New limit on the permanent electric dipole moment of 199Hg

We present the first results of a new search for a permanent electric dipole moment of the 199Hg atom using a UV laser. Our measurements give d(199Hg) = -(1.06+/-0.49+/-0.40)x10(-28)e cm. We interpret the result as an upper limit absolute value [d(199Hg)]<2.1x10(-28)e cm (95% C.L.), which sets new constraints on theta bar;(QCD), chromo-EDMs of the quarks, and CP violation in supersymmetric models.     

Cofactor Biogenesis in Cysteamine Dioxygenase: C−F Bond Cleavage with Genetically Incorporated Unnatural Tyrosine

Cysteamine dioxygenase (ADO) is a thiol dioxygenase whose study has been stagnated by the ambiguity as to whether or not it possesses an anticipated protein‐derived cofactor. Reported herein is the discovery and elucidation of a Cys‐Tyr cofactor in human ADO, crosslinked between Cys220 and Tyr222 through a thioether (C?S) bond. By genetically incorporating an unnatural amino acid, 3,5‐difluoro‐tyrosine (F₂‐Tyr), specifically into Tyr222 of human ADO, an autocatalytic oxidative carbon–fluorine bond activation and fluoride release were identified by mass spectrometry and ¹⁹F NMR spectroscopy. These results suggest that the cofactor biogenesis is executed by a powerful oxidant during an autocatalytic process. Unlike that of cysteine dioxygenase, the crosslinking results in a minimal structural change of the protein and it is not detectable by routine low‐resolution techniques. Finally, a new sequence motif, C‐X‐Y‐Y(F), is proposed for identifying the Cys‐Tyr crosslink.     

The synthesis of a fluorinated phthalocyanine

The reaction of perfluoroalkylcopper with 4-iodophthalonitrile provides a convenient route to fluorinated phthalonitriles which readily form phthalocyanines in the presence of stannous chloride dihydrate.During the course of preparing 4-perfluoroheptylphthalonitrile $\text{1}$, a secondary reaction was observed when the reaction time was extended beyond two hours. This reaction involves the interaction of the orthodinitrile with copper and/or cuprous iodide to afford the phthalocyanine nucleus. This coaction is portrayed by the appearance of a green color in the reaction media.     

A rapid-scan device for the determination of spectral line profiles in pulsed discharges

The results of a time-of-flight experiment are presented, in which the total cross-sections for 2–400 eV positrons on H₂, D₂, N₂, and CO were measured. Paper F7 presented at 3rd Internat'l. Conf. Positron Annihilation. Otaniemi, Finland (August 1973).     

Tensor analysing powers of (d,p) reactions on 28Si, 67Zn, 90Zr and 208Pb at 12.3 MeV

The tensor analysing powers T₂₀ and T₂₂ of(d, p) reactions leading to several states of the final nuclei ²⁹Si, ⁶⁸Zn, ⁹¹Zr and ²⁰⁹Pb were measured at 12.3 MeV deuteron beam energy. The measured tensor analysing powers together with the vector analysing power and cross-section data are compared with DWBA calculations with and without the deuteron D-state. The D-state effects and j-dependence of the tensor analysing powers are discussed. The spin transfers involved in populating the 1.08, 1.88 and 3.30 MeV states in ⁶⁸Zn in the ⁶⁷Zn(d, p)⁶⁸Zn reaction are deduced to be predominantly $\text{1}\text{2}{}^{\mathrm{?}}$. This implies an assignment for the 3.287 MeV level of ⁶⁸Zn of J^π = 2⁺.