Abstract: A liquid crystal writing screen, including: first substrate and second substrates, and a bistable liquid crystal layer between the first and second substrates, where the first substrate includes: a first base substrate; a plurality of pixel units on a side of the first base substrate proximate to the second substrate, each pixel unit including a thin film transistor, and a pixel electrode electrically connected to a first electrode of the thin film transistor; a passivation layer on a side of the thin film transistor distal from the first base substrate and in contact with the thin film transistor; where the pixel electrode is between the first base substrate and the passivation layer; and a spacer on a side of the passivation layer distal from the first base substrate and in contact with the passivation layer. A method for preparing the liquid crystal writing screen is further provided.

Abstract: Disclosed are a display substrate, a display panel and a display device. The display substrate includes: a base substrate, multiple gate-line groups, multiple data lines, the multiple data line include: first type of data lines and second type of data lines alternately arranged along the first direction; multiple transistors, transistors in the same sub-transistor group are connected with the same gate line, transistors in adjacent sub-transistor groups are connected with different gate lines, and transistors of the same sub-transistor group are connected with different data lines; multiple pins, the multiple pins include: first type of pins and second type of pins alternately arranged along the first direction; two adjacent first type of data lines are connected with a same first type of pin, and adjacent second type of data lines are connected with a same second type of pin.

Abstract: The present disclosure provides an ultra-high temperature resistant cement slurry system for cementing and the preparation method and use thereof. The cement slurry system comprises cement, an ultra-high temperature strength stabilizer, an ultra-high temperature reinforcing material, a density regulator, an ultra-high temperature suspension stabilizer, a dispersant, a fluid loss additive, a retarder, a defoaming agent and water, wherein the ultra-high temperature suspension stabilizer comprises an ether-based starch, an aluminosilicate and a polyalcohol polymer. The method for preparing the cement slurry system includes dry mixing and wet mixing raw materials homogeneously, respectively, and then homogeneously mixing the dry mix and wet mix to obtain the cement slurry system. The present disclosure further provides use of the cement slurry system for cementing in deep wells and ultra-deep wells at high and ultra-high temperatures.

Abstract: A well cementing method is described for improving cementing quality by controlling the hydration heat of cement slurry. By controlling the degree and/or rate of hydration heat release from cement slurry, the method improves the hydration heat release during formation of cement with curing of cement slurry, improves the binding quality between the cement and the interfaces, and in turn improves the cementing quality at the open hole section and/or the overlap section. The cementing method improves cementing quality of oil and gas wells and reduces the risk of annular pressure.

Abstract: A high-strength Portland cement slurry for ultra-high-temperature cementing, a preparation method therefor and an application thereof. In parts by weight, the composition of the cement slurry comprises: 100 parts of Portland cement, 4-6 parts of a high temperature anti-cracking material, 80-105 parts of a high-temperature reinforcing material, 70-78 parts of water, 0.5-1.5 parts of a dispersant, 1-3 parts of a fluid loss reducer, 0.5-2.5 parts of a retarder and 0.2-0.5 parts of a defoamer; the high-temperature reinforcing material is a combination of acid-washed quartz sand, metakaolin and aluminum sulfate, a combination of acid-washed quartz sand, metakaolin, feldspar and sodium sulfate, or a combination of acid-washed quartz sand, metakaolin, feldspar and calcium nitrite. The cement slurry has good settling stability, rapid strength development in low temperatures, high compressive strength of cement stone at a high temperature of 600° C.

Abstract: The invention provides a high temperature resistant Portland cement slurry and a production method thereof. The high temperature resistant Portland cement slurry comprises the following components by weight: 100 parts of an oil well Portland cement, 60-85 parts of a high temperature reinforcing material, 68-80 parts of fresh water, 1-200 parts of a density adjuster, 0.1-1.5 parts of a suspension stabilizer, 0.8-1.5 parts of a dispersant, 3-4 parts of a fluid loss agent, 0-3 parts of a retarder and 0.2-0.8 part of a defoamer. The high temperature resistant Portland cement slurry has a good sedimentation stability at normal temperature, and develops strength rapidly at a low temperature. The compressive strength is up to 40 MPa or more at a high temperature of 350° C., and the long-term high-temperature compressive strength develops stably without degradation.

Abstract: A well cementing method is described for improving cementing quality by controlling the hydration heat of cement slurry. By controlling the degree and/or rate of hydration heat release from cement slurry, the method improves the hydration heat release during formation of cement with curing of cement slurry, improves the binding quality between the cement and the interfaces, and in turn improves the cementing quality at the open hole section and/or the overlap section. The cementing method improves cementing quality of oil and gas wells and reduces the risk of annular pressure.

Abstract: The invention provides a high temperature resistant Portland cement slurry and a production method thereof. The high temperature resistant Portland cement slurry comprises the following components by weight: 100 parts of an oil well Portland cement, 60-85 parts of a high temperature reinforcing material, 68-80 parts of fresh water, 1-200 parts of a density adjuster, 0.1-1.5 parts of a suspension stabilizer, 0.8-1.5 parts of a dispersant, 3-4 parts of a fluid loss agent, 0-3 parts of a retarder and 0.2-0.8 part of a defoamer. The high temperature resistant Portland cement slurry has a good sedimentation stability at normal temperature, and develops strength rapidly at a low temperature. The compressive strength is up to 40 MPa or more at a high temperature of 350° C., and the long-term high-temperature compressive strength develops stably without degradation.