Production of π±, K±, p and p̄ by 200 GeV/c protons

Data are presented on the relative yields of π^±, K^±, p and p? with momenta between 6 and 37 GeV/c produced at 0° by 200 GeV/c protons on beryllium and aluminium.     

Darstellung von Derivaten des Trimethoxybenzols

Zusammenfassung Es wird die Darstellung von 6,7,8-Trimethoxy-3-amino-chinazolonen-(4) durch Umsetzung der 2-Acylamino-3,4,5-trimethoxybenzoesäureester mit Hydrazinhydrat beschrieben.Außerdem berichten wir über die Halomethylierungsprodukte des Trimethoxybenzols und deren Verwendung zur Synthese neuer Verbindungen.     

Soft gluon emission and the QCD Λ mass parameter

We use a simple and transparent method for the resolution of the modified Altarelli-Parisi equation (including soft gluon emission) in the non-singlet case. We point out some of the phenomenological consequences of this modification. In particular, we show that the QCD Λ mass scale has to be lowered by a factor of two.     

LP11 mode cutoff: a simplified numerical approach

By combining the Ritz-Galerkin method with simple polynomial approximations, the calculation of the LP₁₁ mode cutoff in optical fibres with an arbitrary refractive index profile becomes simple enough to be carried out on any pocket calculator. The method is particularly accurate for singly-clad profiles and is applicable even to discrete numerical data from profile measurements.     

Peripherally metalated secoporphyrazines: a new generation of photoactive pigments

Base-catalyzed cross condensation of dipropylmaleonitrile 1 with bis(dimethylamino)maleonitrile 2 in an equimolar ratio afforded the porphyrazines 3a, 4a, 5a, 6a and 7a. Subsequent demetalation of 5a with TFA followed by remetalation with Zn(OAc)(2) gave ligand 5c in good yield. Compound 5c was, in turn, selectively oxidized and further peripherally functionalized using Pt(PhCN)(2)Cl(2) and PdCl(2) to yield the novel seco solitaire porphyrazines 10a and 10b. The photophysical profiles of the seco solitaire porphyrazines 10a and 10b were evaluated by means of absorption, emission, and transient absorption spectroscopy. The new pigments 10a and 10b were found to be photochemically more stable than the solitaire complexes 3d and 3e and mediated the generation of singlet oxygen with quantum yields of 0.59 and 0.45, respectively.     

Shear-induced first-order sponge-to-lamellar transition in a lyotropic surfactant system

We report a shear-induced sponge (L3) to lamellar (L(alpha)) transition in a surfactant system. Under a constant shear rate, after a delay time t(n) we observe random nucleation and subsequent growth of the L(alpha) phase, demonstrating that the shear-induced transition is first order. A simple argument for the energy of a two-dimensional nucleus accounts for the observed delay and its shear-rate dependence.     

Characterization of an oxaluric acid derivative as a guanine oxidation product

The oxidation of guanine in the dinucleoside monophosphate d(GpT) by an oxo-metalloporphyrin generates a linear oxaluric acid derivative after heating at 65 degrees C for 30 min and at neutral pH.     

Superimposed normal and superconducting films

Tunneling characteristicsdI/dV have been taken on both sides of “dirty”In - Bi/Zn superimposed films, the temperatureT being such thatIn - Bi was superconducting and Zn normal. Most of the attention has been devoted to the regionT～T _c where the experimental curves can be compared with a reasonably accurate microscopic theory. We find reasonable agreement for the voltage scale and, more important, for theamplitude of the effects in the superconducting phase.