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Lamprophyre or Lamproite Dyke in the S WTarim Block? —Discussion on the Petrogenesis of These Rocks and Their Source Region
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作者 柴凤梅 张招崇 +6 位作者 毛景文 帕拉提.阿布都卡迪尔 汪立今 董连慧 叶会寿 陈莉 郑蓉芬 《Journal of China University of Geosciences》 SCIE CSCD 2006年第1期13-24,共12页
The mineralogical, petrological and geochemical studies on Keliyang (克里阳) potassic dykes have been carried out to understand their rock types, the petrogenesis and the nature of their mantle sources. They arc pot... The mineralogical, petrological and geochemical studies on Keliyang (克里阳) potassic dykes have been carried out to understand their rock types, the petrogenesis and the nature of their mantle sources. They arc potassic lamprophyre, not lamproites as the previous researchers believed. In this study, the whole-rock major and trace element compositions of another 6 lamproite dykes recently discovered are reported. Major elements were determined by X-ray fluorescence spectrometry (XRF) techniques, while REE and trace elements were determined by inductively coupled plasma mass spectrometry (ICP-MS). They can be classified into phlogopite-diopside lamprophyre, leucite-diopside lamprophyre and granular carbonatite-bearing diopside lamprophyre on the basis of their mineral components. They are all characterized by relatively low SiO2 (41.31% --44. 84% ), TIO2 (0.75%-0.86% ) and high MgO (7.30%-11.33%), K2O (4.01%-6.01%) concentrations with K2O/Na2O ratios of 2.77-12.49. In addition, they display enrichment in large-ion lithophile elements (LILEs, e. g., Rb, Sr, Ba) and LREE, but a relative depletion in high-field-strength elements (HFSEs, e.g. , Nb, Ta, Zr, Hf and Ti). They display similar chondrite-normalized REE patterns with slight negative Eu anomalies (δEu=0.64-0.82), and high initial ^87 Sr/^86Sr ratios, which resemble those of high K/Ti and Iow-Ti potassic magmas formed in subduction-related settings. Consequently, we suggest that the parental magma was generated by partial melting of the phlogopite-amphibole-bearing garnet lherzolite within the lithospheric mantle that might have been metasomatized by a potassium-bearing fluid released from a sabdaction oceanic crust. 展开更多
关键词 potassic lamprophyre geochemistry mantle source region southwest boundary of Tarim
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A global land cover map produced through integrating multi-source datasets 被引量:5
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作者 Min Feng Yan Bai 《Big Earth Data》 EI 2019年第3期191-219,共29页
In the past decades,global land cover datasets have been produced but also been criticized for their low accuracies,which have been affecting the applications of these datasets.Producing a new global dataset requires ... In the past decades,global land cover datasets have been produced but also been criticized for their low accuracies,which have been affecting the applications of these datasets.Producing a new global dataset requires a tremendous amount of efforts;however,it is also possible to improve the accuracy of global land cover mapping by fusing the existing datasets.A decision-fuse method was developed based on fuzzy logic to quantify the consistencies and uncertainties of the existing datasets and then aggregated to provide the most certain estimation.The method was applied to produce a 1-km global land cover map(SYNLCover)by integrating five global land cover datasets and three global datasets of tree cover and croplands.Efforts were carried out to assess the quality:1)inter-comparison of the datasets revealed that the SYNLCover dataset had higher consistency than these input global land cover datasets,suggesting that the data fusion method reduced the disagreement among the input datasets;2)quality assessment using the human-interpreted reference dataset reported the highest accuracy in the fused SYNLCover dataset,which had an overall accuracy of 71.1%,in contrast to the overall accuracy between 48.6%and 68.9%for the other global land cover datasets. 展开更多
关键词 Global land cover data integration accuracy evaluation
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X波段测雨雷达系统建设与在山洪预警中的应用 被引量:4
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作者 李辉 褚泽帆 +1 位作者 刘娜 符伟杰 《电子设计工程》 2018年第8期52-56,共5页
为了实现测雨雷达在水文中的应用,研究高时空分辨率且空间连续的实时雨量监测方法,本文介绍了X波段高分辨雨量雷达系统性能指标及选址条件,并基于GIS软件开发了雷达应用软件,解决了传统雨量站数据在时间和空间上不连续的问题。针对小流... 为了实现测雨雷达在水文中的应用,研究高时空分辨率且空间连续的实时雨量监测方法,本文介绍了X波段高分辨雨量雷达系统性能指标及选址条件,并基于GIS软件开发了雷达应用软件,解决了传统雨量站数据在时间和空间上不连续的问题。针对小流域山洪强降雨、短历时的特点,在大理选取3个典型流域作为试验区,实现X波段测雨雷达系统在山洪灾害预警中的应用,提高了小流域山洪灾害的预报水平。 展开更多
关键词 雨量雷达 GIS 山洪预警 小流域
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白藜芦醇纯化工艺研究进展 被引量:6
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作者 鄢玉芬 陶明宝 +4 位作者 杨森 任思晨 陈鸿平 刘友平 Chen Lin 《亚太传统医药》 2018年第6期83-87,共5页
白藜芦醇被誉为继紫杉醇后的绿色抗癌药物,对白藜芦醇的理化性质、大孔树脂法、高速逆流色谱法、分子印迹法、膜分离法、柱层析法、双水相萃取法以及各技术联用的纯化工艺进行综述,以期为其进一步研发提供一定参考。
关键词 白藜芦醇 抗毒素 理化性质 纯化
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Application of GPS technology to build a mine-subsidence observation station 被引量:16
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作者 LU Wei-cai CHENG Shi-guang +1 位作者 YANG Hai-sheng LIU Da-peng 《Journal of China University of Mining and Technology》 EI 2008年第3期377-380,共4页
We propose the design of an observation station to establish a reliable datum for displacement and deformation analysis at the first working-face subsidence observation station of Liuzhuang Mine. The design considers ... We propose the design of an observation station to establish a reliable datum for displacement and deformation analysis at the first working-face subsidence observation station of Liuzhuang Mine. The design considers various geologic and mining con-ditions. Having analyzed the aims of the joint survey and the comprehensive survey, we propose design principles, and work modes, for adopting GPS technology as the position measuring technique to be used in these two stages. Baseline vectors and spatial ad-justments of the GPS network were calculated after study of data processing and quality estimation methods. A coordinate system transformation and error estimates of the transformed GPS network data are discussed. The error estimates in all stages show that the GPS control network of the observation station has sufficient accuracy and is highly efficient. The network thus provides a reli-able datum for analyzing the laws of surface displacement and deformation induced by mining. 展开更多
关键词 全球定位系统 矿沉淀 观察站 质量检测 数据处理
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Elucidating the interaction of kansui and licorice by comparative plasma/tissue metabolomics and a heatmap with relative fold change 被引量:1
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作者 Yan-Yan Chen Juan Shen +10 位作者 Yu-Ping Tang Jin-Gao Yu Jing Wang Shi-Jun Yue Jie Yang Jia-Qian Chen Li-Mei Feng Zhen-Hua Zhu Wei-Wei Tao Li Zhang Jin-Ao Duan 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2019年第5期312-323,共12页
Although compatibility is highly advocated in traditional Chinese medicine (TCM), inappropriate combination of some herbs may reduce the therapeutic action and even produce toxic effects. Kansui and licorice, one of T... Although compatibility is highly advocated in traditional Chinese medicine (TCM), inappropriate combination of some herbs may reduce the therapeutic action and even produce toxic effects. Kansui and licorice, one of TCM “Eighteen Incompatible Medicaments”, are the most representative cases of improper herbal combination, which may still be applied simultaneously under given conditions. However, the potential mechanism of their compatibility and incompatibility is unclear. In the present study, two different ratios of kansui and licorice, representing their compatibility and incompatibility respectively, were designed to elucidate their interaction by comparative plasma/tissue metabolomics and a heatmap with relative fold change. As a result, glycocholic acid, prostaglandin F2a, dihydroceramide and sphinganine were screened out as the principal alternative biomarkers of compatibility group;sphinganine, dihydroceramide, arachidonic acid, leukotriene B4, acetoacetic acid and linoleic acid were those of incompatibility group. Based on the values of biomarkers in each tissue, the liver was identified as the compatible target organ, while the heart, liver, and kidney were the incompatible target organs. Furthermore, important pathways for compatibility and incompatibility were also constructed. These results help us to better understand and utilize the two herbs, and the study was the first to reveal some innate characters of herbs related to TCM “Eighteen Incompatible Medicaments”. 展开更多
关键词 COMPARATIVE metabolomics Kansui LICORICE INCOMPATIBILITY Heatmap
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我国经济林资源的现状及其发展对策 被引量:2
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作者 崔凤敏 《农业灾害研究》 2021年第10期123-124,共2页
经济林的建设不仅可以改善人们居住的生态环境,而且可以为人们提供多种营养丰富的食品,促进地方经济发展。主要探讨了我国经济林资源的现状及其发展对策。
关键词 经济林资源 现状 发展对策
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全缘叶绿绒蒿总黄酮和总生物碱的提取工艺研究 被引量:1
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作者 余迎香 王岩 +2 位作者 刘明珠 暨迪军 卢永昌 《种业导刊》 2021年第4期3-7,共5页
采用响应面法和正交试验法,优化全缘叶绿绒蒿中总黄酮和总生物碱的提取工艺。结果表明,响应面法优化全缘叶绿绒蒿总黄酮的提取条件:乙醇体积分数60%、液料比25∶1(mL∶g)、提取时间1.5 h;正交试验法优化总生物碱的提取条件:超声功率120 ... 采用响应面法和正交试验法,优化全缘叶绿绒蒿中总黄酮和总生物碱的提取工艺。结果表明,响应面法优化全缘叶绿绒蒿总黄酮的提取条件:乙醇体积分数60%、液料比25∶1(mL∶g)、提取时间1.5 h;正交试验法优化总生物碱的提取条件:超声功率120 W、温度40℃、液料比30∶1(mL∶g)。建立的全缘叶绿绒蒿中总黄酮和总生物碱含量测定方法准确、重现性好,可作为全缘叶绿绒蒿药材质量评价的依据。 展开更多
关键词 全缘叶绿绒蒿 总黄酮 总生物碱 响应面法 正交试验法
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The Main Insect Pests of Safflower on Various Plant Parts in Iran
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作者 Mehdi Nasr Esfahani Giti Alizadeh Zahra Zarei Mohamad Nasr Esfahani 《Journal of Agricultural Science and Technology(A)》 2012年第11期1281-1288,共8页
关键词 红花 害虫 伊朗 植物 甜菜夜蛾 经济损失 小绿叶蝉 二斑叶螨
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Enhanced Biodegradation of High-Salinity and Low- Temperature Crude-Oil Wastewater by Immobilized Crude-Oil Biodegrading Microbiota
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作者 HUANG Xiao ZHOU Ting +2 位作者 CHEN Xi BAI Jie ZHAO Yangguo 《Journal of Ocean University of China》 SCIE CAS CSCD 2022年第1期141-151,共11页
High salt and low temperature are the bottlenecks for the remove of oil contaminants by enriched crude-oil degrading microbiota in Liaohe Estuarine Wetland(LEW),China.To improve the performance of crude-oil removal,mi... High salt and low temperature are the bottlenecks for the remove of oil contaminants by enriched crude-oil degrading microbiota in Liaohe Estuarine Wetland(LEW),China.To improve the performance of crude-oil removal,microbiota was further immobilized by two methods,i.e.,sodium alginate(SA),and polyvinyl alcohol and sodium alginate(PVA+SA).Results showed that the crude oil was effectively removed by the enrichment with an average degrading ratio of 19.42-31.45 mg(L d)^(−1).The optimal inoculum size for the n-alkanes removal was 10%and 99.89%.Some members of genera Acinetobacter,Actinophytocola,Aquabac-terium,Dysgonomonas,Frigidibacter,Sphingobium,Serpens,and Pseudomonas dominated in crude-oil degrading microflora.Though the removal efficiency was lower than free bacteria when the temperature was 15℃,SA and PVA+SA immobilization im-proved the resistance to salinity.The composite crude-oil degrading microbiota in this study demonstrated a perspective potential for crude oil removal from surface water under high salinity and low temperature conditions. 展开更多
关键词 crude-oil degrading microbiota microbial community immobilization high salinity low temperature
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如何成为药店的金牌供应商
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作者 王琳琳 《中国药店》 2011年第12期58-60,共3页
第十一届中国药店高峰论坛期间,“2010~2011年度中国药店十大金牌供应商”名单新鲜出炉。这一结果是根据中国药店杂志社和致联必达信息咨询有限公司(URC)联合开展的“中国药店供应商满意度全国调查活动”而评选的。
关键词 供应商 药店 金牌 高峰论坛 信息咨询 中国 满意度 杂志社
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The SPLASH Action Group—Towards standardized sampling strategies in permafrost science
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作者 Frederic BOUCHARD Yannick AGNAN +3 位作者 Lisa BRODER Julien FOUCHE Catherine HIRST Ylva SJOBERG 《Advances in Polar Science》 CSCD 2020年第3期153-155,共3页
The Action Group called‘Standardized methods across Permafrost Landscapes:from Arctic Soils to Hydrosystems’(SPLASH)is a community-driven effort aiming to provide a suite of standardized field strategies for samplin... The Action Group called‘Standardized methods across Permafrost Landscapes:from Arctic Soils to Hydrosystems’(SPLASH)is a community-driven effort aiming to provide a suite of standardized field strategies for sampling mineral and organic components in soils,sediments,and water across permafrost landscapes.This unified approach will allow data from different landscape interfaces,field locations and seasons to be shared and compared,thus improving our understanding of the processes occurring during lateral transport in circumpolar Arctic watersheds. 展开更多
关键词 BIOGEOCHEMISTRY SOILS organic matter MINERALS lateral transport aquatic systems
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Last glacial terrestrial vegetation record of leaf wax n-alkanols in the northern South China Sea:Contrast to scenarios from longchain n-alkanes
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作者 Shengyi Mao Guodong Jia +4 位作者 Xiaowei Zhu Nengyou Wu Daidai Wu Hongxiang Guan Lihua Liu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2022年第8期22-30,共9页
Long-chain n-alkanols and n-alkanes in core sediments from the northern South China Sea(SCS)were measured to make a comparison during terrestrial vegetation reconstruction from~42 ka to~7 ka.The results showed that te... Long-chain n-alkanols and n-alkanes in core sediments from the northern South China Sea(SCS)were measured to make a comparison during terrestrial vegetation reconstruction from~42 ka to~7 ka.The results showed that terrestrial vegetation record from long-chain n-alkanes matched well with previous studies in nearby cores,showing that more C_(4)plants developed during the Last Glacial Maximum(LGM)and C_(3)plants dominated in the interglacial period.However,these scenarios were not revealed by terrestrial vegetation reconstruction using long-chain n-alkanols,which showed C_(3)plant expansion during the LGM.The discrepancy during the interglacial period could be attributed to the aerobic degradation of functionalized long-chain n-alkanols in the oxygen-rich bottom water,resulting in poor preservation of terrestrial vegetation signals.On the other hand,the different advantages of functionalized n-alkanols and non-functional n-alkanes to record local and distal vegetation signals,respectively,may offer a potential explanation for the contradiction during the LGM when the SCS was characterized by low-oxygen deep water.Nevertheless,large variations on n-alkyl lipid compositions in C_(3)/C_(4)plants could play a part in modulating sedimentary long-chain n-alkanols and n-alkanes toward different vegetation signals,thereby suggesting that caution must be taken in respect to the terrestrial vegetation reconstruction using long-chain n-alkanes and long-chain n-alkanols. 展开更多
关键词 South China Sea long-chain n-alkanols long-chain n-alkanes Last Glacial Maximum terrestrial vegetation record
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Implicit Hypotheses Are Hidden Power Droppers in Family-Based Association Studies of Secondary Outcomes
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作者 Jean Gaschignard Quentin BVincent +2 位作者 Jean-Philippe Jais Aurelie Cobat Alexandre Alcais 《Open Journal of Statistics》 2015年第1期35-45,共11页
Family-based tests of association between a genetic marker and a disease constitute a common design to dissect the genetic architecture of complex traits. The FBAT software is one of the most popular tools to perform ... Family-based tests of association between a genetic marker and a disease constitute a common design to dissect the genetic architecture of complex traits. The FBAT software is one of the most popular tools to perform such studies. However, researchers are also often interested in the genetic contribution to a more specific manifestation of the phenotype (e.g. severe vs. non-severe form) known as a secondary outcome. Here, what we demonstrate is the limited power of the classical formulation of the FBAT statistic to detect the effect of genetic variants that influence a secondary outcome, in particular when these variants also impact on the onset of the disease, the primary outcome. We prove that this loss of power is driven by an implicit hypothesis, and we propose a derivation of the original FBAT statistic, free from this implicit hypothesis. Finally, we demonstrate analytically that our new statistic is robust and more powerful than FBAT for the detection of association between a genetic variant and a secondary outcome. 展开更多
关键词 Family-Based Association Test FBAT Genetic Association Studies Null Hypothesis Secondary Outcome Homogeneity Test
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Designing ABC-6 family small pore zeolites by epitaxial growth approach
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作者 Xiaohui Cui Jia Lv +5 位作者 Chao Ma Yujiao Wang Zhenghao Jia Daliang Zhang Peng Guo Zhongmin Liu 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第3期508-512,共5页
Aluminosilicate small pore zeolites belonging to ABC-6 family play crucially important roles in the high methanol conversion with the high selectivity of light olefins,gas separation and storage,and selective catalyti... Aluminosilicate small pore zeolites belonging to ABC-6 family play crucially important roles in the high methanol conversion with the high selectivity of light olefins,gas separation and storage,and selective catalytic reduction of NO_(x).In this work,we report a general method,called the epitaxial growth approach,for designing ABC-6 family small pore zeolites.It is mainly realized through the epitaxial growth on the nonporous SOD-type zeolite in the presence of inorganic cations(Na^(+)and K^(+))combined with a variety of organic structure directing agents(OSDAs).In this case,a series of ABC-6 family small pore zeolites such as ERI-,SWY-,LEV-,AFX-,and PTT-type zeolites have been successfully synthesized within a few hours.More importantly,the advanced focused ion beam(FIB)and the low-dose high-resolution transmission electron microscopy(HRTEM)imaging technique have been utilized for unraveling the zeolite heterojunction at the atomic level during the epitaxial growth process.It turns out(222)crystallographic planes of the SOD-type zeolite substrate provide unique pre-building units,which facilitate the growth of targeted ABC-6 family small pore zeolites along its c-axis.Moreover,the morphologies of ERI-type zeolite can also be tuned through the epitaxial growth approach,achieving a longer lifetime in the methanol conversion. 展开更多
关键词 Zeolite structure Zeolite synthesis Structural characterizations Low-dose imaging Focused ion beam
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苜蓿种植对矿山荒漠土微生物群落、酶活性及养分的影响
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作者 李玲 单成方 +1 位作者 吴挡 徐娟 《天津师范大学学报(自然科学版)》 CAS 2024年第3期37-44,共8页
为了探究苜蓿种植对矿山荒漠土的改良效应,采用16S rRNA高通量测序、冗余分析(RDA)和相关性分析等方法,分析未种植苜蓿(M0)、种植苜蓿4 a(M4)和5 a(M5)矿山荒漠土的微生物群落特征、酶活性及养分含量等.结果表明:(1) 3种处理下土壤的微... 为了探究苜蓿种植对矿山荒漠土的改良效应,采用16S rRNA高通量测序、冗余分析(RDA)和相关性分析等方法,分析未种植苜蓿(M0)、种植苜蓿4 a(M4)和5 a(M5)矿山荒漠土的微生物群落特征、酶活性及养分含量等.结果表明:(1) 3种处理下土壤的微生物Sobs、Chao指数由小到大为M0<M5<M4,M5的Shannon指数最低、Simpson指数最高;M4和M5的优势菌门是放线菌门、变形菌门和绿弯菌门,M0的优势菌门是放线菌门和绿弯菌门.(2)种植苜蓿后的矿山荒漠土碱性磷酸酶和脲酶活性增强,过氧化氢酶和蔗糖酶活性减弱;碱解氮、有效磷、速效钾和有机质含量由小到大依次为M0 <M5 <M4.(3)种植苜蓿后土壤中放线菌门和绿弯菌门丰度降低,且与养分含量呈负相关,而变形菌门丰度增加,且与养分含量呈正相关;酸杆菌门相对丰度升高,拟杆菌门相对丰度降低;参与化能异养、光能自养及碳、氮循环过程的代谢细菌丰度增加.综上,种植苜蓿可以增加矿山荒漠土的细菌总量、改变优势菌门丰度、增强细菌代谢功能,从而有效提高土壤质量. 展开更多
关键词 苜蓿 微生物群落 酶活性 养分 矿山荒漠土
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退耕还林(草)工程实施以来降水利用效率演变格局及归因——以宝鸡地区为例 被引量:7
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作者 王静 姚顺波 刘天军 《干旱区研究》 CSCD 北大核心 2020年第5期1233-1245,共13页
基于植被降水利用效率(rainfall use efficiency,RUE)模型,综合气候、土地利用/覆盖及光学遥感3个维度,分离人为干预(增加/减少)因素,监测生长季RUE时空演变特征,进一步采用地理探测器法探讨其驱动力。结果显示:(1)宝鸡地区经过两轮退... 基于植被降水利用效率(rainfall use efficiency,RUE)模型,综合气候、土地利用/覆盖及光学遥感3个维度,分离人为干预(增加/减少)因素,监测生长季RUE时空演变特征,进一步采用地理探测器法探讨其驱动力。结果显示:(1)宝鸡地区经过两轮退耕还林(草)工程,RUE整体上呈提高趋势,尤其是第一轮后(2009—2013年)呈显著提高趋势的像元面积占比最高,达65.69%。全区由第一轮工程实施下(2001—2008年)的以人为干预增加区域为主转变为以人为干预减少为主;(2)夏季降水量最为充裕,春季雨量较差,表现为夏季RUE的提高速率[0.07·(10a)-1]和春季RUE的降低速率[-0.06·(10a)-1]均最为显著。年际、夏秋季,林地的RUE值最高,春季城乡用地的RUE值最高;(3)植被覆盖率、相对湿度、日照时数、粮食总产量、最大风速、降水量、气温、人口密度、造林面积对RUE的相关性依次递减(置信水平95%),植被类型、坡度、坡向对RUE的相关性不显著。交互作用下RUE空间分布的相关性表现为:气候环境因素>自然资源因素>人类活动因素>地理环境因素。随着坡度的增加,RUE呈先增加后减少的变化趋势,在坡度26°~31°出现拐点;造林面积与RUE具有同步增减的变化趋势;植被对RUE的促进作用显著,人口密度对RUE的胁迫作用显著。此外,665.51~679.80 mm的降水量提高RUE的风险最高,集中于陈仓区东-西水平线区域上。 展开更多
关键词 退耕还林(草) RUE 人为干预 驱动力因子 宝鸡地区
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多年冻土区天然气管道工程:技术挑战和应对方案 被引量:4
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作者 李欣泽 金会军 《地球科学进展》 CAS CSCD 北大核心 2019年第11期1131-1140,共10页
多年冻土区油气管道工程在许多方面都有别于常温地区的油气管道工程,如偏僻的地理位置和敏感脆弱的环境,更重要是其特殊的气候、水文地质和工程地质条件以及冻融岩土灾害等条件。这使得管道设计、建设、运营、维抢和管道系统安全以及完... 多年冻土区油气管道工程在许多方面都有别于常温地区的油气管道工程,如偏僻的地理位置和敏感脆弱的环境,更重要是其特殊的气候、水文地质和工程地质条件以及冻融岩土灾害等条件。这使得管道设计、建设、运营、维抢和管道系统安全以及完整性管理等方面面临一系列的特殊难题。不同于已建成并运营至今的美国阿拉斯加(Alyeska)原油管道、加拿大罗曼井(Norman Wells)原油管道、中俄原油管道(漠河-大庆段)和格尔木-拉萨成品油管道,多年冻土区的天然气管道在输运介质、输送温度、环保要求等方面和输油管道有很大差异,将面临一系列新问题和新挑战。通过对多年冻土区天然气管道冷却输送工艺,管道-冻土水、热、力耦合计算,压气站失效后下游管道最低金属温度超限,基于应力设计局限、敷设方式单一、管道运营期监测系统可靠性等冻土区天然气管道特有的技术难题探讨,初步给出相应的解决方案构想,希望能够为冻土区天然气管道建设提供新的思路。 展开更多
关键词 输气管道 多年冻土 冷却输送工艺 管土水力热力耦合 基于应变的管道设计
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北京等地区草地贪夜蛾种群生物型鉴定 被引量:3
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作者 张子腾 谢爱婷 +3 位作者 董杰 杨建国 张爱环 王帅宇 《中国植保导刊》 北大核心 2021年第10期10-15,9,共7页
为明确草地贪夜蛾[Spodoptera frugiperda(J.E.Smith)]寄主生物型,对该虫进行精准监测及防控,采用分子标记方法,对采集于13省(市)29市(区)的83个草地贪夜蛾样本分别进行了COⅠ和Tpi基因片段的扩增和序列比对,以鉴定其寄主种群分化。CO... 为明确草地贪夜蛾[Spodoptera frugiperda(J.E.Smith)]寄主生物型,对该虫进行精准监测及防控,采用分子标记方法,对采集于13省(市)29市(区)的83个草地贪夜蛾样本分别进行了COⅠ和Tpi基因片段的扩增和序列比对,以鉴定其寄主种群分化。COⅠ基因序列比对结果显示,草地贪夜蛾水稻型占82%,玉米型占18%;Tpi基因的e4_(183)位点仅北京顺义的1个样本为玉米水稻杂合型,其余均为玉米型。结果表明,草地贪夜蛾是杂合群体,虫源为非单一性。目前以玉米型为主,但有进行水稻型分化的风险,可能对水稻生产造成威胁。 展开更多
关键词 草地贪夜蛾 分子标记 种群分化 玉米型 水稻型
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Chronic effects of different fertilization regimes on nirS-type denitrifier communities across the black soil region of Northeast China 被引量:4
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作者 Xiaojing HU Junjie LIU +7 位作者 Dan WEI Ping ZHU Xi'an CUI Baoku ZHOU Xueli CHEN Jian JIN Xiaobing LIU Guanghua WANG 《Pedosphere》 SCIE CAS CSCD 2020年第1期73-86,共14页
Denitrification is one of the major processes causing nitrogen loss from arable soils.This study aimed to investigate the responses of nir S-type denitrifier communities to different chronic fertilization regimes acro... Denitrification is one of the major processes causing nitrogen loss from arable soils.This study aimed to investigate the responses of nir S-type denitrifier communities to different chronic fertilization regimes across the black soil region of Northeast China.Soil samples were collected from sites located in the north(NB),middle(MB),and south(SB)of the black soil region of Northeast China,each with four chronic fertilization regimes:no fertilizer(No F),chemical fertilizer(CF),manure(M),and chemical fertilizer plus manure(CFM).Methods of quantitative polymerase chain reaction(q PCR)and Illumina Mi Seq sequencing were applied to assess the abundance and composition of denitrifier communities by targeting the nir S gene.The results showed that the M and CFM regimes significantly increased the abundances of nir S-type denitrifiers compared with No F at the three locations.The majority of nir S sequences were grouped as unclassified denitrifiers,and the different fertilizers induced little variation in the relative abundance of known nir S-type denitrifier taxa.Over 90%of the sequences were shared among the four fertilization regimes at each location,but none of the abundant operational taxonomic units(OTUs)were shared among the three locations.Principal coordinate analysis(PCo A)revealed that the communities of nir S-type denitrifier were separated into three groups that corresponded with their locations.Although similar fertilization regimes did not induce consistent changes in the nir S-type denitrifier communities,soil p H and NO-3-N content simultaneously and significantly influenced the structure of nir S-type denitrifier communities at the three locations.Our results highlight that geographical separation rather than chronic fertilization was the dominant factor determining the nir S-type denitrifier community structures,and similar chronic fertilization regimes did not induce consistent shifts of nir S-type denitrifier communities in the black soils. 展开更多
关键词 DENITRIFICATION denitrifier diversity denitrifying GENE geographical separation Illumina MiSeq sequencing MANURE MOLLISOLS nirS GENE quantitative POLYMERASE chain reaction
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