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51.
52.
T. I. Belykh V. P. Bulatov E. N. Yas’kova 《Computational Mathematics and Mathematical Physics》2008,48(1):16-29
Chebyshev points of bounded convex sets, search algorithms for them, and various applications to convex programming are considered for simple approximations of reachable sets, optimal control, global optimization of additive functions on convex polyhedra, and integer programming. The problem of searching for Chebyshev points in multicriteria models of development and operation of electric power systems is considered. 相似文献
53.
The one-pot four-component synthesis of highly functionalized fused hydroxyl dihydropyrroles and dihydropyrazines from readily available diamines, 1,1-bis (methylsulfanyl)-2-nitroethene, phenylglyoxal monohydrates, and C-H acids have been developed. This strategy provides an efficient, catalyst-free approach for easy access to various new hydroxyl-dihydropyrrole and dihydropyrazine rings in good to high yields. The products were confirmed by 1H and 13C NMR, IR, mass, and X-ray crystal structure analyses. 相似文献
54.
Bayat Zeinab Saeedzadeh Elham Vahidfar Nasim Sadeghi Mahdi Farzenefar Saeed Daha Fariba Johari Salehi Yalda 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(2):691-700
Journal of Radioanalytical and Nuclear Chemistry - Radiocolloides are essential for the detection of metastatic lymph nodes in breast cancer. In this study [67Ga]Ga-phytate, as an long-lived... 相似文献
55.
Seyyed Javad Sabounchei Vida Jodaian Sadegh Salehzadeh Sepideh Samiee Alireza Dadrass Mehdi Bayat Hamid Reza Khavasi 《Helvetica chimica acta》2010,93(6):1105-1119
Reactions of phosphonium ylides (4‐MeC6H4)3PCHC(?O)(2‐C4H3S) (tptpy), Ph3PCHC(?O)(2‐C4H3O) (fppy), and (4‐MeC6H4)3PCHC(?O)(4‐BrC6H4) (bbtppy) with HgX2 (X=Cl, Br, and I) in equimolar ratios in MeOH as solvent leads to the binuclear products 1 – 3 (Scheme 1). The bridge‐splitting reaction of the binuclear complex [{HgI2(bbtppy)}2] ( 3c ) by DMSO yields the mononuclear complex [HgI2?(bbtppy) (DMSO)] ( 3d ) (Scheme 2). This bridge‐splitting reaction can also be a method for the synthesis of mononuclear products. C‐Coordination of the ylide and O‐coordination of DMSO are demonstrated by a single‐crystal X‐ray‐analysis of the mononuclear complex 3d . Characterization of the obtained compounds was also performed by means of elemental analysis and IR and 1H‐, 31P‐, and 13C‐NMR spectroscopy. A theoretical study of some HgII complexes with phosphonium ylides is also reported. 相似文献
56.
The theoretical formulation for bending analysis of functionally graded (FG) rotating disks based on first order shear deformation theory (FSDT) is presented. The material properties of the disk are assumed to be graded in the radial direction by a power law distribution of volume fractions of the constituents. New set of equilibrium equations with small deflections are developed. A semi-analytical solution for displacement field is given under three types of boundary conditions applied for solid and annular disks. Results are verified with known results reported in the literature. Also, mechanical responses are compared between homogeneous and FG disks. It is found that the stress couple resultants in a FG solid disk are less than the stress resultants in full-ceramic and full-metal disk. It is observed that the vertical displacements for FG mounted disk with free condition at the outer surface do not occur between the vertical displacements of the full-metal and full-ceramic disk. More specifically, the vertical displacement in a FG mounted disk with free condition at the outer surface can even be greater than vertical displacement in a full-metal disk. It can be concluded from this work that the gradation of the constitutive components is a significant parameter that can influence the mechanical responses of FG disks. 相似文献
57.
Bayat M Vasheghani MM Razavi N 《Journal of photochemistry and photobiology. B, Biology》2006,83(2):87-93
This paper presents the results of a study on the effects of low-level helium-neon laser therapy (LL He-Ne LT) on the healing of burns. Seventy-eight adult male rats, having been subjected to third-degree burns, were randomly divided into four groups: two laser treated groups (n=20, each), one control group (n=19) and one nitrofurazone treated group (n=19). In the two laser treated groups, the burns were treated on a daily basis with LL He-Ne LT with an energy density of 1.2 and 2.4 J/cm(2), respectively. The response to treatment was assessed histologically at 7, 16 and 30 days after burning, and microbiologically at day 15. Analysis of variance showed that the mean of blood vessel sections in the 1.2J/cm(2) laser group was significantly higher than those in the other groups and the mean of the depth of new epidermis in the 2.4 J/cm(2) laser group on day 16 was significantly lower than in the nitrofurazone treated group (P=0.025, P=0.047, respectively). When Staphylococcus aureus and Pseudomonas aeruginosa grew in more than 50% of samples obtained from control group, there were no S. aureus and P. aeruginosa in the samples of 2.4 J/cm(2) laser group. It is concluded that LL He-Ne LT induced the destruction of S. aureus and P. aeruginosa in third-degree burns of rats, yet at the same time our histological findings showed that LL He-Ne LT caused a significant increase in the mean of blood vessel sections on day 7 after third degree burns and a decrease in the mean of the depth of new epidermis on day 16 after the same burns in rats. 相似文献
58.
59.
The reagent bis(isovalerylacetone)ethylenediimine(H2IVA2en) has been examined for HPLC separation and UV determination of cobalt, copper, iron and platinum using off-line precolumn derivatization and extraction in chloroform. The complexes of cobalt(II), cobalt(III), iron(II), iron(III) and the reagent have been subsequently separated on a Microsorb C-18 column. The complexes were eluted isocratically using ternary mixtures of methanol/water/acetonitrile. Detection was achieved by UV monitoring. Detection limits for Co(II), Co(III), Fe(II) and Fe(III) were 2.5–5.0 ng/injection, based on 0.5–1.0 g/ml with 5 l/injection. The concentration of cobalt(II) and cobalt(III) in aqueous solution have been determined. The presence of oxovanadium(IV), platinum(II), and nickel(II) did not affect the determinations. The HPLC method developed has been applied to the determination of cobalt, copper, iron and platinum in pharmaceutical preparations at the 30 g/g to 15 mg/g level and the obtained results were compared to those of atomic absorption spectrometry. 相似文献
60.
The direct implementation of GIAO and CSGT methods for calculation of 13C isotropic shielding constants of fully protonated forms of six tripodal tetraamine ligands tren, pee, ppe, tpt, epb and ppb at the Hartree‐Fock level of theory are presented. The shielding constants were determined using hybrid methods (including a mixture of Hartree‐Fock exchange and DFT exchange‐correlation) and are close to the experimental data. A splayed‐like conformation was considered for fully protonated forms of all ligands, and it was confirmed that this is the most stable conformation for the latter form of such ligands. A good linear correlation between the calculated chemical shielding at gas‐phase and experimental shift values in D2O solution was obtained. 相似文献