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荆门市小麦地稻草覆盖增产作用及机理

土壤肥料 2004年第5期 30-32,35页

作者：胡红青王清洲李淼泉陈燕华中农业大学资源与环境学院武汉430070 荆门市农业技术推广中心荆门448000

在荆门市白散土(黄棕壤发育的水稻土)上进行的田间小区试验表明,稻草覆盖小麦田后,土壤速效钾含量大幅提高,并能改善土壤理化性状,显著增加土壤含水量,调节地温,提高土壤肥力。覆草与对照相比,可明显增加小麦有效穗和千粒重,产量由不覆... 详细信息

在荆门市白散土(黄棕壤发育的水稻土)上进行的田间小区试验表明,稻草覆盖小麦田后,土壤速效钾含量大幅提高,并能改善土壤理化性状,显著增加土壤含水量,调节地温,提高土壤肥力。覆草与对照相比,可明显增加小麦有效穗和千粒重,产量由不覆盖的2.99 5kg/hm2.高到3558kg/hm2.实验室淋溶试验可看出,3小时后稻草中84%的钾就被淋溶出来。而在大田试验中4个月后,有90%的钾进入土壤。所以秸秆还田是缓解钾肥资源不足的一项有效措施,值得推广应用。

关键词：荆门市秸秆还田稻草覆盖

Precise isotopic measurements of sub-nanogram Nd of standard reference material by thermal ionization mass spectrometry using the NdO+ technique

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Precise isotopic measurements of sub-nanogram Nd of standard...

True Type格式“地质矿产符号库”特点介绍

中国科学院地质与地球物理研究所2.07学术年会

作者： Chao-Feng Li~(a,b,c),Fukun Chen~(a,c,*),Xiang-Hui Li~(a,b) a State Key Laboratory of Lithospheric Evolution,institute of Geology and Geophysics,Chinese academy of Sciences,{2. 10002.,China b School of Earth Sciences,Graduate University of Chinese academy of Sciences,{2. 100039,China c Laboratory for Radiogenic Isotope Geochemistry,institute of Geology and Geophysics,Chinese academy of Sciences,{2. 10002.,China

The Sm-Nd isotopic system,one of the important techniques for dating and geochemical tracing,has been widely used in *** and accurate measurements of Nd isotopic ratios are more difficult to achieve for microsamples that contain less than 50ng Nd,when routine Nd technique is applied on thermal ionization mass spectrometer(TIMS).Compared to Nd technique,the NdO technique,owing to more efficient ionization,is a better choice for high precision measurements of Nd isotopic ratios of micro- or low-content *** study presents measurement results of sub-nanogram size samples of standard reference solution and rock-powder using NdO technique on the latest TIMS (GV product IsoProbe-T).Sixteen rock-powder references and four reference solutions were measured both by NdO and Nd techniques for an evaluation of accuracy and precision of measurements obtained by the NdO *** show that analytical precision and reproducibility of NdO measurements of sub-nanogram Nd is comparable with those obtained by the Nd measurements of samples containing 2.0 ng *** precision of the Nd/Nd ratios achieved with both techniques is better than 0.003%.Our results show that the microsample NdO technique is a very promising method for high resolution Sm-Nd geochronology and isotopic tracing.

关键词： NdO+ technique Chromatography Sub-nanogram sample Isobaric interference

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吉林地质 2004年第2期23卷 69-71页

作者：刘冶兵王立民陈雷徐卫吉林省地质调查院吉林长春130061 吉林省区域地质矿产调查所吉林长春130022

"地质矿产符号库"是一套采用国际先进技术、符合国内行业标准的专业字库。具有4大特点,可用8个字概括:"美观、统一、规范、通用"。

关键词： TrueType格式空间数据库国家标准 “地质矿产符号库”

2.13—2.15年京津冀新增耕地时空特征与来源分析

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农业机械学报 2018年第3期49卷 205-213页

作者：杨建宇张婷婷陈正张超赵冬玲林尚纬中国农业大学信息与电气工程学院北京100083 国土资源部农用地质量与监控重点实验室北京100035 国土资源部土地整治中心北京100035

利用2.13—2.15年土地变更调查新增耕地数据,基于县域和区域两种尺度,运用重心模型、区位基尼系数、地理集中度以及统计分析等方法,分析3年京津冀地区新增耕地时空特征,并从不同来源对新增耕地状况进行深入解析,以期为京津冀后续建设尤... 详细信息

利用2.13—2.15年土地变更调查新增耕地数据,基于县域和区域两种尺度,运用重心模型、区位基尼系数、地理集中度以及统计分析等方法,分析3年京津冀地区新增耕地时空特征,并从不同来源对新增耕地状况进行深入解析,以期为京津冀后续建设尤其是雄安新区建设提供参考。研究结果表明:从2.13—2.15年京津冀新增耕地整体看,新增耕地主要集中在中东部平原区、西部山区和北部高原区3大区域;从不同年份分析,京津冀地区新增耕地面积先减后增,重心从京津冀东北方逐渐向西南方偏移,并呈高度聚集态势。新增水浇地是京津冀地区新增耕地的主要地类。新增耕地主要是通过农村土地整治新增耕地的方式而来,大部分来源于草地,生态问题愈发突出。最后,深入分析新增耕地时空变化规律,建议京津冀在未来建设中因地制宜,加大节水力度,注重生态文明建设。

关键词：京津冀地区土地整治新增耕地时空特征重心模型区位基尼系数

THE NEW CLASSIFICATIONS OF ROOF AND FLOOR AROUND COALFACE

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Journal of Coal Science & Engineering(China) 1995年第1期1卷 13-19页

作者： SHI Yuanwei(Central Coal Mining Research institute beijing, China)

This paper briefly describes the new principle about the classification of inimediate roof after its stabilities and main roof after the intensity of its weighing, as well as the floor based on its resistance and rigidity that are against supports to penetrate in coal face. These have been done on the basis of theory and measured data obtained from field observation. These classifications are very important for optimal determination of technique for control of surrounding rock-mass including the selection of supports, as well as the economic effect and safety during

关键词：煤层顶板管理分级法地层控制

Characteristics of N Mineralization in Urban Soils of Hefei,East China

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Pedosphere 2010年第2期20卷 236-244页

作者： ZHANG Kai,XU Xiao-Niu and WANG Qin School of forestry and Landscape Architecture,Anhui Agricultural University,Hefei 2.0036 (China) [a] School of forestry and Landscape Architecture Anhui Agricultural University Hefei 230036 (China)

Nitrogen cycling has been poorly characterized in urban *** in-situ buried bag incubation technique was used to quantify net rates of N mineralization and nitrification in soils of two urban sites,a street greening belt and a university campus,and a suburban site,a forest park,in Hefei,East *** average concentration of extractable NO 3 in the surface soil (0-10 cm) was significantly higher at the urban sites than the suburban park site,whereas extractable NH + 4 concentration was significantly higher at the suburban park site than the urban *** forest park soil had greater potential N mineralization (148.1 μg N cm 3) than the soils from the campus (138.3 μg N cm 3) and street (99.8 μg N cm 3).The net mineralization rates varied between 1.63 and 2.69 μg N cm 3 d 1 and net nitrification rates between 0.82.and 1.02.μg N cm 3 d 1 at the suburban forest park site,but the rates varied from 1.2. to 2.41 μg N cm 3 d 1 and from 1.07 to 1.49 μg N cm 3 d 1,respectively,at the urban campus *** net mineralization and nitrification rates were lower during dry *** from regression analysis indicated that net N mineralization was significantly and positively correlated with soil moisture and soil C/N ratio,and was negatively correlated with soil *** nitrification was,however,significantly and negatively correlated with soil moisture and soil C/N ratio,and was positively correlated with soil *** relative nitrification was 0.763,indicating the dominance of nitrate cycling relative to ammonium cycling at the urban *** urban soils had the great potential for N losses compared to the suburban soils.

关键词： nitrification nitrogen cycling soil properties

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等离子束辅助沉积制备ZnO薄膜的特性研究

四川大学学报（工程科学版） 2004年第6期36卷 77-81页

作者：甄万宝朱世富赵北君宋志棠封松林四川大学材料科学与工程学院四川成都610064 中科院上海微系统与信息技术研究所上海200050

采用等离子束辅助沉积的方法在n-Si(001)衬底上制备出ZnO薄膜。X射线衍射谱显示,所制备的ZnO薄膜有较强的(002.晶面衍射峰,表明ZnO薄膜为c轴择优取向生长的,并且随着退火温度升高,晶粒逐渐增大,衍射峰逐渐增强。光致发光谱测量发现,样... 详细信息

采用等离子束辅助沉积的方法在n-Si(001)衬底上制备出ZnO薄膜。X射线衍射谱显示,所制备的ZnO薄膜有较强的(002.晶面衍射峰,表明ZnO薄膜为c轴择优取向生长的,并且随着退火温度升高,晶粒逐渐增大,衍射峰逐渐增强。光致发光谱测量发现,样品分别在3.2.eV和2.48eV存在紫外发射和深能级发射两个较强的发射峰,并且随着退火温度升高,深能级发射逐渐减弱,紫外发射峰得到进一步改善。四探针测试电阻率结果表明,随着退火温度的升高,ZnO薄膜的电阻率呈线性增加。

关键词：等离子束辅助沉积光致发光 ZnO薄膜

INDUSTRIAL DEVELOPMENT AND CITY PLANNING IN THE CASE OF THE CHINESE COAL-MINING CITIES

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地理学报 1978年第1期33卷 78-79页

作者： Li Wen-yan(institute of Geography, academy Sinica) institute of Geography Academy Sinica.

ABSTRACT To study the law of emergence and growth of coal-mining cities, analysing their particular contradictions and problems and determining the orientation of their in-dustrial development, so as to adapt to local conditions, is quite essential in promo-ting comprehensive utilization of the natural resources, planned and proportionate development of regional economy and systematical distribution of the cities.

关键词： INDUSTRIAL DEVELOPMENT AND CITY PLANNING IN THE CASE OF THE CHINESE COAL-MINING CITIES

音猬因子的功能受体斑片在培养神经干细胞中的表达

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解剖学报 2002年第6期33卷 561-565页

作者：许汉鹏胡沛臻苟琳张萍鞠躬第四军医大学神经科学研究所第四军医大学病理学教研室第四军医大学航空临床医学教研室西安710032

目的　观察在培养的神经干细胞内是否有发育调控分子———音猬因子 (sonichedgehog)功能受体———斑片 (patched)表达。　方法　神经干细胞克隆在体外培养传代后 ,用patched的特异性引物对培养的神经干细胞进行RT PCR分析 ,PCR产物经... 详细信息

目的　观察在培养的神经干细胞内是否有发育调控分子———音猬因子 (sonichedgehog)功能受体———斑片 (patched)表达。　方法　神经干细胞克隆在体外培养传代后 ,用patched的特异性引物对培养的神经干细胞进行RT PCR分析 ,PCR产物经克隆测序后 ,用地高辛标记克隆的探针 ,对神经干细胞进行原位杂交分析。　结果　神经干细胞克隆内大量的细胞均可表达sonichedgehog的功能受体patched ,patched阳性细胞间未见明显差别 ,克隆边缘与中央的patched分布也未见明显差别。　结论　sonichedgehog信号传导路可能在神经干细胞的增殖与分化过程中起重要作用。

关键词：音猬因子功能受体斑片神经干细胞细胞培养 RT-PCR 原位杂交