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31.
Synthesis of substituted phenanthridinones and dibenzoazepinones has been realized from 2-halo-benzamides in the presence of potassium tert-butoxide and a catalytic amount of 1,10-phenanthroline or AIBN. This new carbon-carbon bond forming reaction gives direct access to various biaryl lactams containing six- and seven-membered rings chemoselectively. Carbon-carbon coupling seems to proceed by the generation of a radical in the amide ring which leads to C-H arylation of aniline.  相似文献   
32.
Kumar  Avinash  Rathi  Ekta  Kini  Suvarna G. 《Structural chemistry》2020,31(1):141-153
Structural Chemistry - Repurposing of ‘old’ drugs to treat both common and rare diseases has garnered huge attention of the researchers because of the high attrition rates and...  相似文献   
33.
We have investigated the magnetic phase diagram of polycrystalline and single-crystal La1−xSrxMnO3 near 0.46≤x≤0.50. It turns out that for x<0.48, the polycrystalline material is ferromagnetic (FM), but for x≥0.48, incipient charge ordering takes place along with antiferromagnetism. At x=0.48, the ferromagnetic-antiferromagnetic phase transition in ceramics occurs at less than 85 kOe but requires significantly larger field for increasing x. These observations are in contrast to what is found in the single crystals, which are all FM.  相似文献   
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We report measurements on magnetic resonance in a number of transition metal-glass former complexes. Data were taken over a wide range of frequencies (2–35 GHz) and temperatures (2–300 K). In the ferromagnetic regime all the systems have a term in their linewidth which points strongly to noncolinearity of spin in glassy magnets even in a nominally saturated state. At low temperatures, in the reentrant alloys, there is a characteristic exponential term describing the increase in linewidth, with reducing T. Such a contribution appears in most random spin systems. There is no adequate microscopic picture to account for many of the results.  相似文献   
36.
The fixed dose combination of azilsartan medoxomil potassium and chlorthalidone has been introduced for the effective treatment of hypertension. In the present work a rapid, simple and accurate stability indicating ultra HPLC assay method has been developed. The separation of azilsartan medoxomil, chlorthalidone and their degradation products were accomplished on an Acquity UPLC BEH C18 (100 mm × 2.1 mm, 1.7 μm) column using mobile phase combination of 0.02% trifluoroacetic acid in water and acetonitrile in gradient mode. The forced degradation products were identified using liquid chromatography?electrospray ionisation-quadrupole time of flight-tandem mass spectrometry (LC?ESIQTOF–MS/MS) and accurate mass experiments. The in silico toxicities of the degradation products for both the drugs were evaluated. The proposed method was validated as per the ICH Q2 (R1) guideline for selectivity, linearity, precision, accuracy and robustness.  相似文献   
37.
In view of the advantages of employing heterometallic alkoxides as precursors for ceramic materials by the sol-gel process, efforts are being made to develop novel routes for their synthesis and to design single source precursors suited to the final targeted material. Three such new pathways are briefly presented in this paper: (i) varying the ratio of constituent metals; (ii) dissolution of metal chlorides in alkoxides of tetravalent metals; and (iii) reactions of acidic protons of metal glycolate derivatives with alkoxides of another metal yielding derivatives containing other alkoxometallates in cationic form.  相似文献   
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Journal of Solid State Electrochemistry - Metallic lead (Pb) has been electrodeposited on FTO substrate at room temperature from aqueous nitrate solution under constant applied potential in the...  相似文献   
40.
We have studied the effects of thermal cycling and annealing on the Hall resistivity ?H and electrical resistivity ? of an amorphous magnetic material, Metglas 2826A. Thermal cycling up to 600 K has no significant effect on ? but changes ?H, especially at T > 300 K. Annealing at higher temperatures Ta affects ?H more strongly that it influences ?. For Ta = 650 K the Curie temperature jumps by ~300 K and this, combined with X-ray data, is regarded as being symptomatic of the onset of crystallization. It is demonstrated that, for a fixed T, the variation of the extraordinary Hall coefficient R1 is simply correlated with that of ? for both the amorphous material and the annealed (crystallized) specimens. Furthermore, for a given Ta, the variations of R1 and ? as functions of temperature exhibit the same formal relationship. The temperature dependence of ? in the annealed specimens is rendered plausible in terms of recent theories of disordered materials. Room-temperature studies of electron spin resonance and the field dependence of the magnetization are also reported.  相似文献   
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