Commercial Aerospace Industry from the U.S. Monopoly to Duopoly

This program has been organized by the EMSA to commensurate the 50th anniversary of the experimental verification of the wave nature of the electron. Davisson and Germer in the U.S. and Thomson and Reid in Britian accomplished this at about the same time. Their findings were published in Nature in 1927 by mutual agreement since their independent efforts had led to the same conclusion at about the same time. In 1937 Davisson and Thomson shared the Nobel Prize in physics for demonstrating the wave nature of the electron deduced in 1924 by Louis de Broglie.The Davisson experiments (1921-1927) were concerned with the angular distribution of secondary electron emission from nickel surfaces produced by 150 volt primary electrons. The motivation was the effect of secondary emission on the characteristics of vacuum tubes but significant deviations from the results expected for a corpuscular electron led to a diffraction interpretation suggested by Elasser in 1925.

Download Full-text

Variations in Surface Textures of Quartz Sand using Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069466 ◽

1970 ◽

Vol 28 ◽

pp. 494-495

Author(s):

Eugene J. Amaral

Keyword(s):

Electron Microscopy ◽

Glass Industry ◽

Glass Slide ◽

Distilled Water ◽

Early Paleozoic ◽

Secondary Effects ◽

Surface Textures ◽

High Silica ◽

Sand Deposit ◽

The U.S

Examination of sand grain surfaces from early Paleozoic sandstones by electron microscopy reveals a variety of secondary effects caused by rock-forming processes after final deposition of the sand. Detailed studies were conducted on both coarse (≥0.71mm) and fine (=0.25mm) fractions of St. Peter Sandstone, a widespread sand deposit underlying much of the U.S. Central Interior and used in the glass industry because of its remarkably high silica purity.The very friable sandstone was disaggregated and sieved to obtain the two size fractions, and then cleaned by boiling in HCl to remove any iron impurities and rinsed in distilled water. The sand grains were then partially embedded by sprinkling them onto a glass slide coated with a thin tacky layer of latex. Direct platinum shadowed carbon replicas were made of the exposed sand grain surfaces, and were separated by dissolution of the silica in HF acid.

Download Full-text

The Effects of Estradiol on Chronically Damaged Human Fallopian Tubes: A SEM Study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100119934 ◽

1985 ◽

Vol 43 ◽

pp. 648-649

Author(s):

A. Toledo ◽

G. Stoelk ◽

M. Yussman ◽

R.P. Apkarian

Keyword(s):

Menstrual Cycle ◽

Epithelial Cell ◽

Secretory Cell ◽

Estrogen Therapy ◽

Fallopian Tubes ◽

Cell Surfaces ◽

Proliferative Phase ◽

Cyclic Patterns ◽

Sem Study ◽

The U.S

Today it is estimated that one of every three women in the U.S. will have problems achieving pregnancy. 20-30% of these women will have some form of oviductal problems as the etiology of their infertility. Chronically damaged oviducts present problems with loss of both ciliary and microvillar epithelial cell surfaces. Estradiol is known to influence cyclic patterns in secretory cell microvilli and tubal ciliogenesis, The purpose of this study was to assess whether estrogen therapy could stimulate ciliogenesis in chronically damaged human fallopian tubes.Tissues from large hydrosalpinges were obtained from six women undergoing tuboplastic repair while in the early proliferative phase of fheir menstrual cycle. In each case the damaged tissue was rinsed in heparinized Ringers-lactate and quartered.

Download Full-text