnarα-CaSO_(4)·0.5H_(2)O(α-HH).Remarkably,with the molar ratio of SO_(4)^(2-)/Ca^(2+)at 1.8,the degree of neutralization(NH_(3)/HNO_(3) molar ratio)at 1.7,the reaction temperature of 94℃,and the reaction time of 300 min,the decalcification rate can reach 86.89%,of which the high-strengthα-CaSO_(4)·0.5H_(2)O(α-HH)will be ***,the deep decalcification product meets the standards for the production of fine phosphates and highly water-soluble phosphate ***,the 2 h flexural strength ofα-HH is 5.3 MPa and the dry compressive strength is 36.8 MPa,which is up to the standard of commercialα-HH.

关键词： Nitrophosphate Ammonia neutralization Deep decalcification High-strengthα-hemihydrate gypsum Controlled crystallization at atmospheric pressure

Effect of Heat Treatment on Microstructure and Mechanical Behavior of Cu-Bearing 316L Stainless Steel Produced by Selective Laser Melting

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 169-180页

作者： Huan yang Ying Liu Jianbo Jin Kunmao Li Junjie yang Lingjian Meng Chunbo Li wencai Zhang Shengfeng Zhou Sino-German College of Intelligent Manufacturing Shenzhen Technology UniversityShenzhen518118China Institute of Advanced Wear and Corrosion Resistance and Functional Materials Jinan UniversityGuangzhou510632China Department of Orthopedics First Affiliated Hospital of Jinan UniversityGuangzhou510632China

Cu-bearing stainless steels(SSs)with high strength,excellent plasticity,and effective antimicrobial properties hold significant potential for applications in the marine *** this study,Cu-bearing SSs with copper ranging from 0 to 6.0 wt%were successfully prepared using selective laser melting(SLM)*** the Cu-bearing SSs with different copper contents,the effect of heat treatment on the microstructural and mechanical behaviors was studied *** observations revealed that the subgrain size of Cu-bearing SSs increased with heat treatment at 500℃ and 700℃ for 6 ***,the tensile strength and elongation increased after the heat treatment temperature due to the combined effect of dislocations,twins,andε-Cu precipitated ***,after heat treatment at 700℃,the SLM4.5Cu sample exhibited an abnormal rise in tensile strength and *** finding suggests that the diffusion strengthening caused byε-Cu precipitates exceeded the stacking fault ***,the tensile strength and elongation reached 693.32 MPa and 56.94%,*** work provides an efficient approach for preparing Cu-bearing SSs with exceptional strength and plasticity.

关键词： Selective laser melting Cu-bearing stainless steel(SS) Heat treatment Mechanical properties

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