44results about How to "High limit temperature" patented technology

Disclosed is a novel compound, namely a pentacyclic liquid crystal compound having a CF2O bonding group, which has general physical properties necessary for a compound, stability against heat and light, a wide temperature range of a liquid crystal phase, a high clearing point, good compatibility with other compounds, and large dielectric anisotropy and large refractive anisotropy. This pentacyclic liquid crystal compound has a particularly high clearing point and particularly large refractive anisotropy. Also disclosed are a liquid crystal composition and a liquid crystal display.

The invention relates to a heat-transfer heat-accumulation medium prepared by combining quartz sand and a multi-composition molten nitrate salt and a preparation method, and belongs to the field of solar photo-thermal power generation. The heat-transfer heat-accumulation medium is composed of a multi-composition molten nitrate salt system and quartz sand. The invention also provides the preparation method of the heat-transfer heat-accumulation medium. The heat-transfer heat-accumulation medium disclosed by the invention keeps the low melting point of the multi-composition molten nitrate salt, and also helps to improve the upper limit operating temperature of the multi-composition molten nitrate salt, and the upper limit operating temperature is up to 700 DEG C. The heat-transfer medium is low in cost, wide in operating temperature range, good in heat stability and high in thermal conductivity, and is extremely suitable for a solar thermal power generation system and a heat-accumulation heat-transfer system based on solar photo-thermal power generation.

Disclosed is a liquid crystalline medium which has a wide liquid crystal phase temperature range, a high refractive index anisotropy and high dielectric anisotropy, and has an optically isotropic liquid crystal phase. The liquid crystalline medium comprises a liquid crystalline compound having a pyridine ring and a linking group -CF2O- and a chiral agent, and can exhibit an optically isotropic liquid crystal phase.

Disclosed is a liquid crystal compound having general properties required for a compound; stability against heat, light and the like; a wide liquid crystal phase temperature range; a high clearing; good compatibility with other liquid crystal compounds; and a large refractive index anisotropy and dielectric constant anisotropy. Further disclosed is a liquid crystal composition containing said liquid crystal compound. Further disclosed is a liquid crystal display element containing said liquid crystal composition. The compound is expressed by general formula (1). (1) For example, R1 is an alkyl with 1-20 carbons; at least one of the rings A1-A6 is pyrimidine-2,5-diyl or pyridine-2,5-diyl, with the remainder being 1,4-cyclohexylene or 1,4-phenylene; Z1-Z6 are single bonds; L1-L4 are hydrogen or a halogen; X1 is hydrogen, a halogen, -C=N, or an alkyl with 1-10 carbons; and l, m, n, o, p, and q are 0 or 1, with l+m+n+o+p+q= 3.

A liquid crystal medium, which has a liquid crystal phase over a wide temperature range, a large refractive index anisotropy, and a large dielectric anisotropy, and exhibits an optically isotropic liquid crystal phase, is provided. The liquid crystal medium is characterized by containing a liquid crystal compound having four benzene rings and a difluoromethyleneoxy group, and a chiral reagent, and exhibiting an optically isotropic liquid crystal phase.

Disclosed are a compound which has a large refractive index anisotropy, a large dielectric constant anisotropy, and a low melting point; and a liquid crystal medium which has a wide liquid crystal phase temperature range, a large refractive index anisotropy, a large dielectric constant anisotropy, and an optically isotropic liquid crystal phase. Specifically disclosed are a liquid crystal compound which has a chlorobenzene ring, and a liquid crystal medium which contains the liquid crystal compound and a chiral agent and exhibits an optically isotropic liquid crystal phase.

A polymer containing perspex as its main component features that the content of its syndiotactic structure is 55 mole% and its weight decreasing temp is 290 deg.C or higher for the 5 Wt%. Its advantage is high resistance to thermocracking and high temp.

The invention discloses a solar boiler constant-temperature energy conservation control system capable of conducting composite amplification type temperature detection. The solar boiler constant-temperature energy conservation control system is composed of a boiler, a heater, a first water pump, a first ball valve, an air energy heat pump, a second water pump, a second ball valve, a softened water processor and a solar power generation system. The solar power generation system is composed of a solar cell panel, a protection circuit, a control circuit, a storage battery connected with the control circuit, a switch circuit connected with the storage battery, an adjustable integrated filtering and voltage stabilizing circuit connected between the switch circuit and the storage battery in series, and a composite amplification type temperature detection circuit connected between the adjustable integrated filtering and voltage stabilizing circuit and the switch circuit in series. The solar boiler constant-temperature energy conservation control system is characterized in that a constant-temperature adjustable circuit is connected between the switch circuit and the heater in series. The solar power generation system is adopted in a boiler heat supply system, energy is effectively saved due to the adoption of the solar boiler constant-temperature energy conservation control system, the pollution to the atmosphere is reduced, and real energy conservation and environment protection are achieved.

The invention discloses a high-temperature-resistance carbon aluminum composite pipe in the technical field of carbon aluminum composite pipes. The high-temperature-resistance carbon aluminum composite pipe comprises a carbon aluminum composite pipe body; a high-temperature resisting layer is wrapped on the outer wall of the carbon aluminum composite pipe body; a thermal insulation layer is wrapped on the outer wall of the high-temperature resisting layer; heat conducting columns are uniformly mounted out of the thermal insulation layer; the ends, far from the thermal insulation layer, of theheat conducting columns are connected with cooling layers; condensation pipes, matched with the heat conducting columns, are uniformly mounted in inner cavities of the cooling layers; cooling liquid layers are mounted in inner cavities of the condensation pipes; the condensation pipes are connected through annular liquid guide pipes; liquid filling pipes are mounted at the tops of the annular liquid guide pipes; heat on the thermal insulation layers is transferred into the condensation pipes by the heat conducting columns; cooling liquid in the condensation pipes is used for cooling; the cooling liquid is injected through a liquid charging port; and the cooling liquid flows into three sets of liquid filling pipes through flow separation pipes, and flows into the annular liquid guide pipesto enter the condensation pipes for continuous cooling. The high-temperature-resistance carbon aluminum composite pipe is simple in structure, high in temperature upper limit, and good in cooling effect, and filling of the cooling liquid is convenient.

The invention provides a method and a device for preparing ethylene glycol by hydrogenating dimethyl oxalate. A nickel-based catalyst is adopted to improve the upper limit temperature of a catalyst operation temperature window; meanwhile, multi-stage reaction is adopted, so that the amount of circulating hydrogen can be reduced, and the energy consumption of the circulating compressor is reduced;the device can adopt an adiabatic reactor, so that the equipment cost can be reduced.

The invention belongs to the technical field of air conditioner refrigeration, and particularly relates to a double-evaporation energy-saving air conditioner unit. The double-evaporation energy-savingair conditioner unit comprises an air conditioner unit shell, a fan I, a cooling water curtain and a surface cooler I, wherein the fan I, the cooling water curtain and the surface cooler I are arranged in the air conditioner unit shell, the air conditioner cooling water curtain and the fan I are arranged at an air inlet and an air outlet of the unit shell respectively, a water collecting disc anda water curtain water feeding system are arranged at the bottom of the unit shell, the water curtain water feeding system is used for conveying water in the water collecting disc to the upper part ofthe unit cooling water curtain, and spraying the water to the unit cooling water curtain, so that air passes through the water curtain to be cooled, and then passes through the surface cooler I to becooled. A water inlet of the surface cooler and a water outlet of the surface cooler are connected with a water cooling system through a freezing water conveying pipe and a freezing water return piperespectively. According to the double-evaporation energy-saving air conditioner unit, energy is saved, the efficiency is improved, the temperature range of refrigerating operation environment of theair conditioner equipment can be widened, the maximum limiting temperature is increased, and the air conditioner unit can still work normally in an energy-saving mode under the extreme weather, for example, the ambient temperature rises.