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In this paper the problem of finding the design efficiency is considered when a single observation is unavailable in a connected binary block design. The explicit expression of efficiency is found for the resulting design when the original design is a balanced incomplete block design or a group divisible, singular or semiregular or regular with 1>0, design. The efficiency does not depend on the position of the unavailable observation. For a regular group divisible design with 1>0, the efficiency depends on the position of the unavailable observation. The bounds, both lower and upper, on the efficiency are given in this situation. The efficiencies of designs resulting from a balanced incomplete block design and a group divisible design are in fact high when a single observation is unavailable.The work of the first author is sponsored by the Air Force Office of Scientific Research under Grant AFOSR-90-0092.On leave from Indian Statistical Institute, Calcutta, India. The work of the third author was supported by a grant from the CMDS, Indian Institute of Management, Calcutta.  相似文献   
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We investigate the change in the calculated value of asymptotic normalization constant (ANC) by the hyperspherical harmonics expansion method with the inclusion of three nucleon force (3BF) in addition to two nucleon force. We see that ANC does not change very much with the inclusion of 3BF indicating that the 3BF does not alter the asymptotic behaviours of HHE wavefunction significantly.  相似文献   
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We focus on the possible thermal channel of the well-known Lithosphere–Atmosphere–Ionosphere Coupling (LAIC) mechanism to identify the behavior of thermal anomalies during and prior to strong seismic events. For this, we investigate the variation of Surface Latent Heat Flux (SLHF) as resulting from satellite observables. We demonstrate a spatio-temporal variation in the SLHF before and after a set of strong seismic events occurred in Kathmandu, Nepal, and Kumamoto, Japan, having magnitudes of 7.8, 7.3, and 7.0, respectively. Before the studied earthquake cases, significant enhancements in the SLHF were identified near the epicenters. Additionally, in order to check whether critical dynamics, as the signature of a complex phenomenon such as earthquake preparation, are reflected in the SLHF data, we performed a criticality analysis using the natural time analysis method. The approach to criticality was detected within one week before each mainshock.  相似文献   
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It is shown that γ rays act on glycine to give the free radical NH3 +-?H-CO2 ? which remains trapped in the solid. Electron spin resonance spectra from an irradiated single glycine crystal show marked anisotropy and it is deduced that the radicals are precisely oriented in the crystal lattice. The symmetry shown by the spectra is consistent with that of the crystal lattice. Despite overlapping of lines, the spectra due to the NH3 +-?H-CO2 ? radical have been interpreted in terms of electronnucleus coupling tensors for the N, the H(C) and the three H(N) nuclei, the latter being equivalent by virtue of a rotation or tunnelling of the -NH3 + grouping. A qualitative interpretation of these tensors in terms of the electronic structure of the radical is given. This is consistent with the negative spin density on the H(C) atoms and a positive spin density on the H(N) atoms, as predicted by theoretical treatments. The radicals appear to be oriented in the lattice in approximately the same way as their parent molecules.  相似文献   
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Kinetic study has been performed to understand the reactivity of novel cationic gemini surfactants viz. alkanediyl‐α,ω‐bis(hydroxyethylmethylhexadecylammonium bromide) C16‐s‐C16 MEA, 2Br? (where s = 4, 6) in the cleavage of p‐nitrophenyl benzoate (PNPB). Novel cationic gemini C16‐s‐C16 MEA, 2Br? surfactants are efficient in promoting PNPB cleavage in presence of butane 2,3‐dione monoximate and N‐phenylbenzohydroxamate ions. Model calculation revealed that the higher catalytic effect of ethanol moiety of gemini surfactants (C16H33N+ C2H4OH CH3 (CH2)S N+ C2H4OH CH3C16H33, 2Br?, s = 4, 6) is due to their higher binding capacity toward substrate. This is in line with finding that binding constants for novel series of cationic gemini surfactants are higher than conventional cationic gemini (C16H33N+(CH3)2(CH2)SN+(CH3)2C16H33, 2Br?, s = 10, 12), cetyldimethylethanolammonium bromide and zwitterionic surfactants, i.e. CnH2n+1N+Me2 (CH2)3 SO3? (n = 10; SB3‐10). The fitting of kinetic data was analyzed by the pseudophase model. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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Kinetic studies of the reactions of tertiary oximes (monoisonitroso acetone; MINA and butane 2,3 dione monooxime; BDMO) with some carboxylate (p‐nitrophenyl acetate and p‐nitrophenyl benzoate), phosphate (p‐nitrophenyl diphenyl phosphate and bis (2,4‐dinitrophenyl) phosphate) and sulfonate (p‐nitrophenyl p‐toluene sulphonate) esters in gemini surfactants have been conducted. The observed first‐order rate constant versus surfactant profiles show micelle‐assisted bimolecular reactions involving interfacial ion exchange between bulk aqueous media and micellar pseudophase. Experimental results showed that MINA exhibited better nucleophilic activity towards ester cleavage than BDMO. Pseudophase model has been applied in order to determine micellar second‐order rate constants and binding constants. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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This paper presents a study of the experimental lower boundb L, on the root-mean-squared impact parameter of the multiparticle production in 70 GeV/c p-nucleon interaction. It has been observed that theb L decreases with increasing final state multiplicity (n) at this fixed energy. The results are in good agreement with those of other authors.The authors would like to thank Prof. K. D. Tolostov of Dubna, U.S.S.R. for kindly supplying the exposed emulsion plates.  相似文献   
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