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61.
Chromatographia - WCK 771 is a novel antibacterial drug recently launched in India for the treatment of acute bacterial skin and skin structure infections (ABSSSI). This report describes...  相似文献   
62.
An ecofriendly route has been investigated for the synthesis of 4-(4-nitro-phenyl)-2-phenyl-1,4-dihydro-benzo[4,5]imidazo[1,2-a]pyrimidine-3-carboxylic acid ethyl ester derivatives by one-pot, three-component condensation of ethyl benzoylacetate, aromatic aldehydes, and 2-amino benzimidazole using 260?mol% of citric acid as reaction mediator. Citric acid is an inexpensive, nontoxic, and green medium with smoothly activates the rate of reaction. The synthesized compounds were assessed for in vitro antimycobacterial activity against Mycobacterium tuberculosis H37RV strain using the microplate alamar blue assay (MABA). The results indicate that among all the synthesized compound series, P-4 and P-9 compounds illustrate effective activity with a minimum inhibitory concentration of 25?µg/ml.  相似文献   
63.
As a continuation of our efforts to develop new heterogeneous nanomagnetic catalysts for greener reactions, we identified a Schiff base–palladium(II) complex anchored on magnetic nanoparticles (SB‐Pd@MNPs) as a highly active nanomagnetic catalyst for Suzuki–Miyaura cross‐coupling reactions between phenylboronic acid and aryl halides and for the reduction of nitroarenes using sodium borohydride in an aqueous medium at room temperature. The SB‐Pd@MNPs nanomagnetic catalyst shows notable advantages such as simplicity of operation, excellent yields, short reaction times, heterogeneous nature, easy magnetic work up and recyclability. Characterization of the synthesized SB‐Pd@MNPs nanomagnetic catalyst was performed with various physicochemical methods such as attenuated total reflectance infrared spectroscopy, UV–visible spectroscopy, inductively coupled plasma atomic emission spectroscopy, energy‐dispersive X‐ray spectroscopy, field‐emission scanning electron microscopy, transmission electron microscopy, powder X‐ray powder diffraction, thermogravimetric analysis and Brunauer–Emmett–Teller surface area analysis.  相似文献   
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65.
In this paper, we have obtained plane symmetric cosmological models of thick domain walls with viscous field coupled with electromagnetic field in the framework of Lyra geometry, by using equation of state. Physical and geometrical implications of the models are also discussed in the presence of magnetic field.  相似文献   
66.
Rapid synthesis of triarylcyanurates (2,4,6-triaryloxy-1,3,5-triazine) was carried out by reacting cyanuric chloride with the sodium salt of hydroxyaryl compounds in water using focused microwaves. Environmentally friendly procedure and isolation of pure products in excellent yields are important features of this method.  相似文献   
67.
The exact solution of Einstein-Cartan field equations for static, conformally flat spherically symmetric space-time is derived and it is proved to be Petrov-type D.  相似文献   
68.
Various nitro/nitrile-functionalized benzimidazol-2-ylidene carbene complexes of silver(I) (7ad and 11ad) were synthesized by combination of 1-allyl/1-isopropyl/1-sec-butyl/1-isopentyl-3-(nitro/cyano-benzyl)-3H-benzimidazol-1-ium hexafluorophosphate (6ad and 10ad) with silver(I) oxide in acetonitrile. The compounds were characterized by 1H, 13C NMR, FT-IR, mass spectrometry, and elemental analysis. Additionally, the in vitro antibacterial activity of the N-heterocyclic carbene (NHC) precursors (6ad and 10ad) and their corresponding NHC-silver(I) complexes (7ad and 11ad) were investigated against Gram-positive bacteria Staphylococcus aureus and Gram-negative bacteria Escherichia coli using the qualitative Kirby-Bauer disk diffusion method. All the NHC-silver(I) complexes exhibited medium-to-high antibacterial activity with areas of clearance ranging from 12 mm to 21 mm, while the NHC precursors were inactive against both strains of bacteria.  相似文献   
69.
Metal quinolates, Liq Alq3 Znq2 Mgq2 exhibit efficient luminescence in blue green region and find applications as emission layer in OLEDs. In most of these quinolates the excitation spectra are broad in the range 350 to 410 nm, just short of emission spectra of efficient GaN based blue LEDs. In this paper we report metal quinolates synthesized by slightly modified method in which the excitation gets extended beyond 450 nm so that there is better overlap between emission spectra of blue LED and the excitation spectra. Therefore these phosphors may be used for PC-LED applications.  相似文献   
70.
提出了一种新的带有二元连接函数的广义半参数模型,即二元连接模型(简称为BLM).使用轮廓似然方法估计模型的参数和非参数部分,并给出了计算算法.证明了所得的未知参数的估计量为n~(1/2)-相合,渐近正态且具有渐近最小方差,给出了实际数据分析和模拟研究,最终采用局部功效方法来检验非参数部分的线性性.  相似文献   
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