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A re-assessment of nickel-doping method in iron isotope analysis on rock samples using multi-collector inductively coupled plasma mass spectrometry 认领
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作者 Hongmei Gong Pengyuan Guo +4 位作者 Shuo Chen Meng Duan Pu Sun Xiaohong Wang Yaoling Niu 《中国地球化学学报:英文版》 EI CAS CSCD 2020年第3期355-364,共10页
Element doping has been proved to be a useful method to correct for the mass bias fractionation when analyzing iron isotope compositions.We present a systematic re-assessment on how the doped nickel may affect the iro... Element doping has been proved to be a useful method to correct for the mass bias fractionation when analyzing iron isotope compositions.We present a systematic re-assessment on how the doped nickel may affect the iron isotope analysis in this study by carrying out several experiments.We find three important factors that can affect the analytical results,including the Ni:Fe ratio in the analyte solutions,the match of the Ni:Fe ratio between the unknown sample and standard solutions,and the match of the Fe concentration between the sample and standard solutions.Thus,caution is required when adding Ni to the analyte Fe solutions before analysis.Using our method,theδ56Fe and δ57Fe values of the USGS standards W-2 a,BHVO-2,BCR-2,AGV-2 and GSP-2 are consistent with the recommended literature values,and the long-term(one year) external reproducibility is better than 0.03 and 0.05‰(2 SD) for δ56Fe and δ57Fe,respectively.Therefore,the analytical method established in our laboratory is a method of choice for high quantity Fe isotope data in geological materials. 展开更多
关键词 Fe isotope Ni-doping Stable isotope Precision and accuracy Mass bias correction Pseudohigh mass resolution
稳定同位素模型解析大气氨来源的参数敏感性 认领
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作者 顾梦娜 潘月鹏 +7 位作者 何月欣 田世丽 王彦君 吕雪梅 倪雪 孙杰 吴电明 方运霆 《环境科学》 EI CAS CSCD 北大核心 2020年第7期3095-3101,共7页
氨(NH3)是大气霾污染和过量氮沉降的关键前体物,准确厘清其来源是制定NH3减排策略的科学基础.稳定同位素模型(SIAR)在NH3溯源研究中展现出巨大潜力,其解析结果的可靠性与NH3排放源的氮同位素指纹谱(δ15N-NH3)密切相关.本研究基于2013年... 氨(NH3)是大气霾污染和过量氮沉降的关键前体物,准确厘清其来源是制定NH3减排策略的科学基础.稳定同位素模型(SIAR)在NH3溯源研究中展现出巨大潜力,其解析结果的可靠性与NH3排放源的氮同位素指纹谱(δ15N-NH3)密切相关.本研究基于2013年1月北京霾污染期间的同位素观测资料,使用SIAR评估了3个重要源谱参数(源的数量、源的δ15N-NH3特征值及其标准差)对NH3源解析的影响.结果表明,农业源的贡献率对源谱δ15N-NH3特征值的变化最敏感,其次为化石燃烧源,氨逃逸源的敏感性最低.农业源δ15N-NH3标准差的改变仅造成农业源贡献率变化约4%,但其特征值的改变却造成农业源贡献率20%的变化.相比之下,将农业源拆分为化肥挥发和畜牧养殖源后,解析结果并未显著增加农业源的总贡献,即"非农业源"仍然是2013年初北京霾污染期间NH3的重要来源.考虑到农业源的贡献率对SIAR模型参数改变的响应最为敏感,且不同类型的农业源δ15N-NH3差异较大,未来需要针对农业源δ15N-NH3的时空变化规律及影响因素开展深入研究,以此来降低同位素源解析模型的不确定性. 展开更多
关键词 氨气 同位素 源谱 稳定同位素模型(SIAR) 源解析
Habitat Influence on the Molecular, Carbon and Hydrogen Isotope Compositions of Leaf Wax n-Alkanes in a Subalpine Basin, Central China 认领
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作者 Chaoyang Yan Yiming Zhang +2 位作者 Yanzhen Zhang Zhiqi Zhang Xianyu Huang 《地球科学学刊:英文版》 SCIE CAS CSCD 2020年第4期845-852,共8页
Epidermal leaf waxes of terrestrial higher plants have been widely utilized for the reconstructions of paleoenvironment and paleoclimate in peat deposits. In this study, specimens of four plant species growing in both... Epidermal leaf waxes of terrestrial higher plants have been widely utilized for the reconstructions of paleoenvironment and paleoclimate in peat deposits. In this study, specimens of four plant species growing in both peatland and non-peatland habitats were retrieved to compare their molecular, carbon(δ13 C) and hydrogen(δ2 H) isotopic compositions of leaf wax n-alkanes from a closed subalpine basin in Central China. Three of the four species show quite higher total concentrations of n-alkanes in the relatively dry non-peatland setting than in the peatland. In addition, the δ2 H values of long-chain n-alkanes are generally less depleted in the peatland and are comparable among different plant species, which is interpreted as the influence of inundation condition and the possible limited supply of photosynthetic products. This study reveals different patterns of plant wax molecular and isotopic compositions between peatland and the surrounding non-peatland conditions, and confirms the paleoenvironmental potential of leaf wax ratios on the peat sequences. 展开更多
关键词 HABITAT N-ALKANE compound specific carbon isotope compound specific hydrogen isotope peat deposit
辽东半岛青城子矿田典型金矿成因:来自硫、氢、氧同位素的证据 认领
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作者 赵岩 杨宏智 +3 位作者 杨凤超 张朋 顾玉超 胥嘉 《地质与资源》 CAS 2020年第1期21-28,共8页
青城子矿田是辽宁东部重要的金多金属矿田,成矿作用复杂.选择白云金矿和小佟家堡子金矿进行了硫同位素和氢氧同位素研究.结果显示矿田内小佟家堡子等金矿硫同位素含量为1.87‰~16‰,无明显的塔式分布;白云金矿的硫同位素含量为-10.3‰~+... 青城子矿田是辽宁东部重要的金多金属矿田,成矿作用复杂.选择白云金矿和小佟家堡子金矿进行了硫同位素和氢氧同位素研究.结果显示矿田内小佟家堡子等金矿硫同位素含量为1.87‰~16‰,无明显的塔式分布;白云金矿的硫同位素含量为-10.3‰~+1.9‰.氢氧同位素测试结果显示白云金矿中石英δD含量为-108.3‰~-74‰,δ18O含量为8‰~15.9‰;而小佟家堡子等金矿的石英氢氧同位素分布则较为分散.综合分析认为,小佟家堡子金矿代表了早期金成矿,与变质作用有关;白云金矿代表了晚期金成矿作用;矿田内层状铅锌矿与小佟家堡子等金矿可能是同期成矿事件. 展开更多
关键词 硫同位素 氢氧同位素 青城子矿田 白云金矿 小佟家堡子金矿 辽宁东部
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内蒙古鸡冠山斑岩型钼矿床S、Pb同位素组成:对成矿物质来源的指示 认领
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作者 陈伟军 褚少雄 +2 位作者 刘建明 刘红涛 曾庆栋 《地质与勘探》 CAS CSCD 北大核心 2020年第1期68-77,共10页
内蒙古鸡冠山钼矿床位于中亚-蒙古巨型造山带东段,是西拉沐沦钼金属成矿带中典型的大型斑岩型钼矿床。矿床产于燕山晚期火山侵入杂岩中,矿体与岩体关系密切,矿化类型以细脉浸染状斑岩型矿化为主。在野外地质观察的基础上,本文对矿石矿... 内蒙古鸡冠山钼矿床位于中亚-蒙古巨型造山带东段,是西拉沐沦钼金属成矿带中典型的大型斑岩型钼矿床。矿床产于燕山晚期火山侵入杂岩中,矿体与岩体关系密切,矿化类型以细脉浸染状斑岩型矿化为主。在野外地质观察的基础上,本文对矿石矿物黄铁矿、辉钼矿进行了S同位素组成分析,对矿床围岩全岩及黄铁矿单矿物进行了Pb同位素组成分析。结果表明,钼矿石δ34 S变化范围为4.617‰~7.072‰,平均值为5.653‰,离散度小,硫化物δ34 S值全为正值,表明矿石中S源是均一的。辉钼矿δ34 S变化范围为4.617‰~5.351‰,平均值为4.875‰。硫同位素比值5.653‰具花岗质岩浆硫特征,推测其硫可能主要来源于下地壳岩浆源,并有一定量的地幔物质混入。全岩的206 Pb/204 Pb、207 Pb/204 Pb和208 Pb/204 Pb分别为17.876~19.618、15.519~15.609和38.111~40.408,表明鸡冠山钼矿床围岩的全岩铅同位素组成均变化较大。矿石矿物黄铁矿的206 Pb/204 Pb、207 Pb/204 Pb和208 Pb/204 Pb分别为17.781~17.830、15.523~15.526和38.084~38.102,表明矿石矿物铅同位素组成变化较小。围岩全岩和矿石硫化物的铅同位素投影点均落在造山带演化线的下方,表明铅很可能源于地幔或者下地壳。 展开更多
关键词 成矿物质来源 S同位素 PB同位素 斑岩型钼矿床 鸡冠山 内蒙古
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The giant tin polymetallic mineralization in southwest China:Integrated geochemical and isotopic constraints and implications for Cretaceous tectonomagmatic event 认领
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作者 Yanbin Liu Lifei Zhang +3 位作者 Xuanxue Mo M.Santosh Guochen Dong Hongying Zhou 《地学前缘:英文版》 SCIE CAS CSCD 2020年第5期1593-1608,共16页
The Gejiu-Bozushan-Laojunshan W-Sn polymetallic metallogenic belt(GBLB)in southeast Yunnan Province is an important part of the southwestern Yangtze Block in South China.Tin polymetallic mineralization in this belt in... The Gejiu-Bozushan-Laojunshan W-Sn polymetallic metallogenic belt(GBLB)in southeast Yunnan Province is an important part of the southwestern Yangtze Block in South China.Tin polymetallic mineralization in this belt includes the Niusipo,Malage,Songshujiao,Laochang and Kafang ore fields in the Gejiu area which are spatially and temporally associated with the Kafang-Laochang and Songshujiao granite plutons.These granites are characterized by variable A/CNK values(mostly>1.1,except for two samples with 1.09),high contents of SiO2(74.38-76.84 wt.%)and Al2 O3(12.46-14.05 wt.%)and variable CaO/Na2 O ratios(0.2-0.65)as well as high zirconδ18O values(7.74‰-9.86‰),indicative of S-type affinities.These rocks are depleted in Rb,Th,U,Ti,LREE[(La/Yb)N=1.4-20.51],Ba,Nb,Sr,and Ti and display strong negative Eu and Ba anomalies.The rocks possess high Rb/Sr and Rb/Ba ratios,relatively low initial 87Sr/86Sr ratios(0.6917-0.7101),and less radiogenicεNd(t)values(-8.0 to-9.1).The zircon grains from these rocks show negativeεHf(t)values in the range of-3.7 to-9.9 with mean TDM2(Nd)and TDM2(Hf)values of 1.57 Ga and 1.55 Ga.They show initial 207Pb/204Pb ranging from15.69 to 15.71 and 206Pb/204Pb from 18.36 to 18.70.Monazite from Songshujiao granites exhibits higher U and lower Th/U ratios,lowerδ18O values and higherεHf(t)values than those of the zircon grains in the KafangLaochang granites.The geochemical and isotopic features indicate that the Laochang-Kafang granites originated by partial melting of Mesoproterozoic crustal components including biotite-rich metapelite and metagraywacke,whereas the Songshujiao granites were derived from Mesoproterozoic muscovite-rich metapelite crustal source.Most zircon grains from the Songshujiao,Laochang and Kafang granites have high-U concentrations and their SIMS U-Pb ages show age scatter from 81.6 Ma to 88.6 Ma,80.7 Ma to 86.1 Ma and 82.3 Ma to 87.0 Ma,suggesting formation earlier than the monazite and cassiterite.Monazite SIMS U-Pb ages and Th-Pb ages of three same granite samples are co 展开更多
关键词 S-type granite SIMS monazite and zircon geochronology Cassiterite U–Pb age Zircon Hf–O isotope Sr–Nd–Pb isotope Yangtze Block
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文章速递Carbon Sources of Sediment and Epifaunal Food Sources in a Tropical Mangrove Forest in North Sulawesi, Indonesia 认领
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作者 WU Zhiqiang XIE Limei +6 位作者 CHEN Bin DHAMAWAN I Wayan Eka SASTROSUWONDO Pramudji CHEN Shunyang RIANTA Pratiwi ERNAWATI Widyastuti CHEN Guangcheng 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2020年第5期1169-1176,共8页
The stable isotope ratios of nitrogen(δ~(15)N) and carbon(δ~(13)C) were applied in this study to analyze sediment carbon sources and primary food sources of epifauna in an oceanic mangrove forest in tropical North S... The stable isotope ratios of nitrogen(δ~(15)N) and carbon(δ~(13)C) were applied in this study to analyze sediment carbon sources and primary food sources of epifauna in an oceanic mangrove forest in tropical North Sulawesi, Indonesia. Proportional contribution of mangrove-derived carbon to the food sources was compared among epifauna belonging to different feeding guilds. The sediment in the mangrove site with a depleted δ~(13)C signature(-28.02‰± 0.24‰) mainly consists of mangrove-derived carbon. Analysis using Bayesian stable isotope mixing model in the R program shows that mangrove-derived carbon can dominate the food sources of a majority of the epifauna(11 out of the total 18 species), especially 2 sesarmid crabs Parasesarma semperi and Sesarma sp., crab Epixanthus dentatus, and snails Terebralia sulcata and Optediceros breviculum, which belong to various feeding guilds. Mangrove-derived carbon has a proportional contribution to the food sources of fiddle crab Tubuca coarctata and 3 littorinid snails(Littoraria spp.) close to that of suspended particulate organic matter. Three planktophagous bivalve species(Anadara antiquata, Anadara sp. and Callista erycina) were found to mainly feed on seagrass-derived materials. Mean proportional contributions of mangrove-derived carbon to the food sources were 50.15%, 59.60%, 46.20% and 27.58% for the carnivorous, omnivorous, phytophagous and planktophagous groups, respectively. The results suggest that mangrove-derived carbon can directly(via grazing plant tissues) or indirectly(via deposit feedings) make an important contribution to the food sources of epifauna in the oceanic mangrove forest where the allochthonous input of organic carbon is low. 展开更多
关键词 epifauna stable isotope carbon nitrogen sediment feeding guilds
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文章速递贵州息烽温泉水文地球化学特征及地质成因研究 认领
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作者 吉勤克补子 李强 +1 位作者 洪运胜 周亚男 《四川地质学报》 2020年第3期434-438,共5页
息烽温泉为贵州百年名泉,通过收集整理多年水质分析资料,系统阐述了温泉水文地球化学特征;采用同位素化学方法,分析了温泉补给来源、形成年龄及高程效应;利用Na-K-Mg三角图解判断温泉水属未成熟水,采用SiO2地热温标法估算出温泉热储温度... 息烽温泉为贵州百年名泉,通过收集整理多年水质分析资料,系统阐述了温泉水文地球化学特征;采用同位素化学方法,分析了温泉补给来源、形成年龄及高程效应;利用Na-K-Mg三角图解判断温泉水属未成熟水,采用SiO2地热温标法估算出温泉热储温度为101.92℃,热流体循环深度超过2500m;在综合分析基础上,提出息烽温泉地热水循环于洋水背斜西翼深埋藏于地下的震旦系上统灯影组Zbdn、板溪群清水江组Ptbnbq地层中,热流体从南西向北东径流,在息烽温泉处受F1断裂阻隔而沿断层带上升,在“低势点”出露成泉的地质成因模式。 展开更多
关键词 息烽温泉 水文地球化学特征 同位素 成因
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文章速递Geochemical characteristics and genetic mechanism of the high-N2 shale gas reservoir in the Longmaxi Formation, Dianqianbei Area, China 认领
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作者 Ji‑Lin Li Ting‑Shan Zhang +6 位作者 Yan‑Jun Li Xing Liang Xin Wang Jie‑Hui Zhang Zhao Zhang Hong‑Lin Shu Da‑Qian Rao 《石油科学:英文版》 SCIE CAS CSCD 2020年第4期939-953,共15页
As an important pilot target for shale gas exploration and development in China,the Longmaxi Formation shale in the Dianqianbei Area is characterized by high content of nitrogen,which severely increases exploration ri... As an important pilot target for shale gas exploration and development in China,the Longmaxi Formation shale in the Dianqianbei Area is characterized by high content of nitrogen,which severely increases exploration risk.Accordingly,this study explores the genesis of shale gas reservoir and the mechanism of nitrogen enrichment through investigating shale gas compositions,isotope features,and geochemical characteristics of associated gases.The high-nitrogen shale gas reservoir in the Longmaxi Formation is demonstrated to be a typical dry gas reservoir.Specifically,the alkane carbon isotope reversal is ascribed to the secondary cracking of crude oil and the Rayleigh fractionation induced by the basalt mantle plume.Such a thermogenic oil-type gas reservoir is composed of both oil-cracking gas and kerogen-cracking gas.The normally high nitrogen content(18.05%-40.92%) is attributed to organic matter cracking and thermal ammoniation in the high-maturity stage.Specifically,the high heat flow effect of the Emeishan mantle plume exacerbates the thermal cracking of organic matter in the Longmaxi Formation shale,accompanied by nitrogen generation.In comparison,the abnormally high nitrogen content(86.79%-98.54%) is ascribed to the communication between the atmosphere and deep underground fluids by deep faults,which results in hydrocarbon loss and nitrogen intrusion,acting as the key factor for deconstruction of the primary shale gas reservoir.Results of this study not only enrich research on genetic mechanism of high-maturity N_@ shale gas reservoirs,but also provide theoretical guidance for subsequent gas reservoir resource evaluation and well-drilling deployment in this area. 展开更多
关键词 Longmaxi Formation Shale gas reservoir Isotope High nitrogen content Genetic mechanism
松花江流域氮时空分布特征及源解析研究 认领
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作者 叶匡旻 孟凡生 +4 位作者 张铃松 姚志鹏 薛浩 程佩瑄 张道萍 《环境科学研究》 EI CAS CSCD 北大核心 2020年第4期901-910,共10页
松花江流域是我国氮污染较为严重的流域之一,为了研究松花江流域氮时空变化特征和主要来源,结合松花江流域2003—2018年国控断面NH 4+-N、TN及相关指标的监测数据和典型断面采样检测数据,采用季节性Kendall检验法分析了松花江流域ρ(NH4... 松花江流域是我国氮污染较为严重的流域之一,为了研究松花江流域氮时空变化特征和主要来源,结合松花江流域2003—2018年国控断面NH 4+-N、TN及相关指标的监测数据和典型断面采样检测数据,采用季节性Kendall检验法分析了松花江流域ρ(NH4^+-N)、ρ(TN)和ρ(COD Mn)的历史变化趋势,利用Origin 8.0软件绘制了ρ(NH4^+-N)、ρ(TN)和ρ(COD Mn)的沿程分布图及水期规律图,并采用氮氧稳定同位素技术解析了水体中氮的主要来源.结果表明:①松花江流域城市污染排放对水体氮浓度具有较大影响,城市下游断面氮浓度远高于城市上游断面,并且松花江流域支流氮浓度高于干流.②时间维度上,松花江流域水体中不同水文期ρ(NH4^+-N)和ρ(TN)变化规律为枯水期>平水期>丰水期,ρ(COD Mn)变化规律为枯水期<平水期<丰水期.③季节性Kendall检验法分析结果显示,松花江流域90.0%的断面ρ(NH4^+-N)呈下降趋势,62.5%的断面ρ(TN)呈上升趋势,且上升趋势断面主要集中在支流伊通河、阿什河上.④13个典型采样断面δ15 N-NO3(硝酸盐氮同位素)和δ18O-NO3(硝酸盐氧同位素)值域范围分别为1.52‰~11.15‰、-13.82‰~1.32‰,水体氮主要来源于含氮肥料、土壤侵蚀造成的有机氮输入以及人畜排泄物和城市生活污水输入.研究显示,近15年来松花江流域干流水体氮污染情况呈好转趋势,但重要支流水体氮污染仍严重,城市污染排放是流域水体氮污染的重要影响因素之一,需要加强对城市生活污水及化肥和粪肥等农业面源输入的管控. 展开更多
关键词 松花江 NH 4+-N TN 同位素 源解析
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Fingerprinting hydrothermal fluids in porphyry Cu deposits using K and Mg isotopes 认领
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作者 Weiqiang LI Shugao ZHAO +4 位作者 Xiaomin WANG Shilei LI Guoguang WANG Tao YANG Zhangdong JIN 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2020年第1期108-120,共13页
In this study, we performed an integrated investigation of K and Mg isotopes in hydrothermally altered rocks from the giant Dexing porphyry Cu deposit in China. Both the altered porphyry intrusion and the surrounding ... In this study, we performed an integrated investigation of K and Mg isotopes in hydrothermally altered rocks from the giant Dexing porphyry Cu deposit in China. Both the altered porphyry intrusion and the surrounding wall rocks exhibit large variations in K and Mg isotope compositions, with δ41K values ranging between-1.02‰ and 0.38‰, and δ26Mg values ranging between-0.49‰ and 0.32‰. The δ41K and δ26Mg values of the majority of altered samples are higher than the isotopic baseline values for upper continental crust. We attribute the general increase in δ41 K and δ26Mg in altered rocks to hydrothermal alteration,which caused preferential incorporation of heavy K and Mg isotopes in alteration products, particularly phyllosilicates. However,a few altered samples show anomalously low δ41K and δ26Mg values. The δ41K and δ26Mg values do not correlate with K and Mg concentrations, or mineralogy of altered samples. The variable K-Mg isotope data likely reflect fluids of different physicalchemical properties, or different isotopic compositions. Based on the combined K-Mg isotope data, at least three groups of hydrothermal fluids are distinguished from the Dexing porphyry deposit. Therefore, K-Mg isotopes are potentially a novel tracer for fingerprinting fluids in complex hydrothermal systems. 展开更多
关键词 HYDROTHERMAL ISOTOPE ALTERATION
Dissipation of S-metolachlor and butachlor in agricultural soils and responses of bacterial communities:Insights from compound-specific isotope and biomolecular analyses 认领
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作者 Ehssan Torabi Charline Wiegert +2 位作者 Benoit Guyot Stéphane Vuilleumier Gwenael Imfeld 《环境科学学报:英文版》 SCIE EI CAS CSCD 2020年第6期163-175,共13页
The soil dissipation of the widely used herbicides S-metolachlor(SM)and butachlor(BUT)was evaluated in laboratory microcosms at two environmentally relevant doses(15 and 150μg/g)and for two agricultural soils(crop an... The soil dissipation of the widely used herbicides S-metolachlor(SM)and butachlor(BUT)was evaluated in laboratory microcosms at two environmentally relevant doses(15 and 150μg/g)and for two agricultural soils(crop and paddy).Over 80%of SM and BUT were dissipated within 60 and 30 days,respectively,except in experiments with crop soil at 150μg/g.Based on compound-specific isotope analysis(CSIA)and observed dissipation,biodegradation was the main process responsible for the observed decrease of SM and BUT in the paddy soil.For SM,biodegradation dominated over other dissipation processes,with changes of carbon isotope ratios(Δδ13C)of up to 6.5‰after 60 days,and concomitant production of ethane sulfonic acid(ESA)and oxanilic acid(OXA)transformation products.In crop soil experiments,biodegradation of SM occurred to a lesser extent than in paddy soil,and sorption was the main driver of apparent BUT dissipation.Sequencing of the 16 S rRNA gene showed that soil type and duration of herbicide exposure were the main determinants of bacterial community variation.In contrast,herbicide identity and spiking dose had no significant effect.In paddy soil experiments,a high(4:1,V/V)ESA to OXA ratio for SM was observed,and phylotypes assigned to anaerobic Clostridiales and sulfur reducers such as Desulfuromonadales and Syntrophobacterales were dominant for both herbicides.Crop soil microcosms,in contrast,were associated with a reverse,low(1:3,V/V)ratio of ESA to OXA for SM,and Alphaproteobacteria,Actinobacteria,and Bacillales dominated regardless of the herbicide.Our results emphasize the variability in the extent and modes of SM and BUT dissipation in agricultural soils,and in associated changes in bacterial communities. 展开更多
关键词 Chloroacetanilide herbicides Carbon isotope fractionation Pesticide degradation Bacterial diversity
Application of ^15N Stable Isotope Labeling Technology in Sugarcane Nitrogen Research 认领
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作者 Yiyun GUI Jinju WEI +5 位作者 Lianying MAO Haibi LI Ronghua ZHANG Hui ZHOU Rongzhong YANG Xihui LIU 《农业生物技术:英文版》 CAS 2020年第3期100-103,共4页
Nitrogen is one of the essential nutrient elements for plant growth,which plays an important role in the growth and development of sugarcane. The whole growth cycle of sugarcane needs a large amount of nitrogen. Incre... Nitrogen is one of the essential nutrient elements for plant growth,which plays an important role in the growth and development of sugarcane. The whole growth cycle of sugarcane needs a large amount of nitrogen. Increasing the application of nitrogen can improve the yield of sugarcane,but it will also cause environmental pollution. Therefore,how to control or reduce the application of nitrogen fertilizer while continuously increasing sugarcane yield,reduce the increase of sugarcane production cost and environmental pollution caused by excessive application of nitrogen fertilizer has become an important scientific problem faced by sugarcane industry in China.^15N stable isotope labeling technology has been applied to many crops as a nitrogen research tool. In order to better understand the demand of nitrogen fertilizer in soil-cane system,this paper reviewed nitrogen allocation in plants,nitrogen loss,nitrogen recycling and endogenous nitrogen fixation of sugarcane based on^15N stable isotope labeling technology used in the nitrogen uptake and utilization,providing a theoretical basis for the improvement of sugarcane nitrogen use efficiency and the efficient nitrogen fertilizer management of sugarcane. 展开更多
关键词 NITROGEN SUGARCANE ^15N stable isotope Utilization efficiency
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Evidence for niche differentiation of nitrifying communities in grassland soils after 44 years of different field fertilization scenarios 认领
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作者 Zhongjun JIA Xue ZHOU +6 位作者 Weiwei XIA Dario FORNARA Baozhan WANG Elizabeth Anne WASSON Peter CHRISTIE Martin F.POLZ David D.MYROLD 《土壤圈:英文版》 SCIE CAS CSCD 2020年第1期87-97,共11页
Long-term nitrogen(N)fertilization imposes strong selection on nitrifying communities in agricultural soil,but how a progressively changing niche affects potentially active nitrifiers in the field remains poorly under... Long-term nitrogen(N)fertilization imposes strong selection on nitrifying communities in agricultural soil,but how a progressively changing niche affects potentially active nitrifiers in the field remains poorly understood.Using a 44-year grassland fertilization experiment,we investigated community shifts of active nitrifiers by DNA-based stable isotope probing(SIP)of field soils that received no fertilization(CK),high levels of organic cattle manure(HC),and chemical N fertilization(CF).Incubation of DNA-SIP microcosms showed significant nitrification activities in CF and HC soils,whereas no activity occurred in CK soils.The 44 years of inorganic N fertilization selected only 13C-ammonia-oxidizing bacteria(AOB),whereas cattle slurry applications created a niche in which both ammonia-oxidizing archaea(AOA)and AOB could be actively13C-labeled.Phylogenetic analysis indicated that Nitrosospira sp.62-like AOB dominated inorganically fertilized CF soils,while Nitrosospira sp.41-like AOB were abundant in organically fertilized HC soils.The 13C-AOA in HC soils were affiliated with the 29i4 lineage.The 13C-nitrite-oxidizing bacteria(NOB)were dominated by both Nitrospira-and Nitrobacter-like communities in CF soils,and the latter was overwhelmingly abundant in HC soils.The 13C-labeled nitrifying communities in SIP microcosms of CF and HC soils were largely similar to those predominant under field conditions.These results provide direct evidence for a strong selection of distinctly active nitrifiers after 44 years of different fertilization regimes in the field.Our findings imply that niche differentiation of nitrifying communities could be assessed as a net result of microbial adaption over 44 years to inorganic and organic N fertilization in the field,where distinct nitrifiers have been shaped by intensified anthropogenic N input. 展开更多
关键词 ammonia-oxidizing ARCHAEA ammonia-oxidizing BACTERIA community shift long-term FERTILIZATION nitrite-oxidizing BACTERIA nitrogen enrichment stable isotope probing MICROCOSM
Stable Isotope Signatures and Moisture Transport of a Typical Heavy Precipitation Case in the Southern Tianshan Mountains 认领
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作者 WANG Liwei ZHANG Mingjun +5 位作者 WANG Shengjie Athanassios AARGIRIOU WANG Gaofei Vasileios SALAMALIKIS SHI Mengyu JIAO Rong 《中国地理科学:英文版》 SCIE CSCD 2020年第1期180-188,共9页
Stable oxygen isotopes in precipitation contain meaningful environmental information on a synoptic scale and can be applied to diagnose hydrometeorological processes.A series of rainstorms occurred at the southern Tia... Stable oxygen isotopes in precipitation contain meaningful environmental information on a synoptic scale and can be applied to diagnose hydrometeorological processes.A series of rainstorms occurred at the southern Tianshan Mountains during the period from May to June 2013,and the event-based precipitation was sampled along the mountain range from west to east.Based on δ18 O values in precipitation samples as well as the corresponding meteorological parameters,the moisture transport paths during the sampling period were identified.In late-May(stage 1),isotopes in precipitation collected generally showed a depleting trend.In mid-June(stage 2),there was no coherent trend of isotopes in precipitation for these stations,and only isotope values in Aksu showed a continually depleting trend.Checking other meteorological proxies during the sampling period,the event-based precipitation isotopes sensitively reflected the moisture process.In central Asia,both the westerly and monsoon moisture can be delivered to cause extreme precipitation events,and the isotopic information provides an alternative tool to investigate the atmospheric processes. 展开更多
关键词 precipitation stable ISOTOPE moisture source TIANSHAN MOUNTAINS
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利用水同位素和水文地球化学证据表征张家口地区的地下水年龄和补给率 认领
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作者 张清华 罗专溪 +3 位作者 陆文 HARALD Zepp 赵玉峰 唐家良 《地理学报:英文版》 SCIE CSCD 2020年第6期935-948,共14页
Despite the increasing depletion of the groundwater at the Zhangjiakou aquifer system in the northwest of Beijing-Tianjin-Hebei region,little information is available on the hydrological process of groundwater in this... Despite the increasing depletion of the groundwater at the Zhangjiakou aquifer system in the northwest of Beijing-Tianjin-Hebei region,little information is available on the hydrological process of groundwater in this region.In this study,we utilized water isotopes composition(51sO,5D and 3H)of groundwater,river and precipitation to identify the characteristics of hydrochemistry,groundwater age and recharge rates in different watersheds of the Zhangjiakou area.Results showed that the river water and groundwater could be characterized as HCO3-Mg Na,HCO3 CI-Na and HCO3-Mg Na,HCO3 CI-Na,HCO3 CI-Na Mg types,respectively.The 5D and 5180 values in precipitation were linearly correlated,which is similar to the Global Meteorological Water Line(GMWL).Furthermore,the decreasing values of the 6D and 5180 from precipitation to surface water and groundwater indicate that groundwater is mainly recharged by atmospheric precipitation.In addition,the variation of 3H concentration with depth suggests that groundwater shallower than around 100 m is generally modern water.In contrast,groundwater deeper around 100 m is a mixture of modern and old waters,which has longer residence times.Groundwater showed a relatively low tritium concentration in the confined aquifers,indicating the groundwater recharged might be relatively old groundwater of over 60 years.The flow velocity of the groundwater in the study area varied from 1.10 to 2.26 m/a,and the recharge rates ranged from 0.034 to 0.203 m/a.The obtained findings provide important insights into understanding the groundwater recharge sources and hydrochemistry in the Zhangjiakou area,in turn developing a sustainable groundwater management plan. 展开更多
关键词 hydrogen and oxygen isotopes tritium isotope water cycle GROUNDWATER Zhangjiakou
黑龙江省塔源二支线铅锌多金属矿床硫同位素研究 认领
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作者 周子高 赵亮 +1 位作者 李星 王道会 《云南冶金》 2020年第1期1-5,共5页
大兴安岭地区由于其处于重要的古生代古亚洲洋构造-成矿域与中生代滨西太平洋构造-成矿域强烈叠加复合部位,因此是中国最重要的有色金属成矿区域之一。此研究开展了塔源矿床硫同位素测试,硫是这些成矿金属元素沉淀的重要矿化剂,因而通... 大兴安岭地区由于其处于重要的古生代古亚洲洋构造-成矿域与中生代滨西太平洋构造-成矿域强烈叠加复合部位,因此是中国最重要的有色金属成矿区域之一。此研究开展了塔源矿床硫同位素测试,硫是这些成矿金属元素沉淀的重要矿化剂,因而通常利用硫同位素能间接示踪矿物成矿物质的来源。 展开更多
关键词 黑龙江 塔源 S同位素
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Use of breakthrough experiment to evaluate the performance of hydrogen isotope separation for metal-organic frameworks M-MOF-74(M=Co, Ni, Mg, Zn) 认领
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作者 Yanan Si Wenjing Wang +1 位作者 El-Sayed M.El-Sayed Daqiang Yuan 《中国科学:化学英文版》 SCIE EI CAS CSCD 2020年第7期881-889,共9页
The unique adsorption performance of metal-organic frameworks(MOFs) indicates a new direction for gas separation and purification. The low-temperature distillation, as a traditional technique for hydrogen isotope sepa... The unique adsorption performance of metal-organic frameworks(MOFs) indicates a new direction for gas separation and purification. The low-temperature distillation, as a traditional technique for hydrogen isotope separation, is limited as it is a high energy-and cost-intensive process. Instead of utilizing such a conventional separation route, we use ordered microporous frameworks based on a physical adsorption mechanism to solve the challenge of hydrogen isotope separation. Herein we analyze M-MOF-74(M=Co, Ni, Mg, Zn), featuring a hexagonal channel about 11 ? and high density of open metal sites, for their ability to separate and purify deuterium from the hydrogen isotope mixture by dynamic column breakthrough experiments. Our results show that the combination of the strength of binding sites, density of coordinatively unsaturated metal sites and hydrogen isotope adsorption capacity of materials renders Co-MOF-74 as an optimal adsorbent for the capture of deuterium from hydrogen isotope mixtures in a simulated industrial process. 展开更多
关键词 hydrogen isotope SEPARATION breakthrough experiment MOF-74
甘肃塘坝金矿床成矿流体特征及矿床成因 认领
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作者 马塬皓 刘云华 +3 位作者 赵强 吴勇 李小严 邓楠 《黄金》 CAS 2020年第2期3-11,共9页
塘坝金矿床位于西秦岭金成矿带南部文县—康县金成矿亚带东段,为石英脉型金矿床。野外地质调查发现,矿体主要产于花岗斑岩脉附近的断裂中,在空间上与花岗斑岩脉关系密切,成矿作用可划分为3个阶段。流体包裹体显微测温结果表明:不同阶段... 塘坝金矿床位于西秦岭金成矿带南部文县—康县金成矿亚带东段,为石英脉型金矿床。野外地质调查发现,矿体主要产于花岗斑岩脉附近的断裂中,在空间上与花岗斑岩脉关系密切,成矿作用可划分为3个阶段。流体包裹体显微测温结果表明:不同阶段成矿流体包裹体类型相近,矿床成矿温度为156.9℃~303.2℃,盐度为1.82%~15.67%,密度为0.76~0.99 g/cm 3,深度为5.18~7.43 km;成矿流体具有中低温度、中低盐度、低密度、中浅成相特征。包裹体激光拉曼光谱分析显示,包裹体气相成分主要为CO 2、H 2O,含少量N 2,液相成分主要为H 2O,属于H 2O-NaCl±CO 2体系。氢-氧-硫同位素分析结果表明,塘坝金矿床δ18 O H 2O为5.98‰~9.87‰,δD V-SMOW为-80.6‰~-74.5‰,δ34 S为-1.9‰~8.0‰;结合矿床野外产出特征,成矿流体主要来源于岩浆热液。综合分析认为,该矿床为与岩浆作用有关的中低温度、中低盐度岩浆期后热液型金矿床。 展开更多
关键词 流体包裹体 成矿流体 同位素 矿床成因 塘坝金矿床
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O,H,and Sr isotope evidence for origin and mixing processes of the Gudui geothermal system,Himalayas,China 认领
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作者 Chenguang Wang Mianping Zheng +4 位作者 Xuefei Zhang Enyuan Xing Jiangyi Zhang Jianhong Ren Yuan Ling 《地学前缘:英文版》 SCIE CAS CSCD 2020年第4期1175-1187,共13页
Tho Gudui geothermal field records the highest temperature at equivalent borehole depths among the lainland hydrothermal systems in mainland China.Located about 150 km southeast of Lhasa City,the capital of Tibet,the ... Tho Gudui geothermal field records the highest temperature at equivalent borehole depths among the lainland hydrothermal systems in mainland China.Located about 150 km southeast of Lhasa City,the capital of Tibet,the Gudui geothermal field belongs to the Sangri-Cuona rift belt,also known as the Sangri-Cuona geothermal belt,and is representative of the non-volcanic geothermal systems in the Himalayas.In this study,oxygen-18 and deuterium isotope compositions as well as 87Sr/86Sr ratios of water samples collected from the Gudui geothermal field were characterized to understand the origin and mixing processes of the geothermal fluids at Gudui.Hydrogen and oxygen isotope plots show both,deep and shallow reservoirs in the Gudui geothermal field.Deep geothermal fluids are the mixing product of magmatic and infiltrating snow-melt water.Calculations show that the magma fluid component of the deep geothermal fluids account for about 21.10%-24.04%;magma fluids lay also be a contributing source of lithium.The linear relationship of the 87Sr/86Sr isotopic ratio versus the 1/Sr plot indicates that shallow geothermal fluids form from the mixing of deep geothermal fluids with cold groundwater.Using a binary mixing model with deep geothermal fluid and cold groundwater as two end-members,the nixing ratios of the latter in most surface hot springs samples were calculated to be between 5% and 10%.Combined with basic geological characteristics,hydrogen and oxygen isotope characteristics,strontium concentration,87Sr/(86)Sr ratios,and the binary mixing model,we infer the 6 th-Class Reservoirs Evolution Conceptual Model(6-CRECM) for the Gudui geothermal system.This model represents an idealized summary of the characteristics of the Gudui geothermal field based on our comprehensive understanding of the origin and mixing processes of the geothermal fluid in Gudui.This study may aid in identifying the geothermal and geochemical origin of the Gudui high-temperature hydrothermal systems in remote Tibet of China,whose potential for geotherma 展开更多
关键词 Geothermal fluid Oxygen-18 and deuterium isotope 87Sr/86Sr ratio Origin and mixing Gudui HIMALAYAS
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