摘要:
A method is provided for making shaped self-supporting carbon-fiber structure by initially forming a fluid mixture of curable binder and carbon-fiber. The mixture is poured into a mold, and a vacuum is applied to the mold to effect the separation of excess binder. Cure is effected of the residual binder to produce a removable self-supporting shaped carbon-fiber structure.
摘要:
Boron nitride is coated on filaments of elemental carbon and/or silicon carbide, the coated filaments are contacted with an infiltration-promoting material containing elemental carbon to produce a preform wherein the filaments are substantially parallel and each filament is enveloped with infiltration-promoting material, and the preform is infiltrated with a molten solution of boron and silicon producing a composite containing boron nitride coated filaments.
摘要:
A confocal scanning system for the multispectral imaging of fluorescence from a tissue sample based on time domain mapping of spectral components of the fluorescence using coated fiber tips disposed on multimode optical fibers. A fiber grating spectrometer based on two serial arrays of coated fiber tips disposed on multi-mode fiber, and delay lines between them provide spectral slices of the florescence. The coated fiber tips are arranged such that the shortest wavelength spectral components are reflected first and the longest wavelength components last. Fiber-based delay lines delay the reflections from each successive fiber tip such that they are uniformly separated in time, and in the order of its spectral wavelength number. The spectral bins are used to colorize the images to show the presence of abnormal tissue at cellular spatial resolution. A second scan with increased laser flux can destroy the diseased tissue revealed by the first scan.
摘要:
The present invention is a confocal scanning system for the multispectral imaging of fluorescence from a tissue sample based on the mapping of the spectral components of the fluorescence into the time domain using coated fiber tips disposed on multimode optical fibers. A fiber grating spectrometer based on two serial arrays of coated fiber tips disposed on multi-mode fiber, and delay lines between them provide spectral slices of the florescence. The coated fiber tips are arranged such that the shortest wavelength spectral components are reflected first and the longest wavelength components last. Fiber-based delay lines delay the reflections from each successive fiber tip such that they are uniformly separated in time, and in the order of its spectral wavelength number. The spectral bins are used to colorize the images to show the presence of abnormal tissue at cellular spatial resolution. A second scan with increased laser flux can destroy the diseased tissue revealed by the first scan.
摘要:
Fibrous material is coated with boron nitride and a silicon-wettable material, the coated fibrous material is admixed with an infiltration-promoting material which is at least partly elemental carbon and the mixture is formed into a preform which is infiltrated with a molten solution of boron and silicon producing a composite containing boron nitride coated fibrous material.
摘要:
Fibrous material is coated with boron nitride and a silicon-wettable material, the coated fibrous material is admixed with an infiltration-promoting material which is at least partly elemental carbon and the mixture is formed into a preform which is infiltrated with molten silicon producing a composite containing boron nitride coated fibrous material.
摘要:
Fibrous material is coated with boron nitride and a silicon-wettable material, the coated fibrous material is admixed with an infiltration-promoting material which is at least partly elemental carbon and the mixture is formed into a preform which is infiltrated with a molten solution of boron and silicon producing a composite containing boron nitride coated fibrous material.
摘要:
A textile yarn ring spinning or twisting apparatus of the type comprising a spindle for carrying a yarn support tube, the spindle being rotatable about its axis to enable yarn to be wound on the tube to form a yarn package, a yarn reserve winding member around which yarn may be wound prior to the doffing of a wound package from the spindle, and a yarn severing device so positioned adjacent the axis of the spindle and between the reserve winding member and an adjacent portion of the spindle on which the end of the package is located as to engage yarn extending from the reserve winding member to the wound package on the spindle. In accordance with the invention the drive mechanism enables relative rotation between the reserve winding member and the severing device so that the length of yarn extending from the package on the spindle to the reserve winding member may be severed.
摘要:
Boron nitride is coated on filaments of elemental carbon and/or silicon carbide, the coated filaments are contacted with an infiltration-promoting material containing elemental carbon to produce a preform wherein the filaments are substantially parallel and each filament is enveloped with infiltration-promoting material, and the preform is infiltrated with molten silicon to produce a composite containing boron nitride coated filaments.
摘要:
A method of infiltration forming silicon carbide bodies having an improved surface finish comprises, infiltrating a porous carbonaceous preform with molten infiltrant to form a silicon carbide body. The body is heated in an inert atmosphere or vacuum to a temperature where the infiltrant is molten while the body is positioned in contact with an infiltrant wicking means. Preferably, the wicking means has infiltrant wicking capillaries at least as large as the infiltrant wicking capillaries in the body. Capillary force draws excess infiltrant on the surface of the body from the surface leaving the reaction formed silicon carbide body with a surface substantially free of excess infiltrant droplets.