Synthesis and characterization of water-soluble diazonium salts as contrast-enhancement materials

Water soluble aromatic diazonium double salts, p-diazodiphenylamine chloride zinc chloride (DZS-1) and p-diazoanisol chloride zinc chloride (DZS-2), have been evaluated as photobleachable dyes for contrast enhancement lithography. After testing the bleaching characteristics, aqueous solutions of DZS-1 and poly(vinyl alcohol) were used as a contrast enhancement material. Thermal stability, resist contrast, exposure parameters and other bleaching characteristics of the photobleachable membranes were investigated. A. commercial i-line photoresist was used to evaluate the contrast ratio of the DZS-1/PVA CEL layer. The contrast ratio obtained in this investigation is 1.67.     

Denitrifying kinetics involving the distributed ratio of reductases

A suspended-growth batch reactor was used to denitrify synthetic wastewater containing various proportions of nitrate and nitrite. A competitive phenomenon between nitrate- and nitrite-reductase was studied utilizing various proportions of nitrate and nitrite in an anaerobic environment with a temperature of 30°C and methanol as carbon source. By using a non-linear regression technique, biokinetic constants of the maximum specific reduction rates of nitrate and nitrite (k₁, k₂) and the Monod half-saturation coefficients of nitrate and nitrite (K_s1, K_s2) for the proposed two-step denitrifying kinetics were 1·29 day^?1, 0·89 day^?1 and 14·3 mg NO-N dm^?3, 10.9 mg NO-N dm^?3, respectively. The result obtained from a series of chemostat studies indicated the Monod-type kinetic model was more accurate when the distributed ratio of nitrate- and nitrite-reductase in the proposed two-step denitrifying kinetics was taken into account.     

Ambient interaction and situational influence: case studies in public sites

Abstract

An audience's direct physical intervention is widely believed to be instrumental in the field of interactive art. However, this long established expectation faces new challenges through the increasing accessibility of a growing diversity of interactive technologies and ubiquitous smart media. Such innovations are often fully integrated components of interactive public artworks, many of which do not directly involve audiences or individuals as key agents in the functional or aesthetic realisation of the work. Based on three case studies of interactive artworks in public places, this article identifies an important characteristic of interactivity in interactive art, through the largely unexplored concept of “Ambient Interaction” in which artworks are embodied and enacted through environmental conditions and situational influences rather than exclusively through people's intentional and direct physical engagement.     

Size exclusion chromatography to characterize DOC removal in drinking water treatment

A full-scale (110 ML/d) potable water treatment plant (WTP) based on the MIEX process, an innovative new process based on a strong base anion-exchange resin with magnetic properties, has been operating in Perth Western Australia since 2001. This plant has been configured so that a combined MIEX-coagulation (MIEX-C) process can be operated in parallel with a conventional enhanced coagulation (EC) process, allowing comparison of the performance of the two processes. Here, we report the use of size exclusion chromatography (SEC) to compare the removal of different apparent molecular weight (AMW) fractions of DOC by the two processes. Water was sampled from five key locations within the WTP, and SEC was carried out using three different on-line detector systems, DOC-specific detection, UV absorbance detection at lambda = 254 nm, and fluorescence detection (lambda(ex) = 282 nm; lambda(em) = 353 nm). This approach provided information on the chemical nature of the DOC comprising the various AMW fractions. The study showed that the MIEX-C process outperformed the EC process with greater removal of DOC in each of the eight separate AMW fractions identified. While EC preferentially removed the fractions of highest AMW, and those exhibiting the greatest aromatic (humic) character, MIEX-C removed DOC across all AMW fractions and did not appear to discriminate as strongly on the basis of differences in aromatic character or AMW. The results demonstrate the benefits of combining these complementary treatment processes. The study also demonstrates the utility of SEC coupled with multiple detection systems in determining the characteristics of various AMW components of DOC.     

Fabrication of a full-size mock-up for inboard 10° section of ITER vacuum vessel thermal shield

A full-scale mock-up of VVTS inboard section was made in order to validate its manufacturing processes before manufacturing the vacuum vessel thermal shield (VVTS) for ITER tokamak. VVTS inboard 10° section consists of 20 mm shells on which cooling tubes are welded and flange joints that connect adjacent thermal shield sectors. The whole VVTS inboard is divided into two by bisectional flange joint located at the center. All the manufacturing processes except silver coating were tested and verified in the fabrication of mock-up. For the forming and the welding, pre-qualification tests were conducted to find proper process conditions. Shell thickness change was measured after bending, forming and buffing processes. Shell distortion was adjusted after the welding. Welding was validated by non-destructive examination. Bisectional flange joint was successfully assembled by inserting pins and tightening with bolt/nut. Bolt hole margin of 2 mm for sector flange was revealed to be sufficient by successful sector assembly of upper and lower parts of mock-up. Handling jig was found to be essential because the inboard section was flexible. Dimensional inspection of the fabricated mock-up was performed with a 3D laser scanner.     

Pressure drop on water accumulation distribution for a micro PEM fuel cell with different flow field plates

Time-dependent measurements of pressure drop in different flow fields on the cathode of a PEM fuel cell with different operating conditions of mass flow rates and cell temperatures on water accumulation were conducted. The results show that, among four flow fields studied herein, the interdigitated flow channel has the biggest pressure drop as well as the largest water accumulation at an early phase (?30 min) compared to those of the other three channels. In addition, the more water produced, the bigger the pressure drop that occurs. Similarly, the effects of mass flow rates at a fixed cell temperature were also examined and discussed.     

Fracture analysis of interfacial crack by global-local finite element

An eigenfunction expansion is used to formulate the global element on the crack tip. The global-local finite element method employs both conventional finite element and classical Rayleigh-Ritz kinematic approach. The hybrid Ritz method not only preserves the finite element modelling capability but adds the advantage of using prior information regarding the anticipate behaviour of the particular problem. Thus, it is able to achieve better accuracy with fewer elements in comparison with conventional finite element. Several examples relative to crack problems are presented to demonstrate the global-local finite element method.     

A secure multicast protocol for the internet's multicast backbone

In this paper we propose a secure and efficient multicast protocol where the key management is distributed to local groups. The proposed protocol takes advantage of MBone topology to maintain scalability and efficiency at the same time. Copyright © 2001 John Wiley & Sons, Ltd.