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. Moreover, during manufacturing and storage processes, degradation of phenytoin can generate benzophenone as a new compound. The possible impurities of phenytoin are shown in Figure 1 . With a short term exposure of benzophenone, it reportedly caused

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Abstract  

The solvent-free reduction of benzophenone and five substituted benzophenones with sodium borohydride to the corresponding alcohols was studied by thermal analysis, X-ray powder diffractometry, NMR spectroscopy, and scanning electron microscopy. In most cases, the reaction occurs via liquid eutectic phases that are formed between the benzophenone and the resulting benzohydrol. Nevertheless, this reaction can be carried out without the need for a solvent, leading to pure alcohol without side products. In some cases, heating may be necessary to achieve a reasonably short reaction time. In conclusion, this reaction type appears to be feasible as a preparative organic reaction that avoids a solvent.

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Abstract  

Benzophenone is a well-known material, which exhibits non-linear optical (NLO) property. It has been grown by solution technique adopting slow evaporation method from solvents CHCl3, CCl4 for the first time. Solubility metastable zone width and inductions periods of benzophenone in CHCl3 and CCl4 were determined. Interfacial tension values at two different temperatures for various super saturations, such as 1.10, 1.15, 1.20 and 1.25 were determined using induction period. From interfacial tension values, the nucleation parameters, such as the radius of the critical nuclei (r*), the free energy change for the formation of a critical nucleus (ΔG*) and the number of molecules in the critical nucleus were also calculated for benzophenone in CHCl3 and CCl4 at two different temperature. The effect of surface tension, viscosity, density of these solvents are correlated with interfacial tension. The metastable zone width is also correlated with interfacial tension. The solution grown crystals were carefully harvested and subjected to various characterization studies to check its purity and to determine its applicability.

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Abstract  

Good quality benzophenone (BP) crystals were grown by solution technique using CHCl3 as solvent by adopting slow evaporation method at room temperature. The grown crystals were subjected to various characterization studies to analyze its purity and applications. The condensation product 2,4-dinitro phenyl hydrazone of benzophenone (DNPBP) was prepared by adopting standard procedure. Then mixed crystal of BP and DNPBP was also grown by solution growth. Both the condensation product and mixed crystals were characterized by UV, FTIR, 1H NMR spectra. Thermal (TG and DTA) studies have proved to be very useful techniques not only to study the thermal properties of BP, DNPBP and mixed crystal but also to study their purity. Second harmonic generation (SHG) efficiency of the grown crystals was determined.

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Summary  

The preparation of a solid phase extractant (SPE), dicyclohexano-18-crown-6 embedded benzophenone, for preconcentration of uranium(VI) is described. The uranium(VI) can be quantitatively retained from 0.5 l solution on 1% dicyclohexano-18-crown-6 embedded benzophenone in the pH range 6.0-7.0, and then eluted with 5.0 ml of 1M HCl. Uranium(VI) content of the eluent was determined spectrophotometrically by Arsenazo III. Calibration graphs are rectilinear over the uranium(VI) concentration in the range of 0.004-0.4mg.ml-1. Five replicate determinations of 40mg of uranium(VI) present in 0.5 l sample gave a mean absorbance of 0.185 with a relative standard deviation of 2.45%. The detection limit corresponding to three times the standard deviation of the blank was found to be 2.0mg.l-1. The accuracy of the developed preconcentration procedure was tested by analyzing standard marine sediment reference material. The uranyl ion content of soils and sediments was estimated spectrophotometrically after the preconcentration procedure and compared to the results gained by standard inductively coupled plasma mass spectrometry (ICP-MS).

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Abstract  

In this study, the entrapment of benzophenone (BZ) into supramolecular nanoassemblies prepared by mixing two water-soluble associative polymers (i.e. polymerized β-CD (pβ–CD) and dextran grafted with lauryl-side chains (MD)) has been investigated by using isothermal titration microcalorimetry (ITC) and molecular modeling. ITC experiments have been performed at various temperatures (4 °C (277 K), 25 °C (298 K), and 37 °C (310 K)) to evaluate the interaction of BZ with pβ–CD in comparison with β-CD. The inclusion complexation for both β-CD/BZ and pβ–CD/BZ interactions was entropy-driven (|ΔH| < |TΔS|) when the temperature of the experiment was low (4 °C) and enthalpy-driven (|ΔH| > |TΔS|) with minor entropic contribution when the temperature was increased (25 and 37 °C). Using all the thermodynamic data obtained for β-CD/BZ and pβ–CD/BZ interactions when the temperature of the experiment was varied, the
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plot was perfectly linear, which reflected an enthalpy–entropy compensation process. Finally, the combination of ITC data with molecular modeling provided consistent information in regard to the location of MD side chains and BZ inside the cyclodextrin cavity, as well as concerning the stability of the nanoassemblies loaded with BZ.
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bisphenol-A (DGEBA, Grade LY556 having EEW 177) was procured from Hindustan Ciba Geigy Ltd. 1,3-Bis(3-glycidyloxypropyl)tetramethyl disiloxane (BGPTMSO, EEW180), 3,3’,4,4’-benzophenone tetracarboxylic dianhydride (BTDA), 1,4-phenylene diamine (PD), 1

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oxidation [ 1 ]. In this context, the selective partial oxidation of diphenylmethane (DPM) to benzophenone (BP) is a versatile route for the synthesis of many fine chemicals. BP is widely used as a constituent of synthetic perfumes and as a starting material

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Abstract  

Thermal behaviour of blends based on N,N'-bis(4-itaconimidophenyl) ether (IE) and 4,4'-bis(4-allyl-2-methoxyphenoxy) benzophenone (R1) or 4,4'-bis(2-allylphenoxy) benzophenone (R2) are described in this paper. The reactive diluent content was varied from 5-50% (mass/mass) in these blends. A decrease in the melting point and exothermic peak temperature was observed with increasing mass percent of reactive diluent. Thermal stability of blends was affected at high mass percentage of reactive diluents.

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