Evaluation of Elemental and Black Carbon Measurements from the GAViM and IMPROVE Networks

The GAViM program provides fine particulate and visibility data for several remote locations in Canada. Two long-term intercomparison studies between the GAViM and a major U.S. aerosol monitoring network, IMPROVE, were used to evaluate the uncertainty in the analytical data produced by proton induced x-ray emission (PIXE), proton elastic scattering analysis (PESA), and gravimetric analysis. GAViM and IMPROVE agreed well for elements from Fe to Zn where PIXE is the most sensitive; the relative difference between the 2 networks for Fe and Zn was <2%. Some lighter elements, e.g., sodium or sulphur, revealed a difference of 10-20%. Furthermore, an empiric conversion scheme for the GAViM absorption data produced by the laser integrated plate method (LIPM) was derived from the comparison to the IMPROVE thermal/optical reflectance (TOR) data. This conversion depends on the aerosol composition and is therefore site specific. It allows estimation of the elemental carbon concentrations from the historic raw light absorption values obtained by LIPM. If the mass attenuation coefficient of the fine aerosol collected at the 2 remote GAViM sites is assumed to be equal to 10 m 2 /g, then the results imply that the light absorption coefficient measured by LIPM is generally higher than the true value by up to a factor of 1.3 or 1.8, respectively. In both cases, LIPM overestimated the black carbon content, mostly for the lightly loaded samples.     

Phase Relationships and Physical Properties of Homologous Compounds in the Zinc Oxide-Indium Oxide System

Equilibrium phase relationships in the ZnO-In₂O₃ system were determined between 1100° and 1400°C using solid-state reaction techniques and X-ray diffractometry. In addition to ZnO and In₂O₃, nine homologous compounds, Zn _k In₂O _{k +3} (where k = 3, 4, 5, 6, 7, 9, 11, 13, and 15), were observed. Electrical conductivity and diffuse reflectance of the k = 3, 4, 5, 7 and 11 members were measured before and after annealing at 400°C for 1 h under forming gas (4%₂-96% N₂). Room-temperature conductivity increased as k decreased, because of increased carrier concentration as well as increased mobility. In general, transparency in the wavelength range of 450-900 nm increased as k increased. Reduction in forming gas resulted in increased conductivity and reduced transparency for all compounds measured. The highest room-temperature conductivity measured, 270 S/cm, was that of reduced Zn₃In₂O₆.     

Präparation von nichtmetallischen Werkstoffen für die lichtmikroskopische Untersuchung

Preparation of Non-Metallic Materials for Examination under an Optical Microscope Tests carried out show that the comparatively elaborate procedures necessary to produce thin polished sections can in many cases be satisfactorily replaced by more economical machining techniques. Considerable time and cost savings have been made possible by preparing monolithic specimens using a high-speed milling machine and microsections using a low-speed saw. This applies particularly to the use of the low-speed saw in quality control for components made of glass fibre reinforced polyesters. Another important application is the preparation of specimens of synthetic resin-impregnated graphite for corrosion resistance tests using a high-speed milling machine.     

Quantitative determination of vitamin A in liver and liverwurst using high pressure liquid chromatography (HPLC)

Samples of liver sausage and liver tissue from slaughtered animals were analysed for pre-formed vitamin A. A sensitive reversed phase HPLC method with fluorescence detection was used to determine the amount of free and esterified retinol in extracts of these samples. Under our chromatographic conditions retinyl myristate and linoleate run together as do retinyl palmitate and oleate. The contents of all forms of vitamin A were expressed in milligrams of all-trans retinol per 100 g wet weight. The average concentrations of total vitamin A for turkey, pig, calf, beef, and chicken liver were 42.31, 38.15, 22.74, 14.98, and 13.22, respectively. In addition to these differences, the fatty acid composition of liver retinyl esters, as well as the amount of retinol, also varied considerably among species. Approximately 95% of the hepatic vitamin A was present as retinyl ester with retinyl palmitate/oleate as the main ester fraction. The second most abundant fatty acid in the retinyl ester fraction of calf, beef, and chicken liver was stearic acid followed by myristic/linoleic acid. An increment of retinol, however, was also found in these tissue samples. By contrast, in turkey liver the retinol fraction was increased and therefore both retinyl stearate and retinol were present in nearly equal amounts, whereas the retinyl ester fatty acids from pig liver contained relatively more myristate/linoleate and less stearate than those from liver of the other domestic animals (apparently a hallmark of pig liver). The retinol and retinyl ester pattern present in liver sausage was similar to, but not identical with, that of pig liver.(ABSTRACT TRUNCATED AT 250 WORDS)     

Die löslichkeitskonstanten der zinkhydroxidchloride-einbeitrag zur kenntnis der korrosionsprodukte des zinks

The solubilities of zinc hydroxychloride II and III have been studied at 25°C in solutionsof the constant ionic strength I = 0·2M. From experimental data the following values for equilibrium0842 constants are deduced: II:Zn(OH)_1,6 Cl_0,4: log[Zn²⁺] [Cl⁻]^10,4 [H⁺]^−1,6 = 8·22 ± 0,1 III: Zn(OH)_1,794 Cl_0,206: log[Zn²⁺] [Cl⁻]^0,206 [H⁺]^−1.794 = 9·84 ± 0,05. A value of K₁ = 6 ± 2 has been estimated for the equilibrium Zn²⁺ + Cl⁻ZnCl⁺. The relative stabilities of zinc hydroxychlorides and zinc hydroxides are represented with the aid of a predominance area diagram. Comparing recent data on the solubility of hydrozincite it is seen that zinc hydroxychlorides are not stable in natural waters.     

Vergleichende Glycerinbestimmungen im Wein nach der Jodid- und Kalkmethode

Ohne ZusammenfassungMitteilung aus den Laboratorien der Landes-Versuchsstation St. Michele a. E. und der Landes-Versuchsstation des Herzogtums Kärnten zu Klagenfurt.     

Mineralogy of air-pollution-control residues from a secondary lead smelter: environmental implications

The mineralogy and solubility of air-pollution-control (APC) residues from a secondary lead (Pb) smelter have been studied on samples from the Príbram smelter, Czech Republic, recycling car batteries, with the emphasis on their potential environmental effect. The presence of dominant anglesite (PbSO4) and laurionite (Pb(OH)Cl) was observed in a sintered residue from after-burning chambers (800-1000 degrees C). In contrast, low-temperature Pb-bearing phases, such as KCl x 2PbCl2 and caracolite (Na3Pb2(SO4)3Cl), were detected in the major APC residue from bag-type fabric filters. Metallic elements, zinc (Zn), cadmium (Cd), and tin (Sn) were found homogeneously distributed within this residue. The formation of anglesite, cotunnite (PbCl2), (Zn,Cd)2SnO4, and (Sb,As)2O3 was observed during the sintering of this APC residue at 500 degrees C in a rotary furnace. The 168 h leaching test on filter residue, representing the fraction that may escape the flue gas treatment system, indicated rapid release of Pb and other contaminants. Caracolite and KCl x 2PbCl2 are significantly dissolved, and anglesite and cotunnite form the alteration products, as was confirmed by mineralogical analysis and PHREEQC-2 modeling. The observed Pb-bearing chlorides have significantly higher solubility than anglesite and, following emission from the smelter stack, can readily dissolve, transferring Pb into the environmental milieu (soils, water, inhabited areas).