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71.
Bohm and Pines' Hamiltonian and their dispersion relation have been extended up to second order to account for double plasmon oscillations in the X-ray emission spectra of solids. The effect of interaction between electrons and plasmons has also been taken into account in the dispersion relation. An expression for the relative intensity of low-energy double plasmon satellites has been derived. Fairly good agreement is obtained between values of the relative intensity calculated using this expression and values observed experimentally by Jenkins and Chung.  相似文献   
72.
An efficient and convenient synthesis of 5,10,15‐triarylcorroles by the condensation of aryl aldehydes with pyrrole catalyzed by Amberlyst 15 followed by oxidative cyclization with 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone (DDQ) at room temperature has been reported. Amberlyst 15 is more efficient catalyst under solvent free conditions and DDQ is more suitable oxidant in dichloromethane than those of other catalysts and oxidants, respectively, for the synthesis of corroles at room temperature.  相似文献   
73.
The reaction of metal complexes of the type [M(HL)Cl] or [M(HL)2] [where M = Cu(II), Ni(II), Mn(II), Co(II) and Zn(II) and H2L = N-benzoyldithiocarbazate] with an excess of ethylenediamine (en) in CHCl3–MeOH medium leads to ring closure by desulfurisation to yield unique mixed-ligand complexes 1–4, [Cu(en)2](pot)2(pot = 5-phenyl-1,3,4-oxadiazole-2-thiol), [M(en)2(pot)2] [M = Ni(II), Mn(II)] and [Zn(en)(pot)2]. The metal complexes have been characterized by various physicochemical methods. The molecular structure of [Cu(en)2](pot)2 has been determined by a single crystal X-ray diffraction study. In the centrosymmetric unit of [Cu(en)2](pot)2, the metal ion has a square planar arrangement of four symmetry related N-atoms of two en groups and is ionically bonded to two pot anions. Weak interaction studies on the complex reveal the presence of a hydrogen-bonded network in the molecule involving non-coordinating donor atoms of the pot anion with en resulting in the formation of an extended three-dimensional network. The arrangement of the [Cu(en)2]2+ units, at a dihedral angle of 49.43° to pot, provides a network of intermingled chains leading to a π–π stacked 3-dimensional framework.  相似文献   
74.
Cellulose - In an enzymatically driven lignocellulosic biorefinery, pretreatment and hydrolysis modules are the two most significant cost contributors for obtaining high gravity sugar solutions....  相似文献   
75.
Epoxidations of indene, styrene, 2-chlorostyrene, 3-chlorostyrene, 4-chlorostyrene, 4-bromostyrene, and naphthalene using Musa paradisiaca plant juice chloroperoxidase in the presence of H2O2 and t-butyl peroxide as oxidants have been studied. The steady-state kinetic parameters, Km and kcat of the enzyme for the above substrates have been determined. The temperature and pH optima of the epoxidation are 25°C and 6.2, respectively. The yield of styrene oxide in the presence of H2O2 was 44%. The results show that M. paradisiaca plant juice chloroperoxidase is a potential biocatalyst for organic epoxidation reactions.  相似文献   
76.
Three compounds ( 1 – 3 ) were synthesized, where ethynylferrocene is substituted at different positions of anthracene and anthraquinone, and their biological properties were investigated. Compounds 1 – 3 were characterized using NMR and mass spectroscopies and confirmed by their single‐crystal X‐ray structure. They were also characterized from electronic and photophysical properties. All three crystal structures were optimized using density functional theory calculations. The presence of C–H???π interactions in 1 – 3 leads to the formation of two‐ and three‐dimensional networks. The bioactivity of 1 – 3 was expressed by molecular docking with various cancerous proteins, which participated in progression of cancer. Compound 2 displayed the best interaction with cancer‐related Aurora A protein in terms of both binding energy (?10.61 kcal mol?1) as well as inhibition constant (16.74 nM). The molecular docking result also coincides with cytotoxicity on cancer cell lines (A375, HeLa) and DNA/protein binding affinity.  相似文献   
77.
Infrared intensity analysis of MXY2 type molecules has been attempted. The dipole momentμ of C=O is obtained to be different for different moleculesviz. for CH2O, 1.9052; for COCl2, 1.1517; for COF2, 0.6340; and for COBr2, 0.7687. Similarly in the case of CSF2 and CSCl2 μ C=S it was found to be 0.2473 and 0.2983 respectively. This shows that the effect of the electro-negative halogen atoms is very important. Presented at the ‘National Symposium on Molecular Spectroscopy’, Annamalai University, Annamalainagar on 28 February 1976.  相似文献   
78.
Summary The energy spectra of sea-level muons at different zenith angles have been estimated from the latest JACEE primary spectrum using ISR results modified for p-nucleus interactions. The theoretical results have been compared with the experimental results. Using the recent modified range-energy relation after Kobayakawa along with the fluctuation correction procedure after Kiraly, Kiraly and Osborne, the muon range spectra in deep underground at different polar angles have been calculated. The derived results are well in agreement with the latest Mont Blanc data after Bergamascoet al., Battistoniet al. and Utah experiments after Bergessonet al.
Riassunto Si stimano gli spettri d'energia muonica a livello del mare a differenti angoll zenitali dal piú recente spettro delle primarie JACEE usando risultati ISR modificati per interzioni p-nucleo. I risultati teorici sono stati confrontati con i risultati sperimentali. Usando la recente relazione modificata intervallo-energia di Kobayakawa oltre alla procedura di correzione delle fluttuazioni di Kiraly, Kiraly e Osborne sono stati calcolati gli spettri dell'intervallo muonico in profondità per differenti angolia polari. I risultati derivati sono in buon accordo con i dati piú recenti del Monte Bianco di Bergamascoet al., Battistoniet al. e gli esperimenti Utah di Bergessonet al.

Резюме Оцениваются энергетические спектры мюонов на уровне моря длл различных зенутных углов, исходя из последнего JACEE первичного спектра с использованием ISR-результатов, модифицированных для протон-ядерных взаим действий. Теоретические результаты сравниваются с экспериментальными данным Используя недавнее модифицированное соотношение между пробегом и энергиек Кобайакавы и методику Кирали, Кирали и Осборна для флуктуационных поправок вычисляются спектры пробегов мюонов под землей для различных полярных углов. Полученные резулятаты хорошо согласуются с последними данными под Мон-Бланом и с результатами Юта-экспериментов.
  相似文献   
79.
Summary A stack consisting of CR-39(DOP) detector with 2.6 cm Al target was exposed to a238U beam of energy 0.927 GeV/n from LBL BEVALAC to study the large-fragmentation phenomena during U+Al interaction. The diameter distribution of the etch pits formed in the plastic detectors for the first three projectile fragments of chargeZ F≥89 yields the partial cross-section data which is comparable to the data obtained from the cone length distribution. The present result on the partial cross-section is significantly higher than those expected from the abrasion-ablation model of Wilson, Townsed and Badavi (1987). The authors of this paper have agreed not to receive the proofs for correction.  相似文献   
80.
Raman and infrared intensity analysis of CHCl3 is attempted to determine the bond polarisability derivatives and bond dipole moments and their derivatives respectively, on lines expained in our earlier papers.  相似文献   
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