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动车组前端排雪动态响应及雪阻形成机理

中南大学学报（自然科学版） 2024年第5期55卷 1900-1911页

作者：王中钢邓迎澳赵一鸣袁可申路民中南大学交通运输工程学院轨道交通安全教育部重点实验室湖南长沙410075 湖南工学院智能制造与机械工程学院湖南衡阳421002

为确定动车组前端雪体与排雪阻力间的作用关系,指导积雪加载下动车组高效排雪设计。运用耦合Drucker−Prager失效准则定义下弹塑性积雪本构和光滑粒子流体力学仿真方法,分析积雪冲击时排障面板动态响应及积雪运动状态规律,研究排雪阻力... 详细信息

为确定动车组前端雪体与排雪阻力间的作用关系,指导积雪加载下动车组高效排雪设计。运用耦合Drucker−Prager失效准则定义下弹塑性积雪本构和光滑粒子流体力学仿真方法,分析积雪冲击时排障面板动态响应及积雪运动状态规律,研究排雪阻力与积雪深度、雪质特性、运行边界间变化规律。基于质量守恒和达朗贝尔原理构建动车组排雪阻力映射模型,揭示动车组前端雪阻形成机理。研究结果表明:设计运行速度下承受排雪载荷的排障面板处于弹性响应阶段,不会发生塑性破坏;排雪深度为10~410 mm、积雪密度为160~480 kg/m^(3)、行驶速度为80~160 km/h时,排雪阻力与积雪厚度、密度均呈线性正相关关系,与排雪速度呈二次正相关关系;排雪阻力理论模型能够准确预测数值计算结果;相比摩擦阻力和切削阻力,动车组冲击过程中积雪运动状态改变是排雪阻力形成的主要原因。

关键词：动车组排障面板排雪阻力动态响应

黄土高原土壤调控原理与应用研究知识图谱——基于CiteSpace的文献可视化分析

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水土保持学报 2024年第1期38卷 396-408页

作者：崔彩贤沈霖远佳怡伊雅楠王忠港李玲玲西北农林科技大学人文社会发展学院陕西杨凌712100

[目的]黄土高原是中国一个伟大的地理单元,对国家粮食安全和生态安全具有重要的战略意义。通过长期的坡度治理、流域综合治理、植树造林等多种措施,黄土高原地区的生态环境已经得到显著改善,但仍然面临着局部地区植被恢复配置的合理性... 详细信息

[目的]黄土高原是中国一个伟大的地理单元,对国家粮食安全和生态安全具有重要的战略意义。通过长期的坡度治理、流域综合治理、植树造林等多种措施,黄土高原地区的生态环境已经得到显著改善,但仍然面临着局部地区植被恢复配置的合理性不足、全流域统筹不协调、平衡经济发展与生态保护等方面的挑战。在国家双碳目标的指引下,黄土高原生态系统及农业可持续发展的未来方向和目标应当是支持碳中和目标实现、建立环境适宜性的植被群落、推进生态系统统筹社会经济系统的发展实现发展方式绿色转型。[方法]通过文献计量学工具CiteSpace对1992—2023年发表的黄土高原土壤调控原理与应用研究相关文献进行可视化分析,重点针对该研究领域的核心研究力量、研究热点与研究趋势。[结果](1)从发文量的嬗变来看,整体呈上升趋势,在2001年后爆发式增长;(2)从发文机构来看,西北农林科技大学在该领域的发文量最高,为2157篇;(3)从作者的合作关系来看,邵明安和刘国彬是该领域的核心带头人,发文量分别为141,117篇,由他们构成的合作网络已经非常成熟;(4)从该领域的研究热点和发展趋势来看,主要研究热点集中在土壤水分、产量、旱地、土壤侵蚀、土壤养分和植被恢复等方面,未来微观主题趋势将集中在产量、坡位和施氮量上,而未来宏观趋势将探索生态—经济—社会系统耦合协调发展的新模式。[结论]基于可视化分析后的结果,对黄土高原土壤调控原理与应用研究领域提出了合作研究、研究热点和未来重点发展方向3个方面的展望。

关键词：黄土高原土壤调控原理与应用 CiteSpace 可视化产能协同提升

不同抗生素替代组合对断乳仔猪生长性能及腹泻率的影响

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福建畜牧兽医 2024年第1期46卷 9-12页

作者：黄晶朱靖雄邱阳王忠刚福建农业职业技术学院福州350119 广东广弘农牧发展有限公司广州510030

试验通过在断乳仔猪日粮中添加两种不同抗生素替代组合,分析两种抗生素替代组合对断乳仔猪生长性能和腹泻率的影响。试验选取90头平均体重接近的三元杂交(杜×长×大)健康断乳仔猪,采用单因子试验设计,将试验动物随机分成3个处理组,每组... 详细信息

试验通过在断乳仔猪日粮中添加两种不同抗生素替代组合,分析两种抗生素替代组合对断乳仔猪生长性能和腹泻率的影响。试验选取90头平均体重接近的三元杂交(杜×长×大)健康断乳仔猪,采用单因子试验设计,将试验动物随机分成3个处理组,每组3个重复,每个重复10头仔猪。日粮处理包括玉米-豆粕型基础日粮(对照组Ⅰ)、试验组Ⅱ、试验组Ⅲ,试验期为35d。结果表明:试验Ⅱ组和试验Ⅲ组平均末重、平均日增重和料重比均显著高于对照Ⅰ组(P0.05);在腹泻率方面,试验Ⅱ组和试验Ⅲ组均显著低于对照Ⅰ组,差异显著(P0.05)。由此可见,植物精油、中短链脂肪酸、有机酸组合和抗菌肽、中短链脂肪酸、有机酸两种组合均能改善仔猪的生长性能,降低断乳仔猪的腹泻率。

关键词：抗生素替代组合断乳仔猪生长性能腹泻率

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Madouzi-type (nodular) sedimentary copper deposit associated with the Emeishan basalt

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Science China Earth Sciences 2011年第12期54卷 1880-1891页

作者： wang FuDong ZHU XiaoQing wang zhonggang State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Ore minerals in the sedimentary-type Cu deposits in the Xuanwei Formation overlying the Emeishan basalt are dominated by copper sulfides and native copper. As the ores mostly exhibit concretionary structure, previous researchers named them the "Madouzi-type Copper Deposit". Here the authors carried out mineralogical and isotopic studies on copper nodules in this ore deposit. The mineralogical study shows that copper nodules are composed of copper sulfides that have been cemented by ferruginous amorphous minerals, clay, and carbonaceous fragments in the modes of metasomatism and sedimentation. The nodules are preliminarily present as aggregates of gelatinous material. The isotopic analysis shows that the δ 13CPDB values of an- thraxolite are within the range of-24.8‰--23.9‰, indicating that the anthraxolite is the product of sedimentary metamorphism of in-situ plants. The δ 34SV-CDT values of chalcocite are within the range of 7.6‰-13.1‰, close to those (about 11‰) of Permian seawater. The δ 34SV-CDT values of bornite and chalcopyrite are 21.6‰-22.2‰, similar to the sulfur isotopic composition (20‰) of marine sulfate, indicative of different sources of sulfur. The above characteristics indicate that the copper nodules were formed in such a process that Cu-bearing basalt underwent weathering-leaching and copper-bearing material was transported into waters (e.g., rivers, lakes, and swamps) and then adsorbed on clay and ferruginous amorphous mineral fragments. Then, the copper-bearing material was suspended and transported in the form of gelinite. In lake or swamp environment, it was co-deposited with sediments to form copper nodules. At later stages there occurred metasomatism and hydrothermal su- perimposition, followed by the replacement of chalcocite by bornite and the superimposition of chalcopyrite over bornite, finally resulting in the formation of the "Madouzi-type" nodular copper deposit.

关键词：峨眉山玄武岩铜矿床沉积型结节硫同位素组成同位素分析沼泽环境热液叠加

A rapid field crop data collection method for complexity cropping patterns using UAV and YOLOv3

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Frontiers of Earth Science 2024年第1期18卷 242-255页

作者： Huifang ZHANG Binyao wang zhonggang TANG Jiahui XUE Ruihang CHEN Hongcheng KAN Shumiao LU Lina FENG Ye HE Shuhua YI Institute of Fragile Eco-environment Nantong UniversityNantong 226019China School of Geographic Science Nantong UniversityNantong 226019China Nantong Key Laboratory of Spatial Information Technology R&D and Application School of Geographic ScienceNantong UniversityNantong 226019China

Crop type mapping using remote sensing is critical for global agricultural monitoring and food ***,the complexity of crop planting patternsand spatial heterogeneity pose significant challenges to field data collection,thereby limiting the accuracy of remotely sensed crop *** study proposed a new approach for rapidly collecting field crop data by integrating unmanned aerial vehicle(UAV)images with the YOLOv3(You Only Look Once version 3)*** impacts of UAV flight altitude and the number of training samples on the accuracy of crop identification models were investigated using peanut,soybean,and maize as *** results showed that the average Fl-score for crop type detection accuracy reached 0.91 when utilizing UAV images captured at an altitude of 20 *** addition,a positive correlation was observed between identification accuracy and the number of training *** model developed in this study can rapidly and automatically identify crop types from UAV images,which significantly improves the survey efficiency and provides an innovative solution for acquiring field crop data in large areas.

关键词： deep learning flight altitude crop survey peanut soybean maize

Metallogenic Model of Bauxite in Central Guizhou Province:an Example of Lindai Deposit

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Acta Geologica Sinica(English Edition) 2013年第6期87卷 1630-1642页

作者： LING Kunyue ZHU Xiaoqing wang zhonggang HAN Tao TANG Haoshu CHEN Wenyi Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academy of Sciences Institute of Geology Guizhou Bureau of Geology and Minerals

The bauxites in central Guizhou are hosted by the Lower Carboniferous Jiujialu *** characteristics of the Lindai bauxite deposit indicate that the underlying Shilengshui Formation dolomite is the precursor rock of mineral *** simulation experiments show that Si is most likely to migrate with groundwater,the migration rate of which is several magnitude higher than Al and Fe under nature conditions （pH=3-9）.The neutral and acid nonreducing condition is the most conducive to the Al rich and Si removal,while the acid reducing conditions is the most conducive to the Al rich and Fe *** the process of bauxite formation,coal beds overlying the Al-bearing rock series or other rock formation rich in organic materials can produce acid reducing groundwater,which are important for the bauxite ***,propose the metallogenic model of the bauxite in central Guizhou Province and put forward three new words which are ＂original bauxite material＂,＂bauxite material＂ and ＂original bauxite＂.

关键词： bauxite groundwater geochemistrial characteristics weathering simulation experiments Central Guizhou Province

Advances in geochemical research on nanometer materials

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Progress in Natural Science:Materials International 2006年第4期16卷 331-337页

作者： ZHU Xiaoqing and wang zhonggang Key Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Important advances have been made in the field of geochemistry since nanometer science and technology were introduced into the field of geoscience. The nanometer particulates have been discovered in naturally-occurring ore deposits, volcano-eruptive materials and geo-gases, and a more detailed exploration of the metallogenic mechanism of endogenic metallic ore deposits has been conducted. It is considered that some ore-forming metals may transport in the form of native particulates. Because they have very strong capabilities of adsorption, adsorption is always regarded as an important mechanism of metallogenesis under supergenic and low temperature conditions. Therefore, a new technology of ore exploration has also been developed. This paper attempts to review the new advances in geochemical research on nanometer materials, as well as its perspectivess.

关键词： nanometer geochemistry adsorption metallogenic theory prospecting method.

Preliminary Discussion on Comprehensive Utilization of Tailings

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矿物学报 2013年第S1期33卷 97-98页

作者： wang Fudong ZHU Xiaoqing wang zhonggang HAN Tao LI Zengsheng SUN Xiaohui LING Kunyao Southwest University of Science and Technology State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of Sciences

Tailings produced in a concentration plant are the discharge of solid wastes after grinding ore into size and selecting useful components in the specific economic and technological condition. According to statistics, for the mining of metal ore, non-metallic ore, coal, clay, etc, the production of tailings of the world is up to 100 million tons per year. The number of existing tailing piles is 12718 in China, of which the construction ones are 1526, accounting for 12% of the total, and the closed tailing piles are 1024, accounting for 8%. As of 2007, the national total tailings accumulation is 8.046 billion tons. The non-ferrous metal mining is one of the largest discharge of solid wastes industries because of its low comprehensive recovery rate. For example, the beneficiation and recovery rate of non-ferrous metal mine is from 50% to 60% in China, which is lower 10% to 15% than developed countries, and the associated non-ferrous metal recovery rate is 40%, which is lower 20% than developed countries. On the utilization of duns, Poland is 90% to 100%, United States, Australia, France, Canada, Belgium and other countries followed, while China is only about 20%. The utilization of fly ash is to 100% in Japan and Denmark, France is 65%, UK is 55%, and China is just 45%. Quantities of waste rock, waste slag, and waste water have occupied land, destructed vegetation, deteriorated the soil and water quality, and caused land subsidence, landslides, mud-flow and other geological disasters. Therefore, the comprehensive utilization of resources is the right choice of mining sustainable development, environment protection, resource conservation, economic and social development.

关键词： tailings comprehensive utilization non-ferrous metal mining

高速列车设备舱底板夹芯结构异物冲击压痕行为及抗性强化

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中南大学学报（自然科学版） 2022年第5期53卷 1976-1988页

作者：刘杰夫雷紫平朱玉雯王中钢中南大学交通运输工程学院湖南长沙410083 中南大学轨道交通安全教育部重点实验室湖南长沙410083

采用理想刚-塑性模型结合芯材压剪屈服准则表征蜂窝夹芯结构压痕深度解析模型;利用有限元仿真分析面芯匹配系数(面板拉伸强度与芯材压剪强度的比值)对塑性压痕行为的影响;进而以局部抗性提升为目标,开展夹芯结构面芯几何参数优化设计,... 详细信息

采用理想刚-塑性模型结合芯材压剪屈服准则表征蜂窝夹芯结构压痕深度解析模型;利用有限元仿真分析面芯匹配系数(面板拉伸强度与芯材压剪强度的比值)对塑性压痕行为的影响;进而以局部抗性提升为目标,开展夹芯结构面芯几何参数优化设计,形成抗性强化设计原则。研究结果表明:引入芯材压剪屈服应力状态的压痕深度解析模型具有较高的预测精度;当芯材强度较低时,压痕深度随芯材强度变化更为敏感,当芯材强度较高时,压痕深度随面板强度变化更为敏感;与原有设备舱底板相比,优化后蜂窝夹芯设备舱底板侵彻深度下降10.10%,比吸能提升6.47%;采用合理的面芯匹配可获得更高的压痕抗性和比吸能。

关键词：高速列车设备舱夹芯结构冲击压痕抗性强化

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