Spin precession of channeled particles in bent crystals has been observed for the first time. Polarized Sigmasup + were channeled using bent Si crystals. These crystals provided an effective magnetic ...field of 45 T which resulted in a measured spin precession of 60plus minus17degree. This agrees with the prediction of 62plus minus2degree using the world average of Sigmasup + magnetic moment measurements. This new technique gives a Sigmasup + magnetic moment of (2.40plus minus0.46plus minus0.40)musub ital N, where the quoted uncertainties are statistical and systematic, respectively. We see no evidence of depolarization in the channeling process.
We report the first observation of the Cabibbo-suppressed charm baryon decay Ξ_{c}^{+}→pK^{-}π^{+}. We observe 150±22±5 events for the signal. The data were accumulated using the SELEX spectrometer ...during the 1996-1997 fixed target run at Fermilab, chiefly from a 600 GeV/c Σ^{-} beam. The branching fractions of the decay relative to the Cabibbo-favored Ξ_{c}^{+}→Σ^{+}K^{-}π^{+} and Ξ_{c}^{+}→Ξ^{-}π^{+}π^{+} are measured to be B(Ξ_{c}^{+}→pK^{-}π^{+})/B(Ξ_{c}^{+}→Σ^{+}K^{-}π^{+})=0.22±0.06±0.03 and B(Ξ_{c}^{+}→pK^{-}π^{+})/B(Ξ_{c}^{+}→Ξ^{-}π^{+}π^{+})=0.20±0.04±0.02, respectively.
We report new precision measurements of the lifetimes of the Lambda(+)(c) and D0 from SELEX, the charm hadroproduction experiment at Fermilab. Based upon 1630 Lambda(+)(c) and 10 210 D0 decays we ...observe lifetimes of tauLambda(+)(c) = 198.1+/-7.0+/-5.6 fs and tauD0 = 407.9+/-6.0+/-4.3 fs.
We report the first observation of the Cabibbo-suppressed charm baryon decay Xi(+)(c)-->pK(-)pi(+). We observe 150+/-22+/-5 events for the signal. The data were accumulated using the SELEX ...spectrometer during the 1996-1997 fixed target run at Fermilab, chiefly from a 600 GeV/c Sigma(-) beam. The branching fractions of the decay relative to the Cabibbo-favored Xi(+)(c)-->Sigma+K-pi(+) and Xi(+)(c)-->Xi(-)pi(+)pi(+) are measured to be B(Xi(+)(c)-->pK(-)pi(+))/B(Xi(+)(c)-->Sigma+K-pi(+)) = 0.22+/-0. 06+/-0.03 and B(Xi(+)(c)-->pK(-)pi(+))/B(Xi(+)(c)-->Xi(-)pi(+)pi(+)) = 0.20+/-0.04+/-0.02, respectively.
We have measured the branching ratio for the hyperon radiative decay Xisup minusr arrowSigmasup minusgamma from a sample of 211plus minus33 events obtained in the polarized 375 GeV/ital c charged ...hyperon beam at Fermilab. We find ital B(Xisup minusr arrowSigmasup minusgamma/Xisup minusr arrowLambdasup 0pisup minus)=(1.22plus minus0.23plus minus0.06)times10sup minus4 where the quoted errors are statistical and systematic, respectively. We have also obtained an indication that the sign of the asymmetry parameter of this decay is positive.
•Novel benzimidazole derivatives inhibitors have been studied.•Efficiency increases with increasing the number of benzimidazole segments.•Inhibition efficiency depends on the temperature and ...concentration of HCl medium.•The inhibitors adsorb on mild steel surface both physically and chemically.
Three novel benzimidazole derivatives, 2-aminomethyl benzimidazole (ABI), bis (2-benzimidazolylmethyl) amine (BBIA) and tri (2-benzimidazolylmethyl) amine (TBIA), have been studied as inhibitors for mild steel in 1.0M HCl. The three compounds prevent mild steel from corrosion by adsorption on the steel surface and forming insoluble complex with ferrous species. Inhibition efficiency increases with the increase in the number of benzimidazole segments in the molecules (TBIA>BBIA>ABI). Protection efficiency of the inhibitors depends on concentration of inhibitor, temperature and concentration of hydrochloric acid.
DNA sequences were generated for matK and ITS for 68 and 103 samples of Cornus to reconstruct a species level phylogeny of the genus. The results support the monophyly of most subgenera, except subg. ...Kraniopsis and subg. Cornus. Subgenus Kraniopsis was suggested to exclude C. peruviana from South America and subg. Afrocrania and subg. Sinocornus were nested within subg. Cornus. Four major clades corresponding to groups also recognizable by morphological differences were revealed: the big-bracted dogwoods (BB) including subg. Cynoxylon, subg. Syncarpea, and subg. Discocrania, the dwarf dogwoods (DW) including subg. Arctocrania, the cornelian cherries (CC) including subg. Cornus, subg. Sinocornus, and subg. Afrocrania, and the blue- or white-fruited dogwoods (BW) including subg. Kraniopsis, subg. Mesomora, and subg. Yinquania. This finding is consistent with previous studies with more limited sampling. The single South American species C. peruviana was found to be sister to the Asian C. oblonga of subg. Yinquania, adding a fourth intercontinental disjunction in the genus that was previously unknown. Species relationships within the subgenera were clearly resolved except for the relatively large subg. Syncarpea and subg. Kraniopsis. Phylogenetic analyses of total evidence combining morphology, matK, ITS, and previously published rbcL and 26S rDNA sequences resolved the relationships among subgenera as (BW(CC(BB,DW))). Biogeographic analyses using DIVA with or without fossils resulted in different inferences of biogeographic history of the genus, indicating the importance of fossil data in biogeographic analyses. The phylogeny based on the total evidence tree including fossils supports an origin and early Tertiary diversification of Cornus in Europe and multiple trans-Atlantic migrations between Europe and North America by the early Tertiary. It also supports that distribution of the few species in the southern hemisphere was not ancestral, but a result of migration from the north. This evidence rejects a previous hypothesis of a southern hemispheric origin of the genus.
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