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Preparation of silicon avalanche photodiodes by a planar method in epitaxial PP+ silicon slices limited charge collection to carriers generated in or close to the depletion region. Reducing the effective size of the zero-field absorption region surrounding the depletion region by this method, resulted in the output signal current of the device reproducing the input light pulse shape, within 15 ns. When illuminated with monochromatic radiation, the shot noise of a detector prepared in epitaxial material was less than that observed with a device fabricated in homogeneous material, due to the reduced signal current.

The gas phase electron resonance spectra of 17 OH and 17 OD are described. Analysis of the spectra yields values for the 17 O magnetic hyperfine and electric quadrupole parameters. The measured parameters are compared with those predicted by a number of different molecular wavefunctions which have been calculated for OH.

The electron resonance spectra of the J = 3/2 and J = 5/2 rotational levels of the 2 II 3/2 state of SeH and the J = 3/2 rotational level of the 2 II 3/2 state of SeD are described. Values of the rotational constant and Λ-doubling parameters are determined. Evidence is found for a tensorial interaction of the spin and magnetic field, arising from the gauge invariance requirement of the spin-orbit coupling Hamiltonian. Hyperfine structure from 77 Se is observed, and the hyperfine coupling constants are determined. The effect of an electric field on the spectra is analysed and the electric dipole moment determined.

The N.M.R. data for cyclopropane dissolved in a liquid crystal are treated with allowance for vibrational motion and a substantial improvement in the consistency of the data is obtained. Furthermor...

The preparation and the properties of the N -tributyltin pyrrole are investigated. With halides, a substitution occurs with its orientation depending on the compound in the reaction: with silicon halides, N -substituted pyrroles are obtained, whereas with organic halides most of the products are C -substituted derivatives. In order to explain these results, the hypothesis of the existence of a pyrrolenine intermediate is postulated. The synthesis of the 2-trimethylsilylpyrrole is then performed. This compound is unstable and converts slowly into the N -isomer.

The oriented chemical growth of the oxides are studied on different surfaces of single crystals of zinc and cadmium and also of the sulphide of cadmium. The contact planes between substrate and oriented overgrowth were found by determining the facets upon which a particular orientation occurs. The orientation is found to depend on the type of facet, and hence on the surface topography of the substrate which could be determined in favourable cases. The clean surfaces of the metallic crystals used were prepared by electrolytic methods. The inner potentials of zinc and zinc oxide have been measured.

The applicability of an r-centroid approximation to polyatomic molecules is discussed. The transformation between sets of normal coordinates for the same distorted molecule, but related to different reference configurations is investigated and shown to be a function of the distortion. The significance of this fact for the interpretation of Franck-Condon factors in polyatomic molecules is examined in relation to other approximations currently made.

I had long since returned my humble thanks to the Royal Society for their candid acceptance of my paper; and particularly to you for your most obliging letter, had I not thought a farther account of what I have observed in the fire, would be more acceptable to that illustrious body; particularly to the honourable Mr. Boyle, for whose ingenious queries I give him most hearty thanks, accounting my self happy, that by this occasion any thing of mine should come under the consideration of so worthy a person.

Bei normaler Ernahrung und taglichem Trinken von beliebigen Mengen 40% igem Zuckerrohrschnaps wurden bei weissen Laboratoriumsratten diverse anatomische und ultrastrukturelle Lungenveranderungen nachgewiesen: Hypertrophie und Hyperplasie der Pneumocyten vom Typ 2, Anhaufung intraalveolarer Makrophagen und Verdickung der Alveolarwande.

Es wurden die Wirkungen von Chlorpropamid, Glibenclamid und Tolbutamid auf die Nieren wasserbelasteter normaler und diabetischer Ratten untersucht.

The surface membrane characteristics of canine peripheral blood lymphocytes were investigated using erythrocyte (E) and erythrocyte antibody complement (EAC) rosette assays and immunofluorescent staining techniques. Canine thymus-derived lymphocytes formed nonimmune E rosettes with human and guinea pig erythrocytes at approximately the same percentages (mean percentage 36.3 and 32.4, respectively). Rosettes did not form with erythrocytes from seven other animal species. Cell surface immunoglobulins were demonstrable in a small percentage (4%) of the E rosette-forming lymphocyte population. Fragments of human erythrocytes inhibited E rosette formation by intact human red cells, but did not result in a significant decrease in rosette formation by intact guinea pig erythrocytes; likewise, guinea pig fragments had no inhibitory effect on rosette formation by human erythrocytes, demonstrating that separate receptors were required for the two red cell types. EAC rosette formation was not affected by addition of intact or fragmented human and guinea pig erythrocytes. Canine bone marrow-derived lymphocytes were characterized by immunoglobulin on the cell surface and EAC rosette formation. Serial tests of lymphocytes from one dog revealed a wide variation in percentage of cells forming E and EAC rosettes. A close correlation was observed between the immunoglobulin-bearing cells (mean percentage 46.6) and those forming EAC rosettes (mean percentage 49.3).

A low cost computer-based data processing system for a middle-size clinical chemistry laboratory is described. The emphasis is laid on organizing the laboratory work, minimizing the amount of clerical and arithmetic work undertaken by the technicians, and providing positive specimen identification. Details of specimens arriving for analysis are input to the computer, which allocates laboratory numbers and constructs worksheets for the various chemical tests. The results are also input (off-line) to the machine, which brings together results of different tests on one specimen and prints out properly identified reports. The accumulated results are transferred to a large remote computer and stored there on an archives file.

Neste trabalho, sao relatados os resultados da manutencao em laboratorio de duas geracoes de Rothschildia jacobaeae e da tentativa de uma terceira geracao (outono) com resultado totalmente negativo. Sao descritas as lagartas das cinco idades com detalhes de peso observados especialmente na quinta idade. ABSTRACT In this paper, the results of the development and fertilization in the laboratory of three generations of Rothschildia jacobaeae are reported. Five instars are described; data on the weights, mainly of lhe fifth instar larvae, are given. RESUME Les auteurs presentent dans cet article los resultats de l'entretien dans le laboratoire de deux lignees de R. jacobaeae et de l’essai d’une autre (obtenue en outomne) dont lo resultat a ete tout a fait negatif. Ils decrivent egalement les chenilles des cinq stades en indiquant leur poids observes, plus particulierement au cours de la derniere periode.