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排序方式: 共有197条查询结果,搜索用时 15 毫秒
81.
Baki B. Sadi Christopher Rinaldo Norman Spencer Chunsheng Li 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(1):179-189
A radiobioassay method has been developed for the sequential determination of 90Sr, 241Am and Pu isotopes in a urine sample. Unlike the existing methods using multiple extraction chromatographic cartridges, this work demonstrates an application of an automated ion chromatographic (IC) system for the separation of these radionuclides on a single IC column. The method meets the bioassay performance criteria for relative bias and relative precision as recommended by ANSI/HPS N13.30-2011. The detection limits for the radionuclides are found to be satisfactory for medical intervention in case of an accidental exposure scenario. Sample preparation time is less than 11 h. 相似文献
82.
Metal organic frameworks (MOFs) are a new class of nanoporous materials that have many potential advantages over traditional nanoporous materials for several chemical technologies including gas adsorption, catalysis, membrane-based gas separation, sensing, and biomedical devices. Knowledge on the interaction of guest molecules with the MOF surface is required to design and develop these MOF-based processes. In this review, we examine the importance of identification of gas adsorption sites in MOFs using the current state-of-the-art in experiments and computational modeling. This review provides guidelines to design new MOFs with useful surface properties that exhibit desired performances, such as high gas storage capacity, and high gas selectivity. 相似文献
83.
84.
85.
In this study, a numerical solution of the Regularized Long Wave (RLW) equation is obtained using Galerkin finite element method, based on two and three steps Adams Moulton method for the time integration and quadratic trigonometric B-spline functions for the space integration. After two different linearization techniques are applied, the proposed algorithms are tested on the problems of propagation of a solitary wave and interaction of two solitary waves. For the first test problem, the rate of convergence and the running time of the proposed algorithms are computed and the error norm $L_{\infty }$ is used to measure the differences between exact and numerical solutions. The three conservation quantities of the motion are calculated to determine the conservation properties of the proposed algorithms for both of the test problems. 相似文献
86.
Melahat Göktaş Mehmet Nuri Atalar Ahmet T. Tekeş Baki Hazer 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(11):854-863
One-step synthesis of the triblock copolymers was carried out by reversible addition–fragmentation chain transfer (RAFT) polymerization of methyl methacrylate (MMA) and ring-opening polymerization (ROP) of β-butyrolactone (BL) or ?-caprolactone (CL) using a novel difunctional macro-RAFT agent. For this purpose, primarily PEG-Br (polyethylene glycol bromine) was obtained by using 3-bromopropanoyl chloride and PEGs (polyethylene glycols) with different molecular weights. Then, macro-RAFT agent was synthesized by the reaction of potassium ethyl xanthogenate and PEG-Br. By using macro-RAFT agent, poly(MMA-b-EG-b-BL), and poly(MMA-b-EG-b-CL) triblock copolymers were synthesized by changing some polymerization conditions such as monomer/initiator concentration, polymerization time. The effect of the reaction conditions on the polydispersity and molecular weights were also investigated. The block lengths of the triblock copolymers were calculated by using 1H-nuclear magnetic resonance (1H-NMR) spectra. It was observed that the block length could be altered by varying the monomer and initiator concentrations. The characterization of the products were achieved using 1H-NMR, Fourier-transform infrared spectroscopy (FTIR), gel-permeation chromatography (GPC), thermogravimetric analysis (TGA), and fractional precipitation (γ) techniques. 相似文献
87.
Mathematical Notes - In this paper, we deal with the equation $$(a^{n}-2)(b^{n}-2)=x^{2}$$ , $$2\leq a3$$ is odd and $$P_{k},Q_{k}$$ are the Pell and Pell Lucas numbers, respectively. We also... 相似文献
88.
Keskin Refik Karaatlı Olcay Şiar Zafer Öğüt Ümmügülsüm 《Periodica Mathematica Hungarica》2017,75(2):336-344
Periodica Mathematica Hungarica - In this paper, we consider the simultaneous Pell equations 0.1 $$\begin{aligned} x^{2}-(a^{2}-1)y^{2}= & {} 1, \nonumber \\ y^{2}-pz^{2}= & {} 1,... 相似文献
89.
In this paper we obtain some new identities containing Fibonacci and Lucas numbers. These identities allow us to give some
congruences concerning Fibonacci and Lucas numbers such as L
2mn+k
≡ (−1)(m+1)n
L
k
(mod L
m
), F
2mn+k
≡ (−1)(m+1)n
F
k
(mod L
m
), L
2mn+k
≡ (−1)
mn
L
k
(mod F
m
) and F
2mn+k
≡ (−1)
mn
F
k
(mod F
m
). By the achieved identities, divisibility properties of Fibonacci and Lucas numbers are given. Then it is proved that there
is no Lucas number L
n
such that L
n
= L
2
k
t
L
m
x
2 for m > 1 and k ≥ 1. Moreover it is proved that L
n
= L
m
L
r
is impossible if m and r are positive integers greater than 1. Also, a conjecture concerning with the subject is given. 相似文献
90.
Bilge Taner Pervin Deveci Zafer Üstündaǧ Selda Keskin Emine Özcan Ali Osman Solak 《Surface and interface analysis : SIA》2012,44(2):185-191
3‐Aminophenylcalix[4]pyrrole (3APCP) was grafted to a glassy carbon (GC) surface during the electrochemical oxidation process in 0.1 M tetrabutylammoniumtetra‐fluoroborate (TBATFB) containing acetonitrile solution. The presence of a surface film was confirmed electrochemically by comparing voltammograms of dopamine and ferricyanide redox probes at the bare and modified electrodes. Reflection‐absorption infrared spectroscopy (RAIRS), XPS, atomic force microscopy (AFM), ellipsometry and the contact angle measurements were also employed to characterize 3APCP film on GC electrode. RAIRS analysis revealed that calix[4]pyrrole was bonded to the glassy carbon surface via the etheric linkage. The stability of the modified GC electrode was also studied. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献