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121.
Bhatt PM Ravindra NV Banerjee R Desiraju GR 《Chemical communications (Cambridge, England)》2005,(8):1073-1075
Saccharin, acting as a weak acid, forms salts with basic APIs and these salts have the desirable property of enhanced water solubility. 相似文献
122.
123.
van Eis MJ van Der Linde BS de Kanter FJ de Wolf WH Bickelhaupt F 《The Journal of organic chemistry》2000,65(14):4348-4354
In contrast to the terminal phosphinidene complex PhPW(CO)(5) (2), which adds to [5]metacyclophane (1) in a 1,4-fashion, dichlorocarbene preferentially adds in a 1,2-fashion to the formal "anti-Bredt" type double bond of the aromatic ring of 1 to afford the norcaradiene 11b, which immediately rearranges to the bridged cycloheptatriene 12b and further by a [1,5] sigmatropic chlorine migration to the isomeric 13b as the first observable product. More slowly, the latter isomerizes via a dissociative mechanism to give 15b. A computational study supports the notion that the [1,5] chlorine migration in the rearrangement 12b --> 13b, for which an activation barrier of 70.2 kJ mol(-)(1) was calculated, is essentially concerted with minor charge separation. In contrast, the analogous [1,5] chlorine migration in the flat model compound 7,7-dichlorocycloheptatriene (12a) displays features of a dissociative pathway. 相似文献
124.
125.
A convenient method for the conversion of electron rich benzylic hydrocarbons to carbonyl compounds is reported. 相似文献
126.
The effective matrix elements in (d
3/2−f
7/2)2 configuration have been recently defined by Erskineet al. and Sherret al. assuming shell clcsures for S32 and Ca40. We have attempted to verify whether this empirically deduced (d
3/2−f
7/2)2 interaction permits thed
3/2 shell to remain closed when nucleons are added to Ca40. It is found that the Erskine interaction gives rise to ground states of thef
7/2 shell nuclei in which thed
3/2 orbit is completely filled. However that interaction over-binds Ca40. If the centroid of the (d
3/2)2 interaction is modified to fit the Ca40 binding energy, the ground states of Cr48 and Fe52 become deformed and thed
3/2 orbit is not completely filled. 相似文献
127.
The separation betweenT=0 andT=1 centroids of the empirical effective interaction is fairly large for the (d
3
2/−1
f
7/2)JT particle-hole interaction as compared to nearby (f
7/2)2
JT and (d
5/2)2
JT particle-particle interactions. This interesting feature of the empirical effective interaction is shown to arise as a consequence
of renormalization of the effective interaction as one truncates the configuration space from (s−d)−1(f−p)1 to (d
3
2/−1
f
7/2) and from (f−p)2 and (s−d)2 configurations to (f
7/2)2 and (d
5/2)2 respectively. 相似文献
128.
Shri Nivas Bhatt 《Rendiconti del Circolo Matematico di Palermo》1962,11(2):237-244
The author has established that if [λn] is a convex sequence such that the series Σn -1λn is convergent and the sequence {K n} satisfies the condition |K n|=O[log(n+1)]k(C, 1),k?0, whereK n denotes the (R, logn, 1) mean of the sequence {n log (n+1)a n}, then the series Σlog(n+1)1-kλn a n is summable |R, logn, 1|. The result obtained for the particular casek=0 generalises a previous result of the author [1]. 相似文献
129.
Shell model calculations for the nuclei91Mo,92Tc and93Ru in the Talmi approach have been done. The ground state binding energies and the excitation spectra agree with experiment. 相似文献
130.