109 resultados para Massenspektrometrie, CE-ICP-MS, Actiniden


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通过单克隆抗体制备技术得到三株特异结合半抗原 4 ( GSH-S-DNP二苄酯 )的单克隆抗体 HB4 ,HB5和 HB7.抗体经两步化学诱变得到具有细胞谷胱甘肽过氧化物酶 ( c GPX)活性的含硒抗体酶 m HB4 ,m HB5和 m HB7,活力分别为 1 70 ,1 867,32 U/μmol.其中 m HB5的活力是天然兔肝 c GPX的 0 .32倍 ,m 4 A4的1 .51倍 .等离子体 -质谱 ( ICP/MS)测得每分子含硒抗体酶分子中大约存在 2个硒原子 .m HB5的最适 p H为8.6~ 8.8.在 p H值范围为 7.0和 37℃条件下 ,m HB5催化 GSH和 H2 O2 或 t-ROOH反应的二级速率常数为 :k+ 1 ( H2 O2 ) 9.71× 1 0 6 L /( mol· min) ,k+ 1 ( t-ROOH) 5.99× 1 0 5 L/( mol· min) . m HB5使非酶催化反应速率提高了 9.8× 1 0 6和 3.7× 1 0 5倍.

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采用ICP MS、凝胶过滤层析及超滤技术 ,通过动物实验研究了长时间、低剂量镧作用后 ,镧在Wistar大鼠肝脏中的代谢累积及其物种分布。结果表明 ,随着给药剂量的增加及作用时间的增长 ,镧在肝脏中的累积量有规律地增大 ;停止给药一段时间后 ,积累在肝脏中的镧有不同程度的代谢 ,其代谢速度很慢 ;累积在肝脏中的镧主要分布于分子量大于 6 0 0 0 0的水溶性蛋白中 ;经SephacrylS 2 0 0层析分离得到的六个蛋白洗脱峰中均含有稀土 ,在第一个洗脱峰中含量最大 ,约占肝脏含镧大分子蛋白 (分子量大于 6 0 0 0 0 )总量的 88%

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Recent important applications of inductively coupled plasma mass spectrometry in biological samples analysis are reviewed. The sample preparation, sample introduction techniques, interference correction and typical applications are introduced in detail with 154 references.

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介绍了电感耦合等离子体质谱方法在生物样品分析中应用研究的新进展。针对ICP -MS的特点阐述了样品处理、进样方式、干扰校正的主要方法和应注意的问题

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农业中稀土微肥和养殖业中稀土饲料添加剂的普及,使稀土元素大量进入生物循环。从分子水平深入研究稀土元素的生物效应及其作用机理,包括稀土在生物体内的分布、积累、代谢动力学过程及远期毒性等,迫切需要建立生物样品特别是血液样品的快速、灵敏、准确的稀土元素分析方法。电感耦合等离子体质谱法(ICP- MS)已成为痕量稀土测定的首选方法。

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A method for the determiantion of rare earth elements in biological sampels by inductively coupled plasma mass spectrometry was developed. Oxide ion yield of the rare earth elements (RFE) decreased with the increasing of RF power and the sampling depth, or with the decreasing of carrier gas flow rate. The spectral interference arising from (PrO)-Pr-141-O-16 on Gd-157 must be corrected. if the concentration of Ba was high enough, it was necessary to correct the spectral interference arising from (BO)-B-135-O-16 on Eu-151, and it was not necessary to correct spectral interference arising from (NdO)-Nd-143-O-16 on Tb-159 etc. in the biological samples under the selected operation parameters. In the biological sample, the major matrix elements, such as K, Na and Ca, result in the suppression of REEs signals and the suppression degree of the Ca is grezter than that of the K and Na. The mussel sample was digested by thd dry ashing, wet digestion with HNO3 + H2O2 and HNO3 + HClO4, respectively. The analytical results of REEs were consistent with each other. Detection limits for REEs are 0.001 similar to 0.013 mu g/L. Recoveries of standard addition are 91.7% similar to 125%. REEs in biological samples were determined directly without separation and preconcentration procedure.

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A method for the analysis of mussel standard reference material by inductively coupled plasma atomic emission spectrometry( ICP-AES) and inductively coupled plasma mass spectrometry(ICP-MS) was developed. K, Na, Ca, Mg, P, Al, Fe, Zn, Mn and Sr were determined by ICP-AES and As, B, Cd, Co, Cr, Cu, Ga, Ge, Mn, Mo, Ni, Pb, Se, Sr, U and V by ICP-MS, The interference coefficients at the Mn-55, Se-78, Cu-63, Co-59, Ni-58, Ni-60, As-75, Se-77, V-51, Cr-53 and Cr-52 originating from polyatomic ion of the matrix elements (KO)-K-39-O-16, K-39(2), (ArNa)-Ar-40-Na-23, (CaO)-Ca-43-O-16, (CaO)-Ca-42-O-16, (CaO)-Ca-44-O-16, (PO2)-P-31-O-16, (ArCl)-Ar-40-Cl-35, (ArCl)-Ar-40-Cl-37, (ClO)-Cl-35-O-16, (ClO)-Cl-37-O-16 and (ArC)-Ar-40-C-12 were determined under the selected operation parameters. The major matrix elements, such as K, Na and Ca, result in the suppression of analytes signals. The apparent concentration at the significant biological element which was produced by the different digestion methods, (.) HNO3 + H2O2 (3 + 2), HNO3 + HClO4 (3 + 0.5) and HNO3 + H2SO4 (3 + 0.5),was determined. The sample digested by HNO3 + H2O2 did not give rise to interfere on the analyte, and the backgrounds of Se-77, Ga-69, Zn-67, As-75, V-51, Cr-53 and Cr-52 were increased by HNO3 + HClO4 digestion method, that affected the determination of these elements, especially the monoisotope As and V. Sample digested by HNO3 + H2SO4 increased the backgrounds at Cu-65, Zn-64 and Zn-67. Detection limits of ICP-AES are 0.001 similar to 0.75 mg/L and those of ICP-MS are 0.005 similar to 1.01 mu g/L. The relative standard derivations of ICP-AES and ICP-MS are 2.7% similar to 12.8%, 3.4% similar to 24.8%, respectively.

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The content and distribution of rare earth(RE) in normal human plasma have been investigated by ultrafiltration, FPLC and ICP-MS methods, The results showed that there are trace RE in normal human plasma, and their contents are in accordance with their abundance, The RE can bond with immunoglobulin G(IgG), transferrin(Tf) and albumin(Alb) species, but mostly bond with Tf.

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采用ICP-MS及FPLC等技术研究了正常人血浆中稀土含量及其物种分布.结果表明,正常人血浆中含有痕量的稀土(总量为1.413.3μg/L),每种稀土含量与其天然丰度一致;稀土物种主要集中于大分子蛋白组分中,与免疫球蛋白G(IgG)、运铁蛋白(Tf)、血清白蛋白(Alb)等均有作用,其中Tf结合稀土量较多

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利用动物实验、采用ICP MS及NMR技术对稀土离子跨红细胞膜的作用进行了研究 .结果表明 ,给兔一次性注射不同剂量的稀土硝酸盐 ,经不同时间取血 ,在红细胞内没有观察到稀土 .取兔红细胞做体外实验 ,稀土硝酸盐浓度在 0 .0 1mg/mL以下没有观察到稀土离子过膜的现象 ;稀土硝酸盐浓度在 0 .0 1mg/mL以上 ,已有部分红细胞溶血 .并且 ,随浓度增加和温育时间的延长 ,红细胞溶血量也有所增加

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Hydrothermal fluid containing abundant matter erupts from seafloor, meets ambient cold seawater and forms chimneys. So the main matter origins of chimneys are seawater and matter which are taken by hydrothermal fluid from deep reservoir. However, because of seawater's little contribution to the forming of chimneys, it is usually covered by the abundant matter which is taken by hydrothermal fluid. Therefore, chimneys formed in ordinary deep seawater hydrothermal activity, containing complex elements, cannot be used to study the seawater's contribution to their formation. While the native sulfur chimneys, formed by hydrothermal activity near the sea area off Kueishantao, are single sulfur composition (over 99%), and within chimneys distinct layers are seen. Different layers were sampled for trace element determination, with Inductively Coupled Plasma Mass Spectrometry (ICP-MS). By analyzing the data, we consider C-layer (secondary inner-layer) as the framework layer of the chimney which formed early (Fig. 4), and its trace elements derive from hydrothermal fluid. While the trace elements within A, B, D layers have undergone later alteration. A, B layers are affected by seawater and D layer by hydrothermal fluid. The increase of trace elements of A and B layers was calculated using C layer as background. Based on the known typical volume of chimneys of the near sea area off Kueishantao, we calculated the volume of seawater that contributed trace element to chimneys formation to be about 6.37 x 10(4) L. This simple quantified estimate may help us better understand the seafloor hydrothermal activity and chimneys.

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Analyses of rare earth and trace element concentrations of native sulfur samples from the Kueishantao hydrothermal field were performed at the Seafloor Hydrothermal Activity Laboratory of the Key Laboratory of Marine Geology and Environment, Institute of Oceanology, Chinese Academy of Sciences. Using an Elan DRC II ICP-MS, and combining the sulfur isotopic compositions of native sulfur samples, we studied the sources and formation of a native sulfur chimney. The results show, when comparing them with native sulfur from crater lakes and other volcanic areas, that the native sulfur content of this chimney is very high (99.96%), the rare earth element (REE) and trace element constituents of the chimney are very low (Sigma REE < 21x10(-9)), and the chondrite-normalized REE patterns of the native sulfur samples are similar to those of the Kueishantao andesite, implying that the interaction of subseafloor fluid-andesite at the Kueishantao hydrothermal field was of short duration. The sulfur isotopic compositions of the native sulfur samples reveal that the sulfur of the chimney, from H2S and SO2, originated by magmatic degassing and that the REEs and trace elements are mostly from the Kueishantao andesite and partly from seawater. Combining these results with an analysis of the thermodynamics, it is clear that from the relatively low temperature (< 116 degrees C), the oxygenated and acidic environment is favorable for formation of this native sulfur chimney in the Kueishantao hydrothermal field.

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Locating the quantitized natural sediment fingerprints is an important work for marine sediment dynamics study. The total of 146 sediment samples were collected from the Shelf of the East China Sea and five rivers, including Huanghe (Yellow), Changjiang (Yangtze), Qiantang, Ou and Min River. The sediment grain size and the contents of rare earth elements (REEs) were measured with laser particle size analyzer and ICP-MS technology. The results show that absolute REE content (Sigma REE) and the concentration ratio of light REEs to heavy REEs (L/HREE) are different in the sediments among those rivers. There are higher REE contents in being less than 2 m and 2-31 mu m fractions in the Changjiang Estuary surface sediments. The REE contents of bulk sediment are dominated by the corresponding values of those leading size-fractions. Sigma REE of sediment is higher close to the estuaries and declines seaward on the inner shelf of the East China Sea (ECS). The L/HREE ratio has a tendency of increase southward from 28 degrees N. Hydrodynamic conditions plays a predominate role on spacial distributions of the surficial sediment's REE parameters. In some situations, the currents tend to remove the coarser light grains from initial populations, as well as the deposit of the finer heavy mineral grains. In other situations, the currents will change the ratio of sediment constituents, such as ratio between silts and clays in the sediments. As a result, the various values of Sigma REE or L/HREE ratio in different bulk sediments are more affected by the change of size-fractions than source location. Under the long-term stable hydrodynamic environment, i.e., the East China Sea Shelf, new sediment transport model based on the size and density gradation concept may help to understand the spatial distribution patterns of REE parameters.

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台湾东北部的龟山岛位于冲绳海槽向西延伸的部分,其附近海域出现的浅海热液活动,形成了自然硫含量达到99%以上的烟囱体。本文通过使用扫描电镜、X荧光光谱仪、电感耦合等离子质谱仪(ICP-MS)和稳定同位素质谱仪,分析了自然硫样品的表面形貌、常量和微量元素含量,测定了其硫、铅同位素组成以及流体样品中部分元素的含量和氢氧同位素组成。采用燃烧法和升华法对自然硫样品预处理后,进行了样品微量元素测定准确度的对比研究。在上述基础上,探讨了自然硫的物质来源、流体来源和烟囱体生长情况等问题。研究结果表明:龟山岛附近海域的热液活动与火山活动有关,热液流体中的气体组分来自岩浆去气作用;流体经历了海水与大气降水的汇合过程,并在海底下淋滤出部分安山岩的组分;流体喷出海底后,与海水相遇,在有氧环境中,形成自然硫烟囱体,热液流体中所携带的各种元素与海水中的元素随自然硫的形成一起保留在自然硫烟囱体内。

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海水经淡化技术提取淡水后,被浓缩一倍左右的剩余海水被称为高盐度浓海水。日产10万t淡水的海水淡化厂,同时产生10万t以上高盐度浓海水。随着海水淡化规模的迅速扩大,大量浓海水的排放必将对生态环境造成难以估量的威胁。目前,世界各国通常采用浓海水直接排海的方法来处理。这不但威胁了脆弱的生态环境,而且限制了海水淡化事业的发展。同时,海水中大量的化学资源被白白浪费,不符合绿色化学准则与节约资源的要求。研究浓海水资源的综合利用,不但能够缓解浓海水造成的污染,而且能够节约能耗,提高经济效益。 本论文研究了冷冻脱盐法处理浓海水的作用机理,探讨了应用冷冻脱盐工艺技术处理浓海水的效果,研究了不同实验条件下冰冻浓海水的脱盐效率,以及多次分步冷冻处理之后,得到的低盐度冰和高盐度盐水的主要离子组成和性质。并利用ICP-MS对其主要离子含量进行测定。 实验结果表明:离心机转速变化对冰冻浓海水脱盐、脱除钙镁离子的影响显著。不同离心转速条件下,对脱盐和脱除钙镁离子均有较好效果,脱除率均达到88.5%和87.4%以上。随着离心转速的提高,脱盐率提高,转速4000r/min达到最大,但是其变化幅度减小,进一步提高转速对脱盐率和钙镁离子脱除率的提高影响不大。多步冷冻脱盐的实验表明,一次冷冻离心分离,冰晶的盐度可降低99.0%。与原浓海水相比,钾、钠、钙、镁等主要离子含量降低到原浓海水的3%以下。多步离心分离之后,得到的浓盐水的盐度达到原浓海水的3.3倍。通过对微量金属离子含量的分析表明,冷冻脱盐技术对各种微量离子的脱除率不同,如铜的脱除率为94.3%,钴的脱除率为94.8%,铀的脱除率为60.6%。多步冷冻脱盐后,冰融化成水的总量达到被处理的浓海水总体积的2/3以上。