期刊文献+
共找到463篇文章
< 1 2 24 >
每页显示 20 50 100
Magmatic to Hydrothermal Evolution of Bianjiadayuan Ag-Pb-Zn-Sn Deposit,Northeast China:A Quartz Texture and Trace Elements Study
1
作者 Xin Wang Nan Qi +3 位作者 Xinyou Zhu Xi-Heng He Haowei Gu Xiaohua Deng 《Journal of Earth Science》 2025年第4期1493-1504,共12页
Quartz trace elements are extensively employed in studying magmatic evolution,fluid evolution,and metal enrichment.The Bianjiadayuan Ag-Pb-Zn-Sn deposit is a typical magmatichydrothermal system in northeastern China,h... Quartz trace elements are extensively employed in studying magmatic evolution,fluid evolution,and metal enrichment.The Bianjiadayuan Ag-Pb-Zn-Sn deposit is a typical magmatichydrothermal system in northeastern China,however,studies on its complex magmatic-hydrothermal evolution are limited.This study investigates the quartz from the Bianjiadayuan deposit to gain insight into the physicochemical evolution of mineralization using cathodoluminescence(CL)textures and laser ablation-inductively coupled plasma-mass spectrometry(LA-ICP-MS)of quartz.Five types quartz(Q1 to Q5)were identified.From Q1 in quartz porphyry to Q5 in Ag-Pb-Zn veins,the CL intensity and Ti content gradually decreases,and Ge,Ge/Ti,and Al/Ti ratios increase,indicating a temperature decline from magmatic to hydrothermal stages.The Sb content shows an opposite trend to Ti content,correlating positively with Ge content in quartz,suggesting that Sb content could also be temperature-dependent.These trace elements in quartz indicate cooling is critical for Ag mineralization.Furthermore,quartz phenocryst(Q1)from the quartz porphyry shows low Al/Ti(mostly<4)and Ge/Ti ratios(<0.04),suggesting a low degree of magmatic evolution.The Sb content in Q5 from Ag-Pb-Zn-quartz veins(>1 ppm,mostly tens of ppm)is notably higher compared to quartz in other lithologies including Sn-bearing quartz veins(<1 ppm),suggesting that Sb contents can serve as an effective indicator of Ag mineralization. 展开更多
关键词 QUARTZ trace elements Ag mineralization Ag-Pb-Zn-Sn deposit Bianjiadayuan
原文传递
Assessment of trace elements distribution and sources from snowpits in the Lambert Glacier region,coastal East Antarctica
2
作者 Yalalt Nyamgerel Soon Do Hur +3 位作者 Tseren-Ochir Soyol-Erdene Cunde Xiao Hyejung Jung Jeonghoon Lee 《Geoscience Frontiers》 2025年第3期425-437,共13页
The measurement of trace elements in Antarctic snow is crucial for understanding historical atmospheric geochemical changes and circulation patterns.However,studies on their spatial distributions remain limited,partic... The measurement of trace elements in Antarctic snow is crucial for understanding historical atmospheric geochemical changes and circulation patterns.However,studies on their spatial distributions remain limited,particularly those evaluating multiple metals across several snowpits,making interpretation challenging.This study investigates the distributions and sources of trace elements-including Cd,Ba,Pb,U,Bi,V,Mn,Fe,Cu,Zn,and As-across four snowpits in the Lambert Glacier Basin,East Antarctica.The trace elements exhibit site-,element-,and season-dependent variations,with higher concentrations observed at inland sites.In contrast,δ^(18)O and ion concentrations decrease with increasing distance from the coast and elevation,underscoring the influence of marine emissions.Crustal sources primarily contributed to Ba,U,V,Mn,and Fe,while non-crustal sources predominantly contributed to Cd,Bi,Zn,Pb,Cu,and As.Positive matrix factorization(PMF)analysis indicates that trace element concentrations in Pits 2 and 3 are influenced by both crustal and non-crustal sources,while Pit 4 reflects a mixed-source influence.Pit 1(coastal site)also indicates the mixed sources with influence of a highly dynamic marine climate and environment.The PMF results reveal similarities in emission sources and atmospheric transport patterns across the snowpits,facilitating a more comprehensive interpretation of longer ice core records.Overall,this study provides valuable insights into trace element distributions and enhances our understanding of past environmental and climatic conditions. 展开更多
关键词 trace elements Spatial variation ANTARCTICA Lambert Glacier Basin Positive matrix factorization
暂未订购
Trace Elements and Tumor: Research Progress
3
作者 Zhiguang Wen Cailing Wei Siwu Fu 《Proceedings of Anticancer Research》 2025年第6期1-9,共9页
This review systematically summarizes the core advances in the field of trace elements and tumors,and clarifies the dual roles of key elements such as Zn,Cu,Fe,Se,Mn,and Ni in tumorigenesis(e.g.,DNA damage repair),tum... This review systematically summarizes the core advances in the field of trace elements and tumors,and clarifies the dual roles of key elements such as Zn,Cu,Fe,Se,Mn,and Ni in tumorigenesis(e.g.,DNA damage repair),tumor progression(e.g.,tumor microenvironment regulation),and therapeutic response-these elements not only possess tumor-suppressive potential but can also contribute to tumorigenesis.Meanwhile,it confirms the breakthrough value of multi-omics technologies and organoid models in deciphering the“element-cell-tumor”interaction mechanisms,which overcomes the limitations of traditional in vitro experiments and also points out the core directions for subsequent clinical research. 展开更多
关键词 TUMOR trace elements TREATMENT
暂未订购
Wavy Distribution of Trace Elements in Phytolacca Samples from Different Areas 被引量:4
4
作者 杜莹 欧阳荔 +1 位作者 刘雅琼 王京宇 《Journal of Chinese Pharmaceutical Sciences》 CAS 2004年第4期271-275,共5页
To study the distribution of 25 elements, i.e. Be, Cd, Ce, Cr, Cu, Dy, Er,Eu, Gd, Ge, Ho, La, Lu, Mo, Nd, Pb, Pr, Sm, Sr, Tb, Tl, Tm, Y, Yb and Zn in Phytolacca, atraditional Chinese medicinal herb, collected from nin... To study the distribution of 25 elements, i.e. Be, Cd, Ce, Cr, Cu, Dy, Er,Eu, Gd, Ge, Ho, La, Lu, Mo, Nd, Pb, Pr, Sm, Sr, Tb, Tl, Tm, Y, Yb and Zn in Phytolacca, atraditional Chinese medicinal herb, collected from nine areas of P. R. China. Methods Twenty-fiveelements in Phytolacca including essential elements, toxic elements and rare earth elements intraditional Chinese medicinal herbs from different areas were analyzed by ICP-MS. Results The 25elements in Phytolacca were determined by ICP-MS under optimized conditions. The detection limitswere 0.003 -0.71 ng·mL^(-1). The recoveries were 88% - 118% . The relative standard deviations ofthe measurements were 1.7% - 13.3%. Conclusion The determined concentrations of elements inPhytolacca acinosa Roxb vary from one area to another; however, the distribution tendency ofelements in all the samples is similar. The distribution tendency of rare earth elements inPhytolacca acinosa Roxb is consistent with that in nature. 展开更多
关键词 traditional chinese medicinal herbs trace elements ICP-MS DISTRIBUTION
暂未订购
Study on the Major and Trace Elements in Soil of Yunnan Farmland
5
作者 徐娟 刘刚 +3 位作者 赵兴祥 赵帅群 任静 胡建飞 《Agricultural Science & Technology》 CAS 2014年第12期2141-2144,共4页
In order to investigate the distribution of soil available micronutrients, and provide a theoretical basis for management of fertilizing reasonably on crops, the contents of major and trace elements (P, K, Ca, Mg, Cu... In order to investigate the distribution of soil available micronutrients, and provide a theoretical basis for management of fertilizing reasonably on crops, the contents of major and trace elements (P, K, Ca, Mg, Cu, Fe, Zn, and Mn) in farm- land soil collected from Yunnan Province were determined by inductively coupled plasma-mass spectrometry (ICP-MS), the contents and distribution of major and trace elements were also studied. The results showed that the contents of available P, K were balance, available Ca, Mg were deficient, and available Cu, Fe, Zn, Mn were very plentiful. Major and trace elements distribution of different landform areas were obviously different. The contents of trace elements (Fe, Zn and Mn) of central Yunnan Red Plateau were significantly higher than those of Hengduan Mountains in western Yunnan and those of karst plateau in eastern Yunnan. The contents of available P, K, and Ca gradually declined from west to east, while the content of available Cu rose gradually from west to east. The results are reference value to elements determination and agricultural production in farmland soils. 展开更多
关键词 ICP-MS Soil of Yunnan farmland Major elements trace elements CONTENT
在线阅读 下载PDF
Clinical and experimental study on gastric mucosal Pathology DNA cAMP and trace elements of pixu patients
6
作者 尹光耀 何雪芬 尹玉芬 《World Journal of Gastroenterology》 SCIE CAS CSCD 1996年第1期44-50,共7页
AIMS The paper studies the relationship between spleen deficiency substance,spleen deficiency and gastric cancer. METHODS We adopted the IBAS 2000 image analysis system,501B SEM with 9100/60 energy chromatic dispersin... AIMS The paper studies the relationship between spleen deficiency substance,spleen deficiency and gastric cancer. METHODS We adopted the IBAS 2000 image analysis system,501B SEM with 9100/60 energy chromatic dispersing X-ray analysis instrument technique,histologic chemistry and radio-immunity means to assay the ultramicro structure,in- testinal rnetaplasia subtypes,cAMP,DNA,trace element series and their oxides of the patients' gastric mucosa. RESULTS The incidence rates of gastric cancer,incom- plete colonic intestinal metaplasia and“background lesion”of spleen deficiency with Qi stagnation patients are remarkably higher than those of spleen Qi deficiency patients(P<0.05- 0.001 ).The levels of gastric mucosa cAMP,Zn,Cu,ZnO and CuO decreased from complete to incomplete intestinal meta- plasia and from small to colonic intestinal metaplasia,while DNA increased in the above sequence(P<0.05-0.001 ).The lev- els of DNA,cAMP,Zn,Cu,ZnO and CuO in gastric mucosa of incomplete colonic intestinal metaplasia tissue are not remark- ably different from those in gastric cancer tissue. CONCLUSION Gastric diseases of spleen dificiency with Qi stagnation has the tendency of cancerization; There is a close relationship between the incidence of incomplete colonic intestinal metaplasia and gastric cancer. 展开更多
关键词 Spleen asthenia gastric macosa DNA Cyclic AMP trace elements
暂未订购
Study on Trace Elements in Rehmannia glutinosa Libosch. by Principal Component Analysis and Clustering Analysis
7
作者 申明金 陈丽 曹洪斌 《Agricultural Science & Technology》 CAS 2013年第12期1764-1768,共5页
[Objective] This study aimed to investigate the trace elements in Rehman- nia glutinosa Libosch. by using principal component analysis and clustering analysis. [Method] Principal component analysis and clustering anal... [Objective] This study aimed to investigate the trace elements in Rehman- nia glutinosa Libosch. by using principal component analysis and clustering analysis. [Method] Principal component analysis and clustering analysis of R. glutinosa medicinal materials from different sources were conducted with contents of six trace elements as indices. [Result] The principal component analysis could comprehen- sively evaluate the quality of R. glutinosa samples with objective results which was consistent with the results of clustering analysis. [Conclusion] Principal component analysis and clustering analysis methods can be used for the quality evaluation of Chinese medicinal materials with multiple indices. 展开更多
关键词 Rehmannia glutinosa Libosch. (Radix Rehmanniae) trace elements Principal component analysis Clustering analysis
在线阅读 下载PDF
Determination of Trace Elements in Potatoes by Flame Atomic Absorption Spectrometry
8
作者 王宁芳 《Agricultural Science & Technology》 CAS 2014年第5期716-717,723,共3页
[Objective] This study aimed to analyze the contents of trace elements in potatoes from different production areas in Qinghai Province. [Method] By flame atomic absorption spectrometry (FAAS), the contents of variou... [Objective] This study aimed to analyze the contents of trace elements in potatoes from different production areas in Qinghai Province. [Method] By flame atomic absorption spectrometry (FAAS), the contents of various trace elements in potatoes were determined. [Result] Potatoes contain abundant trace elements such as Cu, Zn, Fe, Mn, Ca, K and Mg. To be specific, the contents of Ca, K and Mg were relatively high. [Conclusion] By using FAAS, the relative standard deviation was 1.17%-2.75% and the recovery rate was 97%-99.5%, indicating accurate and reli-able results with high precision. 展开更多
关键词 POTATO Flame atomic absorption spectrometry trace elements Relative deviation PRECISION
在线阅读 下载PDF
Different Carbon Fractions in Soils and Their Relationship with Trace Elements Content
9
作者 Lubica Pospisilova Petr Skarpa Marie Konecna 《Journal of Life Sciences》 2011年第4期316-321,共6页
Luvisols, Stagnogleys and Cambisols, although less fertile, are used intensively for mixed farming, grazing and as forestland. Therefore we aimed our study at determination of total organic carbon (TOC) content, hum... Luvisols, Stagnogleys and Cambisols, although less fertile, are used intensively for mixed farming, grazing and as forestland. Therefore we aimed our study at determination of total organic carbon (TOC) content, humic substances (HS) content, humic acids (HA) content, fulvic acids (FA), hot water extractable carbon (Chw) content and content total and labile trace elements content. Humic substances quality was assessed by HA/FA ratio and by coloured indexes measured in ultraviolet and visible UV-VIS spectral range. The total and labile contents of Zn, Cd, Cu, Co, Pb, Mo and Se were determined by flame or electro-thermal atomic absorption spectrometry after extraction of the soil samples in the aqua regia (total content) and in the solution of 0.01 M CaCI2. Total and labile trace elements content was correlated with determined carbon fractions and soil reaction. Results showed that studied soils content low amount of TOC and had low quality of humic substances. HA/FA ratio was less than 1 and colour indexes were higher than 4. All determined carbon fractions correlated with labile form of Zn and Cd. Correlation between soil reaction and total zinc content was found. Significant effect of humic substances content on to water-soluble forms of heavy metals was detected. 展开更多
关键词 Humic acids fulvic acids hot water extractable carbon humus fractionation labile trace elements total trace elements.
在线阅读 下载PDF
Effect of Trace Elements in Seed Coating Agent on Peanut Growth 被引量:1
10
作者 谢文娟 曾德芳 +1 位作者 赵会方 邓清香 《Agricultural Science & Technology》 CAS 2013年第6期922-924,936,共4页
[Objective] This study aimed to investigate the effect of trace elements in peanut seed coating agent. [Method] Different concentrations of trace elements Fe and B were added into peanut coating agent, then the germin... [Objective] This study aimed to investigate the effect of trace elements in peanut seed coating agent. [Method] Different concentrations of trace elements Fe and B were added into peanut coating agent, then the germination rate and plant height of the seeds treated by different agents were measured to decide the best formula. [Result] The germination rate and plant height of the seeds treated with seed coating agent was obviously increased. Adding trace elements Fe and B could increase the peanut yield, and 1.5% Fe and 1% B gave the best result. [Conclusion] This study will provide reference for modifying the seed coating agent formula. 展开更多
关键词 trace elements Peanut seed coating agent Yield improvement
在线阅读 下载PDF
Emission control strategies of hazardous trace elements from coal-fired power plants in China 被引量:19
11
作者 Adwek George Boxiong Shen +2 位作者 Dongrui Kang Jiancheng Yang Jiangze Luo 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第7期66-90,共25页
China’s energy dependents on coal due to the abundance and low cost of coal.Coal provides a secure and stable energy source in China.Over-dependence on coal results in the emission of Hazardous Trace Elements(HTEs)in... China’s energy dependents on coal due to the abundance and low cost of coal.Coal provides a secure and stable energy source in China.Over-dependence on coal results in the emission of Hazardous Trace Elements(HTEs)including selenium(Se),mercury(Hg),lead(Pb),arsenic(As),etc.,from Coal-Fired Power Plants(CFPPs),which are the major toxic air pollutants causing widespread concern.For this reason,it is essential to provide a succinct analysis of the main HTEs emission control techniques while concurrently identifying the research prospects framework and specifying future research directions.The study herein reviews various techniques applied in China for the selected HTEs emission control,including the technical,institutional,policy,and regulatory aspects.The specific areas covered in this study include health effects,future coal production and consumption,the current situation of HTEs in Chinese coal,the chemistry of selected HTEs,control techniques,policies,and action plans safeguarding the emission control.The review emphasizes the fact that China must establish and promote efficient and clean ways to utilize coal in order to realize sustainable development.The principal conclusion is that cleaning coal technologies and fuel substitution should be great potential HTEs control technologies in China.Future research should focus on the simultaneous removal of HTEs,PM,SOx,and NOx in the complex flue gas. 展开更多
关键词 COAL Coal-fired power plants POLICIES Heavy trace elements
原文传递
The Estimation of Soil Trace Elements Distribution and Soil-Plant-Animal Continuum in Relation to Trace Elements Status of Sheep in Huangcheng Area of Qilian Mountain Grassland,China 被引量:12
12
作者 WANG Hui LIU Yong-ming +7 位作者 QI Zhi-ming WANG Sheng-yi LIU Shi-xiang LI Xia WANG Hai-jun WANG Xiao-li XIA Xin-chao ZHU Xin-qiang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第1期140-147,共8页
The purpose of the present study was to survey contents of trace elements of Cu, Mn, Fe, and Zn in the surface layer (0-20 cm) in the soil, pasture and serum of sheep in Huangcheng area of Qilian mountain grassland,... The purpose of the present study was to survey contents of trace elements of Cu, Mn, Fe, and Zn in the surface layer (0-20 cm) in the soil, pasture and serum of sheep in Huangcheng area of Qilian mountain grassland, China. Also the soil-plantanimal continuum was analyzed. Soil (n=300), pasture (n=60), and blood serum samples from sheep (n=480) were collected from Huangcheng area of Qilian mountain grassland, China. The contents of trace element in the samples were analyzed by atomic absorption spectrophotometer after digestion. The soil trace elements density distribution shows a ladder-like pattern distribution. Equations developed in the present study for prediction of Fe (R2=0.943) and Zn (R2=0.882) had significant R2 values. 展开更多
关键词 trace elements minerals deficiency soil type Qilian mountain grassland correlation
在线阅读 下载PDF
Sedimentary cycles of trace elements in Salawusu River Valley since 150 ka BP 被引量:10
13
作者 YAO Chun-xia1,2, LI Bao-sheng1,2, JIN He-ling3, David Dian Zhang4, YAN Man-cun5, ZHU Yi-zhi2, LI Hou-xin1, ZHANG Yu-hong1, Luo Kai-li1 (1. Dept. of Geography, South China Normal University, Guangzhou 510631, China 2. State Key Laboratory of Loess 《Journal of Geographical Sciences》 SCIE CSCD 2002年第1期65-71,共7页
The paper makes some analyses on 11 trace elements in the Milanggouwan stratigraphical section in the Salawusu River valley, which is regarded as a prototype geology-palaeoclimate record since 150 ka BP. The results s... The paper makes some analyses on 11 trace elements in the Milanggouwan stratigraphical section in the Salawusu River valley, which is regarded as a prototype geology-palaeoclimate record since 150 ka BP. The results show that the content and variation of trace elements has experienced remarkably regular changes in the pace with coarse and fine sedimentary cycles of palaeo-aeolian sands to its overlying fluvio-lacustrine facies or/and palaeosols. The trace elements with chemical properties of relatively active (V, Sr, Cu, Ni, As) and relatively stable (P, Pb, Rb, Mn, Nb, Zr) are a manifestation of the corresponding 27 changeable cycles between peak and valley values, appearing a multi-fiuctuational process line of relative gathering and migration since then. The low numerical value distribution of these two types of trace elements in the aeolian sand facies represents erosion and accumulation under wind force during the cold-dry climate. Whereas their enrichments in both fluvio-lacustrine facies and palaeosols are related to the valley’s special low-lying physiognomic position between the Ordos Plateau and the Loess Plateau under the warm and humid climate conditions. The above relatively migrated and gathered change of the trace elements is the result of 27 climatic cycles of cold-dry and warm-humid, which is probably caused by repeated alternations of winter monsoon and summer monsoon in the Mu Us Sandy Land influenced by the climate vicissitudes in northern hemisphere during glacial and interglacial periods since 150 ka BP. 展开更多
关键词 Salawusu River valley Milanggouwan section CYCLE trace elements 150 ka BP PALAEOCLIMATE
在线阅读 下载PDF
Ages, Trace Elements and Hf-Isotopic Compositions of Zircons from Claystones around the Permian-Triassic Boundary in the Zunyi Section, South China: Implications for Nature and Tectonic Setting of the Volcanism 被引量:9
14
作者 Qiuling Gao Zhong-Qiang Chen +6 位作者 Ning Zhang William L.Griffin Wenchen Xia Guoqing Wang Tengfei Jiang Xuefei Xia Suzanne Y.O'Reilly 《Journal of Earth Science》 SCIE CAS CSCD 2015年第6期872-882,共11页
A growing body of evidence shows that volcanism near the Permian-Triassic boundary(PTB) may be crucial in triggering the Permian–Triassic(P–Tr) mass extinction. Thus, the ash beds near the PTB in South China may... A growing body of evidence shows that volcanism near the Permian-Triassic boundary(PTB) may be crucial in triggering the Permian–Triassic(P–Tr) mass extinction. Thus, the ash beds near the PTB in South China may carry information on this event. Three volcanic ash layers, altered to clay, outcropped in the PTB beds in Zunyi Section, Guizhou Province, Southwest China. The U-Pb ages, trace elements, and Hf-isotope compositions of zircon grains from these three ash beds were analyzed using LA-ICPMS and LA-MC-ICPMS. The zircons are mainly magmatic in origin(241-279 Ma) except for two inherited/xenocrystic zircons(939 and 2 325 Ma). The ages of these magmatic zircons indicate three episodes of magmatism which occurred around the MiddleLate Permian boundary(-261.5 Ma, MLPB), the Wuchiapingian-Changhsingian boundary(-254.5 Ma, WCB), and the PTB(-250.5 Ma), respectively. The first two episodes of magmatism near the MLPB and WCB may be attributed to magmatic inheritance or re-deposition. All magmatic zircons share similar trace-element and Hf-isotope compositions. They have Y, Hf, Th and U contents and Nb/Ta ratios are typical of zircons from silicic calc-alkaline magmas. These zircons also exhibit enriched Hf-isotope compositions with _(εHf)(t) values of-11.4 to +0.2, which suggests that the three magmatic episodes involved melting of the continental crust. The more enriched Hf-isotope composition (_(εHf)(t)=-11.4--4.8) of Bed ZY13(-250.5 Ma) implies more input of ancient crustal material in the magma. Integration of the Hf-isotope and trace-element compositions of magmatic zircons suggest that these three episodes of magmatism may take place along the convergent continent margin in or near southwestern South China as a result of the closure of the Palaeo-Tethys Ocean. 展开更多
关键词 Permian-Triassic boundary zircon trace elements Hf isotope silicic volcanism convergent continental margin South China.
原文传递
Mineralogy,distribution,occurrence and removability of trace elements during the coal preparation of No.6 coal from Heidaigou mine 被引量:12
15
作者 Xiangfei Bai Yue Wang Wenhua Li 《International Journal of Coal Science & Technology》 EI CAS 2014年第4期402-420,共19页
Optical microscopy and scanning electron microscopy in conjunction with energy dispersed X-ray spectrometry(SEM–EDX)were used to study the minerals and the concentrations of 33 trace elements in No.6 coal from Heidai... Optical microscopy and scanning electron microscopy in conjunction with energy dispersed X-ray spectrometry(SEM–EDX)were used to study the minerals and the concentrations of 33 trace elements in No.6 coal from Heidaigou mine.The distributions,organic affinity and removability of 18 trace elements were studied by float-sink experiments.A determination of the maceral groups was also undertaken.A high mineral content,dominated by kaolinite,was found in No.6 coal from Heidaigou mine.The bauxite content was relatively high and it was mainly present as individual particles in fusinite lumens or was intimately intergrown with carbonate minerals.The pyrite and quartz contents were low.Some marcasite with a parallel twin structure was observed by cross-polar reflected light.A small amount of bean-like goyazite was present in the calcite.The weighted trace element content in Heidaigou formations is relatively low,which is beneficial for coal processing and utilization.The concentrations of Ga,Hg,Pb,Se,Th,Ta are relatively high compared with the average values of Chinese coals.As,Hg,Mo,Ge,Ga,Ta,Ti,W,Mn are mainly present in minerals while B,Be,Th,P,Sc,Sr,V,Y,Yb are mainly found in organic matter.As,Ge,Hg,Mo are mainly present in sulfides and Be,Th,P,Sc,Sr,Y,Yb are mainly present in inertinite.B and V are mainly present in vitrinite.The high organic affinity and the low theoretical removability of most trace elements cause difficulties in removing them during coal preparation. 展开更多
关键词 trace elements OCCURRENCE Organic affinity-Removability Heidaigou coal
在线阅读 下载PDF
A Marine or Continental Nature of the Deltas in the Early Cretaceous Lingshandao Formation--Evidences from Trace Elements 被引量:12
16
作者 YANG Renchao FAN Aiping +1 位作者 HAN Zuozhen A.J.(Tom)VAN LOON 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第1期367-368,共2页
Objective A succession with well-developed soft-sediment deformation structures and well-exposed gravity-flow deposits in the Early Cretaceous Lingshandao Formation has caused considerable controversy on whether the n... Objective A succession with well-developed soft-sediment deformation structures and well-exposed gravity-flow deposits in the Early Cretaceous Lingshandao Formation has caused considerable controversy on whether the nondisputed deltaic environment was marine or continental.This dispute cannot be solved by mere sedimentological analysis and,moreover,too few fossils are present to be decisive. 展开更多
关键词 Cr PPM Evidences from trace elements
在线阅读 下载PDF
Effect of trace elements on growth of Pinus tabulaeformis seedling 被引量:7
17
作者 刘晓东 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第4期285-288,337,共4页
The stimulative effect of trace elements on seed germination and seedling growth of Pinus tabulaeformis was tested. The experiments were carried out on seed soak and topdressing with different trace elements and varie... The stimulative effect of trace elements on seed germination and seedling growth of Pinus tabulaeformis was tested. The experiments were carried out on seed soak and topdressing with different trace elements and varied concentrations at the nursery of Gardens Research Institute, Harbin, in 2000-2001. The experimental results showed that soaking seed with 1% and 0.2% concentrations of Mn element produced best result for seed germination, and the germination rate was increased by 9%~19% for the seeds treated with 1% concentration and 12%~14% for the seeds treated with 0.2% concentration compared with the control group. The seeds treated with boron element had lowest germination rate. For trace element topdressing, Mn and Mo elements presented good result for seedling growth and the treatment with low concentration was even better. The height or chlorophyll content of the seedlings with spray of low-concentration Mn and Mo element was much higher than that of untreated ones. In the contrast to the treating method of seed soak, topdressing (application of spraying on foliage) had evident effect on seedling growth. 展开更多
关键词 Pinus tabulaeformis trace element Seed soaking TOPDRESSING Seed germination Seedling growth
在线阅读 下载PDF
Impact of coal gangue on the level of main trace elements in the shallow groundwater of a mine reclamation area 被引量:21
18
作者 Li Wei Chen Longqian +2 位作者 Zhou Tianjian Tang Qibao Zhang Ting 《Mining Science and Technology》 EI CAS 2011年第5期715-719,共5页
Coal gangue is the most used filling material during reclamation of areas suffering subsidence from min- ing. Main trace element levels (F, As, Hg, and Pb) in shallow groundwater in the reclamation area may be affecte... Coal gangue is the most used filling material during reclamation of areas suffering subsidence from min- ing. Main trace element levels (F, As, Hg, and Pb) in shallow groundwater in the reclamation area may be affected by leaching from the gangue. This can has an impact on the application of the water for agricul- tural irrigation or use as drinking water. Therefore, it is of great significance to understand the effect coal gangue has on the shallow groundwater of a reclaimed area. We studied the effect of coal gangue on fluo- rine, arsenic, mercury, and lead levels in the shallow groundwater of a reclamation area by testing the water and the coal gangue. One well near the reclamation area was used as a control well and element levels in water from this well and from the soil next to the well were also measured. The results show that the levels of these elements are increasing in the reclamation area over time. The increase in fluorine, arsenic, mercury, and lead in monitor wells varies from 7.42% to 8.26%, from 7.13% to 7.90%, from 4.85% to 6.48%, and from 4.69% to 6.42%, respectively. Fluorine and arsenic levels are lower in monitor wells than in the control water. The other elements are found in greater concentration than in the control. The Nemerow index also indicates that the shallow groundwater in the reclamation area I is moderately affected by the back-filling coal gangue, while the shallow groundwater in the reclamation area II and III are slightly affected by the back-filling coal gangue. This shallow groundwater could be used for agri- cultural irrigation or for drinking. 展开更多
关键词 Coal gangue Main trace elements Shallow groundwater Reclamation area Nemerow index
在线阅读 下载PDF
Application of ICP-AES with Microwave Digestion to Detect Trace Elements in Oysters from Jiaozhou Bay,China 被引量:6
19
作者 ZHENG Kang YAN Cuiwei 《Journal of Ocean University of China》 SCIE CAS 2011年第3期301-304,共4页
Using ICP-AES with microwave digestion, we determined the concentrations of 16 trace elements in oysters from six sampling points in Jiaozhou Bay.The distributions of the wholesome elements Zn, Fe and Mn, and heavy me... Using ICP-AES with microwave digestion, we determined the concentrations of 16 trace elements in oysters from six sampling points in Jiaozhou Bay.The distributions of the wholesome elements Zn, Fe and Mn, and heavy metals such as As,Cd,Hg and Pb were studied.The oysters collected are all rich in the wholesome trace elements,and the oysters from Licun River have the highest concentrations of the three wholesome trace elements.The concentrations of heavy metals in oysters from Licun River are the highest and those from Hongdao are the lowest. Compared with the domestic and foreign sea-areas,the heavy metal contents in the oysters from Jiaozhou Bay are less in amount than those from some developed countries, and more than those in Southeast China.This implies that the Jiaozhou Bay's oysters have been polluted by the environment to some extent. 展开更多
关键词 OYSTERS trace elements microwave digestion ICP-AES Jiaozhou Bay
在线阅读 下载PDF
Effects of Feed Fermentation on Chemical Fractionation of Trace Elements in Feed and Pig Manure and Skatole Content in Pig Manure 被引量:2
20
作者 盛清凯 战余铭 +3 位作者 孙延军 李祥明 孟宪利 赵红波 《Agricultural Science & Technology》 CAS 2016年第4期916-919,共4页
[Objective] This study aimed to promote the combination of cultivation and livestock farming, and to explore an environment-protecting farming style. [Method]The effects of anaerobically fermented complete compound so... [Objective] This study aimed to promote the combination of cultivation and livestock farming, and to explore an environment-protecting farming style. [Method]The effects of anaerobically fermented complete compound sow feed, added with Lactobacillus and Bacillus subtilis, on the chemical fractionation of copper, iron, zinc and manganese in feed and pig manure and skatole content in pig manure were investigated. [Result] Compared with those in the non-fermented feed, in the fermented feed and pig manure, the acetic acid-extractable copper, iron, zinc and manganese contents increased significantly(P0.05), the reduced copper and iron contents increased significantly(P 0.05), the oxidized copper and iron contents reduced significantly(P0.05), and the residual copper contents remained unchangeable(P0.05). The pH value of fermented feed decreased significantly(P0.05), and that of pig manure increased significantly(P0.05). The skatole content in pig manure decreased significantly(P 0.01). The Lactobacillus abundance and amylase and cellulase activity increased significantly(P 0.05). [Conclusion] The fermentation of feed changed the chemical fractionation of copper, iron, zinc and manganese in feed and pig manure, and reduced the manure odor. 展开更多
关键词 FERMENTATION FEED MANURE trace element Chemical fractionation SKATOLE
在线阅读 下载PDF
上一页 1 2 24 下一页 到第
使用帮助 返回顶部