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81.
Raghu N. Prasad Devendra S. Parihar 《Monatshefte für Chemie / Chemical Monthly》1991,122(8-9):683-689
Summary Cadmium(II) complexes of the type [CdL] (NO3)2 (whereL = tetraazamacrocycle with a 12 to 32-membered ring) have been synthesized by the reactions of 2,3-butanedione or benzil with different aliphatic diamines viz. ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,6-diaminohexane, 1,8-diaminooctane and 1,12-diaminododecane in the presence of Cd(II) as template. These complexes have been characterized by elemental analyses, conductivity measurements and IR and NMR spectral studies.
Komplexe einer neuen Serie von -Diimin-Macrocyclen, 1. Mitt.: Synthese von Cadmium(II)-Komplexen von Tetraazamacrocyclen aus 2,3-Butandion oder Benzil
Zusammenfassung Es wurden Cadmium(II)-Komplexe des Typs [CdL] (NO3)2 (wobeiL einen 12-bis 32-gliedrigen Tetraazamacrocyclus darstellt) mittels der Reaktion von 2,3-Butandion oder Benzil mit verschiedenen aliphatischen Diaminen (Ethylendiamin, 1,3-Diaminopropan, 1,4-Diaminobutan, 1,6-Diaminohexan, 1,8-Diaminooctan und 1,12-Diaminododecan) hergestellt. Die Komplexe wurden mittels Elementaranalyse, Leitfähigkeitsmessungen und Infrarot- bzw. Kernresonanzspektroskopie charakterisiert.相似文献
82.
Dinesh Kumar Ashu Rani D. S. N. Prasad K. S. Gupta 《Reaction Kinetics and Catalysis Letters》1991,43(1):133-141
The kinetics of the oxidation of 2-furancarboxaldehyde by thallic perchlorate at 50°C obeys the rate law
相似文献
83.
Mahendra Madegowda Doreswamy Beeranahally H. Sridhar Mandayam A. Prasad Javaregowda S. Khanum Shaukath A. Shashikanth Sheena Sudha Belagur S. 《Structural chemistry》2004,15(3):211-214
Benzophenone analog 3 has been synthesized and characterized by the X-ray diffraction (XRD) method. The compound crystallizes in a monoclinic space group P21/c with cell parameters a = 7.701(8) Å, b = 7.151(5) Å, c= 28.323(3) Å, = 104.639(4)°, Z = 4. The structure exhibits intra- and intermolecular hydrogen bonding of the type N–HO, C–HO, and N–HN. The molecules are interlinked through hydrogen bonds forming an infinite chain. This polymeric-like structure may play an important role in biological activity. 相似文献
84.
Ryzhov V Bundy JL Fenselau C Taranenko N Doroshenko V Prasad CR 《Rapid communications in mass spectrometry : RCM》2000,14(18):1701-1706
The performance of infrared (2.94 microm) and ultraviolet (337 nm) lasers were compared for analysis of purified spores of B. subtilis, B. cereus and B. globigii on a four-inch end-cap reflectron time-of-flight instrument. Infrared matrix-assisted laser desorption/ionization (IR-MALDI) mass spectra of these microorganisms displayed a larger number of biomarker peaks above m/z 4000, compared with UV-MALDI. Biomarker peaks were observed at higher m/z values with the IR laser. 相似文献
85.
We present a novel sensing scheme for detecting the effects of unburned fossil fuels by integrating microarray technology and dielectrophoresis to develop single-neuron arrays. These arrays have the capability to sense and identify the two fuels, at parts per billion (ppb) concentrations, as well to determine the associated physiological changes at the single-cell level. Identification is achieved through frequency domain analysis of the measured changes to the extracellular electrical activity due to the effect of the fossil fuels. This yields unique electrical identifiers known as "signature patterns". Simultaneous optical visualization to the physiological changes is obtained by specific fluorescent staining. The correlation between the signature patterns and the cellular biological behavior establishes the veracity of this identification technique. 相似文献
86.
A quantitative, computer processed spectroscopic study, using photon counting, on the first excited triplet and singlet states of dilute isotopic mixed crystals of naphthalene at 2 K is presented for C10H8; 1-DC10H7; 2-DC10H7; 1,4-D2C10H6; 1,4,5-D3C10H5; 1,4,5,8-D4C10H4; 1,2,4,5,8-D5C10H3; a β-D4C10H4 and a β2-D6C10H2 as guests in C10D8 host crystals (and, for comparison, also for the same guests in a durene host crystal). The guest—host relative polarization Rashba formula has been verified quantitatively, and, as an added bonus, the elusive polarization ratio of the pure naphthalene crystal singlet Davydov components has been found to be 80 ± 20 (b/a), which is in poor agreement with the transition octupole—transition octupole model. The experimental guest energies and their concomitant quasiresonance shifts for bound singlet states (as well as the occurrences of unbound states) are in excellent quantitative agreement (about 1 cm?1) with those calculated using a Green's function formalism based on the ideal mixed crystal approximation and on a restricted Frenkel type dispersion relation derived from resonance pairs. The same Green's function also accounts quantitatively (within 10%) for the guest singlet state exciton localizations (guest excitation amplitudes). The triplet exciton state reveals an orientational site splitting (about 0.7 cm?1) for the 0—0 transition of the I-DC10H7 guest in C10D8 host. The order of the α and β substituted deuteronaphthalenes in the triplet state is reversed from that of the singlet state. The last two observations are related to the different nature of the lowest Π-Π* singlet and triplet states of naphthalene. 相似文献
87.
Transparent glasses of various compositions in the system (100−x)Li2B4O7−x(SrO-Bi2O3-Nb2O5) (where x=10, 20, 30, 40, 50 and 60, in molar ratio) were fabricated via splat quenching technique. The glassy nature of the as-quenched samples was established by differential thermal analyses. X-ray powder diffraction (XRD) and transmission electron microscopic studies confirmed the amorphous nature of the as-quenched and crystallinity in the heat-treated samples. Fluorite phase formation prior to the perovskite SrBi2Nb2O9 phase was analyzed by both the XRD and high-resolution transmission electron microscopy. Dielectric and the optical properties (transmission, optical band gap and Urbach energy) of these samples have been found to be compositional dependent. Refractive index was measured and compared with the values predicted by Wemple-Didomemenico and Gladstone-Dale relations. The glass nanocomposites comprising nanometer-sized crystallites of fluorite phase were found to be nonlinear optic active. 相似文献
88.
Prasad RL Prasad R Bhar GC Thakur SN 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2002,58(14):3093-3102
IR spectra in the 'Finger Print' spectral range has great importance in qualitative and quantitative analysis of explosives like trinitrotoluene (TNT) and cyclotrimethyltrinitramine (RDX). Highly resolved IR bands of these compounds have been recorded in the 9.6 and 10.6 microm regions of CO2 laser. TNT and RDX are large molecules each having 21 atoms and it is very difficult to assign the modes of vibrations by comparison with those in other molecules making the vibrational assignments of observed bands a difficult task. The ab initio quantum chemical calculation is used for determining the molecular geometries and modes of vibration of these molecules with a view to assign their normal modes in the high resolution vibrational photoacoustic spectra. These assignments are very reliable in view of the good agreement between the observed and calculated frequencies of deuterated TNT. 相似文献
89.
Synthesis and photochemistry of several title compounds 1-3 containing multiple chromophoric systems are described. The Diels-Alder reactions of 2,6,6-trimethylcyclohexa-2,4-dienone (5) with acetylenes 6a-d provided the adducts 7a-d, which upon hydrolysis furnished the desired bicyclo[2.2.2]octenediones 1a-d. Oximes 2a-d were prepared from diones 1a-d by treatment with hydroxylamine hydrochloride in pyridine. 5-Methylenebicyclo[2.2.2]oct-7-en-2-ones 3a-d were obtained via chemoselective Wittig reaction of the corresponding diones 1a-d. Bicyclo[2.2.2]octenediones 1a-c underwent chemoselective oxa-di-pi-methane rearrangement under sensitized conditions and suffered formal ketene extrusion upon direct irradiation. Direct irradiation of 1d afforded 11d via formal ketene extrusion but under sensitization it remained unchanged. Oximes 2a-d suffered ketene extrusion upon direct irradiation and E/Z isomerization under sensitized conditions. On the other hand, 5-methylenebicyclo[2.2.2]oct-7-en-2-ones 3a-d generally underwent 1,3-acyl shift. The plausible courses of all these photochemical processes are discussed. 相似文献
90.
Solvent water tapes in two hydrates of μ‐oxo‐bis[bis(2,2′‐bipyridine‐κ2N,N′)(sulfato‐κO)iron(III)]
O. O. E. Onawumi O. O. P. Faboya O. A. Odunola T. K. Prasad M. V. Rajasekharan 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(10):m480-m483
The title compound, [Fe2O(SO4)2(C10H8N2)4], crystallizes as two different hydrates, viz. 11H2O, (I), and 15H2O, (II). The complex is binuclear, in which the two FeIII atoms are coordinated in an octahedral geometry to four N atoms from the two bipyridine ligands, to one O atom from the sulfate ion and to an oxide ion on a twofold axis, which acts as a bridge between the symmetry‐related units. The Fe⋯Fe separation is 3.556 (4) Å and the Fe—O—Fe angle is 161.6 (2)° in (I); the corresponding values are 3.544 (1) Å and 165.8 (2)° in (II). In (II), one of the O atoms of the sulfate ion is disordered over two positions. In both compounds, the solvent water molecules form slightly different one‐dimensional hydrogen‐bonded networks which pass along the c axis of the unit cell. In (I), three solvent water molecules and, in (II), one solvent water molecule, are situated on the twofold axis. In both (I) and (II), the central O atom of the metal complex lies on a twofold axis. 相似文献
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