Establishing vicinal proton-proton connectivities using two-dimensional proton zero quantum coherence NMR

Phenanthro[3,4:3′,4′]phenanthro[2,1-b]thiophene ( 1 ) served as the model system to evaluate two-dimensional proton zero quantum coherence nmr in order to establish the vicinal proton-proton connectivities. The utility of the two-dimensional proton zero quantum nmr experiment has been compared with the utility of the traditional autocorrelated proton-proton (COSY) experiment. In the case of a molecule such as 1 , where the proton chemical shifts are so highly congested, the zero quantum coherence experiment provides data not obtainable from the COSY experiment.     

Disturbing the Dyson conjecture, in a generally GOOD way

Dyson's celebrated constant term conjecture [F.J. Dyson, Statistical theory of the energy levels of complex systems I, J. Math. Phys. 3 (1962) 140-156] states that the constant term in the expansion of _∏1≦i≠j≦naj(1−xi/xj) is the multinomial coefficient (a₁+a₂+?+an)!/(a₁!a₂!?an!). The definitive proof was given by I.J. Good [I.J. Good, Short proof of a conjecture of Dyson, J. Math. Phys. 11 (1970) 1884]. Later, Andrews extended Dyson's conjecture to a q-analog [G.E. Andrews, Problems and prospects for basic hypergeometric functions, in: R. Askey (Ed.), The Theory and Application of Special Functions, Academic Press, New York, 1975, pp. 191-224]. In this paper, closed form expressions are given for the coefficients of several other terms in the Dyson product, and are proved using an extension of Good's idea. Also, conjectures for the corresponding q-analogs are supplied. Finally, perturbed versions of the q-Dixon summation formula are presented.     

Samuelson maps—recent results

Samuelson maps are maps whose Jacobian matrix has nowhere vanishing leading principal minors. This paper surveys some recent results on invertibility of Samuelson maps and their decomposition into maps that fix all but one coordinate. The most noteworthy result is that real, rational, everywhere defined Samuelson maps are invertible. Proofs are sketched or omitted entirely.     

Investigation of the degradation of commercial polyoxymethylene copolymer in water service applications

An investigation has been carried out on the influence of degradation on various properties of commercial polyoxymethylene (POM) copolymer fittings in chlorinated cold water service lines. Scanning electron microscope (SEM) was used to document interior bulk morphological changes and typical defects. The various types of irregular cracks and pits were observed at the innerface of the samples. DSC and intrinsic viscosity determination were carried out for investigation of crystallinity and molecular weight changes. It was seen that the crystallinity of the POM increases at a much higher rate at the inner surface layers than the outer layer in the used samples. The FT-IR spectra of the new and used samples indicate the extent of degradation of the samples.     

A Bibliography on the Applications of Mathematical Programming Multiple-objective Methods

This paper gives a bibliography on applications of multiple-objective methods which use no a priori explicit value function and are complex enough to require mathematical programming aids. A commentary on the applications and on the survey is also given which may be helpful for further work of this kind. The survey covers the period 1955-86.     

On the physical interpretation of Heywood and Redhead's algebraic impossibility theorem

Heywood and Redhead's 1983 algebraic (Kochen-Specker type) impossibility proof, which establishes the inconsistency of a broad class of contextualized local realistic theories, assumes two locality conditions and two auxiliary assumptions. One of those auxiliary conditions, FUNC^*, has been called a physically unmotivated,ad hoc formal constraint.In this paper, we derive Heywood and Redhead's auxiliary conditions from physical assumptions. This allows us to analyze which classes of hidden-variables theories escape the Heywood-Redhead contradiction. By doing so, we hope to clarify the physical and philosophical ramifications of the Heywood-Redhead proof. Most current hidden-variables theories, it turns out, violate Heywood and Redhead's auxiliary conditions.1. See Redhead [1], pp. 133–136, for a complete discussion.2. Arthur Fine first pointed out the implicit reliance on FUNC^*, and proved FUNC^* to be both consistent with and independent of the Value Rule.3. LetA=_ia_i P _i andB=_jb_j P_j be spectral resolutions ofA andB. Then <A,B> is the observable associated with maximal operatorR=_ijf_ij P _iP_j, where f_ij=F(a_i,b_j), and where function F is 1:1.4. Heywood and Redhead's versions of these conditions employ equivalence-class notation to specify the ontological context. {<D,E>}={R} refers to the equivalence class of all possible <D,E> formed by using different F functions (cf. Footnote 3). Clearly, such notation assumes that ifR andR are two distinct commuting maximal operators formed as described in Fn. 3 fromD andE using two different F(d_i,e_j) functions, then [Q]^t _(R)(R)=[Q]^t _(R)(R), so that [Q]^t _{R}(R) is uniquely defined.Heywood and Redhead never rely upon this assumption in their proof, however. It is easily checked that a Heywood-Redhead contradiction follows from my non-equivalence class versions of OLOC, ELOC, VR, and FUNC^*. Therefore, I will not use equivalence class notation.5. Here I denote by µ_R the composite state of all the apparatuses needed to measure R. So µ_R may represent the state of more than one device.6 This is because in a hidden-variables framework, quantum mechanical probabilities are a weighted average of the underlying hidden-variables probabilities.7. This argument resembles a proof given by Fine [8].8. Recall from theorem 1 that ifQ=f(R), then for all quantum states , P_(t)(Qf(r), R=r)=0.     

Kaon production in\bar pp interactions at c.m. energies from 200 to 900 GeV

A detailed analysis ofK _s ⁰ production in \(\bar pp\) |<2.5 the average transverse momentum is found to be 0.53±0.07 GeV/c at 200 GeV and 0.62±0.08 GeV/c at 900 GeV, which is an increase with respect to data at c.m. energies below 60 GeV. TheK _s ⁰ production cross sections in inelastic collisions are 29±4 mb at 200 GeV and 63±6 mb at 900 GeV, showing an increase compared to lower energy data. The central kaon density is found to increase as a logarithmic function of energy. At 900 GeV, where statistics are sufficient to allow one to draw conclusions, the average transverse momentum is higher in events with large charged multiplicity than in events with low multiplicity.     

Observation and analysis ofE mesons in\bar p p annihilation at rest in H2 gas

Antiproton-proton annihilation at rest in a gaseous H₂ target at NTP into the final state π⁺ π^? K ^± π^? (K ⁰) with an undetectedK ⁰ or \(\bar K^0 \) has been investigated. We observe theE(1420) resonance in the invariant mass spectrum (K ⁰)_miss K ^± π^? with massM _E =1413±8 MeV/c² and widthГ ^E =62 ± 16MeV/c² and find evidence for the production of thef ₁(1285). The absolute branching ratio of \(\bar p\) p → π⁺ π^? E ⁰,E ⁰ →K ₀ ^L K ^± π ^? at (61±6)%P wave annihilation is (3.0±0.9)·10^?4 of all annihilations. The observed suppression of theE production fromP wave with respect to theS wave together with some simple selection rules suggest that the quantum numbers of theE(1420) areJ ^pc=0^?+ and not I⁺⁺.