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71.
Some solutions of 5D conformally flat extension of induced-matter theory are derived. The corresponding induced matter solutions
on the 4D hypersurfaces and their properties are presented. 相似文献
72.
A. Nilchi T. Shariati Dehaghan S. Rasouli Garmarodi 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(3):2111-2115
A simple and reliable method for rapid extraction and determination of uranium and thorium using octadecyl-bonded silica modified with Cyanex 302 is presented. Extraction efficiency and the influence of various parameters such as aqueous phase pH, flow rate of sample solution and amount of extractant has been investigated. The study showed that the extraction of uranium and thorium increase with increasing pH value and was found to be quantitative at pH 6; and the retention of ions was not affected significantly by the flow rate of sample solution. The extraction percent were found to be 89.55 and 86.27 % for uranium and thorium, respectively. The maximal capacity of the cartridges modified by 30 mg of Cyanex 302 was found to be 20 mg of uranium and thorium. The method was successfully applied to the extraction and determination of uranium and thorium in aqueous solutions. The percentage recovery of uranium and thorium in a number of natural as well as seawater samples of Iran were also investigated and found to be in the range of 85–95 %. 相似文献
73.
Adsorption of selected ions on hydrous cerium oxide 总被引:2,自引:0,他引:2
A. Nilchi M. Yaftian G. Aboulhasanlo S. Rasouli Garmarodi 《Journal of Radioanalytical and Nuclear Chemistry》2009,279(1):65-74
Hydrous cerium oxide was synthesized and laboratory study was conducted to address its applicability for decontamination of
barium, strontium, molybdenum, europium, iodine, samarium and cesium ions from radioactive liquid wastes using radiotracer
technique. The adsorption of Ba(II), Sr(II), Mo(II), Eu(II), I(I), Sm(III) and Cs(I) on hydrous cerium oxide has been investigated
as a function of pH, concentration and temperature of the adsorptive solution and the result obtained show that these parameters
affect the extent of adsorption. The ion-exchange capacity decreased at higher temperatures which could be due to decrease
of active sites as well as hydrophilic properties of surface adsorbent. Hydrous cerium oxide shows relatively high adsorption
in acidic and neutral media towards the radiotracers studied, which can be attributed to large hydrated radius and ion exclusion
effect. 相似文献
74.
75.
Issa Yavari S. Zahra Sayyed-Alangi Rahimeh Hajinasiri Hadi Sajjadi-Ghotbabadi 《Monatshefte für Chemie / Chemical Monthly》2009,28(8):209-211
Abstract
A simple one-pot synthesis of functionalized ethyl 1,3-thiazole-5-carboxylates from the reaction of 2-chloro-1,3-dicarbonyl compounds with thioureas or thioamides in the presence of 1-butyl-3-methylimidazolium trifluoromethanesulfonate is described. 相似文献76.
Issa Yavari Nasir Iravani S. Zahra Sayyed-Alangi Rahimeh Hajinasiri 《Monatshefte für Chemie / Chemical Monthly》2009,35(1):1199-1204
Abstract
An efficient synthesis of alkyl acylcarbamodithioates by reaction of acid chlorides with ammonium thiocyanate in the presence of thiols is described. The unusually large values of 5 J FH = 12–15 Hz, observed for alkyl (2-fluorobenzoyl)carbamodithioates provide information about Ar–C–N–H torsion in these compounds. 相似文献77.
It has been shown that most of the previously reported empirical rate equations for kinetics of adsorption at the solid/solution interface show high relative errors at the initial times of adsorption. In the present work we made a modification onto pseudo-first-order and pseudo-second-order models and presented a new empirical rate equation, called the modified pseudo-n-order (MPnO) model. The results of fitting to the experimental data show that the MPnO model has low relative errors in the whole range of adsorption time. 相似文献
78.
We investigate the connection between the entanglement generated by expanding universe and the cosmological parameters. We
show that the faster the universe expands and the larger the total volume results the higher degree of entanglement. 相似文献
79.
In this paper we study the notion of injectivity in the category Pos-S of S-posets for a pomonoid S. First we see that, although there is no non-trivial injective S-poset with respect to monomorphisms, Pos-S has enough (regular) injectives with respect to regular monomorphisms (sub S-posets). Then, recalling Banaschewski’s theorem which states that regular injectivity of posets with respect to order-embeddings and completeness are equivalent, we study regular injectivity for S-posets and get some homological classification of pomonoids and pogroups. Among other things, we also see that regular injective S-posets are exactly the retracts of cofree S-posets over complete posets. 相似文献
80.
Saeed Rasouli Heikalabad Mahya Rahimpour Gadim 《International Journal of Theoretical Physics》2018,57(6):1733-1747
The quantum-dot cellular automata (QCA) can be replaced to overcome the limitation of CMOS technology. An arithmetic logic unit (ALU) is a basic structure of any computer devices. In this paper, design of improved single-bit arithmetic logic unit in quantum dot cellular automata is presented. The proposed structure for ALU has AND, OR, XOR and ADD operations. A unique 2:1 multiplexer, an ultra-efficient two-input XOR and a low complexity full adder are used in the proposed structure. Also, an extended design of this structure is provided for two-bit ALU in this paper. The proposed structure of ALU is simulated by QCADesigner and simulation result is evaluated. Evaluation results show that the proposed design has best performance in terms of area, complexity and delay compared to the previous designs. 相似文献