294 results about "Absorptance" patented technology

An excavation technique for a stratum capable of excavating a submerged stratum such as a layer containing an underground resource by using laser irradiation in liquid is provided. In this technique, a laser beam transmitted through laser transmission means 20 is irradiated in liquid 90 in form of a laser beam having a wavelength with high absorptance of the liquid 90 by laser-induced bubble generation means 35, generating a bubble flow 36, thus excavation of a submerged stratum may be carried out by using a laser-induced destruction effect. Moreover, a laser beam 41 having low absorptance of the liquid 90 is irradiated by laser irradiation means 39 and passed through the bubble flow 36, thereby applying a thermal effect to a stratum to destroy rock and excavate the stratum. The destruction effect and the thermal effect also may be cooperatively worked.

A transfer substrate includes a support base which transmits laser light with a predetermined wavelength, a photothermal conversion layer provided on the support base, and a transfer layer provided on the photothermal conversion layer, the transfer layer including at least a luminescent layer. The photothermal conversion layer is composed of a first material and a second material having different absorptances with respect to the laser light.

The present invention provides an improved solar selective multilayer coating having higher thermal stability and a process for the preparation thereof. Solar selective coatings having higher thermal stability are useful in solar steam generation, solar steam turbines to produce electricity and also on automobile engine components. In the present invention, a tandem stack of three layers of TiAlN, TiAlON and Si₃N₄ is deposited on metal and non-metal substrates at room temperature using a planar reactive direct current magnetron sputtering process. The first two layers function as the absorber and the third antireflection layer further enhances the coating's absorptance. The solar selective coatings were annealed in air and vacuum to test the thermal stability at different temperatures and durations. The coatings of the present invention deposited on copper substrates are stable in air up to a temperature of 625° C. for a duration of 2 hours and exhibit higher solar selectivity in the order of 9-10 and these coating also show no change in the absorptance and the emittance values even after vacuum annealing at 600° C. for 3 hours. Coatings deposited on copper substrates showed no significant degradation in the optical properties even after continuous heating in air at 525° C. for 50 hours. The solar selective coatings of the present invention exhibit high hardness, high oxidation resistance, chemical inertness and stable microstructure.

An optical method for measuring the temperature of a substrate material with a temperature dependent band edge. In this method both the position and the width of the knee of the band edge spectrum of the substrate are used to determine temperature. The width of the knee is used to correct for the spurious shifts in the position of the knee caused by: (i) thin film interference in a deposited layer on the substrate; (ii) anisotropic scattering at the back of the substrate; (iii) the spectral variation in the absorptance of deposited layers that absorb in the vicinity of the band edge of the substrate; and (iv) the spectral dependence in the optical response of the wavelength selective detection system used to obtain the band edge spectrum of the substrate. The adjusted position of the knee is used to calculate the substrate temperature from a predetermined calibration curve. This algorithm is suitable for real-time applications as the information needed to correct the knee position is obtained from the spectrum itself. Using a model for the temperature dependent shape of the absorption edge in GaAs and InP, the effect of substrate thickness and the optical geometry of the method used to determine the band edge spectrum, are incorporated into the calibration curve.

In a micro-bridge structure in which a temperature detecting portion (diaphragm) including a bolometer thin film is supported by a supporting portion in a state floated from a circuit substrate, a reflective film reflecting a THz wave is formed on the circuit substrate, an absorbing film absorbing the THz wave is formed on the temperature detecting portion, and an optical resonance structure is formed by the reflective film and temperature detecting portion. A gap between the reflective film and temperature detecting portion measures approximately ¼ infrared wavelength (e.g., 1.5 to 2.5 μm). Sheet resistance of the temperature detecting portion is set in a range in which an absorptance of the THz wave becomes a predetermined value or above on the basis of the THz wave (approximately 10-100 Ω/sq.). The absorptance of the THz wave is drastically improved while using the structure and manufacturing technique of a bolometer-type infrared detector.

A light emitting device, includes: a light source; a first wavelength conversion unit absorbing a light-source light radiated by the light source and radiating a first light, a wavelength of the first light being different from a wavelength of the light-source light; and a second wavelength conversion unit dispersedly provided in the first wavelength conversion unit, the second wavelength conversion unit absorbing the light-source light and radiating a second light. An absorptance of the light-source light in the second wavelength conversion unit is higher than an absorptance of the light-source light in the first wavelength conversion unit. A wavelength of the second light is different from the wavelength of the light-source light and different from the wavelength of the first light.

The invention discloses a high-temperature glaze coating, a preparation method thereof, a binder and a using method of the coating, and aims at solving the problems of poor high-temperature resistance, low emissivity and absorptivity in a high-temperature zone, instability, and easiness of attenuation of the existing far-infrared energy-saving coating. The high-temperature glaze coating has the characteristics of good radiation heat transfer effect, high external blackness (the emissivity is greater than 0.95) and the like, and has the advantages of stable emissivity and absorptivity, non-attenuation performance and long service life in a long-term use process. Meanwhile, the coating can be tightly combined with a basal body by matching with the binder disclosed by the invention; the adhesive force is increased; a glazed ceramic polymer can be formed on the basal body after high-temperature sintering; the high-temperature glaze coating has the advantages of hardness, abrasive resistance, and long service life, and does not fall off; and the coating disclosed by the invention can also evenly coat the surface which cannot be covered by general coatings.

An X-ray absorptance map associated with an object to be examined is generated on the basis of scanogram data obtained from a predetermined direction of the object, and imaging conditions are determined on the basis of the absorptance map. Before tomography, an index representing a radiation dose in the execution of scan in accordance with the imaging conditions is calculated and displayed, together with the imaging conditions. Every time the imaging conditions are changed, an index representing a radiation dose is calculated and displayed. Tomography is executed in accordance with the finally determined imaging conditions. This makes it possible to reduce the radiation dose to the object and obtain a tomographic image with high quality.

The invention discloses a nanometer titanium dioxide photocatalyst responding visible light with high absorbance and a wide wavelength range on the visible light. The photocatalyst is characterized in that a mass ratio of nanometer TiO2 to active carbon is 1:5-15; a mass ratio of metal silver to the nanometer TiO2 is 0.5-2:100; and a mass ratio of metal copper or iron or rhodium or platinum or gold or tin to the nanometer TiO2 is 0-2:100. The method for preparing the photocatalyst comprises the following steps: preparing a titanium ester solution and a soluble metal salt solution to be mixed and evenly stirred; evenly loading TiO2 particles and metal ions onto the surface of the active carbon by a sol-gel method; and carrying out thermal treatment under the protection of inert gases at a temperature of between 300 and 600 DEG C for 2 to 6 hours so as to prepare the metal doped and active carbon loaded anatase type TiO2 photocatalyst. The photocatalyst and the method have a simple process; compared with the prior loading type visible light photocatalyst, the prepared product can sufficiently utilize sunlight, has the absorbance to the visible light reaching about 85 percent and wide wavelength range, can be industrially applied, has the characteristics of energy conservation, environmental protection and the like; meanwhile, due to larger particles of the active carbon, recycle of the photocatalyst is convenient, and treatment cost is reduced.

The invention provides a non-vacuum solar spectrum selective absorption film and a preparation method thereof. The absorption film comprises a stainless steel or copper substrate which is successivelyprovided with a titanium-aluminum film, a titanium-aluminum-nitrogen film, a titanium-aluminum-oxygen-nitrogen film and a titanium-aluminum-oxygen film from inside to outside, wherein the films are prepared by adopting multi-arc ion plating; a target material adopts titanium-aluminum alloy target of which the atomic ratio of titanium to aluminum is 50:50; and the content of nitrogen and/or oxygenin the films is controlled by controlling the flow of argon, nitrogen and oxygen in the atmosphere of multi-arc ion plating. The method comprises: (1) selecting and cleaning a substrate material; (2)baking the substrate material in a vacuum sputtering chamber of a multi-target compound coating machine; (3) performing argon-ion bombardment on the surface of the substrate material; (4) coating thesubstrate material; and (5) performing annealing treatment. The absorption film has the advantages of high absorptivity alpha in a solar spectral range (0.3 to 2.5 microns), low emissivity epsilon inan infrared region (2 to 50 microns) and the characteristic of resisting high-temperature oxidation, thereby meeting the requirements of solar high-temperature utilization.

The invention provides an optical structure tool for a stray light resisting test of a star sensor and a testing method. A light blocking barrel equipped with a planar coating with high absorptivity and extinction cones inside is arranged, a digital display variable diaphragm and stray light eliminating diaphragms are mounted in the light blocking barrel, and a light transmitting aperture is formed in the light output direction of the tool, or a solar battery cell and a high-precision optical reflector are mounted in the light output direction of the tool. The area of an output light spot is controlled by adjusting the diameter of the digital display variable diaphragm in the light blocking barrel, light spots outside a light hood of the star sensor can be prevented from irradiating test background space, meanwhile, the stray light caused by the diffraction phenomenon is reduced by means of the stray light eliminating diaphragms, so that the light interference of the background environment is reduced in the stray light testing process, and the testing precision of the star sensor in a darkroom environment is improved.

The invention relates to a preparation method of a BiFeO3 material, a BiFeO3/TiO2 composite film and an application thereof. The preparation method of the BiFeO3 material comprises the steps: firstly, dissolving bismuth nitrate and ferric nitrate into ethylene glycol monomethyl ether to obtain a solution I; then, dissolving citric acid into the solution I to obtain a solution II; and next, regulating the PH value of the solution II to 3-5 by using acetic acid to obtain a BiFeO3 sol. The BiFeO3/TiO2 composite film comprises a substrate, wherein the substrate is coated with double layers of films which are respectively a BiFeO3 film layer and a TiO2 film layer. The absorptivity of the BiFeO3/TiO2 composite film on a visible light wave band is greatly improved through the absorption spectrum test and theoretical analysis on the double layers of films. The BiFeO3/TiO2 composite film is applied to the preparation of photovoltaic materials, solar cells, orientation controlled photoelectric functional device materials and visible light catalysis sterilization materials.

A photodiode for an image sensor capable of reducing reflection of light incident onto the photodiode and effectively absorbing transmitted light and a method of manufacturing the same are provided. In the photodiode for the image sensor, a silicon concavo-convex surface with a nano-thickness is formed by forming silicon oxide (SiO, x=0.5-1.5) layer on a silicon substrate and treating the silicon oxide layer with heat. A photodiode region is formed under the silicon layer having convexes and concaves. In this case, light absorptance increases because light reflected on the silicon concavo-convex surface is reincident onto another convex or concave. Therefore, an effective depth of the photodiode is larger than that of a planar photodiode, and accordingly, quantum efficiency of the photodiode increases.

Provided is a broadband photomixer technology that is a core to generate continuous frequency variable and pulsed terahertz waves. It is possible to enhance light absorptance by applying the transmittance characteristic of a 2D light crystal structure and it is possible to increase the generation efficiency of terahertz waves accordingly. Moreover, it is possible to implement a wide area array type terahertz photomixer by applying an interdigit structure and spatially properly arranging a light crystal structure having various cycles. Accordingly, it is possible to solve difficulty in thermal characteristic and light alignment by mitigating the high light density of a light absorption unit and low photoelectric conversion efficiency is drastically improved. In addition, the radiation pattern of terahertz waves may be electrically controlled through the present invention.

The invention provides a hydrosol for preparing a solar photo-thermal conversion absorption film. Water is used as a solvent in the hydrosol; a transition metallic M salt, an aluminum salt and a chelating agent are used as raw materials; the transition metallic M salt and the aluminum salt are respectively prepared into an M sol and an Al2O3 sol together with the chelating agent; and the M sol and the Al2O3 sol are mixed and added with a wetting agent to form an M-Al2O3 mixed sol, namely the hydrosol. The M-Al2O3 mixed sol for preparing the absorption film is prepared by using the environment-friendly water as the solvent; the sol preparation method is simple, feasible, easily obtainable in raw materials and low in cost; after the M-Al2O3 mixed sol added with the wetting agent forms a film on a metal substrate, an M-Al2O3 absorption layer can be directly obtained by thermal treatment under inert atmosphere; the film preparation process is simple, convenient and low in equipment requirement, and has no pollution to the environment; and the solar absorption rate of the prepared single-layer M-Al2O3 film can reach 0.86, and the emissivity of the film is only 0.03.

A solar collector has an opaque cover heated by solar energy. Heat flows from the opaque cover by conduction, convection, and infrared emittance across a gap within an at least substantially airtight enclosure to an absorber containing a working fluid. The exterior surface of the opaque cover has high solar energy absorptance and the interior surface has high infrared emittance. The exterior surface preferably has low infrared emittance. In one embodiment, fully wetted surface geometry permits direct and reflected infrared absorption by the absorber. The opaque cover eliminates the weight, cost and other shortcomings of glass. A hollow continuous side wall with rounded corners provides an embodiment that is robust yet economical, that is easy to manufacture and seal, that permits a reduced thickness of the opaque cover and mitigates the destructive potential of severe winds, and that can withstand the compressive forces experienced by an evacuated solar collector.

An annealing method irradiates a target object, having a film formed on its surface, with a laser beam to perform an annealing process to the target object. The surface of the target object is irradiated with the laser beam obliquely at an incident angle that is determined to achieve an improved laser absorptance of the film.

The invention discloses a porous graphene film prepared by a laser processing method, and a preparation method and application thereof, and belongs to the technical field of material preparation. Thelaser processing method is utilized to process a polyimide film material, the polyimide material is subjected to high-temperature decomposition through photothermal effect of laser to prepare the laser-induced graphene (LIG), and meanwhile, gas escapes in the reaction process so that the prepared LIG has a porous structure. The porous structure of the LIG is favorable for reflecting incident sunlight for multiple times, so that the optical path is increased, and the absorptivity of the sunlight is improved. After LIG is subjected to oxygen plasma treatment, the surface of LIG is more hydrophilic, and the LIG can be in full contact with liquid water. Besides, the LIG is benefited from a porous structure, high light absorption rate and good photothermal conversion capability, and the film can be used for a solar seawater desalination device to desalinate seawater. The film can also be used for an evaporative humidifier to improve the environment humidity.

A multilayer solar selective coating on metallic and non-metallic substrates suitable for high temperature solar thermal power applications. The optimized solar selective coating of the present invention on stainless steel substrate exhibits absorptance of 0.954 and emittance of 0.07. A five layer coating is deposited using the sputtering process, and includes tungsten (W), titanium aluminum nitride (TiAlN), titanium aluminum silicon nitride (TiAlSiN), titanium aluminum silicon oxy-nitride (TiAlSiON), and titanium aluminum silicon oxide (TiAlSiO) layers. The first layer (W) acts an infrared reflector, the second layer (TiAlN), the third layer (TiAlSiN) and the fourth layer (TiAlSiON) act as the absorber layer and the fifth layer (TiAlSiO) acts as the anti-reflection layer. The high-temperature solar selective coating exhibits average emittance of 0.10 at 400° C. on stainless steel substrate in the wavelength range of 2.5-25 μm, thus is suitable for applications in concentrating collectors like evacuated receiver tubes for solar thermal power generation.