Abstract: It is an object of the present invention to provide a light-emitting element with high light emission efficiency and with a long lifetime. A light-emitting device comprises a first electrode, a second electrode, a light-emitting layer, a first layer, and a second layer, wherein the first layer is provided between the light-emitting layer and the first electrode, the second layer is provided between the light-emitting layer and the second electrode, the first layer is a layer for controlling the hole transport, the second layer is a layer for controlling the electron transport, and light emission from the light-emitting layer is obtained when voltage is applied to the first electrode and the second electrode so that potential of the first electrode is higher than potential of the second electrode.
Type:
Grant
Filed:
February 13, 2012
Date of Patent:
August 12, 2014
Assignee:
Semiconductor Energy Laboratory Co., Ltd.
Inventors:
Satoshi Seo, Tsunenori Suzuki, Kaoru Ikeda
Abstract: According to the invention there is provided a railway sleeper having a formed inverted channel-shaped section the ends of which have their upper surfaces downwardly inclined and shaped in a corrugated fashion to add strength and rigidity to said ends.The `dished spade` end contour of the sleeper may be pressed from a standard rolled steel channel section. By virtue of the stronger ends thus produced these portions can sustain a greater load than the conventional design hitherto--this means that the length of the sleeper according to this invention may be much shorter, e.g. 20% less than the conventional design for the same load bearing capacity, representing a considerable cost savings. The shape facilitates stacking, and lateral insertion beneath the track for track maintenance and replacement etc.
Abstract: A railroad crosstie is constructed from at least two individually distinct rail support blocks interconnected by a web system which is fastened to the blocks and which comprises at least one self-supporting rigid sheet member adapted to be buried in the roadway ballast when the tie is in place. The blocks are selected to support and secure rails in conventional manner, and the interconnecting web system holds the blocks in relative position in the roadbed. The rigid sheet member adapted to be buried in the roadway ballast is advantageously disposed or provided with means such as horizontal longitudinal corrugations to interact mechanically with the particles of standard railroad ballast, whereby the tie resists being withdrawn from the roadbed.