| Fracture Toughness of an Al-Li-Cu-In Alloy |
92 |
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| Authors:
John A. Wagner; Richard P. Gangloff; NATIONAL AERONAUTICS AND SPACE ADMINISTRATION HAMPTON VA LANGLEY RESEARCH CEN TER
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 | Al-Li-Cu alloys were studied for both fracture toughness and crack initiation and growth. Mechanical properties of aa2090-T81 and an indium enhanced aa2090-T6 were examined. The effects of indium addition were investigated. Processing was studied to eliminate variations in microstructure. Explanations for observed behavior are given. |
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| The Effect of Copper, Chromium, and Zirconium on the Microstructure and Mechanical Properties of Al-Zn-Mg-Cu Alloys |
91 |
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| Authors:
John A. Wagner; R. N. Shenoy; NATIONAL AERONAUTICS AND SPACE ADMINISTRATION HAMPTON VA LANGLEY RESEARCH CEN TER
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| The effect of systematic variation of copper, chromium, and zirconium contents on the microstructure and mechanical properties of 7000-type aluminum alloy was evaluated; ingots with 1.5, 2.0. and 2.5 wt pct copper were cast with either 0.1 pct Zr or 0.20 pct Cr; fracture toughness and tensile properties were evaluated for each alloy in both the peak aging, T8, and the overaging, T73, conditions; results showed that dimpled rupture essentially ... |
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| Retinal Derived Growth Factor: A Regulator of Neural Regeneration and Revascularization in Wound Healing |
01 DEC 89 |
8 pages |
| Authors:
John A. Wagner; DANA-FARBER CANCER INST BOSTON MA
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 | Retinal Derived Growth Factor (a heparin binding growth factor that is identical to aFGF (acidic Fibroblast Growth Factor)) stimulates neurite outgrowth in vitro. We have established a model system that will allow us to determine if a gradient of FGF can cause nerve regeneration in vivo and that this regeneration is predominantly due to increased neurite outgrowth by sensory nerves. Keywords: Acidic fibroblast growth factor; Retina derived growth factor; Nerve ... |
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| Age Hardening Characteristics and Mechanical Behavior of Al-Cu-Li-Zr-In Alloys |
89 |
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| Authors:
John A. Wagner; NATIONAL AERONAUTICS AND SPACE ADMINISTRATION HAMPTON VA LANGLEY RESEARCH CEN TER
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| An investigation was conducted to determine the age hardening response and cryogenic mechanical properties of superplastic Al-Cu-Li-Zr-In alloys; two alloys with compositions Al-2.65Cu-2.17Li-0.13Zr (baseline) and Al- 2.60Cu-2.34Li-0.16Zr-0.17In were scaled up from 30 lb. permanent mold ingots to 350 lb. DC (direct chill) ingots and thermomechanically processed to 3.2 mm thick sheet; the microstructure of material which contained the indium addition was partially recrystallized compared to baseline alloy when solution heat ... |
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| Retinal Derived Growth Factor: A Regulator of Neural Regeneration and Revascularization in Wound Healing |
22 DEC 87 |
14 pages |
| Authors:
John A. Wagner; DANA-FARBER CANCER INST BOSTON MA
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| Acidic Fibroblast Growth Factor (aFGF), which is identical to Retina Derived Growth Factor (RDGF), is a growth factor that stimulates neural differentiation and the formation of neurites. Work performed under this contract is determining if a gradient of aFGF can stimulate neurites growth in the direction of increasing aFGF concentrations. Preliminary experiments establishing conditions for a slow release of aFGF over a period of several days to create such a ... |
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| Research in Seismology: Earthquake Magnitudes. |
11 OCT 1976 |
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| Authors:
Otto W. Nuttli; So Gu Kim; Huei-Yuin Wen; John A. Wagner; SAINT LOUIS UNIV MO DEPT OF EARTH AND ATMOSPHERIC SCIENCES
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| This report presents results of a search for earthquakes in Eurasia that have anomalous ratios of body-wave magnitude to surface-wave magnitude values. Results of a study of mainshock-aftershock sequences are also provided. Earthquakes occurring along the plate margin of Eurasia were found to be non-anomalous. Anomalous earthquakes are confined to the continental interior, with about 18% of the intraplate earthquakes studied having anomalous (m sub b): (M sub S) values; ... |
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