CLASS: A Comprehensive Satellite Link Simulation Package

CLASS (communication link analysis and simulation system) is a software package developed for NASA to predict the communication and tracking performance of the tracking and data relay satellite system (TDRSS) services. This paper describes the capabilities of CLASS and the communication link model used, and discusses typical applications for CLASS.     

Doxazosin in the treatment of benign prostatic hyperplasia in normotensive patients: a multicenter study

A 16-week, double-blind, placebo controlled, dose titration study was done on 100 normotensive patients age 45 years or older to determine the efficacy and safety of doxazosin, a selective alpha 1-adrenoceptor antagonist, in the treatment of benign prostatic hyperplasia (BPH). Of the 41 efficacy evaluable patients 88% underwent dose titration to a maximum of 8 mg. doxazosin once daily. Maximum and average urinary flow rates increased significantly above baseline with doxazosin (2.9 ml. per second and 1.4 ml. per second, respectively) compared with placebo (0.7 ml. per second and 0.3 ml. per second, respectively). A significant effect on maximum flow rate was noted as early as week 2 of double-blind treatment at the initial efficacy evaluation. Doxazosin was superior to placebo in patient and investigator assessments of total, obstructive and irritative BPH symptoms. The onset of efficacy for total patient-assessed symptoms was significant for doxazosin compared to placebo 4 weeks after the start of the treatment regimen. Statistically significant decreases in mean blood pressure of 4 to 6 mm. Hg were noted with doxazosin compared with placebo. Adverse events, primarily mild to moderate in severity, were reported in 44% of patients given doxazosin and 30% of those given placebo. Our results strongly demonstrate that doxazosin is significantly superior to placebo in the treatment of BPH in normotensive patients, with the patient experiencing significant relief early after initiation of therapy.     

Über die Anwendung von Zirkonium im chemischen Apparatebau

Application of zirconium in chemical plant construction It ist in this decade only, that zirconium has become an established special material in chemical plant construction. Zirconium is used in particular where high corrosion resistance is required, e.g. with processes involving sulfuric, hydrochloric, nitric and phosphoric acids, chlorides (except ferric and cupric chlorides), alkalies, urea, hydrogen peroxide and lactic acid. Preferred types of equipment are reaction columns, pump casing, heat exchangers and tubing, e.g. in connection with the production of dyes, pigments (erosion resistance), foods, hydrogen peroxide and urea. The price of zirconium, though still high if compared with that of nickel-base alloys or high-alloy stainless steels is soon amortized as a consequence of the low maintenance requirement.     

Organochlorine Residues in Suspended Solids Collected from the Mouths of Canadian Streams Flowing into the Great Lakes 1974–1977

Suspended solids were collected from 105 streams on the Canadian side of the Great Lakes during snow melt and spring flow between 1974 and 1977. Analyses were performed for organochlorine and organophosphorus insecticides and three industrial chemicals. All streams sampled contained suspended solids that were contaminated with DDT, its metabolites, and polychlorinated biphenyl (PCB). The highest mean concentrations of ΣDDT (356 μg/kg) occurred in 1974 from streams draining the Niagara Peninsula and entering Lake Ontario; these were correlated to areas of high use on fruit in the past. The highest loadings by lake section, however, were along the north shore of Lake Erie involving a very much larger delivery of suspended solids. The highest concentrations of PCB were on suspended solids entering Lake Ontario in 1974 along the northern (191 μg/kg) and southwestern (172 μg/kg) shore and were associated with the high urban-industrial activity in the megalopolis of Hamilton-Burlington-Oakville-Mississauga-Toronto. However, the highest loadings occurred along Lake St. Clair where two large rivers, the Thames and Sydenham, discharge a much larger volume of suspended solids. The highest individual concentrations of HEOD (dieldrin) were found on suspended solids in two streams entering along the southwestern shoreline of Lake Ontario. However, the highest mean residues on solids for all streams was in waters entering Lake Erie (3 μg/kg) and the highest loadings were into Lake St. Clair. Endosulfan, chlordane, and heptachlor epoxide were detected in some streams entering all five lakes. No aldrin, endrin, mirex, heptachlor, or organophosphorus insecticides were detected.     

Digitalrechenprogramm zur Bestimmung von Temperaturen in Rollen und Walzen

Beschreibung instationärer, mehrdimensionaler Wärmetransportvorgänge. Das Digitalrechenprogramm “WINST” zur Berechnung der Temperaturbewegungen in Rollen und Walzen, die mit Stahlsträngen oder Walzgut in Berührung stehen. Bestimmung der Unterschiede zwischen der gröβten und kleinsten Temperatur von Punkten der Oberfläche sowie solchen innerhalb einer Rolle oder Walze während einzelner Umdrehungen. Ermittlung der gröβten, während der Abläufe der Gieβ- oder Walzvorgänge erreichten Oberflächentemperaturen. Vergleich der Rechenergebnisse mit Meβwerten.     

Reaction diffusion and associated nonequilibrium effects in the Au-Co system

Inerdiffusion in two-phase Au-Co couples was investigated using metallographic and elec-tron microprobe analyses. Deviations from local equilibrium at the moving α-@#@ α interface were observed. These deviations were significant for short (1 to 2 h duration) anneals and, as the annealing time increased, the interface compositions approached the equilibrium val-ues. The interdiffusion coefficients (~D) and intrinsic diffusivities (D_Au and D_Co) in the α-Au terminal solid solution at 950° and 900°C were determined.