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51.
In this paper, the X-rays emitted from the Rhodotron-TT200 cavity have been studied in depth. We found that the Bremsstrahlung interaction is the only contribution of X-ray generation important to safety. The X-ray dose rate in the Rhodotron vault is calculated for normal conditions based on MCNP4C results. The presented calculation shows good agreement with the experimental measurements, which consequently confirms the reliability of the calculation for use in shielding design and other safety aspects. 相似文献
52.
Pouya Baniasadi Vladimir Ejov Jerzy A. Filar Michael Haythorpe Serguei Rossomakhine 《Mathematical Programming Computation》2014,6(1):55-75
We present a polynomial complexity, deterministic, heuristic for solving the Hamiltonian cycle problem (HCP) in an undirected graph of order $n$ . Although finding a Hamiltonian cycle is not theoretically guaranteed, we have observed that the heuristic is successful even in cases where such cycles are extremely rare, and it also performs very well on all HCP instances of large graphs listed on the TSPLIB web page. The heuristic owes its name to a visualisation of its iterations. All vertices of the graph are placed on a given circle in some order. The graph’s edges are classified as either snakes or ladders, with snakes forming arcs of the circle and ladders forming its chords. The heuristic strives to place exactly $n$ snakes on the circle, thereby forming a Hamiltonian cycle. The Snakes and Ladders Heuristic uses transformations inspired by $k$ -opt algorithms such as the, now classical, Lin–Kernighan heuristic to reorder the vertices on the circle in order to transform some ladders into snakes and vice versa. The use of a suitable stopping criterion ensures the heuristic terminates in polynomial time if no improvement is made in $n^3$ major iterations. 相似文献
53.
The role of folic acid in inducing of apoptosis by zinc(II) complex in ovary and cervix cancer cells
Yu Chuanrong Heidari Majd Mostafa Shiri Fereshteh Shahraki Somaye Karimi Pouya 《Molecular diversity》2022,26(3):1545-1555
Molecular Diversity - Herein, the synthesis, structure, binding affinity, cytotoxicity, and apoptotic properties of the new Zn(II) complex composed of folic acid and bipyridine ligands are... 相似文献
54.
Facile synthesis of tetrahydrobenzoxanthenones via a one‐pot three‐component reaction using an eco‐friendly and magnetized biopolymer chitosan‐based heterogeneous nanocatalyst
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A chitosan‐based magnetic nanocomposite was synthesized by an eco‐friendly and simple procedure, and was characterized using scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, X‐ray diffraction and Fourier transform infrared spectroscopy. It was then used for the efficient synthesis of tetrahydrobenzoxanthen‐11‐one derivatives via a one‐pot three‐component condensation of 2‐naphthol, various aldehydes and dimedone in ethanol. The catalyst was recovered easily and reused several times without significant loss of catalytic activity. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
55.
Barnoon Pouya Toghraie Davood Karimipour Arash 《Journal of Thermal Analysis and Calorimetry》2021,145(6):3301-3323
Journal of Thermal Analysis and Calorimetry - In this paper, the evaluation of the heat transfer rate and fluid flow in an enclosure with rotating circular obstacles has been studied. The enclosure... 相似文献
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Kargar H. Anaridokht F. Fallah-Mehrjardi M. 《Russian Journal of Organic Chemistry》2022,58(4):549-556
Russian Journal of Organic Chemistry - In the present study, a dioxomolybdenum(VI) complex chelated with the ONO tridentate Schiff base ligand supported on chloromethylated polystyrene [MoO2L@CMP]... 相似文献
58.
A novel porous metal–organic framework {Cu2(bbda)0.5(Hbbda)1.5(OAc)1.5.8H2O} (UoB-5) was synthesized under ultrasound irradiation by employing a new Schiff base ligand H2bbda (4,4′(1,4-phenylene bis (azanylylidene)) bis (methanylylidene))dibenzoic acid) and was fully characterized. The microporous nature of UoB-5 was confirmed by gas-sorption measurements. This framework acted as a highly effective heterogeneous catalyst for the alcohol oxidation reaction with tert-butyl hydroperoxide (t-BuOOH) as an oxidant. The presence of coordinatively unsaturated metal sites in UoB-5 could be the reason for high performance in this reaction. Furthermore, using the long linker with the free -NC group and uncoordinated -N atom on the wall of the pores created UoB-5 an excellent candidate for the catalytic activities without activation of the framework. It was confirmed with the heterogeneous catalytic experiments on the one-pot tandem synthesis of imines from benzyl alcohols and anilines. Eventually, the new Cu-MOF (UoB-5) could be an alternative catalyst as a more economically favorable and environmentally friendly in the catalysis field. 相似文献
59.
Kargar M Fayazmanesh K Alavi M Spyropoulos F Norton IT 《Journal of colloid and interface science》2012,366(1):209-215
In this study the potential ability of food-grade particles (at the droplet interface) to enhance the oxidative stability was investigated. Sunflower oil-in-water emulsions (20%), stabilised solely by food-grade particles (Microcrystalline cellulose (MCC) and modified starch (MS)), were produced under different processing conditions and their physicochemical properties were studied over time. Data on droplet size, surface charge, creaming index and oxidative stability were obtained. Increasing the food-grade particle concentration from 0.1% to 2.5% was found to decrease droplet size, enhance the physical stability of emulsions and reduce the lipid oxidation rate due to the formation of a thicker interfacial layer around the oil droplets. It was further shown that, MCC particles were able to reduce the lipid oxidation rate more effectively than MS particles. This was attributed to their ability to scavenge free radicals, through their negative charge, and form thicker interfacial layers around oil droplets due to the particles size differences. The present study demonstrates that the manipulation of emulsions' interfacial microstructure, based on the formation of a thick interface around the oil droplets by food-grade particles (Pickering emulsions), is an effective approach to slow down lipid oxidation. 相似文献
60.
Gwaram NS Ali HM Abdulla MA Buckle MJ Sukumaran SD Chung LY Othman R Alhadi AA Yehye WA Hadi AH Hassandarvish P Khaledi H Abdelwahab SI 《Molecules (Basel, Switzerland)》2012,17(3):2408-2427
Alzheimer's disease (AD) is the most common form of dementia among older people and the pathogenesis of this disease is associated with oxidative stress. Acetylcholinesterase inhibitors with antioxidant activities are considered potential treatments for AD. Some novel ketone derivatives of gallic hydrazide-derived Schiff bases were synthesized and examined for their antioxidant activities and in vitro and in silico acetyl cholinesterase inhibition. The compounds were characterized using spectroscopy and X-ray crystallography. The ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays revealed that all the compounds have strong antioxidant activities. N-(1-(5-bromo-2-hydroxyphenyl)-ethylidene)-3,4,5-trihydroxybenzohydrazide (2) was the most potent inhibitor of human acetyl cholinesterase, giving an inhibition rate of 77% at 100 μM. Molecular docking simulation of the ligand-enzyme complex suggested that the ligand may be positioned in the enzyme's active-site gorge, interacting with residues in the peripheral anionic subsite (PAS) and acyl binding pocket (ABP). The current work warrants further preclinical studies to assess the potential for these novel compounds for the treatment of AD. 相似文献