摘要:
A new class of substituted 2,3-naphthalenedicarboxaldehydes (NDA) is disclosed. Such compounds are of the formula: ##STR1## wherein one or more of R.sub.1 -R.sub.8 are various substituting groups. The above compounds react, in the presence of cyanide ion, with compounds containing primary amino groups to form adducts which exhibit a high fluorescent yield and thus are readily detected and measured by fluorometric assaying techniques.
摘要:
A chemiluminescence method for assaying compounds containing primary amino groups using 1-cyano-2-substituted benz(f)- or naphth(f)-isoindole fluorescers is disclosed. The 1-cyano-2-substituted benz(f)- or naphth(f)-isoindole (CBI or CNI) is formed by reacting a compound containing a primary amino group with naphthalene-2-3-dicarboxaldehyde or anthracene-2,3-dicarboxaldehyde in the presence of cyanide ion. The reaction product of hydrogen peroxide with an oxalate ester is then combined with the CBI or CNI to form an analyte which exhibits chemiluminescence. A detector is used to measure the chemiluminescence emission from the chemiluminescence derivatized analytes. Compounds containing primary amino groups which may be assayed according to the present invention include primary amines, amino acids, peptides and catecholamines. The method can also be adapted to the analysis of trace amounts of cyanide ion and hydrogen peroxide.
摘要:
A blade fabricated of a plurality of bonded filament laminates, at least one of the laminates characterized by a plurality of continuous, collimated filaments embedded in a different matrix at the blade tip than at the blade root. The matrices are characterized by different relative impact strengths.
摘要:
A composite metallic preform tape for use as laminae in the manufacture of metallic composite articles is made from a pair of metallic foils and high strength, high modulus filaments aligned between the foils. One form of the method involves first coating either the foil inner surfaces or the filament outer surfaces, or both, with a thin, non-metallic adhesive bonding material which will decompose leaving substantially no residue upon heating at a temperature below that at which the foil and filaments will melt, and preferably below that at which they will bond together. The foil and the aligned filaments are themselves aligned and, in a continuous form of the method, are moved at substantially the same rate and in the same direction so that the coated surface is between the foil and filaments. At the same time, the foil and filaments are pressed toward one another with a force sufficient to adhesively bond together the foil and filaments and to plastically deform the foil around at least a portion of substantially each filament.In a preferred form, at least one plastically deformable, strippable outer film is applied for protection and, if desired, for a quality control record. Deformation of the foils around at least a portion of substantially each filament results in an article having a sandwich construction including centrally aligned filaments maintained in spaced apart relationship.
摘要:
A blade fabricated of a plurality of bonded filament laminates, at least one of the laminates characterized by a plurality of continuous, collimated filaments embedded in a different matrix at the blade tip than at the blade root. The matrices are characterized by different relative impact strengths.
摘要:
The composite filament laminates of a composite blade are splayed at the root thereof to receive metallic inserts therebetween. A transition material having a modulus of elasticity greater than that of the inserts and less than that of the laminates is bonded therebetween to more uniformly distribute the blade loadings into the root region.
摘要:
The top portion of a composite (boron filament/aluminum matrix) blade which is useable in a fluid flow machine is made more resistant to impact energy by forming a cavity in the boron filament layer of the tip portion of each laminate (or ply) of the blade, then filling each cavity with a resin, and then bonding together the laminates with the resin-filled cavities therein.
摘要:
A method of making a composite article having at least a minimum selected impact strength by first obtaining the impact energy absorption/shear strength relationship for the collimated filaments and matrix material comprising the article. Impact strength is improved by the selection of the relative bond strengths between constituents and the orientation of selected matrix materials relative to the impact surface of the article.
摘要:
An electronically programmable frequency correction arrangement. The frequency of a source input signal is compared to a desired frequency. Pulse stuffing techniques are utilized by which a number of pulses comprising a frequency correction signal are selectively added to the input signal so as to accurately adjust the source frequency to the desired frequency.