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北祁连山西段双龙铁矿地质特征及矿床成因探讨

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西北地质 2017年第1期50卷 50-62页

作者：孔维琼丁书宏樊新祥张照伟董国祥赵吉昌陈晔甘肃省地矿局第四地质矿产勘查院甘肃酒泉735000 西安地质矿产研究所国土资源部岩浆作用成矿与找矿重点实验室陕西西安710054

双龙铁矿位于北祁连西段卡瓦铁矿矿集区,是北祁连西段铁多金属成矿带内继镜铁山矿床之后新发现的又一重要沉积变质型铁矿之一。双龙铁矿矿床赋存于长城系桦树沟组浅海沉积相碎屑沉积岩,矿体多呈层状,分布和产状受控于含矿地层,矿体厚度... 详细信息

双龙铁矿位于北祁连西段卡瓦铁矿矿集区,是北祁连西段铁多金属成矿带内继镜铁山矿床之后新发现的又一重要沉积变质型铁矿之一。双龙铁矿矿床赋存于长城系桦树沟组浅海沉积相碎屑沉积岩,矿体多呈层状,分布和产状受控于含矿地层,矿体厚度与围岩厚度变化呈正比;矿石具细粒结构、条带状构造,品位低、变化大,具沉积变质型铁矿的特点。通过矿床成因探讨,初步认为双龙铁矿为与海底喷流作用有关的沉积变质型铁矿,并建立了矿床模型。

关键词：双龙铁矿床沉积变质型铁矿海底喷流沉积朱龙关裂谷北祁连西段

旋耕机不同时速及灌水回耕次数对土壤改良的影响研究

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广东水利水电 2019年第12期 72-75页

作者：陈家立曾啸王韶姚俊董国祥广东省水利水电第三工程局有限公司

为了探究旋耕机不同时速及灌水回耕次数对土壤改良效果的影响,以雷州市塘塞村垦造水田成形田块为研究对象,通过添加土壤改良剂设计提高土壤有机质含量1%,使用改进旋耕机对30 cm耕作层土壤进行回耕处理试验,试验对成型田块在自然状态下... 详细信息

为了探究旋耕机不同时速及灌水回耕次数对土壤改良效果的影响,以雷州市塘塞村垦造水田成形田块为研究对象,通过添加土壤改良剂设计提高土壤有机质含量1%,使用改进旋耕机对30 cm耕作层土壤进行回耕处理试验,试验对成型田块在自然状态下干湿回耕组(EG)和对照干地回耕组(CK)的时速和回耕次数进行了设计,检测两种处理方式对土壤有机质及pH值的影响。其中EG组中旋耕机采用2~7 km/h进行干湿地回耕后有机质含量提升均值范围为1.05%~1.11%,pH值提升均值范围为6.50~7.25,CK组有机质提升2.49%,pH值为6.06。EG组中灌水回耕处理能使混合料水分和粒度及料中各组分均匀分布,提高土壤及改良剂的混匀程度,有效地提高土壤耕地质量和蓄水保土能力,促进粮食高产稳产。

关键词：垦造水田灌水回耕改良

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风浪中船舶主机油耗预报方法

上海船舶运输科学研究所学报 2020年第2期43卷 1-4,62页

作者：李传庆董国祥许贺陈伟民上海船舶运输科学研究所航运技术与安全国家重点实验室上海200135

基于模型试验,采用1978年国际拖曳水池会议(International Towing Tank Conference,ITTC)推荐的实船功率、航速预报方法对船舶在静水中的主机功率和航速进行预报。采用ITTC推荐的阻力、推力一致法对船舶在风浪环境中的功率进行预报,其中... 详细信息

基于模型试验,采用1978年国际拖曳水池会议(International Towing Tank Conference,ITTC)推荐的实船功率、航速预报方法对船舶在静水中的主机功率和航速进行预报。采用ITTC推荐的阻力、推力一致法对船舶在风浪环境中的功率进行预报,其中,风阻采用经验公式计算,波浪增阻采用基于切片法的辐射能法和近似公式计算。在此基础上,结合主机的燃油特性,对船舶在风浪中的主机油耗进行预报。分析风速、波高和浪向对主机油耗的影响,结果表明:在艏斜浪范围内,浪向对油耗的影响不明显;随着波高的升高和风速的增大,相同转速下船舶的航速减小,单位里程的油耗增加。

关键词：油耗功率-航速失速风浪增阻切片法

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节能前置导管对波浪增阻和失速的影响

上海船舶运输科学研究所学报 2013年第1期36卷 24-30页

作者：蒋永旭董国祥闫磊何惠明马雪泉航运技术与安全国家重点实验室上海200135

以8万t巴拿马型级散货船为例,分别进行了光体和带前置导管的快速性节能试验和耐波性波模型试验。试验结果表明,肥大型的散货船安装前置导管可以有效提高船舶推进效率约2%,从而达到节能的目的。前置导管在波浪中有一定的减摇作用,减小船... 详细信息

以8万t巴拿马型级散货船为例,分别进行了光体和带前置导管的快速性节能试验和耐波性波模型试验。试验结果表明,肥大型的散货船安装前置导管可以有效提高船舶推进效率约2%,从而达到节能的目的。前置导管在波浪中有一定的减摇作用,减小船舶在波浪中的阻力增加,减小船舶对船舶的失速差值百分比影响较大,失速差值百分比在10%以上。因此,在波浪中安装节能的前置导管对船舶的失速系数有一定的影响。

关键词：前置导管推进效率阻力增加船舶失速

Ecological effect of the plantation of Sabina vulgaris in the Mu Us Sandy Land,China

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Journal of Arid Land 2024年第1期16卷 14-28页

作者： NAN Weige dong Zhibao ZHOU Zhengchao LI Qiang CHEN guoxiang School of Geography and Tourism Shaanxi Normal UniversityXi'an 710062China Shaanxi Key Laboratory of Ecological Restoration in Shaanbei Mining Area Yulin UniversityYulin 719000China College of Prataculture Gansu Agricultural UniversityLanzhou 730070China

Vegetation restoration through artificial plantation is an effective method to combat desertification,especially in arid and semi-arid *** study aimed to explore the ecological effect of the plantation of Sabina vulgaris on soil physical and chemical properties on the southeastern fringe of the Mu Us Sandy Land,*** collected soil samples from five depth layers(0-20,20-40,40-60,60-80,and 80-100 cm)in the *** plantation plots across four plantation ages(4,7,10,and 16 years)in November 2019,and assessed soil physical(soil bulk density,soil porosity,and soil particle size)and chemical(soil organic carbon(SOC),total nitrogen(TN),available nitrogen(AN),available phosphorus(AP),available potassium(AK),cation-exchange capacity(CEC),salinity,p H,and C/N ratio)*** results indicated that the soil predominantly consisted of sand particles(94.27%-99.67%),with the remainder being silt and *** plantation age increased,silt and very fine sand contents progressively *** 16 years of planting,there was a marked reduction in the mean soil particle *** initial soil fertility was low and declined from 4 to 10 years of planting before witnessing an *** positive correlations were observed for the clay,silt,and very fine sand(mean diameter of 0.000-0.100 mm)with SOC,AK,and p *** contrast,fine sand and medium sand(mean diameter of 0.100-0.500 mm)showed significant negative correlations with these *** findings ascertain that the plantation of *** requires 10 years to effectively act as a windbreak and contribute to sand fixation,and needs 16 years to improve soil physical and chemical ***,these improvements were found to be highly beneficial for vegetation restoration in arid and semi-arid *** research can offer valuable insights for the protection and restoration of the vegetation ecosystem in the sandy lands in China.

关键词： Sabina vulgaris plantation age soil physical and chemical properties soil particle size soil fertility vegetation restoration Mu Us Sandy Land

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垦造水田工程中犁底层构筑试验的研究

广东水利水电 2019年第1期 51-54页

作者：陈家立董国祥姚俊黄强戴家强广东省水利水电第三工程局有限公司广东东莞523710

在保证工艺质量的前提下,为探索垦造水田工程中犁底层构筑中最优施工工艺和节约施工成本,以雷州市垦造水田项目区的田块为研究对象,采用防渗池模拟水田试验,不等次数机械碾压处理后进行保水试验对比研究。试验结果表明:合格犁底层的稳... 详细信息

在保证工艺质量的前提下,为探索垦造水田工程中犁底层构筑中最优施工工艺和节约施工成本,以雷州市垦造水田项目区的田块为研究对象,采用防渗池模拟水田试验,不等次数机械碾压处理后进行保水试验对比研究。试验结果表明:合格犁底层的稳定下渗率均低于1. 911 mm/h;在喷水、淋水调整粘土土壤水分至适合碾压程度的前提下,使用超重型(整体工作质量20 t)单钢轮机械式振动压路机以第1或第2速(2. 2～4. 5 km/h)的速度经过往复2～3次碾压,保水试验效果符合田块干旱时1次性灌水后田面保持田面水72 h的建设标准,避免了不必要的施工投入,研究可为广东省垦造水田工程积累施工经验。

关键词：垦造水田犁底层防渗试验施工技术

Influence of salinity and moisture on the threshold shear velocity of saline sand in the Qarhan Desert, Qaidam Basin of China: A wind tunnel experiment

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Journal of Arid Land 2019年第5期11卷 674-684页

作者： LI Chao dong Zhibao YIN Shuyan CHEN guoxiang YANG Junhuai College of Geography and Tourism Shaanxi Normal University

Determination of the threshold shear velocity is essential for predicting sand transport,dust release and *** this study,a wind tunnel experiment was conducted to evaluate the influence of salinity and moisture on the threshold shear velocity of saline *** sand samples(mean particle size of 164.50–186.08μm and the total silt,clay and salt content of 0.80%–8.25%)were collected from three saline sand dunes(one barchan dune and two linear dunes)in the Qarhan Desert,Qaidam Basin of *** saline sand samples were placed in two experimental trays for wet and dry processing to simulate deliquescence and desiccation,*** moisture content ranging from 0.30% to 1.90% was generated by the steam method so that the saline sand can absorb water in a saturated water vapor *** motion of sand particles was determined by the observers with a solid *** laser sheet(0.80 cm thick),which was emitted by the solid laser,horizontally covered the sand surface and was bound to the *** show that the cohesion of saline sand results from a combination of salt and *** threshold shear velocity increases exponentially with the increase in crust thickness for the linear sand *** is a positive linear correlation between the original moisture content and relative threshold shear *** threshold shear velocity of dewatered sand is greater than that of wet sand with the same original moisture *** results will provide valuable information about the sand transport of highly saline soil in the desert.

关键词： threshold shear velocity saline sand barchan dune linear dune crust thickness moisture content Qaidam Basin

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螺旋桨四象限水动力性能数值计算

上海船舶运输科学研究所学报 2016年第1期39卷 1-7页

作者：张文璨董国祥陈伟民杜云龙任海奎上海船舶运输科学研究所航运技术与安全国家重点实验室上海200135

采用求解RANS方程的方法并运用计算流体力学(Computational Fluid Dynamics,CFD)软件Fluent,对荷兰MARIN船模水池B系列螺旋桨的敞水四象限水动力性能进行CFD数值模拟;同时,将数值模拟结果与B系列螺旋桨敞水四象限试验图谱进行比较。结... 详细信息

采用求解RANS方程的方法并运用计算流体力学(Computational Fluid Dynamics,CFD)软件Fluent,对荷兰MARIN船模水池B系列螺旋桨的敞水四象限水动力性能进行CFD数值模拟;同时,将数值模拟结果与B系列螺旋桨敞水四象限试验图谱进行比较。结果表明,计算误差较小,验证了计算策略的正确性,也为后续进行螺旋桨四象限水动力性能研究打下了基础。

关键词： B系列螺旋桨四象限水动力性能数值模拟

Experimental study on seismic response and progressive failure characteristics of bedding rock slopes

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第5期14卷 1394-1405页

作者： Mingdong Zang guoxiang Yang Jinyu dong Shengwen Qi Jianxian He Ning Liang School of Engineering and Technology China University of Geosciences(Beijing)Beijing100083China Institute of Geosafety China University of Geosciences(Beijing)Beijing100083China Research Institute of Geotechnical Engineering and Hydraulic Structure North China University of Water Resources and Electric PowerZhengzhou450011China Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing100029China University of Chinese Academy of Sciences Beijing100049China Department of Geotechnical Engineering School of Civil EngineeringSouthwest Jiaotong UniversityChengdu610031China

Bedding rock slopes are common geological features in nature that are prone to failure under strong earthquakes. Their failures induce catastrophic landslides and form barrier lakes, posing severe threats to people’s lives and property. Based on the similarity criteria, a bedding rock slope model with a length of3 m, a width of 0.8 m, and a height of 1.6 m was constructed to facilitate large-scale shaking table *** results showed that with the increase of vibration time, the natural frequency of the model slope decreased, but the damping ratio increased. Damage to the rock mass structure altered the dynamic characteristics of the slope;therefore, amplification of the acceleration was found to be nonlinear and uneven. Furthermore, the acceleration was amplified nonlinearly with the increase of slope elevation along the slope surface and the vertical section, and the maximum acceleration amplification factor(AAF) occurred at the slope crest. Before visible deformation, the AAF increased with increasing shaking intensity;however, it decreased with increasing shaking intensity after obvious deformation. The slope was likely to slide along the bedding planes at a shallow depth below the slope surface. The upper part of the slope mainly experienced a tensile-shear effect, whereas the lower part suffered a compressive-shear force. The progressive failure process of the model slope can be divided into four stages, and the dislocated rock mass can be summarized into three zones. The testing data provide a good explanation of the dynamic behavior of the rock slope when subjected to an earthquake and may serve as a helpful reference in implementing antiseismic measures for earthquake-induced landslides.

关键词： Bedding rock slope Large-scale shaking table test Seismic response Progressive failure characteristics