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Our research has investigated the use of C[F.sub.3]I, which has lower Global Warming Potential (GWP), as a substitute gas for [SF.sub.6]. The use of pure C[F.sub.3]I in gas insulated switchgear (GIS) and gas circuit breakers (GCB) is difficult because liquid C[F.sub.3]I has a high boiling point. We have therefore mixed C[F.sub.3]I with C[O.sub.2] or [N.sub.2]. By investigating the decomposed gas after a current interruption, we have shown that the iodine density from C[F.sub.3]I-C[O.sub.2](30%-70%) is about 1/3 of that of pure C[F.sub.3]I. in addition, no fluorine was detected from the gas mixture. Our investigation of the breakdown voltage characteristics has shown that the dielectric strength of C[F.sub.3]I-C[O.sub.2] (30%-70%) is about 0.75 to 0.80 times that of [SF.sub.6]. In Breaker Terminal Fault (BTF) and Short Line Fault (SLF) interruption, C[F.sub.3]I-C[O.sub.2] is superior to C[F.sub.3][I-[N.sub.2]. Because of the high boiling point of C[F.sub.3]I, the proportion of C[F.sub.3]I should be small. In BTF interruption, the performance approximates to that of pure C[F.sub.3]I when the proportion of C[F.sub.3]I exceeds 30%. Similarly, the SLF interruption performance approximates to that of pure C[F.sub.3]I when the proportion of C[F.sub.3]I exceeds 20%. Index Terms--C[F.sub.3]I, Breaker Terminal Fault (BTF), substitute gas for S[F.sub.6].

We studied the interruption performance of [CF.sub.3]I gas because its environmental effect is smaller than that of [SF.sub.6] gas with a model arc-extinguishing chamber. First, we measured the arc time constant and arc power loss coefficient using Mayr's equation. Comparing [CF.sub.3]I with other gases, the arc time constants are [SF.sub.6] < [CF.sub.3]I < [CO.sub.2] < [H.sub.2] < Air < [N.sub.2]. The arc power loss coefficient is [H.sub.2] > [SF.sub.6] > [CO.sub.2] > Air > [N.sub.2] > [CF.sub.3]I. Next, we evaluated the Short Line Fault (SLF) interruption capability by measuring the di/dtdv/dt characteristic. Consequently, the SLF interruption performance of pure [CF.sub.3]I was about 0.9 times that of [SF.sub.6]. However, [CF.sub.3]I application to gas insulated switchgear (GIS) and gas circuit breakers (GCB) is difficult because the liquefying temperature of the gas is high. Therefore, we adopted a countermeasure to obtain a lower liquefying temperature mixing [CF.sub.3]I with [CO.sub.2]. The result showed that the SLF interruption performance of the mixture approximated that of pure [CF.sub.3]I when the ratio of [CF.sub.3]I exceeds 20%. Index Terms--[CF.sub.3]I, short line fault (SLF), substitute gas for [SF.sub.6].

The electric deflections of p- and m-aminobenzonitrile (PABM and MABN) and of p- and m-(dimethylamino)benzonitrile (PDMABN and MDMABN) molecules are presented. The change in symmetry and the introduction of methyl groups have led to a transition from the rigid response to the linear response.

Molecular orbital signatures of the methyl substituent in L-alanine were identified with respect to those of glycine by using dual space analysis. In comparison to glycine, relaxation in geometry and valence orbitals in L-alanine is found as a result of the attachment of the methyl group and five orbitals rather than four orbitals are identified as methyl signatures.

The influence of the internal bias field on the domain dynamics during switching and spontaneous back-switching process in unipolar methylammonium bromobismuthate (CH3NH3) 5Bi2Br11, single crystal is investigated. This effect is examined by electrical switching measurements and observation of the domain structure.

An anharmonic vibrational Hamiltonian for the amide I, II, III, and A modes of N-methyl acetamide (NMA), recast in terms of the 19 components of an external electric field and its first and second derivative tensors (electrostatic DFT map), is calculated. Strong correlations are found between NMA geometry and the amide frequency fluctuations.

Metal-organic molecular-beam epitaxy with trimethylgallium and ammonia is used to grow GaN on Si(111). Analysis of the growth data reveals an increase in the apparent formation energy E(sub app) of epitaxial GaN from 0.168 to 0.56 eV with an increasing flux of ammonia.

X-ray reflectivity and surface tensiometry was used to study the surface structure and thermodynamics of two ionic liquids, based on the 1-alkyl-3-methylimidazolium cations. Details of the different possible molecular arrangements within the enhanced-density surface layer are discussed.

A methodology for the determination of solution structures of small molecules from residual dipolar coupling constants measured in dilute liquid crystals is developed. The study shows that reducing the degree of order by using dilute liquid crystralline media in combination with precise measurement of small residual dipolar coupling constants, is a way of overcoming the limitation of strongly orienting liquid crystals associated with the complexity of 1H NMR spectra for molecules with more than 12 protons.

Photochemical reduction of several 4-picolyl- and N-methy-4-picolinium esters is examined using product analysis, laser flash photolysis, and fluorescence quenching. It is demonstrated that the radical (anions) formed in these reactions readily fragment t yield a carboxylic acid and a 4-pyridylmethyl radical intermediate.

The spectra of C8H4 and C10H5 are observed in a butadiyne/argon discharge under the same conditions as those whereby C7H2 and C9H3 are found to dominate the spectroscopy. The results are discussed in terms of the chemistry of plasmas and the interstellar medium.

New infrared data are provided for disilylmethane-d0 and -d6 in the gas phase. The two possible kinds of SiH bonds are found to be identical in strength but not in electrical properties.

Electrochemical reduction of p-methyl-, p-methoxy-, and 3,5-dinitrophenyl thiocyanates, p-methyl- and p-methoxyphenyl disulfides were investigated in the acetronitrile at an inert electrode. The series of compounds revealed a striking change in the reduction cleavage mechanism of the S-CN bond in thiocyanates as a function of the substituent on the aryl ring in the aryl thiocyanate.

The (super 1)H-(super 1)H residual dipolar couplings have been measured in two alignment media for 57 out of 70 possible methyl containing residues in the 167-residue flavodoxin-like domain of the E. coli sulfite reductase. Experiments are described for the measurement of proton-proton dipolar couplings in CH2D methyl groups of (super 13)C labeled, highly deuterated (70-80%) proteins.

A study of the anharmonic corrections for the out-of-plane (OPLA) vibrational modes of CH(sub 2)Cl, CH(sub 2)F and CH(sub 30) radicals, which are calculated, is presented. The results show that the halogen substitution increases the anharmonicities dramatically, from 19% in CH(sub 3) up to about +/-100% in CH(sub 2)Cl and CH(sub 2)F.

The nitroxide spin probe 16-doxylstearic acid methyl ester is studied under conditions in which the spin probe undergoes spin exchange varying from slow exchange to high exchange leading to collapse of the three (super 14)N hyperfine lines into a single line. For an inhomogenously broadened line, the broadening must be extracted from the lorentzian component of the Voigt shape at low values of Omega e.

A two-dimensional hydrogen spin diffusion experiment is shown initiating the magnetization transfer from the methyl protons as the lipid chain termini provides useful topological information about membrane proteins. The enhanced spin diffusion of hydrogen is due to the rigid transmembrane protein segments, which are also detected through the lipid (super 31)P resonance.

The electronic spectrum of the H2COH radical is reinvestigated using the ab initio multireference configuration interaction (MRDCI) method, an AO basis set containing two sets of s and p Rydberg functions, and diagonalized CI spaces on the order of 2.5 x 10(super 5). The analysis reveals that excitation energies obtained with truncated CI spaces overestimate the corresponding extrapolated and estimated full CI energies.

The barrier to internal rotation of a methyl group attached to an unsaturated linkage in an organic molecule is changed by complex formation with a weakly bound argon atom. This is a result of a dispersion interaction between the argon and pie-electrons of the molecule in the vicinity of the methyl group.

Cluster ions composed of the alkyl nitriles, acetonitrile and butyronitrile and methyl cation were examined in an effort to study methyl cation affinities and the intrinsic nucleophilicity of these bases. According to molecular orbital calculations, the most stable structure of methyl cation-bound nitrile dimmers involves a neutral nitrile molecule covalently bonded to the carbon of the methylated cycno group.

Conventional infrared absorption and Raman spectroscopy are used to record the vapor phase spectra of methylpyridine-2-alphad2, 6-d1, methylpyridine-2-alphad2, and methylpyridine-3-aipha d2,-d4 in the deltaEpsilon(sub CH). For both compounds, Raman spectra are similar and as energy increases, the rotational potential is increasingly distorted.

A computational study is conducted on dithia-anthracenophane (DTA), for which experimental evidence is provided for coherent resonance energy transfer dynamics, and on dimethylanthracene (DMA), a molecule representing the energy donor and the acceptor in DTA. The results have shown that inelastic effect due to torsional motion cannot be ignored in DTA.

Time-resolved spectroscopy is used for comparing the photoinitiated charge separation (CS) and recombination (CR) in a series of donor-bridge-acceptor (D-B-A) molecules with cross-conjugated, linearly conjugated and saturated bridges. Molecular conductance calculations on the bridges have shown that cross-conjugation has resulted in quantum interference effects that have altered the through-bridge donor-acceptor electronic coupling as a function of charge injection energy.

The various different topographies exhibited by the plasma-hardened surfaces of the silicon elastomer poly(dimethylsiloxane) compound are analyzed. Flar, wrinkled, cracked and cracked and wrinkled are shown to be the four main topographies exhibited by the system.

Molecular dynamics simulation studies of the structure and the differential capacitance (DC) for the ionic liquid (IL) N-methyl-N-propylpyrrolidinium bis(trifluoromethane)sulfonyl imide near a graphite electrode are performed as a function temperature and electrode potential. A decreased DC and the disappearance of the minimum in DC near the potential of zero charge (PZC) with increasing temperature are due to the increasing importance of entropic/excluded volume effects with increasing temperature.

A newly developed strategy consisting of allylsilane ring-closing metathesis and subsequent SE' electrophilic desilylation (allylsilane RCM/SE') to construct exo-methylidenecycloalkanes is described. The method helped to identified a novel metal alkylidene-promoted deallylation reaction of terminal 1,4-dienes and provided a possible mechanism for the unexpected deallylation reaction of 1,4-dienes.

The interaction of oxygen atoms with three types of plasma enhanced chemical vapor deposition low-k SiOCH films is analyzed. Monte Carlo model is developed for O atom interaction with low-k material that includes penetration, recombination and reaction with methyl groups and the surface recombination on the pore wall surface has determined the profile and penetration depth of O atoms into the films.

The syntheses of several derivatives of two new dye systems, with one or two dialkylamino donor groups attached to resonant positions at the periphery of a trioxatriangulenium ion, are described. The optical properties of the new triangulenium dyes and their triphenylmethylium (TPM) precursors are examined and are shown to be dependent on symmetry and charge localization in the conjugated framework.

The article presents a new methodology, which uses the [1.sup]H relaxation dispersion phenomenon for the quantification of the [13.sup]CH[D.sub.2] methyl group probes of millisecond time scale exchange in proteins. The application of the technique for the analysis of proteasome gating residue dynamics is also discussed.

Organic two-step spin-transition-like behavior in a linear S = 1 array which simultaneously exhibit intermolecular antiferromagnetic coupling and intramolecular ferromagnetic coupling are described. The solid-soild phase transition oberved in the 3'-methylbiphenyl-3,5-diyl bis(tert-butylnitroxide) and related compounds in single-crystal-to-single-crystal manner are also described.