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The photoisomerization of OClO (ClO2) to ClOO in a sulfuric acid glass at 20 to 77 K has been reinvestigated using electron spin resonance (ESR) to observe the reactant and product and to quantitatively determine their relative concentrations. Polarized light photolysis yields a partial orientation of the remaining ClO2 molecules (magnetophotoselection) and shows that the optical transition dipole moment lies in the molecular plane and is perpendicular to the ClO2 rotational symmetry axis, as expected for the well known A(2A2)←X(2B1) transition of ClO2. Here, however, the photolysis yields only ClOO, in contrast to the gas phase where ClO is observed suggesting photodissociation. The photoisomerization kinetics are nonexponential and suggest that random variations among the ClO2 trapping sites in the H2SO4 glass have a considerable effect on the probability that a photoexcited ClO2 molecule will isomerize. [ABSTRACT FROM AUTHOR]

The isotropic electron spin resonance (ESR) spectrum of HC17O has been observed in methane at 20 K (prepared by photolysis of HI in CH4 containing 1% of 17O enriched CO), and the isotropic oxygen hyperfine splitting determined [a0(HCO)=-15.1 G]. Isotropic spectra of HO2 (prepared similarly with O2 replacing CO) and NO2 in methane were also observed. Superhyperfine interactions in the ESR spectrum of H atoms in CH4 indicate H is trapped in the octahedral interstitial site of the matrix. ‘‘Forbidden’’ proton spin-flip transitions in the ESR spectrum of CH3 in methane indicate it is trapped at a substitutional site in the matrix. [ABSTRACT FROM AUTHOR]

Presents information on a study which described a method for the detection of superconductivity based on microwave resistivity. Advantages of the method; Results and discussion; Conclusions.

Discusses a study which analyzed the application of laser-induced forward transfer technique to 532 nanometer thin films using a frequency-doubled yttrium aluminum garnet laser. Methodology of the study; Deposition of copper; Theoretical model to explain copper depositions.

Presents a study which established the superconducting transition temperature in oxygen deficient perovskite yttrium barium[sub2]copper[sub3]oxygen[subz]. Experimental details; Speed of the reduction in the transition temperature with the increase in iron concentration in the sample; Results and discussion.

Presents a study that investigated the magnetic behavior of both superconducting thin films and their deposition targets. Importance of thin films in the electronic industry; Results and discussion.

Presents information on a study which compared the results of measurements on single crystals of YBa[sub2]Cu[sub3]O[sub7-x] using magnetically modulated microwave absorption and SQUID magnetometry. Magnetization of the single crystals; Experimental details; Results and discussion; Conclusions.

Presents information on a study which deposited thin films of Bi-Sr-Ca-Cu-O on crystalline quartz substrates by laser ablation (LA). Deposition of the films on crystalline quartz with and without an LA processing (LAP)-deposited zirconium oxygen[sub2] buffer layer; Discussion on the magnetically modulated microwave absorption technique; Description of the LAP method; Results of the x-ray diffraction analysis.

Presents information on a study that provided a method for the direct writing of metal features from a metal film supported on an optically transparent substrate using single pulse from a high-energy excimer laser. Experimental procedures; Results and discussion.

Exposure of the high Tc superconductor YBa2Cu3O7-δ to 60Co γ irradiation up to 1.3 Mrad is found to have virtually no effect on its superconductive properties as measured by a novel variant of the microwave absorption method. [ABSTRACT FROM AUTHOR]

Thin films of Bi-Sr-Ca-Cu-O, deposited on (100) cubic zirconia by laser ablation from a bulk superconducting target of nominal composition BiSrCaCu2 Ox , have been investigated by dc resistance and magnetically modulated microwave absorption measurements. The latter technique reveals important features regarding the phase purity of superconducting samples that are masked in the dc resistance measurements. The superconducting behavior of the films, as a function of the substrate temperature during deposition and the post-deposition annealing conditions, is discussed. [ABSTRACT FROM AUTHOR]