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To explore the influence characteristics of the interaction effects between meteorological factors on ozone(O

Until now, the selective (hetero)aryl C–H alkylation without the assistance of directing groups or preinstallation of functionalities still remains a highly challenging goal. Herein, by developing acid-resistant multispherical cavity carbon-supported cobalt oxide nanocatalysts (CoOx/MSCC) and a hydrogen transfer-mediated activation mode for nonactivated N-heteroaromatics, we present a direct reductive quinolyl and isoquinolyl β-C–H alkylation with various aldehydes as the alkylating agents. The catalytic transformation features broad substrate scope, good functional tolerance, use of Earth-abundant and reusable cobalt catalysts, and no need for prefunctionalizations, demonstrating that the developed nanocatalysts enable one to directly functionalize inert N-heteroaryl systems that are difficult to realize by organometallic complexes.

This paper reported the fabrication of high-performance ZnIn2S4 photocatalysts using ionic liquid microemulsion-mediated hydrothermal method under facile conditions. The influences of reaction temperature and aging time on the catalytic properties of the specimens were investigated. The crystal phase, optical property, and morphological structure of the obtained catalysts were characterized using X-ray diffraction, UV–visible spectrometer, electronic microscope, and N2 adsorption–desorption techniques. The results indicated that all of the ZnIn2S4 samples prepared by this method consisted of the hexagonal phase and exhibited excellent photoresponse capability and photocatalytic performance. The sample prepared at 60 °C with an aging time of 6 h showed the best photocatalytic performance, and the corresponding degradation rate of methyl orange was measured as 98.5% after 10 min. The current study highlights an efficient and environmental method for the formulation of high-performance ZnIn2S4.

Grid division is the geometric expression forms and vectors of CFD numerical simulation engineering problems. The quality of the grid has an important impact on the CFD accuracy and computational efficiency about CFD. In this paper, it compares the structured and non-structured grid process summary base on blade pump. During a large number of mechanical fluid grid division and performance calculations, and combining with the theoretical guidance based on rotating machinery fluid Dynamics calculations, it summarizes some experience and practice on blades grid division optimization.

This paper formulates a radial basis function meshless method for the numerical simulation of the advection-diffusion problems. The spatial derivatives are approximated by RBF collocation technique whereas the temporal derivatives are discretized using the Crank-Nicholson method. Corresponding boundary conditions are enforced analytically at a discrete set of boundary nodes. The performances of the present method are demonstrated through their application to an advection-diffusion problem.

The mixed materials come from Beijing Daxing District, corn stalks as the main raw material, peanut shells and wheat straw as affixation. Combustion characteristics of mixed materials are studied by using Thermogravimetric analyzer and combustion dynamics studied by using Coats-Refern method to offer practical and theoretical data for crop straw combustion and Densified . Studies have shown that Combustion curve of three samples have two distinct peaks, divided into water evaporated to dryness, and the combustion of volatiles, fixed carbon combustion and burnout four basic stages and lied a larger overlapping area in the entire combustion stage, That combustion characteristics and kinetic parameters of mixed materials are influenced by adding peanut shells, and less affected on adding wheat straws.

Based on a lot of tests, domestic based oil and additives were chosen according to the working characteristics of heavy duty and supercharged diesel in this paper. The nyctinasty of compound additive produced by American EXXON company and domestic CD-package to based oil was inspected respectively by tests[1]. Dealing with the datum of orthogonal test by computer, the three optimum formulates of 20w/40 heavy duty and supercharged diesel oil were presented.

This paper analyzes the basic combustion characteristics of dual-fuel engine with diesel-natural gas, including the engine’s running characteristics, the external characteristics and the low-load performance. Taking the development and application of natural gas for consideration, this paper also makes studies on how to improve the dynamic performance of the dual-fuel engine CA6110ZLA5N2.

This paper makes road test on two kinds of engine lubricant, one contains nano-ceramic additives, and one does not. Results show that the lubricant containing nano-ceramic additives can fully meet the requirements of automotive engine, and nano-ceramic lubricant is superior in anti-wear properties to other lubricant in experiment, and nano-ceramic additives can improve the anti-wear properties of lubricant.

To investigate the preventive effect of exogenous nucleotide (EN) on the developmental toxicity of alcohol.C57BL/6J pregnant mice were divided into 6 groups randomly: the control group, the alcohol group, the low (0.01%EN), middle (0.04%EN), high (0.16%EN) and higher (0.64% EN) intervention groups. From the 6th gestational days (GD) to the 15th GD, pregnant animals except those in the control group were administrated with 5 g (per kg body weight) alcohol intragastrically. Normal mouse forage was provided to the animals in the control group and alcohol group, while forage containing different quantities of EN was provided to the animals in the intervention groups. On GD 18, all the dams were killed, their blood samples were collected for further analysis, and fetal developmental indexes were observed.Compared with the animals in the alcohol group, offspring's body weight and placenta weight of EN intervention groups improved a lot; superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activity increased significantly (P0.05), malondialdehyde (MDA) levels decreased significantly (P0.01); the live birth rate of animals in the interventions groups has increased significantly and the absorbed embryo rate of them has decreased significantly (P0.01); the forepaw phalanges, hindpaw phalanges and caudal vertebrae ossification point increased significantly (P0.01); the anomalies of both occipital and sternum have decreased significantly in 0.04%EN group (P0.05).EN has a significant protective effect on the developmental toxicity of alcohol.