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71.
72.
R.P. Malik 《The European Physical Journal C - Particles and Fields》2008,55(4):687-698
We discuss various symmetry properties of the Lagrangian density of a four- (3+1)-dimensional (4D) free Abelian 2-form gauge
theory within the framework of Becchi–Rouet–Stora–Tyutin (BRST) formalism. The present free Abelian gauge theory is endowed
with a Curci–Ferrari type condition, which happens to be a key signature of the 4D non-Abelian 1-form gauge theory. In fact,
it is due to the above condition that the nilpotent BRST and anti-BRST symmetries of our present theory are found to be absolutely anticommuting in nature. For the present 2-form theory, we discuss the BRST, anti-BRST, ghost and discrete symmetry properties
of the Lagrangian densities and derive the corresponding conserved charges. The algebraic structure, obeyed by the above conserved
charges, is deduced and the constraint analysis is performed with the help of physicality criteria, where the conserved and
nilpotent (anti-) BRST charges play completely independent roles. These physicality conditions lead to the derivation of the above Curci–Ferrari type restriction, within the framework
of the BRST formalism, from the constraint analysis.
PACS 11.15.-q; 12.20.-m; 03.70.+k 相似文献
73.
A simple and sensitive capillary electrophoretic method was developed for the separation and determination of Ziram and Zineb in boric acid buffer by direct UV absorbance detection at lambda=254 nm. The separation is dependent on pH and nature of the buffer. The detection limits (S/N=3) are 1.88x10(-6) mol/l (0.57 mug/ml) and 2.48x10(-6) mol/l (0.68 mug/ml) for Ziram and Zineb, respectively. The method was successfully applied to the analysis of wheat samples spiked with Ziram and Zineb. 相似文献
74.
75.
Polarographic reduction of 2-amino-4-aryl-5-phenylazothiazoles takes place in a single 2-electron transfer, giving a diffusion-controlled irreversible wave in the pH range 2.0-10.0. Substituents in the 4-position of the thiazole moiety shift the half-wave potential through conjugation of the system. A correlation of E(sol;1 2 ) with the Brown and Hammett substituent constant has also been established. 相似文献
76.
77.
The time-differential perturbed angular correlation (TDPAC) experiments involving the 133–482 keV γ-γ cascade in181Ta have been performed in the presence of an external magnetic field along the quantization axis to measure the hyperfine magnetic field experienced by181Ta nuclei at the Hf site in the pseudobinary compounds HfFe2?xSix with x=0.1 and x=0.3. The hyperfine magnetic fields measured at 298 K are Hhf=133.1±12.0 kG in the cubic (C15) Laves phase compound HfFe1.9Si0.1 and Hhf=76.8±7.0 kG in the hexagonal (C14) Laves phase compound HfFe1.7Si0.3. The measured hyperfine fields are discussed within the framework of the Campbell-Blandin model. 相似文献
78.
Auerbach LB Burman RL Caldwell DO Church ED Cochran AK Donahue JB Fazely AR Garvey GT Gunasingha RM Imlay RL Kahrimanis G Louis WC Majkic R Malik A McIlhany KL Metcalf WJ Mills GB Rupnik D Sandberg VD Smith D Somodi RF Stancu I Strossman WD Sung M Tayloe R VanDalen GJ Vernon W Wadia N White DH Yellin S Yi H;LSND Collaboration 《Physical review letters》2004,92(9):091801
We observe a net beam excess of 8.7+/-6.3(stat)+/-2.4(syst) events, above 160 MeV, resulting from the charged-current reaction of nu(micro) and/or nu;(mu) on C and H in the LSND detector. No beam-related muon background is expected in this energy regime. Within an analysis framework of pi(0)-->nu(mu)nu;(mu), we set a direct upper limit for this branching ratio of Gamma(pi(0)-->nu(mu)nu;(mu))/Gamma(pi(0)-->all)<1.6 x 10(-6) at 90% confidence level. 相似文献
79.
Riaz N Anis I Malik A Ahmed Z Aziz-ur-rehman Muhammad P Nawaz SA Choudhary MI 《Chemical & pharmaceutical bulletin》2003,51(3):252-254
Paeonins A and B, new monoterpene galactosides have been isolated from the chloroform-soluble fraction of the roots of Paeonia emodi and showed potent lipoxygenase inhibitory activity. The structures of 1 and 2 have been assigned on the basis of spectral analysis including one- and two-dimensional NMR techniques. 相似文献
80.