Acid-catalysed Hydrolysis of N-Phenyl-n-butyrohydroxamic Acid

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Interfacial strain in AlxGa1–xAs layers on GaAs

Detailed analysis of x-ray rocking curves was used to determine the depth profile of strain and composition in a 2500-Å-thick layer of AlxGa1–xAs grown by metalorganic chemical vapor deposition on 100 GaAs. The x value and layer thickness were in good agreement with the values expected from growth parameters. The presence of a transition region, 280 Å thick, was detected by the rocking curve. In this region, the Al concentration varies smoothly from 0 to 0.87. Measurement and control of the sharpness of such interfaces has important implications for heterojunction devices

Extractive Spectrophotometric Determination of Vanadium(V) with N-p-Chlorophenyl-2-naphthohydroxamic Acid and Investigation of Its Solid Complex

A simple, selective and sensitive method for the extractive spectrophotometric determination of vanadium(V) using N-p-chlorophenyl- 2-naphthohydroxamic acid (CP-2-NHA) is described. Vanadium( V) is quantitatively extracted from 3-8.4 M HCl as a violet complex with CP-2-NHA into chloroform. Beer\u27s law is applicable in the concentration range 34 and 224 fig of vanadium(V) per 25 ml of chloroform extract. The Sandell sensitivity of the system is 0.0089 μg/cm2 at 530 nm. The method has been satisfactorily employed for the determination of vanadium in steel. The solid complex, VOCI (C11H11N02Cl)2, was prepared and characterised by melting point, elemental analysis, visible and infrared spectra

Late Quaternary stratigraphic development in the lower Luni, Mahi and Sabarmati river basins, Western India

This study reviews the Quaternary alluvial stratigraphy in three semi-arid river basins of western India i.e., lower Luni (Rajasthan), and Mahi and Sabarmati (Gujarat alluvial plains). On the basis of OSL chronologies, it is shown that the existing intra-valley lithostratigraphic correlations require a revision. The sand, gravel and mud facies are present during various times in the three basins, however, the fluvial response to climate change, and the resulting facies associations, was different in the Thar desert as compared to that at the desert margin; this makes purely lithostratigraphic correlations unviable. It is further shown that the rivers in the Thar desert were more sensitive to climate change and had small response times and geomorphic thresholds as compared to the desert-margin rivers. This is illustrated during the early OIS 1, when the Luni river in the Thar desert was dynamic and showed frequent variations in fluvial styles such as gravel bedload braided streams, sand-bed ephemeral streams and meandering streams, all followed by incision during the early Holocene. The coeval deposits in Sabarmati, however, only show a meandering, floodplain-dominated river. Late Quaternary alluvial deposits in these basins unconformably overlie some older deposits that lack any absolute chronology. Based on the facies types and their associations, and the composition and architecture of the multistoried gravel sheets in the studied sections, it is suggested that older deposits are of pre-Quaternary age. This hypothesis implies the presence of a large hiatus incorporating much of the Quaternary period in the exposed sections

GASP XVIII: Star formation quenching due to AGN feedback in the central region of a jellyfish galaxy

We report evidence for star formation quenching in the central 8.6 kpc region of the jellyfish galaxy JO201 which hosts an active galactic nucleus, while undergoing strong ram pressure stripping. The ultraviolet imaging data of the galaxy disk reveal a region with reduced flux around the center of the galaxy and a horse shoe shaped region with enhanced flux in the outer disk. The characterization of the ionization regions based on emission line diagnostic diagrams shows that the region of reduced flux seen in the ultraviolet is within the AGN-dominated area. The CO J$_{2-1}$ map of the galaxy disk reveals a cavity in the central region. The image of the galaxy disk at redder wavelengths (9050-9250 \overset{\lower.5em\circ}{\mathrm{A}}) reveals the presence of a stellar bar. The star formation rate map of the galaxy disk shows that the star formation suppression in the cavity occurred in the last few 10$^8$ yr. We present several lines of evidence supporting the scenario that suppression of star formation in the central region of the disk is most likely due to the feedback from the AGN. The observations reported here make JO201 a unique case of AGN feedback and environmental effects suppressing star formation in a spiral galaxy.Comment: Author's accepted manuscrip

Exact bounds on the ground-state energy of the infinite-U Hubbard model

We give upper and lower bounds for the ground-state energy of the infinite-U Hubbard model. In two dimensions, using these bounds we are able to rule out the possibility of phase separation between the undoped-insulating state and an hole-rich state.Comment: 2 pages, 1 figure, to appear in Phys. Rev.

Natural history of therapeutic management in oral cancer

The natural history of a diseases is greatly influenced by the course of therapeutic management. Just after the tissue stage of the disease is aver. The cure rate of diseases, particularly those of cancers, could probably be modified to a greater extent, if the natural history of the therapeutic manage­ment is understood properly, so that the community education programme be organised in the proper direction, to trigger early diagnosis. Home remedy urn the first preference of 76.8% of oral cancer cases, 64.6% preferred traditional unqualified practitioners as their 2nd preference of place of treatment for oral cancer. Thus during the stage of fa stigium a case oj oral cancer gets frustrated with the hospital treatment and awaits death counting his day

Gall Bladder And Common Bile Duct Stones – When Is Direct Cholangiography Indicated?

The medical records of 277 consecutive patients who underwent cholecystectomy for benign gall stone disease, were reviewed to determine the incidence and cause of biliary tract obstructuion