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91.
Salunkhe Nilesh G. Ladole Chandrashekhar A. Thakare Nikita V. Aswar Anand S. 《Research on Chemical Intermediates》2018,44(1):355-372
Research on Chemical Intermediates - We report the synthesis of sulfuric acid-functionalized silica-coated magnetic nanoparticles (MgFe2O4@SiO2–SO3H) as a catalyst for the microwave-assisted... 相似文献
92.
Paul Anand 《Annals of Operations Research》1990,23(1):91-101
A study is made of the use of axiomatic methods in theories of social phenomena. 相似文献
93.
Precipitates of ceria were synthesized by homogeneous precipitation method using cerium nitrate and hexamethylenetetramine
at 80°C. The precipitates were ground to fine particles of average size ∼0.7 μm. Circular disks with 10 mm diameter, 2 and
3 mm thickness were prepared from the green compacts by sintering at 1300° C for three different sintering times. Evolution
of the pore structures in these specimens with sintering time was investigated by small-angle neutron scattering (SANS). The
results show that the peak of the pore size distribution shifts towards the larger size with increasing sintering time although
the extent of porosity decreases. This indicates that finer pores are eliminated from the system at a faster rate than the
coarser ones as sintering proceeds and some of the finer pores coalesce to form bigger ones. 相似文献
94.
95.
Microdroplets of 15-μm diameter are subjected to ultra-short laser pulses of intensities up to 1015Wcm−2 to produce hot dense plasma. The hot electrons produced in the microdroplet plasma result in efficient generation of hard X-rays in the range 50–150keV at an irradiance as low as 8×1014Wcm−2. The X-ray source efficiency is estimated to be about 2 ×10−7%. A prepulse that is about 11ns ahead of the main pulse strongly influences the droplet plasma and the resulting X-ray emission. For a similar laser prepulse and intensity, no measurable hard X-ray emission is observed when the laser is focused on a solid target of similar composition and this indicates that liquid droplet targets are best suited for hard X-ray generation in laser–plasma interactions. 相似文献
96.
97.
Venkataramanarao G. Anand Simi K. Pushpan Sundararaman Venkatraman Tavarekere K. Chandrashekar 《Journal of Chemical Sciences》2003,115(5-6):711-720
Expanded porphyrins containing seven pyrrole/heterocyclic rings linked in a cyclic fashion are termed heptaphyrins. The number
ofπ-electrons in heptaphyrins depends on the number ofmeso carbon bridges used to link the heterocyclic rings, accordingly heptaphyrins with 28π-electrons and 30π-electrons are reported to date. Both condensation reactions of the appropriate precursors and acid-catalysed oxidative coupling
reactions have been utilized to synthesise the heptaphyrins. The 30π heptaphyrins exhibit rich structural diversity where some of the heterocyclic rings in the macrocycle undergo a 180° ring
flipping. An overview of the synthetic methods employed for the synthesis of heptaphyrins, their spectroscopic properties,
structural behaviour and aromatic properties are highlighted in this paper.
Dedicated to Professor C N R Rao on his 70th birthday 相似文献
98.
R. Ramanathan 《Journal of Computational and Applied Mathematics》2003,160(1-2):259-263
A covariant generalisation of Wigner function proposed by us some years ago is reviewed, and its remarkable and useful properties are elucidated; its being a natural solution to a relativistically covariant Liouville equation is also demonstrated. 相似文献
99.
Hang Wang Anand S. Badami Abhishek Roy James E. McGrath 《Journal of polymer science. Part A, Polymer chemistry》2007,45(2):284-294
Nanophase‐separated, hydrophilic–hydrophobic multiblock copolymers are promising proton‐exchange‐membrane materials because of their ability to form various morphological structures that enhance transport. A series of poly(2,5‐benzophenone)‐activated, telechelic aryl fluoride oligomers with different block molecular weights were successfully synthesized by the Ni(0)‐catalyzed coupling of 2,5‐dichlorobenzophenone and the end‐capping agent 4‐chloro‐4′‐fluorobenzophenone. These telechelic oligomers (hydrophobic) were then copolymerized with phenoxide‐terminated, disulfonated poly(arylene ether sulfone)s (hydrophilic) by nucleophilic, aromatic substitution to form hydrophilic–hydrophobic multiblock copolymers. High‐molecular‐weight multiblock copolymers with number‐average block lengths ranging from 3000 to 10,000 g/mol were successfully synthesized. Two separate glass‐transition temperatures were observed via differential scanning calorimetry in the transparent multiblock copolymer films when each block length was longer than 6000 g/mol. Tapping‐mode atomic force microscopy also showed clear nanophase separation between the hydrophilic and hydrophobic domains and the influence of the block length as it increased from 6000 to 10,000 g/mol. Transparent and creasable films were solvent‐cast and exhibited moderate proton conductivity and low water uptake. These copolymers are promising candidates for high‐temperature proton‐exchange membranes in fuel cells, which will be reported separately in part II of this series. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 284–294, 2007 相似文献
100.