172 resultados para Dosimetri LiF:Mg,Cu,P Taratura


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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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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、Nn和Sr,质谱法测定As、B、Cd、Co、Cr、Cu、Ca、Ce、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和C的多原子离子~(39)K~(16)O、~(39)K_2、~(40)Ar~(23)Na、~(43)Ca~(16)O、~(42)Ca~(16)O、~(44)Ca~(16)O、~(31)P~(16)O_2、~(40)Ar~(37)Cl、~(35)Cl~(16)O、~(37)Cl~(16)O和~(40)Ar~(12)C对~(55)Mn、~(78)Se、~(63)Cu、~(59)Co、~(58)Ni、~(60)Ni、~(75)As、~(77)Se、~(51)V、~(53)Cr和~(52)Cr的干扰系数以及HNO_3+H_2O_2(3+2)、HNO_3+HClO_4(3+0.5)和HNO_3+H_2SO_4(3+0.5)等3种样品消解方法在一些生物重要元素的同位素处产生的表观浓度。光谱法的检出限0.001~0.75mg/L;质谱法的检出限0....

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Hydrotalcite-like compounds (HTLcs): CoMAlCO3-HTLcs (M=Cu2+, Ni2+, Mn2+, Cr3+, Fe3+), were synthesized by coprecipitation and characterized with XRD and IR. The catalysis of these HTLcs and their calcined products were studied in the p-cresol oxidation, and the effects of the temperature of HTLcs calcination, the ratio of Co/Cu, different promoters, reaction temperatures and reaction times on reaction activities were investigated. It has been found that calcined HTLcs have higher activity than uncalcined samples and mechanical mixed oxides in this reaction. The best yield was obtained from the CoCuAlCO3-HTLc (Co/Cu/Al=3:1:1) calcined at 450 degrees C. A tentative reaction mechanism was also proposed. (C) 1998 Elsevier Science B.V.

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With XRD, R-T, and ac chi measurements a comparative study on the doping effects of 3d elements in Bi(1.5)Pb(0.2)Sr(2)Ca(2)Cu(2.8)M(0.2)O(y) (M = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, or Zn) has been carried out. The effects of the former five members are significantly different, both on phase formed and on T-c, from the latter four. It seems that the effect on phase stabilization correlates with the valency of the doped cation. In connection with the instability of the 2223 phase, the correlation has been discussed.

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检测10种外眼病141例、178眼泪液中的Ca、Mg、Zn、Fe含量。结果显示,翼状胬肉和泡性角结膜炎泪液中的Ca,复发单疱病毒性角膜炎(HSK)泪液中的Ca、Mg、Zn、Fe,慢性结膜炎泪液中的Ca、Fe含量均明显低于对照组(P<0.001~0.05)。提示这4种外眼病的病因可能与泪液Ca、Mg、Zn、Fe含量不足有关。

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In order to avoid the hygroscopicity of LiCl specimem, the method of directly chlorinating Li_2CO_3 with NH_4Cl was successfully introducing into the thermal analysis of the system containing LiCl. The three fusibility diagram of LiCl-KCl, LiClNaCl, LiCl-LiF were determined using the method. The results are in agreement wish the values reported in the literature, and phase diagram of LiCl-KCl-LiF ternary system was constructed based on these results. Temperature of the ternary eutectic, composed of 57.3mol%...

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Effects of various concentrations of two heavy metals, namely Cd and Cu, on gametophytes of Laminaria japonica Aresch were determined by recording morphological changes of gametophytes, determining pH values and the heavy metal content of the culture solution, calculating the germination rate of sporophytes, and observing heavy metal (Cd) distribution using a fluorescence microscope. The results showed that heavy metals damaged the gametophytes, and were even lethal, and that the higher the concentration of heavy metal ions, the greater the injury to gametophytes. Gametophytes could not survive in culture solutions containing more than 100 mg/L Cd and 50 mg/L Cu and were only able to survive in culture solution containing a mixture of Cd and Cu tip to a concentration of 10 mg/L, which indicates that gametophytes have a higher tolerance to Cd than Cu and that multiple heavy metal ions in solution markedly aggravate the damage to gametophytes compared with individual heavy metal ions. With increases in the concentration of the heavy metal, the burgeoning rate of sporophytes decreased acutely, and solutions containing multiple heavy metal ions caused even more marked harm to sporophytes than solutions containing a single heavy metal ion, because most sporophytes died in mixed solutions. The pH value of the culture medium dropped immediately at the beginning (the first day) of treatment, increased over the following days, and then decreased again. The pH of culture media containing multiple heavy metal ions showed greater variation than media containing a single heavy metal ion, with the extent of the decrease in pH of culture media containing multiple ions being greatest during the last period of the experiment. With increases in the concentration of heavy metals, the capacity of gametophytes to accumulate these ions increased. The blue fluorescent light emitted by the Cd- and Cd-binding protein complex existing in gametophytes in media containing different concentrations of Cd showed clearly the distribution of the ion in gametophytes and the results obtained were consistent with distribution determined using other methods. All results of the present study showed that gametophytes of L. japonica play a remarkable role as heavy metal decontaminators, especially with regard to Cd.

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The mineralogical and geochemical characteristics of Fe-oxyhydroxide samples from one dredge station (long. 103 degrees 54.48'W, lat. 12 degrees 42.30'N, water depth 2655 m) on the East Pacific Rise near lat 13 degrees N were analyzed by XRD, ICP-AES, and ICP-MS. Most Fe-oxyhydroxides are amorphous, with a few sphalerite microlites. In comparison with Fe-oxyhydroxides from other fields, the variable ranges in the chemical composition of Fe-oxyhydroxide samples are very narrow; their Fe, Si, and Mn contents were 39.90%, 8.92%, and 1.59%, respectively; they have high Cu (0.88%-1.85%) and Co (65x10(-6)-704x10(-6)) contents, and contain Co+Cu+Zn+Ni > 1.01%. The trace-element (As, Co, Ni, Cu, Zn, Ba, Sr) and major-element (Fe, Ca, Al, Mg) contents of these samples are in the range of hydrothermal sulfide from the East Pacific Rise near 13 degrees N, reflecting that this type of Fe-oxyhydroxide constitutes a secondary oxidation product of hydrothermal sulfide. The Fe-oxyhydroxide samples from one dredge station on the East Pacific Rise near 13 degrees N are lower in Sigma REE (5.44x10(-6)-17.01x10(-6)), with a distinct negative Ce anomaly (0.12-0.28). The Fe-oxyhydroxide samples have similar chondrite-normalized rare-earth-element (REE) patterns to that of seawater, and they are very different from the REE composition characteristics of hydrothermal plume particles and hydrothermal fluids, showing that the REEs of Fe-oxyhydroxide are a major constituent of seawater and that the Fe-oxyhydroxides can become a sink of REE from seawater. The quick settling of hydrothermal plume particles resulted in the lower REE content and higher Mn content of these Fe-oxyhydroxides, which are captured in part of the V and P from seawater by adsorption. The Fe-oxyhydroxides from one dredge station on the East Pacific Rise near 13 degrees N were formed by secondary oxidation in a low temperature, oxygenated environment. In comparison with the elemental (Zn, Cd, Pb, Fe, Co, Cu) average content of hydrothermal sulfide samples from the East Pacific Rise near 13 degrees N, the Zn, Cd, and Pb contents of the Fe-oxyhydroxides are lower, and their Fe, Co, and Cu contents are higher.

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Detritus, as a nutrients reservoir, affects the trophic structure and dynamics of communities and supports a greater diversity of species and longer food chains. Detritivorous fish is an important organism to regenerate the nutrients from sediments. Despite the numerous studies on the nutrients cycle in fish, only a few attempts have been made to quantify the regenerating ability. In the present study, we chose the common detritivorous fish redeye mullet as the research object. Redeye mullet is also a common poly-culture fish in China. Diet, including a commercial diet mostly used in aquaculture and a home-made diet with contents close to detritus, was used and considered as a fixed factor. Temperature was also considered as a fixed factor as much research has shown that temperature has significant effects on fish metabolism. Moreover, body size was regarded as a covariate under analysis of covariance. Three key nutrients, namely carbon, nitrogen and phosphorus, were used to measure the nutrient-regenerating ability of redeye mullet under laboratory conditions. The results showed that the nutrient regeneration in percent of the consumption decreased with increasing temperature. Carbon and nitrogen regeneration of redeye mullet fed on commercial diet was lower than those of the home-made diet group, while the opposite was found for phosphorus. In each group, the amount of regenerated nutrients increased linearly with body size. Fed on the home-made diet, 5-g fish at 25 degrees C can regenerate 210.822 mg C, 37.533 mg N and 0.727 mg P per day.

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对藏药材白花龙胆花中17种微量元素(Cu、Zn、Fe、Mn、Co、Ni、Se、Cr、Mg、Ca、K、Na、P、As、Hg、Pb、Cd)的含量作了测定。结果表明,白花龙胆花中含有较高的人体必需微量元素和常量元素,其中常量元素K、Ca、Na、Mg和微量元素Zn、Fe、Mn的含量均较高。

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为对比青海高原境内不同生境歧穗大黄中9种无机元素含量特征,用原子吸收光谱法分析了其宏量元素K、Na、Ca、Mg、P及微量元素Cu、Zn、Fe、Mn含量.结果表明,青海歧穗大黄植物与其土壤环境呈现出不同的无机元素含量特征,但一致表现为Ca和P在植物的富集,且植物中P含量随海拔升高而明显增加,Zn含量随海拔升高而增加.

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目的对比分析国家一类动物药塞隆骨和禁用传统中药材虎骨中的19种矿物质元素的含量.方法骨骼样品经灰化或消解处理后,采用原子吸收光谱法、氢化物原子荧光光谱法、催化极谱法等分析方法测定矿物质元素.结果两种动物骨骼中元素含量差异显著,塞隆骨11种元素高于虎骨,特别是Cu、Zn、Fe、Mn、Se等生命活动必需微量元素塞隆骨极为显著地高于虎骨,而组成骨骼的主要成分Ca、P则为虎骨高于塞隆骨.矿物质元素在头骨、脊梁骨和腿骨中分布非常不平衡,多数元素以头骨中分布最为丰富,而5种常量元素Ca,P,Na,Mg,K的含量为腿骨>头骨>脊梁骨.骨骼中主要成分Ca和P的存在形式主要为羟磷灰石Ca10(PO4)6(OH)2.结论塞隆骨骨骼中的矿物质元素与虎骨有可比性,必需微量元素塞隆骨明显优于虎骨.

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采用220FS原子吸收光谱仪测定了传统藏药牦牛骨中的K、Na、Ca、Mg、P、Cu、Zn、Fe、Mn、Ni、Pb、Cd等12种矿物质元素含量。结果显示,藏药牦牛骨中含有丰富的矿物质元素,对儿童和青少年骨骼的生长发育,中老年骨质疏松症预防有着极为重要的营养学和治疗意义,开发前景广阔。