39results about How to "Good spectral selectivity" patented technology

The invention discloses a super-hydrophobic daytime passive radiation refrigeration porous membrane and a preparation method thereof, and the preparation method comprises the following steps: (1) dispersing inorganic nanoparticles in water to prepare an inorganic nanoparticle dispersion liquid; (2) adding a fluorine-containing group modifier into the inorganic nanoparticle dispersion liquid, magnetically conducting stirring at 20-40 DEG C for 15-24 hours, and modifying the inorganic nanoparticles to obtain a modified inorganic nanoparticle dispersion liquid, wherein the particle size distribution of the modified inorganic nanoparticles is 50-1000 nm; (3) dissolving an organic polymer in an organic solvent to form an organic polymer solution; (4) adding the modified inorganic nanoparticle dispersion liquid into the organic polymer solution, and uniformly conducting dispersing to form a precursor solution; and (5) coating a base material with the precursor solution, and conducting drying to obtain the super-hydrophobic daytime passive radiation refrigeration porous membrane. The preparation method disclosed by the invention is simple and low in cost, and the prepared daytime passive radiation refrigeration porous membrane has super-hydrophobic self-cleaning capability.

Disclosed is a spectrally selective solar absorbing coating and a method for making same. The spectrally selective solar absorbing coating includes a multilayer stack including, from the substrate to the air interface: substrate (1), infrared reflective layer (2), barrier layer (3), composite absorbing layer (4) consisting of metal absorbing sublayer (4.1), metal nitride absorbing sublayer (4.2), and metal oxynitride absorbing sublayer (4.3), and antireflective layer (5). Therefore, the solar absorbing coating has good high and low temperature cycle stability and superior spectrum selectivity, with a steep transition zone between solar absorption and infrared reflection zones. It has a relatively high absorptance α>95%, and a low thermal emissivity ∈≦4%, PC (performance criterion)=−0.3. The solar absorbing multilayer stack can be obtained by reactively magnetron sputtering the metal target in argon or other inert gas with some amounts of gas containing oxygen or nitrogen or their combination.

A laser device for intra-cavity frequency conversion, in particular, for the second harmonic generation, the device comprising a laser cavity, formed by the first and the second laser cavity end reflectors wherein the said laser cavity end reflectors are highly reflective for the radiation about the laser fundamental frequency and as such provide for a predetermined level of circulating inside the cavity fundamental frequency power; an active medium provided within the said laser cavity; at least one non-linear crystal, in particular, for the second harmonic generation provided within the same laser cavity; tuning means adapted for tuning at least one of laser cavity end reflectors; wherein at least one of the laser cavity end reflectors comprises an interferometric layout providing spectrally selective reflection for the radiation about the laser fundamental frequency with the value of reflectivity nearly to 100% within a spectral range close to the free spectrum range of the laser cavity and with a sufficiently lower reflectivity outside the above spectral range such that the laser cavity restricts the spectrum of the laser radiation to a single longitudinal mode.

The invention discloses a self-powered photoelectric detection structure based on graphene-gallium oxide phase junction, a corresponding preparation method and a photoelectric detector. The structurecomprises a substrate, gallium oxide phase junction nano columns formed on the substrate and a graphene film formed on the gallium oxide phase junction nano columns. The method comprises the steps ofgenerating gallium oxide phase junction nano columns on the substrate through hydrothermal, annealing and high temperature annealing, and transferring and forming a graphene film on the gallium oxidephase junction nano columns. The structure has the advantages of simple preparation process, low cost, easy mass production and the like. The photoelectric detector has the characteristics of self-power supply and good spectral selectivity, and has the properties such as high responsiveness and high sensitivity to sunblind ultraviolet light.

Embodiments of wavelength tunable lasers are disclosed. The wavelength tunable lasers include thermo-optic organic material that has an index of refraction that can quickly vary in response to changes in temperature. By controlling the temperature in the thermo-optic organic material through the use of heaters or coolers, the wavelength tunable lasers and the integrated optical components can be quickly and selectively tuned over a broad range of wavelengths with high spectral selectivity.

The invention relates to a method for detecting the polarization spectrum characteristic of light beams. The prior art system is complicated and the sensitivity of spectral measurement is low, and it is impossible to realize the detection of the polarization state distribution of the light beam and the simultaneous detection of polarization and spectral characteristics. The invention utilizes a flexible polarizing film to make a conical light beam polarization detection element, and a flat electro-optic crystal coated with a high-reflection film on both sides is provided with parallel light-transmitting electrode plates, which are connected to an adjustable power supply. Constitute a microcavity line scanning element; the incident beam passes through the conical beam polarization state detection element, the microcavity line scanning element, the beam converging element and the area array photodetector in turn, and the area array photodetector collects spectral information and The light spot of the polarization distribution is obtained, and then the polarization spectral characteristics of the beam are obtained. The method of the invention is simple and flexible, has low structural positioning requirements, simultaneously realizes high-precision spectrum measurement and beam transverse polarization state distribution analysis, has high system reliability and stability, and has strong operability.

The invention belongs to the photoelectric device technology field and especially discloses a manufacturing method of a two-dimensional ordered TiO2 nanometer well film and an application in a self-energized photoelectric device. In the invention, firstly, a two-dimensional ordered TiO2 nanometer well film is manufactured; and then the manufactured TiO2 nanometer well film is taken as a substrate so as to manufacture a heterojunction compound with inorganic-substance layered NiO organic semiconductor polyaniline; and a self-energized photoelectric detector is constructed. The method comprises the following steps of anodic oxidation, physical stripping, heating calcinations, low temperature hydrothermal treatment, in situ polymerization and the like. In the invention, a complex and expensive manufacturing technology of the photoelectric device is avoided and rapid construction of a large-scale device can be realized; a photovoltaic effect of a p-n junction is used, under zero-bias driving, photon-generated carriers are rapidly separated under a built-in potential effect, self-energized performance of the device is realized and a light current is stable and a response speed is fast; and for ultraviolet light, good selection performance is possessed, and the photoelectric detector can be served as an energy-saving high frequency detector and a high-frequency photoelectric converter and can be applied in the fields of optical communication, military, medical treatment, photoelectric storage and the like.

The invention discloses a boro-isoindole fluorescent dye and a preparation method and applications thereof. The structure of the boro-isoindole fluorescent dye is represented by the formula (I). The provided boro-isoindole fluorescent dye has the advantages of good spectral selectivity, excellent fluorescence quantum yield, and good solubility, can carry out derivation through Knoevenagel reactions, has high water solubility and a good cell penetrating performance after salt forming, and can be applied to imaging for positioning mitochondria at the same time.

The invention discloses a preparation method of transparent heat insulation and cooling coating for an electric vehicle hood. The preparation method comprises the following steps: adding deionized water in waterborne polyurethane resin, uniformly stirring at high speed to obtain a film-forming agent, mixing the film-forming agent with nanometer tin antimony oxide waterborne slurry, nanometer indium tin oxide waterborne slurry and nanometer lanthanum hexaboride heat insulation slurry and the cladding modified hollow glass beads, stirring at high speed, adding auxiliaries, ultrasonically dispersing after quickly stirring, leaving to stand to defoam and then filtering to obtain the transparent heat insulation and cooling coating. Since the titanium dioxide is high in sunlight reflectivity, alayer of titanium dioxide film is adhered on the surface of the hollow glass beads, the dispersion effect of the hollow glass beads in the waterborne coating can be improved, and the capacity of reflecting the solar radiation is enhanced at the same time, and then the aim of cooling is achieved.

The invention provides coated aluminum powder. The coated aluminum powder is prepared from the following raw material components in parts by mass: 10-26 parts of aluminum powder, 5-14 parts of a coloring pigment, 20-50 parts of a solvent, 0.1-1 parts of an etching substance, and 0.04-0.1 parts of an auxiliary agent, wherein the aluminum powder is oily non-floating aluminum powder, the coloring pigment is one of phthalocyanine blue, cobalt blue, malachite green, carbon black, bright red, medium chrome yellow and permanent yellow, the solvent is at least one of xylene, butyl ester, ethanol, 120 # solvent oil and DMF, the etching substance is one of oleic acid and acetic acid, and the auxiliary agent is at least one of a silane coupling agent and a dispersing agent. According to the invention, the coated aluminum powder can be well dispersed in the coating and has the advantages of being low in brightness, adjustable in color and emissivity and the like, and the preparation method is simple in process, low in price, suitable for mass production and capable of being applied to military protection, civil art coating, building coating material and the like.

The invention relates to a medium-high-temperature solar selective absorbing coating and a preparation method thereof. The medium-high-temperature solar selective absorbing coating comprises an existing metal substrate. The medium-high-temperature solar selective absorbing coating is characterized in that the metal substrate comprises an infrared reflecting layer, an absorbing layer and an antireflection layer from bottom to top; the infrared reflecting layer is a coating of any one of Al, Au, Ag and Ni, the absorbing layer sequentially comprises a TiN film and a TiCrN film from bottom to top,and the antireflection layer sequentially comprises a Cr2O3 film, an AlN film and an Al2O3 film from bottom to top; and film coating is carried out through a magnetron sputtering method. The medium-high-temperature solar selective absorbing coating has the beneficial effects that 1, the prepared coating has the characteristics of high absorbing efficiency, low emissivity and good heat stability;2, the ratio of the solar spectrum emissivity alpha to the emissivity epsilon (T) is high, and the coating is suitable for being applied to medium-high temperature of 200 DEG C or above; and 3, the manufacturing process is simple and convenient.

The invention discloses a graphene-based selective absorption film system and an absorbing layer preparation method thereof. The preparation method of the graphene absorbing layer in the film system is mixed solution coating and comprises the steps that graphite power is subjected to oxidation stripping to obtain an oxidized graphene aqueous solution; the oxidized graphene aqueous solution is mixed with a lower surface tension solution to obtain a mixed solution; the mixed solution is coated to the surface of an infrared reflecting layer, so that an oxidized graphene absorbing layer is obtained; and the oxidized graphene absorbing layer is subjected to reduction treatment to obtain the graphene absorbing layer. The graphene absorbing layer has good refractive index and extinction coefficient, so that the excellent spectral selectivity of the graphene-based selective absorption film system is ensured, and the photo-thermal utilization efficiency of the selective absorption surface is improved. Meanwhile, the thickness of the graphene layer is changed to adjust an optical band gap of the film system, and the graphene-based selective absorption film system further has a solar energy utilization system which has stability for a long time at high temperature, is matched with the optical band gap and can be widely applied to low temperature to high temperature.

The invention provides a photovoltaic module which comprises a photovoltaic cell and a first combined film structure, wherein the first combined film structure is located on the back surface of the photovoltaic cell, the first combined film structure comprises a plurality of transparent film layers, and at least two first reflection interfaces are formed on the plurality of transparent film layers; the ultraviolet light is reflected from the two first reflection interfaces to form the first reflection light and the second reflection light which deviate from the photovoltaic cell, and the first reflection light and the second reflection light can interfere with each other in a constructive manner, so that the reflection of the ultraviolet light is selectively improved. The first combined film structure provided by the invention is good in ultraviolet resistance and low in cost. Therefore, the photovoltaic module using the first combined film structure is good in ultraviolet resistance, low in cost, good in flexibility and wide in application range, and can be applied to automobiles, ships, color steel tile roofs, building curtain walls and the like.

The invention provides a BaTiO3 thin film ultraviolet detector and a preparation method thereof, and particularly relates to a BaTiO3 thin film with a forbidden band width of 3.9-4.4 eV. The detectorcomprises a substrate, a BaTiO3 film growing on the upper surface of the substrate, and an interdigital electrode layer compounded on the BaTiO3 film, the forbidden band width of the BaTiO3 thin filmis 3.9 to 4.4 eV; the grain size of the BaTiO3 thin film ranges from 0.01 nm to 30 nm; the thickness of the BaTiO3 thin film ranges from 50 nm to 500 nm; and the light absorption cut-off edge of the BaTiO3 thin film is 280 to 320 nm. The BaTiO3 film prepared by the method has the characteristics of small grain size, wide energy gap, absorption cutoff edge of 280-320 nm and the like, so that the detection wavelength corresponding to a BaTiO3 ultraviolet detector is 280-320 nm, the BaTiO3 film is an excellent UVB photoelectric detection material, detection of BaTiO3 to the UVB waveband is realized, and application of the BaTiO3 film in the field of UVB ultraviolet detectors is broadened.