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First of all,stress analysis of lug under different loading angles was carried out. For the fatigue life analysis of lug under tension-compression loads,the compression load was treated equivalently,and the effective equivalent load factor λ was obtained. The fatigue load spectrum was equivalent to Pmax λPmin,and then the fatigue life of lug structure was obtained by the Detail Fatigue Rating（ DFR） method. Finally,the method was proved by the fatigue test of lug in 45° angles load,which proves that the method is practical in engineering.

International conventions and initiatives can promote collective action against global crises, and strengthen the efforts of countries to take concerted actions. This study summarizes the important international agendas related to marine ecological conservation and restoration, and analyzes China's policy mechanism in recent years. It believes that the policies in China and international documents are synergistic and effective in jointly strengthening efforts to respond to the global crisis. This study also puts forward some countermeasures and suggestions for China to build a detailed regional marine ecological map, strengthen ecological corridor restoration, improve scientific and technological support systems, and promote international cooperation in marine ecological conservation and restoration. [ABSTRACT FROM AUTHOR]

Aiming to solve the complicated problem about the coupling effect of aerodynamic force and heat for hypersonic vehicle, one-way coupling was applied to decouple the environmental load. Then, the distribution of aerodynamic force and heat of a typical composite wing under the flight situation of Mach 5 to Mach 8 was studied by finite element analysis. Based on the classical flutter theory, the critical flutter boundary was obtained. The results show that flutter phenomenon is caused by first-order bending-torsional coupling. Considering the fabricability of the composite wing, the aerothermoelastic tailoring design of composite wing under typical flight situation was carried out. In the optimal process, static intensity and thermal flutter velocity are considered as the constraints, and the optimization target is to obtain minimum mass. For approaching the best structural dynamic characteristics and aeroelastic effect, the bending-torsional coupled stiffness of the composite structure is regulated through changing layers, paving angles and laying sequence. Based on C/C ++ open source environment, a software called Aero-Opt was developed to construct an independent-industrialized analysis platform, and the aerothermoelastic tailoring research of the composite wing under most severe aerodynamic heating condition was carried out. After optimization, the thermal flutter boundary of the composite wing is improved by 22.4%, while its mass is reduced by 15.76% . [ABSTRACT FROM AUTHOR]

A strain of aerobic denitrifying bacteria was isolated and purified from the activated sludge and numbered AHP123, identified as Acinetobacter sp. by 16S rDNA sequencing analysis. The strain could effectively remove NH4+-N and NO3--N, showing well heterotrophic nitrification and aerobic denitrification ability. The results of single factor condition optimization showed that under the conditions of C/N 20, sodium succinate as carbon source, rotation speed 200 r/min, temperature 30 °C, inoculation rate 2% and NH4+-N as single nitrogen source, the NH4+-N removal efficiency achieved 99.26% in 24 h and the removal rate was 4.86 mg/(L½h). Under the conditions of C/N 20, sodium citrate as carbon source, rotation speed 120 r /min, temperature 25 °C, inoculation rate of 2% and NO3--N as single nitrogen source, the NO3--N removal efficiency achieved 92.68% in 24 h and the removal rate was 6.11 mg/(L·h). When NH4+-N and NO3--N were used as mixed nitrogen sources, the removal efficiencies of NH4+- N and NO3--N reached 98.64% and 80.38%, respectively. Furthermore, strain AHP123 showed good application effect in the treatment of anaerobic digestion piggery effluent (ADPE) containing nitrogen. After 48 h of treatment, the removal efficiency of NH4+-N in ADPE reached 99.19%. [ABSTRACT FROM AUTHOR]

Aiming at the problem of large deformation of the roadway caused by the remaining coal pillar in goaf of the extremely close seam, the theoretical and mechanical analysis of the roof failure characteristics and mechanism of the mining roadway in the working face 3101 of Xinwang coal mine were studied. A combined support scheme of anchor-net cable, anchor injection and pressure relief was proposed to analyze the mechanism of the scheme. The anchor-net cable and anchor-injection support solved the problem of large roof deformation, and the pressure-relieving material alleviated the influence of the large deformation of the roadway. FLAC3D numerical simulation was used to analyze the vertical displacement changes of the roadway roof and the distribution of the surrounding plastic zone under the original support scheme and the new combined support scheme. When the combined support scheme of anchor-net cable, anchor injection and pressure relief was adopted, the vertical displacement of the roadway roof was reduced from 569 mm to 143 mm, which was reduced by nearly 75%, and the distribution of the plastic zone was also reduced by 50%. Combined with engineering practice, it has been proved that the new combined support scheme can effectively solve the large deformation of the lower roadway in the goaf of Xinwang coal mine, and provides a theoretical basis for the surrounding rock stability of the roadway in the extremely close coal seam. [ABSTRACT FROM AUTHOR]

The surface molecular imprinting technique is to polymerize and establish the molecular recognition site on the outer layer or surface of the carrier. As a result, the surface molecularly imprinted polymers have the advantages of fast binding speed, strong identification selectivity, high binding capacity and improved efficiency of imprinted materials. In this paper, the principle of surface molecularly imprinted polymers and four preparation methods (sol-gel method, graft copolymerization method, sacrificial carrier method, polymerization plus membrane method, active controllable free radical polymerization) were briefly introduced. Four aspects of drug separation and analysis (traditional Chinese medicine extraction and separation; drug sensors; chiral drug resolution; the application) in drug release was reviewed. [ABSTRACT FROM AUTHOR]

This paper reviews catalytic the hydrotreatment upgrading technology of biomass-derived oil. It provides an overview of the reaction mechanism and the condition of the operation, then summarizes the process of bio-oil hydrogenation at home and abroad. Detailed comparison of various technological processes such as multi-stage hydrogenation, hydrogenation-esterification, in-situ hydrogenation, etc. are made. Multi-stage hydrogenation, which separates the hydroprocessing into two stages (mild hydrotreating and deep hydrotreating), can improve the selectivity of products, moreover avoiding an economic penalty by using less hydrogen. Hydrogenation-esterification combines hydrogenation and esterfication to establish a new upgrading method. Through the method, unstable compounds of biomass-derived oil can be converted more effectively. In-situ hydrogenation, which leads to reducing the cost and enhancing the safety, uses other reagents as resources of hydrogen, simultaneously generating hydrogen and hydrotreating in one reaction system to replace transporting hydrogen from outside. The reasonable optimization of the process routes benefits improving product quality. Research in this area is expected to become a main research direction for bio-oil hydrotreatment. Experimental data were collected about various model compounds including cresol, phenol, guaiacol, acetone, aldehyde, etc. and bio-oil from the literature in the field of this study. Also, a test is reviewed about a range of catalysts including the conventional and novel types of supported noble metal and transition metal catalytic materials and their performance in bio-oil hydroprocessing. Conventional catalysts, such as NiMo and CoMo, have economic advantages; the reaction using noble metal catalysts have better reactivity; amorphous catalysts have both advantages of these two types of catalysts, but amorphous catalysts have terrible thermal stability, and can only be used below 473 K; then, zeolite catalysts and mesoporous catalysts exhibit magnificent effects on reducing oxygen content and moisture content in bio-oil, but still can't avoid coking in the reaction. Unfortunately, researchers have not found any catalyst's hydrothermal stability good enough to improve the effect of reaction continuously (more than seven days), Deactivation and coking of catalysts are still main problems. Obviously, further study is required to prepare these catalysts which have better durability. Finally, this article gives information about the problems which researchers may meet, including equipment plugging, catalyst deactivation, and high operation costs etc., and predicts that the future research directions of this technology is to optimize the hydrogenation process, and to develop new types of composite catalysts which exhibit excellent activity at low temperature and anti-coking performance. The technology development is still on the way but can play a significant role in supplying increasingly expensive petroleum. [ABSTRACT FROM AUTHOR]