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分光光度法在钢铁元素分析中的应用 被引量:2
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作者 李项军 张向英 《科技资讯》 2009年第27期113-114,共2页
分光光度法测量钢铁元素具有速度快,准确。全文首先介绍了分光光度法与钢铁基本五元素,随后简要分析了分光光度计的组成及其分类。最后提出了分光光度测量钢铁中元素的方法:设计分光光度设计法;试剂前期准备;使用分光光度计进行测试。
关键词 分光光 分光光 元素测定 光吸收度
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Profile of Absolute Light Utilization Efficiency Within Leaves of Euonymus japonicus 被引量:2
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作者 樊大勇 韩涛 +2 位作者 李竟 王强 高荣孚 《Acta Botanica Sinica》 CSCD 2003年第2期169-176,共8页
Absolute light utilization efficiency across leaf section of Euonymus japonicus T. was calculated based on the measurements of photoacoustic technique (PA technique) and microscopic fiber optic probe. This new method ... Absolute light utilization efficiency across leaf section of Euonymus japonicus T. was calculated based on the measurements of photoacoustic technique (PA technique) and microscopic fiber optic probe. This new method was based on the principal of depth analysis by PA technique and the differential analysis of light gradients across leaf section by micro-optical probe technique. The depth analysis was shown by a sample of PA scan light absorption spectra. Results showed that the tissue layers between palisade tissue and spongy tissue used the smallest proportion of incident light energy for photochemical reactions (about 0.026% incident light energy of 660 nm light), while in tissue layer more close to the adaxial surface of leaf or the abaxial surface of leaf, the efficiency of utilization of light energy tended to be improved, e. g. 0.092% for tissue layers close to adaxial surface; 0.036% for tissue layers close to abaxial surface. The results that different leaf tissue layers utilized different proportion of incident light energy for photochemical reaction directly prove the hypothesis put forward by Han and Vogelmann. 展开更多
关键词 depth analysis by PA technique light gradients across leaf section photochemical loss light absorption profile
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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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Determination of Five Metallic Elements in Guoshangye from Guizhou by Microwave Digestion-flame Atomic Absorption Spectrometry
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作者 马四补 王绍辉 +2 位作者 刘同祥 李开斌 陈维 《Agricultural Science & Technology》 CAS 2016年第2期262-264,共3页
In the study, the contents of 5 trace elements including Fe, Cu, Mg, Mn and Ca were directly analyzed by flame atomic absorption spectroscopy in Gu- oshangye. The sample was subjected to microwave digestion with HNO3 ... In the study, the contents of 5 trace elements including Fe, Cu, Mg, Mn and Ca were directly analyzed by flame atomic absorption spectroscopy in Gu- oshangye. The sample was subjected to microwave digestion with HNO3 and H2O2, and detected by the standard curve method. The results showed that Guoshangye contained abundant trace elements which rates of these trace elements were in the curacy and satisfactory. were necessary for human. The recovery range of 96%-103%. The method is ac- 展开更多
关键词 Trace elements Guoshangye Flame atomic absorption spectroscopy
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Preliminary Identification of Red Pigment and Positive Correlation between the Contents of Red Pigment and Total Saponins of Panax notoginseng Fruits 被引量:1
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作者 赵昶灵 陈中坚 +3 位作者 陈文龙 支伟特 魏富刚 宋德功 《Agricultural Science & Technology》 CAS 2012年第9期1891-1895,共5页
[Objective] This study aimed to identify red pigment of Panax notoginseng fruits and explore the correlation between pigment content and total saponins of the fruits. [Method] The red pigment of Panax notoginseng frui... [Objective] This study aimed to identify red pigment of Panax notoginseng fruits and explore the correlation between pigment content and total saponins of the fruits. [Method] The red pigment of Panax notoginseng fruits was preliminarily identi- fied with specific color reactions and UV-vis spectra, and the contents of the pigment and total saponins were determined via spectrophotometry. [Result] The red hues of the fruits were contributed by anthocyanins and/or the anthocyanidins. The contents of anthocyanins and total saponins of the fruits both decreased along with thinning of the red hues. The content difference of the anthocyanins in fruits with different red hues reached extremely significant level, but that of total saponins just reached significant level. [Conclusion] The red pigment of P. notoginseng fruits is anthocyanins which are of extremely significant positive correlation with total saponins in contents. 展开更多
关键词 Panax notoginseng fruits Red pigment Anthocyanins Total saponins Content correlation
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Development of 2D Temperature and Concentration Measurement Method Using Tunable Diode Laser Absorption Spectroscopy 被引量:7
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作者 Yoshihiro Deguchi Daisuke Yasui Akira Adachi 《Journal of Mechanics Engineering and Automation》 2012年第9期543-549,共7页
Exhaust gas temperature is an important factor in NOx, THC and PM emissions of engines. Especially 2D temperature and concentration distribution plays an important role for the engine efficiency. A thermocouple is int... Exhaust gas temperature is an important factor in NOx, THC and PM emissions of engines. Especially 2D temperature and concentration distribution plays an important role for the engine efficiency. A thermocouple is intrinsically a point temperature measurement method and noncontact 2D temperature distribution cannot be attained by thermocouples. Recently, as a measurement technique with high sensitivity and high response, laser diagnostics has been developed and applied to the actual engine combustions. With these engineering developments, transient phenomena such as start-ups and load changes in engines have been gradually elucidated in various conditions. In this study, the theoretical and experimental research has been conducted in order to develop the noncontact and fast response 2D temperature and concentration distribution measurement method. The method is based on a Computed Tomography (CT) method using absorption spectra of water vapor at 1388 nm. It has been demonstrated that the method has been successfully applied to engine exhausts to measure 2D temperature distributions. 展开更多
关键词 2D temperature measurement tunable diode laser absorption spectroscopy CT (computed tomography) engine exhausts.
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Preparation and antimicrobial ability of natural porous antibacterial materials 被引量:4
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作者 董发勤 李国武 +3 位作者 孙志刚 沈刚 冯启明 代群威 《Journal of Central South University of Technology》 EI 2005年第4期370-375,共6页
The liquid ion exchange method, solid salt melt method and dry-wet circulation method were used to prepare natural porous antimicrobial materials with natural minerals, such as zeolite, spilite, palygorskite and montm... The liquid ion exchange method, solid salt melt method and dry-wet circulation method were used to prepare natural porous antimicrobial materials with natural minerals, such as zeolite, spilite, palygorskite and montmorillonite, respectively. Atomic absorption spectrum and X-ray diffraction analysis were carried out to investigate the effects of Ag^+ , Cu^2+ and Zn^2+ on antimicrobial abilities of natural porous minerals, and the effect of preparation method on ion exchange capacity of antimicrobial material, respectively. The results show that for the ion exchange capacity, clay mineral is higher than fibrous mineral, i.e. both zeolite and montmorillonite are higher; the antimicrobial ability of material with Ag^+ is the bests the exchange capacities of materials with Cu^2+ or Zn^2+ are all higher, but the antimicrobial ability of Cu^2+ is better than that of Zn^2+ . 展开更多
关键词 liquid ion exchange solid salt melt dry-wet circulation MINERAL antimicrobial material
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Effect of Se-S Cooperated Application on the Mineral Content and Nutrition Quality of Garlic (Allium Sativum L.) 被引量:1
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作者 Huanxiu Li Changquan Wang +2 位作者 Bing Li Zesheng Yan Yangxia Zheng 《Journal of Life Sciences》 2011年第1期29-34,共6页
Eleven nutrition elements and 5 quality elements of garlic (Allium sativum L.) in different Se, S level and their interaction pot experiments were analyzed by atom absorbing spectrophotometer, titration and fixing s... Eleven nutrition elements and 5 quality elements of garlic (Allium sativum L.) in different Se, S level and their interaction pot experiments were analyzed by atom absorbing spectrophotometer, titration and fixing sulfur method. The mineral elements were analyzed by the Principal Component Analysis and the Factor Analysis on the SPSS 10.0 and three main factors were picked. The results showed that Se, S and Se-S cooperated application enhanced the garlic nutrition quality by increasing mineral nutrition. The garlic Vc was the highest after using higher Se compared middle S level (S 20 mg/kg soil + Se 40 mg/kg soil). Lower Se level compared middle S level (S 40 mg/kg soil + Se 20 mg/kg soil) get the highest garlic abio-Se in all treatments. The garlic organic Se content was the highest after using higher Se compared middle S (S 40 mg/kg soil + Se 40 mg/kg soil). The treatment lower S compared lower Se level get the highest garlic allicin in all treatment. It showed that the fresh eating factor was affected by the element Se. The flavor factor and health care factor were affected by both Se and S. 展开更多
关键词 Garlic (Allium stativum L.) Se-S cooperated application mineral content nutritional quality.
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Spectrophotometer standardization in UV-Vis spectral region
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作者 Alaa-Eldin A Abd-Elmageed Essam M Elmoghazy Fatma Elsharkawy 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第1期40-43,共4页
Ultraviolet-visible(UV-Vis)spectrophotometry is commonly used in analytical laboratories for qualitative and quantitative analyses.To make the data obtained reliable,an experimental instrument must be calibrated.Nat... Ultraviolet-visible(UV-Vis)spectrophotometry is commonly used in analytical laboratories for qualitative and quantitative analyses.To make the data obtained reliable,an experimental instrument must be calibrated.National Institute for Standards(NIS)in Egypt builds up aphotometric method to ensure the competence of absorbance and transmittance to the standard international and national requirements.This paper presents an instrument for UV-Vis measurement,discusses the factors affecting measurement reliability and estabishes the uncertainty model including correspoding measurement parameters. 展开更多
关键词 SPECTROPHOTOMETER STANDARDIZATION ABSORBANCE UNCERTAINTY
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Escamoles Ant Eggs Liometopumapiculatumm Source of Metal Ions for Human Health 被引量:1
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作者 Virginia Melo Concepcion Calvo +2 位作者 Tomas Quirino Susana Macin Ileana Muniz 《Journal of Chemistry and Chemical Engineering》 2013年第6期556-559,共4页
The earth crust is believed to be made of a mass of minerals and is matched by their importance in human life. The human body, depend like other leaving organisms, on several minerals as essential constituents of its ... The earth crust is believed to be made of a mass of minerals and is matched by their importance in human life. The human body, depend like other leaving organisms, on several minerals as essential constituents of its existence. Metal ions in foodstuff are in different chemical forms, as inorganic salts or organic molecules or complexes with other compounds such as proteins, amino acids, enzymes and some vitamins, among others, that play an important role in human health. Entomophagy, insect consumption by several ethnic groups in Mexico as cultural tradition since prehispanic era represent an option for population to obtain the minerals needed by the body to keep a good health. Escamoles ant eggs of the Liometopumapiculatum M genus, much appreciated either at rural communities as well as in urban cities, contain minerals with a favorable effect in human health. The aim of this study was to investigate the mineral composition of Escamoles and the benefits which can provide to the human body. Sampling was at an arid region of the Hidalgo state on April 2012. Minerals in dry basis, determined by atomic absorption spectrophotometry, with the exception of phosphorus content, obtained from a triple acid digested extract and determined colorimetrically. Data of mineral analysis in dry basis of Escamoles were: total minerals 5.92%; Na 0.079%; K 0.075%; Ca 0.097%; P 0.701%; Fe 0.021%; Zn 0.035% Cu 0.009%; Mg 0.998%; Mn 0.002%. Minerals quantify are not equal to total ash contained because not all of them were assess determined. Elements concentration depends not only on the total mineral composition of foodstuff the inorganic or organic form or interaction among metal ions, but also on their availability and avail of them. Minerals in Escamoles ant eggs have a considerable influence in the condition of human health. 展开更多
关键词 Escamoles ant eggs metal ions human health.
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Coherent Interband and Intersubband Dynamics in Terahertz-Driven GaAs Quantum Wells
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作者 MI Xian-Wu PENG Jin-Zhang +1 位作者 LI De-Jun ZHAO He-Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第5X期941-947,共7页
We theoretically investigate the optical absorption spectra and charge density by subjecting a GaAs quantum well to both an intense terahertz (THz)-frequency driving field and an optical pulse within the theory of den... We theoretically investigate the optical absorption spectra and charge density by subjecting a GaAs quantum well to both an intense terahertz (THz)-frequency driving field and an optical pulse within the theory of density matrix. In presence of a strong THz field, the optical transitions in quantum well subbands are altered by the THz field. The alteration has a direct impact on the optical absorption and the charge density. The excitonic peak splitting and THz optical sideband in the absorption spectra show up when changing the THz field intensity and/or frequency. The Autler-Towns splitting is a result from the THz nonlinear dynamics of confined excitons. On the other hand, the carrier charge density is created as wave packets formed by coherent superposition of several eigenstates. The charge density exhibitsquantum beats for short pulses and/or wider wells and is modulated by the THz field. 展开更多
关键词 TERAHERTZ quantum well optical absorption
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Photoabsorption Spectra of Si_n and Si_nO (n ≤ 5)
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作者 AN Fang-Fang ZHANG Hong CHENG Xin-Lu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第4期751-755,共5页
The photoabsorption spectra have been calculated for Sis and SilO (n ≤ 5) clusters using time-dependent density-function theory. Our studies suggest that Sin-1 O clusters are relatively stable than those of corresp... The photoabsorption spectra have been calculated for Sis and SilO (n ≤ 5) clusters using time-dependent density-function theory. Our studies suggest that Sin-1 O clusters are relatively stable than those of corresponding Sis clusters. Moreover, substantial differences are observed among the absorption spectra of different molecules in the energy region (0 - 8 eV). Comparing two different exchange-correlation potentials, local-density and generalized-gradient approximations, both calculated optical spectra present the same spectral feature. 展开更多
关键词 Sin clusters SinO clusters TDDFT photoabsorption spectra
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Mathematical Model of Fiber Optic Temperature Sensor Based on Optic Absorption and Experiment Testing
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作者 HU Yan-ling (Yanshan University, Qihuangdao 066004, CHN) 《Semiconductor Photonics and Technology》 CAS 2001年第1期60-64,共5页
On the basis of analysis on the temperature monitoring methods for high voltage devices, a new type of fiber optic sensor structure with reference channel is given. And the operation principle of fiber optic sensor is... On the basis of analysis on the temperature monitoring methods for high voltage devices, a new type of fiber optic sensor structure with reference channel is given. And the operation principle of fiber optic sensor is analysed at large based on the absorption of semiconductor chip. The mathematical model of both devices and the whole system are also given. It is proved by the experiment that this mathematical model is reliable. 展开更多
关键词 Fiber optic temperature sensor Optic absorption reference channel Mathematical model
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Study of Preservation Status and Dietary Reconstruction in the Human Remains Recovered from Roopkund Lake through Chemical Analysis of Faunal Remains
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作者 Yogambar Singh Farswan Jaibir Singh 《Journal of Chemistry and Chemical Engineering》 2015年第1期15-22,共8页
Present study is carried out in the bone samples collected from Roopkund Lake in district Chamoli Garhwal, Uttarakhand which is located at 5,029 meters from main sea level in between Nanda Ghunghti and Trishuli peak. ... Present study is carried out in the bone samples collected from Roopkund Lake in district Chamoli Garhwal, Uttarakhand which is located at 5,029 meters from main sea level in between Nanda Ghunghti and Trishuli peak. This historical site belongs to 9th century A.D. All the samples selected for the study were dried in room temperature as well as hot air oven at 32 ~C. Cleaning, pretreatment and digestion process of faunal remains was followed through established scientific methods. Chemical analysis i.e. concentration of different elements such as calcium, strontium, barium, magnesium and zinc as well as isotopic ratios of Carbon and Nitrogen was estimated with the help of ICP (inductively coupled plasma spectroscopy) and AAS (atomic absorption spectrophotometer). The results obtained from the chemical analysis are significant. On the basis of concentration of different elements and ratios of Nitrogen and Carbon isotopes, the dietary habits of the peoples buried in the Roopkund Lake are identified, which is different from sample to sample person to person. Besides this, the results are also significantly helpful for knowing the preservation status of faunal remains in Roopkund Lake. Finally this study also indicated the potentiality of chemical analysis for reconstructing the palaeodiet behaviour and preservation status of bone remains. 展开更多
关键词 Roopkund Lake dietary reconstruction chemical analysis faunal remains archaeological site.
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Time-Dependent Density-Functional Calculations for Optical Spectra of Na2 and Na4 Clusters
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作者 ZHANG Yan-Ping ZHANG Feng-Shou +1 位作者 MENG Ke-Lai XIAO Guo-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第5期901-904,共4页
With the frame of the time-dependent local density approximation, an efficient description of the optical response of clusters has been used to study the photo-absorption cross section of Na2 and Na4 clusters. It is s... With the frame of the time-dependent local density approximation, an efficient description of the optical response of clusters has been used to study the photo-absorption cross section of Na2 and Na4 clusters. It is shown that our calculated results are in good agreement with the experiment. In addition, our calculated spectrum for the Na4 cluster is in better agreement with experiment than the GW absorption spectrum. 展开更多
关键词 time-dependent local density approximation optical response of cluster
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Acid volatile sulfide and simultaneously extracted metals in superficial sediments from Baihua Lake, China
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作者 章吉萍 胡继伟 +4 位作者 黄先飞 沈威 金梅 付丽亚 靳小飞 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第5期1079-1087,共9页
The bioavailability of five divalent cationic heavy metals (Pb, Cd, Cu, Zn and Ni) in 10 superficial sediment samples from Baihua Lake was assessed based on the molar ratio of simultaneously extracted metals (SEMs... The bioavailability of five divalent cationic heavy metals (Pb, Cd, Cu, Zn and Ni) in 10 superficial sediment samples from Baihua Lake was assessed based on the molar ratio of simultaneously extracted metals (SEMs) to acid volatile sulfide (AVS). Atomic absorption spectrometry (AAS) and X-ray powder diffraction (XRD) were used to determine the heavy metal concentrations and examine the mineralogy of the crystalline phases, respectively. The AVS loadings in sediments from Baihua Lake ranged from 64.30 to 350.08 ~rnol/g (dry weight). The corresponding SEM levels for the sampling sites varied from 1.770 to 14.660 vrnol/g. The molar ratio of SEMs to AVS ranged from 0.014 to 0.084 with a mean value of 0.034. The XRD analysis also confirmed the presence of some metal sulfides in sediments from Baihua Lake. The SEMs/AVS ratios for all sampling sites were significantly lower than 1.0, indicating that AVS in the sediments was sufficient to bind the five heavy metals; thus, these heavy metals are currently not significantly bioavailable to benthic organisms. Comparing the SEMs results to published guideline values for metal toxicity to benthic organisms in sediments, however, suggests that Zn and Ni pose a risk at some sampling locations in Baihua Lake. 展开更多
关键词 Baihua Lake SEDIMENTS acid volatile sulfides simultaneously extracted metals BIOAVAILABILITY
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Spectrophotometric Error Due to Uncertainty in Reading the Signal
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作者 Mavroudis A. Demertzis Anastasios I. Palios Alexandru V. Calin Cristina-Ioana M. Vijdeluc George A.Chrysafis 《Journal of Chemistry and Chemical Engineering》 2012年第7期585-590,共6页
Based upon the standard deviations for the intercept and the slope of a linear regression line, as well as by differentiating both Beer's law and a linear relationship between transmittance and concentration at high ... Based upon the standard deviations for the intercept and the slope of a linear regression line, as well as by differentiating both Beer's law and a linear relationship between transmittance and concentration at high transmission, it is proved that the relative spectrophotometric error of a measurement becomes greater as the sample concentration only decreases. Further, it is demonstrated that the present knowledge with regard to the error in absorption spectrophotometry is necessary to be reexamined. The total scale of transmittance can literally be used for measurements, unfolding workable dynamic ranges about two orders of magnitude lower than usually and thus absorption spectrophotometry can efficiently compete with other methods of analysis with respect to detection limits. 展开更多
关键词 Spectrophotometric error transmittance uncertainty sensitive spectrophotometry transmittance noise.
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Infrared emissivity of transition elements doped ZnO
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作者 姚银华 曹全喜 《Journal of Central South University》 SCIE EI CAS 2013年第3期592-598,共7页
Infrared emissivity was studied in Zno.99Mo.olO (M is Mn, Fe or Ni) and Znl_xCoxO (x=0.01, 0.02, 0.03 and 0.04) powders synthesized by solid-state reaction at various temperatures. XRD patterns confirm the wurtzit... Infrared emissivity was studied in Zno.99Mo.olO (M is Mn, Fe or Ni) and Znl_xCoxO (x=0.01, 0.02, 0.03 and 0.04) powders synthesized by solid-state reaction at various temperatures. XRD patterns confirm the wurtzite structure of the prepared samples. No peaks of other phases arising from impurities are detected in Mn- and Co-doped ZnO, hut the peaks of ZnFe204 and NiO are observed in Zno.99Feo.010 and Zno.99Nio.o10. The SEM observations indicate that with larger grain sizes than those of Zn0.99Feo.010 and Zno.99Ni0.010, Co-doped ZnO exhibits smooth grain surfaces. The infrared absorption spectra show that infrared absorptions related to oxygen in Zn0.99M0.010 are much stronger than those in Co-doped ZnO. Co ions are dissolved into the ZnO lattice with Co2+ state from XPS spectra analysis. The infrared emissivity results imply that the emissivity of Zno.99Ni0.010 is the highest (0.829) and that of Zno.99C00.010 is the lowest (0.784) at 1 200 ℃. The emissivity of Zno.99Co0.010 decreases to the minimum (0.752) at 1 150 ℃ and then increases with growing calcination temperature. As the Co doping content grows, the emissivity of Co-doped ZnO calcined at 1 200 ℃ falls to 0.758 in the molar fraction of 3% and then ascends. 展开更多
关键词 solid-state reaction transition element doping infrared absorption spectrum infrared emissivity
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Theoretical Studies on the Ground State and Excited State of 2,7′- (Ethylene)-bis-8-hydroxyquinoline
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作者 Hui-xue Li Su-juan Pan +1 位作者 Xiao-feng Wang Tai Xiao 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第3期263-269,共7页
2,7′-(Ethylene)-bis-8-hydroxyquinoline was optimized with DFT/B3LYP and ab initio HF methods, so ion- ization potential and electron affinity could be determined. Absorption spectrum was calculated by ZINDO and TD-... 2,7′-(Ethylene)-bis-8-hydroxyquinoline was optimized with DFT/B3LYP and ab initio HF methods, so ion- ization potential and electron affinity could be determined. Absorption spectrum was calculated by ZINDO and TD-DFT. CIS method was used to calculate the S1 excited states of the compound and afterwards the emission spectrum was computed. When the solvent effect was taken into account, the computed results show encouraging agreement with known experimental data. The results of analyzing the relationship between the energies and absorption spectra indicate that the ability to transporting electrons is strengthened compared with 8-hydroxyquinoline and that absorption and emission spectra are red-shifted. The intramoleeular reor- ganization energy of tris(2,7′-(ethylene)-bis-8-hydroxyquinoline)-aluminum implies its electron transporting property is worse than tris(8-hydroxyquinoline)-aluminum. The predicted maximum emission wavelength is red-shifted compared with tris(8-hydroxyquinoline)-aluminum. 展开更多
关键词 2 7′(Ethylene)-bis-8-hydroxyquinoline Absorption spectrum Emission spectrum Densityfunctional theory
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Low Blood Lead Concentrations and Cognitive Development of Primary School Children from Three Areas in Malaysia
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作者 H. Zailina R. Junidah +2 位作者 M.E. Saliza B.S. Shamsul H.H. Jamal 《Journal of Environmental Science and Engineering》 2011年第4期493-499,共7页
A study on to identify the relationship between blood lead and cognitive development was conducted on primary school children in Malaysia. About 413 children aged 62^/1 - 82^/1 years from urban (236), rural (80) a... A study on to identify the relationship between blood lead and cognitive development was conducted on primary school children in Malaysia. About 413 children aged 62^/1 - 82^/1 years from urban (236), rural (80) and industrial areas (97) were studied. Blood lead was analyzed using the Atomic Absorption Spectrophotometer (GFAAS). Cognitive development was measured by the 'McCarthy Scales of Children's Abilities Test' (MSCA). Significant differences found in the mean cognitive scores between the urban (94.40), industrial (102.90) and suburban children (101.24) (p 〈 0.001), with the blood lead between the urban (3.66 p.g/dL), industrial (3.54 μg/dL) and suburban children (3.04μg/dL) (p = 0.022). Significant inverse correlations between blood lead and cognitive scores found for all groups (p 〈 0.001), urban (p 〈 0.001) and suburban children (p 〈 0.001). Low blood lead significantly influenced the cognitive development for all children after adjusting for confounders (p _〈 0.001). The urban children's cognitive scores were significantly influenced by blood lead levels and household income (p 〈 0.001). However, for the suburban children, the cognitive score were significantly influenced by the blood lead levels, the mothers' education, number of siblings, sequence in the family and the household income (p 〈 0.001 ). Blood lead below 10μg/dL influenced the cognitive development. Urban children had higher blood lead but suburban children with lower blood lead were also vulnerable to the effect of lead on their cognitive development. 展开更多
关键词 Low blood lead school children cognitive development.
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