The thermal power of aluminum nitride at temperatures between 1350 and 1650 deg C in argon and nitrogen atmospheres

The test apparatus for measuring the thermal voltage of aluminum nitride for temperature differences of up to + or - 60 C between 1350 and 1650 C is described. The thermal power and its homogeneous proportion are determined and the heat transfer of the migration ions resulting from the homogeneous thermal power is calculated. The conduction mechanism in aluminum nitride is discussed

The Hydraenidae (Insecta: Coleoptera) of the Maltese Archipelago (Central Mediterranean)

The Hydraenidae of the Maltese Archipelago are reviewed, based on literature records and examination of historical and recently collected specimens. A total of eleven species is included of which Hydraena (s.str.) sub impressa REY, Ochthebius (s.str.) fossulatus MULSANT, O. (s.str.) punctatus STEPHENS, and O. (s.str.) viridis PEYRON (species complex) are recorded from the Maltese Islands for the first time. The records of the following four species by CAMERON & CARUANA GATTO (1907) are based on misidentifications: Hydraena (s.str.) nigrita GERMAR (= H. (s.str.) subimpressa REY), Ochthebius (s.str.) foveolatus GERMAR (= O. (s.str.) eyrei JACH, and O. (s.str.) fossulatus MULSANT), O. (s.str.) lanuginosus REICHE & SAULCY (= O. (s.str.) punctatus STEPHENS), and O. (s.str.) sub integer MULSANT & REy (= O. (s.str.) celatus JACHpeer-reviewe

Observations of the Biology of \u3ci\u3ePhasgonophora Sulcata\u3c/i\u3e (Hymenoptera: Chalcididae), a Larval Parasitoid of the Twolined Chestnut Borer, \u3ci\u3eAgrilus Bilineatus\u3c/i\u3e (Coleoptera: Buprestidae), in Wisconsin

Phasgorzophora sulcata Westwood was the principal larval parasitoid of Agrilus bilineatus (Weber) during a study conducted in a natural oak-hardwood forest in the Kettle Moraine State Forest, Jefferson County, Wisconsin. Mean percent larval parasitism was 10.5%. Mean A. bilineatus and P. sulcata densities were, respectively, 53.0 and 6.1 adults per square meter of bark. The theoretical developmental threshold temperatures for over- wintering A. bilineatus and P. sulcata larvae were 17.8 and 19.l0C, respectively. The peak flight period of P. sulcata (9 July 1980) occurred ca. 3 weeks after the A. bilineatus peak flight (18 June 1980) at about the time of peak A. bilineatus egg eclosion. The P. sulcata sex ratios (malexfemales) for laboratory-reared and field-captured adults were 1:1.35 and 1:3.22, respectively

Global Mapping Function (GMF): A new empirical mapping function based on numerical weather model data

Troposphere mapping functions are used in the analyses of Global Positioning System and Very Long Baseline Interferometry observations to map a priori zenith hydrostatic and wet delays to any elevation angle. Most analysts use the Niell Mapping Function (NMF) whose coefficients are determined from site coordinates and the day of year. Here we present the Global Mapping Function (GMF), based on data from the global ECMWF numerical weather model. The coefficients of the GMF were obtained from an expansion of the Vienna Mapping Function (VMF1) parameters into spherical harmonics on a global grid. Similar to NMF, the values of the coefficients require only the station coordinates and the day of year as input parameters. Compared to the 6-hourly values of the VMF1 a slight degradation in short-term precision occurs using the empirical GMF. However, the regional height biases and annual errors of NMF are significantly reduced with GMF