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Fusion cross-sections for the 7Li + 12C reaction have been measured at energies above the Coulomb barrier by the direct detection of evaporation residues. The heavy evaporation residues with energies below 3 MeV could not be separated out from the α-particles in the spectrum and hence their contribution was estimated using statistical model calculations. The present work indicates that suppression of fusion cross-sections due to the breakup of 7Li may not be significant for 7Li + 12C reaction at energies around the barrier.  相似文献   
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Clavulanic acid (CA) is frequently prescribed for treatment of bacterial infections. Despite the large number of studies concerning CA production, there is still a need to search for more effective and productive processes because it is mainly produced by biochemical route and is chemically unstable. This paper evaluates the influence of acid and cold stresses on CA production by Streptomyces clavuligerus in bench scale stirred tank bioreactor. Four batch cultures were conducted at constant pH (6.8 or 6.3) and temperature (30, 25, or 20 °C) and five batch cultures were performed with application of acid stress (pH reduction from 6.8 to 6.3), cold stress (reduction from 30 to 20 °C), or both. The highest maximum CA concentration (684.4 mg L−1) was obtained in the culture conducted at constant temperature of 20 °C. However, the culture under acid stress, in which the pH was reduced from 6.8 to 6.3 at a rate of 0.1 pH unit every 6 h, provided the most promising result, exhibiting a global yield coefficient of CA relative to cell formation (YCA/X) of 851.1 mgCA gX−1. High YCA/X values indicate that a small number of cells are able to produce a large amount of antibiotic with formation of smaller amounts of side byproducts. This could be especially attractive for decreasing the complexity and cost of the downstream processing, enhancing CA production.

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Mechanism of copper underpotential deposition at stepped faces of platinum single crystals Pt(hkl) is studied using cyclic voltammetry, scanning probe microscopy, and quantum-chemical modelling. It is shown that the first stage of UPD is one-dimensional decoration of the (100)- or (110)-orientated steps, then copper monolayer forms at (111)-terraces. The final stage is the secondary step decoration. Quantum-chemical modelling, with the using of long-distance potentials of the Cu-Pt and Cu-Cu pair interactions, allows estimating the energy of copper adsorption at different structure elements of the substrate (steps, kinks, terraces) and revealing the succession of the adatom monolayer formation; it also provides additional information for the identifying of the nature of voltametric peaks for different stages of the copper adsorption-desorption.  相似文献   
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Summary The Liquid Scintillation Detector (LSD experiment) is running since October 1984 in the Mont Blanc Laboratory, with 90 tons of active mass. We discuss here some of the research aims of the experiment, and report the preliminary results on searching for neutrino bursts from collapsing stars and on cosmic-ray muons.
Riassunto Nell'ottobre 1984 è entrato in misura l'esperimento LSD (Liquid Scintillation Detector) del Laboratorio del Monte Bianco, costituito di 90 tonnellate di rivelatore. In questo lavoro si discutono alcuni degli argomenti di ricerca dell'esperimento e si riportano i risultati preliminari sui burst di neutrini da collassi stellari e sui muoni della radiazione cosmica.

Резюме Зидкий сцинтилляционный детектор работает с октября 1984 года в лаборатории на Мон Блане. Детектор имеет 90 тонн активной массы. Мы обсуздаем некоторые цели этого эксперимента. Сообщаются предварительные результаты по поиску нейтринных вспышек от коллапсирующих звезд и мюонов в космических лучах.
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Summary We discuss here the results from calibrating liquid seintillation counters (1.5 m3 each) used in the large-volume neutrino experiment in the Mont Blanc Laboratory. The electronic and recording systems from the 72 counters of the detector are described, and the method to detect low-energy γ pulse from (n, p) reaction by using252Cf as a neutron source is discussed. Paper presented at the 2° Convegno Nazionale di Fisica Cosmica, held at L'Aquila, 29 May–2 June 1984.  相似文献   
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