Abstract:
A power meter for measuring radiation is disclosed, which includes: a partially transmitting body able to absorb some fraction of radiation incident on the body and to re-emit absorbed energy; and, pyrometric means lying outside the path of incident radiation, for measuring radiation emitted by the body. The amount of emitted radiation is proportional to the intensity of incident radiation. The characteristics of a beam of ultraviolet, visible or infrared radiation are substantially unaffected by transmission through the body, thus permitting use of the beam while it is either continuously or discontinuously monitored.
Abstract:
A PROCESS FOR THE CONTROL OF DUST GENERATED BY NORMALLY DUSTY SOLID PARTICULATE MATERIAL SMALLER THAN 10 MESH IN SIZE, COMPRISING MIXING FROM ABOUT 0.02 TO LESS THAN 1.0 PERCENT, AND PREFERABLY FROM ABOUT 0.02 TO ABOUT 0.75 PERCENT, BY EIGHT, FIBRILLATABLE POLYTETRAFLUOROETHYLENE (HEREINAFTER REFERRED TO AS PTFE) WITH SAID MATERIAL TO FORM AN INTIMATE MIXTURE AND THEN WORKING THE MIXTURE SUFFICIENTLY AT A TEMPERATURE ABOVE 20*C BUT BELOW THE TRANSITION POINT OF SAID PTFE TO FORM ENOUGH PTFE FIBERS TO PRODUCE A WEAK, ESSENTIALLY DUSTLESS AGGLOMERATE FROM SAID DUSTY MATERIAL. A COHERENT, WEAK AGGLOMERATED DUSTLESS SOLID PARTICULATE MASS LACKING RESISTANCE TO PRESSURE OF MECHANICAL SHOCK AND SIMULTANEOUSLU PLIABLE AND FRIABLE AT AMBIENT TEMPERATURES, YET VISUALLY DISTINGUISNABLE FROM THE NORMALLY DUSTY MATERIAL FROM A MIXTURE OF DUSTY DISCRETE AGGLOMERATE IS FORMED FROM A MIXTURE OF DUSTY DISCRETE PARTICLES IN THE SIZE RANGE FROM LESS THAN ABOUT 1 INCH TO ABOUT 2000 MICRONS, AND FIBRILLATABLE PTFE IN AN AMOUNT FROM ABOUT 0.02 BUT LESS THAN 1 PEERCENT BY WEIGHT, BASED ON TOTAL SOLIDS, BY WORKING THE MIXTURE IN A DRY OR RELATIVELY DRY STATE WITH A WORKING ACTION IN AN UNCONFINED ZONE AT A TEMPERATURE INE XCESS OF 20*C., BUT BELOW THE SINTERING TEMPERATURE OF PTFE, WITHOUT CHANGING THE PRIMARY PARTICLES SIZE RANGE OF THE MATERIAL.
Abstract:
This is a process for growing non-epitaxially a different crystal upon a base crystal surface and thereafter destroying said different crystal, thereby generating a uniformly random arrangement of surface irregularities which are independent of lattice orientation in the base crystal. The texture of the treated surface is unlike prior art surfaces, whether produced chemically or mechanically, and specular reflections are essentially eliminated.
Abstract:
A perforated printed circuit board is plated with a smooth and ductile deposit of copper from a high acid-low copper sulfate bath under conditions that give a copper deposit having a surface to hole thickness ratio of less than unity. Plating is carried out at a current density of between 15 and 60 asf using a bath maintained at a temperature of between 20* and 30*C., said bath containing 70-150 g/l of CuSO4.5H2O and 175-300 g/l of H2SO4 and preferably including 1 or more grain refining agents. The process is applicible to boards up to 1/8 inch thick and wherein the ratio of board thickness to hole diameter is between about 1/1 and 4/1.
Abstract:
The process and the improved black chromium plating produced thereby comprising electroplating chromium from an aqueous bath containing hexavalent chromium, trivalent chromium and a lower aliphatic carboxylic acid such as acetic acid. The hexavalent chromium compound is present in a range equivalent to 150-425 grams per liter of chromic acid anhydride; the trivalent chromium is present in an amount 8-30 grams per liter; and the total carboxylic acid, in both acid and carboxylate form, is in the range of 170-350 grams per liter of acid. The electroplating is conducted at 60-85* F. and with a cathode current density of 751000 amperes per sq. ft. The trivalent chromium concentration given above not only permits reproducable lustrous black chromium plating but also greatly decreases the break-in period for the bath. A further addition of ferric ions of up to 25 grams per liter further decreases or completely eliminates the break-in period and also increases the maximum operating temperature of the plating bath to 105* F. When iron is utilized, the combined concentration of trivalent chromium and iron should not exceed 35 grams per liter.
Abstract:
THIS INVENTION COMPRISES A COMPOSITE OR LAMINATED METALLIC COATING, AND A PROCESS FOR MAKING SUCH COATING, COMPRISING A FIRST LAYER OF NICKEL AND AN OVERLYING LAYER OF CHROMIUM, THE LAMINATE BEING CRACKED IN A CRAZE PATTERN IN THE RANGE OF 300 TO 3000 CRACKS PER LINEAL INCH PREPARED BY ELECTRODEPOSITING ON A METAL SUBSTRATE A STRESSED LAYER OF NICKEL AND THEREAFTER ELECTRODEPOSITING ON THIS STRESSED LAYER OF NICKEL A STRESSED LAYER OF CHROMIUM ADHERENT TO THE STRESSED LAYER OF NICKEL AND HEATING THE RESULTANT LAMINATE. THE STRESSING IN THE RESPECTIVE LAYERS MAY BE EFFECTED BY MEANS OF AN ADDICTIVE IN THE ELECTROPLATING SOLUTION FROM WHICH IT IS PRODUCED. THE RESULTANT CRAZING GIVES AN IMPROVED PROTECTION AGAINST CORROSION.
Abstract:
A process is disclosed for converting basic magnesium carbonate into pure hot-pressable magnesium fluoride such as is used for the hot-pressing of infra-red radiation transmitting optical bodies. The process includes contacting a slurry of basic magnesium carbonate with carbon dioxide to form enough magnesium bicarbonate or hydrates of magnesium carbonate, in situ, to alter the particles in the slurry. Carbonation of the slurry increases solubility of the solids by establishing an equilibrium relationship in solution between the unstable magnesium bicarbonate and hydrates of magnesium carbonate particles. When the carbonated slurry is contacted with a slight excess of hydrofluoric acid it precipitates solid particles of fine hydrous magnesium fluoride. Neutralization of excess hydrofluoric acid is effected with ammonium hydroxide. The solid particulate precipitate is dried and calcined to yield hot-pressable magnesium fluoride powder of exceptional purity and consistent quality. A hot-pressable magnesium fluoride powder has been prepared which has a specific and uniform refractive index, nD 1.3850 at 20* C; the powder is made up of primary particles the majority of which have an average particle diameter of greater than 5 Mu (microns), permitting the hot-pressing of the powder without grinding it.
Abstract:
A laminated card with one or more apertures, each adapted to peripherally seal an encapsulated dosimeter, is formed by bonding a foraminous, code-adaptable, rigid sheet of low-Z material with a codedly transparent sheet of low-Z material in lighttransmitting registry with particular code-holes of the rigid sheet. The laminated card may be coded to identify the person carrying it, and/or the location or circumstances related to its exposure to radiation. This card is particularly adapted for use in an instrument capable of evaluating a multiplicity of cards, substantially continuously. The coded identification from the card may be displayed by an appropriate machine, and if desired an evaluation may be recorded because of a ''''parity checking'''' system incorporated in each card, which permits ''''autocorrection.'''' Alternatively, where means for effecting the correction automatically are available, the operation of the machine may be interrupted to permit visual examination of a rejected card. The card of this invention is also coded for identifying the type of card with respect to its specific function, and whether or not a card is correctly positioned at any predetermined location during its sequential progress through the instrument in which it is evaluated. Dosimeters are evaluated and the card identified in one pass through the instrument.