68results about How to "Reduce radiative heat loss" patented technology

Articles of furniture with a system of heating and cooling that can be integrated into a building environmental control network are provided. The heating / cooling system of the article has surfaces of a porous or non-porous, moisture-permeable material allowing convective and evaporative heat exchange from the body surface to the environment. The material covers a plenum that has reflective surfaces to reduce radiant losses and low-wattage fans to circulate air that convectively cools the occupant. Resistance heating may be incorporated at key occupant contact areas in the seat and backrest. Temperature, occupancy and other sensors can be incorporated. A control interface controls the actions of the heating / cooling system of the article and can interact with a network server to transmit measurements of environmental temperatures and occupant selection of control settings that are useful for control of the building's indoor environment.

A multi-layer flexible insulation (I) comprises a series of layers which include a pair of closed-cell insulation sheets (10,12) made of multicellular plastic film (i.e. closed cell air bubbles or bubble-pack) and laminated on both sides of a thin white polyethylene film (14), a pair of aluminum foil layers or films (16,18) adhesively mounted on the outer surfaces of the bubble-pack insulation sheets (10,12), and a pair of thin clear polyester layers (20,22) provided on the outer surfaces of the aluminum layers. The aluminum layers (16,18) are vapor deposited on the polyester layers (20,22) and are assembled to the hot bubble-pack insulation sheets (10,12) while the latter are cooled. The bubble-pack sheets (10,12) are then adhered to the central polyethylene film (14) with a hot melt glue. If the polyester (20,22) is highly smooth, the aluminum (16,18) can be deposited thereon in a uniform state thereby providing a high reflectivity, low emissivity, laminate. The outer polyester coatings (20,22) also protect the aluminum layers (16,18) such as to prevent any aluminum from rubbing off the insulation (I) and also prevent the aluminum layers (16,18) from oxidizing. Furthermore, the polyester coatings (20,22) provide an hygiene barrier for the insulation (I).

The invention provides receivers which can be used to heat a working fluid to high temperature. In preferred embodiments, concentrated solar radiation is received and converted to heat at varying depths in the receiver such that multiple layers of surface are used to heat the working fluid. In addition, the depth-loading configuration helps to trap received heat to reduce radiant thermal loss.

A multi-layer flexible insulation (I) comprises a series of layers which include a pair of closed-cell insulation sheets (10,12) made of multicellular plastic film (i.e. closed cell air bubbles or bubble-pack) and laminated on both sides of a thin white polyethylene film (14), a pair of aluminum foil layers or films (16,18) adhesively mounted on the outer surfaces of the bubble-pack insulation sheets (10,12), and a pair of thin clear polyester layers (20,22) provided on the outer surfaces of the aluminum layers. The aluminum layers (16,18) are vapor deposited on the polyester layers (20,22) and are assembled to the hot bubble-pack insulation sheets (10,12) while the latter are cooled. The bubble-pack sheets (10,12) are then adhered to the central polyethylene film (14) with a hot melt glue. If the polyester (20,22) is highly smooth, the aluminum (16,18) can be deposited thereon in a uniform state thereby providing a high reflectivity, low emissivity, laminate. The outer polyester coatings (20,22) also protect the aluminum layers (16,18) such as to prevent any aluminum from rubbing off the insulation (I) and also prevent the aluminum layers (16,18) from oxidizing. Furthermore, the polyester coatings (20,22) provide an hygiene barrier for the insulation (I).

The invention relates to an aircraft side fairing, with a component (9) in the form of individual hollow chambers (12, 13, 14) which are arranged essentially in a preferably curved plane and are arranged between two cover layers (1, 2), wherein a gastight film which completely encases the component (9) with the hollow chambers (12, 13, 14) is provided and, after application of a vacuum to evacuate the hollow chambers (12, 13, 14), surrounds the component (9) with the hollow chambers in a gastight manner.

The invention provides a solar energy and wind energy complementary-driving multiple-effect salifarous water desalting device based on disk type light condensation. The device can achieve effective switchover between solar energy driving and wind energy driving through structure change of a disk type light condenser. The lower half part of a stirring blade is sprayed into black, the stirring bladeis arranged in an evaporating cavity and is connected with the disk type light condenser through a rotating shaft and a rotating arm, a hemispherical glass shell is arranged at the bottom of the evaporating cavity, a secondary parabolic light condenser is arranged outside the hemispherical glass shell, a focal spot of the parabolic light condenser is arranged at the hemispherical glass shell, thehemispherical glass shell is arranged at the focal spot position of the disk type light condenser, salifarous water containing a lot of black porous light absorption particles is accommodated in theevaporating cavity, high-density light energy formed by reflection of the light condenser is directly absorbed, and the salifarous water is heated and evaporated to generate fresh water on the lower surfaces of condensation disks. The device utilizes the characteristic that heated water vapor floats and rises upwards, so that a plurality of the water accommodating condensation disks are distributed in the water vapor floating and rising direction, latent heat released by water vapor condensation is recycled for many time, and graded and repeated utilization of heat contained in the water vaporis achieved.

A multi-layer flexible insulation (I) comprises a series of layers which include a pair of closed-cell insulation sheets (10,12) made of multicellular plastic film (i.e. closed cell air bubbles or bubble-pack) and laminated on both sides of a thin white polyethylene film (14), a pair of aluminum foil layers or films (16,18) adhesively mounted on the outer surfaces of the bubble-pack insulation sheets (10,12), and a pair of thin clear polyester layers (20,22) provided on the outer surfaces of the aluminum layers. The aluminum layers (16,18) are vapor deposited on the polyester layers (20,22) and are assembled to the hot bubble-pack insulation sheets (10,12) while the latter are cooled. The bubble-pack sheets (10,12) are then adhered to the central polyethylene film (14) with a hot melt glue. If the polyester (20,22) is highly smooth, the aluminum (16,18) can be deposited thereon in a uniform state thereby providing a high reflectivity, low emissivity, laminate. The outer polyester coatings (20,22) also protect the aluminum layers (16,18) such as to prevent any aluminum from rubbing off the insulation (I) and also prevent the aluminum layers (16,18) from oxidizing. Furthermore, the polyester coatings (20,22) provide an hygiene barrier for the insulation (I).

A reaction chamber system, and related devices and methods for use in the system, are provided in which reduced power consumption can be achieved by providing a thin layer of gold on one or more components inside a reaction chamber. The reaction chamber system can be used for chemical vapor deposition. The gold coating should be maintained to a thickness of at least about 0.1 microns, and more preferably about 0.5 to 3.0 microns, to provide a suitable emissivity inside the reaction chamber, and thus reduce heat losses.

The invention discloses a glass tube bundle and porous medium composite structure solar absorber which comprises a solar absorber shell, wherein a quartz glass window is formed in one end of the solar absorber shell, and a medium outlet is formed in the other end of the solar absorber shell; the solar absorber shell and the quartz glass window are connected into a whole, and a cavity is formed between the solar absorber shell and the quartz glass window; glass tube bundles and porous media are sequentially arranged inside the cavity along the solar incident direction; a preheating channel is formed among the solar absorber shell, the glass tube bundles and the porous media; a first medium inlet is formed in one end of the preheating channel; and after preheated in the preheating channel, the media converge sunlight at the second medium inlet so as to enter the glass tube bundles. Because the glass tube bundles are small in solar absorption and small in external radiation energy, the thermal efficiency of the system is improved. Meanwhile, the incident sunlight is transmitted to the porous medium by the glass tube bundles, so that medium distribution is matched with sunlight flow density, while the porous medium is mainly capable of converting solar radiation energy into internal energy of working media; and therefore, the problem that the existing porous medium solar absorber is low in thermal efficiency and reliability is effectively solved.

The invention discloses a rare earth fused-salt electrolysis cell for producing rare earth metals and alloys by using a liquid cathode. The rare earth fused-salt electrolysis cell mainly comprises an electrolysis cell body, an anode and the liquid cathode; the anode and the cathode are provided with horizontal planes parallel to and facing each other; the anode is vertically inserted in the electrolysis cell body; the liquid cathode is a liquid metal electrolyzed at the bottom; a tungsten plate is inlaid in the internal bottom of the electrolysis cell body; a molybdenum plate or a niobium plate can be taken as a cathode bottom plate or a rare earth metal catcher for an electrolytic product separated out on the cathode. The rare earth fused-salt electrolysis cell for producing rare earth metals and alloys by using the liquid cathode has the advantages of high current efficiency, low radiant heat losses, high anode utilization rate, long electrolysis cell service life and low investment of the electrolysis cell body; the single plant capacity can reach above 100 KA, the energy consumption per unit product is greatly reduced, and produced products are stable in quality, low in production cost and relatively closed.

The invention provides a device and method for measuring the specific heat capacity and phase change latent heat of a substance. The device comprises a calorimeter component and a sample temperature control component. The calorimeter component comprises a calorimeter. A magnetic stirrer used for stirring a calorimetric liquid in the calorimeter is arranged at the bottom of the calorimeter. A temperature difference thermocouple and a first temperature sensor are arranged in the calorimeter. The sample temperature control component is located above the calorimeter. The sample temperature controlcomponent comprises a thermostatic aluminum block. A platinum resistance thermometer and a tested sample are arranged in the thermostatic aluminum block. A second temperature sensor is arranged on the tested sample. The calorimetric liquid is ethylene glycol. The calorimeter is in a double-layered sleeve structure. According to the invention, the device can accurately measure the specific heat capacity of a solid and liquid and the phase change latent heat of a solid-liquid phase change material; the stability of the device is great; a wide temperature range can be measured; and the device can be used for measuring the specific heat capacity and phase change latent heat of materials in industry and scientific research, and can be used for teaching experiments of energy and power related professional courses.

The invention discloses a porous material solar energy air heat-collecting device which comprises a transparent cover plate, a frame, a porous material heat absorption body, a heat absorption baseplate arranged below the transparent cover plate, a porous material heat-exchange enhancement element, a back plate, an air inlet and an air outlet, wherein the upper surface of the heat absorption baseplate is attached with the surface of the porous material heat absorption body, and the lower surface thereof is attached with the base surface of the porous material integrated heat-exchange enhancement element; an air channel for air ventilation is remained between the heat absorption baseplate and the back plate; the outer side of the frame is attached with a box body made of a heat insulation material; air flows into a heat collector from an heat collector inlet under the driving of a fan, flows on the heat-exchange enhancement surface and carries out high-efficiency heat exchange with the heat-exchange enhancement surface to obtain hot air; and finally, the heated hot air flows out of a heat collector outlet. The heat-collecting device can be adopted for collecting solar energy with high efficiency to obtain the hot air, thereby satisfying the requirements for building heating as well as drying of rural grains and commercial crops.

The invention relates to a slot type light gathering type solar vacuum heat collecting pipe. The slot type light gathering type solar vacuum heat collecting pipe comprises an outer glass cover pipe and an inner heat absorbing pipe. An inner pipe coating is arranged on the outer cylindrical face of the inner heat absorbing pipe. A cavity between the outer glass cover pipe and the inner heat absorbing pipe is vacuum annular space. A heat shielding plate is arranged in the vacuum annular space. The side face, corresponding to the inner heat absorbing pipe, of the heat shielding plate is a reflection face, and the side face, corresponding to the outer glass cover plate, of the heat shielding plate is an absorption face. The inner surface of the heat shielding plate has the properties of high reflectivity and low emissivity in an infrared band, the outer surface of the heat shielding plate is coated with a selective absorption coating and has the properties of high absorptivity in the solar radiation wave band of 0.2-3 microns and low emissivity in the infrared wave band larger than 3 microns. The external radiation heat loss of the inner pipe of the vacuum heat collecting pipe under the medium-high temperature heat collecting situation can be greatly reduced, and the heat collecting efficiency is improved.

A glass-cover-free tubular solar thermal collector relates to a solar thermal collector, and a problem that a glass cover of the solar thermal collector cracks due to the fact that thermal expansion degrees of a metal material and the glass cover of a tubular thermal absorber are different is solved. A light enclosing cavity is made of a metal material, a heat preservation layer is wrapped on an outer wall of the light enclosing cavity, and the tubular thermal absorber is arranged in the light enclosing cavity and made of the metal material. A light-transmitting port is arranged on the top portion of the light enclosing cavity, an optical window is arranged at the light-transmitting port, and two ends of the light enclosing cavity are connected with the tubular thermal absorber in mechanical mode through metal sealing connecting joints with a function of reducing thermal strain respectively. The axial thermal expansion difference of the light enclosing cavity and the tubular thermal absorber is offset through wave pitch changes of a corrugated metal connecting sealing joint, and the problem that the glass cover is prone to crack, and the glass cover, the tubular thermal absorber and the metal connecting sealing joint of the traditional tubular thermal absorber are hard to weld is solved.

The invention relates to a turbulent micro burner preheated by exhaust gas. The turbulent micro burner comprises a combustion chamber, a gas inlet chamber, an exhaust chamber, a gas inlet pipe and an exhaust pipe, wherein the combustion chamber, the gas inlet chamber and the exhaust chamber are all flat cylinders; the gas inlet pipe and the exhaust pipe are cylinders; the combustion chamber is arranged in the gas inlet chamber; the top of the combustion chamber is communicated with the inner surface of the top of the gas inlet chamber; the combustion chamber is provided with three combustion chamber inlets which are formed in the side surfaces of the combustion chamber respectively; every two adjacent combustion chamber inlets are spaced at an interval of one third of an arc; an included angle formed between an axis of each combustion chamber inlet and a round edge tangent line of the combustion chamber is 30 degrees; a combustion chamber exhaust port is formed in the center of a top section of the combustion chamber and is round, and a circle center of the combustion chamber exhaust port is located in an axis of the combustion chamber; the gas inlet pipe is arranged in a center of the lower surface of the gas inlet chamber, and a section area is equal to that of the combustion chamber exhaust port; the gas inlet chamber is arranged in the exhaust chamber; the gas inlet chamber and the exhaust chamber are connected through fixing supporting columns; the exhaust pipe is arranged in the center of the lower surface of the exhaust chamber, and the section area is larger than that of the gas inlet pipe; and a layer of a heat insulation material is arranged on the outer layer of the exhaust chamber and the outer layer of the exhaust pipe.

The invention discloses a two-stage heat absorber. The two-stage heat absorber comprises a cavity, wherein the cavity is divided into a low-temperature heat absorbing area and a high-temperature heat absorbing area, the high-temperature heat absorbing area is cylindrical, one end of the high-temperature heat absorbing area is open, a working medium outlet is formed in the bottom end of the cavity, the low-temperature heat absorbing area is of a circular truncated cone structure, an interlayer channel is formed in the inner wall of the cavity, an air working medium passes through the interlayer channel, an air working medium inlet is formed in the portion, located on the edge of the circular truncated cone structure, of the interlayer channel, the working medium enters the interlayer channel where the working medium flows through the working medium inlet, absorbs low-density solar energy flow on the edge of a light spot so as to be pre-heated after passing through the low-temperature heat absorbing area, absorbs the high-density solar energy flow in the center of the light spot so as to be in the high-temperature state after entering the high-temperature heat absorbing area and finally flows out of the heat absorber through the working medium outlet, and thus light-heat conversion is completed. According to the two-stage heat absorber, the density Gaussian distribution characteristic of the solar energy flow of the light spot is fully considered, the heat absorber is divided into the low-temperature heat absorbing area and the high-temperature heat absorbing area, in this way, radiant heat loss of the heat absorber can be reduced, and the heat efficiency of the heat absorber is improved.

Condensation management techniques for a gas flow delivery system. The techniques include providing a radiant barrier associated with patient circuit and / or a patient interface, providing a water trap and / or an absorbent insert in the patient interface device, or a combination of these techniques. The radiant barrier prevents condensation from forming in the patient circuit and / or the patient interface. The water trap and absorbent insert in the patient interface control condensation that reaches or forms in the interior of the patient interface to prevent it from interfering the user of the gas delivery system.

The invention belongs to the technical field of energy utilization and particularly relates to a compound parabolic condensation type heat collection and dissipation device with the heat collection function at daytime and the radiation refrigeration function at night. The compound parabolic condensation type heat collection and dissipation device comprises a box body with the top surface opened, a compound parabolic condenser, a glass pipe and a support. The interior of the box body is of a compound parabolic shape. The support is arranged around the box body, the compound parabolic condenser is arranged in the box body, and the glass pipe is arranged in the center of the bottom of the compound parabolic condenser. A water inlet and a water outlet are formed in the two ends of the glass pipe respectively and communicated with the outer surface of the box body. The outer surface of the glass pipe is plated with a solar heat collection and radiation refrigeration composite coating. The compound parabolic condensation type heat collection and dissipation device can collect heat at daytime and carry out radiation refrigeration at night, and therefore the problem that traditional compound parabolic condensation type vacuum pipe heat collectors and radiation refrigeration devices are single in function is effectively solved.

The invention discloses a multifunctional low-temperature scroll plate pre-cooling heat exchanger. The multifunctional low-temperature scroll plate pre-cooling heat exchanger includes an intermediateslit structure, a threaded hole, a spiral groove, a U-shaped groove, a fixing hole and a temperature measuring and heating threaded hole. The heat exchanger is applied to a pre-cooling unit of a pre-cooling type JT refrigerator for a liquid helium temperature zone and a room temperature zone. The heat exchanger can not only directly replace a cold head of a pre-cooler, but also can be used as a supporting bottom plate of a cold screen. The intermediate slit structure increases the heat exchange area, so that the pre-cooling efficiency is greatly improved. The spiral groove is in interference fit with a high-pressure pipeline to pre-cool high-pressure and high-temperature helium. The surface of the heat exchanger is plated with a micron-level thin gold layer to reduce radiation leakage heatloss. The U-shaped groove facilitates the arrangement of pipelines and wires, and can further be used as heat sink of the wires from the liquid helium temperature zone to the room temperature zone. The multiple functions of the cold head of the pre-cooler, the support of the cold screen, the pre-cooling of high-pressure fluid and the heat sink of the wires are integrated, the structure is compact, the contact thermal resistance between the pre-cooler and the heat exchanger is reduced, the pre-cooling effect of a refrigerator is enhanced, and the pre-cooling efficiency is improved.

The invention belongs to the technical field of energy utilization and particularly relates to a compound parabolic condensation type heat collection and dissipation device with the heat collection function at daytime and the radiation refrigeration function at night. The compound parabolic condensation type heat collection and dissipation device comprises a box body with the top surface opened, a compound parabolic condenser, a glass pipe and a support. The interior of the box body is of a compound parabolic shape. The support is arranged around the box body, the compound parabolic condenser is arranged in the box body, and the glass pipe is arranged in the center of the bottom of the compound parabolic condenser. A water inlet and a water outlet are formed in the two ends of the glass pipe respectively and communicated with the outer surface of the box body. The outer surface of the glass pipe is plated with a solar heat collection and radiation refrigeration composite coating. The compound parabolic condensation type heat collection and dissipation device can collect heat at daytime and carry out radiation refrigeration at night, and therefore the problem that traditional compound parabolic condensation type vacuum pipe heat collectors and radiation refrigeration devices are single in function is effectively solved.

The invention discloses a solar photo-thermal utilization energy gathering module with a convex lens array, and belongs to the technical field of solar photo-thermal utilization. The system comprises a convex lens array energy gathering structure, the convex lens array energy gathering structure comprises a plurality of convex lenses which are connected in series or in parallel, the convex lenses which are connected in series or in parallel form a matrix structure, and focuses of the convex lenses which are connected in series or in parallel are located on the same plane; and the heat collection plate is located on one side of the convex lens array energy gathering structure, a medium circulation pipeline is arranged on the heat collection plate, a heat absorption medium circulates in the medium circulation pipeline, and the heat collection plate is used for absorbing high-temperature heat energy generated by focusing of the convex lens array energy gathering structure. The photo-thermal utilization rate can be improved, the heat loss is reduced, and meanwhile the manufacturing and using cost is reduced.

The invention discloses a novel solar heat collection pipe with a built-in heat absorber. The novel solar heat collection pipe comprises the heat absorber, a black paint coating, heat transferring media, an inner-layer glass sleeve, an outer-layer glass sleeve, a selective penetration layer and the like. The black paint coating is coated on an outer side surface of the heat absorber; the heat absorber is arranged in the heat transferring media and the heat transferring media are arranged on inner and outer sides of the heat absorber; a narrow air layer is formed between the inner-layer glass sleeve and the outer-layer glass sleeve or a gap between the inner-layer glass sleeve and the outer-layer glass sleeve is vacuumized. The selective penetration layer is designed on the outer surface of the inner-layer glass sleeve and has the characteristics of high transmissivity and low emissivity; the radiation heat loss between the inner-layer glass sleeve and the outer-layer glass sleeve can be effectively reduced. The solar heat collection pipe provided by the invention has the characteristics of high heat collection efficiency, small heat loss, convenience for modularized installation and the like, can applied to devices including a non-focusing type heat collector or a linear focusing type heat collector and the like, and provides technical supports for further large-scale popularization and application of a solar heat collector.

The invention provides a solid waste decoupling combustion device, a solid waste decoupling combustion system device and a combustion method of the solid waste decoupling combustion device. The combustion device comprises a shell, wherein the interior of the shell is divided into a feeding combustion channel, a flue gas mixed combustion channel and a flue gas afterflame channel which are sequentially communicated through partition plates in the material flowing direction, and the feeding combustion channel is divided into a preheating drying area, a pyrolysis gasification area, a semi-coke area and a burnout area in the material flowing direction; an air distribution device is arranged below the feeding end in the feeding combustion channel, and vent holes are formed in the outer wall of the side, close to the preheating drying area and the pyrolysis gasification area, of the air distribution device; at least one deflection baffle is arranged in the flue gas afterflame channel, and a rotary deflection flue gas flow channel is formed in the flue gas afterflame channel through the deflection baffles; and an air-smoke heat exchanger is arranged in the flue gas afterflame channel close to the outlet. Through the reasonable flue and air distribution design and the optimized combustion process, materials are fully combusted, and the combustion device has the advantages of being compact in structure, small in pollutant emission and the like.

A solar concentrating utilization system comprises a plurality of photovoltaic reflecting plates which are arranged in a specific shape and / or arrangement to form a concentrating device, and each photovoltaic reflecting plate is used for absorbing part of sunlight for photovoltaic power generation and reflecting other sunlight which is not absorbed by the photovoltaic reflecting plate or totally reflecting the sunlight; and a concentrating spectrum utilization device which is arranged at or near the focus of the concentrating device formed by the plurality of photovoltaic reflecting plates andis used for utilizing the sunlight reflected by the photovoltaic reflecting plates. According to the system, the solar spectrum suitable for being used by the photovoltaic cell in the solar spectrumis used by the photovoltaic cell, and the sunlight of the residual solar spectrum is gathered to the concentrated spectrum utilization device, so that the full-spectrum utilization of solar energy isrealized. And the energy ratio of photovoltaics to condensation can be adjusted, optimal matching is carried out according to a utilization method, and the overall utilization efficiency of solar energy is improved.

The invention discloses a secondary heating volumetric solar air receiver belonging to the field of solar heat utilization. The secondary heating volumetric solar air receiver is composed of a primary preheating zone, an air flow channel and a secondary heating zone. In the preheating zone, the cavity between the heat-insulating shell, the support plate and the heat-insulating inner plate forms a first-level preheating zone, the cavity between the flow channel heat-insulating shell, the support plate and the inner quartz glass forms an air flow channel, and the heating zone is insulated and The inner cylindrical cavity surrounded by the shell of the support plate forms the secondary heating zone. Foam ceramic materials are installed in the primary preheating zone, air flow channel and secondary heating zone, and the front surface of the receiver is covered with quartz glass outside to form a secondary heating volumetric solar air receiver; by adjusting the air in the high radiation area The sequence of flow through the low-radiation area and the form of secondary heating improve the absorption efficiency of the solar receiver. The invention can be used in parallel or alone; it can improve the absorption efficiency of the solar receiver.

The invention discloses a solar water-working-medium cavity-type heat absorber, and belongs to the technical field of light-condensation solar thermal power generation devices. The heat absorber comprises a gas supplying unit, a heat exchanging unit and a cavity. The gas supplying unit comprises a CO2 gas storage tank connected with the cavity, a gas pump is further arranged on a pipeline connected with the cavity, a first valve is arranged at an exhausting opening of the CO2 gas storage tank, and a second valve is arranged at a gas inlet of the cavity. The heat exchanging unit comprises a heat exchanger connected with the cavity, the heat exchanger is communicated with an exhausting pipeline of the CO2 gas storage tank through a bypass pipeline, and a bypass valve is arranged on the bypass pipeline. An air discharging valve and a CO2 gas discharging valve are arranged at the top of the cavity. Greenhouse gas is sufficiently utilized, a novel utilization mode which saves energy and reduces emissions is adopted, and the heat absorber is reasonable in structural arrangement and easy to obtain and has broad application prospects.

A campfire shield provides a heat-reflective, windproof, insulated, flexible shield that may be positioned around a campfire by means of stakes. In some embodiments, the present invention may provide for a barrier that reflects and retains a campfire's heat while also blocking the wind around the campfire.

The present invention relates to a cathode ray structure for a cathode ray tube, and more particularly, to a cathode structure for a cathode ray tube capable of maximizing thermal efficiency and minimizing power consumption.

The invention discloses a groove type solar heat collecting tube for high temperature. The heat collecting tube comprises a glass outer tube (2) and a metal inner tube (1), wherein the metal inner tube (1) is provided with a high-temperature-resistant selective absorbing coating (3), the glass outer tube (2) coaxially sleeves the metal inner tube (1), and an annular vacuum closed space (4) is formed between the glass outer tube (2) and the metal inner tube (1). The periphery of the inner wall of the glass outer glass tube (2) is divided into two parts of an illuminating surface (5) and a non-illuminating surface (6), the inner wall of the illuminating surface (5) of the glass outer tube (2) is provided with an antireflection film layer, and the antireflection film layer is located on a light-gathering side; and the inner wall of the non-illuminating surface (6) of the glass outer tube (2) is provided with a reflecting layer, and the reflecting layer is positioned on a non-light-gathering side, wherein the reflectivity of the reflecting layer is more than 85% of a silver film layer, a aluminum film layer or a copper film layer.