Quantum Computation Violates Mirror Symmetry

The CNOT gate is asymmetric with respect to parity. It requires interaction with the environment, and cannot be realized as an isolated quantum collision.     

Characteristics and lacquer adhesion on dip and CDC chromium passivated tinplate

Chromium passivation and lacquering are typically used to improve the corrosion resistance of tinplate in packed food. In this work, the nature of the chromium passivation layer formed during dip or CDC passivation treatments, as a function of operational parameters, and its influence on lacquer adhesion, was investigated using electrochemical polarisation, XPS, Auger and lacquer peel-off tests. It was found that dip passivated tinplate provide the best lacquer adhesion, and that the adhesion on CDC treated tinplate could be improved by buffering or lowering the pH of the chromium (VI) solution.     

Steel Girder Design per AASHTO LRFD Specifications (Part 2)

This is the second of two companion papers discussing and illustrating the AASHTO LRFD Bridge Design Specifications for the design of steel girders subject to flexure and shear. In the first paper, notation was introduced that allows reformulation of the AASHTO design equations in a more convenient format and the design of steel I-girders in flexure was presented. The second paper addresses design of box girders for flexure and design of box and I-girders for shear. The design approach is illustrated by two detailed example problems.     

Temperature and field-dependence of hopping conduction in organic semiconductors

Electrical characteristics of the hopping transport in organic semiconductors are studied theoretically. Based on percolation theory of hopping between localized states, an analytical mobility model is obtained. This model is applied to the analysis of both the electric field dependence and the temperature dependence of the mobility. The results agree quantitatively with recent experimental data.     

Scalability of Web-based electronic commerce systems

In a Web-based electronic commerce system, users browse product information offered by an online store and submit requests to purchase selected items. From the user's perspective, response time is a factor that could impact the acceptability of electronic commerce. This article is concerned with system architectures for online stores. Emphasis is placed on techniques to improve a system's capacity to support more users without suffering a noticeable degradation in response time performance. Such techniques have been investigated as part of a Canadian Institute for Telecommunications Research major project entitled Enabling Technology for Electronic Commerce Applications, developed in close collaboration with the IBM/sup /spl reg// Centre for Advanced Studies. The basic architecture of a Web-based electronic commerce system is first described along with the types of data that need to be managed. Next, an overview of existing techniques for improving system capacity is presented. Finally, highlights of research results obtained as part of the CITR electronic commerce major project are discussed.     

Application of enzymes in anaerobic digestion.

Owing to the very low economic value of brewer's spent grains, its utilisation for biogas production is very promising. The hydrolysis of ligno-cellulose is the rate limiting step in anaerobic digestion. Enzymatic pre-treatment promotes the hydrolysis of ligno-cellulose, breaking it down to lower molecular weight substances which are ready to be utilised by the bacteria. A cheap raw multi-enzyme produced by a solid state fermentation (SSF) process is a good substitute for expensive conventional enzyme. The SSF enzyme application to spent grain has been investigated by carrying out enzymatic solubility tests, hydrolytic experiments and two-step anaerobic fermentation of spent grain. Gas chromatograph analysis was conducted to quantify fatty acids concentrations, while CH(4), CO(2), O(2), H(2) and H(2)S were measured to determine biogas quality by means of a gas analyser. DS, oDS, pH were also measured to analyse the anaerobic digestion. The result shows that enzyme application promotes the hydrolysis of ligno-cellulose, indicated by higher enzymatic solubility and fatty acid concentration in a hydrolytic bioreactor. Moreover, biogas production is also increased. The quality of the gases produced is also enhanced. Since the anaerobic digestion can be operated in a stable performance, it can also be concluded that SSF enzyme is compatible with anaerobic digestion.     

New challenges in the field of spatial planning: landscapes

The European Landscape Convention (ELC) highlights the landscape as an holistic concept, which is important for individual and social well being and for quality of life. Landscape questions tend today to fall between the responsibilities of different sectors of society. The implications of the Convention for giving ‘landscape’ a higher status in spatial planning are discussed. Important challenges for planning that need to be focused from a landscape approach are discussed: the growing urbanization; the development and new roles of the urban fringe areas; new infrastructure landscapes; the mental landscapes of tomorrow; an holistic approach to landscape ecological planning and environmental policies and the need for co‐ordination of European planning issues that concern landscapes. Planning for good landscape qualities is not a new issue; many landscape architects and landscape planners have worked in the spirit of the ELC for decades. The importance of educating landscape architects and planners with an holistic approach is particularly addressed. Efforts for a more integrated landscape education, such as the European network LE:NOTRE, already exist and contribute to the implementation of the ELC.     

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