3results about How to "Limit extension" patented technology

This application relates to the field of building materials technology and discloses a low-cost micro-expansion ultra-high performance concrete and its preparation method. The raw materials of the concrete include water, cement, silica fume, limestone powder, fine aggregate, coarse aggregate, polycarboxylate superplasticizer, CaO-calcium sulfoaluminate-based composite expansion agent, and sodium polyacrylate-based internal curing agent. The fine aggregate is river sand, and the coarse aggregate is basalt crushed stone. During preparation, the powders are first mixed dry, then an aqueous solution of the superplasticizer is added and stirred into a uniform slurry. The aggregate is then added, stirred, and finally molded and cured. This invention utilizes the internal curing agent to desorb moisture when the internal humidity of the concrete matrix decreases, providing moisture compensation for the later hydration of the composite expansion agent, causing the dense matrix to undergo micro-expansion deformation and convert it into self-stress. This solution effectively compensates for the volume shrinkage caused by the low water-cement ratio, reducing the risk of cracking. Simultaneously, the use of conventional sand and gravel instead of pure quartz sand significantly reduces the cost of large-scale preparation.

The invention relates to the technical field of solar cells, in particular to a photovoltaic cell assembly and a preparation method thereof.The preparation method comprises the following steps that a cell piece is prepared, specifically, a silicon wafer with the half size serves as a raw material, selective patterning etching is conducted on the front face and the back face of the textured silicon wafer to form two grooves, and the width of the groove in the front face is smaller than that of the groove in the back face; and sequentially plating an amorphous silicon / microcrystalline silicon thin film and a transparent conductive film, removing the transparent conductive film in the groove, and then carrying out subsequent steps and slicing. And assembly manufacturing: the groove processing position is located below the non-groove processing position of the other battery piece during series welding of the battery assembly. The grooves are arranged in the fragmentation areas of the front and back surfaces of the battery piece, so that the phenomenon that the transparent conductive film is not thoroughly removed by etching slurry or laser or the amorphous / microcrystalline layer is damaged can be well avoided.

The application discloses a hydraulic engineering ring geological fracture measuring device capable of being quickly installed, which comprises a supporting frame, an expansion supporting mechanism and an auxiliary traction mechanism arranged on the supporting frame, and a traction shaft penetrating through the expansion supporting mechanism and the auxiliary traction mechanism, one end of the traction shaft is provided with a winding mechanism, and the other end is provided with a sampling measuring mechanism. The servo motor drives the adjusting ring gear to rotate through the driving gear, and the rotating position of the adjusting ring gear is limited through the side wheels, the adjusting ring gear applies the thrust force to the fixed gear, the fixed gear is fixedly connected with the expansion arc plate, the expansion arc plate and the fixed gear can be synchronously rotated, the sliding pin of the expansion arc plate is inserted into the inside of the sliding rail, the sliding pin can be moved on the sliding rail, the movement track of the sliding pin can be limited, the expansion range of the expansion arc plate can be limited, the expansion arc plate can be rotated to a suitable position, and the expansion arc plate can provide support for the device.