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In-situ gas contents of a multi-section coal seam in Sydney basin for coal and gas outburst management
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作者 Zhongbei Li Ting Ren +4 位作者 Dennis Black Ming Qiao Itmam Abedin Jessica Juric Mike Wang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第4期34-46,共13页
The gas content is crucial for evaluating coal and gas outburst potential in underground coal mining. This study focuses on investigating the in-situ coal seam gas content and gas sorption capacity in a representative... The gas content is crucial for evaluating coal and gas outburst potential in underground coal mining. This study focuses on investigating the in-situ coal seam gas content and gas sorption capacity in a representative coal seam with multiple sections (A1, A2, and A3) in the Sydney basin, where the CO_(2) composition exceeds 90%. The fast direct desorption method and associated devices were described in detail and employed to measure the in-situ gas components (Q_(1), Q_(2), and Q_(3)) of the coal seam. The results show that in-situ total gas content (Q_(T)) ranges from 9.48 m^(3)/t for the A2 section to 14.80 m^(3)/t for the A3 section, surpassing the Level 2 outburst threshold limit value, thereby necessitating gas drainage measures. Among the gas components, Q_(2) demonstrates the highest contribution to Q_(T), ranging between 55% and 70%. Furthermore, high-pressure isothermal gas sorption experiments were conducted on coal samples from each seam section to explore their gas sorption capacity. The Langmuir model accurately characterizes CO_(2) sorption behavior, with ft coefcients (R^(2)) greater than 0.99. Strong positive correlations are observed between in-situ gas content and Langmuir volume, as well as between residual gas content (Q_(3)) and sorption hysteresis. Notably, the A3 seam section is proved to have a higher outburst propensity due to its higher Q_(1) and Q_(2) gas contents, lower sorption hysteresis, and reduced coal toughness f value. The insights derived from the study can contribute to the development of efective gas management strategies and enhance the safety and efciency of coal mining operations. 展开更多
关键词 in-situ coal seam gas content Direct desorption method Gas component Sorption capacity Coal and gas outburst
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Available Contents of Trace Nutrient Element and Factors Affecting Their Availability in Western Jilin 被引量:4
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作者 施宪 王冬艳 +2 位作者 李月芬 靳克 郭珍 《Agricultural Science & Technology》 CAS 2010年第5期73-76,共4页
Based on the assay of the total content and available content of the trace nutrient elements and the soil pH and organic matter of the soil samples,the characteristic of the available content of the trace nutrient ele... Based on the assay of the total content and available content of the trace nutrient elements and the soil pH and organic matter of the soil samples,the characteristic of the available content of the trace nutrient elements and their affecting factors are studied. The results show that the available B in western Jilin is in a middle level,the content in Nong'an is higher than that in the others; the available Mn is extremely abundant; the available Cu in Nong'an is obviously higher than other areas,and the content in Da'an differs greatly; the available Zn is in a middle level; the severe shortage of available Mo differs between different areas; and the available Fe is extremely abundant. The available Mn,Cu and Fe have significantly positive correlation with their total content; the available B has significantly positive correlation with pH,and Zn has obviously negative correlation with pH; the available Mn and Fe had significantly positive correlation with soil organic matter. 展开更多
关键词 Trace nutrient element Available content The affecting factors Western Jilin
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Correlation Between Chemical Element Contents in Tree Rings and Soils 被引量:8
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作者 QIANJUN-LONG KESHAN-ZHE 《Pedosphere》 SCIE CAS CSCD 1993年第4期309-319,共11页
The annual growth rings of ten trees and the soils near the tree roots were sampled from the mining area of lead-and zinc-dominant metals in the Xixia Mountain, Nanjing, for the determination of chemical element conte... The annual growth rings of ten trees and the soils near the tree roots were sampled from the mining area of lead-and zinc-dominant metals in the Xixia Mountain, Nanjing, for the determination of chemical element contents. The study results showed that the elemental contents in the tree rings were correlated with those in the soils, i. e., the elemental contents in the tree rings increased with those in the soils, even in the cases of different environments and different tree species. Therefore, a time-concentration sequence could be set up on the basis of determining the elemental contents in the successive annual growth rings of trees to qualitatively reflect the annual variations of relevant elements in the soils, and a time-concentration sequence of elemental contents in soils could also be established in terms of related model to reproduce the dynamic changes of the surroundings. 展开更多
关键词 CORRELATION elemental contents SOILS tree rings
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Carbon,Nitrogen,and Sulfur Contents in Marine Phytoplankton Cells and Biomass Conversion
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作者 CHEN Wenqing YANG Shimin +1 位作者 SHANG Jie WANG Jinwen 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第3期851-862,共12页
In this study,we isolated and cultured phytoplankton along the coast of China and measured the cellular carbon,nitrogen,and sulfur contents under four temperatures.The results showed that the contents of the cellular ... In this study,we isolated and cultured phytoplankton along the coast of China and measured the cellular carbon,nitrogen,and sulfur contents under four temperatures.The results showed that the contents of the cellular elements varied widely among different phytoplankton.We found that temperature is one of the important factors affecting the carbon,nitrogen,and sulfur contents in phytoplankton cells;however,the degree of influence of temperature is different for different kinds of phytoplankton.By measuring the nitrogen content in cells,we found that the C:N ratio indirectly measured in the experiment fluctuated in the range of 3.50-8.97,and the average C:N ratio was 5.52.In this experiment,we accurately measured the cell elemental contents at different temperatures and transformed the cell count results into carbon,nitrogen,and sulfur contents to express the biomass.This method ensures that the contribution of species that are small in number but with a large cell volume in biomass is considered.Moreover,this method comprehensively considers the interspecific differences of species and the uneven distribution of elements in phytoplankton cells,which is of significance in the estimation of marine carbon and nitrogen budget.The distribution of nitrogen content in marine phytoplankton can well indicate the marine eutrophication caused by human activities.Climate change can affect the community structure and element composition of marine phytoplankton,meanwhile marine carbon and nitrogen element can regulate the climate to a certain extent. 展开更多
关键词 PHYTOPLANKTON temperature gradient carbon element nitrogen element sulfur element element content distribution
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Chrono-Sequences of Elemental Contents in Tree Ringsand Soils 被引量:3
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作者 QIANJUN-LONG KESHAN-ZHE 《Pedosphere》 SCIE CAS CSCD 1994年第1期27-33,共7页
There exists a logarithmic linear correlation, i. e., In C'(Z, t) = a(Z) + b(Z) ln(Z, t) where Z is the atomicnumber of element and t the year when tree ring grows between the chemical element contents in tree rin... There exists a logarithmic linear correlation, i. e., In C'(Z, t) = a(Z) + b(Z) ln(Z, t) where Z is the atomicnumber of element and t the year when tree ring grows between the chemical element contents in tree ringsC(Z, t) and those in the soils near the tree roots C'(Z, t).By determining the elemental contents of the annual growth rings of trees, we could establish the chrono-sequences of elemental contents in the tree rings, thus calculating that of the soil, that is, reproducing thedynamic changes of contents of elements in the soil C'(Z, t). The background values of elements in the soilunder site conditions of the tree could be estimated from the minimum C(Z, t_0) in the chrono-sequences ofelemental contents in the tree rings. 展开更多
关键词 background value chroncasequences elemental contents SOILS tree rings
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Angular Distribution of Element Contents in Tree Rings and the Environmental Information 被引量:2
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作者 KE SHANZHE LIU ZHENGRONG +1 位作者 QIAN JUNLONG CHEN RUSONGI and KE XIAOKANG (Physics Department, Nanjing University, Nanjing 210095,China)(Nanjing Institute of Geogmphy and Limnology, the Chinese Academy of Sciences, Nanjing 210008, China)(Garded and Greenbelt 《Pedosphere》 SCIE CAS CSCD 1999年第1期69-76,共8页
Element contents of tree rings and soils near tree roots collected from Deodar cedar (Cedrus deodara (Roxb.) G. Don) and Masson pine (Picks massoniana lamb.) were determined to study the relationship between the angul... Element contents of tree rings and soils near tree roots collected from Deodar cedar (Cedrus deodara (Roxb.) G. Don) and Masson pine (Picks massoniana lamb.) were determined to study the relationship between the angular distribution of element contents in tree rings and the environmental information. The chemical composition and properties of soils are very much complicated, which leads to the non-uniform distribution of the element contents in tree rings. The statistical multi-variable regression method was used to got the information of the tree-centered distribution of element contents in the environment (soil) (C’), C’(z, θj ), from the distribution of element contents in tree rings (C), C(Z, θi), which depends on the plane azimuth angle (θi), i. e., C=C(Z,θi), where Z is the atomic number of the element, with a satisfactory result,though this study is only a primary one. 展开更多
关键词 angular distribution element contents environmental information tree rings
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ELEMENTAL CONTENTS IN ORGANS AND TISSUES OF CHINESE ADULT MEN 被引量:1
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作者 Hong-da Zhu Jing-yu Wang +8 位作者 Quan Wu Nei-fen Wang Ti-jiang Fan Hu-sheng Liu Qing-fen Liu Xiao-yan Wang Li Ou-yang Ya-qiong Liu Qing Xie 《Chinese Medical Sciences Journal》 CAS CSCD 2007年第2期71-82,共12页
Objective To provide basis of reference values for relevant parameters of Chinese Reference Man. Methods Eighteen kinds of major organ or tissue samples, including muscle, rib, liver, and so on, were obtained from 4 a... Objective To provide basis of reference values for relevant parameters of Chinese Reference Man. Methods Eighteen kinds of major organ or tissue samples, including muscle, rib, liver, and so on, were obtained from 4 areas (Hebei, Shanxi, Jiangsu, and Sichuan provinces) with different dietary patterns in China in autopsy of 16 healthy adult men, who had just encountered sudden deaths. At the same time, whole blood samples were collected from 10 volunteers living in each of these areas. The concentrations of 56 elements in these samples were detected by using Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES), and Graphite Furnace Atomic Absorption Spectrometry (GF-AAS) techniques. Based on obtained concentrations and reference values of these organ or tissue weights for Chinese Reference Man, the relative elemental burdens in these organs or tissues as well whole body were also estimated. Results The concentrations of 56 elements in 18 main organs or tissues were determined all together and their elemental organ or tissue and whole body burdens were estimated. Furthermore, the distributions of important elements for radiation protection in these organs or tissues were emphatically discussed. Conclusion By summing with past related results, the total results obtained from the series of research may provide more reliable and better representative basis of these reference values for Chinese Reference Man than before. 展开更多
关键词 Chinese adult man elemental content ORGAN tissue whole body BURDEN
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Macro-and Microelement Contents of Fruiting Bodies of Wild-Edible Mushrooms Growing in the East Black Sea Region of Turkey 被引量:4
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作者 Faik A.Ayaz Hülya Torun +3 位作者 Ahmet Colak Ertugrul Sesli Mark Millson Robert H.Glew 《Food and Nutrition Sciences》 2011年第2期53-59,共7页
Eleven different wild-edible mushroom species growing in the Black Sea region of Turkey were analysed for their metal content. Specimens of mushrooms were gathered in Trabzon, Giresun and Ordu and analyzed for 31 mine... Eleven different wild-edible mushroom species growing in the Black Sea region of Turkey were analysed for their metal content. Specimens of mushrooms were gathered in Trabzon, Giresun and Ordu and analyzed for 31 minerals, four of which (Be, Sb, Te and Ti) were not detected. Whereas some minerals including Ag, As, Cd, La, Mo, Pb, Se, Y and Zr were detected in just a few mushroom species, another 18 minerals were found in all 11 species. All metal concentrations were expressed on a dry weight basis (d.w.). With regard to nutritionally important amounts of essential and trace minerals, the metal content (μg/g d.w.) of mushroom samples ranged from 21,800-39,800 for K, 2590-14,000 for P, 268-1600 for Ca, 561-1210 for Mg, 74-829 for Fe, 11.2-321 for Cu, 36.2-241 for Zn, 14.1-76.5 for Mn and 0.13-2.85 for Co. Small amounts of toxic metals such as As, Cd and Pb were found in all 11 mushroom species. L. laccata contained a large amount of As (145 μg/g d.w.). These results show that the investigated mushrooms can be a useful component for human diets because of their high content of many essential minerals and trace elements and low content of toxic metals. 展开更多
关键词 Wild-edible Mushrooms Mineral content Toxic Metals Trace elements TURKEY
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Genesis of the Jianbeigou Gold Deposit on the Southern Margin of the North China Craton: Insights from Fluid Inclusions, H-O-S Isotopes, and Pyrite in situ Trace Element Analyses
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作者 LI Fengchun ZENG Qingdong +5 位作者 ZHU Rixiang CHU Shaoxiong XIE Wei YU Bing WU Jinjian LI Xinghui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第4期969-991,共23页
The Jianbeigou gold deposit is a typical lode gold deposit in the Qinling metallogenic belt, located on the southern margin of the North China Craton. Three stages of the hydrothermal process can be distinguished, inc... The Jianbeigou gold deposit is a typical lode gold deposit in the Qinling metallogenic belt, located on the southern margin of the North China Craton. Three stages of the hydrothermal process can be distinguished, including the quartz ± pyrite, quartz-polymetallic sulfide, and quartz-carbonate ± pyrite stages. From the early to late stages, the homogenization temperatures of primary fluid inclusions are 281–362°C, 227–331°C, and 149–261°C, respectively. The corresponding salinities estimated for these fluids are 3.9–9.9 wt%, 0.4–9.4 wt%, and 0.7–7.2 wt% Na Cl equiv. Combined with laser Raman spectroscopy data, the ore-forming fluid belongs to a H_(2)O-CO_(2)-Na Cl ± CH_4 system with medium–low temperature and salinity. The δ~(18)Ofluid and δD values for the quartz veins are-1.0‰ to 6.0‰ and-105‰ to-84‰, respectively, which indicates that the ore-forming fluid is of mixed source, mainly derived from magma, with a contribution from meteoric water. Pyrite has been identified into three generations based on mineral paragenetic sequencing, including Py1, Py2, and Py3. The pyrites have δ~(34)S sulfur isotopic compositions from three stages between 3.7‰ and 8.4‰, indicating that sulfur mainly originated from magma. Te, Bi, Sb, and Cu contents in pyrite were all high and showed a strong correlation with Au concentrations. Native gold and the Au-Ag-Bi telluride minerals were formed concurrently, and the As concentration was low and decoupled from the Au content. Therefore, Te, Bi, Sb and other low-melting point chalcophile elements play an important role for gold mineralization in arsenic-deficient ore-forming fluid. Combined with the geological setting, evolution of pyrite, and ore-fluids geochemistry, we propose that the Jianbeigou deposit can be classified as a magmatic–hydrothermal lode gold deposit. Gold mineralization on the southern margin of the North China Craton is related to Early Cretaceous magmatism and formed in an extensional setting. 展开更多
关键词 ore genesis H-O-S isotopes fluid inclusions in-situ trace element Jianbeigou gold deposit
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In-situ Micro-CT analysis of deformation behavior in sandwich-structured meta-stable beta Ti−35Nb alloy
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作者 Yu-jing LIU Zi-lin ZHANG +4 位作者 Jin-cheng WANG Xiang WU Xiao-chun LIU Wei-ying HUANG Lai-chang ZHANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第8期2552-2562,共11页
Beta Ti−35Nb sandwich-structured composites with various reinforcing layers were designed and produced using additive manufacturing(AM)to achieve a balance between light weight and high strength.The impact of reinforc... Beta Ti−35Nb sandwich-structured composites with various reinforcing layers were designed and produced using additive manufacturing(AM)to achieve a balance between light weight and high strength.The impact of reinforcing layers on the compressive deformation behavior of porous composites was investigated through micro-computed tomography(Micro-CT)and finite element method(FEM)analyses.The results indicate that the addition of reinforcement layers to sandwich structures can significantly enhance the compressive yield strength and energy absorption capacity of porous metal structures;Micro-CT in-situ observation shows that the strain of the porous structure without the reinforcing layer is concentrated in the middle region,while the strain of the porous structure with the reinforcing layer is uniformly distributed;FEM analysis reveals that the reinforcing layers can alter stress distribution and reduce stress concentration,thereby promoting uniform deformation of the porous structure.The addition of reinforcing layer increases the compressive yield strength of sandwich-structured composite materials by 124%under the condition of limited reduction of porosity,and the yield strength increases from 4.6 to 10.3 MPa. 展开更多
关键词 beta titanium alloy sandwich-structured composite in-situ micro-computed tomography finite element modeling compressive behavior
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Contents of Trace Metal Elements in Cow Milk Impacted by Different Feedstuffs
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作者 Song Ren-ju Tong Hui-li +1 位作者 Huang Jian-guo Gao Xue-jun 《Journal of Northeast Agricultural University(English Edition)》 CAS 2015年第3期54-61,共8页
Feedstuff intake plays key role in impacting the yield and quality of milk. In this study, we discussed the contents of trace metal elements in cow milk impacted by different feedstuffs. We detected the contents of Pb... Feedstuff intake plays key role in impacting the yield and quality of milk. In this study, we discussed the contents of trace metal elements in cow milk impacted by different feedstuffs. We detected the contents of Pb, Cd, As, Cu, Mg, Ca, Fe and Zn in different feedstuffs and milk by atomic absorption spectrophotometry. The determinations of Pb, Cd and As contents were by graphite furnace A_AS and Cu, Mg, Ca, Fe and Zn was by flame atomic absorption spectrometry. The results showed that Pb, Cd, As and Cu presented in feedstuffs, but Pb, Cd and As were lowly detected in milk samples, and Cu was not detected in milk samples. The content of Mg in concentrates was lower than that in forages. However, the content of Mg in milk from concentrate feed was higher than that in forage feed. This suggested that the utilization of Mg in concentrate feed was higher than that in forage feed. The contents of Ca and Zn were opposite to Mg, and the utilization of Ca and Zn in forage feed was higher than that in concentrate feed. There was no obviously change law of Fe in different feedstuffs and milk samples. The relationship between the contents of trace metal elements in milk to feedstuffs would provide a theoretical basis for dairy farming. It would be useful for improving the milk yield and milk quality of dairy production. 展开更多
关键词 feedstuff cow milk trace metal element content
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Prediction of Chemical Element Contents in Soils
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作者 KESHAN-ZHE QIANJUN-LONG 《Pedosphere》 SCIE CAS CSCD 1994年第2期105-117,共13页
Assuming that the regularity for the dynamic changes of the chrono-sequences of chemical element contents intree rings follows a k-order constant coefficient differential equation and substituting the differential wit... Assuming that the regularity for the dynamic changes of the chrono-sequences of chemical element contents intree rings follows a k-order constant coefficient differential equation and substituting the differential with the differ-ence, we could obtain the inferred value y_(m+k+1) by the formula: Each coefficient c_i in the formula may be ascertained by use of the measured data in the chrono-sequences. Ex-tending the chrono-sequences on the assumption that the regularity of dynamic changes wouldn't change in the nearfuture, the contents of chemical elements in the soils may be predicted in termis of a logarithmic linear correlationmodel. Also, this extension method could be used for the reproduction of the contents of chemical elements in soilsduring different periods of time in the past. 展开更多
关键词 Chrono-sequences of elemental contents EXTENSION PREDICTION SOILS tree rings
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Comparison of 66 chemical element contents in normal and benign hyperplastic prostate
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作者 Vladimir Zaichick Sofia Zaichick 《Asian Journal of Urology》 CSCD 2019年第3期275-289,共15页
Objective:The aim of this study was to clarify the differences between the prostatic levels of chemical elements in patients with benign prostatic hyperplasia(BPH)and healthy male.Methods:We evaluated the prostatic le... Objective:The aim of this study was to clarify the differences between the prostatic levels of chemical elements in patients with benign prostatic hyperplasia(BPH)and healthy male.Methods:We evaluated the prostatic level of 66 chemical elements in 43 patients with BPH and 37 healthy males.Measurements were performed using five instrumental analytical methods.Results:In the hyperplastic prostates,we have observed a significant increase in the mean level of Bi,Cr,Hg,K,Sb,and Se accompanied a significant decrease in the mean level of Al,Ce,Cs,Dy,Er,Gd,Ho,La,Mo,Nd,Pb,Pr,Sm,Sn,Tb,Tm,U,and Y.No differences were found in the mean prostatic level of other chemical elements including Ag,Al,Au,B,Ba,Be,Br,Ca,Cd,Co,Cu,Fe,Li,Mg,Mn,Na,Nb,Ni,P,Rb,S,Sc,Si,Th,Ti,Tl,Yb,Zn,and Zr between BPH patients and healthy males.Conclusions:The finding of chemical element contents and correlation between pairs of chemical element mass fractions indicates that there is a great disturbance of prostatic chemical element metabolism in BPH gland.Trace elements Bi,Cr,Hg,K,Sb,and Se may be regarded as the possible tissue biomarkers of hyperplastic transformation of prostate gland.Obtained data did not confirm a critical role of Cd and Pb accumulation in the pathogenesis of BPH.A potential age-related Zn,Fe,and Se deficiency in the prostate tissue has not been found as being involved in the etiology of BPH. 展开更多
关键词 Benign prostate hyperplasia Prostatic chemical element contents Trace element supplementations Energy dispersive Xray fluorescence analysis Neutron activation analysis Inductively coupled plasma atomic emission and mass spectrometry
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Variations of nutrient element contents of plants and soils in the process of karst rocky desertification 被引量:1
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作者 Liping XIE Shijie WANG 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期176-176,共1页
关键词 喀斯特 土壤 植物 生态系统 营养元素
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REE Contents in Topsoil on the Loess Plateau and Effects of REE Applying on Crops 被引量:5
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作者 刘普灵 田均良 +1 位作者 李雅奇 琚彤军 《Journal of Rare Earths》 SCIE EI CAS CSCD 1995年第3期221-224,共4页
Eight rare earth elements(REE) in 104 topsoil samples collected from the Loess Plateau has been determined by using of INAA. The regional distribution of REE contents and its effectiveness of REE applying on crops in ... Eight rare earth elements(REE) in 104 topsoil samples collected from the Loess Plateau has been determined by using of INAA. The regional distribution of REE contents and its effectiveness of REE applying on crops in this area are discussed. The preliminary results showed that the mean concentration of most REE in this area approaches to those of China as a whole; and REE content in main type of soil of the Loess Plateau is as follows: gray cinnamon forest soil, Lou soil(stratified old manured loessal soil)> Heilu soil(dark loessal soil) . loessal soil>sierozem, and similar with the distribution pattern of soil clay contents in the soil which decrease gradually from southeast to northwest. This area may be suitable to apply REE in agriculture production. 展开更多
关键词 Rare earth elements contents Application in agriculture Loess Plateau
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A distributed measurement method for in-situ soil moisture content by using carbon-fiber heated cable 被引量:14
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作者 Dingfeng Cao Bin Shi +3 位作者 Honghu Zhu Guangqing Wei Shen-En Chen Junfan Yan 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2015年第6期700-707,共8页
Moisture content is a fundamental physical index that quantifies soil property and is closely associatedwith the hydrological, ecological and engineering behaviors of soil. To measure in-situ soil moisturecontents, a ... Moisture content is a fundamental physical index that quantifies soil property and is closely associatedwith the hydrological, ecological and engineering behaviors of soil. To measure in-situ soil moisturecontents, a distributed measurement system for in-situ soil moisture content (SM-DTS) is introduced.The system is based on carbon-fiber heated cable (CFHC) technology that has been developed to enhancethe measuring accuracy of in-situ soil moisture content. Using CFHC technique, a temperature characteristicvalue (Tt) can be defined from temperatureetime curves. A relationship among Tt, soil thermalimpedance coefficient and soil moisture content is then established in laboratory. The feasibility of theSM-DTS technology to provide distributed measurements of in-situ soil moisture content is verifiedthrough field tests. The research reported herein indicates that the proposed SM-DTS is capable ofmeasuring in-situ soil moisture content over long distances and large areas. 展开更多
关键词 in-situ soil moisture content Distributed measurement Carbon-fiber heated cable (CFHC) Fiber-optic sensing
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Influence of boron contents on properties of AlMgB films prepared by RF magnetron sputtering 被引量:3
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作者 Qu, Wenchao Wu, Aimin +2 位作者 Wu, Zhanling Bai, Yizhen Jiang, Xin 《Rare Metals》 SCIE EI CAS CSCD 2012年第2期164-167,共4页
Ternary AlMgB thin films were synthesized on silicon (100) substrate at 573 K by radio frequency (RF) magnetron sputtering method using one Al/Mg co-target and one boron target. The thickness of the as-deposited thin ... Ternary AlMgB thin films were synthesized on silicon (100) substrate at 573 K by radio frequency (RF) magnetron sputtering method using one Al/Mg co-target and one boron target. The thickness of the as-deposited thin film was controlled to 500 nm by adjusting deposition time. The influences of sputtering powers on the elemental contents and structural and mechanical properties were investigated by electron probe microanalysis (EPMA), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), and nanoindentation system. At the same time, the ball-on-disk tribometer was used to measure the friction behavior of the films. Experimental results indicate that the as-deposited boron-rich films are primarily amorphous structure and possess a dramatic high hardness up to 39 GPa with 99.03 at.% boron. Obviously, it has exceeded the hardness value of 32 GPa of pure AlMgB 14 bulk material prepared by sintering method. Furthermore, the friction coefficients of the thin films exhibit an average value as low as 0.3, which is considered as the effect of self-lubricating. 展开更多
关键词 AlMgB magnetron sputtering elemental content PROPERTIES
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Genesis of the Bianjiadayuan Pb-Zn polymetallic deposit, Inner Mongolia, China:Constraints from in-situ sulfur isotope and trace element geochemistry of pyrite 被引量:4
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作者 Kai-Rui Song Li Tang +7 位作者 Shou-Ting Zhang M. Santosh Christopher J. Spencer Yu Zhao Hao-Xing Li Liang Wang An-Li Zhang Yin-Qiang Sun 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第5期1863-1877,共15页
The Southern Great Xing’an Range (SGXR) which forms part of the eastern segment of the Central Asian Orogenic Belt (CAOB) is known as one of the most important Cu-Mo-Pb-Zn-Ag-Au metallogenic belts in China,hosting a ... The Southern Great Xing’an Range (SGXR) which forms part of the eastern segment of the Central Asian Orogenic Belt (CAOB) is known as one of the most important Cu-Mo-Pb-Zn-Ag-Au metallogenic belts in China,hosting a number of porphyry Mo (Cu),skarn Fe (Sn),epithermal Au-Ag,and hydrothermal veintype Ag-Pb-Zn ore deposits.Here we investigate the Bianjiadayuan hydrothermal vein-type Ag-Pb-Zn ore deposit in the southern part of the SGXR.Porphyry Sn ±Cu ± Mo mineralization is also developed to the west of the Ag-Pb-Zn veins in the ore field.We identify a five-stage mineralization process based on field and petrologic studies including (i) the early porphyry mineralization stage,(ii) main porphyry mineralization stage,(iii) transition mineralization stage,(iv) vein-type mineralization stage and (v) late mineralization stage.Pyrite is the predominant sulfide mineral in all stages except in the late mineralization stage,and we identify corresponding four types of pyrites: Py1 is medium-grained subhedral to euhedral occurring in the early barren quartz vein;Py2 is medium- to fine-grained euhedral pyrite mainly coexisting with molybdenite,chalcopyrite,minor sphalerite and galena;Py3 is fine-grained,subhedral to irregular pyrite and displays cataclastic textures with micro-fractures;Py4 occurs as euhedral microcrystals and forms irregularly shaped aggregate with sphalerite and galena.LA-ICP-MS trace element analyses of pyrite show that Cu,Pb,Zn,Ag,Sn,Cd and Sb are partitioned into pyrite as structurally bound metals or mineral micro/nano-inclusions,whereas Co,Ni,As and Se enter the lattice via isomorphism in all types of pyrite.The Cu,Zn,Ag,Cd concentrations gradually increase from Py1 to Py4,which we correlate with cooling and mixing of ore-forming fluid with meteoric water.Py2 contains the highest contents of Co,Ni,Se,Te and Bi,suggesting high temperature conditions for the porphyry mineralization stage.Ratios of Co/Ni (0.03-10.79,average 2.13) and sulphur isotope composition of sulfide indicate typical hydrothermal origin for pyrites.The δ^34SCDT values of Py1 (0.42‰-1.61‰,average 1.16‰),Py2 (-1.23‰ to 0.82‰,average 0.35‰),Py3 (-0.36‰ to 2.47‰,average 0.97‰),Py4 (2.51‰-3.72‰,average 3.06‰),and other sulfides are consistent with those of typical porphyry deposit (-5‰ to 5‰),indicating that the Pb-Zn polymetallic mineralization in the Bianjiadayuan deposit is genetically linked to the Yanshanian (JurassiceCretaceous) magmatic-hydrothermal events.Variations of d34S values are ascribed to the changes in physical and chemical conditions during the evolution and migration of the ore-forming fluid.We propose that the high Sn content of pyrite in the Bianjiadayuan hydrothermal vein-type PbeZn polymetallic deposit can be used as a possible pathfinder to prospect for Sn mineralization in the surrounding area or deeper level of the ore field in this region. 展开更多
关键词 Trace elements in-situ sulfur ISOTOPE PYRITE Bianjiadayuan deposit SOUTHERN Great Xing'an range
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Seismic performance of non-structural components and contents in buildings: an overview of NZ research 被引量:3
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作者 Rajesh P Dhakal Atefeh Pourali +5 位作者 Ali Sahin Tasligedik Trevor Yeow Andrew Baird Gregory Mac Rae Stefano Pampanin Alessandro Palermo 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2016年第1期1-17,共17页
This paper summarizes the research on non-structural elements and building contents being conducted at University of Canterbury in New Zealand. Since the 2010-2011 series of Canterbury earthquakes, in which damage to ... This paper summarizes the research on non-structural elements and building contents being conducted at University of Canterbury in New Zealand. Since the 2010-2011 series of Canterbury earthquakes, in which damage to non-structural components and contents contributed heavily to downtime and overall financial loss, attention to seismic performance and design of non-structural components and contents in buildings has increased exponentially in NZ. This has resulted in an increased allocation of resources to research leading to development of more resilient non-structural systems in buildings that would incur substantially less damage and cause little downtime during earthquakes. In the last few years, NZ researchers have made important developments in understanding and improving the seismic performance of secondary building elements such as partitions, facades, ceilings and contents. 展开更多
关键词 non-structural elements building contents drywall partition CLADDING suspended ceilings seismicperformance assessment fragility analysis experimental evaluation loss estimation
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Evidence of fluid evolution of Baoshan Cu−Pb−Zn polymetallic deposit:Constraints from in-situ sulfur isotope and trace element compositions of pyrite 被引量:3
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作者 Jun-ke ZHANG Yong-jun SHAO +4 位作者 Ke CHEN Hua-jie TAN Rui-chang TAN Tian-dong ZHANG Zhong-fa LIU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第11期3530-3548,共19页
In-situ LA-ICP-MS and S isotopes of pyrite from the Baoshan Cu polymetallic deposit were conducted to investigate the ore-forming process and the enrichment mechanism of elements.Three generations of pyrite (Py Ⅰ,Py ... In-situ LA-ICP-MS and S isotopes of pyrite from the Baoshan Cu polymetallic deposit were conducted to investigate the ore-forming process and the enrichment mechanism of elements.Three generations of pyrite (Py Ⅰ,Py Ⅱ,and Py Ⅲ) in the skarn-type ores and pyrite in the carbonate-hosted sulfide ores from central,western,and northern(C_Py,W_Py,and N_Py) mining districts are selected for comparison.Compared with Py Ⅰ and Py Ⅲ,the contents of most elements in Py Ⅱ are apparently higher.The As and Se contents are high within a wide range and are decoupled in the growth band of the C_Py.The highest As,Se,and Pb contents were found in W_Py and N_Py.These results indicate the drastic changes in the temperature and fluid mixing during the mineralization.The occurrence of fluctuation and change in temperature and f(O_(2)) was triggered by intermittent pulses of magmatic-hydrothermal fluids,mixing with meteoric water,and water-rock interactions.The sulfur isotopes of all species of pyrite indicated the magmatic source.The change in the f(O_(2)) conditions caused slight differences in the sulfur isotope compositions.Consequently,a metallogenic model was proposed to explain the ore-forming processes. 展开更多
关键词 PYRITE trace element in-situ S isotope hydraulic fracturing fluid mixing
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