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891.
Kavita Jain 《合成通讯》2018,48(15):1966-1973
A simple and convenient method for the synthesis of fluorinated α-cyanoacetate derivatives has been developed by using electrophilic fluorination of allyl and benzyl substituted α-cyanoacetates with N-fluorobenzensulfonimide (NFSI) as electrophilic fluorinating agent via phase transfer catalysis. The reaction is transition metal free and carried out in aqueous and mild reaction conditions in the presence of readily available tetra-N-butylammonium iodide (TBAI) as phase-transfer catalyst.  相似文献   
892.
Jain  Rashi  Mujwar  Somdutt 《Structural chemistry》2020,31(6):2487-2499
Structural Chemistry - The outbreak of severe acute respiratory syndrome coronavirus-2 is causing a serious disaster through coronavirus disease-19 (COVID-19) around the globe. A large segment of...  相似文献   
893.
Journal of Solid State Electrochemistry - Xanthan gum (XG)-based hydrogels containing sodium hydroxide (NaOH) salt were synthesized with the use of distilled water (DW) at room temperature and...  相似文献   
894.
The process of formation of nanoparticles obtained by mixing two micellized, aqueous solutions has been simulated using the Monte Carlo technique. The model includes the phenomena of finite nucleation, growth via intermicellar exchange, and coagulation of nanoparticles after their formation. Using the model, an exploratory study has been conducted to analyze whether the coagulation of nanoparticles is the reason for the formation of nanoparticles whose sizes are comparable to the size of the reverse micelles. The model explains the possible mechanism of coagulation of semiconductor nanoparticles formed within reverse micelles and its effect on the evolution of their size with time. The model is predictive in nature, and the simulation results compare well with those observed experimentally.  相似文献   
895.
C-terminal dimerization of a tripeptide palindrome afforded fibrillation in solution through an assembly probably driven by hydrogen bonding and hydrophobic contributions; such an approach provides an expeditious entry into fabrication of fibrillating peptides from non-fibrillating peptide sequences.  相似文献   
896.
Y S Jain  B Singh  B N Khanna 《Pramana》1982,18(6):511-516
A relationship between the torsional frequency (v 10) and the potential barrier (V n) has been determined forAB n type molecular system havingn-fold symmetry axis. It is found thatv 10 varies prominently asV n 1/2 ,V n andV n 2 in certain ranges. TheV n value computed fromv 10 andI* r has been compared with that obtained from other experimental data for someAB n units in different molecular-crystalline systems. Although there is in general a good agreement, in some cases the values differ significantly, perhaps due to the erroneous assignment of torsional mode and/or the large errors in theV n value obtained from other experimental data.  相似文献   
897.
898.
B K Jain 《Pramana》1976,7(4):287-290
Total cross-section forπ +, using the high energy approximation, have been calculated for12C and32S at various energies around the (3, 3) resonance in the free pion-nucleon system. It is observed that the shift in energy of the position of the maximum in the pion-nucleus cross-section with respect to that in the free pion-nucleon system depends sensitively on the shape of the nuclear density. Using the realistic density it is further found that the shift due to the off-shell behaviour of the pion-nucleon scattering amplitude is very small. This observation is different from that reported in the literature by other authors.  相似文献   
899.
900.
N C Jain 《Pramana》1989,33(6):677-683
A new method which takes into account the separate matrix correction factors for bulk and surface has been tried out for quantitative Auger electron spectroscopy analysis of binary alloys. The calculations use an iteration scheme. It has been applied to the Fe-Cr alloys studied at this Centre and the Auger electron spectroscopy data for the other alloy systems available in literature. The results are now more compatible with the expectation that the surface composition is different from the bulk.  相似文献   
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