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排序方式: 共有256条查询结果,搜索用时 15 毫秒
31.
Diler Aslan Filiz Kuralay Tijen Tanyalcin Orcan Tanyalcin 《Accreditation and quality assurance》2000,5(2):54-57
The effect of haematocrit and β-carotene levels on the serum total bilirubin measurement in two analytical methods was studied as an example of the impact of practical analytical quality in medical decision making. The precision characteristics of the two methods were very similar. Based upon the significant difference in the correlation coefficient in a method comparison study before and after 20% trimming of the data, an interference effect study was performed. Haemoglobin (expressed as haematocrit) and β-carotene were the substances studied to explain the observed differences. The bilirubin test results from the Wako bilirubinometer were easily affected (n=19;X(S): 13.83±2.43;t=–6.17;P=0.000) and more elevated than in the Vitros dry chemistry systems (n=18;X(S): 12.72±2.21;t=–2.48;P=0.017), due to the presence of β-carotene (>200 μg/dl). 相似文献
32.
We describe a platform technology, called metal-assisted and microwave-assisted evaporative crystallization (MA-MAEC), based on the combined use of silver nanoparticles and microwave heating for selective and rapid crystallization of small molecules. In this regard, the crystallization of a model small molecule (glycine) was achieved in several seconds. Glycine crystals grown on silver nanostructures with and without microwave heating were found to be larger than those grown on blank glass slides. The MA-MAEC technique has the potential to selectively grow the desired polymorphs of small molecules "on-demand" in a fraction of the time as compared to the conventional evaporative crystallization. 相似文献
33.
Muhammed Yousufuddin Joseph M. Aslan Frederick M. MacDonnell 《Journal of chemical crystallography》2011,41(11):1763-1767
Abstract
The X-ray crystal structure of (C54 H42 B2 N12 Zn)*2(C H Cl3) is reported. The title compound is a chloroform-solvated neutral complex crystallizing in the Triclinic space group, P − 1, with two half complexes (each located on a crystallographic center of inversion) and two full chloroform molecules appearing in the asymmetric unit. The capping ligands are related by symmetry and together form, essentially, an octahedral coordination sphere. Strain is apparent in the complex as indicated by asymmetric bond distances and angles. Final statistical data: R = 4.60% with I > 2σ(I), a = 11.2912(8) ?, b = 14.7912(11) ?, c = 17.0047(13) ?, α = 72.3560(10)°, β = 89.8950(10)°, γ = 88.1010(10)°, Z = 2. 相似文献34.
D. Aslan F. Kuralay T. Tanyalsin M. Topraksu 《Accreditation and quality assurance》1999,4(9-10):431-433
Applicability of Hoffman's average of normals (AON) method was evaluated in quality control (QC) for twenty clinical chemistry assays (ALT, Alb, ALP, AMY, AST, T. Bil, inP, Glu, Ca, Cl, T. Chol, Creat, CK, K, LD, T. Prot., Na, TG, BUN, Uric. A.) performed routinely in the Hospital of Medical Faculty of 9 Eylül University. Consecutive Texas Instruments XL-Dacos patient data were accumulated over 10 days. According to the guidelines developed by Cembrowsky et. al. for the implementation of average of patients (AOP) (also known as AON) procedure, the patient population mean, *p, population standard deviation, Sp, the ratio of Sp/Sa (Sa, the analytical standard deviation), and the approximate number of patient results averaged. Np (with Ped=0.50) were determined from the nomogram constructed by Cembrowsky et. al., illustrating the relationship between Np, Sp/Sa, and the probability of detecting a 2Sa shift (Ped) when the probability of false rejection, Pfr, is 0.01. The control limits and the truncation limits were selected as *p±2Sp and *p±2.58×Sp√Np, respectively. The estimated values were assessed for the applicability of AOP procedures in the clinical laboratory. We conclude that the AOP procedure is a valuable tool for instrument monitoring as an adjunct to more costly standard QC procedures and is also an efficient, cost-effective and rapid way of collecting appropriate information on large number of patients. 相似文献
35.
The effects of the nature and amount of base, substrate structure, amount of added water and solvent on the condensation of carbonyl compounds with cyclopentadiene in the presence of secondary amines were investigated. Based on these studies, a new efficient and green synthesis of fulvenes was developed. 相似文献
36.
Inequalities for the gamma function 总被引:1,自引:1,他引:0
Necdet Batir 《Archiv der Mathematik》2008,91(6):554-563
Some inequalities for the gamma function are given. These results refine the classical Stirling approximation and its many
recent improvements.
Received: 2 May 2008, Revised: 2 September 2008 相似文献
37.
Recently, the authors of [Commun. Theor. Phys. 56 (2011) 397] made a number of useful observations on Exp-function method. In this study, we focus on another vital issue, namely, the misleading results of double Exp-function method. 相似文献
38.
Differential-difference equations are considered to be hybrid systems because the spatial variable n is discrete while the time t is usually kept continuous.Although a considerable amount of research has been carried out in the field of nonlinear differential-difference equations,the majority of the results deal with polynomial types.Limited research has been reported regarding such equations of rational type.In this paper we present an adaptation of the(G /G)-expansion method to solve nonlinear rational differential-difference equations.The procedure is demonstrated using two distinct equations.Our approach allows one to construct three types of exact traveling wave solutions(hyperbolic,trigonometric,and rational) by means of the simplified form of the auxiliary equation method with reduced parameters.Our analysis leads to analytic solutions in terms of topological solitons and singular periodic functions as well. 相似文献
39.
We demonstrate the influence of electrical current on the ability of surface plasmons to amplify fluorescence signatures. An applied direct current across Silver Island Films (SIFs) of low electrical resistance perturbs the fluorescence enhancement. For a given applied current, surface plasmons in just-continuous films are sparsely available for fluorophore dipole-coupling and hence the enhanced fluorescence is gated as a function of the applied current. For thicker, low resistance films, sufficient charge carriers are now present in the metal that metal-enhanced fluorescence (MEF) is perturbed to a lesser extent, induced surface plasmons readily formed on the surface by the close-proximity dipole. 相似文献
40.
İsmail Aslan 《Mathematical Methods in the Applied Sciences》2011,34(8):990-995
In this paper, we present an application of some known generalizations of the Exp‐function method to the fifth‐order Burgers and to the seventh‐order Korteweg de Vries equations for the first time. The two examples show that the Exp‐function method can be an effective alternative tool for explicitly constructing rational and multi‐wave solutions with arbitrary parameters to higher order nonlinear evolution equations. Being straightforward and concise, as pointed out previously, this procedure does not require the bilinear representation of the equation considered. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献