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排序方式: 共有244条查询结果,搜索用时 62 毫秒
21.
S. Shahidi A. Rashidi M. Ghoranneviss A. Anvari M. K. Rahimi M. Bameni Moghaddam J. Wiener 《Cellulose (London, England)》2010,17(3):627-634
In this work, the silver particle absorption and antibacterial activity of cotton fabric when modified by low temperature
plasma were investigated. The modification consisted of plasma pre-functionalization followed by one-step wet treatment with
silver nitrate solution. Oxygen and nitrogen were used as the working gases in the system, and the results were compared.
The results showed that nitrogen plasma-treated samples can absorb more silver particles than oxygen-treated samples, and
thus the antibacterial activity of the samples in this case, which was analyzed by the counting bacteria test, was increased
considerably. 相似文献
22.
We demonstrate line-by-line pulse shaping of optical comb lines separated by 6.25 GHz. An array of injection-locked VCSELs independently modulate four optical comb lines at frequencies up to 3.125 GHz, updating the pulse shape on the time scale of the pulse period. 相似文献
23.
Zohreh Rashidi RanjbarAli Morsali 《Polyhedron》2011,30(6):929-934
A nano-sized mixed-ligand Cd(II) coordination polymer, {[Cd(bpa)(4,4′-bipy)2(H2O)2](ClO4)2}n (1); bpa = trans-1,2-bis(4-pyridyl)ethane and 4,4′-bipy = 4,4′-bipyridine, has been synthesized by a sonochemical method and characterized by IR and 1H NMR spectroscopy. Compound 1 grows in one dimension by two different bridging ligands, 4,4′-bipy and bpa. The thermal stability of compound 1 in the bulk form and nano-sized was studied by thermogravimetric (TG) and differential thermal analysis (DTA). The crystallinity of this compound was studied by X-ray powder diffraction and compared with an XRD simulation of the single crystal data. CdO nanoparticles were obtained by direct calcination at 500 °C and decomposition in oleic acid at 200 °C of the nano-sized compound 1. The obtained cadmium(II) oxide nano-particles were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). 相似文献
24.
Ali Morad Rashidi Roghaye Lotfi Amideddin Nouralishahi Mohammad Ali Khodagholi Masoud Zare Faeghe Eslamipour 《天然气化学杂志》2011,20(6):664-668
Nanoporous carbons were synthesized using furfuryl alcohol and sucrose as precursors and MCM-41 and mordenite as nanoporous templates.The produced nanoporous carbons were used as adsorbent for methane storage.The average pore diameter of the samples varied from 3.9 nm to 5.9 nm and the BET surface area varied from 320m2/g to 824m2/g.The volumetric adsorption experiments revealed that MCM-41 and sucrose had better performance compared with mordenite and furfuryl alcohol,correspondingly.Also,the effect of precursor to template ratio on the structure of nanoporous carbons and their adsorption capacities was investigated.The nanoporous carbon produced from MCM-41 mesoporous molecular sieve partially filled by sucrose shows the best methane adsorption capacity among the tested samples. 相似文献
25.
Dabre R Azad N Schwämmle A Lämmerhofer M Lindner W 《Journal of separation science》2011,34(7):761-772
Several methods for the separation of vitamins on HPLC columns were already validated in the last 20 years. However, most of the techniques focus on separating either fat- or water-soluble vitamins and only few methods are intended to separate lipophilic and hydrophilic vitamins simultaneously. A mixed-mode reversed-phase weak anion exchange (RP-WAX) stationary phase was developed in our laboratory in order to address such mixture of analytes with different chemical characteristics, which are difficult to separate on standard columns. The high versatility in usage of the RP-WAX chromatographic material allowed a baseline separation of ten vitamins within a single run, seven water-soluble and three fat-soluble, using three different chromatographic modes: some positively charged vitamins are eluted in ion exclusion and ion repulsion modes whereas the negatively charged molecules are eluted in the ion exchange mechanism. The non-charged molecules are eluted in a classical reversed-phase mode, regarding their polarities. The method was validated for the vitamin analysis in tablets, evaluating selectivity, robustness, linearity, accuracy, and precision. The validated method was finally employed for the analysis of the vitamin content of some commercially available supplement tablets. 相似文献
26.
Marym Lashanizadehgan Mehdi Rashidi Janet E. Hux Richard J. Puddephatt Samson S.M. Ling 《Journal of organometallic chemistry》1984,269(3):317-322
Reaction of excess MeLi and MeI with [PtCl2SMe2)2] gives the first binuclear tetramethylplatinum(IV) complex [Pt2Me8(μ-SMe2)2]. The characterization of this complex, and its reactions with donor ligands to give cis-[PtMe4L2] (L2 = Ph2PCH2PPh2, Ph2PCH2CH2PPh2, 2,2′-bipyridyl, 1,10-phenanthroline or L = PMe2Ph, PMePh2) are described. 相似文献
27.
28.
Saeed Dinarvand Ahmad Doosthoseini Ensiyeh Doosthoseini Mohammad Mehdi Rashidi 《Nonlinear Analysis: Real World Applications》2010,11(2):1159-1169
The similarity solution for the unsteady laminar incompressible boundary layer flow of a viscous electrically conducting fluid in stagnation point region of an impulsively rotating and translating sphere with a magnetic field and a buoyancy force gives a system of non-linear partial differential equations. These non-linear differential equations are analytically solved by applying a newly developed method, namely the homotopy analysis method (HAM). The analytic solutions of the system of non-linear differential equations are constructed in the series form. The convergence of the obtained series solutions is carefully analyzed. Graphical results are presented to investigate the influence of the magnetic parameter, buoyancy parameter and rotation parameter on the surface shear stresses and surface heat transfer. It is noted that the behavior of the HAM solution for the surface shear stresses and surface heat transfer is in good agreement with the numerical solution given in reference [H. S. Takhar, A. J. Chamkha, G. Nath, Unsteady laminar MHD flow and heat transfer in the stagnation region of an impulsively spinning and translating sphere in the presence of buoyancy forces, Heat Mass Transfer 37 (2001) 397]. 相似文献
29.
M. Hemmati G. H. Rahimi A. B. Kaganj S. Sepehri A. M. Rashidi 《Journal of Macromolecular Science: Physics》2013,52(6):1176-1187
The rheology and morphology of multi-walled carbon nanotube (MWNT)/polypropylene (PP) nanocomposites prepared via melt blending was investigated. The minor phase content of MWNT varied between 0.25 and 8 wt%. From morphological studies using a scanning electron microscopy technique a good dispersion of carbon nanotubes in the PP matrix was observed. The rheological studies were performed by a capillary rheometer, and mechanical properties of the nanocomposites were studied using a tensile and flexural tester. Both PP and its nanocomposites showed non-Newtonian behavior. At low shear rates the addition of MWNT content causes an increase in viscosity; however, viscosity is less sensitive to addition of MWNT content at higher shear rates. Flow activation energy for the nanocomposites was calculated using an Arrhenius type equation. From this calculation it was concluded that the temperature sensitivity of nanocomposites was increased by increasing of nanotube content. An increase in tensile and flexural moduli and Izod impact strength was also observed by increasing the MWNT content. From rheological and mechanical tests it was concluded that the mechanical and rheological percolation threshold is at 1.5 wt%. 相似文献
30.
Rashidi Saman Javadi Parniyan Esfahani Javad Abolfazli 《Journal of Thermal Analysis and Calorimetry》2019,135(1):551-563
Journal of Thermal Analysis and Calorimetry - Employing rough surfaces and nanofluids in solar heater ducts are recognized as effective techniques to improve thermal performances of these devices.... 相似文献