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91.
Mukherjee S Bauri AK Bhattacharya S 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,79(5):1952-1958
The present paper reports the synthesis of a designed bisporphyrin (1), and its supramolecular complexes with C60, C70 and their derivatives, namely, tert-butyl-(1,2-methanofullerene)-61-carboxylate (2) and [6,6]-phenyl C70 butyric acid methyl ester (3) in toluene medium. C60, C70 and their derivatives undergo ground state non-covalent interaction with 1 is evidenced from absorption spectrophotometric study in which it is observed that the intensity of the Soret absorption band of 1 decreases considerably in presence of C60, C70 and their derivatives. Steady state fluorescence studies reveal efficient quenching of fluorescence of 1 in presence of fullerenes. The binding constant (K) values of the fullerene/1 complexes follows the trend: 2/1相似文献
92.
Karakoti AS Das S Thevuthasan S Seal S 《Angewandte Chemie (International ed. in English)》2011,50(9):1980-1994
Application of inorganic nanoparticles in diagnosis and therapy has become a critical component in the targeted treatment of diseases. The surface modification of inorganic oxides is important for providing diversity in size, shape, solubility, long-term stability, and attachment of selective functional groups. This Minireview describes the role of polyethylene glycol (PEG) in the surface modification of oxides and focuses on their biomedical applications. Such a PEGylation of surfaces provides "stealth" characteristics to nanomaterials otherwise identified as foreign materials by human body. The role of PEG as structure-directing agent in synthesis of oxides is also presented. 相似文献
93.
Pardasani D Tak V Purohit AK Kanaujia PK Dubey DK 《European journal of mass spectrometry (Chichester, England)》2011,17(1):57-64
Gas chromatography-mass spectrometry (GC-MS) analysis of O,O'-dialkyl methylphosphonites (DAMPs) was carried out with a view to developing a database and understanding the mechanism of fragmentation. DAMPs are included in the list of schedule 2B4 chemicals of the Chemical Weapons Convention. GC-MS analysis of DAMPs and their deuterated analogs revealed that their fragmentations were dominated by α-cleavages, alkenyl radical loss and hydrogen rearrangements. Based on fragment ions of deuterated analogs and density functional theory calculations, the fragmentation routes were rationalized. 相似文献
94.
In the following article, we consider approximate Bayesian computation (ABC) inference. We introduce a method for numerically approximating ABC posteriors using the multilevel Monte Carlo (MLMC). A sequential Monte Carlo version of the approach is developed and it is shown under some assumptions that for a given level of mean square error, this method for ABC has a lower cost than i.i.d. sampling from the most accurate ABC approximation. Several numerical examples are given. 相似文献
95.
Super crystallization of ligand‐capped nanocrystals into defined periodic solids from solution is the definitive demonstration of their self‐organizing properties. To date, this has been mainly limited to spherical nanocrystals where organization emulates atom or molecule packing in regular crystals with the most thermodynamically stable arrangement being eventually preferred. Here, the crystallization of wurtzite CdS nanorods into micrometer‐sized CdS superstructures with regular hexagonal symmetry is demonstrated by fine‐tuning the nanorod dispersibility over time. It is shown that the supercrystals have a long nucleation stage to form monolayer hexagons followed by a relatively faster growth stage both occurring rod by rod (in‐plane) and layer by layer (out of plane). The perfectly symmetrical hexagon shape of the final structure is mapped from the wurtzite crystal structure of each individual nanorod where they pack in side by side and end to end arrangements. These well‐defined superstructures are highly attractive for applications that collectively exploit electronic or optical properties that are synthetically tunable through the size and shape of each nanorod building block. 相似文献
96.
Drevogenin B is shown to be 11-O-acetyl-drevogenin P. The earlier derived structure for drevogenin A (11-O-acetyl-drevogenin P) is further confirmed by conversion of 3-O-acetyl-drevogenin A. 相似文献
97.
98.
Mathematische Annalen - 相似文献
99.
100.
P. G. Adyalkar V. V. Rane V. V. S. Mani J. P. Dias 《Proceedings Mathematical Sciences》1975,81(3):108-117
The paper attempts to evaluate the permeability data obtained from 75 aquifer performance tests conducted on open wells tapping the water table aquifer of the basaltic lava flows spread over the three different basins of Maharashtra. The permeability has been computed by Thiem’s formula and the modified Theis non-equilibrium formula. The statistical analysis of the permeability data of the study basins,viz., Bhima, Godavari and Wardha, reveal a decrease in permeability range as one proceeds from the Bhima basin (low rainfall area) through the Godavari basin (assured rainfall area) to the high rainfall area of Wardha basin. The permeability frequency graphs of the three study basins reveal different hydrogeological characteristics for each. 相似文献