45results about How to "Wide phase transition temperature range" patented technology

The invention discloses a preparation method for phase-M vanadium dioxide nanometre powder. The preparation method comprises the following steps: mixing polyhydric alcohol with a carbon chain length of 3 to 10 with monohydric alcohol with a carbon chain length of 1 to 5 in a volume ratio of 1: (6 to 15), so as to obtain a mixed alcohol solution; then adding quaternary ammonium salt with a carbon chain length of 1 to 16 in the mixed alcohol solution, so as to obtain electrolyte, wherein the concentration of quaternary ammonium salt in the electrolyte is 1-5 g / L; then using a vanadium metal block as an anode, using a platinum metal block or a vanadium metal block as a cathode, keeping a distance between the anode and the cathode to be 2 mm to 5 cm, placing the anode and the cathode in the electrolyte, and electrolysing for 1 to 3 hours under a voltage of 2 to 30 V, so as to obtain a reaction solution containing precipitates; then performing a solid-liquid treatment and a washing treatment on the reaction solution, so as to obtain an intermediate product; and after that, annealing the intermediate product for 1 to 3 hours at a temperature of 350 to 450 DEG C and under a pressure of 10 to 100 Pa, so as to prepare the target product with a particle size of 50 to 100 nm. The preparation method has the characteristics of being time-saving, energy-saving, environment-friendly, low in preparation cost, and easy to realize large-scale industrialized production.

The invention provides a composite phase-change thermal storage material. A porous material with high thermal conductivity is used as a supporting framework, and low-melting-point metal or low-melting-point metal with nano-particles is distributed in pores of the porous material, wherein melting point or solidus temperature of the low-melting-point metal is less than or equal to 80 DEG C; and thermal conductivity of the porous material is within 40-400 W / (m.K). The material provided by the invention has high equivalent thermal conductivity and high storage energy density; there is a large contact area between the liquid metal and the porous material; and the material has a wide application temperature range, has good fixability, stable physico-chemical property and good reversibility; and the problem of decreasing heat storage efficiency after multiple times of heat adsorption and release cycles is avoided.

The invention discloses a liquid crystal composition. The liquid crystal composition has a wide phase transition temperature scope, high resistance, high stability, high double refraction anisotropy and rapid response and good high- and low-temperature stability, can still produce fast response at a low temperature of 0-30 DEG C and is especially suitable for industrial control instruments and vehicle-carried TNTFT-LCD. The liquid crystal composition comprises 1-20wt% of a compound I, 1-50wt% of a compound II, 1-30wt% of a compound III, 1-50wt% of a compound IV, 1-20wt% of a compound V and 0.05-0.5wt% of an optical rotation component.