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A novel helical coupling microwave antenna is used to generate high-power carbon dioxide laser operation using a cylindrical resonant cavity of 2.45 GHz. Laser experiments are conducted using a system of swirling fast axial gas flow parallel to the beam. Numerical codes that analyze the electric fields and gas flow dynamics are employed to optimize the geometric characteristics of the helical antenna and the gas flow structures. The peak output power and efficiency are achieved and shown to be 1010 W and 15%, respectively, at a gas flow rate of 57 kg/h and a gas pressure of 45 torr.

Experimental analysis of microwave discharges from a TM010-mode microwave excited high power CO2 laser with cylindrical resonant microwave cavity shows that the resonant cavity enables high power laser operation and homogeneous microwave discharges. The laser has an efficiency of 147 and an output of 259 W. Data from experimental measurements are comparable to the electric field evaluations inside the microwave cavity that contains a dielectric tube.

Research has been conducted on the nucleophilic reagents vinyloxiranes. The reactions of the caronyl compounds with the allylic indium reagents derived from the vinyloxiranes have been investigated and the results indicate the dependence of the regio- and stereoselectivity on the reaction temperature, solvents, carbonyl compounds and the vinyloxirane substitution pattern.

Synthesis of thermally stable rotamers of bicyclic dioxetanes bearing 6-hydroxynaphthalen-1-yl, 3-hydroxynaphthalen-1-yl, and 5-hydroxy-2-methylphenyl groups are described. The significant differences observed in the chemiluminescence spectra of the rotamers are discussed from the viewpoint of a chemiexcitation mechanism for CTID (charge-transfer-induced decomposition) of oxidophenyl-substituted dioxetane.

Byline: Xiaodi Huang, Dianhui Wang, Kazuo Misue, Jiro Tanaka, A.S.M. Sajeev Graphs traditionally have many applications in various areas of computer science. Research in graph-based data mining has recently gained a high level of attraction due to its broad range of applications. Examples include XML documents, web logs, web searches and molecular biology. Most of the approaches used in these applications focus on deriving interesting, frequent patterns from given datasets. Two fundamental questions are, however, ignored; that is, how to derive a graph from a set of objects and how to order nodes according to their relations with others in the graph. In this paper, we provide approaches to building a graph from a given set of objects accompanied by their feature vectors, as well as to ranking nodes in the graph. The basic idea of our ranking approach is to quantify the important role of a node as the degree to which it has direct and indirect relationships with other nodes in a graph. A method for visualising graphs with ranking nodes is also presented. The visual examples and applications are provided to demonstrate the effectiveness of our approaches.

Becke's three-parameter hybrid technique has been used to establish the optimized structures and energies of transient species in thermal decomposition of 1,2-dioxetane and 3,3,4,4-tetramethyl-1,2,-dioxetane. Attention is given to the reaction rates of the thermal dissociation and the yield of chemiluminescence.