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1.
菊花微量及宏量元素分析   总被引:8,自引:0,他引:8  
用ICP-AES法测定了药用野菊花和抗白菊及6种人工栽培菊花中As,B、Ba、Ca、Cd、Co、Cu、Fe、Mg、Mn、Mo、Ni、Pb、Se、Si、V、Zn、P、S、K等元素的含量。结果表明:(1)菊花中Ca、Mg、P、S、K含量很高,B、Fe、Mn、Zn也有较高的含量;(2)野菊花中B、Ca、Fe、Mg含量较其他品种高、,抗白菊中Mn、Se、S含量高地其他品种;(3)代栽培的菊花K、P含量高于  相似文献   

2.
不同产地高良姜无机元素含量的比较   总被引:6,自引:0,他引:6  
用等离子体发射光谱法测定了三个不同产地高良姜的元素含量,在27种被测元素中,除As、Be、Cr、Mo、Pb、Sb、Tl7种元素未被检出外,三个产地的高良姜均含有Ag、Al、B、Ba、Ca、Cd、Co、Cu、Fe、Mg、Mn、Na、Ni、Se、Si、V、Zn、K、P、S20种元素,湛江产的高良姜大多数元素的含量要高于其它两地。Zn和Mn两种人体必需微量元素的含量较丰富。  相似文献   

3.
电感耦合等离子体光谱和质谱法分析贻贝标准物质   总被引:5,自引:0,他引:5  
采用电感耦合等离子体光谱和质谱法分析了贻贝标准物质,光谱法测定K、Na、Ca、Mg、P、Al、Fe、Zn、Mn和Sr,质谱法测定As、B、Cd、Co、Cr、CuGa、Ge、Mn、Mo、Ni、Pb、Se、Sr、U和V。在优化的工作条件下,测定了来自基体元素K、Na、Ca、P、Cl的C的多原子离子^39K^16O、^39K2、^40Ar^23Na、^43Ca^16O、^42Ca^16O、^31P^16  相似文献   

4.
侯列奇  王树安 《分析化学》1995,23(8):919-921
本法对U3Si中22个微量杂质元素的测定,进行了较系统的实验研究,取样100mg时,Al、Ca、Cd、Cr、Cu、Fe、Hf、In、Mg、Mn、Mo、Nb、Ni、Pb、Sn、Ta、Ti、V、Y、Zn和Zr的测定范围5μg/g-800μg/g,回收率为94%-105%,RSD(n=8)0.4%-1.2%。  相似文献   

5.
用可见分光光度法与等离子体发射光谱法对仙人掌果汁色素及其微量元素的含量进行了测定,仙人掌果汁色素含量达2.1% ̄3.3%,成熟果的果汁色素含量比预成熟果大。在27种被测定的元素中,除As、Be、Cd、Co、Mo、Pb,Sb,Tl等未被检出外,其余Ag,Al,B,Ba,Ca,Cr,Cu,Fe,Mg,Mn,Na,Ni,Se,V,Zn,K,P,S等均有准确测定值。成熟果与预成熟果的果汁微量元素含量无明显  相似文献   

6.
为确认Alloxan发糖尿病鼠与微量元素的关连,用多元分析研究了糖尿病鼠样品中微量元素,并引出对糖尿病的新见解。用ICP-AES测定了Alloxzn诱发糖尿病鼠和对照鼠的骨、心、肾、脾、肺、肝、血和毛中19种微量和宏量元素(Al、As、B、Ba、Cd、Co、Cr、Mg、Mn、Ni、Pb、Se、Zn、Fe、Cu、Sr、Ti、V) ,结果在糖尿病鼠与对照经组的微量元素间呈现一些显著差异。多元分析找到  相似文献   

7.
应用ICP-AES技术测定了Sr,Ca,Mg,P,Fe,Cu,Mn和Zn等8种生命元素在海带中的分布,发现三种分布模式;(1)Fe,Cu,Mn,Zn在叶状体末端和边缘,固着器末端含量高,其余部位含量低;(2)Sr和Ca的分布规律与第一类相似,但固着器基部高于固着器末端;(3)Mg和P均匀分布。  相似文献   

8.
用马氏距离判别法对53例甲状腺肿瘤患者和58例健康人血清中Ba、Cr、Mg、Mn、Mo、Sr、Zn、Fe、Cu和Ca等元素含量进行了分类研究,分类准确度达92.8%。研究结果表明,甲状腺肿瘤病变可能与人体中Mo、Mn、Fe、Mg、Ca和Sr含量异常有关。文中还计算了患者和健康人血清元素间的相关系数,并讨论了其差异性。  相似文献   

9.
给家兔静脉注射不同效阶肝素,并用在子发射光谱仪(DCP-AES)测定兔动脉壁中Mo、Zn、Se、Mn、Al、Cd、Fe、Mg、Ca、Pb、Ni、Ti、Co、K、Na、Li、Cr等元素含量。结果表明,与盐水组比较,商品肝素、低效阶肝素(38u/mg)使Mg、K明显高于(P〈0.05或P〈0.01);低效阶肝素使Zn显著升高(P〈0.05);而商品肝素使Co显著升高,Al显著降低(P〈0.05);两组  相似文献   

10.
应用装有EPM-810Q电子探针扫描分析电镜,对50例乙肝患者头发中Mg、Al、Cd、Ca、Cr、Mn、Fe、Cu、Zn、Pb、Se11种元素含量进行分析,并与健康人头发进行比较。结果表明:乙肝组中Zn含量低于健康组,Cu、Cd、Fe含量高于健康组(P〈0.01)。  相似文献   

11.
《中国化学快报》2020,31(6):1462-1473
Graphene is a two-dimensional nanomaterial with huge surface area,high carrier mobility and high mechanical strength.Because of its great potential in nanotechnology and environmental protection,it has attracted much attention in environmental and energy fields since its discovery in 2004.Although graphene is a star material,many reviews have introduced its use in terms of energy,the research progress in the field of environment,especially water pollution control,has been rarely reported.Here,we review exhaustively the research progress of graphene-based materials in environmental pollution remediation in the past ten years.Firstly,the advantages and classification of graphene were introduced.Secondly,the research progress and main achievements of graphene and its composites in the fields of photocatalytic degradation,pollutant adsorption and water treatment were emphatically described,and the mechanism of action in the above fields was summarized.Finally,we discuss the problems existing in the preparation and summarize the application of graphene in the environment.  相似文献   

12.
大气臭氧化学研究进展   总被引:5,自引:0,他引:5  
贾龙  葛茂发  徐永福  杜林  庄国顺  王殿勋 《化学进展》2006,18(11):1565-1574
臭氧是大气化学中的核心物种。在平流层中,臭氧层可以吸收对生物有害的紫外辐射,对地球生命起保护伞作用。在对流层大气中,适量臭氧对清洁大气是有益的。但是,由于对流层中臭氧前体物排放量的增加,特别是在大城市,产生的高浓度臭氧会对大气环境造成严重污染,对人类、动植物和生态环境具有极大危害。臭氧的研究一般结合外场观测、实验室烟雾箱模拟和计算机数值模拟进行。深入开展大气臭氧化学研究,不仅有助于全面深入理解大气氧化过程以及全面掌握区域乃至全球大气自净能力,而且能为对流层污染控制提供科学依据和方案。本文总结了近年来有关臭氧化学的研究进展,论述了臭氧问题与人类当前面临的一些主要环境问题间的相互关系;重点综述了近年来有关南极臭氧空洞、中纬度地区臭氧低值和北极地区臭氧的损耗机理及其发展趋势;综述了臭氧与大气光化学和气溶胶间的耦合关系,并结合我国实际情况,提出了大气臭氧化学尚待深入开展研究的一些重要科学问题。  相似文献   

13.
Electrodeposited layers of nickel show different growth characteristics depending on the composition of the electrolyte, namely the type of the anion, the presence or the absence of boric acid and the pH. These process parameters are examined in the present work in order to elucidate their influence upon the growth texture and the related surface morphology of the electrodeposits. The relationship between process and structure is investigated by studying the transient electrochemical behavior during deposition, in order to discriminate between different interface conditions corresponding to different growth modes. The observed preferred orientations can be in this way linked to different reactive species, which are assumed to be present at the surface, and to their stability. The correlation between kinetics and structure in nickel electrodeposition reported in the present work and the similar correlation found in cobalt electrodeposition suggest a rationalization of the growth modes of ECD inert metals, based on the correspondence between the transient Tafel parameter and the growth texture observed in defined conditions. Published in Russian in Elektrokhimiya, 2008, Vol. 44, No. 6, pp. 771–783. The text was submitted by the authors in English.  相似文献   

14.
韩广甸  金善炜  吴毓林 《化学进展》2012,24(7):1229-1235
黄鸣龙院士(1898-1979)1919年浙江医药专科学校毕业,1924年德国柏林大学有机药物化学博士;1924-1934年任浙江医专教授、主任,卫生署化学部主任;1934-1940年在欧洲先灵公司等从事研究工作;1940年回国在昆明任中研院化学所研究员,兼任西南联大教授;1945年赴美在哈佛大学,默克公司从事研究工作。1952年绕道欧洲回国,先后在中国人民解放军医学科学院化学系和中国科学院上海有机化学研究所任研究员。1955年当选为中国科学院学部委员(院士)。黄先生一生从事有机化学的教育和研究工作,他在有机化学的“结构与机理”以及“反应和合成”二大方面都作出了在国内外具有深远影响的工作。20世纪40年代黄先生发现了变质山道年4个立体异构体的循环转变,堪称立体化学的经典之作;1948年发表了黄鸣龙还原反应;1952年归国后引领和发展了我国的甾体化学研究,带领了我国甾体药物的生产发展,是我国甾体药物工业的奠基人。黄先生治学严谨,既重视应用研究,又强调基础研究;关注学习新知识、新概念,又更重视实验技术。黄先生教书育人,身体力行,是我国有机化学发展的先驱者和奠基人。  相似文献   

15.
林长缨  丁晓静 《色谱》2020,38(9):999-1012
自1989年出现商品化的仪器以来,毛细管电泳(CE)技术在多个应用领域都取得了长足的进步与发展,重复性和准确性方面也有很大提升。能力验证样品分析的满意结果也显示了CE具备法规要求的准确定量能力。在疾病预防控制领域(简称"疾控")CE也展现出很多独具特色的应用,成为不可或缺的技术之一。在聚合酶链式反应产物分析、核酸序列测定、DNA变异和分型分析、食源性致病微生物分析及疫苗分析等工作中CE发挥了重要作用。应对突发疫情或公共卫生事件如食物中毒时,除了通过非靶标分析尽快锁定目标物外,还需要对大量样品做出快速而准确的分析,高通量和高灵敏的CE就十分适合解决这一问题。在公共卫生理化检验以确保食品、保健食品、特殊医学用途食品、化妆品和消毒产品等的安全中,CE也发挥了不可或缺的作用。作为一种使用较少危险化学品的环境友好方法,在需要按照标准或规范进行的疾控实验室常规检测中,CE仍受制于标准方法的缺失,未能发挥其应有的作用。但简单、快速、经济、耐用、高效的CE分离一旦与高灵敏通用检测器联用,必将更加从容地应对疾控领域中的各种挑战,发挥更大的作用。本文综述了2010~2019年CE在疾控领域的应用,分析了CE在疾控领域发展的机遇和挑战,对CE在疾控领域的发展前景进行了展望。  相似文献   

16.
Abstract

The ICP/MS method with lutetium, bismuth and indium as internal standards was used for the determination of thallium and other elements, i.e. Ti, V, Cr, Ni, Cu, Zn, Rb, Mo, Cd, As and Pb, in soils and rapeseeds. Samples were collected in two thallium highly pedogeochemicaily contaminated areas situated in South Bohemia and in Czech-Moravian Highlands, in two river alluvia, in two control sites with low levels of TI and in one spot with anthropogenic contamination. Levels higher than 2.5 mg kg?1 have been found in rapeseeds in the highly polluted areas (c. 2.8 mg kg?1 in soils). High correlation coefficients, r > 0.81, between content of TI in top- and sub-soils and rapeseeds were obtained. Thallium concentrations exceed twice of Pb content and by one order of magnitude of Cd amounts. This finding are very important because of the high toxicity of TI and the absence of threshold limits for TI in soils, agricultural products and foodstuffs in the Czech Republic.  相似文献   

17.
环境中锑的分布、存在形态及毒性和生物有效性   总被引:42,自引:0,他引:42  
何孟常  万红艳 《化学进展》2004,16(1):131-135
由于自然过程及人类活动的影响,锑及其化合物在环境中普遍存在,环境中锑的污染也日益严重.近年来,国外对锑污染的研究日益重视.锑不是植物必需的,但能够被植物根系吸收.已有证据表明锑对生物及人体产生毒性.本文主要对环境中锑的分布和存在形态,及对动物和人体的毒性和对生物有效性研究进展进行评述。  相似文献   

18.
Density functional theory (B3LYP/6-31G*) is applied to calculate structures, energy, dipole moment, polarizability, frequencies of normal vibrations in the harmonic approximation and intensities in vibrational spectra of 2-, 3-, and 4-biphenylmethanol molecules and their H-complexes that can form in crystalline, amorphous, and liquid phases. Based on the analysis of simulation results, the effect of the position of a methanol group in the molecule on its vibrational spectrum is discussed. The structure forming role of a hydrogen bonds in biphenylmethanols and the possibility of realization of two polymorphic modifications in 2-biphenylmethanol are stated. These modifications are: metastable monoclinic, in which each of four molecules of the unit cell is a link of a chain H-associate; and stable triclinic, in which four molecules of the unit cell organize an H-complex in the form of a cyclic tetramer. It is found that crystalline samples of 3-and 4-biphenylmethanols consist of chain H-associates. A glass-like sample of 2BPhM being a mixture of H-complexes consisting of cyclic tetramers and chain associates contains crystalline nuclei of triclinic and monoclinic polymorphous modifications in the supercooled state. In a liquid sample of 2BPhm, chain H-associates and free molecules are realized.  相似文献   

19.
PanaxquinquefoliumL .belongstothePanaxgenusoftheAraliaceae .ItoriginatesinAmericaandCanada .Itsroots ,afamousandexpensivetraditionalChinesemedicinalmateri al,havebeenstudiedcontinuallysinceitssuccessfulcultivationinChinainthe 1 970’s .Inre centyearsthedevelop…  相似文献   

20.
Nonionic surfactants such as Tween 80 are used commercially to minimize protein loss through adsorption and aggregation and preserve native structure and activity. However, the specific mechanisms underlying Tween action in this context are not well understood. Here, we describe the interaction of the well-characterized, globular protein lysozyme with Tween 80 at solid–water interfaces. Hydrophilic and silanized, hydrophobic silica surfaces were used as substrates for protein and surfactant adsorption, which was monitored in situ, with ellipsometry. The method of lysozyme and Tween introduction to the surfaces was varied in order to identify the separate roles of protein, surfactant, and the protein–surfactant complex in the observed interfacial behavior. At the hydrophobic surface, the presence of Tween in the protein solution resulted in a reduction in amount of protein adsorbed, while lysozyme adsorption at the hydrophilic surface was entirely unaffected by the presence of Tween. In addition, while a Tween pre-coat prevented lysozyme adsorption on the hydrophobic surface, such a pre-coat was completely ineffective in reducing adsorption on the hydrophilic surface. These observations were attributed to surface-dependent differences in Tween binding strength and emphasize the importance of the direct interaction between surfactant and solid surface relative to surfactant–protein association in solution in the modulation of protein adsorption by Tween 80.  相似文献   

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