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1.
我国稀土生物无机化学研究进展   总被引:22,自引:3,他引:22  
我国稀土生物无机化学研究的特点是紧密结合稀土在农用及药物中应用所提出急需回答的问题, 经过长期的工作, 已在稀土的跨细胞膜运转, 稀土进入动物体内后的物种分布, 稀土与细胞膜的作用, 稀土对血红蛋白结构与载氧功能的作用, 稀土对骨细胞及骨结构的影响以及稀土在大鼠肝脏中的积累等方面取得了满意的结果. 从而可以为今后开展稀土元素在农用及药用中危险性评价的基础数据, 同时亦将促进稀土细胞化学的发展.  相似文献   

2.
本研究进行富稀土金针菇和农用硝酸稀土对小鼠生长、发育及耐力的对比试验。结果表明,饲喂富稀土金针菇的小鼠,三周后体脏重及耐力均显著高于无稀土的金针菇对照组(E组),且表现出一定的剂量效应。与饲喂硝酸稀土的小鼠(D组)相比,当添加的稀土量相等时,饲喂富稀土金针菇的小鼠(B组)体重和脏器重明显增加,游泳时间延长28.6%,游泳后B组血乳酸含量的变化明显低于C、D、E组,血糖含量下降率较小。可见,将适量富  相似文献   

3.
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  相似文献   

4.
我国稀土资源得天独厚,拥有量世界第一,占世界储量的40%以上,且矿藏分布广、元素种类齐全.稀土元素因其独特的4f亚层电子结构,表现出十分丰富的光、电、磁、催化等性质,被誉为"新材料的宝库".稀土元素已经被美国和日本等发达国家列为战略元素,在战略性新兴产业及与人类社会生活密  相似文献   

5.
稀土对血红蛋白载氧功能的抑制及与血红蛋白的作用   总被引:6,自引:0,他引:6  
实验表明稀土离子可一定程序地抑制血红蛋白在低发压时释放氧的功能;所有稀土离子可导致血红蛋白和血红素辅基的荧光发射增强,使血红蛋白的α-螺纹旋含量减少和引起二级结构和构象的改变;稀土离子还可能干扰珠蛋白部分和血红素辅基正常的相互作用。  相似文献   

6.
稀土对肝脏作用的机制   总被引:14,自引:1,他引:14  
综述了稀土对肝脏作用的机制,稀土不仅能引起肝脏形态学的改变,当稀土进入肝细胞后可与多种蛋白质等分子发生相互作用,并影响多种酶的活性,还能通过信使分子干扰肝脏正常的生理功能。  相似文献   

7.
稀土与细胞,器官,组织的作用及其生理效应   总被引:52,自引:0,他引:52  
稀土与细胞、器官、组织的作用及其生理效应杨频,魏春英(山西大学分子科学研究所,太原,030006)我国稀土贮量占世界第一位,稀土微肥已被大面积使用,稀土已进入植物,如在玉米大豆中,稀土含量为10(-8)~10(-10)g/g[1]。随着稀土的广泛应用...  相似文献   

8.
合成了Pr、Yb的苯磺酰化甘氨酸配合物,观测了它们对水稻幼苗初期生长的影响以及对油菜种子萌发和幼苗生长情况。结果表明,适宜含量的该类配合物可促进种子萌发的启动,并对种苗根系和幼苗的生长有明显促进作用,并以2.5×10-6~5.0×10-6含量范围效果最佳。  相似文献   

9.
用核磁共振(NMR)方法研究了稀土离子及其配合物与二棕榈酰磷脂酰胆碱(DPPC)和鞘磷脂(SPM)脂质体的相互作用.磷脂极性头平行于膜平面.稀土离子与磷脂极性头P—O键键合,与经典模型不同,键合后极性基团仍平行于膜平面,而不是垂直于膜平面.稳定的稀土配合物对磷脂脂双层结构影响很小.将稀土离子引入磷脂脂质体和小分子配体的混合物中,稀土首先与小分子配体配位.  相似文献   

10.
稀土掺杂上转换纳米粒子(RED-UCNPs)作为一种新型高效的上转换发光纳米材料,具有反斯托克斯位移大,发射光谱窄、发光寿命长、材料毒性低等优点,已成为荧光标记、光动力学治疗、生物成像和构建生物传感器等领域的研究热点。然而,目前广泛使用的溶剂热法合成的RED-UCNPs生物相容性和亲水性差,而且不具备与生物分子之间相偶联的活性基团,因此对RED-UCNPs进行表面功能化修饰就显得格外重要。本文重点综述了RED-UCNPs的表面功能化修饰的类型及其应用现状,为RED-UCNPs的进一步研究开发和应用提供思路和参考依据。  相似文献   

11.
利用高纯铜粉与稀土矿石粉末均匀混合压片制样.混合15种高纯稀土氧化物制样建立标准工作曲线,校正15种稀土元素相对灵敏度因子,再进行定量分析.结果 表明,稀土元素工作曲线的线性方程相关系数R2均大于0.996,相对标准偏差(RSD)小于5%,满足定量分析要求.测定结果与电感耦合等离子体质谱法(ICP-MS)和电感耦合等离...  相似文献   

12.
The determination of rare earth elements (REEs), Au, Pt, Ir, Pd, Th and U in various river species was performed by the orthogonal time-of-flight inductively coupled plasma mass spectrometry (o-TOF-ICP-MS). The method working conditions were optimised in order to minimise the presence and possible spectral interferences of oxides. Ratios MO+/M+ as well as interference of light REE and Ba oxides/hydroxides with high REEs were evaluated and confirmed to be insignificant. Using the internal standard Re, non-spectral matrix effects (originally decreasing of intensities up to 15%) were overcome and recoveries were found from 92 to 105% for all matrices analysed. For solutions, limits of detection (3σ) were 0.14–0.82 for REEs, Th, U and Y, 1.18 for La, 4.3–5.6 for Au, Pt, Ir and Pd 11 for Sc (all in ng L?1). The Principal component analysis was used for classification of samples according to their places of origin successfully. The o-TOF-ICP-MS was proved to be a very sensitive and suitable technique for bio-monitoring purposes and was employed in the analysis of biota samples (fish, insect, profiles, benthal growths) originated from five different places in the river Elbe (Czech Republic).  相似文献   

13.
开滦煤洗选过程中稀土元素的迁移和分配特征   总被引:5,自引:1,他引:5  
以河北开滦矿区晚古生代煤及其洗选产品为研究对象,运用电感耦合等离子体质谱(ICP-MS)和逐级化学提取的方法,对稀土元素的质量分数及其在洗选过程中的迁移和分配特征进行了研究。结果表明,开滦矿区煤中稀土元素没有明显富集;稀土元素在入洗原煤及其洗选产品中,以煤泥中质量分数最高,尾煤次之,在尾煤和煤泥中均相对富集;稀土元素在精煤中的质量分数最低;同原煤相比,中煤的稀土元素质量分数没有明显变化。原煤及其洗选的4种产品中的稀土元素分配模式基本相同,主要差别是质量分数的不同。稀土元素在洗选过程中的分配行为和赋存状态主要受控于黏土矿物,其次是有机质。  相似文献   

14.
桦甸油页岩中稀土元素赋存状态研究   总被引:3,自引:0,他引:3  
以吉林省桦甸油页岩为研究对象,采用电感耦合等离子质谱( ICP-MS)和化学逐级提取方法相结合,对油页岩中稀土元素的分布特征以及油页岩中稀土元素的赋存状态进行研究.结果表明,相对于中国煤,桦甸油页岩表现为轻稀土元素富集程度高于重稀土元素.油页岩中稀土元素与陆源碎屑岩关系密切,且陆源物质的供应相对比较稳定.轻重稀土间分馏...  相似文献   

15.
Energy-adjusted pseudopotentials for the rare earth elements   总被引:1,自引:0,他引:1  
Nonrelativistic and quasirelativistic energy-adjusted pseudopotentials and optimized (7s6p5d)/[5s4p3d]-GTO valence basis sets for use in molecular calculations for fixed f-subconfigurations of the rare earth elements, La through Lu, have been generated. Atomic excitation and ionization energies from numerical HF, as well as SCF pseudopotential calculations using the derived basis sets, differ by less than 0.1 eV from numerical HF all-electron results. Corresponding values obtained from CI(SD), CEPA-1, as well as density functional calculations using the quasirelativistic pseudopotentials, are in reasonable agreement with experimental data.  相似文献   

16.
A novel method based on gaseous compounds introduction into the plasma as their pivaloyltrifluoroacetone (PTA) chelates was developed for electrothermal vaporization inductively coupled plasma mass spectrometry determination of trace rare earth elements (REEs) in natural water. The factors affecting formation of the chelates and their vaporization behaviors were studied in detail. Under the optimized conditions, the limits of detection (3σ) of REEs for this method were from 0.20 to 0.91 ng L−1, the relative standard deviations for 0.1 μg L−1 REEs were 2.5–9.1% (n = 9), and the linear ranges of calibration curve for REEs covered at least three orders of magnitude. The proposed method had been applied to the determination of trace REEs in water samples of Yangtze river, Han Shui river and East lake (Wuhan), and the recoveries for the spiked water samples were 93–105%.  相似文献   

17.
Solid sample introduction into an ICP-MS by laser ablation is an effective method for the total analysis of rare earth elements (REEs) in soils because no digestion is needed. A problem of the method, however, is the difference of the ablated mass for each laser shot. Therefore, internal standard for the compensation of signal instability, sample preparation, and the calibration method have to be carefully chosen.The analyzed sample was a certified standard provided by IAEA (SOIL-7). The sample was mixed with an internal standard solution and polyethylene (PE), dried, homogenized in a ball-mixer/mill, and pressed to a pellet. For the calibration 5 external standards with increasing REEs concentrations (0.4–20 g/g) as well as a blank were prepared in the same way.The analysis of the pellets was performed on a VG PlasmaQuad II + with a LaserLab unit. The laser ablation-cell was modified to improve the sample particle transportation characteristics and to allow a quicker sample-exchange. The pellets were ablated from six different spots for 60 s each with a laser-repetition rate of 4 Hz.The correlation coefficients of the calibration curves based on 5 standards, were better than 0.995. The concentrations cA of the 15 REEs in the soil sample were determined with an average relative confidence interval 100(CI)/cA of 6.95%, as a figure for the precision. This good precision have been obtained with a new laser ablation cell, which will be described in detail.With 2 exceptions (Ce and La) the measured concentrations were within the confidence intervals (CI) of the certified values. Therefore, with respect to accuracy and precision, the presented method offers a convenient way to analyze homogeneous and powdered soil samples for REE's without digestion. Since a good calibration for the REE determination may be obtained, the laser sampling variance (within the sample) is less significant than the analytical variance. Automation of the method is possible by construction of an autosampler based on the modified laser cell.Presented in part at the 1993 European Winter Conference on Plasma Spectrochemistry, Granada, Spain  相似文献   

18.
Rare earth elements (REEs) have been widely applied in modern industry and material science due to their special chemical properties and luminescence properties, but their environment pollution problem has also attracted attention. How to trace and control impact of REEs on environment and develop highly sensitive methods for REEs analysis have practical significance. Microwave plasma torch (MPT) is a kind of simple, low power consumption (~200 W) and easily operated plasma generators. When it was coupled with varied mass spectrometers as ion source of mass spectrometry (MS), i.e. MPT-MS can use for the analysis of metal elements in aqueous with the remarkable advantage of only minimal or even no simple pretreatment, and can meet comprehensive requirements of environmental control and water quality monitoring. MPT-MS have also an ability to carry out online real-time monitoring and analysis of water environment. Compared with the traditional ICP-MS, it can obtain more effective information and has higher sensitivity (the detection limit is at sub-ppb level). This paper reviews common methods and research progress of REEs analysis in recent years. Practical applications and advantages of MPT in the analysis of REEs are briefly summarized. Specifically, this paper introduces some work recently done in our group on analysis of REEs by the MPT, including analysis of metal elements distribution in water samples in local Poyang Lake, and general rules of formation and behavior of complex metal ions in the MPT plasma are also proposed afterwards. Through the practically dealing with the Poyang Lake case by the MPT, hopefully this would interest more academia into this area so as to speed up development of the MPT itself.  相似文献   

19.
Journal of Thermal Analysis and Calorimetry - The rare earth element 2-naphthoates were prepared as crystalline solids sparingly soluble in water (10?5?10?6 mol·dm?3),...  相似文献   

20.
采用微波消解前处理方法,结合电感耦合等离子体质谱技术,建立了板栗中钠(Na)、钾(K)、镁(Mg)、锰(Mn)、铁(Fe)、钒(V)、钴(Co)等19种矿物元素及镧(La)、铈(Ce)、镨(Pr)、钕(Nd)、钐(Sm)、铕(Eu)、钆(Gd)、铽(Tb)、镝(Dy)、钬(Ho)、铒(Er)、铥(Tm)、镱(Yb)、镥(Lu)、钇(Y)等15种稀土元素的同时分析测定方法。该方法检出限为0.0027~0.78μg?L-1,相对标准偏差为1.4%~6.3%。通过国家标准物质GBW10019苹果的准确率实验验证,测定结果均在标准证书值范围内。实验结果表明,该方法适用于板栗中矿物元素及稀土元素的同时测定。  相似文献   

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