44results about How to "Reduce devitrification" patented technology

The present invention provides one kind of low expansion coefficient micro crystalline glass comprising SiO2 51.5-64 wt%, P2O5 6.8-11 wt%, Li2O 3-5.2 wt%, MgO 0.5-2.2 wt%, ZnO 0.4-2.1 wt%, CaO 0.2-2.5 wt%, BaO 0.5-4.5 wt%, SrO 0.2-3 wt%, and Sb2O3 0.6-2 wt%, Al2O3+SiO2 75-84 wt%, and TiO2+ZrO2 3.5-5 wt%. The micro crystalline glass has expansion coefficient at 20-100 deg.C of + / -0.6x10<-7> / K, visible light transmittance up to 90 %, low recrystallization trend and easy formation.

The invention discloses a preparation method of a high-imido and high-methoxylation melamine resin capable of being cured at low temperature. According to the method, the high-imido and high-methoxylation melamine resin capable of being cured at low temperature is obtained by reacting melamine, a formaldehyde solution and methanol, paraformaldehyde is not required to be added, the step of synthesis of hydroxymethylation melamine as an intermediate product is omitted, preparation costs are reduced, links of crystallization, drying and the like of the intermediate product are omitted, energy consumption is low, a technological process is simple, the methanol only needs to be added at one step in reaction, and the preparation method is easy to control. In addition, a mixture of hydrochloric acid and formic acid is used as an etherification catalyst, and the effect of the obtained product is better than that of a single acid catalyst.

A manufacturing method of a high-pressure mercury lamp includes an electric field application step in which an electric field is applied to at least a light emission part (4) with the high-pressure mercury lamp being kept at a high temperature. This can reduce impurities such as hydrogen and alkali metals in a discharge space (8) and glass forming the light emission part (4). As a consequence, blackening and devitrification of the high-pressure mercury lamp while the lamp is lit can be reduced.

The invention discloses a glass microballoon manufacturing device comprising a furnace body (1) and a waste gas treatment device, wherein the furnace body (1) is formed by air-tight connection of an upper part and a lower part, the upper part of the furnace body is of a cubic shape, a waste gas emission port (4) is arranged at the top of the upper part, one or more injection-type burners (2) are horizontally installed on the side of the upper part, a preheating air pipe (14) is arranged in the upper part, the lower part of the furnace body is of a square conical shape, and one or more microballoon collectors (3) are arranged at the bottom of the lower part. According to the glass microballoon manufacturing device and the preparation method thereof provided by the invention, the furnace body which adopts the cubic structure enlarges the cooling space; the horizontally installed injection-type burners and the preheating air pipe arranged in the furnace body can give full play to the heat value of fuel, thus reducing energy source waste, saving energy and reducing emission; TiO2 and Al2O3 with relatively lower costs are adopted, the refractive index of the product is greater than or equal to 1.93; and the glass microballoon manufacturing device and the preparation method thereof have the advantages of reducing devitrification, improving the cooling velocity, having good product quality, improving the utilization ratio of raw material, being capable of large-scale production, and the like.

The invention provides improved near infrared ray filter glass which comprises a glass substrate with the thickness of 0.19 mm-0.4 mm. The center wavelength of the glass substrate is in a range of 640 nm-650 nm; the glass substrate comprises, by the molar percentage, 35%-45% of Al(PO3)3, 10%-25% of P2O5, 3%-7% of SrO and 6%-15% of CuO. The improved near infrared ray filter glass has excellent chemical stability and high penetration rate, has the molding temperature reduced, and can be resistant to severe high temperature and high humidity environments.

A high-pressure discharge lamp has a pressure chamber with two opposite end regions and delimited by a cylindrical envelope made of glass. An electrode is provided at each of the two end regions, the electrodes projecting into the pressure chamber and being arranged in the pressure chamber as anode and cathode. A discharge chamber is formed between the electrodes. The two end regions of the pressure chamber are designed differently at least outside of the discharge chamber.