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61.
G.Rezaei Behbehani A.A.Saboury M.Mohebbian S.Tahmasbi Sarvestani M.Poorheravi 《中国化学快报》2009,20(11):1389-1392
Cyanide ion was studied as an inhibitor of Jack bean urease at 300 K in 30 mmol/L tris buffer,pH 7.The inhibition was investigated by isothermal titration calorimetry(ITC).The extended solvation model was used for CN~- + JBU interaction over the whole range of CN~- concentrations.The binding parameters recovered from the solvation model were attributed to the cyanide ion interaction.It was found that cyanide ion acted as a non-cooperative inhibitor of urease,and there is a set of 12±0.12 identical and in... 相似文献
62.
Heat and Mass Transfer - Effects of dissipation on heat transfer due to second order effects of longitudinal curvature, transverse curvature, displacement speed, external vorticity and stagnation... 相似文献
63.
64.
In this paper, we establish the equivalence between the generalized nonlinear mixed variational inequalities and the generalized resolvent equations. This equivalence is used to suggest and analyze a number of iterative algorithms for solving generalized variational inequalities. We also discuss the convergence analysis of the proposed algorithms. As special cases, we obtain various known results from our results. 相似文献
65.
66.
An account is given of a new formalism for calculating energy levels in molecules using techniques that derive from the band theory of metals. After showing how the molecular potential may be transformed into a cellular potential we define the basis set of muffin-tin orbitals and discuss some of their properties. The relationship between the scattered wave formulation of Johnson, which is restricted to muffin-tin potentials, and our more general approach based on the use of a linear combination of muffin-tin orbitals (L.C.M.T.O.) is explicitly indicated. We then show how the properties of the muffin-tin orbitals, together with the technique of cellular integration, give rise to a hamiltonian matrix. This matrix is as general as, but simpler than that obtained by the use of atomic orbitals, and it is linear in energy and therefore computationally faster than the secular matrix of the scattered wave method. 相似文献
67.
Wan Aini Wan Ibrahim Dadan Hermawan Mohamed Noor Hasan Hassan Y. Aboul Enein M. Marsin Sanagi 《Chromatographia》2008,68(5-6):415-419
A rapid estimation of octanol–water partition coefficient (log P ow) was developed for triazole fungicides by micellar electrokinetic chromatography (MEKC). Five standard compounds with known log P ow values from 2.9 to 4.3 (cyproconazole, bromuconazole, epoxiconazole, bitertanol and difenoconazole) were used for constructing the calibration curve of the log P ow against the MEKC retention factor, log k. A linear relationship was achieved between log P ow and log k, in the MEKC system containing 40 mM sodium deoxycholate (SDC) and 4 mM borate buffer at pH 9.3, with a correlation of determination, r 2 = 0.9905. The log P ow values of four test compounds of triazole fungicides (triadimenol, myclobutanil, propiconazole and penconazole) were calculated based on the log k values measured by MEKC and the slope and intercept of the calibration curve. This MEKC method can give good estimation of the log P ow of the four test compounds of triazole fungicides with the differences between the literature log P ow values and estimated log P ow from the MEKC method were from 0.15 to 0.23 log units. 相似文献
68.
69.
H. M. Noor ul Huda Khan Asghar Yi Tan Shuang Shi Dachuan Jiang Shiqiang Qin Jiao Liao Shutao Wen Wei Dong Yao Liu 《Applied Physics A: Materials Science & Processing》2014,115(3):753-757
Small amounts of multicrystalline silicon were melted in an electron beam furnace in different experimental conditions in order to investigate the oxygen evaporation behavior during the electron beam melting (EBM) process. The oxygen content level before and after EBM was determined by secondary ion mass spectroscopy. The oxygen content was reduced from 6.177 to 1.629 ppmw when silicon was melted completely at 15 kW with removal efficiency up to 73.6 %. After that, it decreased continually to <0.0517 ppmw when the refining time exceeded 600 s with a removal efficiency of more than 99.08 %. During the melting process, the evaporation rate of silicon is 1.10 × 10?5 kg/s. The loss of silicon could be reduced up to 1.7 % during oxygen removal process to a desirable figure, indicating EBM is an effective method to remove oxygen from silicon and decrease the loss of silicon. 相似文献
70.
Osman Ayop Mohamad Kamal A. Rahim Noor Asniza Murad Huda A. Majid 《Applied Physics A: Materials Science & Processing》2014,117(2):651-656
This paper presents the analysis of circular ring metamaterial absorber with the existing of copper lines. The structure is designed using lossy FR4 substrate with thin copper layers. The circular ring shape with copper lines is printed on the top surface of FR4 substrate, while at the bottom surface is printed with full copper ground plane. Parametric study is done to investigate the effect of copper lines on the resonance frequency. From the simulation, the circular ring metamaterial absorber with vertical copper lines can resonates at lower frequency, but this structure is polarized sensitive. This drawback can be improved by adding horizontal copper lines together with the vertical copper lines. The circular ring structure with vertical and horizontal copper lines is not only polarization insensitive, but it can works at wide operating angle of incident waves. 相似文献