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[en] The design and metrological characteristics of a photometric gas analyzer for atmospheric sulfur dioxide that is equipped with adsorbing polymer films are considered. It is shown that the device can solve ecological and health safety issues and has small overall dimensions and power consumption.
[en] Sulfur dioxide pollutant was treated in the laboratory with hydrated lime particles having a mean diameter of 9.1 μm in a continuously operating binary fluidized bed reactor also containing inert sand particles with sizes varying from 500 to 590 μm. The influence of temperature (500, 600, 700 and 800 deg. C) on the reaction medium, of the superficial velocity of the gas (0.8, 1.0 and 1.2 m/s), and of the Ca/S molar ratio (1, 2 and 3) on the SO2 removal efficiency were investigated for an inflow gas concentration of 1000 ppm and an initially static bed height of 10.0 cm. The pollutant removal efficiency proved to depend on the temperature and the velocity of the gaseous flow and was strongly influenced by the Ca/S molar ratio. The maximum efficiency of 97.7% was achieved at a temperature of 700 deg. C, a Ca/S ratio of 3 and a velocity of 0.8 m/s. The lime particles' mean residence time was determined by an indirect method, which consisted of integrating the gas concentration curves normalized with respect to time. Based on a calculation of the critical transition velocities, it was concluded that the reactor operated in a bubbling regime under each condition investigated here
[en] This fact sheet explains how Anon, Inc., has developed a novel method of removing photoresist--a light-sensitive material used to produce semiconductor wafers for computers--from the computer manufacturing process at reduced cost and greater efficiency. The new technology is technically superior to existing semiconductor cleaning methods and results in reduced use of hazardous chemicals
[en] It is the purpose of this paper to describe the Air Pollution Project that is being undertaken at the Ecole d'Hygiene of Universite de Montreal. The project is still in its organization phase. However, in the absence of any results, a description of the project with an emphasis on its goals, instrumentation and operational technique might prove interesting and raise comments beneficial to the project. (author)
[en] We present molecular line and 1.4 mm continuum observations toward five massive star-forming regions at arcsecond resolution using the Submillimeter Array. We find that the warm molecular gas surrounding each H II region (as traced by SO2 and OCS) appears to be undergoing bulk rotation. From the molecular line emission and thermal component of the continuum emission, we independently derived gas masses for each region which are consistent with each other. From the free-free component of the continuum emission, we estimate the minimum stellar mass required to power the H II region and find that this mass, when added to the derived gas mass, is a significant fraction of the dynamical mass for that region.
[en] The paper investigates the role of the sulfur-oxidizing bacteria Thiobacillus thiooxidans in pyrite weathering in order to clarify the effects of the bacteria on the dissolution behavior of pyrite and the formation of secondary minerals using Raman spectroscopy and powder X-ray diffraction (XRD) in addition to solution analysis. It was found that T. thiooxidans, when present with the iron-oxidizing bacteria Thiobacillus ferrooxidans, enhanced the dissolution of Fe and S species for pyrite, whereas T. thiooxidans alone did not oxidize pyrite. Enhancement of the consumption of elemental sulfur and regeneration of Fe(II) ions were also observed with T. thiooxidans together with T. ferrooxidans, while this did not occur with T. ferrooxidans alone
[en] Vertical profiles of O_3 and SO_2 concentrations were monitored at the Borden Forest site in southern Ontario, Canada from May 2008 to April 2013. A modified gradient method (MGM) was applied to estimate O_3 and SO_2 dry deposition fluxes using concentration gradients between a level above and a level below the canopy top. The calculated five-year mean (median) dry deposition velocity (V_d) were 0.35 (0.27) and 0.59 (0.54) cm s"−"1, respectively, for O_3 and SO_2. V_d(O_3) exhibited large seasonal variations with the highest monthly mean of 0.68 cm s"−"1 in August and the lowest of 0.09 cm s"−"1 in February. In contrast, seasonal variations of V_d(SO_2) were smaller with monthly means ranging from 0.48 (May) to 0.81 cm s"−"1 (December). The different seasonal variations between O_3 and SO_2 were caused by the enhanced SO_2 uptake by snow surfaces in winter. Diurnal variations showed a peak value of V_d in early morning in summer months for both O_3 and SO_2. Canopy wetness increased the non-stomatal uptake of O_3 while decreasing the stomatal uptake. This also applied to SO_2, but additional factors such as surface acidity also played an important role on the overall uptake. - Highlights: • Application of a modified gradient-method for quantifying dry deposition is demonstrated. • A five-year dry deposition database is developed for O_3 and SO_2 over a mixed forest. • Canopy wetness enhances non-stomatal O_3 uptake while inhibits stomatal uptake. • High surface acidity reduces SO_2 dry deposition. - Capsule: A five-year dataset of O_3 and SO_2 dry deposition velocities was generated from concentration gradient measurement data using a modified gradient method.
[en] We study the dynamical entanglement of vibrations, intramolecular energy transfer and coherence properties in triatomic molecular systems based on discrete self-trapping theory. O3 and SO2 samples are employed as typical local-mode (LM) and normal-mode molecules, respectively. It is demonstrated that the LM molecule prepared in a LM characteristic state is much more suitable to realize quantum computation. In addition, by introducing a section of entanglement and energy transfer, we investigate the relationship between the two quantities generally. The dynamics between entanglement and energy transfer can reveal a good synchronism under some conditions. Moreover, the intramolecular coherence properties presented by the coherence visibility are discussed in some cases. (paper)
[en] The ionization spectrum of sulfur dioxide has been successfully studied by using the symmetry-adapted-cluster configuration-interaction (SAC-CI) general-R and SD-R methods and the basis set correlation-consistent polarized valence triple-zeta (cc-pVTZ). The SAC-CI general-R method reproduces the experimental spectrum well for both the main peaks and the satellite peaks of ionization spectrum of SO2. The sequence of ionic states corresponding to main peaks of SO2 has been re-determined according to the SAC-CI conclusions and it is reordered as X-bar 2A1, Ã2B2, B-bar 2A2, C-bar 2B1, D-bar 2A1, Ē2B2 and F-bar 2A1. Besides, the equilibrium structures and adiabatic ionization potentials (AIPs) of ionic states of main peaks of SO2 are calculated by using the SAC-CI SD-R method. (atomic and molecular physics)
[en] It is known that microbes obtained in the rock having sulfur and uranium have the highly ability in extraciting uranium (21-24 %). An experiment was carried out in the leaching process using those microbes and T. ferrooxodans 402 which has the capability in extracting uranium on 28 %. Four combination treatments has been done in this research using ATCC suspension for the medium of microbes as well as the solution for the process. From the data obtained, the extracting ability of microbe for uranium shows no statistical significant difference between treatments. Generally, the combination treatment tends to decrease the capability of uranium extraction which being possessed by the microbe. The highly yield uranium extraction was found on the combination treatment used TP-4/1 with CB-17/3, T.ferrooxidans 10435, or with T. ferrooxidans 402, while other treatment only gave yield around 6 to 10 % uranium. (authors). 11 refs, 2 figs, 4 tabs