Preparation of ZnSe light-emitting diodes by metalorganic chemical vapor deposition using trisdimethylaminoarsine as a p-type doping source

Trisdimethylaminoarsine was used in atmospheric-pressure metalorganic chemical vapor deposition growth of ZnSe on GaAs. The metalorganic precursors employed for ZnSe growth were diethylzinc and diethylselenide, and ethyliodide was used as then-type dopant. P-on-n light emitting diode (LED) structures were prepared, and molecular beam epitaxially deposited HgTe layers were used as ohmic contacts to the p-type ZnSe. Blue LEDs were fabricated on p-on-n samples. Preliminary LED data and the material characterization data are presented.     

An interlaboratory trial of the effects of reducing liquor to cloth ratio in the ISO 105-C08 test on repeatability and reproducibility

An international ring test has been carried out to assess the repeatability and reproducibility of the ISO 105-C08 test, modified to employ a liquor to cloth ratio of 20;1 in place of the current specification of 50;1. The results, from ten laboratories located in six countries, indicate that no adverse consequences are to be expected from reducing the liquor ratio, with the statistical variability obtained being well within the norm for this type of wash fastness test. It is therefore recommended that the standard be modified to allow the test to be conducted at a range of liquor to cloth ratios. The work in this paper was initiated by the TCI/81 committee and is sponsored by the Society's Technical Coordination Committee.     

3M: a user modelling interface of an expert system for X-ray topographic image interpretation

This paper discusses user modelling techniques and presents the design and implementation of the 3M user modelling interface of INTEREX. INTEREX is an expert system for X-ray topographic image interpretation which assists its users in identifying and analysing a number of defects that can occur in high-quality crystals. 3M consists of a monitor, a model and a modifier. It is used to adapt the consultation route and the explanations provided by INTEREX to three categories of users. It demonstrates the use-of an implicit, individual, dynamic and long-term user model to enable an expert system to accommodate users with different levels of expertise.     

The MUSiC performance measurement method

. This paper reports a method for measuring usability in terms of task performance-achievement of frequent and critical task goals by particular users in a context simulating the work environment. The terms usability and quality in use are defined in international standards as the effectiveness, efficiency and satisfaction with which goals are achieved in a specific context of use. The performance measurement method gives measures which, in combination with measures of satisfaction, operationalize these definitions. User performance is specified and assessed by measures including task effectiveness (the quantity and quality of task performance) and User efficiency (effectiveness divided by tasktime). Measures are obtained with users performing tasks in a context of evaluation which matches the intended context of use. This can also reveal usability problems which may not become evident if the evaluator interacts with the user. The method is supported by tools which make it practical in commercial timescales. The method has been widely applied in industry, and can be adapted for use early in design, and to evaluate non-computer products and the performance of small work groups.     

Wafer-level photocatalytic water splitting on GaN nanowire arrays grown by molecular beam epitaxy

We report on the achievement of wafer-level photocatalytic overall water splitting on GaN nanowires grown by molecular beam epitaxy with the incorporation of Rh/Cr(2)O(3) core-shell nanostructures acting as cocatalysts, through which H(2) evolution is promoted by the noble metal core (Rh) while the water forming back reaction over Rh is effectively prevented by the Cr(2)O(3) shell O(2) diffusion barrier. The decomposition of pure water into H(2) and O(2) by GaN nanowires is confirmed to be a highly stable photocatalytic process, with the turnover number per unit time well exceeding the value of any previously reported GaN powder samples.     

A sermon of sorts in three plus parts.

Based on his presidential address delivered at the annual meeting of the American Psychological Association (APA) in 1982, the author urges APA's commitment to 3 tasks: (1) a continuing study of the intellectual and social influences, inside and outside psychology, that have shaped and continue to shape its directions, (2) an active program to increase the public's understanding of what psychology is and what psychologists do, and (3) a formal involvement at the level of national policy in issues where psychological knowledge and skills are relevant. (70 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)