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Effects of Different Pretreatment Methods on Determination of Microelements in Feed 被引量:2
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作者 葛亚明 宁红梅 +4 位作者 李敬玺 刘俊伟 安志兴 魏继涛 侯向红 《Animal Husbandry and Feed Science》 CAS 2009年第3期15-18,共4页
[ Objective] To study the effects of different pretreatment methods on determination of microelement in feed and thus find the best pre treatment method for each microetement, t Method] The samples (concentrated feed... [ Objective] To study the effects of different pretreatment methods on determination of microelement in feed and thus find the best pre treatment method for each microetement, t Method] The samples (concentrated feeding stuff and fodder) were pretreated through throe methods, that is, dry incineration method, HNOs HCIO, wetdecomposition method and microwave digestion method. Then the content of seven kinds of mi croelement (AI, Ca, Cu, Fe, Mn, Se and Zn) was determined by inductively coupled plasma atomic emission spectrometer (ICPAES). I Result] These three methods were all suitable for the determination of Cu, Mn and Zn in concentrated feeding stuff and the determination of Cu and Ca in fodder. The content of Cu and Ca was higher in fodder detected by HNO3 HCIO, wetdecomposition method. The microwave digestion method was suitable for the determination of AI and Ca in concentrated feeding stuff and the determination of AI, Fe, Mn and Zn in fodder. The dry incinera tion method was fit for the determination of Fe in concentrated feeding stuff. [ Condusionl The content of different microelements should be deter mined after the feed is treated with different Ioretreatment methods. 展开更多
关键词 Pretreatment methods Determination of microelements Inductively coupled plasma atomic emission spectrometry
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Primary Speciation Analysis on 6 Kinds of Microelements in Glycyrrhiza uralensis Fisch. 被引量:1
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作者 梁新华 李梦菊 +1 位作者 王俊 郑彩霞 《Agricultural Science & Technology》 CAS 2010年第1期96-98,146,共4页
[Objective]The aim was to analyze the primary speciation of 6 microelements in Glycyrrhiza uralensis Fisch. and provide theoretical basis for explaining pharmacodynamic principle of liquorice and discussing quality co... [Objective]The aim was to analyze the primary speciation of 6 microelements in Glycyrrhiza uralensis Fisch. and provide theoretical basis for explaining pharmacodynamic principle of liquorice and discussing quality control of liquorice planting. [Method]The 6 elements Cu,Zn,Ca,Fe,Mg and Mn in roots of G.uralensis were extracted based on traditional decoction method and were separated into water-soluble state and suspension state by micro porous filtering film. The elements in water-soluble state were detected by flame atomic adsorption spectrophotometry (FAAS). [Result]The results showed that extractive rates of the elements were in the range of 1.71%-60.06%,and immerse-residue ratio in 0.018 3-1.682 0; the results also indicated that the immerse-residue ratio of Zn was biggest (1.68),Zn played an important medical role and might be considered as the best characteristic element in G.uralensis; the recoveries of the elements were ranged from 95.72% to 103.15% and relative standard deviations (RSD) were less than 2.38%. [Conclusion]Because of its high accuracy,FAAS method is feasible for analyzing primary speciation of microelements in G.uralensis. 展开更多
关键词 Glycyrrhiza uralensis Fisch. Microelement Flame atomic adsorption sepctrophotometry (FAAS) Primary speciation analysis
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Effects of Reducing Mn^(2+),Cu^(2+) and Zn^(2+) Concentrations in Nutrient Solution on SOD Activity in Grafted Cucumber Seedling Leaves Under Cold Stress
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作者 李涛 高俊杰 于贤昌 《Agricultural Science & Technology》 CAS 2011年第11期1625-1627,1679,共4页
[Objective] The research aimed to study the effects of reducing the concentrations of Mn2+, Cu2+ or Zn2+ in nutrient solution on the contents of Mn, Cu and Zn of grafted cucumber leaves as well as on the SOD and is... [Objective] The research aimed to study the effects of reducing the concentrations of Mn2+, Cu2+ or Zn2+ in nutrient solution on the contents of Mn, Cu and Zn of grafted cucumber leaves as well as on the SOD and isozymes activities and the rate of electrolytic leakage under cold stress. [Method] Nutrient solution containing low concentrations of Mn2+, Cu2+ or Zn2+ were used for cultivating the grafted cucumber seedlings for the cold treatment. [Result] The results indicated that reducing the concentrations of Mn2+, Cu2+ or Zn2+ in nutrient solution had declined the SOD activities in grafted cucumber leaves and increased the rates of electrolytic leakage. Mn2+ had shown the maximum influences, followed by Cu2+, and Zn2+ had shown the minimum influences. [Conclusion] Cold resistance of cucumber can be improved by changing the contents of Mn2+, Cu2+ or Zn2+ in nutrient solution. 展开更多
关键词 Grafted cucumber Microelement Cold stress SOD Rate of electrolytic leakage
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Effects of Different Nitrogen Fertilizer Levels on Fe,Mn,Cu and Zn Concentrations in Shoot and Grain Quality in Rice (Oryza sativa) 被引量:33
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作者 HAO Hu-lin WEI You-zhang YANG Xiao-e FENG Ying WU Chun-yong 《Rice science》 SCIE 2007年第4期289-294,共6页
In a pot experiment, effects of N fertilizer application on the concentrations of Fe, Mn, Cu and Zn in shoot of rice and the quality of brown rice were studied. In the treatments with N fertilizer application, the con... In a pot experiment, effects of N fertilizer application on the concentrations of Fe, Mn, Cu and Zn in shoot of rice and the quality of brown rice were studied. In the treatments with N fertilizer application, the concentrations of Fe, Mn, Cu and Zn in most parts of rice shoot increased compared with control (no N fertilizer application). This indicated that the transportation ability of microelements from root to shoot in rice was improved with N fertilizer application. Effect of N fertilizer on IR68144 was similar to that of on IR64, but the concentrations of the microelements in plant differed, suggesting that the characteristic expression of the two rice genotypes was not controlled by the amount of N fertilizer supplied. The concentrations of those microelements in brown rice increased at first and then decreased with increasing N fertilizer application, reaching the highest at 160 kg/ha, at which the Fe, Mn, Cu and Zn concentrations in brown rice increased by 28.96%, 41.34%, 58.31% and 16.0% for IR64, and by 22.16%, 13.75%, 8.75% and 20.21% for IR68144 compared with control, respectively. Moreover, N fertilizer promoted the accumulation of protein, decreased the accumulation of amylose in grain, and enhanced gel consistency of brown rice. These results indicate that appropriate N fertilizer management could increase micronutrient contents in grain and improve nutrition quality of rice. 展开更多
关键词 RICE nitrogen fertilizer microelement quality trait nutrient concentration protein content amylose content
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Effects of Different Lead Compounds on Growth and Heavy Metal Uptake of Wetland Rice 被引量:13
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作者 CHENHUAI-MAN ZHENGCHUN-RONG 《Pedosphere》 SCIE CAS CSCD 1991年第3期253-264,共12页
Effects of different lead compounds, PbCl2, Pb(NO3)2 and Pb(OAc)2, on the rice growth and uptake of lead and some microelements by wetland rice were studied. The results showed that the seed germination, rice seedling... Effects of different lead compounds, PbCl2, Pb(NO3)2 and Pb(OAc)2, on the rice growth and uptake of lead and some microelements by wetland rice were studied. The results showed that the seed germination, rice seedling growth, chlorophyl content, grain yield and uptake of Pb, Cu, Zn, Fe and Mn by rice plant were affected by the chemical forms of Pb compounds added in soil to a certain degree. The germination rate and the amount of chlorophyl decreased remarkably with increasing Pb concentration, the root extension was restrained obviously by the presence of Pb, and the effect of PbCl2 was more evident than that of Pb(NO3)2 or Pb(OAc)2. The pot incubation test with yellow brown soil and red soil showed that there was no significant regularity in effect of Pb on grain yield, but the difference in the influence of various Pb compounds on yield was clearer. The effect on the amount of Pb in straw and brown rice was in the sequence of Pb(NO3)2> Pb(OAc)2> PbCl2. In case the content of Pb in brown rice was 0.5 mg/ kg, the relative loading capacities of yellow brown soil for Pb added as PbCl2, Pb(OAc)2 and Pb(NO3)2 were 100, 90 and 60 respectively. Pb uptake by wetland rice was closely related to the chemical species of Pb in soil, but there was no comparability among chemical forms of different Pb compounds in the same soil. The uptake of Cu, Zn, Fe and Mn by wetland rice was markedly affected by the addition of Pb, and different Pb compounds varied in their impacts on the uptake of other metals by different organs of wetland rice, e.g. the concentration of Fe in root increased significantly (r = 0.92), while opposite was true for Fe in brown rice (r =-0.92) due to the application of Pb(OAc), in soil. These results demonstrate that the effect of accompanying anions of Pb on the physiological and biochemical processes of wetland rice was rather complex. 展开更多
关键词 ANION loading capacity of soil microelement PB RICE
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Decomposition patterns of leaf litter of seven common canopy species in a subtropical forest: dynamics of mineral nutrients 被引量:12
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作者 XU Xiao-niu Hideaki SHIBATA Tsutomu ENOKI 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第1期1-6,共6页
Dynamical patterns of mineral elements during decomposition processes were investigated for seven common canopy species in a subtropical evergreen broad-leaved forest by means of litterbag technique over 2 years. The ... Dynamical patterns of mineral elements during decomposition processes were investigated for seven common canopy species in a subtropical evergreen broad-leaved forest by means of litterbag technique over 2 years. The species studied are representative for the vegetation in the study area and differed significantly in chemical qualities of their litter. No significant relationships were found between decomposition rate (percentage dry mass remaining and decomposition constant k) and initial element cuncentrations.However, there were significant correlations betweeu the percentage of dry mass remaining and the mineral element concentrations in the remaining litter for most cases. The rank of the element mobility in decomposition process was as follows: Na = K 〉 Mg ≥ Ca 〉 N ≥ Mn ≥ Zn ≥ P 〉 Cu 〉〉 Al 〉〉 Fe. Concentrations of K and Na decreased in all species as decomposition proceeded. Calcium and Mg also decreased in concentrntion but with a temporal increase in the initial phase of decomposition, while the concentrations of other elements (Zn, Cu, AL and Fei increased for all species with exception of Mn which revealed a different pattern in different species. In most species, microelements (Cu, Al, and Fe) significantly increased in absolute amounts at the end of the litterbag incubation, which could be ascribed to a lange extent to the mechanism of abiotic fixation to humic substances rather than biological immobilization. 展开更多
关键词 Canopy species Element release Litter decomposition Litterbag experiment Microelement Evergreen broad-leaved forest
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Distribution of Microelements and Their Influence on the Corrosion Behavior of Aluminum Foil 被引量:7
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作者 Weimin MAO, Heng JIANG, Ping YANG, Huiping FENG and Yongning YUDepartment of Materials, University of Science and Technology Beijing, Beijing 100083, ChinaProf., Ph.D., 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第1期43-46,共4页
The distribution of microelement Fe, Si, Cu and Mg in the surface layer of aluminum foil annealed at 300℃ and 500℃ were determined by secondary ion mass spectrometer. The corrosion structure produced by electrochemi... The distribution of microelement Fe, Si, Cu and Mg in the surface layer of aluminum foil annealed at 300℃ and 500℃ were determined by secondary ion mass spectrometer. The corrosion structure produced by electrochemical etching was also observed. It was found that the Mg concentration at external surface was increased exponentially over the fourth degree and promoted by higher annealing temperature, which will increase the number of corrosion pits inside the large grains, and therefore the specific capacity of the foils for electrolytic capacitors. The similar effects of microelement Fe, Si and Cu were not so strong. 展开更多
关键词 Electrolytic capacitor Aluminum foil Microelement Corrosion structure
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Photosynthetic capability and Fe, Mn, Cu, and Zn contents in two Moraceae species under different phosphorus levels 被引量:2
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作者 Deke Xing Yanyou Wu +3 位作者 Rui Yu Yansheng Wu Chuan Zhang Zheng Liang 《Acta Geochimica》 EI CAS CSCD 2016年第3期309-315,共7页
The strong adaptability of Broussonetia papyrifera (L.) Vent. to low phosphorus (P) conditions can be attributed to the large amount of root-exuded organic acids and the high efficiency of P extraction. However, m... The strong adaptability of Broussonetia papyrifera (L.) Vent. to low phosphorus (P) conditions can be attributed to the large amount of root-exuded organic acids and the high efficiency of P extraction. However, microelement contents are influenced by low-P stress, and their effects on the photosynthetic capability of B. pa- pyrifera remain unknown. In this study, we investigated the effects of low-P treatment on net photosynthetic rate (PN); chlorophyll a fluorescence (ChlF) characteristics; and Fe, Mn, Cu, and Zn contents of B. papyrifera and Morus alba L. seedlings. Results show that B. papyrifera exhibited better photosynthetic capability under moderate P defi- ciency (0.125, 0.063, and 0.031 mmol/L P treatments), whereas the photosynthetic capability of M. alba decreased under moderate and severe P deficiency (0.016 and 0 mmol/L P treatments). Under moderate P deficiency, the decrease in Cu and Zn contents in B. papyrifera was lower than that in M. alba. Under severe P deficiency, a consid- erable decrease of photosynthetic capability in B. pa- pyrifera and M. alba was associated with low Cu and Zn contents. The PN of the two Moraceae species exhibited a better correlation with Cu and Zn contents than with Fe or Mn content. P deficiency could not only decrease cyclic photophorylation and photosynthetic efficiency, but could also affect the stability of thylakoid membrane structureand electron transport efficiency by influencing the con- tents of Cu or Zn, thereby affecting photosynthesis. 展开更多
关键词 ADAPTABILITY Chlorophyll a fluorescence Microelement Organic acids SENSITIVE
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Preliminary Study on Spatial Variability and Distribution of Soil Available Microelements in Pinggu County, Beijing, China 被引量:3
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作者 WANG Shu-ying YU Tong-quan WANG Jian-li YANG Liu YANG Kai LU Ping 《Agricultural Sciences in China》 CAS CSCD 2008年第10期1235-1244,共10页
The objectives of this study were to explore the spatial distribution of soil available microelements and to provide a firm foundation for scientifically formulated fertilizer. 1 076 soil samples were collected from P... The objectives of this study were to explore the spatial distribution of soil available microelements and to provide a firm foundation for scientifically formulated fertilizer. 1 076 soil samples were collected from Pinggu County of Beijing, China, and the contents of available Cu, Zn, Fe, and Mn in topsoil (0-20 cm) and subsoil (20-40 cm) were analyzed respectively. Descriptive statistics and geostatistics were used to analyze the data. The mean values of topsoil available Cu, Zn, Fe, and Mn were 1.96, 2.51, 17.32, and 10.91 mg kg^-1, respectively, which were at medium or at slightly above medium level. The topsoil content of the soil available microelements was more than that of subsoil. The result of semivariance analysis showed that the topsoil available Fe and Mn were spatially correlated at a larger distance of 21.6 and 45.3 km, and the available Cu and Zn were at a shorter distance of 3.1 and 2.9 km, respectively. The subsoil spatial correlation distances were obviously different from the topsoil, which were in the order of available Mn 〉 Cu 〉 Zn = Fe. The Kriging method was applied to calculate the unobserved points and was used to generate the contour map. The results showed that the structural factors, such as topology, soil types, and soil properties, were the main factors influencing the spatial distribution of topsoil available Fe and Mn. Topsoil available Cu and Zn contents were mainly affected by land use, and their contents in orchard and in vegetable land were greatly higher than in field. The spatial distribution of subsoil microelements was similar to that of the topsoil, which exhibited vertical distribution patterns. Fertilizer and pesticide application resulted in the higher contents of available Cu and Zn in Pinggu County. The higher content of available Zn is potentially harmful to soil environmental quality, which should be inspected. 展开更多
关键词 soil available microelements SEMIVARIANCE spatial variability
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MIGRATION CHARACTERISTICS OF MICROELEMENTS IN PROCESS OF LANDSCAPE GEOCHEMISTRY IN MT.NAMJAGBARWA AREA 被引量:1
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作者 窦贻俭 彭补拙 +2 位作者 赵培道 刘育民 李春华 《Chinese Geographical Science》 SCIE CSCD 1992年第3期51-61,共11页
To provide scientific basis for appraising natural resources in Mt. Namjagbarwa area, the migration characteristics of geochemical microelements, such as Zn, V, Ti, Pb, Ni, Cu, Cr, Co, Be and Ba, in the landscape zone... To provide scientific basis for appraising natural resources in Mt. Namjagbarwa area, the migration characteristics of geochemical microelements, such as Zn, V, Ti, Pb, Ni, Cu, Cr, Co, Be and Ba, in the landscape zones of alpine scrub and meadow, the mountainous dark coniferous forest, the mountainous mixed broadleaf and coniferous forest, the mountainous quasi-subtropical semi-evergreen broadleaf forest, the mountainous subtropical evergreen broadleaf forest, and the valley quasi-tropical monsoon rainforest have been described in the paper. 展开更多
关键词 microelement MIGRATION LANDSCAPE ZONE Mt. Namjagbarwa area
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Effect of Combined Application of Boron and Molybdenum Microelement Fertilizer on Cowpea Yield and Quality 被引量:3
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作者 Lizhen CHEN Jianqiu YE +1 位作者 Rongxiang WANG Xiaoqing ZHAO 《Asian Agricultural Research》 2016年第10期90-92,104,共4页
Through field plot experiment,we research the influencing factors of cowpea yield and quality after applying boron and molybdenum microelement fertilizer. Results show that the application of boron and molybdenum micr... Through field plot experiment,we research the influencing factors of cowpea yield and quality after applying boron and molybdenum microelement fertilizer. Results show that the application of boron and molybdenum microelement fertilizer can significantly increase the yield and improve the quality of cowpea. Compared with the control,yield per mu increases by 5. 08- 18. 86%; N content increases by 4. 27%-11. 28%; P content increases by 2. 13%- 13. 57%; K content increases by 2. 00%- 18. 48%; crude protein increases by 4. 16%-19. 94%; vitamin C increases by 2. 71%- 11. 79%; nitrate content decreases by 5%- 15%. Besides,it is better to combine boron with molybdenum than to use each of them separately. 展开更多
关键词 Boron and molybdenum microelement fertilizer COWPEA Yield and quality
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Clinical Effect of Fuzheng Jiedu Granule (扶正解毒颗粒) on Serum NO, NOS and Microelements in Patients with Coronary Heart Disease in Long-term Contact with Nickel 被引量:1
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作者 赵健雄 魏自太 +6 位作者 朱玉真 王学习 尹春 李卉 党宗彦 孟丽红 杨正芳 《Chinese Journal of Integrated Traditional and Western Medicine》 2004年第4期254-258,共5页
Objective: To study the clinical effect of Fuzheng Jiedu granule (扶正解毒颗粒,FJG) and its influence on serum nitric oxide (NO), nitric oxide synthase (NOS) and microelements in patients with coronary heart disease w... Objective: To study the clinical effect of Fuzheng Jiedu granule (扶正解毒颗粒,FJG) and its influence on serum nitric oxide (NO), nitric oxide synthase (NOS) and microelements in patients with coronary heart disease who are in long-term contact with nickel. Methods: Sixty patients were randomly divided into two groups, the treated group and the control group, 30 in each group. Conventional Western medicinal treatment was applied to both groups, but to the treated group, FJG was given additionally by oral intake, and the therapeutic course for both groups was 4 weeks. Besides, a health control group was set up with 15 healthy subjects selected from the same area, who had no history of contact with nickel. Clinical symptoms of the patients and changes in their electrocardiogram (ECG) and serum levels of NO, NOS and microelements were observed before and after treatment. Results: The total effective rate on clinical symptoms in the treated group was 93. 3% and that in the control group 63. 3% , comparison between the two showing significant difference (P<0.05); the total effective rate on ECG in the two groups was 90.0% and 56.7% respectively, which also showed significant difference (P<0.05). After treatment, levels of serum NO, NOS, Mg, Zn and Ca increased and those of Ni, Mn and Fe decreased significantly (P<0.05 or P<0.01) in the treated group, while in the control group, changes in these laboratory indexes were insignificant. Conclusion: FJG could lower the blood nickel level and regulate the unbalance of microelements, help restore serum NO and NOS in persons exposed to nickel and improve the clinical symptoms of patients with coronary heart disease and in long-term contact with nickel. 展开更多
关键词 NICKEL Fuzheng Jiedu granule nitric oxide synthase nitric oxide microelement
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Microwave digestion polarography for determining seven trace elements in Salvia Miltiorrhiza Root and compound Salvia Miltiorrhiza Root injection simultaneously 被引量:1
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作者 黄熠 张泰铭 +1 位作者 曹娟 梁逸曾 《Journal of Central South University of Technology》 EI 2007年第4期514-519,共6页
The sensitive second derivative waves of Cu(Ⅱ),Pb(Ⅱ),Cd(Ⅱ),Ni(Ⅱ),Zn(Ⅱ),Fe(Ⅱ)and Mn(Ⅱ),forming in the substrate solution(pH=9.26)consisting of ammonia,ammonium chlorid,gelatin and ascorbic acid were researched.T... The sensitive second derivative waves of Cu(Ⅱ),Pb(Ⅱ),Cd(Ⅱ),Ni(Ⅱ),Zn(Ⅱ),Fe(Ⅱ)and Mn(Ⅱ),forming in the substrate solution(pH=9.26)consisting of ammonia,ammonium chlorid,gelatin and ascorbic acid were researched.The peak potentials of the polarographic waves of the seven ions are at about 0.48,0.63,0.79,1.04,1.28,1.44 and 1.60 V respectively.Combining with microwave technique,a new method for the simultaneous determination of the seven trace elements in Chinese traditional medicine was developed.The method is easy to operate,rapid,simple and convenient.When the signal-to-noise rate equals 3,the detection limits of Cu,Pb,Cd,Ni,Zn,Fe and Mn are 4.2×10 3,5.3×10 3,2.1×10 3,5.8×10 4,3.0×10 3,7.7×10 4 and 1.1×10 3 μg/mL respectively.Well linear relationships exist between the concentrations and the peak currents when Cu,Pb,Cd,Ni,Zn,Fe and Mn concentrations are within 8.5×10 3 10,9.7×10 3 10,4.5×10 3 10,1.2×10 3 10,6.4×10 3 10,1.5×10 3 10 and 2.8×10 3 10 μg/mL,respectively.The method has been used to the simultaneous determination of the seven trace elements in Salvia Miltiorrhiza Root and compound Salvia Miltiorrhiza Root injection,the relative standard deviations(RSDs)of the Cu,Pb,Cd,Ni,Zn,Fe and Mn in the two medicines are 3.9% and 5.8%,4.0% and 4.1%,4.3% and 5.7%,4.9% and 5.3%,4.4% and 4.7%,3.5% and 4.0%,0.51% and 2.8%,respectively;the comparisons of the determination results with the values obtained by the standard method indicate that the presented method has very well veracity. 展开更多
关键词 derivative polarographic wave microelement Salvia Miltiorrhiza Root compound Salvia Miltiorrhiza Root injection
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新疆哈萨克族食管癌患者全血及头发中微量元素的分析 被引量:1
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作者 安长新 杨卫星 +7 位作者 赵峰 栗继茹 戴宏 魏新昌 张怀祥 陈淑英 王智娟 朱凤贤 《微量元素与健康研究》 CAS 1993年第4期20-21,共2页
微量元素与肿瘤的发生、发展及治疗有密切的关系。新疆哈萨克族食管癌患病率较高,为了探讨食管癌与微量元素的关系,我们于1990年8月至1992年7月对新疆部分哈萨克族食管癌高发区患者全血及头发中部分无机元素含量进行了测定。材料与方法1... 微量元素与肿瘤的发生、发展及治疗有密切的关系。新疆哈萨克族食管癌患病率较高,为了探讨食管癌与微量元素的关系,我们于1990年8月至1992年7月对新疆部分哈萨克族食管癌高发区患者全血及头发中部分无机元素含量进行了测定。材料与方法1.样品采集:选用新疆新源县及阿勒泰地区食管癌高发区。 展开更多
关键词 Kazak NATIONALITY ESOPHAGEAL cancer WHOLE blood HAIR Microelement
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Microelements Distribution in Sulfides from Black Smokers of Hydrothermal Vent Field Broken Spur(MAR)
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作者 A.Yu.Lein P.P.Shirshov A.A.Ulyanov 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期179-179,共1页
Numerous investigations on submarine hydrothermal ore-forming occurrence have been actively carried out in the last two decades with significant results.The Ag and Au enrichments in the sulfides from black smokers ofh... Numerous investigations on submarine hydrothermal ore-forming occurrence have been actively carried out in the last two decades with significant results.The Ag and Au enrichments in the sulfides from black smokers ofhydrothermal vent field Broken Spur(MAR) aroused our interest to study their mineral hosting forms.Samples were collected from seven hydrothermal chimneys within Broken Spur in the British-Russian BRAVEX(1994) and 展开更多
关键词 broken SPUR black SMOKER SUBMARINE sulfide MICROELEMENTS DISTRIBUTION
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Ecological and geochemical aspects of interlayer water use for potable water supply of urban population:a case study in the Dnieper–Donetsk aquifer system,Ukraine
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作者 Tetiana Koshliakova Kateryna Zlobina Iryna Kuraieva 《Acta Geochimica》 EI CAS CSCD 2023年第3期535-551,共17页
The article is devoted to the study of ecological and geochemical features of interlayer waters of the Dnieper–Donetsk aquifer system in Ukraine,used for the potable water supply of Kyiv.A wide range of methods was u... The article is devoted to the study of ecological and geochemical features of interlayer waters of the Dnieper–Donetsk aquifer system in Ukraine,used for the potable water supply of Kyiv.A wide range of methods was used,including Microsoft Excel,Statistica,and Attestat software packages,MapInfo Professional 6.5 and ArcGIS-ArcMap 9.3 programs;the method of mass spectrometry with inductively coupled plasma(ICP-MS)and GEMS software were performed.Monitoring study results(during 2007–2023)were analyzed for two interlayer aquifers—Cenomanian-Callovian groundwater complex and Bajocian aquifer.It was determined that the normalized value of mineralization increased with a decrease in water intake during 1980–2010,which indicates a relative increase in the content of mineral substances during longterm exploitation.A high negative correlation(Kcor.=-0.54 to-0.86)is also typical for normalized values of oxidizability,total hardness,pH,Ca,Mg,and Cl content.Comparative analysis of two different aquifers revealed that the macrocomponent composition of Bajocian aquifer remains stable,once for Cenomanian-Callovian groundwater complex,there is a tendency to decrease hydrogen carbonates and increase chlorides and sulfates,whereas the cation composition remains relatively stable.A significant increase(by 55%)of the total mineralization in the representative well located on the right bank of the Dnieper River was found.There is also a significant increase(by more than 5 times)in the iron content,which the authors associate with the unsatisfactory technical condition of the well casing pipes.Physico-chemical modeling of trace elements,performed for investigated aquifers,shows that both aquifers are characterized by the predominant migration of the following metals in the cationic form(aqua-ions):Ca,Mg,Na,Ba,Co,Cu,Mn,Ni,Sr,Zn.It was found that the predominant migration forms of metals in the studied interlayer waters are free uncomplexed ions,carbonate,and hydroxo complexes. 展开更多
关键词 Interlayer water HYDROGEOCHEMISTRY Environmental geochemistry MICROELEMENTS Migration forms Biologically significant concentrations
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THREE-DIMENSIONAL STATIC ANALYSES FOR FGM PLATES WITH MEDIUM COMPONENTS AND DIFFERENT NET STRUCTURES
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作者 Hongmei Cheng Zhiyuan Cao 《Acta Mechanica Solida Sinica》 SCIE EI 2010年第2期167-174,共8页
A new microelement method for the analyses of functionally graded structures was proposed. The key of this method is the maneuverable combination of two kinds of elements. Firstly, the macro elements are divided from ... A new microelement method for the analyses of functionally graded structures was proposed. The key of this method is the maneuverable combination of two kinds of elements. Firstly, the macro elements are divided from the functionally graded material structures by the normal finite elements. In order to reflect the functionally graded distributions of materials and the microconstitutions in each macro-element, the microelement method sets up the dense microelements in every macro-element, and translates nodes to the same as the normal finite elements by the degrees of freedom of all microelemental the compatibility conditions. This microelement method can fully reflect the micro constitutions and different components of materials, and its computational elements are the same as the normal finite elements, so it is an effective numerical method for the analyses of the functionally graded material structures. The three-dimensional analyses of functionally graded plates with medium components and different micro net structures are given by using the microelement method in this paper. The differences of the stress contour in the plane of functionally graded plates with different net microstructures are especially given in this paper. 展开更多
关键词 functionally graded materials medium components different net structures three-dimensional analyses microelement method span-scale analyses
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Investigation on mechanism of reducing diffusible hydrogen in weld using microelements
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作者 DU Zeyu DING Ping and ZHANG Wenyue(Materials Science and Engineering Department,Tianjin University,Tianjin,300072,P.R.China.) 《China Welding》 EI CAS 1996年第2期125-131,共7页
In this paper,the influence of microelements yttrium(Y)and tellurium(Te)on the diffusible hydrogen in weld bead has been investigated in a systemic way by means of alloying addition in the molten pool(AAMP).The result... In this paper,the influence of microelements yttrium(Y)and tellurium(Te)on the diffusible hydrogen in weld bead has been investigated in a systemic way by means of alloying addition in the molten pool(AAMP).The results indicate that AAMP can notably reduce the diffusible hydrogen,economize the precious microelements microelements and improve the technological properties.Thus the microelements will play an important role in further developing the welding materials.This paper lays emphasis on the discussion of the mechanism of reducing hydrogen by microelements Y and Te.It is considered from the results that both Y and Te belong to surface active elements and can reduce the diffusible hydrogen in weld bead because they can change the surface properlies of molten pool metal and reduce the absorption of hydrogen atom in arc space of liquid metal surface.This research has a great significance in the development and utilization of microelements in welding. 展开更多
关键词 MICROELEMENTS diffusible hydrogen surface active elements weld bead
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Combined Action of Copper with IAA on Individual Amino Acids and Microelement in Pods of Two Broad Bean Cultivars
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作者 Hamdia Mahmoud Abd El-Samad Mohamed Abdo Kheder Shaddad Khloud Nagy Shaker 《American Journal of Plant Sciences》 2019年第4期670-697,共28页
It is worthy to mention that the two broad bean cultivars displayed a surprising situation during the fruiting stage of growth. The absolute amount of pods yield was higher in cv. Assiut 125 than in cv. Assiut 84. Thi... It is worthy to mention that the two broad bean cultivars displayed a surprising situation during the fruiting stage of growth. The absolute amount of pods yield was higher in cv. Assiut 125 than in cv. Assiut 84. This situation was in contrast with that in the vegetative stage, where cv. Assiut 84 produced greater vegetative growth than cv. Assiut 125. Although the cv. Assiut 84 was less affected by the highest dose of copper, the cv. Assiut 125 was greatly affected by this dose. However, another surprising situation was recorded when the absolute values of fresh and dry matter of cv. Assiut 125 were much higher than cv. Assiut 84 at any used copper concentration. The fresh matters of the pods of cv. Assiut 84 and cv. Assiut 125 were 7.24 and 10.16 gm at the level of control and 6.69 and 7.59 gm at the level of 350 ppm Cu, respectively. Their dry matters were 1.99 and 3.52 gm at the level of control and 1.77 and 2.13 gm at the level of 350 ppm Cu2+ in cv. Assiut 84 and cv. Assiut 125, respectively. This contradiction was also extended when these copper-affected cultivars were sprayed by IAA. The cv. Assiut 84 responded slightly to IAA treatment. On the other hand, a considerable increase in the dry matter yield was recorded in the pods of cv. Assiut 125 at any used level of copper when compared to the non-sprayed plants treated by the same copper concentration. At the level of 350 ppm Cu2+ , the pod yield was 2-fold that of plants treated only by 350 ppm Cu2+ , without IAA spraying. Thus, even IAA behaved differently in its effect on the crop yield of the two tested broad bean cultivars. There are big and surprising variations in the accumulation of microelements and heavy metals in pods among the two broad bean genotypes, whatever the treatments used. These variations seemed to be complicated which might need further studies. The concentration of amino acids and their individuals also varied among the two cultivars;they increased in cv. Assiut 84 and decreased in cv. Assiut 125. The increased amino acids in cv. Assiut 84 are mostly used as precursors for phytochelatins. For the previous studies, thus the present work was conducted to explain the effect of Cu and interactive effect with IAA on two selected broad bean cultivars Assiut 84 and Assiut 125 during yielding production. 展开更多
关键词 Synergistic Effect Amino ACIDS Microelement BROAD BEAN CULTIVARS
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Prospects and Problems of Implementation of Recreation Works in Degradated Areas
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作者 Abdukholikov Farrukh Bakhrom O’g’li Karshibaev Hazratkul Kilichevich Masudjon Norkulov Marufovich 《American Journal of Plant Sciences》 CAS 2023年第4期506-516,共11页
This article is devoted to work aimed at normalizing the condition of degraded soils in open-pit mines as a result of anthropogenic influences through phytomass. By creating a biological cover from plants, it has been... This article is devoted to work aimed at normalizing the condition of degraded soils in open-pit mines as a result of anthropogenic influences through phytomass. By creating a biological cover from plants, it has been achieved to improve the composition of the soil. Plants such as Datura starmonium, Portuluca oleracea, Caspella bursa-pastoris, Chenopodium vulvaria, Chenopodium album, Plantago lanceolata, Vaccaria hispanica, Vicia angustifolia were used for the research. The effect of micronutrients on plants was studied. 展开更多
关键词 FLORA Introducer PHYTOMASS Degradation Technical Recultivation Biological Recultivation Microelement
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