检索结果-南通市图书馆

Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,china

引用

Science china Earth Sciences 2006年第1期49卷 77-87页

作者： ma jinlong1,2, tao mingxin2,3.& ye xianren2 1. resources and environmental school, lanzhou university, lanzhou 73.000, china 2. Key Laboratory of Gas Geochemistry, Institute of Geology and Geophysics, Chinese Academy of Sciences, lanzhou 73.000, china 3. College of resources Science & Technology, Beijing Normal university, Beijing 100875, china resources and {1. school Lanzhou University Lanzhou China Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou China College of resources Science & Technology Beijing Normal University Beijing China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, china, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2, CO and H_2, which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternchina; ratios of ~3He/~4He in almost all samples range from 0.82 Ra to 2.74 Ra, whereas^(40)Ar/^(36)Ar from 299.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3He range from 27.6 x 1.~9 to 1.50 x 1.~9,N_2/Ar from 927 to 5661., and N_2/~3He from 2.5 x 1.~9 to 27 x 1.~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

TEMPORAL AND SPATIAL DISTRIBUTION OF PHOSPHORUS IN THE XIANGXI RIVER

引用

水生生物学报 2006年第6期30卷 647-651页

作者： FU Chang-Ying 1.2, FANG tao 1. DENG Nan-Sheng 2and YU Hai-Qiao 1.3 (1. Institute of Hydrobiology,the Chinese Academy of Sciences, Wuhan 430072,{1. 2. school of environmental Sciences and resources,Wuhan university, Wuhan 430079 3. school of resources and environmental Engineering, Wuhan university of Technology, Wuhan 430070) Institute of Hydrobiology the Chinese Academy of Sciences Wuhan 430072 school of {1. Sciences and resources Wuhan University Wuhan 430079

The phosphorus in water and sediment collected at different time from the Xiangxi River were analyzed. The results indicated that the phosphorus pollution have significant relations to human activities (especially the phosphorus industry). The concentrations of total-phosphorus (TP), total dissolved phosphorus (TDP) and dissolved phosphorus (DP) in Dec.2004 were higher than those in Jul. 2005; the TP contents of sites 1. and 1. were much higher than others’, the TP content of the largest site 1. was 1.46.29mg/kg in Dec. 2004 and 1.56.1.mg/kg in Jul. 2005, respectively, which was much higher than the average (1.97.51.g/kg and 1.69.38mg/kg, respectively). The TP content in the sediment of the Xiangxi River was from 1.79.53mg/kg to 1.51.20mg/kg. The TP contents of most sites except site 1., 1. and 20 were higher in Dec. 2004 than those in Jul. 2005. The aluminium-phosphorus (Al-P) content in the sediment was obviously higher in Jul. 2005 than that in Dec.2004, which indicated that the stability of Al-P has a significant relation to the change of season.

关键词： Phosphorus Sediment Adsorption and release Xiangxi River Three Gorges

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Prestoring lithium into SnO_(2)coated 3D carbon fiber cloth framework as dendrite-free lithium metal anode

引用

Particuology 2024年第1期84卷 89-97页

作者： tao Wei Yanyan Zhou Cheng Sun Lesheng Liu Sijia Wang Mengting Wang {1. Liu Qing Huang Quanchao Zhuang Yongfu Tang school of Energy and Power Jiangsu University of Science and TechnologyZhenjiang212003China College of materials Science and Engineering Nanjing Forestry UniversityNanjing210037China Li-ion Batteries Lab School of Materials Science and EngineeringChina University of Mining and TechnologyXuzhouChina Hebei Key Laboratory of Applied Chemistry School of Environmental and Chemical EngineeringYanshan UniversityQinhuangdao066004China

For several decades,the promise of implementing of lithium(Li)metal anodes has been regarded as the"holy grail"for Li-based ***,we have proposed a facile design of a carbon fiber cloth(CFC)framework coated with SnO_(2)nanoparticles through a hydrothermal process,which served as a reliable host for prestoring molten Li to produce a CFC@SnO_(2)@Li composite ***,TEM,HRTEM,XPS and different electrochemical characterizations were carried *** to the synergetic effects of the 3D conductive CFC and the coated lithiophilic SnO_(2)nanoparticles,the designed CFC@SnO_(2)@Li electrodes can buffer the volume changes and reduce the local current density,thus suppress the Li dendrites during ***,the CFC@SnO_(2)electrodes showed a high and stable CE of 98.6%for 1.00 cycles at a current density of 1.ma cm^(-2)(1.mah cm^(-2)).What is more,at a high current density of 5 ma cm^(-2)and a high areal capacity of 5 mah cm^(-2),the symmetric cell displayed relatively low overpotential and long cycling lifetime of 1.00 *** results confirm its great potential as lithium metal anodes in practical battery applications.

关键词： Lithiophilic Lithium metal anodes SnO_(2) 3D anode Dendrite-free

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Simulating the transfer and fate of hexachlorocyclohexane in recent 50 years in Beijing,{1.

引用

Science china Earth Sciences 2005年第12期48卷 2203-2213页

作者： CAO Hongying1. LIANG tao1.& tao Shu2 1. Institute of Geographical Sciences and Natural resources Research, Chinese Academy of Sciences, Beijing 1.01.1. china 2. Laboratory for Earth Surface Processes, Peking university, Beijing 1.0871. china Institute of Geographical Sciences and Natural resources Research Chinese Academy of Sciences Beijing China Laboratory for Earth Surface Processes Peking University Beijing China

Taking Beijing as a study area, a dynamic fugacity model was used to simulate the transfer and fate of technical HCHs according to the physic-chemical properties of the studying environment and HCH isomers. Dynamic changes of the transfer fluxes and concentrations of HCH isomers during 1.52―2003 were simulated and the model results suggest good agreement between the calculated and measured concentrations of HCH isomers. During 1.52―1.83, the average input and output amount of HCHs through agricultural application and degradation are 1.0 t and 1.0 t respectively. The dominant transfer processes of HCHs in the study area are air-soil deposition, soil erosion and soil-air diffusion, transfer fluxes of these processes are 80 t?a?1. 1. t?a?1.and 1. t?a?1. which account for 92% of total transfer fluxes of HCHs isomers. There were approximately 253t HCHs in all {1. compartments of the study area during this period and 97% of which existed in soil compartment. Air and water advection became the dominant input sources of HCHs after 1.84 when the application of technical HCHs was prohib-ited, concentration of HCHs quickly descended to a quite low level in several years. Total amount of HCHs isomers remaining in the study area environment now is less than 5% that before 1.83, and this percentage may descend to 0.5% after 20 years by prediction.

关键词： fugacity model, hexachlorocyclohexane, compartment, transfer flux, fate.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The seismicity in the middle section of the Altyn Tagh Fault system revealed by a dense nodal seismic array

引用

Earthquake Research Advances 2024年第3期4卷 7-15页

作者： Shi Yao tao Xu Yingquan Sang Lingling {1. Tingwei Yang Chenglong Wu Minghui Zhang Key Laboratory of Mineral resources Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen518055China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing100029China university of Chinese Academy of Sciences Beijing100049China school of Infor{1.tion Engineering Shandong University of AeronauticsBinzhou256603China

The left-lateral Altyn Tagh Fault(ATF) system is the northern boundary of the Qinghai-Xizang Plateau, separating the Tarim Basin and the Qaidam Basin. The middle section of ATF has not recorded any large earthquakes since1.98 AD, so the potential seismic hazard is unclear. We develope an earthquake catalog using continuous waveform data recorded by the Tarim-Altyn-Qaidam dense nodal seismic array from September 1. to November23, 2021.in the middle section of ATF. With the machine learning-based picker, phase association, location, match and locate workflow, we detecte 233 earthquakes with M_L-1.3, far more than 6 earthquakes in the routine catalog. Combining with focal mechanism solutions and the local fault structure, we find that seismic events are clustered along the ATF with strike-slip focal mechanisms and on the southern secondary faults with thrusting focal mechanisms. This overall seismic activity in the middle section of the ATF might be due to the northeastward transpressional motion of the Qinghai-Xizang Plateau block at the western margin of the Qaidam Basin.

关键词： Altyn Tagh Fault machine learning Seismicity Dense seismic array

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Failure mechanisms and destruction characteristics of cemented coal gangue backfill under compression effect of non-uniform load

引用

Journal of Central South university 2024年第8期31卷 2676-2693页

作者： Feng, Guo-rui Guo, Wei Qi, Ting-ye Li, Zhu Cui, Jia-qing Wang, Hao-chen Cui, ye-kai ma, Jing-kai College of Mining Engineering Taiyuan University of Technology Taiyuan China Shanxi Province Research Center of Green Mining Engineering Technology Taiyuan China Shanxi Province Coal-based resources Green and High-efficiency Development Engineering Center Taiyuan China Shanxi Key Laboratory of Mine Rock Strata Control and Disaster Prevention Taiyuan China

Backfill mining is one of the most important technical means for controlling strata movement and reducing surface subsidence and environmental da{1.ge during exploitation of underground coal resources. Ensuring the stability of the backfill bodies is the pri{1.ry prerequisite for {1.intaining the safety of the backfilling working face, and the loading characteristics of backfill are closely related to the defor{1.tion and subsidence of the roof. Elastic thin plate model was used to explore the non-uniform subsidence law of the roof, and then the non-uniform distribution characteristics of backfill bodies’ load were revealed. Through a self-developed non-uniform loading device combined with acoustic emission (AE) and digital i{1.ge correlation (DIC) monitoring technology, the synergistic dynamic evolution law of the bearing capacity, apparent crack, and internal fracture of cemented coal gangue backfills (CCGBs) under loads with different degrees of non-uniformity was deeply explored. The results showed that: 1. The uniaxial compressive strength (UCS) of CCGB increased and then decreased with an increase in the degree of non-uniformity of load (DNL). About 40% of DNL was the inflection point of DNL-UCS curve and when DNL exceeded 40%, the strength decreased in a cliff-like {1.nner; 2) A positive correlation was observed between the AE ringing count and UCS during the loading process of the specimen, which was {1.nifested by a higher AE ringing count of the high-strength specimen. 3) Shear cracks gradually increased and failure mode of specimens gradually changed from “X” type dominated by tension cracks to inverted “Y” type dominated by shear cracks with an increase in DNL, and the crack opening displacement at the peak stress decreased and then increased. The crack opening displacement at 40% of the DNL was the s{1.llest. This was consistent with the judgment of crack size based on the AE b-value, i.e., it showed the typical characteristics of “s{1.ll b-value-large crack and

关键词： cemented coal gangue backfill crack opening displacement degree of non-uniformity of load failure mode non-uniform load

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Assimilation of temperature and salinity using isotropic and anisotropic recursive filters in Tropic Pacific

引用

Acta Oceanologica Sinica 2011年第1期30卷 15-23页

作者： LIU ye ZHAO Yanling National marine {1. Forecasting Center Beijing 100081 China No 61.41.Army Troop Beijing 10081 China

A data assimilation scheme used in the updated Ocean three-dimensional Variational Assimila- tion System （OVALS）, OVALS2, is described. Based on a recursive filter （RF） to estimate the background error covariance （BEC） over a predetermined scale, this new analysis system can be implemented with anisotropic and isotropic BECs. Similarities and differences of these two BEC schemes are briefly discussed and their impacts on the model simulation are also investigated. An idealized experiment demonstrates the ability of the updated analysis system to construct different BECs. Furthermore, a set of three {1.ars experiments is implemented by assimilating expendable bathythermograph （XBT） and ARGO data into a Tropical Pacific circulation model. The tao and WOA01.data are used to validate the assimilation results. The results show that the model simu- lations are substantially improved by OVALS2. The inter-comparison of isotropic and anisotropic BEC shows that the corresponding temperature and salinity produced by the anisotropic BEC are almost as good as those obtained by the isotropic one. Moreover, the result of anisotropic RF is slightly closer to WOA01.and tao than that of isotropic RF in some special area （e.g. the cold tongue area in the Tropic Pacific）.

关键词： recursive filter anisotropic isotropic background error covariance

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Response of Stream Pollution Characteristics to Catchment Land Cover in Cao-E River Basin, china

引用

Pedosphere 2011年第1期21卷 115-123页

作者： SHEN ye-Na LUE Jun CHEN Ding-Jiang SHI Yi-Ming Department of Natural resources College of Environmental Science and Natural Resources Zhejiang University Hangzhou 310029 (China) china Ministry of Education Key Lab of {1. Remediation and Ecological Health Zhejiang University Hangzhou 310029 (China) Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition Zhejiang University Hangzhou 310029 (China)

This study addressed the relationship of river water pollution characteristics to land covers and human activities in the catchments in a complete river system named Cao-E River in eastern *** on the hydrogeochemical data collected monthly over a period of 3 {1.ars,cluster analysis(CA) and principal component analysis(PCA) were adopted to categorize the river reaches and reveal their pollution *** to the differences of water quality in the river reaches and land use patterns and average population densities in their catchments,the whole river system could be categorized into three groups of river reaches,i.e.,non-point sources pollution reaches(NPSPR),urban reaches(UR) and mixed sources pollution reaches(MSPR).In UR and MSPR,the water quality was mainly impacted by nutrient and organic pollution,while in NPSPR nutrient pollution was the main *** nitrate was the main nitrogen form in NPSPR and particulate phosphorus was the main phosphorus form in *** were no apparent trends for the variations of pollutant concentrations with increasing river flows in NPSPR and MSPR,while in UR the pollutant concentrations decreased with increasing river *** dry season was the critical period for water pollution control in ***,catchment land covers and human activities had significant impact on river reach water pollution type,nutrient forms and water quality responses to hydrological conditions,which might be crucial for developing strategies to combat water pollution in watershed scale.

关键词： cluster analysis hydrological conditions pollution factors principle component analysis water quality

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effects of Amino Acids Replacing Nitrate on Growth,Nitrate Accumulation,and macroelement Concentrations in Pak-choi (Brassica chinensis L.)

引用

Pedosphere 2007年第5期17卷 595-600页

作者： WANG Hua-Jing WU Liang-Huan WANG Min-Yan ZHU Yuan-Hong tao Qin-Nan ZHANG Fu-Suo Ministry of Education Key Laboratory of environmental Remediation and Ecosystem Health College of Environmental and Resource Sciences Zhejiang University Hangzhou 310029 （China） College of Geography and Resource Sciences Sichuan Normal University Chengdu 610066 （China） Department of Crop and Soil Sciences the Pennsylvania State University （USA） College of resources and Environment China Agricultural University Beijing 100094 （China）

A hydroponic experiment was carried out to determine the influence of replacing 20% of nitrate-N in nutrient solutions with 20 individual amino acids on growth, nitrate accumulation, and concentrations of nitrogen （N）, phosphorus （P）, and potassium （K） in pak-choi （Brassica chinensis L.） shoots. When 20% of nitrate-N was replaced with arginine （Arg） compared to the full nitrate treatment, pak-choi shoot fresh and dry weights increased significantly （P ≤ 0.05）, but when 20% of nitrate-N was replaced with alanine （Ala）, valine （Val）, leucine （Leu）, isoleucine （Ile）, proline （Pro）, phenylalanine （Phe）, methionine （Met）, aspartic acid （Asp）, glutamic acid （Glu）, lysine （Lys）, glycine （Gly）, serine （Ser）, threonine （Thr）, cysteine （Cys）, and tyrosine （Tyr）, shoot fresh and dry weights decreased significantly （P ≤ 0.05）. After replacing 20% of nitrate-N with asparagine （Asn） and glutamine （Gin）, shoot fresh and dry weights were unaffected. Compared to the full nitrate treatment, amino acid replacement treatments, except for Cys, Gly, histidine （His）, and Arg, significantly reduced （P ≤0.05） nitrate concentrations in plant shoots. Except for Cys, Leu, Pro, and Met, total N concentrations in plant tissues of the other amino acid treatments significantly increased （P ≤ 0.05）. Amino acids also affected total P and K concentrations, but the effects differed depending on individual amino acids. To improve pak-choi shoot quality, Gln and Asn, due to their insignificant effects on pak-choi growth, their significant reduction in nitrate concentrations, and their increase in macroelement content in plants, may be used to partially replace nitrate-N.

关键词： amino acids growth N P and K nitrate accumulation pak-choi

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Absorption of Glycine by Three Agricultural Species Under Sterile Sand Culture Conditions

引用

Pedosphere 2005年第3期15卷 286-292页

作者： WULiang-Huan MOLiang-Yu FANZhi-Lian taoQin-Nan ZHANGFu-Suo MOEKeyLabofenvironmentalRemediationandEcosystemHealth CollegeofEnvironmentalandResourceSciencesZhejiangUniversityHangzhou310029（China） CollegeofresourcesandEnvironment ChinaAgriculturalUniversityBeijing100094（China）

Seedlings of wheat (Triticum aestivum L.), Chinese cabbage (Brassica campestris L.) and mung bean (Phaseolus radiatus L.) were grown for 30 days in sterile sand media with 6 N treatments, i.e. NH4+-N, glycine-N, 3 different ratios of glycine-N:NH4+-N (NH4+-N was labeled with 1.N) and a control receiving no N, to assess the importance of amino acids in excessive N nutrition along with inorganic N interactions. The contribution of nitrogen derived from glycine-N to total plant N was investigated. The total plant N of the three species treated with N was significantly greater (P < 0.05) than the control treatment. Also, seedlings from all the three species had significantly more total N as NH4+-N (P < 0.05) than at least two of the four treatments with glycine-N. However, for all species, differences in total N among treatments with a mixture of glycine-N and NH4+-N were mostly not significant. The contribution of N derived from glycine-N to plant total N content for all species increased with increasing glycine-N:NH4+-N ratio in the treatment solution. These results indicated that agricultural plants could effectively use organic nitrogen from organic nitrogen sources (e.g., glycine) and from organic and inorganic N mixtures (e.g., a glycine-N and NH4+-N mix). There were also genotypic differences in glycine-N and NH4+-N uptake by agricultural species.

关键词： Chinese cabbage (Brassica campestris L.) glycine-N mung bean (Phaseolus radiatus L.) NH4+-N wheat (Triticum aestivum L.)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：