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Four cobalt corrole complexes bearing 0–3 cyano groups on the para-position of the three meso-phenyl rings of the macrocycle were synthesized, characterized and applied for electrocatalytic H2 production in both organic solvent and neutral aqueous media.

The push-pull electronic and steric effect of copper porphyrin catalysts on the cross-dehydrogenative coupling (CDC) reaction between the hydroxyl group of phenol substrates and C(sp3)-H bond have been investigated. Results showed that copper porphyrin bearing electron-withdrawing, bulky steric hindrance or heteroatom of pyridyl groups could increase the catalytic activity in the reaction. 5,10,15,20-(tetrakis(4-pyridyl)porphyrin)copper (CuTPyP) was found the best among all tested catalysts. Phenol substrates bearing various functional groups afforded moderate to excellent yields (99%). Significantly, as compared to other tested copper porphyrins, CuTPyP not only exhibited remarkable higher activity but also could shorten the reaction time from 12 to 6 h.

Do maternal homocysteine (Hcy) concentrations, MTHFR and MTRR genes have effects on the occurrence of fetal aneuploidy?A total of 619 aneuploidy mothers and 192 control mothers were recruited in this study. Differences in distributions of maternal MTHFR 677CT, MTHFR 1298AC and MTRR 66AG genetic polymorphisms and maternal Hcy concentrations between aneuploidy mothers and control mothers were analysed.The maternal MTHFR 677CT polymorphism was found to be a risk factor for the occurrence of many fetal non-mosaic aneuploidies studied here, including trisomies 13, 15, 16, 18, 21, 22, TRA and TS. The maternal MTHFR 1298AC polymorphism was found to be a risk factor specifically associated with the occurrence of fetal trisomy 15 and fetal TS. The maternal MTRR 66AG polymorphism was found to be a risk factor only specifically associated with the occurrence of fetal trisomy 21. The Hcy concentrations of mothers of trisomies 22, 21, 18, 16, 15 and TS fetuses were significantly higher than the Hcy concentrations of control mothers.Overall, data suggested an association between these maternal polymorphisms and the susceptibility of fetal non-mosaic trisomy and Turner syndrome. However, these three maternal polymorphisms had different associations with the susceptibility of different fetal aneuploidies, and the elevated maternal Hcy concentration appeared to be a likely risk factor for fetal Turner syndrome and fetal trisomies.

This paper proposes a new algorithm for abnormal behavior detection in surveillance video. Firstly, the motion information image of each frame is constructed by calculating the optical flow size and the angle difference between the optical flow vectors between consecutive frames, and then the obtained motion image information is input into the convolutional neural network (CNN) for training, and used for video abnormal behavior detection. In the algorithm, the motion information image generated based on optical flow information can provide the motion information features in the video image more accurately, which makes it easier to distinguish the normal behavior and abnormal behavior of the video. The experiment of this algorithm is carried out on the commonly used data set PETS 2009. Experimental results show that the proposed method and other algorithms have a significant improvement in the accuracy of abnormal behavior detection.

In this paper, a novel improved ant colony algorithm is proposed to study the multi-robot task allocation problem. By introducing a backhaul optimization factor, a new task point selection method is designed. The pheromone update method uses a combination of local pheromone update and global pheromone update. At the same time, an improved strategy for re-optimizing the optimal path is designed. Simulation experiments show that the proposed algorithm can further improve the quality and efficiency of the ant colony algorithm.

Ultrasound was applied for the extraction of pectin from chaenomeles. The content of pectin was evaluated by carbazole colorimetric method. Based on the results of the single factor experiment and the orthogonal tests, the optimum extraction parameters are as follows: the solid-to-liquid ratio is 1:4 g/mL, the ultrasonic power is 320 W, the ultrasonic-assisted extraction temperature is 60 °C, the ultrasonic-assisted extraction time is 50 min, and pH value is 2.0. Compared with acid hydrolyze methods, the extraction time of the present technique decreases from 70 min to 50 min, and the extraction yield increases from 1.39% to 2.61%. The results show that ultrasonic-assisted extraction is time-saving and highly efficient, so it provides a new way to extract pectin from chaenomeles.

The cable grading perforating technology is a segmental perforation technology used in oil and gas wells, particularly suitable for the perforation development of shale gas horizontal wells. The cable grading perforating technology takes use of multi-level gun string structure, perforating in the three-core cable conveying way, connected the ground monitoring instrumentation, perforating gun and graded perforation initiation control device by cables, to achieve the purpose of grading perforation. This technology has practically applied in Daqing Oilfield, after several times onsite tests, obtained the success of application of the cable grading perforating technology.

The article is based on the survey of rare earth enterprises in Baotou region, Inner Mongolia, analyzes the sorts of rare earth-containing waste produced in rare earth production and their environmental impact. The main sorts of rare earth-containing waste include: low-grade ore generated in the mining sector, tailings from mineral concentrating; water-soaked residue generated in smelting and separating sectors, and solid waste from functional material producing sectors. The low-grade ore has a certain degree of radioactivity, if the economic and technological conditions allowed it also can be used to produce rare-earth. Tailings from mineral concentrating, in addition to radioactivity, it also produces environment pollution to atmosphere, soil and water. However, these tailings are not waste, but the second rare earth mine. Water-soaked residue is radioactive hazardous waste, now stored in line with disposal regulations. Solid wastes from functional materials producing have been recycled and have less impact on the environment.

In order to settle such a problem that the multi-sensors data fusion results are not good due to data confliction in the coal-rock interface recognition, the paper first carries out the fusion with D-S evidence theory. The fusion results are not correct when there are high-conflicting in the evidence, so a distance function is introduced and weight fusion correction algorithm is put forward. Through test simulation, fusion results respectively with D-S evidence theory, weight correction algorithm and fuzzy neural network are analyzed. The results show: the good results are achieved in the multi-sensor data conflict of coal-rock recognition through weight fusion correction algorithm, and influence of signal conflict is avoided effectively.

Rapid and parallel protein micro/nano array formation provides a powerful tool for protein chip fabrication and protein preservation. This paper presents the characterization of the surface tension and viscosity effects on the formation of nano-liter droplet arrays by a novel instant micro stamper, which can simultaneously immobilize hundreds of proteins on a chip. Capillary force is the major driving mechanism of the micro stamper, flowing protein solutions through the chip channel for array-registration and droplet-size control. Three important properties have been characterized in this paper, including uniformity of the parallel printing process, surface wettability and solution viscosity effect on micro droplet size and the dynamic sequence of micro droplet formation. Experimental results demonstrated the uniformity of the parallel stamping process for protein micro arrays from area to area and chip to chip. The effects of surface wettability of bioassay chips and solution viscosity on droplet-size variation have been investigated in detail by experiments and simulations. Both simulation and experimental results demonstrate that the spot size increases with increasing surface wettability and decreasing solution viscosity, and they showed similar tends. The dynamic process of droplet formation has also been observed and analyzed by high-speed images, demonstrating that the footprint reduction rate, formation time and necking of the printed micro droplet are lower on the more hydrophobic surface. This is due to the rapid shrinkage of the droplet footprint area on a hydrophobic surface, resulting in smaller droplet formation. The droplet size can shrink up to 50% when the contact angle of the bioassay chip surface increases from 30° to 80°. On the other hand, the variation of solution viscosity from 1.02 to 10.08 cp makes the droplet size shrink to 70%.

Robot coalition problem is a complicated combinatorial optimization problem. In this paper, a novel quantum ant colony algorithm for the problem is proposed, where the thought of quantum evolution algorithm is combined with ant colony algorithm. In this algorithm, the pheromone is encoded by quantum bits and a new pheromone representation is designed. To avoid the algorithm falling into local optimum, the strategy of quantum crossover is designed to improve the information structure of population. Simulation results show that the algorithm is more effective than quantum genetic algorithm and basic ant colony algorithm.