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61.
Harish Rajak Chinmay K.Behera Raiesh S.Pawar Pradeep K.Singour Murli Dhar Kharya 《中国化学快报》2010,21(10):1149-1152
<正>In pursuit for better antiepileptic drug and the importance of semicarbazones and 2,5-disubstituted 1,3,4-thiadiazoles as anticonvulsant pharmacophore,a series of novel N-({5-[(6-methyl-1-benzofuran-3-y1)methyl]-1,3,4-thiadiazol-2-yl}carbamothioyl) -2/3/4-substitutedbenzamide were designed,synthesized and evaluated for their anticonvulsant activity.The findings of the present studies confirmed that the pharmacophore model with four binding sites is crucial for anticonvulsant activity. Structure-activity relationships among synthesized compounds were also established. 相似文献
62.
Harish Krishnan 《Operations Research Letters》2010,38(5):436-440
Demand functions with “additive” and “multiplicative” uncertainty can fail to satisfy the “Slutsky symmetry” conditions required for demand to be based on utility maximization. This makes welfare analysis infeasible, which is important in many applications. Additive uncertainty can also generate negative demand realizations, and this can create non-trivial analytical problems. 相似文献
63.
Biswanath Das Yallamalla Srinivas Harish Holla Keetha Laxminarayana Ravirala Narender 《Tetrahedron letters》2007,48(38):6681-6683
Polymethylhydrosiloxane (PMHS) in combination with (bromodimethyl)sulfonium bromide or NBS has been utilized for the first time for reductive bromination of aromatic aldehydes at room temperature to afford the corresponding benzyl bromides in excellent yields. 相似文献
64.
Madan Mohan Shri G. Mittal Harish C. Khera Anant K. Sirivastava 《Monatshefte für Chemie / Chemical Monthly》1980,111(1):63-79
Complexes of pyridine-2-aldoxime (Hpox) with iron(II) and chromium(III) of type, [Fe(Hpox)2
X
2] (X=Cl, Br, I or NCS); [Cr(Hpox)3]Cl3·3 H2O; [Cr(Hpox)2
X
2]ClO4 (X=F, Cl or Br) and [Cr(Hpox)2(H2O)2]Br3·H2O were prepared and characterized by analytical X-ray powder diffraction, magnetism, vibrational (conventional and far-infrared) and electronic spectroscopy techniques. X-ray and electronic spectral data indicate that all the complexes except [Cr(Hpox)3]Cl3·3 H2O havetrans-pseudo-octahedral microsymmetry around the metal ion. Infrared spectral data indicate that the ligand, Hpox, behaves like a neutral ligand and coordinates to the metal ion through pyridine nitrogen atom and oxime nitrogen atom in all these complexes. The magnetic susceptibilities of chromium(III) complexes, measured over a temperature range 300–78 K, are independent of temperature whereas the magnetic moments of iron(II) complexes over a temperature range 300–20 K are dependent of temperature. The observed temperature dependence of magnetic moments of iron(II) complexes was used to evaluate the magnitude of orbital reduction factor,k, the low-symmetry distortion parameter, , and the extent of reduction in spin-orbital coupling, . In all these iron(II) complexes the magnetic results indicate the presence of an orbitally non-degenerate,5B2g, ground state. Magnetically unperturbed and perturbedMössbauer spectra of iron(II) complexes at various temperatures have also been reported. Magnetically perturbedMössbauer spectra of iron(II) complexes at 4.2 K in an axial field of 60kGauss indicate that the principal component of electric field gradient tensor is positive and consistent with5B2g ground electronic state in a tetragonal (D
4h) local site symmetry.
Übergangsmetallkomplexe mit Oxim-enthaltenden Liganden, VII. Elektronische und strukturelle Eigenschaften vonFe(II)-undCr(III)-Komplexen mit Pyridin-2-aldoxim
Zusammenfassung Es wurden Komplexe von Pyridin-2-aldoxim (Hpox) mit Fe(II) und Cr(III) vom Typ [Fe(Hpox)2 X 2] (X=Cl, Br, I, NCS), [Cr(Hpox)3]Cl3·3 H2O, [Cr(Hpox)2 X 2]ClO4 (X=F, Cl, Br) und [Cr(Hpox)2(H2O)2]Br3·H2O hergestellt. Charakterisierung und Diskussion von Geometrie und Bindungsverhalten in den Komplexen erfolgte auf Grund von analytischen Daten, Röntgen-Pulveraufnahmen, Elektronenanregungsspektroskopie, Infrarotspektroskopie, magnetischen Messungen undMössbauer-Spektroskopie.相似文献
65.
A new ion-selective electrode (ISE) based on dicyclohexano-18-crown-6 (DC18C6) as a neutral carrier is developed for lanthanum(III) ions. The electrode comprises of dicyclohexano-18-crown-6 (6%), PVC (33%), and ortho-nitrophenyl octyl ether (o-NPOE) (61%). The electrode shows a linear dynamic response in the concentration range of 10−6 to 10−1 M with a Nernstian slope of 19 mV per decade and a detection limit as 5×10−7 M. It has a response time of <30 s and can be used for at least 5 months without any significant divergence in potentials. The selectivity coefficients for mono-, di-, and trivalent cations indicate good selectivity for La(III) ions over a large number of interfering cations. The sensor has been used as an indicator electrode in the potentiometric titrations of La(III) with EDTA. The membrane is successfully applied in partially non-aqueous medium. It can be used in the pH range 4-9. 相似文献
66.
JPC – Journal of Planar Chromatography – Modern TLC - The phytochemical fingerprint profile of ammoniacum gum (from Dorema ammoniacum) was defined by subjecting different extracts of... 相似文献
67.
The growth of E1′ centers in a variety of natural and synthetic quartz crystals has been investigated by employing the electron spin resonance technique. It has been reported that the growth of E1′ centers, formed by irradiation and subsequent annealing at 300 °C for 15 min, scale with the concentration of the aluminum hole center, [AlO4]0, till a limit. Later, the E1′ centers show saturation even when the [AlO4]0-center continues to grow. For quartz with low efficiency of the formation of [AlO4]0-center or irradiated with low accumulated doses, the intensity of E1′ center was small where not all oxygen vacancies are converted to the E1′ center. Thus, besides the availability of a number of oxygen vacancy sites, the number of holes released from the [AlO4]0-center plays an important role in the formation of E1′ centers in quartz. 相似文献
68.
We study a single store multi-product inventory problem in which product sales are a composite function of shelf space. Since sales tend to deplete the amount of product on display, the effective shelf space assigned to the product diminishes with time unless replenishment occurs. We consider the problem of optimal replenishment times under these conditions. We assume a linear dependence of sales rate to effective shelf space in all our analysis. We present exact and approximate solutions for the single product and multi-product cases. For the single product case, we study the effect of space elasticity, cross elasticity and empty space elasticity on the optimal replenishment period. For the multi-product case we present a computationally attractive method using matrix exponentials and develop error bounds for this method. 相似文献
69.
Amita Verma N. Karar A. K. Bakhshi Harish Chander S. M. Shivaprasad S. A. Agnihotry 《Journal of nanoparticle research》2007,9(2):317-322
Homogenous nano structured CeO2 films have been prepared by a sol-gel process using different mole ratios of citric acid as additive. XPS studies clearly
illustrate an increase in Ce3+ proportion upon the use of higher citric acid content for the deposition of films. The crystallite sizes in the films lie
in the nanorange. Photoluminescence emission in the films is attributed to various defects resulting from crystallization.
Lowest transparency, high Ce3+ content and optimum sized crystallites in CeO2 (1:1.5) films have led to its highest PL characteristics. Ce3+ chemical state is the major contributor to the PL activity of these films. The SEM micrographs show a reduced level of CeO2 agglomeration in the films deposited using higher citric acid contents. A comparison of different properties of CeO2 films deposited using citric acid and CeO2–TiO2 films has also been made.
相似文献
70.
Biswanath Das Harish Holla Katta Venkateswarlu Anjoy Majhi 《Tetrahedron letters》2005,46(51):8895-8897
Treatment of Baylis-Hillman adducts with iodosobenzene (PhIO) in the presence of a catalytic amount of KBr in water at room temperature afforded the corresponding acyloxiranes in good yields. 相似文献