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Predictive Study of Trace Metal Pollution of Gold Panning Sites in Birimian Formations: Case of the Yaouré Furrow (Côte d’Ivoire)
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作者 Tonga Paul Tiemoko Gbele Ouattara Kouassi Ernest Ahoussi 《Open Journal of Applied Sciences》 2024年第7期1691-1714,共24页
The present study was carried out on small-scale gold mining sites in the Yaouré region of Côte d’Ivoire. This region is geologically representative of the Birimian formations (2.1 Ga) of West Africa. The a... The present study was carried out on small-scale gold mining sites in the Yaouré region of Côte d’Ivoire. This region is geologically representative of the Birimian formations (2.1 Ga) of West Africa. The aim is to determine the potentially toxic trace metals (TMEs) generated by these sites, with a view to preventing possible contamination and/or metal pollution of the waters that provide fish products for local populations. To this end, a sampling campaign was carried out, resulting in the collection of 20 mining waste samples analyzed by X-ray fluorescence spectrometry (XRF) and 10 by X-ray diffractometer (XRD). The XRF analysis detected 06 predominant TMEs: arsenic, chromium, copper, nickel, zinc and vanadium. Statistical analysis was carried out to determine the distributions and correlations between these ETMs. To assess contamination and/or pollution levels, the following indices were calculated on the basis of reference concentrations of upper continental crust MTEs: Enrichment Factor, Geo-accumulation Index, Concentration Factor, Degree of contamination and those related to ecological risks. The results of statistical analyses and indices have shown that arsenic and chromium are the most predominant and can be, depending on the chemical form, potentially more toxic. The results of the DRX analysis show the occurrence of several minerals carrying these two MTEs, especially that of a rare mineral, Stenhuggarite, an arsenic oxide linked to hydrothermal veins. The majority of gold mining operations in West Africa are located in the birimian zone, hence the need for environmental monitoring by the relevant authorities, to prevent potential ecological risks to water and possibly health risks via the food chain. 展开更多
关键词 Small-Scale Mining metallic trace elements Mining Discharges CONTAMINATION POLLUTION CONTAMINATION POLLUTION Index
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Investigating Catalase and Carbonic Anhydrase Enzyme Activities and Levels of Certain Trace Elements and Heavy Metals in Patients with Primary and Metastatic Hepatic Carcinoma 被引量:1
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作者 Ayse Arslan Halit Demir Harun Arslan 《Journal of Cancer Therapy》 2013年第8期1373-1381,共9页
Hepatocellular carcinoma (HCC) is among most common terminal cancer types in the world. Primary etiological factors include cirrhosis, hepatitis, aflatoxin and alcohol. The current study was conducted to determine cyt... Hepatocellular carcinoma (HCC) is among most common terminal cancer types in the world. Primary etiological factors include cirrhosis, hepatitis, aflatoxin and alcohol. The current study was conducted to determine cytosolic erythrocyte carbonic anhydrase and catalase enzyme activities and levels of some trace elements. For this purpose, 40 patients with primary and metastatic hepatic cancer and 29 healthy volunteers enrolled to the study. Catalase and carbonic anhydrase enzyme activities and serum trace element levels were measured in patient and control groups. In the current study, serum copper, magnesium, manganese and zinc levels were lower in the primary and metastatic hepatic cancer group in comparison with the control group (P < 0.05). In contrast, serum iron, cobalt, cadmium and lead levels were higher in the patient relative to the control group (P < 0.05). In comparison with the control group, the catalase level was lower in primary and metastatic cancer group, while the carbonic anhydrase level was higher in the cancer group (P < 0.05). Changes in levels of trace elements and anti-oxidant enzymes may be the factors which influence the development and progression of liver cancer. The carbonic anhydrase enzyme can be a useful indicator in the diagnosis of cancer. However, this issue warrants further investigation. 展开更多
关键词 PRIMARY and METASTATIC Liver Cancer CATALASE Carbonic ANHYDRASE trace Element Heavy metal
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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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Review Study on the Accumulation and Release of Trace Metal Elements on Aluminum Containing Sediments in Drinking Water Distribution System 被引量:1
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作者 Xiaoni ZHANG Jinghua MENG +2 位作者 Li CHEN Huanhuan ZUO Wendong WANG 《Research and Application of Materials Science》 2020年第1期34-38,共5页
Accumulation and releasing of trace metal elements on aluminum containing sediments of inner drinking water pipe is discussed,as studied from five variations effecting:raw water quality,chemical reagents,solution pH a... Accumulation and releasing of trace metal elements on aluminum containing sediments of inner drinking water pipe is discussed,as studied from five variations effecting:raw water quality,chemical reagents,solution pH and drinking water flow condition.In order to decrease the release of trace metal elements,and to ensure the pipe operation and human safety,water quality adjustment is suggested to avoid aluminum containing sediments formation in drinking distribution system.The maximum amounts of accumulation of common trace metal elements are given.Future trends of development in this field are also proposed. 展开更多
关键词 drinking water distribution system aluminum containing sediments trace metal elements ACCUMULATION RELEASE
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Level of Contamination of Fishponds Water in Pesticide Residues and Metallic Trace Elements (Pb, Cd, As, Hg): Case of Fishponds of ZEPREGUHE (Daloa, Côte d’Ivoire)
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作者 Kacou Alain Paterne Dalogo Ano Guy Serge Ehouman +3 位作者 James Halbin Kouadio David Leonce Kouadio Edi Jean Frejus Ehui Karim Sory Traore 《Journal of Agricultural Chemistry and Environment》 CAS 2022年第4期307-317,共11页
Fishponds waters intended to satisfy the nutritional needs of the populations in terms of supply of fish resources are strongly and unfortunately exposed to the mobility and dispersion of metallic trace elements (TMEs... Fishponds waters intended to satisfy the nutritional needs of the populations in terms of supply of fish resources are strongly and unfortunately exposed to the mobility and dispersion of metallic trace elements (TMEs) or to the persistence in the environment and in the form of pesticide residues from human activities. The objective of this work is to evaluate, on the one hand, the levels of identified pesticide residues and, on the other hand, those of researched TMEs (lead, cadmium, mercury and arsenic) in the waters of ponds used for fish farming in Zépréguhé, a locality located 9 km from the town of Daloa in the centre-west of C&ocirc;te d’Ivoire. The dosage of the samples carried out by means of a gas chromatograph coupled to a mass spectrometer (GC/MS) made it possible to detect nine (9) pesticide molecules, including eight (8) organochlorines and a single molecule from the pyrethroid family, obtained from the detection limit of 0.006 μg/L and the quantification limit of 0.018 μg/L. The maximum average concentration was obtained with α-endosulfan for a content reaching 0.8038 μg/L and well above the maximum admissible concentration of 0.1 μg/L. The TMEs were quantified using an atomic absorption spectrophotometer (AAS). Arsenic is the most abundant metal with an average concentration of 9.497 μg/L. With the exception of lead, these measured levels are above the acceptable limit values for freshwater. This study showed that human activities such as the use of fertilisers and plant protection products in plantations, sand extraction and road traffic have a negative impact on the quality of the water in ponds used for fish breeding. 展开更多
关键词 Fishpond Water metallic trace elements Pesticide Residues Maximum Residue Levels
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Retention Factors for Trace Metal Elements in Solid Phase and Applicable Adsorption Models: Case of <i>Moringa oleifera</i>
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作者 Mariette Désirée Yehe Edwige Odoh +2 位作者 Patrick Grah Atheba Joel Cyriaque Dadje Gildas Komenan Gbassi 《Open Journal of Physical Chemistry》 2021年第3期182-195,共14页
<i><span style="font-family:;" "=""><i></i></span><i><span style="font-family:;" "="">Moringa oleifera</span></i>... <i><span style="font-family:;" "=""><i></i></span><i><span style="font-family:;" "="">Moringa oleifera</span></i><i><span style="font-family:;" "=""></span></i></i><span style="font-family:;" "=""> is an edible plant cultivated throughout the tropical belt. It belongs to the family Moringaceae and is one of its 14 known species. This paper presents a synthesis of the main factors responsible for the retention of trace metal elements (TMEs) by </span><span style="font-family:;" "=""><i></i></span><i><i><span style="font-family:;" "="">Moringa oleifera</span></i><i><span style="font-family:;" "=""></span></i></i><span style="font-family:;" "=""> seed powder, a natural adsorbent. The five main factors studied are metal concentration, solution pH, adsorbent particle size, adsorbent dose and adsorbent/adsorbate contact time. Through these factors, we present the optimal conditions for removal of these TMEs, as well as adsorption isotherm models appropriate for the conditions of retention of these metal cations by the adsorbent. The times of 20 min (GD) and 50 min (GND) are the equilibrium times obtained in our study. An optimal adsorbent mass (GD and GND powders) of 4.5 g was found. 20</span><span style="font-family:;" "="">%</span><span style="font-family:;" "=""> to 97% abatement is observed for average pH values between 6 and 8. The coefficients of determination (R2) obtained (0.972</span><span style="font-family:;" "="">,</span><span style="font-family:;" "=""> 0.963</span><span style="font-family:;" "="">,</span><span style="font-family:;" "=""> 0.991 and 0.799) during the isotherm experiments carried out at 20</span><span style="font-family:;" "="">°</span><span style="font-family:;" "="">C, 30</span><span style="font-family:;" "="">°</span><span style="font-family:;" "="">C, 40</span><span style="font-family:;" "="">°</span><span style="font-family:;" "="">C and 50</span><span style="font-family:;" "="">°</span><span style="font-family:;" "="">C are close to 1. Also, the separation factor (R<sub>L</sub>), an essential characteristic of the Langmuir isotherm whose values are between 0 and 1, attest to the applicability of the Langmuir isotherm model to fit the experimental data of copper adsorption by Moringa powders.</span><span style="font-family:;" "=""> In this paper, we are particularly interested in the following TMEs (Mn, Ni, Cr, Cu, Cd, Co, Pb, Fe, Zn, Ag).</span> 展开更多
关键词 Moringa oleifera ADSORPTION trace metal elements (tmes)
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Distribution of major and trace elements in surface sediments of Hangzhou Bay in China 被引量:5
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作者 LIU Shengfa LIU Yanguang +4 位作者 YANG Gang QIAO Shuqing LI Chaoxin ZHU Zhiwei SHI Xuefa 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2012年第4期89-100,共12页
The Inductively Coupled Plasma Optical Emission Spectrometer was used to analyze sediment samples collected from the Hangzhou Bay to determine major and trace elemental concentrations. Based on these concentrations, t... The Inductively Coupled Plasma Optical Emission Spectrometer was used to analyze sediment samples collected from the Hangzhou Bay to determine major and trace elemental concentrations. Based on these concentrations, the study area can be classified into three geochemical provinces. Province I covers the northern Hangzhou Bay area and contains high concentrations of A120~, Fe203, MgO, Na20, K20, MnO, Cr, Cu, Ni, Pb, V, Co and Zn. Province III is located in the western Hangzhou Bay, near the Qiantang River mouth, and contains high concentrations of SiO~, Na20, P205~ TiO2, Cr, Sr, Zr. Province II is located in the middle and eastern Hangzhou Bay, with the medium concentrations of major and trace elements. The results also demonstrate that the grain size is the dominating factor controlling the spatial variations of elemental concentrations, and the Changjiang River (Yangtze River) and Qiantang River sediments play an important role in the distribution of these elements. Anthropogenic impact on heavy metal concentrations (especially Cr, Sr and Zr) can be detected in the surface sediments near the Qiantang River mouth. 展开更多
关键词 Hangzhou Bay Changjiang River SEDIMENTS major and trace elements grain size heavy metals
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Bioleaching of trace elements and rare earth elements from coal fly ash 被引量:4
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作者 Stephen Park Yanna Liang 《International Journal of Coal Science & Technology》 EI 2019年第1期74-83,共10页
Coal fly ash originated from coal combustion has high concentrations of metals. If suitable leaching techniques are identified, then coal fly ash could serve as a useful source of valuable minerals including rare eart... Coal fly ash originated from coal combustion has high concentrations of metals. If suitable leaching techniques are identified, then coal fly ash could serve as a useful source of valuable minerals including rare earth elements (REEs). In this study, three microbial strains, Candida bombicola, Phanerochaete chrysosporium and Cryptococcus curvatus were tested on their performance of leaching trace elements and REEs from fly ash. Through comparing mineral loss and leaching efficiencies resulting from indirect leaching or use of the culture supernatant, C. bombicola was identified to be the best leading to the highest mineral loss and extracting efficiencies of trace elements and REEs among the three strains. The highest mineral loss observed from using the supernatant of this yeast strain was 59.7%. Among all trace elements, As and Mo had the highest leaching efficiency of 80.9% and 79.5%. respectively. The same leaching test led to 67.7% of Yb and 64.6% of Er dissolved from the ash. This study, thus, demonstrated that bioleaching is feasible for leaching metals out of fly ash. The C. bombicola strain deserves further investigation due to its robust actions on metal leaching. 展开更多
关键词 CRYPTOCOCCUS curvatus CANDIDA bombicola PHANEROCHAETE CHRYSOSPORIUM - Coal fly ash BIOLEACHING Rare earth elements trace metals
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Plasma Concentrations of Some Trace Element and Heavy Metals in Patients with Metastatic Colon Cancer 被引量:3
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作者 Ozgur Emre Halit Demir +6 位作者 Erkan Dogan Ramazan Esen Tugba Gur Canan Demir Edip Gonullu Nedim Turan Mehmet Fatih Ozbay 《Journal of Cancer Therapy》 2013年第6期1085-1090,共6页
Purpose: It is well known that trace elements and heavy metals play a significant role in human health and disease. These elements play an important role in different metabolic pathways of cells and tissues. Trace ele... Purpose: It is well known that trace elements and heavy metals play a significant role in human health and disease. These elements play an important role in different metabolic pathways of cells and tissues. Trace element deficiency or excess is implicated in the development or progression of some cancers. We present a study which investigates serum/ plasma levels of trace-heavy elements in metastatic colon cancer patients and healthy subjects. Methods: Blood samples were collected from 29 healthy subjects and 40 patients with metastatic colon cancer in Oncology Department of Medical School of Yuzuncu Yil University. In both groups, the serum levels of copper (Cu), magnesium (Mg), lead (Pb), chromium (Cr), zinc (Zn) selenium (Se), manganese (Mn), and cadmium (Cd) were determined. Results: Higher levels of Cu, Mg, Pb, Cr, Zn, Mn and Cd were seen in patients with metastatic colon cancer compared to healthy subjects and these findings were statistically significant (p 0.05). Se levels were noted to be lower in patients with colon cancer in comparison to healthy subjects and this finding was also statistically significant (p 0.05). Conclusions: According to our findings there was significant diffence in trace elements and heavy metals levels between healthy subjects and metastatic colon cancer patients. Therefore heavy metal and trace elements may have prognostic significance in complex disorders including colon cancer. However, further comprehensive studies are needed in order to advance our understanding of the relationship between heavy metal and trace elements and their role in cancers. 展开更多
关键词 Colon Cancer trace Element Heavy metal Essential Element
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Assessment of the Degree of Contamination by Metal Traces Element (Cd, Zn, Cu, Pb) in the Environment of an Open Landfill of a Large City Part One : A Human Population
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作者 Khadija Boulaajoul-Amrani Azzeddine Sedki Jean Musso 《Journal of Environmental Science and Engineering(B)》 2017年第3期144-150,共7页
The disposal of urban or hospital waste in open landfills is the easiest way to throw back of them without environmental concerns. MTEs (Metal Trace Elements) are the most toxic mineral elemems. This study evaluates... The disposal of urban or hospital waste in open landfills is the easiest way to throw back of them without environmental concerns. MTEs (Metal Trace Elements) are the most toxic mineral elemems. This study evaluates the impact of MTE on a neighboring human population or playing near a municipal dump. Two panels were composed of adult men and children (males under sixteen years old). Four trace metal elements were analyzed: copper, lead, cadmium and zinc. The site of the study was the municipal waste dump in Marrakech (Morocco). The results reveal abnormal concentrations of these MTEs in blood and hair of adults and children. 展开更多
关键词 Humans metal traces element contamination open landfill.
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Grain Size and Metallic Trace Element Contents in Sediments of Kemaman Coast, Terengganu, Malaysia, South China Sea
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作者 Nor Antonina Abdullah Noor Azhar Mohd Shazili +1 位作者 Rosnan Yaacob Kamaruzzaman Yunus 《Journal of Earth Science and Engineering》 2014年第2期80-87,共8页
A total of 43 sediment samples were collected at Kemaman coast, Terengganu, by using Smith Mclntyre grab. These sediments were analyzed to determine the grain size, sediment texture and metallic trace elements. Lazer ... A total of 43 sediment samples were collected at Kemaman coast, Terengganu, by using Smith Mclntyre grab. These sediments were analyzed to determine the grain size, sediment texture and metallic trace elements. Lazer diffraction method using PSA (particle size analyzer) was used to determine the grain size and sediment texture. Teflon bomb was used to digest the sediments for metallic trace elements concentration. Results showed that the study area was dominated with sand particles (60.5%) followed by loamy sand (20.9%), sandy clay (16.3%) and silt loam (2.3%). On the other hand, the average concentrations of each metallic trace elements were 0.12 pg/g for Cd; 36.6 lag/g for Cr; 9.51 pg/g for Cu; 11.6 ~tg/g for N: 41.5 ~tg/g for Zn and 29.3/ag/g for Pb. Based on the results, it was found out that coarse sediments showed lower levels of metallic trace elements and higher levels in fine sediments. In addition, enrichment factor was calculated to assess the pollution status of the study area. Based on the calculation, the enrichment of metallic trace elements ranked in the following order: Pb 〉 Cd 〉 Zn 〉 Cu 〉 Ni 〉 Cr. The significant enrichment of Pb and moderate enrichment of Cd and Zn indicated that there are anthropogenic inputs while the rest of the metals can be considered from natural sources although there are effects of anthropogenic inputs in some sampling location. 展开更多
关键词 Sediment Kemaman coast metallic trace elements.
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原子吸收光谱法测定苦瓜中微量金属元素的含量 被引量:1
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作者 胡庆兰 《湖北第二师范学院学报》 2024年第2期1-5,共5页
用微波消解法对苦瓜进行预处理,采用火焰原子吸收光谱法测定了苦瓜中钙、镁、铁、锌四种微量金属元素的含量。在最佳条件下测得苦瓜中各金属元素的含量分别为Ca:3843.50μg/g,Mg:2545.492μg/g,Fe:93.3415μg/g,Zn:77.685μg/g;RSD为0.1... 用微波消解法对苦瓜进行预处理,采用火焰原子吸收光谱法测定了苦瓜中钙、镁、铁、锌四种微量金属元素的含量。在最佳条件下测得苦瓜中各金属元素的含量分别为Ca:3843.50μg/g,Mg:2545.492μg/g,Fe:93.3415μg/g,Zn:77.685μg/g;RSD为0.19%~0.85%;检出限为0.0020μg·mL^(-1)~0.0703μg·mL^(-1);相关系数为0.9927~0.9997;加标回收率为94.60%~102.92%,此方法简单、快捷、经济、有效。 展开更多
关键词 苦瓜 微波消解法 微量金属元素 火焰原子吸收光谱法
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麋鹿被毛微量元素、重金属含量及对环境污染的监测作用
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作者 程志斌 白加德 +6 位作者 钟震宇 张宇晨 张树苗 张庆勋 单云芳 郭青云 张盼 《野生动物学报》 北大核心 2024年第1期35-42,共8页
哺乳动物被毛微量元素和重金属元素含量能够反映其生活状态和栖息地状况,是环境监测中重要的生物化学指示物。对北京南海子和浙江临安两地麋鹿(Elaphurus davidianus)种群被毛中的10种重金属和34种微量元素进行测定,以期探讨麋鹿被毛微... 哺乳动物被毛微量元素和重金属元素含量能够反映其生活状态和栖息地状况,是环境监测中重要的生物化学指示物。对北京南海子和浙江临安两地麋鹿(Elaphurus davidianus)种群被毛中的10种重金属和34种微量元素进行测定,以期探讨麋鹿被毛微量元素和重金属含量在栖息环境监测中的可行性。结果表明:除Re元素外,其余43种元素在麋鹿被毛中均被检出,统计分析表明Li、Be、Sc、V、Co、Ga、Rb、Ir、Mo、Cd、Cs、Ba、La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu、Tl、Bi、Th、U、Nb、Ta、Zr和Hf 34种元素为麋鹿被毛的特征元素;与北京南海子麋鹿种群相比,浙江临安麋鹿种群被毛中的微量元素Sr、In、Sb、W、Bi、U和重金属元素Zn、Cu、Cr、Pb、Cd含量更少,其余32种元素含量均高于北京南海子麋鹿种群;独立样本t检验分析表明,麋鹿被毛微量元素和重金属元素含量存在地域差异性,仅Cr(p=0.064)、Ni(p=0.769)、Mo(p=0.129)、Tl(p=0.065)、Zr(p=0.138)和Hf(p=0.057)6种元素差异不显著,其余37种元素差异均显著;北京南海子和浙江临安麋鹿种群的栖息环境和食物均未受到Zn、Cu、Cr、Pb、Cd、V、Co、Ni、Sb和Tl 10种重金属元素污染的威胁。研究表明,麋鹿被毛可作为栖息环境重金属污染的非损伤监测指示材料。 展开更多
关键词 麋鹿 被毛 微量元素 重金属 生物监测
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新疆阿尔泰可可托海矿区伟晶岩成因与矿化潜力研究:来自石英SEM-CL和微量元素的指示
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作者 曹冲 申萍 +3 位作者 冯浩轩 罗耀清 楚翔凯 任文斌 《岩石学报》 SCIE EI CAS CSCD 北大核心 2024年第3期889-906,共18页
新疆阿尔泰可可托海3号脉矿床是世界瞩目的伟晶岩型稀有金属Li-Be-Nb-Ta-Rb-Cs-Hf矿床。尽管前人对3号脉伟晶岩矿床已经进行了大量的研究工作,然而在伟晶岩稀有金属成矿潜力以及伟晶岩成因问题上仍存在一些争议。本文以发育在可可托海... 新疆阿尔泰可可托海3号脉矿床是世界瞩目的伟晶岩型稀有金属Li-Be-Nb-Ta-Rb-Cs-Hf矿床。尽管前人对3号脉伟晶岩矿床已经进行了大量的研究工作,然而在伟晶岩稀有金属成矿潜力以及伟晶岩成因问题上仍存在一些争议。本文以发育在可可托海矿区不同规模的伟晶岩脉以及淡色花岗岩为研究对象,利用石英SEM-CL和原位微量元素技术手段,查明各伟晶岩脉和花岗岩的稀有金属禀赋差异及成因联系。研究结果表明,石英的Li和Al含量可以用来指示伟晶岩的矿化潜力。与1号和2号伟晶岩脉相比,3号伟晶岩脉具有更宽的分异范围,以石英中Ge/Ti变化于1.83×10^(-6)~159×10^(-6)范围为特征,更高的Li含量,其中外侧带平均Li含量为39×10^(-6),因而成矿潜力最大。此外,证实了白云母钠长花岗岩为矿化花岗岩,其微量元素组成和演化程度与3号脉伟晶岩外侧带相当,而白云母碱长花岗岩为贫矿花岗岩。更重要的是,本文利用各伟晶岩结构分带内的石英中Ge/Ti-Ge以及Ge/Ti-Al/Ti图解,确定了各伟晶岩脉具有相似的演化趋势,指示它们可能源于相同的花岗岩母岩。与世界上典型的RMG(花岗岩浆演化后残余熔浆结晶)和DPA(直接深部地壳熔融)成因的伟晶岩相比,可可托海矿区含矿伟晶岩和花岗岩中石英微量元素与RMG成因伟晶岩存在地球化学亲和性,这指示它们来源于花岗质岩浆的残留熔浆。 展开更多
关键词 可可托海稀有金属伟晶岩型矿床 石英微量元素 成矿潜力 岩石成因
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沉积矿床中重要(变价)金属元素与古海洋环境关系综述--以新元古代-早古生代扬子板块周缘为例 被引量:1
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作者 张岩 方维萱 +7 位作者 徐林刚 陈文 张志炳 叶会寿 刘丽红 王文浩 赵亮亮 吴皓然 《地质论评》 CAS CSCD 北大核心 2024年第2期679-704,共26页
对氧化—还原敏感元素和生命必需元素地球化学性质和相关沉积矿产形成机制及其时空分布特征的分析、总结和归纳,有助于对古海洋环境演化与相关沉积矿产形成关系的深入认识,这对沉积矿床学理论的发展具有重要意义。新元古代南华纪—早古... 对氧化—还原敏感元素和生命必需元素地球化学性质和相关沉积矿产形成机制及其时空分布特征的分析、总结和归纳,有助于对古海洋环境演化与相关沉积矿产形成关系的深入认识,这对沉积矿床学理论的发展具有重要意义。新元古代南华纪—早古生代早志留世,扬子板块周缘黑色岩系中依次沉积了举世瞩目的南华纪锰矿、震旦纪—早寒武世沉积磷块岩、早寒武世重晶石矿、镍—钼—钴多金属矿、钒矿和早志留世铀矿的完整沉积矿床系列,不同时代地层、同一时代不同沉积环境地层赋存不同类型的沉积矿产,有必要对其成矿机理进行系统研究、总结和归纳。笔者等在对氧化—还原敏感金属元素、生命必需元素和海底热液元素等元素地球化学性质综述的基础上,兼论了它们在结合黄铁矿矿物学对氧化—还原环境、生物生产力和盆地限制性分析方面具体作用;进一步结合新元古代—早古生代扬子板块古环境演化特征,对扬子板块周缘特定时代中特定沉积矿产的分布、成因机理进行分析、总结和归纳;最终得出扬子板块周缘相关沉积矿产,是在全球氧化事件、冰期—间冰期、Rodina大陆裂解大背景下,海洋中成矿金属元素得到长期积累,在特定时代区域性海水—海底热液—生物作用(根据不同矿种各有侧重)影响下,在相关重要元素地球化学性质的控制下、局部区域特殊氧化—还原环境的控制下形成的特定矿产的初步认识。最后,结合相关沉积矿床研究中存在的问题,提出下一步解决方案与展望。 展开更多
关键词 氧化—还原敏感金属元素 生命必需元素 氧化—还原环境判别方法 扬子板块周缘 南华纪—早志留世 沉积矿产
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燕山北部山地华北落叶松人工林大气湿沉降的养分输入研究
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作者 田贺 张梦悦 +5 位作者 李校 卢金平 奚悦 朱剑兴 许中旗 贾彦龙 《河北农业大学学报》 CAS CSCD 北大核心 2024年第4期36-44,共9页
为了解燕山北部山地森林全年降水中养分的输入情况,本研究以燕山北部山地华北落叶松(Larix principisrupprechtii)人工林为研究对象,对2020年8月—2021年7月该地区的降水进行收集,并测定降水中大量元素、微量元素和重金属元素的含量,分... 为了解燕山北部山地森林全年降水中养分的输入情况,本研究以燕山北部山地华北落叶松(Larix principisrupprechtii)人工林为研究对象,对2020年8月—2021年7月该地区的降水进行收集,并测定降水中大量元素、微量元素和重金属元素的含量,分析了各元素沉降的季节动态和元素间的相关性。结果表明:(1)大量元素沉降量整体表现为夏季>春季>秋季>冬季,其中氮、磷、钾、硫元素的总沉降量分别为9.87、0.04、2.28、240.59 kg/hm^(2)。(2)微量元素中大部分元素的沉降量同样表现为夏季最高;氯、铁、锰、锌、铜元素的沉降总量值分别为6582.39、12.76、6.26、30.32、3.91 g/hm^(2);硼元素的沉降量为春季最高,沉降总量值为68.18 g/hm^(2)。(3)重金属元素中铬、锂、镍3种元素的沉降量为夏季最高,总沉降量分别为2.30、2.42、1.64 g/hm^(2);镉、钴2种元素的沉降量为秋季最高,总沉降量分别为0.43、0.14 g/hm^(2);铅元素的沉降量为冬季最高,总沉降量为1.41 g/hm^(2)。(4)元素相关性分析结果显示,总磷(TP)、总氮(TN)与钾,氯元素、锌元素与锰元素都呈现正相关关系,所以大量元素中的氮、磷、钾,微量元素中的锰、锌、氯可能有着相同的来源或相似的迁移规律。本研究初步明确了燕山北部山地森林全年降水中的养分输入量,对于认识该地区森林的养分循环有重要意义。 展开更多
关键词 大气湿沉降 大量元素 微量元素 重金属元素 季节动态
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不同产地连翘质量的研究现状分析
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作者 杨允 王园 +6 位作者 王晓婷 王春柳 刘洋 孙婷婷 房敏峰 龙凯花 张红 《西北药学杂志》 CAS 2024年第3期1-9,共9页
目的总结不同产地连翘质量控制的研究现状。方法通过收集连翘中主要化学成分的研究文献资料,对不同产地连翘中主要化学成分(总挥发油、连翘酯苷A、连翘酯苷B、连翘苷和微量元素钠、锰、锌、铁、镁、钾、钙、铬、锗、硒及重金属铅、镉、... 目的总结不同产地连翘质量控制的研究现状。方法通过收集连翘中主要化学成分的研究文献资料,对不同产地连翘中主要化学成分(总挥发油、连翘酯苷A、连翘酯苷B、连翘苷和微量元素钠、锰、锌、铁、镁、钾、钙、铬、锗、硒及重金属铅、镉、砷、汞、铜)的含量研究结果进行数据收集和比较。结果由统计分析结果可知,陕西、湖北、安徽的样本挥发油质量分数均值约为1.7%,为最高;河南、陕西和山西的连翘酯苷A含量排名靠前,分别为5.47%、4.90%、4.83%;山西连翘中的连翘酯苷B样本量最高且含量均值高于其他产地;山西连翘微量元素优势较大,山西运城、太原、临汾、晋中产地的连翘中的Mn、Fe、Mg、K、Ca、Cr、Ge、Se质量分数居于前列,Na、Zn分别是河南三门峡、河北邯郸产地较优;各产地连翘的重金属含量均未超标。结论山西、河南、陕西、河北作为连翘的主要产区,多种化学成分的质量分数普遍高于其他产区,品质更为优良。本文为开展不同产地连翘的共性和个性特征研究提供了数据支撑,为各产地连翘的质量控制提供了参考。 展开更多
关键词 连翘 挥发油 连翘酯苷A 连翘苷 微量元素 重金属
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菊花茶中重金属和微量元素溶出特性研究
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作者 唐宁 杨永贵 +4 位作者 熊嘉成 高娜 胡静 赵首萍 叶雪珠 《中国无机分析化学》 CAS 北大核心 2024年第7期995-1005,共11页
为了探究菊花茶和茶汤中重金属及微量元素含量,指导菊花茶的饮用,对浙江主要菊花茶品种皇菊和金丝皇菊的重金属和微量元素含量及其溶出特性进行了分析。通过电感耦合等离子体质谱法(ICP-MS)和电感耦合等离子体发射光谱(ICP-OES)测定Cd... 为了探究菊花茶和茶汤中重金属及微量元素含量,指导菊花茶的饮用,对浙江主要菊花茶品种皇菊和金丝皇菊的重金属和微量元素含量及其溶出特性进行了分析。通过电感耦合等离子体质谱法(ICP-MS)和电感耦合等离子体发射光谱(ICP-OES)测定Cd、Cr、Cu、Pb、Zn、Ni、As等7种重金属和K、Na、Ca、Mg、Se、Fe和Mn等7种微量元素的含量,并参照传统泡茶方式对不同浸泡时间及不同浸泡次数条件下的皇菊和金丝皇菊中重金属和微量元素的溶出特性进行研究。结果发现,两种菊花中Cd含量均超标,但茶汤中的Cd与其他重金属符合生活饮用水标准,随着浸泡时间延长,菊花中重金属和微量元素的溶出率逐渐增加,Cd的总溶出率仅9.9%~11.8%,Cr、Pb的总溶出率也在10%以下,但Cu、Zn、Ni、As溶出率较高,在45.0%~71.6%,微量元素的溶出率在1.7%~84.0%,其中K、Na、Se元素的溶出率较高,最高分别达到了84.0%、72.9%、78.0%;随着浸泡次数增加,菊花中重金属和微量元素的溶出率逐渐降低,在第一次浸泡后,菊花中Cd、Cr、Pb的溶出率较低,分别在0.3%~8.0%,Cd、Cr、Pb的初次溶出量占溶出总量50%~100%,Cu、Zn、Ni、As在第一次浸泡后,溶出量占总量的28%~63%,第一次浸泡后,菊花中的K和Se的溶出率较高,达到30.6%~65.8%,Na、Ca、Mg、Mn的溶出率在5.8%~29.4%。微量元素第一次浸泡溶出量占溶出总量的41%~100%。两种菊花中,金丝皇菊第一次浸泡溶出的重金属和微量元素比例均较高。通过延长浸泡时间可增加茶汤中重金属和微量元素的溶出,弃去初泡水的方式,虽然去除了过半含量的重金属,但同时也损失了大量微量元素,建议泡茶时延长浸泡时间。 展开更多
关键词 皇菊 金丝皇菊 重金属 微量元素 溶出特性
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不同蛋白原料中矿物质元素含量分析
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作者 王威 门晓冬 +4 位作者 薛敏 刘璐 范志影 包郁明 谷旭 《中国饲料》 北大核心 2024年第11期129-136,共8页
本试验旨在研究不同蛋白原料中常量元素、微量元素、重金属元素等26种元素的含量及分布规律,分析其含量差异可能成因,为不同蛋白原料科学利用提供数据依据。本实验利用电感耦合等离子体质谱(ICP-MS)技术,系统分析了鸡肉粉、鱼粉、花生... 本试验旨在研究不同蛋白原料中常量元素、微量元素、重金属元素等26种元素的含量及分布规律,分析其含量差异可能成因,为不同蛋白原料科学利用提供数据依据。本实验利用电感耦合等离子体质谱(ICP-MS)技术,系统分析了鸡肉粉、鱼粉、花生浓缩蛋白、大豆浓缩蛋白、棉籽蛋白、菌体蛋白、藻粉和昆虫粉等8种15批次的蛋白原料中元素组成及分布规律。结果表明,所有蛋白原料均含有供试矿物质元素,不同种类的蛋白原料矿物质元素含量差异较大(P<0.05);某些元素在同种不同来源的原料中含量水平差异显著(P<0.05);存在蛋白原料中单一元素含量明显高于其他原料的现象(P<0.05)。通过对数据结果的分析有利于推广应用新型蛋白质饲料原料,促进我国养殖业的可持续发展。 展开更多
关键词 蛋白原料 常量元素 微量元素 重金属元素 电感耦合等离子体质谱(ICP-MS)
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盐酸超声提取-高分辨电感耦合等离子体质谱法测定食用植物油中11种微量金属元素
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作者 李胜 李锦才 +3 位作者 陈晓燕 陈树娣 吴蓝洁 杨心怡 《理化检验(化学分册)》 CAS CSCD 北大核心 2024年第7期718-724,共7页
提出了盐酸超声提取-高分辨电感耦合等离子体质谱法(HR-ICP-MS)快速测定食用植物油中铝、钡、镉、铜、铁、镁、锰、镍、铅、钒、锌等微量金属元素的方法。取2.0 g食用植物油样品,置于50 mL塑料离心管中,加入800μL ICP溶剂油,于旋涡混... 提出了盐酸超声提取-高分辨电感耦合等离子体质谱法(HR-ICP-MS)快速测定食用植物油中铝、钡、镉、铜、铁、镁、锰、镍、铅、钒、锌等微量金属元素的方法。取2.0 g食用植物油样品,置于50 mL塑料离心管中,加入800μL ICP溶剂油,于旋涡混匀器上充分混匀,加入10 mL 2.0 mol·L^(-1)盐酸溶液,于70℃超声30 min,冷却。以转速10000 r·min^(-1)离心5 min,在水相与有机相分离后,收集水相,采用HR-ICP-MS测定其中11种元素含量,待测同位素^(51)V、^(56)Fe、^(27)Al、^(63)Cu、^(24)Mg、^(55)Mn、^(60)Ni、^(66)Zn选择中分辨率模式,而^(137)Ba、^(111)Cd和^(208)Pb选择低分辨率模式。结果表明:11种元素的质量浓度在100μg·L^(-1)以内与对应的信号强度呈线性关系,检出限(3s)为0.012~0.173μg·L^(-1);按照标准加入法对食用植物油进行回收试验,回收率为86.9%~107%,测定值的相对标准偏差(n=7)为1.1%~4.9%;方法用于分析3种植物油样品,本方法测定值与标准方法的测定值基本一致。 展开更多
关键词 盐酸超声提取 高分辨电感耦合等离子体质谱法 食用植物油 微量金属元素
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