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Estrogen combined with physical barrier therapy may be a prospective method to repair a damaged endometrium and prevent postsurgical re-adhesion in the treatment of intrauterine adhesions (IUAs), but there lacks a suitable scaffold with good biocompatibility, appropriate mechanical properties, and drug-releasing kinetics. Herein, a mechanically robust and stable barrier based on the poly(hydroxyethyl methacrylate) (PHEMA) hydrogel combined with estradiol-loaded mesoporous silica is designed. The network is formed by covalent bonds and noncovalent coordination bonds, which endow the hydrogel with superior mechanical properties to most reported PHEMA-based hydrogels. Meanwhile, the covalent bonds impart excellent stability to the hydrogel, which maintains its structure and mechanical properties in a simulated uterine fluid for 30 days. The excellent mechanical properties and stability are comparable to those of a typical barrier material intrauterine device (IUD), enabling the hydrogel to be retained in the uterus and removed intact like an IUD.

A novel N-doped carbon dots (N-CDs (CA + BU)) derived from citric acid (CA) and benzoylurea (BU) were prepared by a green, simple and environment friendly synthetic method free of solvents. The N-CDs (CA + BU) is found to be served as highly selectivity PL sensor for Fe(III) detection. Systematic investigation showed that only Fe(III) can quench the PL of N-CDs (CA + BU) among the test metal ions. The N-CDs (CA + BU) could serve as a sensitive “turn-off” fluorescent sensor for Fe(III) and the detection limit was as low as 1.1 μM. In addition, the mechanism of Fe(III) quenching to the PL of N-CDs (CA + BU) was thoroughly studied. The absorption spectrum of N-CDs (CA + BU) with or without Fe(III), the influence of temperature on PL quenching and the PL lifetime were studied and discussed. The results confirmed that the quenching belongs to dynamic quenching. Finally, PL imaging and intracellular Fe(III) sensing were realized in A549 cells.

The rapid development of plug-in hybrid electric vehicles and renewable generation brings new challenges to the secure and economic operation of power systems. A reactive power optimization model based minimizing network loss is established, considering electric vehicle stochastic charging /discharging and uncertain outputs of wind turbines. To improve the accuracy and global searching capability, The modified membrane computing (MMC) based communication rule, cross transposition rule and mutation rewrite rule is proposed. Finally, the modified IEEE-33 nodes system is simulated through the proposed algorithm and general GA. The effectiveness and correctness of the proposed method and model are verified.

A pulse combustor employed in a spray-drying system offers a new approach for liquid atomization that yields high-quality powders at low cost. Using a pulse combustion atomizer, there is no need for any form of nozzle dispersion and its atomization mechanism differs from those of conventional atomizers, such as rotary atomizers and pressure and pneumatic nozzles. In this work, based on the analysis of atomization mechanism, experiments of unsteady pulsating atomization were carried out in an experimental system of a Helmholtz-type pulse combustor. An optical analyzer was used for measuring the mean diameter of atomized droplet and droplet distribution. The effects of liquid feed rate, air flow oscillatory frequency, and liquid viscosity on atomized droplet size and size distribution were investigated and analyzed. The results indicate that the uniform droplet size distribution can be obtained under the conditions of a low feed rate, high-frequency pulsating flow, and moderate viscosity. The range of the d...