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Identity-based proxy re-encryption (IB-PRE) can convert the ciphertext encrypted under Alice’s identity to Bob’s ciphertext of the same message by a semi-trusted proxy with the proper transformation key. The main purpose of our work is to enhance the security of IB-PRE. For outside attacks, all existing IB-PRE constructions from lattices have only achieved a limited or weak security model called IND-sID-CPA security. Therefore, by embedding re-encryption key generation and re-encryption algorithms appropriately in Agrawal et al.’s identity-based encryption scheme from lattices, we construct an IND-ID-CPA secure IB-PRE scheme over decisional learning with errors (LWE) under the standard model. For inside attacks, we propose a new primitive IB-VPRE by extending the basic IB-PRE scheme with a new functionality called re-encryption verifiability, meaning that a re-encrypted ciphertext receiver or a third party can verify whether the received ciphertext is correctly transformed from an original ciphertext or not, and thus can detect illegal activities of the proxy. We realize re-encryption verifiability using the homomorphic signature technique as a black box, making the resulting scheme non-interactive and quantum-immune after instanced by a lattice-based homomorphic signature scheme.

The jet-flow high shear mixer (JF-HSM) is a new type of intensified equipment with special configurations of the rotor and the stator. The mass transfer property and power consumption were studied in the solid-liquid system for a series of JF-HSMs involving different configuration parameters, such as rotor diameter, rotor blade inclination, rotor blade bending direction, stator diameter, and stator bottom opening diameter. The flow characteristics were examined by computational fluid dynamic simulations. Results indicate that the turbulent power consumption of the JF-HSM is affected by the change in rotor blade inclination and stator bottom opening. With the increase in the shear head size and the change in the rotor into a backward-curved blade, the solid-liquid mass transfer rate can be remarkably increased under the same input power. Dimensionless correlations for the mass transfer coefficient and power consumption were obtained to guide the scale-up design and selection of such a new type of equipment to intensify the overall mixing efficiency.

A pore-array intensified tube-in-tube microchannel (PA-TMC), which is characterized by high throughput and low pressure drop, was developed as a gas–liquid contactor. The sulfite oxidation method was used to determine the oxygen efficiency (φ) and volumetric mass transfer coefficient (kLa) of PA-TMC, and the mass transfer amount per unit energy (e) was calculated by using the pressure drop. The effects of structural and operating parameters were investigated systematically, and the two-phase flow behavior was monitored by using a charge-coupled device imaging system. The results indicated that the gas absorption efficiency and mass transfer performance of the PA-TMC were improved with increasing pore number, flow rate, and number of helical coil turns and decreasing pore size, row number, annular size, annular length, and surface tension. The φ, e and kLa of PA-TMC could reach 31.3%, 1.73 × 10−4 mol/J, and 7.0 s−1, respectively. The Sherwood number was correlated with the investigated parameters to guide the design of PA-TMC in gas absorption and mass transfer processes.

The existing reversible data hiding methods in encrypted domain separate image encryption from information embedding and do not make full use of the redundant space in the process of image encryption. In order to improve the performance of reversible data hiding by using the technical characteristics of image encryption, a reversible data hiding method based on McEliece error correction is proposed. Firstly, the segmentation position of bit plane is determined according to the embedding requirement and texture characteristic, and the image is divided into high and low significant bits. Secondly, because of the error-correcting characteristic of McEliece encryption, reversible data embedding can be realized while encrypting low significant bits. Then, the high significant bits are compressed to reserve space for the ciphertext extension of the low significant bits. Finally, the whole high significant bits information is stream-encrypted. As long as the image receiver has the decryption key, the image can be restored without distortion. By concealing the relationship between error correction and secret information mapping, the concealment of secret information transmission can be realized. In addition, due to different processing for different pixels, it can be efficiently transmitted with low computational complexity for applications that only need general images. The simulation results show that this scheme can not only realize the separable operation of information extraction and image recovery but also resist the noise attack to a certain extent. The maximum embedding rates of 10 standard images from USC-SIPI and 50 standard images from BOSS-BASE are 2.228 and 2.323 bpp, respectively.

A novel pore-array intensified tube-in-tube microchannel (PA) with high throughput was developed to couple with a high-shear mixer (PAHSM) for improving its mixing performance. Effects of structural and operating parameters were intensively investigated with the Villermaux/Dushman system. The results indicated that the mixing performance in PAHSM was significantly impacted by the structural parameters, and it increased with both the rotor speed and flow rate but not with the flow ratio. The micromixing time estimated with the incorporation model could reach 10–4 s. Compared with other mixing devices, the PA liquid distributor can significantly enhance the mixing performance of HSM with high throughput but low pressure drop. An artificial neural network (ANN) was applied to correlate the micromixing time with the investigated parameters, and the comparison between the model and experimental data indicated that it was an efficient method to fit experimental data in the PAHSM.

A new kind of pore-array intensified tube-in-tube microchannel reactor (PA-TMCR) was constructed and studied to achieve intensive micromixing performance as well as high throughput but low pressure drop. The Villermaux–Dushman reaction was employed to investigate the micromixing performance with different geometric structures and flow conditions. A Finite-rate/Modified eddy dissipation model (FR/MEDM) was improved with a correlated mixing rate A at the range of Re = 485–5308 to build the mixing model. Both results indicated that the pore size and annular size played a significant role in enhancing the micromixing level, and the design of PA-TMCR should avoid the overlap of flow fields from the adjacent pores and too much pressure-drop in the annular. The micromixing time was estimated with incorporation model and a new energy efficiency was proposed to estimate the lower limit of the reactor efficiency, which would have promising applications to provide guidance on the design of the reactor for the single phase reaction process. The optimal micromixing time could reach 10−4 s in PA-TMCR. The comparison with other reactors shows that the PA-TMCR is an efficient and high throughput reactor to meet the industrial applications with excellent micromixing performance and energy efficiency.

It is promising to design a novel structured micromixer that can be easily processed but also exhibit high mixing efficiency as well as low pressure drop at a wide range of Reynolds numbers. The overbridged structure was introduced into the planner E-shape micromixers for the first time to construct a novel kind of bridge-street structure micromixer, in order to improve the mixing efficiency in the wide range of Reynolds number. We investigated numerically the mixing performance of six overbridged E-shape split-and-recombine micromixers via solving 3D Navier–Stokes equations and adopting species transfer model. It is indicated that at lower Reynolds number the tilted interface in the overbridged channel increases the interfacial area and improves the mass transfer efficiency, while at higher Reynolds number the overbridged channels tend to induce vortices and promote the convective diffusion. The results show that the optimal overbridged micromixer DBEM-3 has excellent mixing efficiency exceeding 95% in the range of Re = 0.5–100. The optimal structure of overbridged micromixer was studied further with different viscosity ratio and power law fluid. In addition, the pressure drop under various Reynolds number was calculated, and the pressure drop of the power law fluid was represented by Euler number to reflect the magnitude of the momentum loss rate. It is illustrated that DBEM-3 has excellent mixing efficiency in wide Reynolds number for three different fluid systems, which has promising applications in the biochemistry analysis or mixing systems.