Exotic phases of finite temperature gauge theories

We calculate the phase diagrams at high temperature of SU(N) gauge theories with massive fermions by minimizing the one-loop effective potential. Considering fermions in the adjoint (Adj) representation at various N we observe a variety of phases when N_f2 Majorana flavours and periodic boundary conditions are applied to fermions. Also the confined phase is perturbatively accessible. For N=3, we add Fundamental (F) representation fermions with antiperiodic boundary conditions to adjoint QCD to show how the Z(3)-symmetry breaks in the confined phase.     

An inductively coupled plasma-time-of-flight mass spectrometer for elemental analysis. Part III: Analytical performance

A time-of-flight mass spectrometer (TOFMS) was evaluated as a mass analyzer for inductively coupled plasma mass spectrometry (ICP-MS). The long-term drift of signals was in the range of 7–8% relative standard deviation, whereas the short-term precision was between 5 and 20%, somewhat worse than is typically reported for commercial ICP-MS instruments (5%). However, precision can be improved considerably in the TOFMS by ratioing isotopic peaks or through internal standardization, a consequence of its ability to extract all measured ions simultaneously from the inductively coupled plasma. This feature was demonstrated by monitoring the ²⁰⁶Pb/²⁰⁸Pb ratio with boxcar averagers. In this ratioing mode, precision was improved to approximately 0. 5%. Detection limits were measured with two alternative signal processing systems: (1) discriminator-gated integration and (2) integration of digitized spectra. Both methods improved the signal-to-noise ratio by a factor of from 10 to 100, although detection limits were still 1–2 orders of magnitude poorer for most elements than from the best commercial ICP-MS instruments. The dynamic range of the discriminator-gated integration system is over 4 orders of magnitude, but can be extended to 10⁶ with planned increases in primary ion-beam current, which is currently 10–100 times lower than is found in other instruments. Virtually simultaneous multielement and multiisotope analysis is possible for masses from ⁷Li to ²⁰⁹Bi with minimal mass bias and detection limits on the 0. 4–2-ppb level.     

Resonance fluorescence spectrum of nitrogen dioxide

We report an investigation of the resonance fluorescence spectrum of NO₂ excited by several laser lines. Sixty transitions, mostly in ν₂ progressions of the ground state, have been assigned. Analysis of the spectra extend the knowledge of the ground state constants, especially of the anharmonic coefficients. It is possible to establish that transitions are occurring to a ²B₁ state and to a ²B₂ state in the same energy region.     

A semiempirical SCF MO study of the interaction of odorant molecules with a biological substrate

The AM 1 semiempirical SCF MO method developed by Dewar and co-workers has been employed to compute possible interaction processes of the odorant molecules cocaine, methyl benzoate, and benzaldehyde with the biological substrate lysine. The only process predicted as possible in each case was nucleophilic attack on the carbonyl carbons of each odorant by the nitrogen lone pairs on lysine. The remote amino group of lysine in each case was predicted to react with lower activation enthalpy than did the α-amino group, a prediction consistent with preliminary experimental data from these laboratories. Although the computed activation enthalpies were high (ca. 40 kcal mol^?1) for the gas-phase processes, it is conceivable that such processes could occur by alternate pathways with considerably lower ctivation energies in solvated media such as exists in the presence of mucus-containing olfactory binding protein in vertebrate olfactory reception. © 1992 John Wiley & Sons, Inc.     

External cavity quantum cascade laser for quartz tuning fork photoacoustic spectroscopy of broad absorption features

We demonstrate mid-infrared spectroscopy of large molecules with broad absorption features using a tunable external cavity quantum cascade laser. Absorption spectra for two different Freons are measured over the range 1130-1185 cm(-1) with 0.2 cm(-1) resolution via laser photoacoustic spectroscopy with quartz tuning forks as acoustic transducers. The measured spectra are in excellent agreement with published reference absorption spectra.     

A new solution for the rotation-driven spreading of a thin fluid film

Lie groups are used to solve the equation governing the flow of a thin liquid film subject to centrifugal spreading and viscous resistance. A new implicit solution is found. It is shown how this relates to the previous known solutions for the spreading of an initially flat film, the steady state and a separable solution. New permissible forms for the film evolution are also studied, including solutions exhibiting finite time blow-up. Near the contact line, where the film height tends to zero, an approximate explicit solution is obtained which may be used to describe a film with any size contact angle.     

Countercations direct one- or two-electron oxidation of an Al(III) complex and Al(III)-oxo intermediates activate C-H bonds

Hydrogen abstraction by aluminum(III)-oxo intermediates via reaction pathways reminiscent of late transition metal chemistry has been observed. Oxidation of M(+)[(IP(2-))(2)Al](-) (IP = iminopyridine, M = Na, Bu(4)N) yielded [Na(THF)(DME)][(IP(-))(IP(2-))Al(OH)] (3) or [(IP(-))(2)Al(OH)] (4), via O-atom transfer and subsequent C-H activation or proton abstraction, respectively.     

Application of the combined integral method to Stefan problems

In this paper we present a new, accurate form of the heat balance integral method, termed the combined integral method (CIM). The application of this method to Stefan problems is discussed. For simple test cases the results are compared with exact and asymptotic limits. In particular, it is shown that the CIM is more accurate than the second order, large Stefan number, perturbation solution for a wide range of Stefan numbers. In the initial examples it is shown that the CIM reduces the standard problem, consisting of a PDE defined over a domain specified by an ODE, to the solution of one or two algebraic equations. The latter examples, where the boundary temperature varies with time, reduce to a set of three first order ODEs.     

Storable arylpalladium(II) reagents for alkene labeling in aqueous media

We show that arylpalladium(II) reagents linked to biotin and indocyanine dye residues can be prepared by decarboxylative palladation of appropriately substituted electron-rich benzoic acid derivatives. When prepared under the conditions described, these organometallic intermediates are tolerant of air and water, can be stored for several months in solution in dimethyl sulfoxide, and permit biotin- and indocyanine dye-labeling of functionally complex olefinic substrates in water by Heck-type coupling reactions.