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81.
Chen Jiawei Al-Homidan Suliman Ansari Qamrul Hasan Li Jun Lv Yibing 《Journal of Optimization Theory and Applications》2021,189(1):221-243
Journal of Optimization Theory and Applications - In this paper, we study robust necessary optimality conditions for a nondifferentiable complex fractional programming with uncertain data. A robust... 相似文献
82.
A lanthanum(III) complex of catechin has been synthesized and characterized by elemental analysis, molar conductance, UV-Vis spectra, infrared spectra, thermal analysis, and 1H NMR. The complex behaves as a nonelectrolyte in methanol solvent. The spectral and thermal properties of the complex are examined. A thermogravimetric (TGA) study showed the hydrated nature of the complex. 1H NMR spectra of the lanthanum and the catechin (CT) ligands measured in CD3OD-d4 also show metal ligand coordination. The lanthanum–catechin complex shows bright luminescence in methanol solution. The interaction of the complex with calf thymus DNA has been investigated by absorption and emission spectroscopic measurements. Experimental spectral results suggest CT–DNA binding with catechin complex via an intercalative mode. 相似文献
83.
Summary In this theoretical work, we consider the geometrical, electronic and energetic properties of some lithium and beryllium derivatives. The standard heats of formation of these compounds have been calculated at the MP4=SDTQ/6-31+G(2df, p)//MP2=FULL/6-31G(d, p) level. The values obtained at this level of the theory are also compared with the heats of formation deduced from a composite procedure in which it is assumed that some corrections can be treated separately and combined in an additive manner. We find that the values determined with the complete 6-31+G(2df, p) basis set are the more accurate. 相似文献
84.
In this study, a simple, fast, accurate and sensitive spectrophotometric method has been developed for the determination of tranexamic acid in bulk and pharmaceutical preparations. The method is based on the reaction of ninhydrin with the primary amino group of tranexamic acid in the basic medium at pH 8.0. The reaction produces a bluish-purple color which absorbs maximally at 565 nm. Beer's law was obeyed in the range of 3-40 microg ml(-1) with molar absorptivity of 5.093 x 10(3) L mol(-1) cm(-1). The effects of various factors such as temperature, heating time, concentration of reagent, color stability and interferences were investigated to optimize the procedure. The results have been validated analytically and statistically. The proposed method has been applied for the determination of tranexamic acid in bulk and pharmaceutical preparations with good results. 相似文献
85.
86.
A new automated torsional pendulum is described. It uses a single photocell for the measurement of the period of oscillation and the logarithmic decrement. Data acquisition, data processing and temperature control are all performed by a single microcomputer. The result is that the instrument can be produced and operated more cheaply than before.The principles behind the design, the method of determining the shape factor, the calibration procedure and the software are discussed. Examples are given to illustrate the use of this instrument. A practical limitation is that the loss tangent should not exceed about 3. 相似文献
87.
The results of a variation after angular momentum projection calculation with axial Nilsson-BCS-like intrinsic wave functions and a cranked Hartree-Fock-Bogoliubov calculation for the back-bending region in 158Er are reported. The moment-of-inertia values in the former are closer to the experimental results. 相似文献
88.
A new angular momentum expansion of level energies of ground-state band of even-even nuclei has been obtained which is found to converge rapidly even for the most back-bending nuclei. Attempts have been made to interpret the parameters and calculate them microscopically. It is found that nuclear structure in the forward bending region is quite different compared to that in the back-bending region. 相似文献
89.
A theoretical study of substituent effects on 1,3-dipolar cycloadditions has been carried out by the LCAO-SCF-MO method. The potential energy hypersurfaces for ten reactions and the electronic and energetic properties of the transition states have been investigated. 相似文献
90.