Home About us Contact
|
Home About us Contact | ||
|
|
||
Situ Process (situ + process)
Selected AbstractsComposite Zirconium Silicides Through an In Situ ProcessINTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 1 2006Jérôme Canel Zirconium silicides are being investigated for use as neutron reflector materials for the next generation of nuclear power devices. Hot isostatically pressed monolithic Zr3Si2 and reactive sintered ZrXSiY composite are currently under development. The composite is obtained in situ and contains a ZrSi matrix embedding shell-like Zr, Zr2Si, and ZrSi2 domains with volume ratios depending on the initial Zr/Si ratio. Despite the lack of information on the mechanical properties of zirconium silicides, the composite structure is assumed to have enhanced fracture toughness; conditions to improve it further are discussed on the basis of microstructural observations of crack deflection. [source] Growing SiC Nanowires on Tyranno-SA SiC FibersJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 4 2004Wen Yang A new in situ process for growing SiC nanowires on Tyranno-SA SiC fibers (2-D, plain-woven) was developed using the thermal decomposition of methyltrichlorosilane in hydrogen. The process was performed using a chemical vapor infiltration system. ,-SiC nanowires ,100-nm thick and several tens of micrometers long were successfully synthesized on the fibers. The growing of the SiC nanowires suggests a conditions-dependent process. [source] In Situ Polymerisation of Polyamide-6 Nanocompounds from Caprolactam and Layered SilicatesMACROMOLECULAR MATERIALS & ENGINEERING, Issue 1 2009Bernd Rothe Abstract An in situ process for the production of polyamide-6 nanocompounds is investigated as an alternative to melt compounding. During the in situ production, the layered silicates are dispersed in the monomer caprolactam before the polymerisation in a twin screw extruder, leading to an intercalation of the silicates. The production of a polyamide compound containing 0, 2 and 4 wt.-% nanoscale silicates was successful. An improvement of the elastic modulus of approximately 30,60% was reached. The figure shows the TEM micrograph of a nanocompound containing 2 wt.-% nanoclay at a magnification of 30,000×. [source] Further analysis of the population history of ancient EgyptiansAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2009Michael A. Schillaci Abstract The origins of state formation in ancient Egypt have been the focus of recent research utilizing biological data to test hypotheses regarding in situ development of local groups, or large-scale in-migration, possibly by an invading army. The primary goal of the present research is to further test these hypotheses. Our secondary goal is to compare different distance measures and assess how they might affect interpretation of population history. We analyze craniodental nonmetric data using several different measures of biological distance, as well as a method for estimating group diversity using multidimensional scaling of distance estimates. Patterns of biological variation and population relationships were interpreted in temporal and geographic contexts. The results of our analyses suggest that the formation of the ancient Egyptian state likely included a substantial in situ process, with some level of contribution by outside migrants probable. The higher level of population structure in Lower Egypt, relative to Upper Egypt, suggests that such influence and migration by outsiders may not have been widespread geographically. These findings support, but serve to refine further those obtained by the second author in a previous study. Moreover, our comparison of distance measures indicates that the choice of measure can influence identification and interpretation of the microevolutionary processes shaping population history, despite being strongly correlated with one another. Am J Phys Anthropol 2009. © 2009 Wiley-Liss, Inc. [source] | ||||||||||