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21.
Glycine phosphite (NH3CH2COO.H3PO3), a potential ferroelectric material, was grown as single crystals from aqueous solutions by slow evaporation and slow cooling methods. Laboratory synthesized title compound was purified by recrystallization method and confirmed by Fourier transform infrared and Laser Raman studies. Temperature dependent solubility in double distilled water in the range between 288 and 328 K was determined by gravimetric method. Morphological importance of various growth faces were studied by optical goniometry. Powder x‐ray diffraction study performed on the grown crystals confirms the crystal system and lattice parameters of the unit cell. Optical transparency of the grown crystals in the ultraviolet–visible ‐near infrared region was studied by spectroscopic method. Thermal stability of the grown crystals in the temperature region above ambient until melting was studied using differential scanning calorimetry. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
22.
Alterations in Zn2+ concentration are seen in normal tissues and in disease states, and for this reason imaging of Zn2+ is an area of active investigation. Herein, enriched [1-13C]cysteine and [1-13C2]iminodiacetic acid were developed as Zn2+-specific imaging probes using hyperpolarized 13C magnetic resonance spectroscopy. [1-13C]cysteine was used to accurately quantify Zn2+ in complex biological mixtures. These sensors can be employed to detect Zn2+ via imaging mechanisms including changes in 13C chemical shift, resonance linewidth, or T1.  相似文献   
23.
Journal of Thermal Analysis and Calorimetry - Nonlinear convective flow and heat transfer characteristics are analyzed between stationary nonporous and porous rotating disks utilizing graphene...  相似文献   
24.
Summary Weakly I -continuous functions were introduced and studied by A?ikg?z, Noiri and Yüksel [1]. We further extend their study, generalize some of their results and discuss its properties.  相似文献   
25.
(±)-Piperidine-2-carboxylic acid ((±)-pipecolic acid) has been resolved by the fractional crystallisation of diastereomeric palladium(II) complexes containing orthometallated (S)-(−)-1-[1-dimethylamino)ethyl]naphthalene. The enantiomers of the acid were liberated from the individual configurationally homogeneous diastereomers of the complex in high yield with []D ± 26.0 (c 1.00, H2O). The crystal and molecular structures of both diastereomers of the complex have been determined.  相似文献   
26.
1-Trifluoroacetyl-3-dialkylaminomethyl-5-monosubstituted benzimidazoline-2-thiones have been synthesized from p-substituted anilines which were acetylated with trifluoroacetic acid. The trifluoroacetanilides were nitrated, reduced and cyclised with carbon disulphide in the presence of alcoholic potassium hydroxide and finally treated with formaldehyde and suitable secondary amines to afford the Mannich bases. The compounds were characterised by their analytical and spectral (ir, pmr, 19F and mass) data. The synthesized compounds have been screened for anti-inflammatory and analgesic activity and found to be active.  相似文献   
27.
Thermogravimetric analysis (TGA) with nitrogen and oxygen as carrier gas is used for the analysis of cotton lint samples for evaluating their stickiness. The advantage of the low melting point of trehalulose, a commonly found sugar, in the presence of oxygen as carrier gas is used for the evaluation. The oxidation of sugar present in the cotton lint results in increased weight around the melting point, which is proportional to the sugar content. The decomposition of the sugar further results in weight loss. This method is compared with the sticky cotton thermodetector and viscosity method for the estimation of sugar content. Good agreement between the methods suggests the usefulness and simplicity of TGA for estimation of stickiness in cotton.  相似文献   
28.
Absorption and fluorescence emission spectra of coumarins 6 and 7 were recorded in solvents with different solvent parameters, viz., dielectric constant epsilon and refractive index n. The fluorescence lifetime of these dyes were measured in butanol at higher values of viscosity over temperature. Experimental ground and excited state dipole moments are determined by means of solvatochromic shift method and also the excited state dipole moments are determined in combination with ground state dipole moments. It was determined that dipole moments of the excited state were higher than those of the ground state in both the molecules.  相似文献   
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The electrohydrocyclization of tethered enone/enoate or bisenone systems which contain an alkoxyl substituent in the tether was studied. Rather surprisingly, the cyclization of these compounds afforded very different products depending upon the alkoxy substituent. This behavior and its potential applications will be discussed.  相似文献   
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