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41.
42.
The paper is devoted to the research of large deviation probabilities in the approximation by compound Poisson law. 相似文献
43.
Oriňák Andrej Arlinghaus Heinrich Frank Vering Guido Justinová Martina Oriňáková Renáta Turčániová L’udmila Halama Maroš 《平面色谱法杂志一现代薄层色谱法》2003,16(1):23-27
JPC – Journal of Planar Chromatography – Modern TLC - Two interfaces have been tested for coupling thin-layer chromatography (TLC) with time-of-flight secondary-ion mass spectrometry... 相似文献
44.
Solichová D Melichar B Klejna M Jurašková B Královská L Bláha V Zd'ánský P Zadák Z 《Talanta》2003,60(2-3):459-465
Twelve self-sustaining nonagenarians, 10 women and two men, aged 94+/-3 years, and eight institutionalised nonagenarians, eight women, aged 91+/-1 year as well as 11 control subjects, seven women and four men, aged 84+/-5 years entered the study. Urinary neopterin, an indicator of systemic immune activation, and serum thiobarbituric acid reactive substances (TBARS), a marker of lipoperoxidation, were determined initially, and collection of the blood and urine samples was repeated at 3-month interval. Neopterin was measured in the urine specimens by reversed-phase high performance liquid chromatography. A C(18) reversed-phase column 3.3x150 mm, 5 mum-diameter packing Separon SGX was used. Potassium phosphate buffer (15 mmol l(-1), pH 6.4) at flow rate of 0.8 ml min(-1) was used as mobile phase. After centrifugation (5 min, 1300xg) and diluting 100 mul of urine specimens with 1.0 ml of mobile phase containing 2 g of disodium-EDTA per litre, a 20 mul sample was injected on a column. Neopterin was identified by its native fluorescence (353 nm excitation, 438 nm emission). Creatinine was determined by Jaffé kinetic reaction after dilution of sample 1:50 (v/v). The concentration of neopterin in urine was expressed as neopterin/creatinine ratio (mumol mol(-1) creatinine). TBARS were determined spectrofluorometrically using LS-5 spectrofluorimeter (excitation wavelength 528 nm, emission wavelength 558 nm) after extraction with n-butanol treatment with thiobarbituric acid. The significance of differences between nonagenarians and control group was examined by ANOVA-Kruskal-Wallis tests, using statistical software NCSS 6.0.21 (Kaysville, UT, 1996). The decision on significance was based on P=0.05. Urinary neopterin was significantly higher in institutionalised compared to self-sustaining subjects and controls (625+/-565 vs. 203+/-63 mumol mol(-1) creatinine, and 198+/-128 mumol mol(-1) creatinine, respectively, P=0.006). The serum TBARS were higher in both groups of nonagenarians (3.23+/-1.16 mumol l(-1) and 2.69+/-0.39 vs. 2.12+/-0.83 mumol l(-1) for the self-sustaining, institutionalised and controls, respectively, P=0.023). We conclude that the fluorimetric determinations of urinary neopterin and serum TBARS can be useful for the monitoring health status in the elderly patients. 相似文献
45.
Wenping Deng Gang Xu Lei Wan Anwen Liu Bo Gao Junhe Du Shuiming Hu Yang Chen 《Acta Physico》2008,24(8):1329-1334
Apparatus integrating a Fourier transform-infrared (FT-IR) spectrometer and a mid-infrared difference frequency generation (DFG) laser spectrometer was built for the study of the matrix isolation spectrum in solid molecular hydrogen. A 3-cm-long molecular hydrogen crystal was grown in a liquid-helium Dewar, and its infrared absorption spectrum in the 1-5 μm region was recorded to test the system. The W0(0) (ν=0←0, J=6←0) line around 2410 cm−1 of solid hydrogen was investigated with the DFG laser spectroscopy. High-resolution matrix isolation spectrum of CO2 co-deposited with hydrogen on a BaF2 cold plate at liquid-helium temperature was studied. 相似文献
46.
Synthesis of 1,3-Bis(trialkylammonio)-2-propanol Dihalides Exhibiting Retardant Activity toward Rape
Merkis A. I. Novickiene L. L. Daukšas V. K. Šaltite Z. A. Miliuviene L. I. Gaveliene V. A. 《Russian Journal of Applied Chemistry》2003,76(1):160-161
1,3-Bis(trialkylammonio)-2-propanol dihalides were prepared, and their retardant activity was studied in relation to the chemical structure. 相似文献
47.
R. Strašek 《Acta Mathematica Hungarica》2003,101(1-2):63-68
We consider the class of Euclidean algebras associated to Minkowski light cones and called Lorentz algebras. We prove that in Lorentz algebras the estimate ∥P(a,b) ∥∞≥(√2-1) ∥a∥∞ ∥b∥∞ is valid for the spectral norm and is therefore independent of the dimension of the Lorentz algebra. 相似文献
48.
本文研究了H_2O_2氧化光泽精发光反应及乙醇的敏化作用,发现加入乙醇可使铅催化H_2O_2,氧化光泽精的发光强度有较大幅度的增强;铅量在3×10 ̄(-7)~8×10 ̄(-5)g/mL。范围内与发光强度成正比.方法检出限为0.10μg/mL;对含4μg/mLPb(Ⅱ)11次重复测定,其RSD为2.3%.对32种常见的阴阳离子进行了干扰实验,表明方法具有较好的选择性。本法应用于水样及沉积物标样中痕量铅的测定,结果良好。 相似文献
49.
50.
Miroslav Menšík 《Czechoslovak Journal of Physics》1998,48(4):469-475
A time solution of the excimer-ion pair system is presented here with a special attention to the time asymptote.
Presented at the Czech-Israeli-German Symposium “Dynamical Processes in Condensed Molecular Systems”, Prague, Czech Republic,
26–30 May 1997.
This work was supported by the grant No. C 1050601 of the Grant Agency of the Academy of Sciences of the Czech Republic. 相似文献