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Domain knowledge graph has become a research focus in the era of artificial intelligence. Radio transmission equipment type approval is the core function of radio equipment management. This paper introduces construction process of the radio transmission equipment type approval knowledge graph, and analyses algorithms of the knowledge graph by category, which is a great tool for knowledge mining. The question answering construction over the knowledge graph is also discussed as an application, which has laid the foundation for further research in radio regulatory knowledge graph.

A passive air sampler was used to monitor the concentration and contamination profile of 18 polychlorinated biphenyls (PCBs) in the atmosphere over the urban and industrial area of Gaolan, a city in northwest China, during the non-heating and heating seasons of 2018, and the sources, pollutant transport, and the health risks of PCB exposure were analyzed and assessed using principle component analysis, trajectory modeling, and inhalation exposure modeling. The atmospheric concentration in the study area ranged from 110.2 to 429.9 pg·m

Polymer-dispersed liquid crystal (PDLC) and polymer-stabilized liquid crystal (PSLC) are two typical liquid crystal (LC)/polymer composites. PDLCs are usually prepared by dispersing LC droplets in a polymer matrix, while PSLC is a system in which the alignment of LC molecules is stabilized by interactions between the polymer network and the LC molecules. In this study, a new material system is promoted to construct a coexistence system of PDLC and PSLC, namely PD&SChLC. In this new material system, a liquid-crystalline vinyl-ether monomer (LVM) was introduced to a mixture containing cholesteric liquid crystal (ChLC) and isotropic acrylate monomer (IAM). Based on the different reaction rates between LVM and IAM, the PD&SChLC architecture was built using a stepwise UV-initiated polymerization. During the preparation of the PDS&ChLC films, first, the mixture was irradiated with UV light for a short period of time to induce the free radical polymerization of IAMs, forming a phase-separated microstructure, PDLC. Subsequently, an electric filed was applied to the sample for long enough to induce the cationic polymerization of LVMs, forming the homeotropically-aligned polymer fibers within the ChLC domains, which are similar to those in a PSLC. Based on this stepwise UV-initiated radical/cationic polymerization, a PD&SChLC film with the advantages of a relatively low driving voltage, a fast response time, and a large-area processability is successful prepared. The film can be widely used in flexible displays, smart windows, and other optical devices.

We have designed a solar thermoelectric cogenerator (STECG), which can supply electric power and heat simultaneously, by adding thermoelectric modules to the heat pipe in evacuated tubular solar collectors. A pilot experiment shows that the STECG can generate 0.19 kW h of electrical energy and about 3001 of hot water at 55 degrees C in 1 day when the figure of merit of the thermoelectric module, ZT(M), is 0.59 and solar insolation is less than 1000 W/m(2). A theoretical model for accurately predicting the thermal losses, collector efficiency and electrical efficiency of the STECG is also presented based on energy balance and heat transfer equations. For thermoelectric modules with ZT(M) = 1, when the solar insolation, wind velocity, ambient temperature and water temperature are 1000 W/m(2), 1.3 m/s, 25 degrees C and 25 degrees C, respectively, the collector efficiency, output electrical power and electrical efficiency are calculated to be 47.54%, 64.80 W and 1.59%, respectively. The results show that STECGs combining heat pipes with thermoelectric modules in evacuated tubular solar water heaters are economical and practical, making them suitable for commercial production. (c) 2013 Elsevier Ltd. All rights reserved.

In order to find antiviral compounds with novel structures, geldanamycin and lamivudine with different antiviral mechanisms were conjunctively synthesized to acquire a new compound TC-GM, and the antiviral activity of TC-GM was measured. The antiviral activity against HIV-1 was examined by p24 antigen ELISA kit. The activity against HBV was examined by dotblot. The activity against HSV and CoxB virus was examined by CPE. TC-GM exhibited broad-spectrum antiviral activities similarly like geldanamycin. TC-GM inhibited the replication of different viruses, including HIV-1, HBV, HSV 1 and 2, CoxB6. TC-GM showed more potent inhibitory activity against HIV-1 and HBV than other detected virus.