36results about How to "Avoid the Coffee Ring Effect" patented technology

The invention proposes a method for measuring the coverage ratio of ligands on the surface of quantum dots. Determination of the coverage rate K of ligands of organic ligands containing sulfhydryl groups or nitrogen on the surface of quantum dots by potentiometric titration i , which can be used to evaluate the quality of quantum dots. If K i less than 2*10 ‑10 mol / cm 2 , the quality of quantum dots is not good, and K i Increase the value before proceeding with applications such as solution or ink dispensing. Adopt this method to determine quantum dot surface ligand coverage rate, result is accurate, easy to operate, further, can guarantee the stability of quantum dot surface ligand content by the method of the present invention, can guarantee the solubility of different batches of quantum dots, avoid The coffee ring effect caused by the different drying rates when the quantum dot solution is prepared into a film can improve the uniformity of the pixel resolution, turn-on voltage, and photoelectric efficiency of the quantum dot display panel.

Embodiments of the present invention provide a display substrate, a method for fabricating the same, and a display device. The display substrate includes a base substrate on which a pixel defining layer is provided, and a space for accommodating the pixel defining layer is formed between the pixel defining layers. In the pixel area of ​​the pixel ink, a light-to-heat conversion layer for converting light energy into heat energy is arranged on the pixel defining layer to ensure that the pixel ink has a uniform thickness after film formation and avoids coffee ring effect.

The invention provides a method for rapidly detecting bacterial endotoxin based on surface-assisted laser desorption ionization mass spectrometry. The method prepares a zinc ferrite chitosan compositeand takes the zinc ferrite chitosan composite as a matrix, and a method for rapidly detecting the bacterial endotoxin based on an organic mass spectrometry technology is developed to overcome a coffee-ring effect of a traditional organic matrix and facilitate the rapid detection of the bacterial endotoxin. The method has the advantages that no complex sample pretreatment is needed, the sample consumption amount is small (about 0.1muL), the sample preparation is simple, the time consumption is less, the salt tolerance is good, and the reproducibility is good and the like, and has a good application prospect in the fields of food and drug safety.

The invention discloses a chip sintered product, a sub unit, an IGBT packaging module and a preparation method. The chip sintered product comprises a first molybdenum sheet, a second molybdenum sheetand a chip placed between the first and second molybdenum sheets; at least one of the first and second molybdenum sheets is a prefabricated molybdenum sheet; the prefabricated molybdenum sheet is a molybdenum sheet with a prefabricated nanometer silver film on the surface; in addition, at least one surface of the chip is in contact with the prefabricated nanometer silver film; by adoption of the prefabricated nanometer silver film, distribution uniformity of nanometer silver particles in the subsequent pressuring and sintering process can be improved effectively, a "coffee ring effect" can beavoided, and thermal resistance can be lowered; meanwhile, it is ensured that nano-scale holes are uniformly distributed in a sintering layer obtained by sintering, and by virtue of the nano-scale holes, stress generated between the chip and the molybdenum sheet can be lowered effectively, and the shearing strength of the chip sintered product is improved; and by adoption of the chip sintered product and the IGB packaging module with low thermal resistance and high shearing strength, the sintering layer obtained by sintering the prefabricated nanometer silver film has high compactness, and thenano-scale holes are distributed.