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人类聚居环境剖析——聚居社区元素演化研究 被引量:10
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作者 刘滨谊 毛巧丽 《新建筑》 1999年第2期14-17,共4页
基于人类聚居环境概念,提出聚居社区的拓扑元素。通过实例调查、元素量化,揭示聚居社区的演变规律及发展规模。
关键词 人类聚居 聚居社区 聚居环境 元素量化 演变规律
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合金元素减量化HG785钢的连续冷却转变规律研究
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作者 陈丽娟 赵隆崎 +2 位作者 蔡珍 刘洋 韩斌 《钢铁研究》 CAS 2014年第6期37-39,共3页
利用THERMECMASTOR-Z热模拟机研究了合金元素减量化的HG785钢在连续冷却下的组织变化规律,绘制了动态CCT曲线。结果表明:随着冷却速度的提高,合金元素减量化HG785钢的组织由多边形铁素体逐渐向贝氏体类转变;冷却速度在30℃/s左右时,得... 利用THERMECMASTOR-Z热模拟机研究了合金元素减量化的HG785钢在连续冷却下的组织变化规律,绘制了动态CCT曲线。结果表明:随着冷却速度的提高,合金元素减量化HG785钢的组织由多边形铁素体逐渐向贝氏体类转变;冷却速度在30℃/s左右时,得到的贝氏体组织晶粒细小均匀,晶界交错,这种组织结构有利于获得高强度和高韧性。 展开更多
关键词 合金元素量化 HG785 CCT曲线 贝氏体
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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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Studies on a Traditional Chinese Medical Prescription Ma Xing Shi Gan Tang by Bio-coordination Chemistry 被引量:2
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作者 陈求浩 吴炳辅 崔万钧 《Journal of Chinese Pharmaceutical Sciences》 CAS 1993年第1期85-87,共3页
本文报道 pH 电位滴定法测出麻黄碱与生石膏中的 Cu^(2+)、Fe^(2+)、Zn^(2+)、Mn^(2+)离子形成的 ML 及 ML_2型络合物的稳定常数。滴定曲线显示甘草酸与上述四种金属离子也能分别形成不同稳定程度的络合物。用麻黄碱加甘草酸和上述四种... 本文报道 pH 电位滴定法测出麻黄碱与生石膏中的 Cu^(2+)、Fe^(2+)、Zn^(2+)、Mn^(2+)离子形成的 ML 及 ML_2型络合物的稳定常数。滴定曲线显示甘草酸与上述四种金属离子也能分别形成不同稳定程度的络合物。用麻黄碱加甘草酸和上述四种金属离子配制成的模拟麻杏石甘汤和单纯生石膏煎剂与麻性石甘汤一样均有使家兔退热的效果,与对照组比较均有显著性差异(P<0.05);而用麻黄碱加甘草酸配制成的溶液无退热效果。作者认为应从生物—配位无机化学的多金属—多配体体系的观点去研究某些传统中医药方剂。 展开更多
关键词 Traditional Chinese Medical Prescription Trace Elements Bio-coordination Chemistry Decoction of Chinese Ephedra Apricot Kernel Gypsum and Licorice
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Research on Stoichiometry of Early-spring Herbs Functional Group in the Subtropical Artificial Wetland
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作者 牛晓音 常杰 +1 位作者 葛滢 郑家文 《Agricultural Science & Technology》 CAS 2011年第8期1182-1185,1190,共5页
[Objective]The aim was to carry out stoichiometry on the early-spring herbs functional group in subtropical artificial wetland.[Method]UV-Vis spectrophotometer was used for the determination of nitrate-nitrogen,ammoni... [Objective]The aim was to carry out stoichiometry on the early-spring herbs functional group in subtropical artificial wetland.[Method]UV-Vis spectrophotometer was used for the determination of nitrate-nitrogen,ammonium nitrogen and phosphorus concentrations.Potassium persulfate absorptiometry was used for the measurement of total N content,while the flame photometer was used to detect the potassium and sodium concentration in plants.All the nutrient determination of plant samples were repeated for four times.[Result]The four nutrient concentrations in almost all samples were in the normal range of natural plant nutrition concentrations;in early-spring herbs functional groups,different species showed diversity on the nutrient concentrations;plant height had no significant effect on the nutrient concentrations in plants;the nutrient concentrations of non-grass group plants were higher than that of grass group plants;the nutrient concentrations of the annual herb were higher than that of perennial herbs.[Conclusion]The study had provided basis for the understanding of the effects of changes in nutritional conditions on species diversity,community structure and succession of the system. 展开更多
关键词 Early-spring herbs Functional group BIODIVERSITY Element STOICHIOMETRY
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高职英语学习者定式小句入场方式的实证研究
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作者 张靖宇 《扬州教育学院学报》 2019年第2期40-44,94,共6页
入场反映了认知主体参照言语事件的语境“安置”某一实体的过程。在对定式小句所表达的概念实施入场操作过程中,高职英语学习者呈现出显著的特点。他们在使用英语表征概念时具有语境定位意识,能遵循突显概念优先原则聚焦现实世界空间。... 入场反映了认知主体参照言语事件的语境“安置”某一实体的过程。在对定式小句所表达的概念实施入场操作过程中,高职英语学习者呈现出显著的特点。他们在使用英语表征概念时具有语境定位意识,能遵循突显概念优先原则聚焦现实世界空间。高职学生偏向使用有定入场策略,采用近距式入场元素标记意指对象。由于学生无法有效了解远、近距式元素对动作完成性的语义限制,所以他们在使用高语义限制的近距式元素时呈现较高的错误率。此外,高职学生存在量化入场元素过量使用的现象。由于他们一方面对量化入场元素的时间语义认识模糊,另一方面对情态动词的参照点缺乏区分意识,导致低水平英语学习者在使用量化入场元素时出现错误。 展开更多
关键词 入场 定式小句 有定入场元素 量化入场元素
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Differences of Physiological and Biochemical Indexes of Upper Fresh Leaves and Post-growth Roots in Different Quality Stages 被引量:1
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作者 谢碧君 裴晓东 +5 位作者 邓小华 蔡兴 何命军 李帆 黄松青 陈金 《Agricultural Science & Technology》 CAS 2017年第11期2033-2036,2044,共5页
In order to explore the physiological and biochemical characteristics of fresh upper leaves and roots of different qualities of tobacco, the malonaldehyde (MDA), superoxide dismutase (SOD) activity, chlorophyllase... In order to explore the physiological and biochemical characteristics of fresh upper leaves and roots of different qualities of tobacco, the malonaldehyde (MDA), superoxide dismutase (SOD) activity, chlorophyllase activity, amylase activity, medium trace element content, chemical component content, root fresh weight, dry weight and activity in the normal tobacco leaves, tobacco leaves rich in nutrients and premature grey tobacco leaves were studied. The results showed that compared with the normal tobacco leaves, the root fresh weight, dry weight and activity in the premature grey tobacco leaves decreased by 41.22%, 14.44% and 60.29% respectively, while malonaldehyde content increased by 34.82%, and chlorophyllase, α-amylase, β-amylase and SOD activity declined by 89.55%, 65.71%, 71.26% and 37.25% respectively. Chlorophyllase, co-amylase and 13-amylase activity in the tobacco leaves rich in nutrients decreased by 58.76%, 36.19% and 41.93% respectively. The content of medium trace elements in the tobacco leaves rich in nutrients and premature grey tobacco leaves was lower than that of the normal tobacco leaves. Starch, total sugar, reducing sugar and potassium content in the normal tobacco leaves were higher than that of the tobacco leaves rich in nutrients and premature grey tobacco leaves. 展开更多
关键词 Upper tobacco leaves Root activity Physiological and biochemical properties Medium trace elements Chemical components
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Annual and Monthly Variations in Litter Macronutrients of Three Subalpine Forests in Western China 被引量:48
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作者 YANG Wan-Qin WANG Kai-Yun +1 位作者 S. KELLOMAKI ZHANG Jian 《Pedosphere》 SCIE CAS CSCD 2006年第6期788-798,共11页
Macronutrients (N, P, K, Ca, Mg, and S) in litter of three primarily spruce (Picea purpurea Masters) (SF), fir (Abies faxoniana Rehder & E. H. Wilson) (FF), and birch (Betula platyphylla Sukaczev) (BF) ... Macronutrients (N, P, K, Ca, Mg, and S) in litter of three primarily spruce (Picea purpurea Masters) (SF), fir (Abies faxoniana Rehder & E. H. Wilson) (FF), and birch (Betula platyphylla Sukaczev) (BF) subalpine forests in western China were measured to understand the monthly variations in litter nutrient concentrations and annual and monthly nutrient returns via litteffall. Nutrient concentration in litter showed the rank order of Ca 〉 N 〉 Mg 〉 K 〉 S 〉 P. Monthly variations in nutrient concentrations were greater in leaf litter (LL) than other litter components. The highest and lowest concentrations of N, P, K, and S in LL were found in the growing season and the nongrowing season, respectively, but Ca and Mg were the opposite. Nutrient returns via litterfall showed a marked monthly pattern with a major peak in October and one or two small peaks in February and/or May, varying with the element and stand type, but no marked monthly variations in nutrient returns via woody litter, reproductive litter, except in May for the BF, and moss litter. Not only litter production but also nutrient concentration controlled the annual nutrient return and the monthly nutrient return pattern. The monthly patterns of the nutrient concentration and return were of ecological importance for nutrient cycling and plant growth in the subalpine forest ecosystems. 展开更多
关键词 LITTERFALL macronutrient return monthly variation nutrient concentration subalpine forest
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Blood micronutrient, oxidative stress, and viral load in patients with chronic hepatitis C 被引量:6
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作者 Wang-Sheng Ko Chih-Hung Guo +5 位作者 Maw-Sheng Yeh Li-Yun Lin Guoo-Shyng W. Hsu Pei-Chung Chen Mei-Ching Luo Chia-Yeh Lin 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第30期4697-4702,共6页
AIM: To assess the extent of micronutrient and oxidative stress in blood and to examine their linkages with viral loads in chronic hepatitis C patients.METHODS: Hepatitis C virus (HCV)-RNA levels were quantified in th... AIM: To assess the extent of micronutrient and oxidative stress in blood and to examine their linkages with viral loads in chronic hepatitis C patients.METHODS: Hepatitis C virus (HCV)-RNA levels were quantified in the serum from 37 previously untreated patients with chronic hepatitis C. The plasma and erythrocyte micronutrients (zinc, selenium, copper, and iron) were estimated, and malondialdehyde (MDA)contents were determined as a marker to detect oxidative stress. Antioxidant enzymes, superoxide dismutase (SOD),glutathione peroxidase (GPX) and glutathione reductase (GR) activities in blood were also measured. The control group contained 31 healthy volunteers.RESULTS: The contents of zinc (Zn), and selenium (Se)in plasma and erythrocytes were significantly lower in hepatitis C patients than in the controls. On the contrary,copper (Cu) levels were significantly higher. Furthermore,plasma and erythrocyte MDA levels, and the SOD and GR activities in erythrocytes significantly increased in hepatitis C patients compared to the controls. However, the plasma GPX activity in patients was markedly lower. Plasma Se (r= -0.730, P<0.05), Cu (r = 0.635), and GPX (r = -0.675)demonstrated correlations with HCV-RNA loads. Significant correlation coefficients were also observed between HCV-RNA levels and erythrocyte Zn (r = -0.403), Se (r = -0.544), Cu (r = 0.701) and MDA (r = 0.629) and GR (r = 0.441).CONCLUSION: The levels of Zn, Se, Cu, and oxidative stress (MDA), as well as related anti-oxidative enzymes (GR and GPX) in blood have important impact on the viral factors in chronic hepatitis C. The distribution of these parameters might be significant biomarkers for HCV. 展开更多
关键词 MICRONUTRIENT Oxidative stress Viral load Plasma and erythrocytes Hepatitis C
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Correlation Between Chemical Element Contents in Tree Rings and Soils 被引量:8
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作者 QIANJUN-LONG KESHAN-ZHE 《Pedosphere》 SCIE CAS CSCD 1993年第4期309-319,共11页
The annual growth rings of ten trees and the soils near the tree roots were sampled from the mining area of lead-and zinc-dominant metals in the Xixia Mountain, Nanjing, for the determination of chemical element conte... The annual growth rings of ten trees and the soils near the tree roots were sampled from the mining area of lead-and zinc-dominant metals in the Xixia Mountain, Nanjing, for the determination of chemical element contents. The study results showed that the elemental contents in the tree rings were correlated with those in the soils, i. e., the elemental contents in the tree rings increased with those in the soils, even in the cases of different environments and different tree species. Therefore, a time-concentration sequence could be set up on the basis of determining the elemental contents in the successive annual growth rings of trees to qualitatively reflect the annual variations of relevant elements in the soils, and a time-concentration sequence of elemental contents in soils could also be established in terms of related model to reproduce the dynamic changes of the surroundings. 展开更多
关键词 CORRELATION elemental contents SOILS tree rings
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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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Effects of trace element and purification on properties of AZ80 magnesium allo 被引量:2
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作者 李应举 罗天骄 杨院生 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第B07期407-410,共4页
The effects of trace element Fe on the corrosion behavior of AZ80 magnesium alloy were investigated by salt spray test and electrochemical measurements.The results show that the corrosion rate decreases with decreasin... The effects of trace element Fe on the corrosion behavior of AZ80 magnesium alloy were investigated by salt spray test and electrochemical measurements.The results show that the corrosion rate decreases with decreasing the trace element Fe content in an approximately linear relation even though the amount of trace element Fe reduces to 0.000 2%(mass fraction).The electrochemical measurements show that the corrosion potential(φcorr)of the alloy with lower trace element Fe content shifts to less negative value.It is suggested that the control trace element by purification is an effective way to enhance the corrosion resistance of AZ80 magnesium alloy. 展开更多
关键词 magnesium alloy PURIFICATION corrosion rate trace element
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Study on Model of Correlation Between Chemical Ele-ment Contents in Tree Rings and Soils near Tree Roots 被引量:3
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作者 KESHAN-ZHE QIANJUN-LONG 《Pedosphere》 SCIE CAS CSCD 1994年第1期19-26,共8页
The chemical element contents in tree rings are correlated with those in the soils near the tree roots. Theresults in the present study showed that the correlation between them could be described using the followinglo... The chemical element contents in tree rings are correlated with those in the soils near the tree roots. Theresults in the present study showed that the correlation between them could be described using the followinglogarithmic linear correlation model:lgC'(Z) = α(Z) + b(Z)lgC(Z).Therefore, by determining the chrono-sequence C(Z, t), where Z is the atomic number and t the year ofelemental contents in the annual growth rings of trees, we could get the chrono-sequence C'(Z, t) of elementalcontents in the soil, thus inferring the dynamic variations of relevant elemental contents in the soil. 展开更多
关键词 correlation model elemental contents SOILS tree rings
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Research on the relation between the geologic environment and the trace elements of underground water in Huaibei Coalfield 被引量:1
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作者 宋晓梅 胡宝林 +1 位作者 桂和荣 陈陆望 《Journal of Coal Science & Engineering(China)》 2004年第2期42-46,共5页
Based on testing the trace elements of the four main aquifers of underground water in Huaibei Coalfield by using the ICP-MS in the University of Science and Tech- nology of China(USTC), the relation of trace elements ... Based on testing the trace elements of the four main aquifers of underground water in Huaibei Coalfield by using the ICP-MS in the University of Science and Tech- nology of China(USTC), the relation of trace elements of the four main aquifers was analyzed by using maximum correlation coefficient method. The study indicates that the different aquifers posses respective microelement distributional characteristics, which caused with average contents of trace elements in the different aquifers are related to the pH of the underground water and the contents of trace elements of the wall rock source in the research area, so researching on the distribution of geographic space and the change trend of hydro-geochemical character of different aquifers and the relation of the geologic environment and the trace elements conduce to establish the disciminand model of water inrush source. 展开更多
关键词 AQUIFER trace element geochemical characteristic CORRELATIVITY
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Geochemical characteristics of Galandrud coal in central Alborz, Iran 被引量:1
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作者 Ardebili Leila Babazadeh Vasef +1 位作者 Mammadov Mousa Navi Pedram 《International Journal of Mining Science and Technology》 2012年第1期101-106,共6页
This study focuses on the geochemistry of trace elements and parameters of coal quality of bituminous coal belonging to the upper Triassic-lower Jurassic era, collected from the Galandrud region in Central Alborz, nor... This study focuses on the geochemistry of trace elements and parameters of coal quality of bituminous coal belonging to the upper Triassic-lower Jurassic era, collected from the Galandrud region in Central Alborz, northern Iran. Galandrud coal on an air-dried basis are characterized by broad variation in the amount of ash (ranging from 6.49g to 12.73%), a high content of volatile matter (33,32-37.45%) and high gross calorific values (7430-8880 kcal/kg). The mineral matter of the coal samples studied is made up of dolomite (〉909g), quartz, sphalerite, galena, pyrite and clay minerals. Major elements are positively cor- related with ash content suggesting an association with inorganic constituents. Based on statistical anal- yses, concentrations of trace elements such as Co (51.3 ×10^-6-152.9× 10^-6), Ba (368× 10^-6-3297.4×10^-6), Cr (65.5 ×10^-6-194.2 × 10^-6), Mo (5.6 × 10^-6-18.2× 10^-6), Hi (72.9 × 10^-6-152.9 × 10^-6) and V (245.5 × 10^-6-520 ×10^-6) are higher than world coal averages. However, low concentration of some vol- atile elements such as As, Hg and U are present in low concentrations of the various types of coal studied. 展开更多
关键词 Galandrud coals GEOCHEMISTRY Trace elements Central Alborz lran
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Species Transformation of Trace Elements and Their Distribution Prediction in Dyestuff Residue Incineration 被引量:4
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作者 谭中欣 李海滨 +2 位作者 王小亮 蒋旭光 严建华 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第2期268-275,共8页
The release of heavy metals from the combustion of hazardous wastes is an environmental issue of in-creasing concern.The species transformation characteristics of toxic heavy metals and their distribution are consid-e... The release of heavy metals from the combustion of hazardous wastes is an environmental issue of in-creasing concern.The species transformation characteristics of toxic heavy metals and their distribution are consid-ered to be a complex problem of mechanism.The behavior of hazardous dyestuff residue is investigated in a tubular furnace under the general condition of hazardous waste pyrolysis and gasfication.Data interpretation has been aided by parallel theoretical study based on a thermodynamic equilibrium model based on the principle of Gibbs free en-ergy minimization.The results show that Ni,Zn,Mn,and Cr are more enriched in dyestuff residue incineration than other heavy metals(Hg,As,and Se)subjected to volatilization.The thermodynamic model calculation is used for explaining the experiment data at 800℃ and analyzing species transformation of heavy metals.These results of species transformation are used to predict the distribution and emission characteristics of trace elements.Although most trace element predictions are validated by the measurements,cautions are in order due to the complexity of incineration systems. 展开更多
关键词 hazardous waste INCINERATION thermodynamic equilibrium model heavy metals species transformation PREDICTION
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The transformation and concentration of environmental hazardous trace elements during coal combustion 被引量:1
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作者 YAO Duo-xi ZHI Xia-chen 《Journal of Coal Science & Engineering(China)》 2010年第1期74-77,共4页
Studied the content and distribution of 18 environmental hazardous trace elementsin the lignite, fatty coal, anthracite and its burnt products by combustion simulatingexpriment in the one-dismensinal boiler.The transf... Studied the content and distribution of 18 environmental hazardous trace elementsin the lignite, fatty coal, anthracite and its burnt products by combustion simulatingexpriment in the one-dismensinal boiler.The transformations and concentration of 18 traceelements during different coal combustion were discussed.The results show that there aresome content distribution of 18 hazardous trace elements in every burnt product, but thelaw of concentration and dispersion of every trace element during different coal combustionis very different.Experiment results indicate that the transformation and concentrationof trace elements during coal combustion are related to the element contents and occur-rencesof trace elements in raw coal, but are also affected by some man-made factorssuch as the combustion method of boiler, combustion temperature and atmosphere, thetype of precipitators and so on. 展开更多
关键词 environmental hazardous trace elements transformation and concentration coal combustion
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Prediction of Chemical Element Contents in Soils
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作者 KESHAN-ZHE QIANJUN-LONG 《Pedosphere》 SCIE CAS CSCD 1994年第2期105-117,共13页
Assuming that the regularity for the dynamic changes of the chrono-sequences of chemical element contents intree rings follows a k-order constant coefficient differential equation and substituting the differential wit... Assuming that the regularity for the dynamic changes of the chrono-sequences of chemical element contents intree rings follows a k-order constant coefficient differential equation and substituting the differential with the differ-ence, we could obtain the inferred value y_(m+k+1) by the formula: Each coefficient c_i in the formula may be ascertained by use of the measured data in the chrono-sequences. Ex-tending the chrono-sequences on the assumption that the regularity of dynamic changes wouldn't change in the nearfuture, the contents of chemical elements in the soils may be predicted in termis of a logarithmic linear correlationmodel. Also, this extension method could be used for the reproduction of the contents of chemical elements in soilsduring different periods of time in the past. 展开更多
关键词 Chrono-sequences of elemental contents EXTENSION PREDICTION SOILS tree rings
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Vertical variation of trace elements and its relation to the water-bearing capacity of Ordovician strata,in Datun coal field 被引量:1
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作者 LIU Huai-zhong HAN Bao-ping 《Mining Science and Technology》 EI CAS 2009年第2期166-169,共4页
We tested for fourteen trace elements in samples collected from the Ordovician strata in Datun coal field. The vertical concentration variation of these trace dements is reported. The relationship of the variation to ... We tested for fourteen trace elements in samples collected from the Ordovician strata in Datun coal field. The vertical concentration variation of these trace dements is reported. The relationship of the variation to the water-bearing capacity of the Ordovician strata is discussed. The minimum concentration of eleven (of 14 total) trace elements appears in the lower Majiagou formation. The maximum concentrations mainly appear in the Badou and Jiawang formations: eight maxima are located in Badou and four more are in Jiawang. The study of karst development and the water-bearing capacity of Ordovician strata shows that karst is well developed in the Majiagou formation and there is a consequent high water-bearing capacity in this formation: Badou and Jiawang formations are contrary to this situation. The results illustrate that the minimum concentrations of most trace elements within certain Ordovician formations can be taken as strong evidence for the existence of a well developed karst and a high water-bearing capacity. 展开更多
关键词 ORDOVICIAN trace element water-bearing capacity Damn coal field
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采用电子能量损失谱成像技术对富铬钢的析出相进行综合分析
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作者 ALBU Mihaela MAYR Peter +1 位作者 HOFER Ferdinand KOTHLEITNER Gerald 《冶金分析》 CAS CSCD 北大核心 2012年第12期8-14,共7页
本文采用先进的扫描透射电子显微镜方法,研究含Cr为9%的硼合金化钢在热处理过程和蠕变测试过程中的微观组织的演变规律,并对于硼元素的作用进行了重点探讨。通过扫描透射电子显微镜获得的电子能量损失谱图像能提供具有高的空间和能量分... 本文采用先进的扫描透射电子显微镜方法,研究含Cr为9%的硼合金化钢在热处理过程和蠕变测试过程中的微观组织的演变规律,并对于硼元素的作用进行了重点探讨。通过扫描透射电子显微镜获得的电子能量损失谱图像能提供具有高的空间和能量分辩率的碳、氮、铁、铬、钒的组成定量图(单位为atoms/nm3),这些图包含了丰富的元素信息。对包含在M23(C,B)6颗粒中的MX析出相进行了鉴定,并分析了其中的硼含量。为了识别氮化钒颗粒向复杂的氮化物(改性Z相)的早期转变过程,通过应用二元直方图分析对能量过滤透射电子显微镜(TEM)的元素图谱进行处理。另外,该研究绘制了蠕变检测样品的原奥氏体晶界图,并通过能量过滤透射电子显微镜,电子能量损失和X射线光谱图对析出相进行了鉴别。 展开更多
关键词 微观组织 含铬钢 透射电子显微镜 双电子能量损失谱DualEELS 能量色散X射线光谱仪 元素量化
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