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71.
Peng Yeping Zahedidastjerdi Ali Abdollahi Ali Amindoust Atefeh Bahrami Mehrdad Karimipour Arash Goodarzi Marjan 《Journal of Thermal Analysis and Calorimetry》2020,139(4):2623-2631
Journal of Thermal Analysis and Calorimetry - This work is a three-dimensional numerical study of a U-shaped evacuated tube solar collector employing different types of oxide nanofluids including... 相似文献
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Reza Hoseinpour Kouhestany Atefeh Tamaddon Homayoon Ahmad Panahi Arash Afshar Ebrahimi Rahebeh Amiri 《Biomedical chromatography : BMC》2022,36(3):e5284
Polyaniline nanofiber films were fabricated on the surface of stainless steel wire via a controllable and simple electrophoretic deposition route from a nonaqueous colloidal suspension consisting of polyaniline nanofibers. The prepared coating material was then characterized by field emission scanning electron microscopy equipped with energy dispersive spectroscopy and elemental mapping analysis. The fabricated polyaniline film-coated stainless steel wire was then utilized as an effective and novel sorbent phase for solid-phase microextraction of tamoxifen for subsequent gas chromatography/flame ionization detection of this anticancer drug. Parameters consisting of the temperature, extraction time, salt concentration, agitation speed, pH, temperature and time of desorption were studied and optimized using a one-at-a-time strategy. Under the optimum conditions, detection limit (S/N = 3), the limit of quantification (10/3 limit of detection), linear dynamic range, repeatability and reproducibility values of 0.51 μg L−1, 1.7 μg L−1, 2–1,130 μg L−1, 5.7% and 8.6% were attained, respectively. The prepared fiber can preserve 90% of its efficacy after 20 consecutive cycles, demonstrating the suitable thermal stability and cyclability of the proposed solid-phase microextraction coating material for the determination of tamoxifen by gas chromatography/flame ionization detection. The route was effectively utilized to determine tamoxifen in urine samples, with relative recoveries ranging from 89 to 106%. 相似文献
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Guido M. Kukuk Dariusch R. Hadizadeh Jürgen Gieseke Marcus von Falkenhausen Ingrid B?hm Renate Semrau Horst Urbach Arne Koscielny Frauke Verrel Kai Wilhelm Hans H. Schild Winfried A. Willinek 《Magnetic resonance imaging》2010,28(9):1311-1318
PurposeTo present the feasibility of highly undersampled contrast-enhanced MRA (CE-MRA) of the supraaortic arteries with a 16-channel neurovascular coil at 3.0 T using parallel imaging in two directions with parallel imaging factors (PIF) up to 16.Materials and MethodsInstitutional review board approval and informed consent were obtained. In a prospective study, MRA protocols including PIF of 1, 2, 4, 9 and 16 yielding a spatial resolution from 0.81×0.81×1.0 mm3 to 0.46×.46×0.98 mm3 were acquired. In 32 examinations, image quality and vascular segments were rated independently by two radiologists. SNR estimations were performed for all MRA protocols.ResultsThe use of high PIF allowed to shorten acquisition time from 2:09 min down to 1:13 min and to increase the anatomic coverage while maintaining or even increasing spatial resolution down to 0.46×0.46×0.98 mm3. The larger anatomic coverage that was achieved with the use of high PIF allowed for visualization of vascular structures that were not covered by the standard protocols. Despite the resulting lower SNR using high PIF, image quality was constantly rated to be adequate for diagnosis or better in all cases.ConclusionThe use of high PIF yielded diagnostic image quality and allowed to increase the anatomic coverage while maintaining or even improving spatial resolution and shortening the acquisition time. 相似文献
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We investigate unconditional security for message authentication protocols that are designed using two-channel cryptography. (Two-channel cryptography employs a broadband, insecure wireless channel and an authenticated, narrow-band manual channel at the same time.) We study both noninteractive message authentication protocols (NIMAPs) and interactive message authentication protocols (IMAPs) in this setting. First, we provide a new proof of nonexistence of nontrivial unconditionally secure NIMAPs. This proof consists of a combinatorial counting argument and is much shorter than the previous proof by Wang and Safavi-Naini, which was based on probability distribution arguments. We also prove a new result which holds in a weakened attack model. Further, we propose a generalization of an unconditionally secure 3-round IMAP due to Naor, Segev and Smith. The IMAP is based on two ?-Δ universal hash families. With a careful choice of parameters, our scheme improves that of Naor et al. Our scheme is very close to optimal for most parameter situations of practical interest. Finally, a variation of the 3-round IMAP is presented, in which only one hash family is required. 相似文献
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Tricyclic dihydropyridines like ZM244085 are potential KATP channel openers. In this study 3‐cyanophenyl ring of ZM244085 was replaced with imidazolyl ring. So, 9‐[1‐benzyl‐5‐(alkylsulfonyl)‐1H‐2‐imidazolyl]perhydro‐1,8‐acridinediones ( 5d‐f ) were synthesized from 2‐alkylsulfonyl‐1‐benzyl‐5‐formylimidazole ( 4d‐f ) and cyclohexane‐1,3‐dione according to classical Hantzch synthesis as potential potassium channel modulators. 相似文献
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This paper provides with a generalization of the work by Chelyshkov (Electron. Trans. Numer. Anal. 25(7): 17–26, 2006), who has introduced sequences of orthogonal polynomials over [0,1] which can be expressed in terms of Jacobi polynomials.
We develop a new approach of product integration algorithm based on these orthogonal polynomials including the numerical quadratures
for solving the nonlinear weakly singular Volterra integral equations. The convergence analysis of the proposed scheme is
derived and numerical results are given showing a marked improvement in comparison with recent numerical methods. 相似文献
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Majid Soleimani Majid Ghahraman Afshar Atefeh Shafaat Gastón A. Crespo 《Electroanalysis》2013,25(5):1159-1168
We report here a novel carbon paste electrode (CPE) which is able to quantitatively sense tramadol under physiological conditions without sample preparation step. The selectivity of CPE is modified by applying molecularly imprinted polymer (MIP) technology. Multiwalled carbon nanotubes (MWCNTs) are incorporated in the structure of CPE to improve the conductivity and the ion‐to‐electron transduction. The electrode shows a wide dynamic linear range for tramadol from 10?7 to 10?3 M. The observed limit of detection and % RSD are 5×10?7 M and 1.8 %, respectively. Finally, the proposed method is applied to determine tramadol in urine and medicinal tablets. 相似文献
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T. Frederico Lauro Tomio A. Delfino M. R. Hadizadeh M. T. Yamashita 《Few-Body Systems》2011,51(2-4):87-112
The role of scales in the physics of large few-body systems is reviewed. They are evidenced by considering weakly-bound three and four particles, where point-like interactions are regularized and renormalized in a procedure characterized by the emergence of physical scales fixed by observables. The results obtained with renormalized zero-ranged two-body interactions are presented in the form of universal scaling plots, or correlations between observables, where we also consider results of several other model calculations, as well as experimental results obtained in nuclear physics and cold-atom laboratories. The universal correlations between few-body observables are useful to predict one in terms of another observable and we discuss applications in setting low energies properties of halo nuclei, molecular and cold atom systems. 相似文献
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