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Uniform temperature distribution within solid catalyst particles is important to achieving low coke formation in a high-temperature reaction. However, the issue of uneven temperature distribution exists in most fixed-bed catalytic reaction systems. Here, we developed a microwave-assisted system and used it in catalytic dehydration of glycerol for sustainable production of acrolein. A coated microwave absorbing catalyst WO3/ZrO2@SiC was prepared and employed in the catalytic reactions. The effects of reaction temperature, ZrO2/SiC ratio, and weight hourly space velocity (WHSV) on glycerol conversion and arcolein selectivity were examined. Experimental results showed that the microwave heating proved to be more effective than the conventional electric heating for glycerol dehydration to acrolein at lower temperature. The acrolein selectivity reached over 70% with complete glycerol conversion at 250 oC by microwave heating. The catalyst acidity was greatly influenced by ZrO2/SiC ratio, which in turn determined the acrolein selectivity. More importantly, much better catalyst stability was obtained in the microwave-heating process than the electric-heating process. In addition, the microwave-heating system was effective for the in-situ regeneration of deactivated catalyst.

A closer integration of machine learning and relational databases has gained steam in recent years due to the fact that the training data to many ML tasks is the results of a relational query (most often, a join-select query). In a federated setting, this poses an additional challenge, that the tables are held by different parties as their private data, and the parties would like to train the model without having to use a trusted third party. Existing work has only considered the case where the training data is stored in a flat table that has been vertically partitioned, which corresponds to a simple PK-PK join. In this paper, we describe secure protocols to compute the join results of multiple tables conforming to a general foreign-key acyclic schema, and how to feed the results in secret-shared form to a secure ML toolbox. Furthermore, existing secure ML systems reveal the PKs in the join results. We strengthen the privacy protection to higher levels and achieve zero information leakage beyond the trained model. If the model itself is considered sensitive, we show how differential privacy can be incorporated into our framework to also prevent the model from breaching individuals' privacy.

4 figures, 1 table. Biomass-derived nanocarbons (BNCs) have attracted significant research interests due to their promising economic and environmental benefits. Following their extensive uses in physical and chemical research domains, BNCs are now growing in biological applications. However, their practical biological applications are still in their infancy, requiring critical evaluations and strategic directions, which are provided in this review. The carbonization of biomass sources and major types of BNCs are introduced, encompassing carbon nanodots, nanofibres, nanotubes, and graphenes. Next, essential biological uses of BNCs, antibacterial/antibiofilm materials (nanofibres and nanodots) and bioimaging agents (predominantly nanodots), are summarized. Furthermore, the future potential of BNCs, for designing wound dressing/healing materials, water and air disinfection platforms, and microbial electrochemical systems, is discussed. We reach the conclusion that a crucial challenge is the structural control of BNCs. Furthermore, a key knowledge gap for realizing practical biological applications is the lack of systematic comparisons of BNCs with nanocarbons of synthetic origin in the current literature. Although we did not attempt to perform an exhaustive literature survey, the evaluation of the existing results indicates that BNCs are promising as easily accessible materials for various biomedically and environmentally relevant applications. Y. C. acknowledges financial support from the Australian Research Council under the Future Fellowships scheme (FT160100107) and a Tianjin city-sponsored short-term visiting project.

Single walled carbon nanotubes (SWNTs) are potential candidate of channel material instead of silicon in field effect transistors due to their small diameter, high carrier density and flexibility. Two major obstacles in application of SWNT networks in field effect transistors (FETs) are the existence of metallic SWNTs and contact resistance between tubes. To solve these problems, the stripping of SWNT networks and partial alignment of SWNTs has been developed for increasing on/off ratio and mobility of the FETs. This thesis focuses on the design and fabrication of a series of micron pattern to break the metallic percolation pathway and a new partial alignment method to reduce the tube-tube contact resistance in SWNT networks. We fabricate FETs on SiO2/Si wafers with channel width (W) of 20 µm and 50µm, varying channel lengths (L) of 2 − 50 µm and strip width (W') of 2 − 10 µm.). On the SiO2/Si wafer, when on/off ratio of the FETs is > 104, mobility of the best FETs with stripped SWNTs is 3.7±1.25 cm2/V-s. Furthermore, a partially aligned semiconductive SWNT thin film was deposited on silicon dioxide wafers using a novel parallel solution-based immersion-cum-shake method. Superior FET devices with on/off ratio of ~3.2×104 and mobility of 46.5 cm2/V-s are achieved. They are easy and effective ways to reduce both the short coming of metallic SWNTs and the tube-tube resistance in the networks between the source and drain electrodes. DOCTOR OF PHILOSOPHY (SCBE)

We present our study on the mechanical and electronic properties of two-dimensional phthalocyanines (2D-Pc) under external strain using first principles and pz-orbital tight-binding model calculations. The Poisson's ratio and in-plane stiffness calculated in the harmonic elastic strain range are found to be 0.43 and 73.41 J m−2, indicating that 2D-Pc is much softer than graphene. The 2D-Pc can bear the same critical uniform strain as pristine graphene, which reduces the hopping integrals of π-electrons and narrows the width of the bands near the Fermi level. Consequently, the band gap and effective masses of carriers undergo ascending trends as the strain increases. The present study provides meaningful insight into the strain induced variation of electronic transport performance in 2D-Pc and other 2D tetrapyrrole macrocyles.

The E-government of our country has improved a lot since it immerged, but there still existing many problems because of various reasons. In this paper, the author analyzed the personal information service based on multi-Agent of the E-government. This paper introduced the design thought of the system and then gave a model based on the multi-Agent.