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81.
Zeolite-based photocatalysts were prepared by the sol-gel and deposition methods. The photocatalysts were characterised by
X-ray diffraction, nitrogen adsorption-desorption isotherms, FTIR spectroscopy, scanning electron microscopy and energy-dispersive
X-ray spectrometry. The activity of the prepared photocatalysts was evaluated by the UV-induced degradation of acid blue 92,
a textile dye in common use. The effect of various parameters, such as catalyst concentration, initial dye concentration,
thiosulphate concentration and pH, on the rate and efficiency of the photocatalytic degradation of acid blue 92 was investigated.
The results showed that each parameter influenced the degradation rate and efficiency in a particular way. It was also found
that, under optimised conditions, Ag/AgBr/TiO2/zeolite exhibited the highest photocatalytic performance. A comparison of catalytic activity when exposed to visible light
under the same conditions showed that the photocatalysts containing AgBr had the highest activity. 相似文献
82.
Production of fibroin nanopowder through electrospraying 总被引:1,自引:0,他引:1
Fibroin is a biomaterial and in the powder form, has found applications such as food and cosmetic additive as well as drug
delivery. Various methods have been employed to produce fibroin powder with different particle size range. In this study,
a novel and original application of electrospraying technique capable of producing fibroin nanopowder is presented. Our technique
is based on electrospraying of dilute fibroin solution in formic acid. Moreover, the effect of variables in electrospraying,
namely, concentration of fibroin solution, voltage, feed rate, and needle–collector distance, on average particle size of
fibroin nanopowder has been studied. The result of this study showed that electrospraying is capable of producing fibroin
nanopowder with average particle size as low as 80 nm. In fact in comparison to other methods reported in the literature,
electrospraying alongside with the precipitation method produce fibroin nanopowder with the lowest particle size. However,
nanopowder obtained through electrospraying technique enjoys a more uniform spherical shape and size. As far as the variables
are concerned, it was ascertained that lower concentrations, lower feed rates and longer needle–collector distances lead to
a decrease in the average particle size of fibroin nanopowder. Increasing voltage up to 20 kV decreases the particle size;
but with higher voltages the average particle size increases. FT-IR and XRD studies showed that the fibroin nanopowder has
a β-sheets structure, similar to fibroin filaments but with a lower crystallinity index. 相似文献
83.
Naderi Mahnaz Shamirian Armen Edrisi Mohammad 《Journal of Sol-Gel Science and Technology》2011,58(2):557-563
In the present work nano crystalline copper aluminate (CuAl2O4) has been synthesized by the Pechini method using aqueous solutions containing corresponding metal nitrates. A Taguchi L4 statistical design was employed for investigating the most effective factors on the synthesis conditions and their interactions
and production optimization. Nano crystalline CuAl2O4 particles with crystal size between 17 and 26 nm were obtained. The product characterized by XRD, FT-IR, DLS and TGA. The
morphological properties have investigated using SEM. The photocatalytic degradation was investigated using methyl orange
under the irradiation of visible light. 相似文献
84.
A novel and efficient method for the N-formylation of amines via the reaction of orthoformates and amines is developed. The reactions are mediated by a catalytic amount of molybdate sulfuric acid as a heterogeneous solid acid. 相似文献
85.
In this paper, additive model is used to provide an alternative approach for estimating returns to scale in data envelopment analysis. The proposed model is developed in both stochastic and fuzzy data envelopment analysis. Deterministic (crisp) equivalents are obtained which correspond to the stochastic and fuzzy models. Numerical examples are, also, used to illustrate the proposed approaches. 相似文献
86.
A. Bahraini G. Askari M. Eshaghi Gordji R. Gholami 《Journal of Fixed Point Theory and Applications》2018,20(2):89
Recently Eshaghi et al. introduced orthogonal sets and proved the real generalization of the Banach fixed point theorem on these sets. In this paper, we prove the real generalization of Diaz–Margolis fixed point theorem on orthogonal sets. By using this fixed point theorem, we study the stability of orthogonally \(*\)-m-homomorphisms on Lie \(C^*\)-algebras associated with the following functional equation: for each \(m=1,2,3,4.\). Moreover, we establish the hyperstability of these functional equations by suitable control functions.
相似文献
$$\begin{aligned} \begin{aligned}&f(2x+y)+f(2x-y)+(m-1)(m-2)(m-3)f(y)\\&\quad =2^{m-2}[f(x+y)+f(x-y)+6f(x)]. \end{aligned} \end{aligned}$$
87.
X. Hu W.L. Shelver G.W. Wettstein K. Gholami W.H. Shelver 《Journal of Molecular Structure》2004,686(1-3):7-14
The conformational stability of hexahydropyridobenzodioxin and related derivatives in both protonated and non-protonated forms have been investigated by means of ab initio molecular orbital methods as well as semi-empirical AM1 and PM3 methods. One of the cis conformers (cis2e) has been found to be most stable due to the formation of an intramolecular hydrogen bond, other conformers including the trans isomer cannot form this interaction but are of different stability because of the orientation of the polar oxygens and the nitrogen. The effect of the intramolecular hydrogen bonding on the stability of hexahydropyridobenzodioxin and its methylated derivatives has been examined using various basis sets levels. In protonated form, both the semi-empirical and ab initio calculations give excellent agreement in energetic order; however, different orderings of conformer stabilities are observed by different computational methods in non-protonated form. The results provide insight into the intramolecular hydrogen bonding in computational studies of biologically important molecules. 相似文献
88.
Debarshi Chakraborty Hadi Gholami Aritra Sarkar Leo A. Joyce James E. Jackson Babak Borhan 《Chemical science》2021,12(5):1750
A simple chiroptical solution for the absolute stereochemical determination for asymmetric phosphorus V stereocenters is presented. Strong coordination of the phosphorus oxide with the Zn-metallo center of the racemic host Zn-MAPOL 2 leads to an induced axial chirality of the host, yielding a strong ECCD signal. A mnemonic is proposed to correlate the asymmetry of the guest molecule with the observed ECCD signal.A simple chiroptical solution for the absolute stereochemical determination for asymmetric phosphorus V stereocenters is presented. 相似文献
89.
Ali Reza Harifi‐Mood Aziz Habibi‐Yangjeh Mohammad Reza Gholami 《Journal of Physical Organic Chemistry》2008,21(9):783-788
The second‐order rate constants for cycloaddition reaction of cyclopentadiene with naphthoquinone were determined spectrophotometrically in various compositions of 1‐(1‐butyl)‐3‐methylimidazolium terafluoroborate ([bmim]BF4) with water and methanol at 25 °C. Rate constants of the reaction in pure solvents are in the order of water > [bmim]BF4 > methanol. Rate constants of the reaction decrease sharply with mole fraction of the ionic liquid in aqueous solutions and increase slightly to a maximum in alcoholic mixtures. Multi‐parameter correlation of logk2 versus solute–solvent interaction parameters demonstrated that solvophobicity parameter (Sp), hydrogen‐bond donor acidity (α) and hydrogen‐bond acceptor basicity (β) of media are the main factors influencing the reaction rate constant. The proposed three‐parameter model shows that the reaction rate constant increases with Sp, α and β parameters. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
90.
Mohammad Reza R. Moghaddam All Reza Salemkar Ahmad Gholami 《Southeast Asian Bulletin of Mathematics》2000,24(2):255-261
Let be a variety of groups defined by the set of laws V. In this paper we study the concept of -isologism of groups in terms of -extensions and their connections with the Baer-invariant of groups are also discussed.AMS Subject Classification (2000): primary 20F14, 20F19, secondary 20E10 相似文献