Results 21 to 30 of about 145 (85)
Shuitu Baochi Xuebao, 2022 为了解内蒙古河套灌区农田防护林内冻融期土壤水盐状况及运移规律, 在2020年10月至2021年4月实测土壤水分、盐分、温度及相关气象数据, 并进行相关分析。结果表明: 土体表层温度波动较大, 随土层深度加深土体温度变化逐渐平缓。冻结期气温下降速率低于消融期气温回升速率, 加之土壤温度变化的滞后性, 冻结期比消融期长10天左右。季节性冻融冻结作用导致表层土壤含水量升高、深层含水量降低, 消融解冻时期, 土壤含水量逐渐降低。两侧林带农田边缘(0.3 H、4 H)土壤表层含水量相比农田内部(1 H、2 H、3
郝可心 +4 more
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Exploration of hidden structure and prediction of gas anomaly area based on gas control projects [PDF]
The investigation of hidden structures and the prediction of gas abnormal area form the foundation of gas disaster prevention engineering. In accordance with the laws and regulations governing coal mining in our country, a gas pumping project must be ...
Hongqing CUI +3 more
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Dianci bileiqi, 2019 高海拔地区的风电场在冬季容易形成冻土层,冻土层的土壤电阻率变大,不利于风电机组遭受短路故障时的散流。基于风电机组接地网等电位模型研究季节性冻土因素下风机接地电阻季节系数的影响因素及其影响规律,以及垂直接地极、接地网水平引外对接地电阻季节系数的改善作用。研究结果表明:当接地网位于冻土层时,接地电阻季节系数受土壤电阻率反射系数的影响较大,当接地网位于非冻土层时,接地电阻季节系数几乎不受反射系数的影响;当冻土层厚度小于接地网埋深时,各土壤电阻率反射系数下的接地电阻季节系数基本不变并趋近于1 ...
姜龙杰 +5 more
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Dianci bileiqi, 2017 甘孜理塘县建有高海拔最高的变电站,该地区是典型的季节性冻土区域,为了研究该地区地网的安全性,对该地区季节性冻土的特征进行研究。首先采用不等间距四极法对该地区的土壤进行了测量,并采集了不同深度的土壤样本,根据土壤样本及测量结果对该地区的土壤结构及电阻率进行了反演,并将反演结果与三极法测量结果进行了对比验证,最后研究了冻土层对地表电位的影响。研究结果表明:在理塘这种高海拔季节性冻土地区,冻土的温度、深度及电阻率主要受大气温度的影响,冻结时温度从表层向下温度逐步降低,土壤电阻率逐渐下降 ...
罗琛 +6 more
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Progress in developments and applications of the HYDRUS model and associated coupling model packages [PDF]
HYDRUS model is widely used in agricultural irrigation and pollution transport because it can comprehensively consider the movement of water, heat, and pollutants in the soil-plant-atmosphere system.
Bei ZHANG +5 more
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Dianci bileiqi, 2020 为了研究温度因素对季节性冻土区域接地网故障测量的影响,测量分析了冻土温度变化过程水分和盐分迁移以及电阻率情况,并在冻土参数测量结果的基础上,采用接地网无损检测装置来分析温度变化对冻土区域接地网故障测量的影响。研究结果表明,冻融阶段温度梯度和孔隙水压梯度是水分迁移的主要驱动力,冻土冻结锋面以上和锋面下缘的土壤含盐量有上升趋势,冻土土壤冻结锋面附近电阻率急剧变化,这些由温度引起的冻土变化直接影响着接地网故障测量的准确度,即冻土深度低于水平接地网深度时,测量接地网故障准确率较高。
张晋宝 +5 more
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Dynamic characteristics and damage model of freezing thawing red sandstone under impact load [PDF]
To study the dynamic mechanical properties and damage evolution characteristics of freeze-thaw rocks under impact loads, 0, 15, 30, 45, and 60 freeze-thaw cycle tests and dynamic impact tests were conducted on red sandstone in cold regions.
Huiming ZENG +5 more
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Progress Analysis and Development Prospects of Soil Ecological and Environmental Effects of Interlayer Construction [PDF]
[Objective] This study systematically summarized and analyzed the current application status, technical characteristics, and environmental benefits of interlayer construction in soil improvement, nutrient cycling, ecological restoration, and crop ...
CHEN Jihong +7 more
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Review of techniques and case studies for saline-alkali land amelioration in the coastal regions of China [PDF]
Soil salinization is one of the major challenges in agricultural production and ecological development. With the rapid development of China’s coastal areas, land resources are becoming increasingly scarce, creating an urgent need for the improvement and ...
Hang LYU +5 more
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Shuitu Baochi Xuebao, 2017 为探索石河子灌区冻融季节积雪与地表联合覆盖条件下土壤水盐运移的变化规律，2015—-2016年通过田间小区试验，进行了秸秆、地膜、活性炭3种地表覆盖和裸地对照在整个季节性冻融期土壤水盐时空动态变化规律研究。结果表明：地表覆盖比裸地具有更好的保墒、降盐效果。冻结土壤完全融通后，秸秆、活性炭覆盖出现含水量增幅的最大土层范围分别是0—30，0—40 cm，反映出这2种覆盖经历冻融过程后更有利于土壤水分的保持和融雪水的高效利用；活性炭、秸秆、地膜覆盖和裸地在0—30 cm土层含盐量相比初始值的增幅分别为18 ...
唐文政 +3 more
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