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Application of Ground Phosphate Rock to Dimmish the Effects of Simulated Acid Rain on Soil Properties

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Pedosphere 1992年第2期2卷 147-152页

作者： DONG yuan-VAN and li xue-yuan Huazhong Agricultural University. Wuhan 430070 ( China)

The effects of simulated acid rain retained in soil on the properties of acid soil and its diminishing by application of ground phosphate rock were investigated by using the sorption method. Results show as follows: (1) For yellow brown soil, the effect of simulated acid rain on the properties of soil with a pH value of 5.9 was relatively small, except a great quantity of acid rain deposited on it. (2) For red soil, the effect of simulated acid rain on the properties of soil was significant. With the increase of the amount of acid deposition, the pH value of soil was declined, but the contents of exchangeable H+, Al3+ and Mn2+ and the amount of SO42- retention were increased. (3) Many properties of acid soils could be improved by applying ground phosphate rock. For example, pH value of soils and the amounts of available P and exchangeable Ca2+ and Mg2+ were increased, and the amounts of exchangeable H+ and Al3+ and SO42- retained was reduced. The application of ground posphate rock could effctively dimmish the pollution of acid rain to soil.

关键词： phosphate rock simulated acid rain soil properties

Ionic liquid-based Microwave-assisted liquid-liquid Microextraction and High Performance liquid Chromatography Determination of Sulfonamides from Animal Oils

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Chemical Research in Chinese Universities 2013年第4期29卷 647-652页

作者： FENG Xu-dong liANG Fang-hui SU Rui WU li-jie li xue-yuan WANG Xing-hua ZHANG Han-qi YU Ai-min College of Chemistry Jilin University Changehun 130012 P. R. China Department of Pharmacy Changchun Medical College Changchun 130117 P. R. China

The authors performed ionic liquid-based microwave-assisted liquid-liquid microextraction（IL-based MALLME） coupled with high performance liquid chromatographic separation for the determination of 6 sulfonamides （SAs） from animal oils. The target analytes were extracted from animal oil samples with sodium hydroxide solution containing 1-butyl-3-methylimidazolium tetrafluoroborateand as the extraction solvent under microwave irradiation. The experimental parameters of the IL-based MALLME, including types of ILs, volume of IL, amount of ion-pairing agent（NHaPF6）, pH value of sample solution, and extraction temperature and time were evaluated. The limits of detection and quantification obtained were in a range of 0.4--0.5μg/kg and a range of 1.2--1.8μg/kg, respectively. The accuracy of the method was evaluated by analyzing five spiked animal oil samples at two fortified levels（5 and 50μg/kg）, and the recoveries of SAs varied from 81.4% to 114.5% with relative standard deviations ranging from 0.8% to 9.0%.

关键词： Ionic liquid-based microwave-assisted liquid-liquid microextraction(IL-based MALLME) High perfor-mance liquid chromatography(HPLC) Sulfonamide Animal oil

Goethite　Morphologies　of　Some　Soils　in　South　of　Central　China

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Pedosphere 1996年第3期 193-200页

作者： liU FAN XU FENG-liN li xue-yuan and HE HUI(Huazhong Agricultural Ursiversity, Wuhan 430070 China)

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ＧｏｅｔｈｉｔｅＭｏｒｐｈｏｌｏｇｉｅｓｏｆＳｏｍｅＳｏｉｌｓｉｎＳｏｕｔｈｏｆＣｅｎｔｒａｌＣｈｉｎａ￥ＬＩＵＦＡＮ；ＸＵＦＥＮＧ－ＬＩＮ；ＬＩＸＵＥ－ＹＵＡＮａｎｄＨＥＨＵＩ（ＨｕａｚｈｏｎｇＡｇｒｉｃｕｌｔｕｒａｌＵｒｓｉｖｅｒｓｉｔｙ，Ｗｕｈ...

关键词： goethites morphology soils surface adsorption surface charge

基于计算几何和信息图谱的矿山地质环境遥感动态监测

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煤炭学报 2015年第1期40卷 160-166页

作者：武强李学渊中国矿业大学(北京)水害防治与水资源研究所北京100083

为进一步加强我国矿山地质环境的监管工作,利用遥感技术提取不同时期矿山地质环境现状信息,基于计算几何,给出两期矿山地质环境现状图形要素(相交多边形)的对称差分集和交集计算方法,即获取其面积增减和类型转移的空间信息和属性信息,... 详细信息

为进一步加强我国矿山地质环境的监管工作,利用遥感技术提取不同时期矿山地质环境现状信息,基于计算几何,给出两期矿山地质环境现状图形要素(相交多边形)的对称差分集和交集计算方法,即获取其面积增减和类型转移的空间信息和属性信息,经拓扑多边形构建实现矿山地质环境遥感动态监测,并辅以地学信息图谱展示其动态变化的时间过程和空间差异。以内蒙古准格尔旗煤矿区为例,采用2007年Quick Bird和2012年World View2遥感影像作为基、末期数据源,进行矿山地质环境动态监测,以期揭示研究区内变化信息的时-空演变规律,为矿业活动和环境治理提供信息和决策服务。

关键词：矿山地质环境遥感动态监测计算几何地学信息图谱

1.4-nm Intergrade Mineral in Soils of Snbtropical China:A Review

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Pedosphere 1995年第2期5卷 151-156页

作者： HE JI-ZHENG XU FENG-liN liU FAN and li xue-yuan(Huazhong Agricultural University, W’uhan.430070 (China)

This paper is a review of some advances in the studies on 1.4-nm intergrade mineral of soils in sub-tropical China. 1) 1.4-nm intergrade mineral occurs ubiquitously in soils of subtropical China. The 1.4-nmrnineral in red soil and yellow soil is mainly 1.4-nm intergrade mineral, and in acidic yellow-brown soil (pHlite alone or 1.4-nm intergrade mineral together with vermiculite. The distribution and thecontent of 1 .4-nm intergrade mineral in the mountain soils are more widespread and higher than those of thecorresponding soils in horizontal zone. 2) The interlayer material of 1.4-nin intergrade mineral ui these soilsappears to be hydroxy-Al polymers instead of hydroxy-Fe, proto-imogolite or kaolin-like material. There isa significant positive correlation between Al amount extracted from the soil with sodium citrate after DCBextraction and pH value of the citrate solution after the extraction. The citrate can also extract a certainamount of silicon from the soil, but the silicon may not come from interlayer of 1.4-nm intergrade mineral.3) It was seldom studied that either vermiculite or smectite did the natural 1.4-nm intergrade mineral comefrom in soil, or it was commonly thought to come from vermiculite. A recent report has revealed that itcan come from smectite. There are some different behaviors between the 1.4-nm intergrade mineral derivedfrom vermiculite and that from smectite. For example, they exert different influences on the formation ofgibbsite. The 1.4-nm intergrade mineral derived from smectite may promote the formation of gibbsite in theyellow soil. 4) The type of 1.4-nm minerals in soils. i.e., vermiculite or 1.4-nm intergrade mineral, may besignificant to soil properties, such as soil acidity, exchangeable Al, electric charge aiiiount and specifi

关键词： interlayer material 1.4-nm intergrade mineral subtropical soil surface property

弹流润滑状态下渐开线斜齿轮啮合损失解析模型研究

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北京理工大学学报 2015年第7期35卷 682-686页

作者：胡纪滨李岩李雪原北京理工大学车辆传动国家级重点实验室北京100081

为了得到更简便的齿轮啮合损失计算方法,以渐开线斜齿轮为研究对象,结合弹流润滑理论和最小弹性势能原理,提出了一种新的齿轮啮合损失解析模型.基于对仿真结果的分析及采用单参数齿轮台架试验方法得到的试验曲线,揭示了齿轮箱转速及转... 详细信息

为了得到更简便的齿轮啮合损失计算方法,以渐开线斜齿轮为研究对象,结合弹流润滑理论和最小弹性势能原理,提出了一种新的齿轮啮合损失解析模型.基于对仿真结果的分析及采用单参数齿轮台架试验方法得到的试验曲线,揭示了齿轮箱转速及转矩对其传动效率的影响规律.针对高速重载工况,依据线性回归的理论,提出了斜齿轮啮合损失的解析模型.由解析模型可知:齿轮的啮合损失与齿轮转速的对数分布呈二次曲线变化,与齿轮转矩的对数分布呈线性变化;解析模型与原始数据吻合度较高;能够较快捷地得到高速重载变速箱的效率,且结果在可接受范围内.

关键词：弹流润滑解析模型啮合损失

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轮式车辆速差转向过程的转向阻力特性

兵工学报 2011年第12期32卷 1433-1438页

作者：李雪原张宇胡纪滨苑士华北京理工大学车辆传动国家重点实验室北京100081

研究了轮式速差转向车辆的转向阻力特性,运用离散单元方法(DEM)分析速差转向过程中轮胎与地面的相互作用,使用PFC2D软件建立轮胎侧向离散元细观仿真模型,得到转向阻力与相对滑移速度、下陷深度的数值关系。在此基础上,给出了轮胎转向阻... 详细信息

研究了轮式速差转向车辆的转向阻力特性,运用离散单元方法(DEM)分析速差转向过程中轮胎与地面的相互作用,使用PFC2D软件建立轮胎侧向离散元细观仿真模型,得到转向阻力与相对滑移速度、下陷深度的数值关系。在此基础上,给出了轮胎转向阻力系数的拟合公式。仿真结果表明,轮胎推土阻力远大于轮胎与地面之间的摩擦力。

关键词：公路运输速差转向地面力学离散单元法转向阻力

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斜轴式液压变压器变压比的影响因素分析

兵工学报 2012年第7期33卷 793-798页

作者：李雪原苑士华胡纪滨魏超北京理工大学车辆传动重点试验室北京100081

建立了斜轴式液压变压器的排量模型、转矩模型和变压比模型,分别推导出变压比与补油口压力、负载口流量以及油液粘度的导数关系式,在此基础上,得到了这些因素对变压比的影响特性。理论分析与试验结果表明:补油口压力对变压比的作用受配... 详细信息

建立了斜轴式液压变压器的排量模型、转矩模型和变压比模型,分别推导出变压比与补油口压力、负载口流量以及油液粘度的导数关系式,在此基础上,得到了这些因素对变压比的影响特性。理论分析与试验结果表明:补油口压力对变压比的作用受配流盘转角的影响,在不同的配流盘转角下,补油口压力的增大可能会提高或减小变压比,也有可能不影响变压比;增大负载口流量会减小变压比,而减小油液粘度会提高变压比;液压变压器变压过程中存在一个最大变压比点,而且负载口流量越大,最大变压比点出现越早。

关键词：流体传动与控制液压变压器变压比油液粘度

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我国东、中、西部地区经济差异分析

特区经济 2009年第11期 22-24页

作者：李雪苑商丘师范学院经济学与管理学系河南商丘476000

当前,我国东、中、西部地区经济呈现非均衡发展态势,从产业结构、人均GDP、城乡居民收入、FDI等各项指标可以看出地区间存在着经济差异,虽然近年来经济差异受到重视并有一定程度的改变,但在短期内很难消除甚至有扩大的趋势。垂直型区域... 详细信息

当前,我国东、中、西部地区经济呈现非均衡发展态势,从产业结构、人均GDP、城乡居民收入、FDI等各项指标可以看出地区间存在着经济差异,虽然近年来经济差异受到重视并有一定程度的改变,但在短期内很难消除甚至有扩大的趋势。垂直型区域产业分工、地理环境、人力资本的差异、市场失灵以及政策的倾斜等是造成这种差异的主要原因。

关键词：东、中、西部地区经济差异分析