Abstract: A tamper-resistant package containing in an anerobic environment a leuco dye free of reducing agent which dye becomes colored upon reaction with oxygen.

Abstract: The content of oxygen, if any, that is present in a body of essentially monocrystalline semiconductor material is determined by converting by heating all of the oxygen in the body to interstitial form. The oxygen content is measured by infrared beam evaluation of the absorption band to identify the interstitial oxygen present in the material.

Abstract: This invention relates to a method and to apparatus for chemical and biochemical analyses which employ an energy-transmissive core and may employ one or more sheaths which selectively absorb, react with, and/or filter an analyte or a product of an analyte. The core is transmissive to a chosen energy carrier and it has an inlet end and an outlet end. Between these ends it has an extended length. The passage of energy through the core is modified by reason of events which occur in one or more of the sheaths or in the case where no sheath is employed, by reason of events which occur in an ambient fluid. The resulting modification of the transmitted energy is a measure of such events which in turn are a measure of the analyte. The energy may be any of several types of energy which can be transmitted through the core from end to end and which is susceptible to modification by reactions in the sheath or sheaths or ambient fluid. The energy may be electromagnetic, electrical or sonic.