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81.
Electronic charge density distribution in molecular systems has been described in terms of the topological properties. After briefly reviewing methods of obtaining charge densities from X-ray diffraction and theory, typical case studies are discussed. These studies include rings and cage systems, hydrogen bonded solids, polymorphic solids and molecular NLO materials. It is shown how combined experimental and theoretical investigations of charge densities in molecular crystals can provide useful insights into electronic structure and reactivity. 相似文献
82.
AbstractGraphene is emerged as a highly sought after reinforcing filler for epoxy matrix in view of its superior electrical, mechanical and thermal properties. Dispersion of low concentration of graphene can significantly enhance the epoxy/graphene nanocomposites properties. Dispersion of graphene in epoxy matrix depends on processing protocols used, and interfacial interaction between epoxy matrix and graphene. Interfacial interaction between epoxy matrix and graphene can be achieved by covalent and non-covalent modification of graphene. This paper comprehensively review the influence of different processing protocols adopted for the processing of epoxy/graphene nanocomposites, and its effect on mechanical, thermal and electrical properties. In addition, covalent and non-covalent strategies adopted for modification of graphene, and its influence on mechanical, thermal and electrical properties of epoxy/graphene nanocomposites are extensively discussed. The future challenges associated with graphene reinforced epoxy nanocomposites processing have been discussed. 相似文献
83.
In this paper, we examine a joint lot-sizing and process investment problem with random yield and backorders. We allow for inspection and develop stochastic models which provide the optimal inspection and lot-sizing policy as well as the optimal process investment for variance reduction. The process quality loss profile around the target is captured via a modification of the Reflected Normal loss function. We conduct numerical experiments assuming that the proportion of defectives follows a Uniform distribution while the process quality characteristic follows either a Normal or Uniform distribution. We also develop closed-form solutions that depend on at most the first two moments of any general probability distribution of defective units and which allow us to examine the nature of optimal policies. We demonstrate via numerical experiments the value of our integrated approach for jointly determining optimal inventory, inspection, and investment policies. Overall, our models and analyses provide some interesting insights into this reasonably complex inventory-quality problem and open up several avenues for future work in this area. 相似文献
84.
Babasaheb P. Bandgar Sangita S. Makone Sulakshana R. Kulkarni 《Monatshefte für Chemie / Chemical Monthly》2000,131(4):417-420
Summary. A simple, efficient, and environmentally friendly synthesis of geminal diacetates using Envirocat EPZ10? under microwave activation and solvent-free conditions is described. Easy separation and recyclability of the catalyst, high
reaction rates, high yields, and easy work-up are important advantages of this method.
Received November 3, 1999. Accepted November 24, 1999 相似文献
85.
The relationship between the harmonicity and analyticity of a continuous map from the open unit disc to the underlying space
of a real algebra is investigated. 相似文献
86.
P. K. Khanna Deepti Kulkarni Rupinder K. Beri 《Journal of nanoparticle research》2008,10(6):1059-1062
Reduction of silver myristate (AgMy) under mild thermal reaction conditions in a dipolar aprotic solvent i.e. N, N-dimethylformamide (DMF) has been carried out. UV–visible absorption measurements of dried and re-dispersible brown flocculants
showed broad features of surface plasmon resonance (SPR) due to silver nanoparticles. The freshly isolated particles showed
absorption bands at 414 and 485 nm, respectively, due to inter-particle coupling or clustering of silver ions and silver atoms.
X-ray diffraction (XRD) pattern of fcc zero-valent silver resulted in crystallite size of about 10 nm. Scanning electron microscopy
(SEM) revealed formation of rod shaped silver with increasing reaction temperature. Thermal analysis (TGA) showed about 10%
weight loss due to organic capping. 相似文献
87.
Srinivasa Budagumpi M. P. Sathisha Naveen V. Kulkarni Gurunath S. Kurdekar Vidyanand K. Revankar 《Journal of inclusion phenomena and macrocyclic chemistry》2010,66(3-4):327-333
A series of new 24-membered macrocyclic CoII, NiII, CuII and ZnII complexes of the ligands L1H2 and L2H2 were prepared by the non-template and template methods respectively. The ligand L1H2 was formed by the condensation of pyrazole-3,5-dicarbohydrazide and glyoxal and all attempts to isolate the ligand L2H2 were unsuccessful. These, ligand and transition metal complexes were characterized on the basis of elemental analysis, IR, 1HNMR, UV–Visible, magnetic susceptibility measurements, ESR, conductivity measurements, FAB-mass and thermal analysis. The redox behavior of metal ions in the polyazamacrocyclic ligand field is also studied. Electroreduction of carbon dioxide to carbon monoxide is mainly focused on using polydentate azamacrocyclic ligands with amine and imine functionalities, based on the electrochemical behavior of nickel (II) ion in the macrocyclic territory. 相似文献
88.
Kulkarni NV Budagumpi S Kurdekar GS Revankar VK Didagi S 《Chemical & pharmaceutical bulletin》2010,58(12):1569-1575
A novel Cu(II) and Zn(II) complexes of triazolo-quinoline derivatives were synthesized by in situ method and were characterized by the spectro-analytical methods and their pharmacological properties were evaluated. The compound C3 has exhibited promising anticonvulsant activity towards the electroshock induced seizures in Wistar rats and possesses low toxicity, providing a high safety profile. 相似文献
89.
This paper reports on the spectral (response) characteristics of fiber Bragg grating sensor to various methanol concentrations. A complete experimental analysis on the use of Ge-B co-doped fiber Bragg grating sensor for a concentration and refractive index measurement is presented. The spectral changes in the grating response due to variation of concentration have been investigated in relation to new sensing configurations. The results also highlight the possibilities of using the sensor for medical and biological applications. 相似文献
90.
M.?Prabu S.?SelvasekarapandianEmail author A.?R.?Kulkarni S.?Karthikeyan G.?Hirankumar C.?Sanjeeviraja 《Ionics》2011,17(3):201-207
Olivine-structured pure LiNiPO4 and yttrium-doped LiNiPO4 have been synthesized by a Pechini-type polymerizable precursor method. Compound formation temperature is confirmed from
thermogravimetry to differential thermal analysis. Powder X-ray diffraction pattern confirmed the formation of phase pure
LiNiPO4 compound with an orthorhombic structure with fine crystallite size. Presence of preferred local cation environment is understood
from Fourier transform infrared spectroscopy (FTIR) studies. XRD and FTIR studies show that doped yttrium ion entered in the
lattice of LiNiPO4. It has been found that the ionic conductivity of LiNiPO4 is enhanced by around two orders of magnitude by doping yttrium. Dielectric spectra show the decrease in dielectric constant
with increase in frequency. Dielectric loss spectra reveal that dc conduction contribution predominates in the sample. 相似文献