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排序方式: 共有314条查询结果,搜索用时 15 毫秒
101.
Şenol Zeynep Mine Şenol Arslan Dilek Şimşek Selçuk 《Journal of Radioanalytical and Nuclear Chemistry》2019,319(3):791-803
Journal of Radioanalytical and Nuclear Chemistry - The thiol-functional hydrotalcite (Mg/Al-LDO-SH) composite materials were prepared and characterized by EDS, SEM, FT-IR and XRD. The variables... 相似文献
102.
Cihan 《数学物理学报(B辑英文版)》2002,22(3)
In this paper the authors investigate hypersurfaces M of a semi-Euclidean space Esn+1, n ≥ 4, satisfying (aC +βR). H = LkQ(g, Hk), k = 1,2,3. Using obtained results they show additional curvature properties of investigated hypersurfaces. 相似文献
103.
Arslan I Walmsley JC Rytter E Bergene E Midgley PA 《Journal of the American Chemical Society》2008,130(17):5716-5719
Cobalt-based Fischer-Tropsch systems are widely used to convert synthesis gas to clean hydrocarbon fuel. However, surprisingly little is known about the morphology of the catalysts on the nanoscale. Here we show that scanning transmission electron tomography reveals their true 3-D morphology and provides direct evidence that the support controls the final morphology of the catalyst. Such direct local three-dimensional measurements provide unprecedented insight into catalysis, and can henceforth transform our understanding of these complex materials. 相似文献
104.
Choonkil Park Arslan Hojt Ansari Muaadh Almahalebi 《Journal of Fixed Point Theory and Applications》2017,19(4):2417-2425
In this paper, we introduce an \(m{\text{th}}\) root functional equation. Using the fixed point approach, we prove the Hyers–Ulam stability of the \(m{\text{th}}\) root functional equation in \(C^{*}\)-algebras. 相似文献
105.
Arslan M Masnovi J Krafcik R 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2007,66(4-5):1063-1067
Dimer model compounds of polyvinylcarbazoles (1,n-di(N-carbazolyl)alkanes, when n=1-5) were synthesized to model the effects of distance and orientation between carbazole groups in polymeric systems. Charge-transfer (CT) complexes of carbazole, N-ethylcarbazole and 1,n-di(N-carbazolyl)alkanes with p-chloranil (p-CHL) have been investigated spectrophotometrically in dichloromethane. The colored products are measured spectrophotometrically at different wavelength depending on the electronic transition between donors and acceptor. The formation constants of the CT complexes were determined by the Benesi-Hildebrand equation. The thermodynamic parameters were calculated by Van't Hoff equation. Stochiometries of the complexes formed between donors and acceptor were defined by the Job's method of the continuous variation and found in 1:1 complexation with donor and acceptor at the maximum absorption bands. 相似文献
106.
In this article we investigate Vranceanu rotation surfaces with pointwise 1- type Gauss map in Euclidean 4-space $
\mathbb{E}^4
$
\mathbb{E}^4
. We show that a Vranceanu rotation surface M has harmonic Gauss map if and only if M is a part of a plane. Further, we give necessary and sufficent conditions for Vranceanu rotation surface to have pointwise
1-type Gauss map. 相似文献
107.
Yasin Arslan Emrah YildirimMehrdad Gholami Sezgin Bakirdere 《Trends in analytical chemistry : TRAC》2011,30(4):569-585
Speciation studies are much more important than total element determination because toxicity of many elements depends on their chemical forms. Nobody can claim that a foodstuff is very dangerous to eat by determining total arsenic due to the possibility that the arsenic could be present in non-toxic forms. Hence, speciation studies are crucial in any matrix relevant to human beings.Trace-element speciation requires sufficiently sensitive procedures to monitor each species at trace levels. One way to increase the sensitivity for elements forming volatile species is coupling high-performance liquid chromatography (HPLC) with chemical-vapor generation (CVG). This review aims to highlight not only development of HPLC-CVG techniques for ultratrace-elemental speciation in a variety of matrices but also their application. In addition, we discuss the advantages and the disadvantages of these techniques. 相似文献
108.
The paper proves the convergence of (Approximate) Iterated Successive Approximations Algorithm for solving infinite-horizon sequential decision processes satisfying the monotone contraction assumption. At every stage of this algorithm, the value function at hand is used as a terminal reward to determine an (approximately) optimal policy for the one-period problem. This policy is then iterated for a (finite or infinite) number of times and the resulting return function is used as the starting value function for the next stage of the scheme. This method generalizes the standard successive approximations, policy iteration and Denardo’s generalization of the latter. 相似文献
109.
Sezgin Bakırdere Selin Bora E. Gülhan Bakırdere Fırat Aydın Yasin Arslan O. Tarık Komesli Işıl Aydın Emrah Yıldırım 《Central European Journal of Chemistry》2012,10(3):675-685
Carcinogenic and mutagenic properties of aflatoxin species are known in literature. Their intake over a long time period might
be health-dangerous for human even at trace levels. It is well known that different foodstuffs can be contaminated by aflatoxin
species through growing and storage. Due to the serious health effects, sensitive determination of aflatoxin species in any
matrices related with the human being is very crucial at trace levels. In literature, there are sensitive techniques to analyze
the different samples for the contents of their aflatoxin species. Each technique has some advantages and disadvantages over
the other techniques. This review aims to summarize the different health effects of aflatoxin species, development of analytical
techniques and applications of developed techniques in a variety of matrices.
相似文献
110.
The possible stable forms of 3-phenylpropylamine (3-PPA) molecule were experimentally and theoretically studied by infrared and Raman spectroscopy. FT-IR and Raman spectra of 3-PPA were recorded in the regions of 4000–400 cm−1 and 3700–60 cm−1, respectively. The potential energy surface corresponding to the internal rotations of the molecule was investigated by semi-empirical quantum mechanical methods, and appropriate conformers defined with B3LYP hybrid density functional theory method along with the basis sets of different size and type. Results from experimental and theoretical data showed the trans–trans–gauche (TTG) to be the most stable form of a 3-PPA molecule. 相似文献