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Journal of Thermal Analysis and Calorimetry - This article considers viscoelastic effects on the enhancement of transportation of heat in thin-film flow when the relaxation time phenomenon is... 相似文献
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Santa Islam Syed Shaheen Shah Prof. Shamsun Naher Dr. Muhammad Ali Ehsan Dr. Md. Abdul Aziz Dr. A. J. Saleh Ahammad 《化学:亚洲杂志》2021,16(22):3516-3543
Dopamine (DA) is an important neurotransmitter, which is created and released from the central nervous system. It plays a crucial role in human activities, like cognition, emotions, and response to anything. Maladjustment of DA in human blood serum results in different neural diseases, like Parkinson's and Schizophrenia. Consequently, researchers have started working on DA detection in blood serum, which is undoubtedly a hot research area. Electrochemical sensing techniques are more promising to detect DA in real samples. However, utilizing conventional electrodes for selective determination of DA encounters numerous problems due to the coexistence of other materials, such as uric acid and ascorbic acid, which have an oxidation potential close to DA. To overcome such problems, researchers have put their focus on the modification of bare electrodes. The aim of this review is to present recent advances in modifications of most used bare electrodes with carbonaceous materials, especially graphene, its derivatives, and carbon nanotubes, for electrochemical detection of DA. A brief discussion about the mechanistic phenomena at the electrode interface has also been included in this review. 相似文献
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The central idea of this paper is to construct a new mechanism for the solution of Abel’s type singular integral equations that is to say the two-step Laplace decomposition algorithm. The two-step Laplace decomposition algorithm (TSLDA) is an innovative adjustment in the Laplace decomposition algorithm (LDA) and makes the calculation much simpler. In this piece of writing, we merge the Laplace transform and decomposition method and present a novel move toward solving Abel’s singular integral equations. 相似文献
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Shahid Muhammad Kim Kwangsoo Kim Guinyun Naik Haladhara Zaman Muhammad Lee Young-Ouk Cho Young-Sik 《Journal of Radioanalytical and Nuclear Chemistry》2017,311(3):1971-1981
Journal of Radioanalytical and Nuclear Chemistry - We measured excitation functions for the production of the 108m,108g,109g,110m,110g,111gIn, the 109g,111mCd, and the 105g,106m,110m,111gAg in... 相似文献
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ABSTRACT: BACKGROUND: Pyrethroids are widely used for the control of pests and insects, as pyrethroids are believed to pose very little risk to human health and environment. However, exposure to the pyrethroids exceeding the label directions might adversely affect human health and environment. Hence a careful selection of environment friendly household product is required that must contain exactly the label claimed pyrethroids amount. RESULTS: A sensitive and robust TLC-densitometric method for simultaneous quantification of commonly used synthetic pyrethroids including esbiothrin, alpha-cypermethrin and cis/trans permethrin in agricultural and domestic products has been developed and validated. TLC aluminum plates, precoated with 0.2 mm thick layer of silica gel 60 F-254, were used for chromatographic process. Densitometric analysis of chromatoplates was carried out in absorbance mode at corresponding lamdamax of each pyrethroid. Equally valid common mobile phase for all pyrethroids consisted of hexane-dichloromethane-ethylacetate-formic acid (8:1.5:0.4:0.1 v/v/v/v) which provided sharp and symmetrical peaks of esbiothrin, alpha-cypermethrin, trans-permethrin and cis-permethrin, at Rf 0.31, 0.53, 0.6 and 0.65, respectively. Linear regression data for respective calibration curves showed a good linearity for all pyrethroids with r = 0.991-0.996. Limits of detection (LOD) and limits of quantification (LOQ) for all pyrethroids were found in the range of 1.6-2.8 and 4.9-8.5 ng/spot, respectively. CONCLUSIONS: The developed method is applicable for separating the mixture of pyrethroids and at the same time, it is also valid for separating their isomers. The method is reproducible, precise and accurate for the quantitative determination of pyrethroids in agricultural and domestic products. 相似文献
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New metal based triazoles (1–12) have been synthesized by the interaction of novel Schiff base ligands (L1–L3) with the Co(II), Ni(II), Cu(II) and Zn(II) metal ions. The Schiff base ligands and their all metal(II) complexes have been thoroughly characterized using various physical, analytical and spectroscopic techniques. In vitro bacterial and fungal inhibition studies were carried out to examine the antibacterial and antifungal profile of the Schiff bases in comparison to their metal(II) complexes against two Gram‐positive, four Gram‐negative and six fungal strains. The bioactivity data showed the metal(II) complexes to have more potent antibacterial and antifungal activity than their uncomplexed parent Schiff bases against one or more bacterial and fungal species. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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