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961.
Impossible differential cryptanalysis is one of the conventional methods in the field of cryptanalysis of block ciphers. In this paper, a general model of an impossible differential attack is introduced. Then, according to this model, the concept of an ideal impossible differential attack is defined and it is proven that the time complexity of an ideal attack only depends on the number of involved round key bits in the attack. 相似文献
962.
Faramarz Yousefpour Seyed Mohsen Hoseyni Seyed Mojtaba Hoseyni Seyed Ali Hashemi Olia Kaveh Karimi 《核技术(英文版)》2017,28(8)
The Level-2 probabilistic safety assessment (PSA) of pressurized water reactors studies the possibility of creep rupture for major reactor coolant system components during the course of high pressure severe accident sequences.The present paper covers this technical issue and tries to quantify its associated phenomenological uncertainties for the development of Level-2 PSA.A framework is proposed for the formal quantification of uncertainties in the Level-2 PSA model of a PWR type nuclear power plant using an integrated deterministic and PSA approach.This is demonstrated for estimation of creep rupture failure probability in station blackout severe accident of a 2-loop PWR,which is the representative case for high pressure sequences.MELCOR 1.8.6 code is employed here as the deterministic tool for the assessment of physical phenomena in the course of accident.In addition,a MATLAB code is developed for quantification of the probabilistic part by treating the uncertainties through separation of aleatory and epistemic sources of uncertainty.The probability for steam generator tube creep rupture is estimated at 0.17. 相似文献
963.
Amira Mohamed Mohsen Marwa Hasanein Asfour Abeer A. A. Salama 《Drug development and industrial pharmacy》2017,43(12):2043-2054
The main objective of the present work was to formulate, characterize, and evaluate silymarin (SM)-loaded bilosomes, compared to conventional liposomes, aiming at increasing the hepatoprotective activity of the drug. SM-loaded bilosomes were prepared by thin film hydration technique employing soybean phosphatidyl choline (SPC) and different bile salts. After being subjected to different methods of characterization, SM-loaded bilosomes were investigated for their hepatoprotective activity, in CCl4 hepatointoxicated rat model. The developed SM dispersions exhibited an entrapment efficiency ranging from 21.80?±?2.01 to 84.54?±?2.51% and a particle size diameter in the nanometric dimensions (413?±?96.9 to 686.9?±?62.38?nm), with a negative zeta potential values (<–45?mV). In vitro release study revealed a lower cumulative amount of drug released from the developed formulae, compared to free drug. Ex vivo intestinal uptake study, performed using confocal laser scanning calorimetry, revealed the superiority of bilosomal uptake compared to that of liposomes. In vivo studies revealed an enhanced hepatoprotective effect of SM-loaded bilosomes/liposomes compared to free drug. These results were in good correlation with histopathological examination. These findings support the potential use of bilosomes for improving the hepatoprotective activity of SM via oral administration. 相似文献
964.
Double diffusion convection in a cavity with a hot square obstacle inside is simulated using the lattice Boltzmann method. The results are presented for the Rayleigh numbers 104,105 and 106, the Lewis ... 相似文献
965.
Flame‐retardant polyvinylchloride (FRPVC),typically used in cable insulation and jacketing construction for multi‐purpose reactor (MPR) at Atomic Energy Authority of Egypt, as well as carbon‐black FRPVC (CB‐FRPVC) and nonflame‐retardant PVC and CB‐PVC materials produced by Egyptian Electrical Cable Company (EECC), have been irradiated up to 160 KGy, at room temperature with a 60Co gamma source. Free‐volumes and thermal stability of irradiated and nonirradiated PVC samples have been examined using positron annihilation Lifetime Spectroscopy (PALS) and thermogravimetric analysis (TGA). In addition, the mechanical properties: tensile strength and elongation at break were examined. Considerable presence of flame‐retardant and carbon black additives in CB‐FRPVC sample led to both quenching and inhibition of Ps formation. The mechanical and thermal characterization showed that irradiation of PVC samples up to 80 KGy effectively induced cross‐linking to maxima. Higher doses then after results in degradation and thus a decrease in mechanical strength. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
966.
Yaghoub Mansourpanah Sayed Siavash Madaeni Mohsen Adeli Ahmad Rahimpour Arman Farhadian 《应用聚合物科学杂志》2009,112(5):2888-2895
Blends of polyethersulfone/polyimide (PES/PI) were prepared by dissolving in dimethylformamide/dioxane (DMF/DO) to manufacture nanofiltration membranes by using polyvinylpirrolidone (PVP) as a pore former. The membrane modification was carried out by adding ethylenediamine (EDA) to open the imide group ring of PI and by using polyethyleneglycol (PEG)‐triazine, as a new modifier material, that was produced in the laboratory. This modification involves the formation of a covalence ‐C‐N‐ bound between PEG‐triazine and amine groups (according to addition‐elimination reactions) at different temperatures. After functionalizing the membranes, diethanolamine (DA) was utilized as a hydrophilic modifier to change the membranes properties. SEM, AFM, FTIR‐ATR, EDS (X‐ray analysis) and contact angle tests were carried out to characterize modified membranes. The hydrophilicity of PES/PI membranes was improved by modification. An increase in pure water flux (up to 195 kg/m2 h) and a decline in NaCl rejection (from 25 to 16%) are largely influenced by diminishing the PES/PI ratio in L1‐L5 membranes (Category 1). In L6, L7, and L8 membranes (Category 2), by introducing PEG‐triazine into the membrane recipe, salt rejection increased from 75 to 80%. Addition of DA further enhances the salt rejection up to 93%. Fluxes were approximately similar for membranes in Category 2. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
967.
Mohsen Mahmoudysepehr Vahak K. Marghussian 《Journal of the American Ceramic Society》2009,92(7):1540-1546
Zirconolite (CaZrTi2 O7 ) is a mineral that has a high containment capacity for actinides and lanthanides and is considered to be a good candidate for the immobilization of radioactive wastes. The glass–ceramic technique seems to be a very suitable and convenient method to produce zirconolite crystals by precipitating them in a specific glass matrix. In this study, development of a new zirconolite-based glass–ceramic belonging to SiO2 –PbO–CaO–ZrO2 –TiO2 –(B2 O3 –K2 O) system was investigated. The presence of PbO, together with B2 O3 and K2 O, allowed the preparation of a X-ray diffraction (XRD) amorphous glass with a relatively high concentration of ZrO2 and TiO2 , which was successfully converted to a glass–ceramic containing 34 wt% of zirconolite after heating at 770°C for 4 h. Differential thermal analysis, XRD, scanning electron microscope, and energy dispersive X-ray spectroscopy were used to determine the crystallization conditions, identify the crystallized phases, determine their compositions and quantities and observe and analyze the microstructures. The zirconolite crystals showed a platelet morphology with a monoclinic structure characterized by a =1.246 nm, b =0.7193 nm, c =1.128 nm, and β=100.508°. 相似文献
968.
Zohrab Ahmadi Mohsen Ashjari Rahil Hosseini Jaefar Rahman Nia 《Journal of Inorganic and Organometallic Polymers and Materials》2009,19(3):322-327
Antibacterial ceramic consisting silver nanoparticles in TiO2 (rutile phase) particles were prepared via the chemical deposition route. Structure of synthesized ceramic was characterized
using different methods of spectroscopies including; X-ray diffraction (XRD), TEM, and scanning probe microscopy (SPM). The
results show that very fine silver particles were loaded on the titania dispersedly and also no crystalline change happened
in the TiO2 structure. In order to preparation of antibacterial composite, ceramic was compounded into polypropylene using a Hakke internal
mixer in optimized conditions. Morphology of composite was confirmed by AFM images. Finally, antibacterial activity of composite
was studied against Staphylococcus aureus. Results show that the bactericidal effect of this composite is significant and suggesting the composite to be promising
candidate for applications in fields. 相似文献
969.
Isolation and Characterization of Novel Microsatellite Markers in Pomegranate (Punica granatum L.) 总被引:1,自引:0,他引:1
Seyed Mostafa Pirseyedi Sahar Valizadehghan Mohsen Mardi Mohammad Reza Ghaffari Parvaneh Mahmoodi Mehdi Zahravi Mehrshad Zeinalabedini Seyed Mojtaba Khayam Nekoui 《International journal of molecular sciences》2010,11(5):2010-2016
Pomegranate (Punica granatum L.) has been cultivated from ancient times for its economic, ornamental and medicinal properties globally. Here, we report the isolation and characterization of 12 polymorphic microsatellite markers from a repeat-enriched genomic library of Punica granatum L. The genetic diversity of these loci was assessed in 60 genotypes of Punica granatum L. All loci were variable: the number of polymorphic alleles per locus ranged from two to five (average 2.9). The observed and expected heterozygosities ranged from 0.15 to 0.87 and 0.29 to 0.65, respectively. The polymorphic information content ranged from 0.26 to 0.61 (average: 0.43). To the best of our knowledge, this is the first time that polymorphic microsatellite markers have been reported for P. granatum L. These new markers should allow studies of the population structure and genetic diversity of pomegranate to be performed in the future. 相似文献
970.
Fatemeh Sadat HOSEINIAN Aliakbar ABDOLLAHZADE Saeed Soltani MOHAMADI Mohsen HASHEMZADEH 《中国有色金属学会会刊》2017,27(3):686-693
The artificial neural network (ANN) and hybrid of artificial neural network and genetic algorithm (GANN) were applied to predict the optimized conditions of column leaching of copper oxide ore with relations of input and output data. The leaching experiments were performed in three columns with the heights of 2, 4 and 6 m and in particle size of <25.4 and <50.8 mm. The effects of different operating parameters such as column height, particle size, acid flow rate and leaching time were studied to optimize the conditions to achieve the maximum recovery of copper using column leaching in pilot scale. It was found that the recovery increased with increasing the acid flow rate and leaching time and decreasing particle size and column height. The efficiency of GANN and ANN algorithms was compared with each other. The results showed that GANN is more efficient than ANN in predicting copper recovery. The proposed model can be used to predict the Cu recovery with a reasonable error. 相似文献