With the rapid development of information technology,the development of blockchain technology has also been deeply impacted.When performing block verification in the blockchain network,if all transactions are verified on the chain,this will cause the accumulation of data on the chain,resulting in data storage problems.At the same time,the security of data is also challenged,which will put enormous pressure on the block,resulting in extremely low communication efficiency of the block.The traditional blockchain system uses theMerkle Tree method to store data.While verifying the integrity and correctness of the data,the amount of proof is large,and it is impossible to verify the data in batches.A large amount of data proof will greatly impact the verification efficiency,which will cause end-to-end communication delays and seriously affect the blockchain system’s stability,efficiency,and security.In order to solve this problem,this paper proposes to replace the Merkle tree with polynomial commitments,which take advantage of the properties of polynomials to reduce the proof size and communication consumption.By realizing the ingenious use of aggregated proof and smart contracts,the verification efficiency of blocks is improved,and the pressure of node communication is reduced.
Jin WangWeiOuWenhai WangRSimon SherrattYongjun RenXiaofeng Yu
Hydraulic fracturing is one of the most important techniques for enhancing oil/gas production.The permeability-based hydraulic fracture(PHF)model,which is based on the smeared-crack method and considers the interaction between the pore pressure and solid phase,is adopted in the present study for a fully-coupled simulation of the hydraulic fracture in a heterogeneous rock formation.The level set method(LSM),which is used to describe the distribution of material properties of heterogeneous rocks,is coupled with the PHF model.Using the coupled PHF–LSM model,a series of finite element method(FEM)simulations are carried out to investigate the characteristics of a hydraulic fracture(e.g.,the breakdown pressure and fracture propagation)in heterogeneous rocks.Three types of heterogeneous rocks are examined:layered rock,rock with distributed inclusions,and rock with random spatial variations in the material properties.The results of the numerical simulations show that the coupled PHF–LSM model can describe the material interface without changing the FEM mesh used to discretize the physical domain.Further,the model effectively simulates hydraulic-fracturing problems for various heterogeneous rocks.
Ming LiPeijun GuoDieter F.E.StolleLi LiangYitao Shi
During past few years,the construction of fluorescent metallacycles featuring the fluorescenceresonance energy transfer behavior has attracted extensive attention due to their diverse applications such as real-time monitoring the dynamics of coordination-driven self-assembly,photoswitching fluorescence-resonance energy transfer,and light-controlled generation of singlet oxygen for cancer therapy.This review focuses on the recent advances on the design principles,preparation methods,optical properties,and the wide applications of fluorescent metallacycles with the FRET property.
