Study on Administrative and Educational Measures of China Urban Public Fire Safety Education

AbstractTo provide basis of scientific research for administrative and educational measures of China urban public fire safety education in and to ensure its effective implementation, the present situation and problems of China urban public fire safety education are investigated. Based on the research on forming process of public fire safety quality, the requirements of public fire safety education and the efficient education measures are studied. The present management and implement system and its problems of China urban public fire safety education are analyzed, based on a developed information system of public fire safety education and management, a suggested administrative system, enforcement mechanism and implement scheme of public fire safety education measures are proposed in this paper to provide guidance in reforming administrative and educational measures of China urban public fire safety education so as to change the situation of “activities of fire safety education years after years resulting in no improvement of fire safety quality of the public” and make true contribution to improving public fire safety quality in China

DeepACO: Neural-enhanced Ant Systems for Combinatorial Optimization

Ant Colony Optimization (ACO) is a meta-heuristic algorithm that has been successfully applied to various Combinatorial Optimization Problems (COPs). Traditionally, customizing ACO for a specific problem requires the expert design of knowledge-driven heuristics. In this paper, we propose DeepACO, a generic framework that leverages deep reinforcement learning to automate heuristic designs. DeepACO serves to strengthen the heuristic measures of existing ACO algorithms and dispense with laborious manual design in future ACO applications. As a neural-enhanced meta-heuristic, DeepACO consistently outperforms its ACO counterparts on eight COPs using a single neural model and a single set of hyperparameters. As a Neural Combinatorial Optimization method, DeepACO performs better than or on par with problem-specific methods on canonical routing problems. Our code is publicly available at https://github.com/henry-yeh/DeepACO.Comment: Accepted at NeurIPS 202

Acoustic Droplet Ejection Enabled Automated Reaction Scouting

Miniaturization and acceleration of synthetic chemistry are critically important for rapid property optimization in pharmaceutical, agrochemical, and materials research and development. However, in most laboratories organic synthesis is still performed on a slow, sequential, and material-consuming scale and not validated for multiple substrate combinations. Herein, we introduce fast and touchless acoustic droplet ejection (ADE) technology into small-molecule chemistry to transfer building blocks by nL droplets and to scout a newly designed isoquinoline synthesis. With each compound in a discrete well, 384 random derivatives were synthesized in an automated fashion, and their quality was monitored by SFC-MS and TLC-UV-MS analysis. We exemplify a pipeline of fast and efficient nmol scouting to mmol- and mol-scale synthesis for the discovery of a useful novel reaction with great scope

Stability and electronic properties of sulfur terminated two-dimensional early transition metal carbides and nitrides (MXene)

Experimental results have shown that two-dimensional early transition metal carbides such as Nb2C also can be terminated by S atoms. In this study, 20 types of sulfur terminated MXenes (M2XS2, where M = Sc, Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, and W; X = C, N) are investigated using the density functional theory method. Phonon frequency analysis and molecule dynamic simulations upon 1000 K results show that V2CS2, Cr2NS2, Nb2CS2, Hf2CS2, and Ta2CS2 are dynamically stable. Formation enthalpy calculations indicate that two-dimensional V2CS2, Nb2CS2, Ta2CS2, Hf2CS2, and Cr2NS2 structures have the highest stability and may be easily synthesized. It indicates that MXenes can also be terminated by S atoms, which is influenced by the synthesis process. The binding energies for V2CS2, Nb2CS2, and Cr2NS2 bilayer systems are smaller than 0.18 eV/atom, which indicates they can be easily separated into single layers. In contrast, the binding energies for Ta2CS2 and Hf2CS2 bilayers systems are up to 0.326 and 0.36 eV/atom, respectively. This indicates that Ta2CS2 and Hf2CS2 are relatively difficult to separate into single layers, which can be attributed to the localized p-orbitals of S atoms. Ta2CS2 is a direct band gap semiconductor with band gap of 0.36 eV. Cr2NS2 system is ferromagnetic material among MXenes, with the average magnetic moment of Cr atoms of 1.60 mu(B). This research provides new viewpoints for the synthesis and surface termination of MXenes

Improving the Dyeing Properties of Peanut Skin Extracts to Flax Fabrics by Chitosan Pretreatment

Using chitosan as pretreatment agent, the dyeing properties of peanut skin extracts (PSE) to flax fabrics were improved. Flax fabrics have excellent comfort property and are loved by many people. However, flax is different to dye, especially with natural dye. In this research, chitosan was used to pretreat flax fabrics and PSE was used to dye the pretreated flax fabric. The optimal conditions of the chitosan pretreatment and dyeing conditions of PSE were investigated according to the K/S value of the dyed flax fabrics. Comparing the original flax fabric, the chitosan pretreated flax fabric significantly improved the absorption to PSE, and the dyed fabrics had an increased K/S value from 0.9 to 3.9, and had good color fastnesses. The main chemical constitution in PSE such as catechin, chitosan, and cellulose of flax fabrics may form hydrogen bond and ionic bond. Chitosan pretreated and dyed flax fabrics had a stronger ability to UV resistance and scavenging free radicals. The fluorescence intensity of the dyed flax fabrics was improved while it was decreased after chitosan pretreatment. Chitosan pretreatment combined PSE dyeing can be used to develop functional flax textiles without using metallic mordants