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111.
Prof. Dr. M. Salih Ağırtaş İlkay Gümüş Veysi Okumus Abdurrahman Dundar 《无机化学与普通化学杂志》2012,638(11):1868-1872
4, 4′‐(1, 4‐Phenylenebis(oxy)diphthalonitrile was synthesized by reaction of hydroquinone with 4‐nitrophthalonitrile. Binuclear metallophthalocyanines 2–4 were obtained by the reaction between 4, 4′‐(1, 4‐phenylenebis(oxy)diphthalonitrile and 4‐(benzo [d] 1 , 3 dioxol‐5‐ylmethoxy)phthalonitrile in the presence of metal salts. These new compounds were characterized by using elemental analysis, FTIR, 1H‐NMR and UV/Vis spectroscopic data. Thermal properties of phthalocyanines 2‐4 were investigated by TG and DTA. In addition, antioxidant properties of compounds II , 3 and 4 were investigated. Their radical‐scavenging capacity and chelating effects was fully studied. The maximum 1, 1‐diphenyl‐2‐picrylhydrazyl radicals (DPPH) were obtained from compound 3 . Chelating effects on ferrous ions were 91.6 % at concentration of 100 mg L–1 with compound II . 相似文献
112.
Farook Adam Muazu Samaila Batagarawa Kasim Mohammed Hello Salih S. Al-Juaid 《Chemical Papers》2012,66(11):1048-1058
A one-pot method was employed to immobilize sulfonic acid onto silica obtained from rice husk ash using 3-(mercaptopropyl)trimethoxysilane to form a solid catalyst denoted as RHASO3H. BET measurements of the catalyst showed the surface area to be 340 m2 g?1 with the average pore volume of 0.24 mL g?1 and the pore diameter of 2.9 nm. Acidity test of cation exchange capacity and pyridine adsorption studies revealed the presence of Br?nsted acid sites on the catalyst surface. The catalyst was used in the acetalization reaction of glycerol with benzaldehyde. Under optimized conditions, the reaction showed the maximum conversion of 78 % after 8 h with 67 % selectivity towards the five membered ring isomer. Variation in the glycerol concentration had a significant effect on the reactants conversion. A single crystal X-ray study of one of the products proved the existence of a unique trimer formed by hydrogen bonding by the six-membered cis-isomer. The catalyst was several times recycled without any loss of its catalytic activity. 相似文献
113.
In this work, Z3-graded quantum (h, j)-superplane is introduced with a help of proper singular g matrix and a Z3-graded calculus is constructed over this new h-superplane. A new Z3-graded (h, j)-deformed quantum (super)group is constructed via the obtained calculus. 相似文献
114.
Industrial development and applications of plant oils and their biobased oleochemicals 总被引:1,自引:0,他引:1
In the concepts for new products, performance, product safety, and product economy criteria are equally important. They are taken into account already when the raw materials base for a new industrial product development is defined. Here, renewable resources gain-again after the earlier “green trend” in the 1980s—increasing attention as an alternative raw materials source compared to fossil feedstock. The industrial use of carbohydrates, proteins, and plant oils aligns perfectly with the principles of Responsible Care and is an important part of green chemistry and sustainability in general. Since the 1950s, oleochemistry has grown to a major research and technology area in several institutions and industries. A large variety of products based on fats and oils have been developed since then for different uses, such as specialties for polymer applications, biodiesel, surfactants, emollients for home and personal-care industries, pesticides and biodegradable mineral oil replacements for lubricants. However, at present it seems that the use of renewable resources, especially plant oils, has to compete more and more with the increasing demand for bioenergy, which could cause an unbalanced supply and demand in the future or even a threat for the increasing demand for food in certain areas of the world. 相似文献
115.
This paper presents significant correlations of the Bond parameter (work index, Wi and grindability, G) and the breakage parameters (specific rate of breakage, Si and the fineness value, γ) with the point load index (Is(50)). The experimental results obtained from calcite, barite, colemanite and bauxite samples have demonstrated that the Bond and breakage parameters were closely correlated with the point load index. That is, the values of G, Si and aT parameters decreased with the increase in the values of the point load index; however, the γ parameter of Bi,j increased with increasing Is(50) values. 相似文献
116.
This paper is concerned with the dynamic assignment of servers to tasks in queueing networks where demand may exceed the capacity
for service. The objective is to maximize the system throughput. We use fluid limit analysis to show that several quantities
of interest, namely the maximum possible throughput, the maximum throughput for a given arrival rate, the minimum arrival
rate that will yield a desired feasible throughput, and the optimal allocations of servers to classes for a given arrival
rate and desired throughput, can be computed by solving linear programming problems. We develop generalized round-robin policies
for assigning servers to classes for a given arrival rate and desired throughput, and show that our policies achieve the desired
throughput as long as this throughput is feasible for the arrival rate. We conclude with numerical examples that illustrate
the points discussed and provide insights into the system behavior when the arrival rate deviates from the one the system
is designed for. 相似文献
117.
We present a differential calculus on the extension of the quantum plane obtained by considering that the (bosonic) generator x is invertible and by working with polynomials in ln x instead of polynomials in x. We construct the quantum Lie algebra associated with this extension and obtain its Hopf algebra structure and its dual Hopf algebra. 相似文献
118.
Biliverdin is a useful component in various aspects of biochemistry and biosynthesis, but its synthetic preparation is often
long-winded. Micro-production (and subsequent isolation) by solar photolysis and gamma radiolysis of bilirubin provides rapid
in vitro generation. Both methods are competitive, and this article discusses their merits and limitations for application
in biosynthetic research. The investigation assumed a comparative study to evaluate the relative potential of the photolytic
and radiolytic phenomena in this respect. The calculated rate of incident energy in the case of solar photolysis was roughly30.4.10-2 W, and about 5.70.10-4 W during gamma-irradiation (from a 137Cs source). In both cases the bilirubin (40 μM) degradation was pronounced in the initial few minutes of exposure, producing
respective depletion rates of approximately 6.8 μM/min and 2.4 μM/min. Overall, both applications showed declining bilirubin
concentrations close to 90%, after about 30 minutes. However, the corresponding production of biliverdin was higher by about
50% in the photolytic application. To account for heat-up effects in the photolytic application, thermal effects were studied
up to 65 °C, and it was found that, as a result of this, a reduction in bilirubin concentration of about 40% was encountered.
The species of interest were monitored spectrophotometrically, and the composite results showed that regulated production
of biliverdin is possible under certain conditions.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
119.
Salih H.A. Tripathi V.K. Pandey B.K. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》2003,31(3):324-328
The second-harmonic generation of an intense self-guided right circularly polarized laser beam in a magnetized plasma is investigated. The laser imparts oscillatory velocity to electrons and exerts a radial ponderomotive force on them to create a depleted density channel. The critical power for self-focusing shows huge reduction as electron cyclotron frequency approaches the laser frequency (/spl omega//sub c/ /spl rarr/ /spl omega/). In the presence of the self-created radial density gradient, the laser drives a density perturbation at the fundamental frequency. The density perturbation beats with the oscillatory velocity to produce a second harmonic current density, driving second harmonic radiation copropagating with the laser. The second harmonic, however, is azimuthally asymmetric with /spl theta/-variation as exp(i/spl theta/). Its amplitude shows resonant enhancement as /spl omega//sub c/ /spl rarr/ /spl omega/. 相似文献
120.
Mohamed M. Ibrahim Salih S. Al-Juaid Q. Mohsen 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):2324-2332
Reactions of the ligand 2-mercapto-1-cyclohexylimidazole (Hmimchexyl) with both zinc(II) and cadmium(II) bromides in ethanol solutions afforded 2:1 complexes of the type [M(Hmimchexyl)2(Br)2] (M = Zn 1, and Cd 2) with an MBr2S2 configurations. Spectroscopic evidence (FT-IR and 1H-13C NMR) confirms that the exocyclic thione sulfur atoms are the donors in both complexes. Complex 1 crystallizes in a monoclinic system, space group C2/c, a = 16.180(3), b = 10.817(5), c = 13.602(3); α = 90, β = 106.754(17), γ = 90; Z = 4; R1 = 0.0229, wR2 = 0.0554. The coordination geometry about the zinc(II) atom is distorted tetrahedral with average Zn-S and Zn-Br bond lengths of 3.3418(8) and 2.4017(6) Å, respectively. The bromide ions form intermolecular N–H…Br hydrogen bonding with the thione NH groups of the ligand molecule. 相似文献