Journal of Applied Crystallography

Volume 31, Part 4 (August 1998)


Cover illustration Cover illustration: Powder diffraction pattern of LaB6 obtained using a 200 x 400 mm flat imaging plate mounted at an angle of 45 degrees with the incoming X-ray beam. Experimental conditions: lambda = 0.8884 angstroms, D0 = 104 mm, exposure time 60 s. Courtesy of Poul Norby.

research papers



pdf version buy article online

J. Appl. Cryst. (1998). 31, 515-522    [doi:10.1107/S0021889897010571]

New Crystallization Systems Envisioned for Microgravity Studies

T. L. Bray, L. J. Kim, R. P. Askew, M. D. Harrington, W. M. Rosenblum, W. W. Wilson and L. J. DeLucas

Synopsis: Custom instrumental systems utilizing two methods, vapour diffusion and temperature, have been developed for use in crystallizing proteins. These systems offer dynamic control of the crystallization process, resulting in dramatically improved crystallization results over results obtained with traditional methods.



pdf version buy article online

J. Appl. Cryst. (1998). 31, 523-532    [doi:10.1107/S0021889897015045]

An Algorithm for Automatic Mosaic Spread Analysis of a Protein Crystal

J.-L. Ferrer and M. Roth

Synopsis: This paper presents the program MOSAICITY, dedicated to the analysis of rocking curves and the evaluation of mosaic spread. The program includes a peak search, the integration of reflections and the refinement of some parameters involved in a new analytical model of the oscillation range versus the beam and crystal characteristics.



pdf version buy article online

J. Appl. Cryst. (1998). 31, 533-543    [doi:10.1107/S0021889897015422]

A Small-Angle X-ray Scattering Apparatus for Studying Biological Macromolecules in Solution

Z. Bu, A. Perlo, G. E. Johnson, G. Olack, D. M. Engelman and H. W. Wyckoff

Synopsis: The design features of a laboratory-based small-angle X-ray scattering system for studying biological macromolecules in solution are described.



pdf version buy article online

J. Appl. Cryst. (1998). 31, 544-553    [doi:10.1107/S002188989701618X]

Electron Crystallography of Small Organic Molecules: Criteria for Data Collection and Strategies for Structure Solution

D. L. Dorset, M. P. McCourt, G. Li and I. G. Voigt-Martin

Synopsis: For ab initio electron crystallographic structure analyses of small organics, special care must be taken in sample crystallization in order to record useful selected-area diffraction intensities. However, if the reciprocal lattice is incompletely sampled, con- strained energy minimization may be superior to direct methods for structure determination.



pdf version buy article online

J. Appl. Cryst. (1998). 31, 554-558    [doi:10.1107/S0021889897019559]

Dislocations and Grain Size in Electrodeposited Nanocrystalline Ni Determined by the Modified Williamson-Hall and Warren-Averbach Procedures

T. Ungár, Á. Révész and A. Borbély

Synopsis: The root-mean-square-strains were interpreted by the presence of dislocations in nanocrystalline Ni taking into account aniso- tropic dislocation contrast. Due to proper deconvolution of strain broadening, grain and coherent domain sizes were obtained in agreement with TEM.



pdf version buy article online

J. Appl. Cryst. (1998). 31, 559-569    [doi:10.1107/S0021889897019626]

Decasil (SiO2): Multiple Twinning and Two-Dimensional Disorder

P. Daniels

Synopsis: Diffuse X-ray scattering observed for this porous SiO2 polymorph is explained by a model based on submicroscopic twinning. For its analysis a simple recursive method is developed.



pdf version buy article online

J. Appl. Cryst. (1998). 31, 570-573    [doi:10.1107/S0021889897020281]

X-ray Multiple-Beam Analysis in High-Resolution Diffractometry of III-V Heterostructures

D. Korytár, C. Ferrari and Z. Bochnícek

Synopsis: This paper presents an analysis of the information obtainable by an X-ray multiple-beam diffractometry technique applied to the evaluation of III-V heterostructures.



pdf version buy article online

J. Appl. Cryst. (1998). 31, 574-582    [doi:10.1107/S0021889898000375]

Analysis of the Propagation Modes of Acoustic Waves in Piezoelectric Devices in Synchrotron White-Beam Topographs by Means of Simulations

Y. Epelboin, J. Détaint and B. Capelle

Synopsis: Ultra-acoustic waves in piezoelectric devices have been studied by means of white beam X-ray topography. Simulations allow the confirmation of a theoretical model.



pdf version buy article online

J. Appl. Cryst. (1998). 31, 583-588    [doi:10.1107/S0021889898001356]

A Test of the Suitability of CCD Area Detectors for Accurate Electron-Density Studies

P. Macchi, D. M. Proserpio, A. Sironi, R. Soave and R. Destro

Synopsis: The performance of CCD area detectors in charge-density analysis has been tested. The positive and encouraging results allow us to state that electron-distribution studies of large organic or organometallic compounds will be much more easily achievable using this kind of detector.



pdf version buy article online

J. Appl. Cryst. (1998). 31, 589-593    [doi:10.1107/S0021889898001071]

X-ray Fine Structure Investigation of Germanium Nanoclusters

J. Bläsing, P. Kohlert, M. Zacharias and P. Veit

Synopsis: Starting from amorphous SixGeyOz films, we have investigated the development of germanium nanoclusters in relation to sputtering and annealing conditions.



pdf version buy article online

J. Appl. Cryst. (1998). 31, 594-599    [doi:10.1107/S0021889898002192]

Simulation of Small-Angle X-ray Scattering from Single-Particle Systems

B. C. McAlister and B. P. Grady

Synopsis: A new theoretical approach is presented to model small-angle scattering curves for a single centrosymmetric particle. This method can quickly and reliably simulate the scattering from particles whose orientations or geometries are such that analytical evaluation is very difficult or impossible.



pdf version buy article online

J. Appl. Cryst. (1998). 31, 600-608    [doi:10.1107/S0021889898002209]

Direct Structure Analysis of Small-Angle Scattering Data from Polydisperse Colloidal Particles

R. Mittelbach and O. Glatter

Synopsis: The numerical evaluation method presented in this paper allows the direct determination of the internal structure of polydisperse colloidal particles from small-angle scattering data. The result is a continuous density profile and a polydispersity parameter.



pdf version buy article online

J. Appl. Cryst. (1998). 31, 609-619    [doi:10.1107/S0021889898002313]

IFO: a Program for Image-Reconstruction-Type Calculation of Atomic Distribution Functions for Disordered Materials

V. Petkov and R. Danev

Synopsis: IFO is a computer program that transforms experimental structure factors for disordered materials to atomic distribution functions by employing an image-reconstruction-type technique.



pdf version buy article online

J. Appl. Cryst. (1998). 31, 620-624    [doi:10.1107/S0021889898002672]

Absorption Correction for Annular Cylindrical Samples in Powder Neutron Diffraction

D. Schmitt and B. Ouladdiaf

Synopsis: Numerical calculations of neutron absorption coefficients for annular cylindrical samples are reported.



pdf version buy article online

J. Appl. Cryst. (1998). 31, 625-633    [doi:10.1107/S0021889898002684]

Effect of Thermal Diffuse Scattering in Triple-Crystal Diffractometry with High-Energy Synchrotron Radiation

T. Schmidt, D. Woo, S. Keitel, J. R. Schneider, U. Lambert and W. Zulehner

Synopsis: A procedure to correct for thermal diffuse scattering in triple-crystal diffractometry with high-energy synchrotron radiation is presented.



pdf version buy article online

J. Appl. Cryst. (1998). 31, 634-637    [doi:10.1107/S0021889898003008]

Modulated-Crystal Model for the Twelvefold Quasicrystal Ta62Te38

M. Uchida and S. Horiuchi

Synopsis: A transmission electron microscopy study reveals that the twelvefold quasicrystal Ta62Te38 is an incommensurate crystal. The modulation is considered to be due to the rearrangement of atomic vacancies as a response to the occurrence of charge-density waves.


cryocrystallography papers



pdf version buy article online

J. Appl. Cryst. (1998). 31, 638-640    [doi:10.1107/S0021889898002210]

A eucentric goniometer head sliding on an extended removable arc modified for use in cryocrystallography

A. Litt, J. G. Arnez, B. P. Klaholz, A. Mitschler and D. Moras

Synopsis: A goniometer head sliding on a large removable arc which retains eucentricity and allows any position between coaxial and vertical orientations relative to a horizontal spindle axis was designed for crystal handling at cryotemperatures.


laboratory notes



pdf version buy article online

J. Appl. Cryst. (1998). 31, 641-643    [doi:10.1107/S0021889898001368]

A temperature-gradient apparatus for the optical investigation of phase transitions in polarized light

O. Müller and M. Mühlberg

Synopsis: A versatile apparatus for optical investigations of phase transitions in platelike crystalline samples in adjustable temperature gradients is described. Some details of its application to investigating phase transitions in lead phosphate and barium calcium titanate are also given.



pdf version buy article online

J. Appl. Cryst. (1998). 31, 644-645    [doi:10.1107/S0021889898002507]

An automatic Bio-Beads-supplying device for two-dimensional crystallization of membrane proteins

K. Nakazato and Y. Inoue

Synopsis: A simple device has been developed for the automatic supply of hydrophobic resin beads simultaneously to many sample solutions. The device enables the programmed removal of various types of nonionic detergents often used for two-dimensional crystallization of membrane proteins.


computer program abstracts



pdf version buy article online

J. Appl. Cryst. (1998). 31, 646    [doi:10.1107/S0021889898005524]

WYCKSPLIT: a computer program for determination of the relations of Wyckoff positions for a group-subgroup pair

E. Kroumova, J. M. Perez-Mato and M. I. Aroyo

Synopsis: The program WYCKSPLIT determines the relations of the Wyckoff positions for a group-subgroup pair of space groups.


notes and news



pdf version free

J. Appl. Cryst. (1998). 31, 646    [doi:10.1107/S0021889898099002]

Notes and News


Copyright © International Union of Crystallography
IUCr Webmaster