Abstract: The photostability of organic material is enhanced by the incorporation of a plurality of particles which may for example have a diameter of 0.03 microns to 2.5 microns. The organic material may be a light absorbing material and may be photoluminescent or electroluminescent. Compositions in accordance with the invention incorporating an electroluminescent material of enhanced photostability may be used in an Organic Light Emitting Diode (OLED).

Abstract: A method and an apparatus for automatically measuring the thickness and the roughness of elongated articles, such as wooden boards. The device comprises a housing having an opening therethrough to receive at least a portion of a board to be measured. At least one contact probe is provided in the housing and is biased against at least one surface of the board to sense irregularities in the flatness of the surface along a measured length thereof. A measuring circuit is connected to the contact probe to provide a measurement signal representative of the sensed irregularities and variations in thickness. A distance measuring device is also provided in the housing to measure the distance of displacement of the board past the contact probe. An output display means indicates selected ones of the measurements obtained. A computing means accumulates measured values of the means, minimum and maximum thickness, for a group of boards and permits the extraction of such statistical information.

Abstract: The disclosure herein describes a trocar particularly intended for use in laparoscopic tubal cauterization and formed of: a puncturing sharp-pointed instrument, a cannula with a flange at one end thereof, a flexible insulating ring which is received in the flange recess bore, and a collar secured in the flange bore. The collar retains the ring in the flange while allowing it to flex as the puncturing instrument is introduced in the cannula or disassociated therefrom. The puncturing instrument, cannula and collar are made of inexpensive bio-compatible plastic materials while the ring is made of rubber; consequently, the trocar is disposable after use.

Abstract: The present invention relates to a double leaf filter head for drawing clear samples from a liquid to be analysed. The filter head is of especial use in drawing samples of phoshoric acid whose SO.sub.4 .sup.-.sup.- ion content is to be analysed by turbidimetric methods.