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41.
根据中国营养学会推荐的热量标准,研制了中学生营养平衡米膳食最佳模式。按该模式,中学生每日应摄入的膳食品种及其数量如下:主食:营养平衡米,初中男生510~597g,女生468~510g;高中男生618~683g,女生532~575g;副食相同:青菜或水果500g或600g,鱼或肉100g或50g,蛋类40g,大豆制品30g,花生油12.5g,盐6g。调查结果表明,蛋白质、脂肪、碳水化合物,热量摄入量全部达标准要求。Q(蛋白质)∶Q(脂肪)∶Q(碳水化合物):高中男女生为16∶20∶64,初中男、女生分别为17∶20∶63。提示中学生营养平衡米膳食最佳模式使中学生达到营养平衡,建议推广食用。 相似文献
42.
We study the limit theorem related to the interface of the three-dimensional Ising model. Dobrushin proved that the interface does not fluctuate and becomes rigid for sufficiently large. We define the random fieldX
L
(t, s), 0t, s1, on the interface, and prove that XL(t, s) converges to the Brownian sheet as L for sufficiently large, whereL denotes the size of the system. This result does not mean that the interface itself converges to the Brownian sheet. 相似文献
43.
气相色谱仪检定结果的不确定度评定 总被引:2,自引:0,他引:2
气相色谱仪检定结果的不确定度主要来源于流速稳定性、柱箱温度稳定性、基线噪声、定量重复性和标准物质进样量的不确定度。以TCD检测器为例进行分析,对气相色谱仪检定结果的不确定度进行评定,相对扩展不确定度为5%。 相似文献
44.
Analytical procedures for quantification of peptides in pharmaceutical research by liquid chromatography–mass spectrometry 总被引:6,自引:0,他引:6
John H Walden M Schäfer S Genz S Forssmann WG 《Analytical and bioanalytical chemistry》2004,378(4):883-897
Peptide quantification by liquid chromatography–mass spectrometry (LC–MS) combines the high resolving power of reversed-phase (RP) chromatography with the excellent selectivity and sensitivity of mass spectrometric detection. On the basis of comprehensive practical experience in the analysis of small molecules, pharmaceutical research is developing technologies for analysis of a growing number of peptidic drug candidates. This article is a detailed review of procedures based on LC–MS techniques for quantitative determination of peptides. With the focus on pharmaceutical applications several technologies for sample preparation, various aspects of peptide chromatography, important characteristics of ESI–MS, selectivity of MS-detection modes, the large variability of internal standards, and modern instrumentation are discussed. The demand for reliable, robust, sensitive, and accurate methods is discussed using numerous examples from the literature, complemented by experiments and results from our laboratory. 相似文献
45.
叠加法是由内标法衍生而来的一种气相色谱定量方法。对于较复杂混合物的分析,当选择内标物困难时,用叠加法定量更为方便。本文在大量实验的基础上,提出了叠加法定量过程中应注意的一些问题。 相似文献
46.
F. J. Molina A. O. Vila C. Llcer M. J. Martos J. E. Figueruelo 《Journal of separation science》1991,14(9):590-592
Internal calibration in modified hydrodynamic chromatography has been realized by the approach of Prieve and Hoysan, i.e. the use of polystyrene monodisperse latexes to evaluate the equivalent capillary radius, R. The value obtained has been used to estimate the average sizes of a variety of liposome samples from egg yolk lecithin. 相似文献
47.
48.
We present a unified approach for linear and nonlinear sensitivity analysis for models of reaction kinetics that are stated in terms of systems of ordinary differential equations (ODEs). The approach is based on the reformulation of the ODE problem as a density transport problem described by a Fokker-Planck equation. The resulting multidimensional partial differential equation is herein solved by extending the TRAIL algorithm originally introduced by Horenko and Weiser in the context of molecular dynamics (J. Comp. Chem. 2003, 24, 1921) and discussed it in comparison with Monte Carlo techniques. The extended TRAIL approach is fully adaptive and easily allows to study the influence of nonlinear dynamical effects. We illustrate the scheme in application to an enzyme-substrate model problem for sensitivity analysis w.r.t. to initial concentrations and parameter values. 相似文献
49.
While operational qualification (OQ) is a well-established term within equipment qualification, users of equipment often become unsure when it comes to implementation. The biggest problem is how to select procedures and acceptance criteria. Should these be the vendor's specifications or should the users define their own limits, and, if so, how? Should all instruments of the same type have the same values or should these be optimized for each individual instrument? This article will provide an overall strategy and specific examples for HPLC on how to select procedures and acceptance limits that are based on efficient use of resources, on practicality and on the intended use of the equipment. 相似文献
50.