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91.
Abasalt Hosseinzadeh Colagar Hamed Memariani Farshad Sohbatzadeh Azadeh Valinataj Omran 《Applied biochemistry and biotechnology》2013,171(7):1617-1629
Nonthermal atmospheric plasma jet, a promising technology based on ionized gas at low temperatures, can be applied for disinfection of contaminated surfaces. In this study, Escherichia coli cells and their macromolecules were exposed to the nonthermal atmospheric argon plasma jet for different time durations. Total protein, genomic DNA, and malondialdehyde (MDA) levels of E. coli were assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and silver staining; agarose gel electrophoresis; and measurement of absorbance at 534 nm, respectively. After exposure, the spectroscopic results of liquid samples indicated that the survival reduction of E. coli can reach to 100 % in an exposure time of 600 s. Moreover, inactivation zones of E. coli, DNA degradation, and MDA levels were significantly increased. Additionally, banding patterns of total protein were changed and amino acid concentrations increased following ninhydrin test. The experimental results suggest that the nonthermal plasma could serve as an effective instrument for both sterilizing E. coli and degrading macromolecules from the surface of the objects being sterilized. 相似文献
92.
Reza Maddahian Azadeh Kebriaee Bijan Farhanieh Bahar Firoozabadi 《Archive of Applied Mechanics (Ingenieur Archiv)》2011,81(4):489-501
In this research, the developing turbulent swirling flow in the entrance region of a pipe is investigated analytically by
using the boundary layer integral method. The governing equations are integrated through the boundary layer and obtained differential
equations are solved with forth-order Adams predictor-corrector method. The general tangential velocity is applied at the
inlet region to consider both free and forced vortex velocity profiles. The comparison between present model and available
experimental data demonstrates the capability of the model in predicting boundary layer parameters (e.g. boundary layer growth,
shear rate and swirl intensity decay rate). Analytical results showed that the free vortex velocity profile can better predict
the boundary layer parameters in the entrance region than in the forced one. Also, effects of pressure gradient inside the
boundary layer is investigated and showed that if pressure gradient is ignored inside the boundary layer, results deviate
greatly from the experimental data. 相似文献
93.
Kheyrollah Mehrani Azadeh Mehrani Mostafa M. Amini Omid Sadeghi Najmeh Tavassoli 《Mikrochimica acta》2011,173(3-4):521-527
Nanoporous silicas of the type SBA-15 (Santa Barbara Amorphous) and MCM-48 (Mobile Composition of Material) were modified with dipyridylamine (dipy) and used as solid phases for the extraction of Pd(II) ions. The experimental conditions (pH, sample and eluent flow rates, type and quantity of eluent) were optimized. The recovery values were ~ 99.7 and ~ 93.4% for dipy-MCM-48 and dipy-SBA-15, respectively, the limits of detection were <0.08 and <0.11 ng L?1, the pre-concentration factors were 725 and 550, and the adsorption capacity was >78 mg g?1. The procedure was applied to the preconcentration of Pd(II) in real samples. Figure
Nanoporous silicas of the type SBA-15 and MCM-48 were modified with dipyridylamine and used as solid-phase for the extraction of Pd(II) ions. The experimental conditions were optimized and the recovery values were determined. The procedure was applied to the pre-concentration of Pd(II) in real samples. 相似文献
94.
One of the most important results of Chevalley's extension theorem states that every valuation domain has at least one extension to every extension field of its quotient field. We state a generalization of this result for Prüfer domains with any finite number of maximal ideals. Then we investigate extensions of semilocal Prüfer domains in algebraic field extensions. In particular, we find an upper bound for the cardinality of extensions of a semilocal Prüfer domain. Moreover, we show that any two extensions of a semilocal Prüfer domain are incomparable (by inclusion) in an algebraic extension of fields. 相似文献
95.
Crystallography Reports - A new co-crystal compound of 4,4'-bipyridine and phenylsuccinic acid was synthesized and characterized by elemental analysis, infrared and ultraviolet–visible... 相似文献
96.
Nemati Azadeh Sayyahi Soheil Zare-Shahabadi Vahid Anaraki-Ardakani Hossein 《Research on Chemical Intermediates》2020,46(7):3397-3411
Research on Chemical Intermediates - In this study, we examined the catalytic role of low rhodium embedded onto MOF-5 as a hard template, in the ring opening reaction of epoxides with N3?... 相似文献
97.
Highly ordered mesoporous molecular sieves AlMCM‐41 and a new NiO/AlMCM‐41 nanocomposite were synthesized using a sol–gel method. Fourier transform infrared (FT‐IR) spectroscopy, X‐ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X‐ray spectroscopy (EDX), and N2 adsorption desorption analyses were used to examine the structure, morphology, size and phase composition of the synthesized NiO/AlMCM‐41 nanocomposites. AlMCM‐41 embedded with NiO nanoparticles was subsequently prepared using different nickel loadings in a direct synthetic route. The results show the successful deposition of NiO nanoparticles onto the framework of AlMCM‐41. AlMCM‐41 provides enormous benefits such as environmentally safe, economic viability and porosity when used as support for NiO nanoparticles. The excellent catalytic activities of AlMCM‐41 and NiO/AlMCM‐41 were investigated for the reduction of nitrophenols (4‐NP, 2‐NP) to aminophenols (4‐AP, 2‐AP) in water at ambient temperature. The best observed performance of reduction of NP with 100% conversion into analogous amino derivatives occurred within 6 min with an estimated rate constant of 0.46 min?1. The efficiency of reduction was observed to increase as a function of NiO enrichment. The NiO/AlMCM‐41 nanocomposite could be recycled and reused up to five times without noticeable change in its structure and activity. These properties make NiO/AlMCM‐41 nanocomposite an ideal platform to study various heterogeneous catalytic processes which can have application in purification, catalysis, sensing devices, and green chemistry. 相似文献
98.
Saadati-Eskandari Naghmeh Navidpour Latifeh Yaghmaei Parichehreh Ebrahim-Habibi Azadeh 《Applied biochemistry and biotechnology》2019,189(1):305-317
Applied Biochemistry and Biotechnology - The effect of 16 amino acids (AA) with various physicochemical properties was investigated on human lysozyme (HL) heat-induced amorphous aggregation.... 相似文献
99.
Amir Reza Abbasi Nourolah Noori Azadeh Azadbakht Mohsen Bafarani 《Journal of the Iranian Chemical Society》2016,13(7):1273-1281
The growth of Cu2O nanoparticles on silk fibers was achieved under ultrasound irradiation. The effect of temperature, reaction time, ultrasound irradiation and solvent in growth of the Cu2O nanoparticles upon fiber has been studied. These systems depicted a decrease in the size accompanying a decrease in the reaction time. Particle sizes and morphology of nanoparticle depend on power of ultrasound irradiation. Results show that in presence of ultrasound radiation, particle sizes are in a very low range. The susceptibility of the microorganisms to Cu2O upon fiber was determined by minimum inhibitory concentration (MIC) using micro dilution method and disk diffusion method. Results suggest that the Cu2O nanoparticles on silk fibers have antibacterial activity. The Cu2O nanoparticles upon fibers were characterized with X-ray powder diffraction (XRPD) and scanning electron microscopy (SEM). XRPD analyses indicated that the prepared Cu2O nanoparticles on silk fibers were crystalline. 相似文献
100.
Hajizadeh Alireza Bahramian Ahmad Reza Seifi Azadeh Naseri Iman 《Journal of Sol-Gel Science and Technology》2015,74(1):220-226
Journal of Sol-Gel Science and Technology - New carbon aerogels were prepared using Novolac sol as precursor. The elaboration process and the structural characterizations of these porous carbon... 相似文献