Abstract: An information transmission method based on blockchain, which includes the following steps. A sender creates a transmission contract on a blockchain, submits a digest of to-be-transmitted information to the transmission contract, and sends the ciphertext of the to-be-transmitted information, an address of a receiver and an address of the transmission contract to a first transmission node of a transmission network. The first transmission node sends the ciphertext of the to-be-transmitted information, an address of the receiver and an address of the transmission contract to a second transmission node in a point-to-point manner. The second transmission node receives and delivers the ciphertext of the to-be-transmitted information and the address of the transmission contract to the receiver, and generates and submits a receipt acknowledgement to the transmission contract. This application also provides an information transmission system and device, and a computer-readable storage medium.

Abstract: Provided is a preparation method of near-infrared silver sulfide quantum dots. The silver sulfide quantum dots have hydrophilic groups derived from a mercapto-containing hydrophilic reagent attached on the surface thereof, and the hydrophilic reagent is any one of mercaptoacetic acid, mercaptopropionic acid, cysteine, cysteamine, thioctic acid and ammonium mercaptoacetate or any combination thereof. The silver sulfide quantum dots have high fluorescence yield, good fluorescence stability, good biocompatibility and uniform sizes. The preparation method has moderate reaction conditions, simple operation, short production cycle, good reproducibility and is easy to control. The silver sulfide quantum dots can be used in the application of cellular imaging and biological tissue imaging.

Abstract: Provided is a preparation method of near-infrared silver sulfide quantum dots. The silver sulfide quantum dots have hydrophilic groups derived from a mercapto-containing hydrophilic reagent attached on the surface thereof, and the hydrophilic reagent is any one of mercaptoacetic acid, mercaptopropionic acid, cysteine, cysteamine, thioctic acid and ammonium mercaptoacetate or any combination thereof. The silver sulfide quantum dots have high fluorescence yield, good fluorescence stability, good biocompatibility and uniform sizes. The preparation method has moderate reaction conditions, simple operation, short production cycle, good reproducibility and is easy to control. The silver sulfide quantum dots can be used in the application of cellular imaging and biological tissue imaging.

Abstract: Provided are near-infrared silver sulfide quantum dots, a preparation method thereof and a biological application thereof. The silver sulfide quantum dots have hydrophilic groups derived from a mercapto-containing hydrophilic reagent attached on the surface thereof, and the hydrophilic reagent is any one of mercaptoacetic acid, mercaptopropionic acid, cysteine, cysteamine, thioctic acid and ammonium mercaptoacetate or any combination thereof. The silver sulfide quantum dots have high fluorescence yield, good fluorescence stability, good biocompatibility and uniform sizes. The preparation method has moderate reaction conditions, simple operation, short production cycle, good reproducibility and is easy to control. The silver sulfide quantum dots can be used in the application of cellular imaging and biological tissue imaging.