Small point sets of PG(n, p 3h ) intersecting each line in 1 mod p h points

The main result of this paper is that point sets of PG(n, q), q = p ^3h , p ≥ 7 prime, of size < 3(q ^n-1 + 1)/2 intersecting each line in 1 modulo ${\sqrt[3] q}$ points (these are always small minimal blocking sets with respect to lines) are linear blocking sets. As a consequence, we get that minimal blocking sets of PG(n, p ³), p ≥ 7 prime, of size < 3(p ^3(n-1) + 1)/2 with respect to lines are always linear.     

EFFECT OF INACTIVATION OF THE OXYGEN-EVOLVING SYSTEM ON THE THERMOLUMINESCENCE OF ISOLATED CHLOROPLASTS

Abstract— The effect of inactivation of water-splitting enzyme on the thermoluminescence of isolated chloroplasts was investigated. The inhibitory treatments used included Tris-washing, alkaline pH in the presence of the uncoupler gramicidin, incubation with a high concentration of magnesium ions and different chaotropic agents. It was found that inhibition of oxygen evolution resulted in the disappearance of the main thermoluminescence band at +20°C. The A band which appears at — 10°C and has been related to the S₄ state of the water-splitting enzyme (Inoue, 1981) was not considerably affected by the inhibition of oxygen evolution. The results presented here indicate that the participation of the S₄ state of water-splitting enzyme in the generation of the A band should be reinvestigated.     

Approaching unit visibility for control of a superconducting qubit with dispersive readout

In a Rabi oscillation experiment with a superconducting qubit we show that a visibility in the qubit excited state population of more than 95% can be attained. We perform a dispersive measurement of the qubit state by coupling the qubit non-resonantly to a transmission line resonator and probing the resonator transmission spectrum. The measurement process is well characterized and quantitatively understood. In a measurement of Ramsey fringes, the qubit coherence time is larger than 500 ns.     

Femtosecond pulse-shape modulation at nanosecond rates

We report high-rate, computer-controlled femtosecond pulse shaping by use of an electro-optical gallium arsenide optical phased-array modulator with 2304 controlled waveguides. It provides fast modulation speed of both spectral phases and amplitudes. Limited by the driving electronics of our current setup, we were able to update a pulse shape in approximately 30 ns. This technique paves the way toward individual shaping of every single pulse of typical femtosecond mode-locked oscillators.     

Hydrogen abstraction from fluorinated aliphatic acids

1,3-Dichlorotetrafluoroacetone has been photolysed at a wavelength of 313nm in the presence of fluorinated aliphatic acids, such as trifluoroacetic acid, pentafluoropropionic acid, heptafluorobutyric acid and chlorodifluoroacetic acid. From the rates of formation of chlorodifluoromethane and 1,2-dichlorotetrafluoroethane, the rate constants and energies of activation for the hydrogen abstraction reaction were calculated. No products were observed which could arise from the decomposition of the alkyl carboxyl radical produced during the hydrogen abstraction reaction

     

Oxidation of 2,6-xylenol by Co(III) chelates in toluene

A simple reaction scheme and kinetic data are presented for the oxidation of 2,6-xylenol by Co(III) chelates in toluene.

---

2,6- Co(III) .