Effects of Adsorbed Polyaniline on Redox Process on MoO3 Surface

The effects exhibited by adsorbed conducting polyaniline on the redox process on a molybdenum oxide surface were studied. Thermogravimetric results indicate a 4% polyaniline deposition. Cyclic voltammograms of the adsorbed polymer on MoO3 show that polyaniline exerts remarkable effects on the molybdenum blue oxidation-reduction process, with oxidation and reduction potentials of 0.33 and 0.18 V, respectively. This effect strongly enhances the electrode response, and can be used as an important tool in qualitative and/or quantitative determinations of molybdenum in solution as well as in any substrate. Copyright 1999 Academic Press.     

奥尔堡PBL模式对提升有机波谱分析教学效果的启示

概述了有机波谱分析课程教学中存在的主要问题，介绍了奥尔堡PBL模式的主要特点和优势，分析了将奥尔堡PBL模式用于有机波谱分析课程教学的必要性和可行性，并从课时分配、教学内容、教学方式和考核方式等4方面提出了教学改革方案，旨在提高教学效果。     

Synthesis of heterocyclic thiosulfonates

[formula: see text] A simple synthesis of heterocyclic thiosulfonates containing indole, indoline, benzoimidazole, and quinoxaline rings is described. The synthesis of these thiosulfonates involves the preparation of the appropriately substituted thiols followed by sulfonylation to give thiosulfonates. The corresponding thiols were prepared in a simple and efficient manner by using a thiocyanation reaction either prior to heterocycle ring formation or after heterocycle ring formation. These thiosulfonates were coupled successfully to the 5,6-dihydropyran-2-one ring to give products that showed excellent HIV protease activity.     

Wavelength conversion in GaAs micro-ring resonators

Tightly confined, low-loss waveguides in highly nonlinear materials permit nonlinear optical interactions to occur over much shorter distances than do fibers. The nonlinear interactions are further enhanced in resonators. Both theory and experiment of enhanced four-wave mixing in micro-ring resonators are presented that can be used for many applications. A conversion efficiency of 14% achievable with only 10-mW peak pump power is predicted under realizable conditions. The experiment, the first one to the authors' knowledge in nonlinear optics performed in micro-rings, shows, even in a lossy GaAs/AlGaAs ring, a 26-dB improvement in the conversion efficiency compared with that of an equivalent straight waveguide, in agreement with theory.     

Filter synthesis for periodically coupled microring resonators

The theory of filter synthesis using periodically coupled microring resonators is developed as a means to overcome the fabrication sensitivities inherent in conventional higher-order filters, while still achieving desirable spectral characteristics. Each resonator in the array can compensate for deficiencies in any of the others. These filters exhibit a boxlike shape and very high extinction ratios.     

Thermal Analysis in Examinations of Metallurgical Materials Obtained From Iron-bearing Fines

This paper present results of research performed on briquettes containing iron oxides with the aiming of establishing a relationship between their chemical and phase compositions. Briquettes obtained from industrial in-plant fines waste were subjected to experimental tests involving simulation of the temperature conditions and the redox potential of a gas phase, characteristic of both the top and central parts of a blast furnace. The results of the analysis allowed conclusions concerning the use of briquettes as a blast furnace charge component. This revised version was published online in July 2006 with corrections to the Cover Date.     

A Continuous-Wave Ho：YA103 Laser with Output 8.5 W Pumped by a 1.91μm Laser at Room Temperature

A cw high efficient Ho：YAI03 laser pumped by 1.91 μm diode-pumped Tm：YLF laser at room temperature is realized. The maximum output power reaches 8.5 W when the incident pump power is 15.6 W. The slope efficiency is 63.7%, and the Tm：YLF to Ho：YAP optical conversion efficiency is 54.5%. The laser wavelength is 2118.3nm when the transmission of output coupler is 30%. The beam quality factor is M2 -1.39 measured by the traveling knife-edge method.     

Picosecond pulses produced by synchronously pumped cavity dumped pyridine 1 dye laser

Nearly transform limited picosecond pulses have been produced with a synchronously pumped cavity dumped dye laser using pyridine 1 laser dye. The observed tuning range of 678 to 790 nm extends the usefulness of cavity dumped systems pumped by mode locked argon ion lasers. Pulse autocorrelation widths as short as 3.85 ps were observed. The effects of the variation of bandwidth and net gain on autocorrelation shape and width are presented. Observed autocorrelation traces are compared to transform limited autocorrelation traces calculated from the corresponding power spectra.