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The rapid increase in the concentration of CO₂ raises global concern. The latest research indicates that the concentration has reached a new peak of 400^[1] ppm. Effective CO₂ abatement strategies, such as Carbon Capture and Storage (CCS), are of great interest. One common method of CCS is MEA absorption. This paper aims to illustrate post-combustion capture with MEA solvent. The principles, procedures, influencing factors, advantages and drawbacks are discussed to better understand what hinders existing power plants from retrofitting with this technology.

The microstructures of the Mg-6Zn-2Y alloy solidified under high pressures were investigated using scanning electronic microscopy (SEM) and X-ray diffraction (XRD). The room-temperature compression behavior was analyzed through experiments, showing that the microstructures of the alloys are consisted of α-Mg and quasicrystal I-Mg3Zn6Y phases. With solidification pressure increasing, the microstructures were refined, and the morphologies of the inter-dendritic secondary phase were improved from continuous networks into long-island and granule. The compression strength, yielding strength and compressibility were increased significantly corresponding with solidification pressure, from 259.02 MPa, 230.39 MPa and 18.3% under ambient pressure to 361.43 MPa, 272.25 MPa and 33.1% under high pressure of 6 GPa. The cleavage planes are flat, and the cleavage steps are straight under ambient pressure. However, the cleavage planes are small and rough under 4-6 GPa; tearing dimples occur in the tearing area, indicating that the degree of cleavage fracture decreases under high pressure.

Polyurethane prepolymer capped by vinyl group (PUV) was synthesized by reaction of hydroxyethyl methacrylate and toluene diisocyanate using di-n-butyltin dilaurate as catalyst, and then polyurethane-poly(butyl acrylate) hybrid latexes were prepared via miniemulsion polymerization of PUV and butyl acrylate (BA). Fourier transform infrared, differential scanning calorimeter were adapted to characterize the structure of PUV and PU-PBA and the properties of their films. The results show that the decrease of BA/PUV ratio result in an increase of the hardness and glass transition (T_g) of PU-PBA, but reduce the stability of miniemulsion and elasticity of final copolymer films.

Single-grain grinding test plays an important part in studying the high speed grinding mechanism of materials. In this paper, a new experimental system for high speed grinding test with single diamond grain is presented. The differences of surface topography and chip morphology of Inconel 718 machined by single diamond grain and single CBN grain were evaluated. The grinding forces and corresponding maximum undeformed chip thickness were measured under different grinding speeds. The chips, characterized by crack and segment band feature like the cutting segmented chips, were collected to study the high speed grinding mechanism of nickel-based superalloy. The results show that the grinding speed has an important effect on the forces and chip formation, partly due to the temperature variation. As the speed increases, the groove surface becomes smoother.

The EG scheme also had some shortcomings: the node could not resist attack effectively, and only one routing path was used during the communication. To solve these problems, this scheme proposed to use the multi-path routing to replace the one routing, and the pairwise key was established after the hash function. The connectivity of the system was improved by the multi-path routing, if one routing path was broken, there were also some other alternative paths. Due to the hash function, the attackers could not get any useful information. So the proposed scheme can not only develop the connectivity of the WSNs, but also improve the security of the system.

When Shape memory alloy (SMA) wires are embedded in the composite structure with a specific volume fraction, the properties of the resulting hybrid composite structure, which is called SMA-reinforced composite structure, will be reinforced. Some of SMA wires embedded in the composite can be viewed as two electrodes of the capacitor. The deformation of the composite structure will cause change of the capacitor, therefore the segmental SMA wires embedded in the composite may be considered as the self-sensitive element of structure strain monitoring. The measurement circuit monitoring the change of micro capacitor in structure is designed, and it is integrated with radio frequency identification (RFID) technology to compose RFID sensor-tag, and the variation of capacitor is send to the RFID reader wirelessly to form a wireless health monitoring system. Experimental results show that this RFID sensor-tag and its system can be feasibly used in wireless structural health monitoring of SMA-reinforced composite structure.

The nickel^II complex [Ni (C₉H₉O₃)₂(H₂O)₂], Diaqua-bis (ethylvanillinato-O,O')-nickel^II, the Ni^II atom is located on a twofold axis and is coordinated by two ethylvanillinate anions and two water molecule in a distorted octahedral geometry . The ethylvanillinate ligand chelates to the Ni^II atom through its ethyl and hydroxy O atoms,with greatly differing Ni-O bond distances (2.282(2) Å and 1.9792(16)Å). Adjacent complex link to each other via hydrogen bonds forming the three-dimensional supramolecular structure.

For increasing the experimental efficiency and shortening the experimental time, the uniform design method was used to establish the wear experiment scheme on the tribological properties of the sealing material CrMo cast iron. The experiments were investigated on a vertical universal friction and wear tester, the worn surfaces of specimens were observed by scanning electron microscope (SEM). The results showed that the experiment points chosen by the uniform design is reasonable and effective, and the wear rate distribution rule of the CrMo cast iron was established and was divided three regions, the effect on wear rate in the I region and the III region was more serious than the II region, and the variation of the friction coefficient is bigger under experimental conditions, the main wear mechanism of the CrMo cast iron is desquamation wear and adhesive wear. The load and sliding speed coupling effect on wear of the CrMo cast iron must be thought over.

With the extensive use of composite materials in aviation industry, the research of factors which affect their basic performances in production and usage has become very important. In this paper, a finite element analysis model is built by the commercial software MSC.Nastran / Patran to research the effect of fiber lay-up direction misalignment on the natural frequency of composite laminates. The results show that, in the same boundary conditions, stacking sequence has a significant impact on the natural frequencies and vibration modes of composite laminates, and in the lay-up process, the natural frequency change of laminates caused by 0° fiber lay-up direction misalignment is much larger than the natural frequency change of laminates due to 90° fiber lay-up direction misalignment. In the process control and certification of composite laminate plates lay-up, special attention should be taken to the inspection of 0° direction fibers.

Ha Tai high speed rail is a high-speed railway in cold region of China. The design criteria is very strict. There is many frozen soil over cold region. The research how to reduce the amount of subgrade frost heaving over Ha Tai high speed rail is of great significance.We use a frost heave model to simulate the subgrade frost heaving in the paper.We research how the fine power content and water content influence the frost heave amount of graded crushed stone by contrast test.The result shows that the fine power content and the water content have great influence on the frost heave amount of graded crushed stone .The frost heave ratio increases with the fine powder content and the water content.