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81.
Jennings B. Gordon Jr. 《Rocks & Minerals》2013,88(6):471-472
Dark green and brilliantly gemmy, these gahnite crystals make excellent micromount specimens. 相似文献
82.
The morphology of early-age C–S–H, often referred to as outer product or low-density C–S–H, is generally accepted to be fibrillar and forms mainly during the early stages of hydration. This paper reports the effect of drying on the microstructure in young tricalcium silicate paste, which provides insight into the mechanism that leads to the fibrillar morphology. During the first few days after C3S is mixed with water, the morphology of C–S–H is more affected by drying rate than by relative humidity. This sensitivity is most apparent at partial pressures greater than 85%. During this time, the fibrillar C–S–H product can be suppressed by drying C3S paste samples very slowly prior to imaging. This approach is interpreted as evidence that this fibrillar morphology, which naturally form over time, grow as tiny colloidal particles that rearrange during the early stages of hydration, leading to well-established larger scale morphologies. 相似文献
83.
84.
E. C. C. Vasconcellos D. A. Jennings K. M. Evenson 《Journal of Infrared, Millimeter and Terahertz Waves》1986,7(2):291-292
We measured the frequency, the relative polarization and the pump frequency offset of the single FIR laser line obtained by optically pumping ethyl alcohol C2H5OH with a cw CO2 laser. 相似文献
85.
Literature on disasters provides the focus for student-based learning exercises in civil and architectural engineering at Queen's University, Belfast, which have been ongoing since 1994. Incorporating these studies in the early part of the curriculum helps students to reorientate from their previous mainly science-based study by gaining some knowledge of the roles, responsibilities, priorities, and work practices of engineers in a way that would not be possible through lectures. In view of the influence of disasters on engineering thinking and work practice, they should have a much larger influence than they currently do on curriculum development. 相似文献
86.
To evaluate the utility of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) as a cancer therapeutic, we created leucine zipper (LZ) forms of human (hu) and murine (mu) TRAIL to promote and stabilize the formation of trimers. Both were biologically active, inducing apoptosis of both human and murine target cells in vitro with similar specific activities. In contrast to the fulminant hepatotoxicity of LZ-huCD95L in vivo, administration of either LZ-huTRAIL or LZ-muTRAIL did not seem toxic to normal tissues of mice. Finally, repeated treatments with LZ-huTRAIL actively suppressed growth of the TRAIL-sensitive human mammary adenocarcinoma cell line MDA-231 in CB.17 (SCID) mice, and histologic examination of tumors from SCID mice treated with LZ-huTRAIL demonstrated clear areas of apoptotic necrosis within 9-12 hours of injection. 相似文献
87.
88.
S. Gerard Jennings 《Aerosol science and technology》2013,47(3):348-349
Copyright 2013 American Association for Aerosol Research 相似文献
89.
Fugitive dust generated by industrial haul roads can be reduced by windbreaks placed upwind or downwind of the road. For an elementary wind profile downwind of a windbreak, the fractional efficiency has been predicted as a function of downwind distance, wind speed and windbreak height and porosity. An analytical model and computer algorithm are proposed to enable engineers to predict the fractional efficiency for any source and wind profile of their choosing. 相似文献
90.