Development of hydrogen resistant alloys

The most hostile operating environments in the O2/H2 Space Shuttle Main Engine are gaseous hydrogen and hydrogen/water vapor. After years of evaluating commercially available alloys, only a few high strength alloys have been found that perform satisfactorily in these environments. This paper describes the evaluation of various compositions of the Fe-Ni-Co system with elemental additions of Cr, Cb, Ti and Al. After processing, notched tensile specimens were tested in 5000 psi hydrogen at room temperature as the prime screening test. The H2/air ratio was used as the selection/rejection criteria

Seasonal Flight Patterns of Hemiptera in a North Carolina Black Walnut Plantation. 6. Tingidae and Aradidae

The seasonal flight patterns of II species of Tingidae and six species of Aradidae collected in window traps in a North Carolina black walnut plantation are described. Flying height distributions and seasonal flight activities of Corythucha ciliata (Say) and Gargaphia solani Heidemann are considered in detail

Seasonal Flight Patterns of Hemiptera (Excluding Miridae) in a Southern Illinois Black Walnut Plantation

The seasonal flight patterns of 99 species and subspecies of Hemiptera collected in window traps in a southern Illinois black walnut plantation are compared with similar data from a North Carolina black walnut plantation. Flying height distributions and seasonal flight activities of Corythucha juglandis, Orius insidiosus, Piesma cinerea, Acanthocephala terminalis, Alydus eurinus, Sehirus cinctus cinctus, Acrosternum hilare, Brochymena quadripustutata, Euschistus servus, and Euschistus variolarius are considered in detail

Annotated Bibliography of the Ambrosia Beetle \u3ci\u3eXylosandrus Germanus\u3c/i\u3e (Coleoptera: Scolytidae)

(excerpt) Xylosandrus germanus (Blandford) (= Xyleborus germanus) is an ambrosia beetle that is found in Japan, Korea, the KurU Islands, Vietnam, China, Taiwan, central Europe, and the Cnited States (Nobuchi 1981). It attacks apparently healthy plants and those that are dying or recently dead (Weber 1982). Kaneko (1967) reported X. germanus to be a serious pest on tea (Thea sp.) plants in Japan, and Heidenreich (1%0) reported it on oak (Quercus sp.) trees in Gennany. This beetle seems to be increasing in economic importance on black walnut (Juglans nigra L.) and other hardwood species in the U.S. (Weber 1982)

The Distribution of \u3ci\u3eXylosandrus Germanus\u3c/i\u3e in America North of Mexico (Coleoptera: Scolytidae)

Xylosandrus gemzanus (Blandford) (= Xyleborlus germanus), a sexually dimorphic beetle. was first described in 1894 from specimens collected in Japan; it is now also known from Korea. the Kuril Islands, Vietnam, China, Taiwan, central Europe, and the U.S. ( Sobuchi 1981)

Material technology

Advanced high pressure O2/H2 propulsion systems as exemplified by the Space Shuttle Main Engine (SSME) create challenging operating environments for materials. Many components operate in either hydrogen or hydrogen-steam environments which may significantly degrade the performance of common alloys. The objective of the materials technology projects is to develop and evaluate candidate materials for application in advanced high pressure O2/H2 propulsion systems. These new and improved materials are to improve the durability or performance of the SSME or derivative engine. The program includes projects on the following topics: (1) Hydrogen Resistant Alloys; (2) High Pressure O2 Ignition and Burning; (3) Improved Turbine Blades; (4) Improved Turbine Disk Material; (5) Impact Reactivity in High Pressure O2; and Fiber Reinforced Superalloys

Seasonal Flight Patterns of Miridae (Hemiptera) in a Southern Illinois Black Walnut Plantation

The seasonal flight patterns of 92 species of Miridae collected in window traps in a southern Illinois black walnut plantation are compared with similar data from a North Carolina black walnut plantation. Flying height distributions and seasonal flight activities of Amblytylus nasutus, Deraeocoris nebulosus, Leptopterna dolabrata, Lopidea heidemanni, Lygus lineolaris, and Plagiognathus politus are considered in detail. Six species are newly recorded for Illinois

Electrophysiologic assessment of (central) auditory processing disorder in children with non-syndromic cleft lip and/or palate

Session 5aPP - Psychological and Physiological Acoustics: Auditory Function, Mechanisms, and Models (Poster Session)Cleft of the lip and/or palate is a common congenital craniofacial malformation worldwide, particularly non-syndromic cleft lip and/or palate (NSCL/P). Though middle ear deficits in this population have been universally noted in numerous studies, other auditory problems including inner ear deficits or cortical dysfunction are rarely reported. A higher prevalence of educational problems has been noted in children with NSCL/P compared to craniofacially normal children. These high level cognitive difficulties cannot be entirely attributed to peripheral hearing loss. Recently it has been suggested that children with NSCLP may be more prone to abnormalities in the auditory cortex. The aim of the present study was to investigate whether school age children with (NSCL/P) have a higher prevalence of indications of (central) auditory processing disorder [(C)APD] compared to normal age matched controls when assessed using auditory event-related potential (ERP) techniques. School children (6 to 15 years) with NSCL/P and normal controls with matched age and gender were recruited. Auditory ERP recordings included auditory brainstem response and late event-related potentials, including the P1-N1-P2 complex and P300 waveforms. Initial findings from the present study are presented and their implications for further research in this area —and clinical intervention—are outlined. © 2012 Acoustical Society of Americapublished_or_final_versio