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The temperature dependence of elastic‐diffracted intensities for polycrystalline Al films has been investigated at 296° and 77°K as a function of crystal thickness in the range 600–2500 A. A quantitative agreement is found with the predictions of the BJR two‐beam approximation of the dynamical theory. This agreement, however, appears to be best for Al in a range of thickness below the anomalous absorption distance or where kinematical theory should apply.

The structure of Ge films evaporated by several methods onto room temperature substrates of NaCl and films which have been ion implanted with 3 × 1015, 30 to 40 ke V Ge74 has been investigated via a scanning electron diffraction instrument with electron energy filtering. The radial distribution functions of all films are very similar and exhibit strong correlation peaks at 2.45, 4.00, and (4.85 ± 0.075) A with coordinations of 4, 12, and ≈ 7, respectively. The remaining major peaks for higher r deviate substantially from the diamond cubic form of Ge. From the RDF analysis a density ratio ϱ0/ϱcryst of 0.86 to 0.95 is determined. Thermal anneal experiments showed that the films may be annealed to a density of ≈0.97 of crystalline density without crystallization. Amorphous films which have been ion implanted with the same energy and dose as the polycrystalline films show a considerable concentration of pores and voids of a maximum diameter of 100 A. The RDF, however, is identical to the as-deposited film with the exception of some changes in the correlation for r greater than 11 A. Die Struktur dunner Ge-Schichten, die auf verschiedene Arten auf NaCl-Trager bei Zimmertemperatur aufgedampft wurden und die mit 3 × 1015 (30 bis 40 keV) Ge74-Ionen beschossen wurden, wird mit Hilfe einer Abtastelektronenbeugungsanlage mit Elektronenenergiefilter untersucht. Die Atomverteilungskurven (RDF) aller Schichten sind sich sehr ahnlich und zeigen starke Korrelationsmaxima bei 2,45; 4,00 und (4,85 ± 0,075) A mit Koordinationszahlen von 4, 12 bzw. ≈7. Die ubrigen Hauptmaxima fur grosere r unterscheiden sich bedeutend von denen des (Diamant)kubischen Ge. Mit Hilfe der Atomverteilungsanalyse (RDF) wird das Dichteverhaltnis (ϱ0/ϱkrist) zu 0,86 bis 0,95 ermittelt. Heizversuche zeigten, das die Schichten ohne Kristallbildung bis zur Kristalldichte von 0,97 getempert werden konnten. Amorphe Schichten, die mit Ionen gleicher Energie und Dosis wie polykristalline Schichten beschossen wurden, enthielten eine hohe Konzentration von Poren und Hohlraumen mit maximalem Durchmesser von 100 A. Die Atomverteilungskurven (RDF) dieser Schichten und der aufgedampften sind bis auf kleine Anderungen in den Korrelationsmaxima fur r groser als 11 A identisch.

The kept collection of incunabula is not uniform in terms of their origins. Although this is a small collection, in many ways it is interesting concerning both authors, areas of their knowledge, notes of origin or their binding. The library has in total twelve bibliographical positions in ten volumes. They are the work of workshops located in four urban centres: Venice, Cologne, Strasbourg and Augsburg. All of the collection of books are concentrated around four major groups: Scripture, Theology, law and philosophy. The authors of those works were the most prominent representatives of medieval science. Part of the incunabula’s cover are from the period of the book’s print (turn of fifteenth and sixteenth century), part of them are from the later period.

Entries made in the Płock magistrates’ book between 1489 and 1517 mention a total of nineteen clergymen, who were primarily associated with the local church environment. Evident in these entries is the clergy’s involvement as arbitrators in legal disputes. They are also mentioned as executors of testaments or recipients of legacies, parties in deeds of sale, holders of deposits, and prudent stewards of church property. Entries in the Płock magistrates’ book involving the local clergy seem to indicate that that the representatives of the Catholic Church were greatly trusted and esteemed by the local community.

Several methods of P i estimation commonly used in research on PP-hydrolase activity of various proteins were found inconvenient due to the ability of the excess of PP to decompose during the development of color in strongly acidic media. One of the procedures described by Delsal and Manhouri (20) with Metol as the reducing agent in mild acidic medium was found to be the method of choice for the estimation of weak PP-hydrolase activities. Another Delsal and Manhouri procedure (22) was found useful for the estimation of total P i + PP.

A scanning electron diffraction attachment providing for energy analysis of the scattered electrons has been constructed for use in conjunction with a J.E.M. 6AS electron microscope. This attachment permits the direct recording of diffracted electron intensities as a function of angle with an accuracy of ±0.1%. The attachment can be operated to exclude all but the elastically diffracted electrons, or, alternatively, to detect electrons with a measurable amount of energy loss. The electrostatic energy analyzer has an energy cutoff of better than 1.1 eV out of 100 keV. The angular resolution of the instrument is presently 2.2×10−4 rad, with minimum detectable electron intensity of 10−14 A. The instrument performance is demonstrated by studying the effect of inelastic scattering in the diffraction pattern of aluminum, and by recording the plasma loss spectrum of aluminum. The filtered profiles have narrower peaks than the unfiltered ones and better peak resolution, and the contrast between peaks and background is enhanced. At low values of the scattering vector where the inelastic background is very intense, its removal reveals diffraction effects which otherwise would have been invisible. The attachment does not interfere with the conventional plate microscopy and diffraction, and provides, thereby, a method of energy analyzing the direct microscope image as well.

We present electron diffraction data from amorphous silicon which cannot be reconciled with the intensity profiles derived from small-crystallite models based on the diamond structure. Our diffraction patterns do reveal a pronounced low-angle scattering which anneals out on progressive heating and is indicative of actual void spaces, or regions of distinctly deficient density, in the films. These regions may be responsible for the recent observations of Brodsky and Title on surface states within the bulk of amorphous Si.

Dielectric measurements in microwave bands are used to throw light on the structure of 1:1 complexes of s-trinitrobenzene and related molecules with aniline, anthracne and p-aminoazobenzene. Monocrystalline and polycrystalline complexes show significant differences.

The structure of as deposited thin films of SiO2 and as deposited, as well as heated Si, Ge, and several Ge–Te alloys, has been investigated by transmission electron microscopy and electron diffraction. Using high resolution dark field microscopy it is shown that the structure of all the amorphous specimens investigated comprised of coherently scattering regions 10 to 20 A in size. The coherently scattering regions are retained until crystallization in the Si, Ge, and GeTe films. In the case of tellurium-rich Ge–Te alloys, the coherently scattering regions are found to disappear and reappear with temperature cycling. On the basis of the experimental evidence, it is suggested that the conventional microcrystalline model is not a valid description of amorphous materials. Die Strukturen dunner Schichten von SiO2 und aufgedampfter sowie getemperter Schichten von Si, Ge und einigen Ge–Te-Legierungen wurden mittels Elektronenmikroskopie und Elektronenbeugung untersucht. An Hand von Dunkelfeldmikroskopie hoher Auflosung wird gezeigt, das alle untersuchten Proben koharent streuende Bereiche von 10 bis 20 A enthalten. Diese koharent streuenden Bereiche werden bis zur Kristallisation des Si, Ge und der Verbindung GeTe beibehalten; in Ge–Te-Mischungen, die reich an Te sind, sind sie aber umkehrbar von der Temperatur abhangig. Auf Grund dieser experimentellen Ergebnisse wird angenommen, das das konventionelle mikrokristalline Modell nicht geeignet ist, um den amorphen Zustand zu beschreiben.