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71.
A number of tests were performed to evaluate the feasibility of determining the deflections of a laterally loaded plate by means of stereo-photogrammetric methods. Mechanical measurements at several points were also made for each loading condition as well as performing an analytical solution for the centrally loaded case. A comparison of results indicated that this photogrammetric procedure used to determine deflections resulted in accuracies within ±0.020 in. Recommendations are made to improve greatly the accuracy potential of the stereo-photogrammetric method of deflection reading of a laterally loaded plate.  相似文献   
72.
Seeds of (the plant) P. Corylifolia Linn (Bawachi) known for their therepeutic value in indigenous medicine have been analysed for Cu, As, Sb and Se by thermal neutron activation analysis involving substoichiometric extraction and precipitation technique. The amounts of Cu, As, Sb and Se per gram of seeds dried at 80°C are 16.0±1.1 μg, 0.90±0.4 μg, 12.1±0.6 μg and 4.0±0.2 μg respectively.  相似文献   
73.
A high yield pyrrole synthesis which employs a sequence of cyclo-addition, photoextrusion of H2O and Birch reduction has been developed.  相似文献   
74.
Cyanoethylation of some dimethyl- and trimethylphenols in acidic and basic media has been investigated. The cyanoethyl derivatives obtained were hydrolysed to the corresponding acids which on cyclisation with PPA afforded either dihydrocoumarin or chromanone whose structures were assigned on the basis of chemical and spectral evidence.  相似文献   
75.
We present a measurement of the time-dependent CP-violating (CPV) asymmetries in B0-->K(0)(S)pi(0) decays based on 124x10(6) Upsilon(4S)-->BB decays collected with the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC. In a sample containing 122+/-16 signal decays, we obtain the magnitudes of the direct CPV asymmetry CK(0)(S)(pi(0))=0.40(+0.27)(-0.28)+/-0.09 and of the CPV asymmetry in the interference between mixing and decay SK(0)(S)(pi(0))=0.48(+0.38)(-0.47)+/-0.06 where the first error is statistical and the second systematic.  相似文献   
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Reactions of indoline (I), 2-methylindoline (II) and hexahydrocarbazole (III) with α,β-unsaturated acids in the presence of polyphosphoric acid have been investigated. Reaction of 1 with acrylic acid afforded two compounds which were identified as 1,2,4,5-tetrahydro-6H-pyrrolo-[3,2,1-ij] quinolin-6-one (IV) and 2,3,5,6,9,10-hcxahydro-1H-cyclopenta[f lpyrrolo [3,2,1-ij|-quinoline-1,8-dione (VII). The reaction oi 1 with crotonic acid gave compounds V and VIII, analogous-to IV and VII. The reaction of II with acrylic acid yielded two compounds VI and IX, whereas with crotonic acid, only X was isolated. With 111, acrylic acid afforded 5,6,8,9,10. 11,8a,11a-octahydro-4H-pyrido[3,2,1-jk]carbazol-4-one (XI) and a compound with a heretofore unknown ring system, viz., 2,3,5,6,7,8,11,12,5a,8a-decahydro-1H-cyclopenta[h] pyrido [3,2,1-jk |earbazole-1,10-dione. The structures of these compounds were deduced on the basis of their spectral and analytical data.  相似文献   
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