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Trace Element Concentrations in the Sera of Pregnant Women in Kisangani, Democratic Republic of Congo
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作者 Likilo Osundja Jérémie Komanda Likwekwe Emmanuel +3 位作者 Tshodi Bulanda Arsène Juakali Sihalikyolo Jean-Jeannot Buhendwa Mirindi Victor Katenga Bosunga Gédéon 《Journal of Biosciences and Medicines》 2025年第2期218-229,共12页
Introduction: During pregnancy, the increased demand for all the nutrients required for the development of the foetus means that the maternal stock of trace elements and minerals may become unbalanced if dietary intak... Introduction: During pregnancy, the increased demand for all the nutrients required for the development of the foetus means that the maternal stock of trace elements and minerals may become unbalanced if dietary intake fails to compensate. The aim of this research is to determine the status of trace elements (calcium, copper, magnesium, selenium and zinc) in pregnant women in the city of Kisangani. Methods: We carried out an analytical cross-sectional study of non-pregnant and pregnant women living in Kisangani, from 05 October 2023 to 05 January 2024. Concentrations of trace elements in sera were analysed using an inductively coupled plasma mass spectrophotometer (ICP-MS Agilent 7700X). Statistical analysis of the data was performed using R software version 4.3.0. Results: The mean age was 26.3 ± 6.7 years;the mean copper and magnesium levels in the serum of pregnant women were 12.58 ± 1.13 micromol/l and 1.03 ± 1.03 mmol/l respectively. The medians for calcium and zinc were 1.49 mmol/l and 8.42 micromol/l. The selenium mode was 0.41 micromol/l. Variations in trace element levels in sera of pregnant women were 0.94 - 2.22 mmol/l for calcium;0.31 - 0.78 micromol/l for selenium;and 7.29 - 12.72 micromol/l for zinc;11.04 - 14.99 micromol/l for copper, and 0.082 - 1.05 mmol/l for magnesium. Conclusion: Serum trace element concentrations in pregnant women were lower than those observed in non-pregnant women. Trace element reserves in pregnant women depended on their nutrient status prior to pregnancy, hence, there was an urgent need for trace element balance prior to pregnancy. 展开更多
关键词 trace element Zinc Copper SELENIUM CALCIUM Magnesium Pregnant Woman SERUM Kisangani
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Magmatic to Hydrothermal Evolution of Bianjiadayuan Ag-Pb-Zn-Sn Deposit,Northeast China:A Quartz Texture and Trace Elements Study
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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
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Effects of combined preconception and prenatal myo-inositol, probiotics, and trace element supplementation on the outcomes of depressed mothers
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作者 Shu-Fang Qi Hong-Xia Sun Jie Zhao 《World Journal of Psychiatry》 2025年第7期91-102,共12页
BACKGROUND Perinatal depression affects 10%-20%of pregnant women and subsequently influences maternal health and fetal development.Concerns over the safety of antidepressants during pregnancy have prompted the explora... BACKGROUND Perinatal depression affects 10%-20%of pregnant women and subsequently influences maternal health and fetal development.Concerns over the safety of antidepressants during pregnancy have prompted the exploration of nutritional interventions as adjunct therapies.This study evaluated the impact of combining preconception and prenatal supplementation with myo-inositol,probiotics,and trace elements on mood,quality of life,and fetal development in depressed mothers.This retrospective cohort study included 314 pregnant women who were diag-nosed with mild to moderate depression,as determined by a Zung self-rating depression scale score of less than 69.The participants were divided into an intervention group(n=161)receiving myo-inositol,probiotics,and trace elements and a control group(n=153)without supplementation.Supplementation comm-enced 3 months before conception and continued through pregnancy.Psychiatric symptoms and quality of life were evaluated using the positive and negative affect schedule-now,state-trait anxiety inventory,Patient Health Ques-tionnaire-8,and World Health Organization Quality of life Assessment:Brief Version scales preconception and postpartum.Fetal development metrics were assessed via ultrasound,and neonatal outcomes were recorded.RESULTS The intervention group presented significant reductions in gestational diabetes mellitus(13.04%vs 23.53%,P=0.016)and gestational hypertension(3.73%vs 9.15%,P=0.049).Higher levels of inositol,iron,zinc,and probiotics were observed near term in the intervention group.Postpartum mood assessments indicated lower anxiety and depression scores for the intervention group,with significant improvements in the positive and negative affect schedule-now(P=0.002),trait anxiety(P=0.002),and Patient Health Questionnaire-8(P=0.018)scores.The World Health Organization Quality of life Assessment:Brief Version scores improved in the psychological(P=0.041)and environmental(P=0.009)domains postpartum.Fetal biparietal diameter and femoral length were greater in the intervention group alongside better neonatal body length and reduced neonatal unit admissions(2.48%vs 7.84%,P=0.031).CONCLUSION Combined supplementation with myo-inositol,probiotics,and trace elements from preconception through pregnancy may reduce pregnancy-related complications,enhance mood and quality of life,and improve fetal growth metrics. 展开更多
关键词 nutritional interventions retrospective cohort study perinatal depression trace elements PRECONCEPTION PRENATAL preconception prenatal supplementation adjunct therapiesthis
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Assessment of trace elements distribution and sources from snowpits in the Lambert Glacier region,coastal East Antarctica
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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
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Miocene Pb-Zn Mineralization in the Eastern Gangdese Metallogenic Belt:Evidence from in situ Rb-Sr Dating of Mica and Trace Element Geochemistry of Sphalerite
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作者 ZHAO Xiaoyan YANG Zhusen +2 位作者 LIU Chang DONG Yanrui SHI Haiyan 《Acta Geologica Sinica(English Edition)》 2025年第3期806-821,共16页
Four Pb-Zn deposits,namely Bangpu(BP),Digei(DG),Nabuding(NB)and Cuoga(CG),are located within a 20 km distance of each other in the Gangdese porphyry copper belt(GPCB).The age and nature of the Pb-Zn mineralization,esp... Four Pb-Zn deposits,namely Bangpu(BP),Digei(DG),Nabuding(NB)and Cuoga(CG),are located within a 20 km distance of each other in the Gangdese porphyry copper belt(GPCB).The age and nature of the Pb-Zn mineralization,especially its relationship to magmatism,remain uncertain.In order to address this issue,mica from the four deposits was selected for in situ Rb-Sr dating,with sphalerite additionally being selected for in situ trace element analysis.Detailed geological research has revealed that the BP and NB deposits are primarily skarn-type Pb-Zn mineralization,while DG and CG are associated with magmatic hydrothermal breccia and are characterized by banded-type mineralization.The Rb-Sr isochron ages of syn-mineralization muscovite at the BP and CG deposits are 11±6 Ma and 19.7±0.7 Ma respectively.Fe,Cd,In,Mn and Sn occur as lattice substitutions in sphalerite from the four deposits.Cu exists as microinclusions in BP,but occurs isomorphically in the DG,NB and CG deposits.The formation temperatures of the four deposits,as calculated from sphalerite geothermometry,range from approximately 200℃to 300℃,indicating that they belong to medium temperature deposits.BP and NB are classified as skarn Pb-Zn deposits,while DG and CG are categorized as hydrothermal filled Pb-Zn deposits.These results suggest that,in addition to porphyry Cu mineralization,the GPCB also contains significant Miocene Pb-Zn mineralization. 展开更多
关键词 in situ Rb-Sr dating trace elements SPHALERITE Pb-Zn deposit Gangdese porphyry copper belt
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Trace Elements and Tumor: Research Progress
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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
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Multiple-stage W mineralization in the Guanfang W deposit,southeastern Yunnan Province,China:Insights from scheelite in-situ trace elemental and Sr isotopic analyses
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作者 Bin Sun Yi Liu +4 位作者 Zhigang Kong Xuelong Liu Xiaojun Jiang Chao Li Wenchang Li 《Acta Geochimica》 2025年第1期112-127,共16页
The Guanfang large-scale W deposit is located in the W polymetallic ore concentration area of Bozhushan in southeastern Yunnan,China.Despite extensive research,the fluid evolution process of the deposit remains ambigu... The Guanfang large-scale W deposit is located in the W polymetallic ore concentration area of Bozhushan in southeastern Yunnan,China.Despite extensive research,the fluid evolution process of the deposit remains ambiguous,leading to controversy regarding its genesis.This study conducted a detailed field geological survey,with systematic sampling of the KT6 orebody,to delineate mineralization stages.Fine mineralogy work,including the use of CL images of scheelite,in-situ LA-ICP-MS trace elements,and Sr isotopes,was carried out on diff erent generations of scheelite formed in various stages.The findings identified the evolution of fluids in the mineralization process,shedding light on the genesis of the deposit.The study revealed four mineralization stages at the Guanfang W deposit:prograde skarn stage,retrograde skarn stage,quartz-sulfide stage,and carbonate-fluorite stage.Diff erent generations of scheelite(Sch I,Sch II,Sch III)were observed in the first three stages,displaying distinct chondrite-normalized REE patterns.The REE of Sch I mainly substituted into the Ca site by REE^(3+)+□_(Ca),and there may be a similar substitution of Nb for REE,whereas it is not the main substitution method.The REE of Sch II mainly enter the scheelite lattice in the form of REE 3++Na+,and there may be a substitution of Nb for REE isomorphism.In the early stage,The REE of Sch III was mainly replaced by Nb for REE isomorphism,while in the later stage,the replacement mode of REE^(3+)+□_(Ca)coexisted with it.The Mo content in scheelite,along with the corresponding Eu anomalies in both scheelite and garnet,collectively imply that the ore-forming fluids during various mineralization stages were predominantly oxidizing,with only slight reducibility observed in Sch II.The in-situ Sr isotope ratios of scheelite concentrates ranged from 0.7093 to 0.7153,resembling those of the Bozhushan granite,indicating a relationship between W mineralization and granite.In addition,the Y/Ho ratios of scheelite from various mineralization stages exhibit a narrow range(19-31),with a pronounced correlation between the contents of Y and Ho and a similar trend in their variation.This consistency suggests that the Guanfang deposit has undergone a uniform or comparable evolutionary process,implying a stable ore-forming fluid across diff erent mineralization stages. 展开更多
关键词 Guanfang W deposit trace elements of scheelite In-situ Sr isotopes Southeast Yunnan
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Wavy Distribution of Trace Elements in Phytolacca Samples from Different Areas 被引量:4
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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
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Determination of the Trace Element Contents in Plants Using Atomic Absorption Spectrophotometer 被引量:37
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作者 高淑云 《Agricultural Science & Technology》 CAS 2008年第2期6-9,共4页
The aim of the study is to investigate the contents of trace element Se, Cd, Pb in three plants including burdock, ginkgol and garlic via graphite furnace atomic absorption and standard addition method. The results sh... The aim of the study is to investigate the contents of trace element Se, Cd, Pb in three plants including burdock, ginkgol and garlic via graphite furnace atomic absorption and standard addition method. The results show that Se in burdock stem, skin and leaf are 32.40, 48.63, 38.10 μg/g, respectively; Cd in burdock stem, skin and leaf are 0. 160 0, 0. 300 0, 0. 140 0 μg/g, respectively; Cd in burdock stem, skin and leaf are 2. 020, 3. 960, 2. 410 μg/g, respectively. In the ginkgo and ginko leaf, Se contents are 17.63 and 16.91 μg/g, respectively ; for Cd are 0. 181 0 and 0.2020μg/g, respectively ; for Pb are 3. 572 and 4. 021 μg/g, respectively. In garlic, Se, Cd and Pb are 73. 900 0, 6. 900 0 and 0. 390 0, respectively. All the standard deviations of measured results are below 2.3%, recovery rate are from 99% to 101%. 展开更多
关键词 trace elements GFT AAS BURDOCK GINKGO GARLIC
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Effect of trace elements on growth of Pinus tabulaeformis seedling 被引量:7
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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
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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
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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
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Experiment of Coal Leaching and Study of the Separation of Trace Elements 被引量:6
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作者 LIU Guijian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第2期386-390,共5页
Leaching is an important way of separation of trace elements from coal. Based on leaching experiments, the content of trace elements separated out from coal is related to their existing state and content in coal, the ... Leaching is an important way of separation of trace elements from coal. Based on leaching experiments, the content of trace elements separated out from coal is related to their existing state and content in coal, the duration of leaching process, temperature of leaching liquor and its acidity and basicity. The higher the temperature of leaching liquor and the longer the leaching time, the higher the contents of separated trace elements will be. In the course of leaching, the pH values of leaching liquors change and different trace elements are affected differently by the pH values. 展开更多
关键词 Leaching experiment trace elements influence factors separation of trace element
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Study on the Major and Trace Elements in Soil of Yunnan Farmland
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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
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Clinical and experimental study on gastric mucosal Pathology DNA cAMP and trace elements of pixu patients
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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
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Study on Trace Elements in Rehmannia glutinosa Libosch. by Principal Component Analysis and Clustering Analysis
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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
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A trace element perspective on the source of ocean island basalts(OIB)and fate of subducted ocean crust(SOC)and mantle lithosphere(SML) 被引量:3
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作者 Yaoling Niu Marjorie Wilson +1 位作者 Emma R.Humphreys Michael J.O’Hara 《Episodes》 2012年第2期310-327,共18页
We analyze the first-order observations,basic concepts and explicit/implicit assumptions built into the three major hypotheses for the enriched component(s)in the source of ocean island basalts(OIB)in terms of incompa... We analyze the first-order observations,basic concepts and explicit/implicit assumptions built into the three major hypotheses for the enriched component(s)in the source of ocean island basalts(OIB)in terms of incompatible trace elements:(1)subducted ocean crust(SOC),(2)subducted continental sediments,and(3)mantle metasomatism. 展开更多
关键词 mantle metasomatism ocean island basalts oib trace elements trace elements subducted ocean crust soc subducted sedimentsand mantle metasomatism ocean island basalts subducted continental sediments subducted ocean crust
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Determination of Trace Elements in Potatoes by Flame Atomic Absorption Spectrometry
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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
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Different Carbon Fractions in Soils and Their Relationship with Trace Elements Content
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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.
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Effect of Trace Elements in Seed Coating Agent on Peanut Growth 被引量:1
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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
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Trace Elements and Rare Earth Elements of Sulfide Minerals in the Tianqiao Pb-Zn Ore Deposit,Guizhou Province,China 被引量:39
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作者 ZHOU Jiaxi HUANG Zhilong +3 位作者 ZHOU Guofu LI Xiaobiao DING Wei BAO Guangping 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第1期189-199,共11页
Trace elements and rare earth elements(REE) of the sulfide minerals were determined by inductively-coupled plasma mass spectrometry.The results indicate that V,Cu,Sn,Ga,Cd,In,and Se are concentrated in sphalerite,Sb... Trace elements and rare earth elements(REE) of the sulfide minerals were determined by inductively-coupled plasma mass spectrometry.The results indicate that V,Cu,Sn,Ga,Cd,In,and Se are concentrated in sphalerite,Sb,As,Ge,and Tl are concentrated in galena,and almost all trace elements in pyrite are low.The Ga and Cd contents in the light-yellow sphalerites are higher than that in the brown and the black sphalerites.The contents of Ge,Tl,In,and Se in brown sphalerites are higher than that in light-yellow sphalerites and black sphalerites.It shows that REE concentrations are higher in pyrite than in sphalerite,and galena.In sphalerites,the REE concentration decreases from light-yellow sphalerites,brown sphalerites,to black sphalerites.The ratios of Ga/In are more than 10, and Co/Ni are less than 1 in the studied sphalerites and pyrites,respectively,indicating that the genesis of the Tianqiao Pb-Zn ore deposit might belong to sedimentary-reformed genesis associated with hydrothermal genesis.The relationship between LnGa and LnIn in sphalerite,and between LnBi and LnSb in galena,indicates that the Tianqiao Pb-Zn ore deposit might belong to sedimentary-reformed genesis.Based on the chondrite-normalized REE patterns,δEu is a negative anomaly(0.13-0.88),andδCe does not show obvious anomaly(0.88-1.31);all the samples have low total REE concentrations(〈3 ppm) and a wide range of light rare earth element/high rare earth element ratios(1.12-12.35).These results indicate that the ore-forming fluids occur under a reducing environment.Comparison REE compositions and parameters of sphalerites,galenas,pyrites,ores,altered dolostone rocks,strata carbonates,and the pyrite from Lower Carboniferous Datang Formation showed that the ore-forming fluids might come from polycomponent systems,that is,different chronostratigraphic units could make an important contribution to the ore-forming fluids.Combined with the tectonic setting and previous isotopic geochemistry evidence,we conclude that the ore-deposit genesis is hydrothermal,sedimentary reformed,with multisources characteristics of ore-forming fluids. 展开更多
关键词 trace element rare earth element SPHALERITE GALENA pyrite deposit genesis Tianqiao PbZn ore deposit
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