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The migration behaviors of Fe adatom on Fe nanoparticles have been explored by the nudged elastic band (NEB) method. We take nanoparticle consisting of 2465 atoms as an example to illustrate the energy barriers and the migration pathways of Fe adatom on Fe nanoparticle. For the adatom at the three typical kinds of locations, the hopping mechanism is more favorable with the lowest barriers and the exchange mechanism requires relatively higher energies. For the single adatom far away from the interface region, a single adatom on each nanoparticle facet follows a migration behavior similar to that on a bcc surface. In the interface region, there is a competition between the direct crossing mechanism and the indirect crossing mechanism. In addition, the locations have obvious influences on the migration behaviors of the adatom and the effects are to some extent restricted by the migration mechanism.

The diffusion behaviors of Fe adatom on Fe nanoparticles with three different sizes have been explored by molecular dynamics (MD) simulation. The activation energies and pre-exponential factors are extracted from the Arrhenius relation. The MD simulation shows that the hopping, exchange and direct/indirect crossing mechanisms contribute to the diffusion of Fe adatom on Fe nanoparticles and the diffusion behaviors do not show a significant nanosize effect.

The sequential microhydration of sodium glycinate is investigated at the MP2/6-311++G(d,p) level. Our results clearly indicate that the microhydration process is driven by the charge site of sodium cation and a bridge site is losing its dominant position. Eventually, a comparison of theoretical and experimental Raman spectra provides the evidence of the predicted structural information.

In modern society, as mechanization and automation of people's work increasing and the widespread of transportation instead of walking, a sedentary lifestyle which lacks of exercise become one of the ten major reasons causing global death, frequent disease and disability. Negative impact bringing people "Modern Urban Civilization Syndrome" represented as cardiovascular and cerebrovascular diseases has expanded extensively and rapidly, which has made people's health continue to deteriorate. To this end, more and more people become concern about health, and hope to improve their physical conditions through indoor and outdoor fitness. However, the public has generally ignored an "invisible killer" - effects of air pollution on health during fitness. This paper regards environmental studies and human hygiene as the theoretical basis, studies mainly focusing on impact of indoor and outdoor air pollution on public fitness, and proposes constructive suggestions on this basis.

Vibration signal carries dynamic information of rotating machinery and the useful information often is corrupted by noise. Effective signal de-noising and feature extraction methods are necessary to analyze these signals. In this paper, an improved lifting scheme is proposed for such vibration signal analysis. The auto-correlation factor of scale decomposition vibration signal is used as to optimize the prediction operator and update operator at each sample point, which can adapt to the vibration signal characteristic. Improved lifting scheme decomposition and reconstruction procedures are designed. Experimental results confirm the advantage of the proposed method over redundant wavelet transform for rolling bearing fault diagnosis, and the typical fault features in time domain are desirably extracted by improved lifting scheme.

As a new way of storing energy, magnetic suspension flywheel energy storage, has provided an effective way in solving present energy problems with the characteristics of large energy storage, high efficiency and fast charge-discharge speed and so on. The paper mainly elaborated the basic principle of magnetic suspension energy storage system, introduced the structural features of flywheel rotor, magnetic bearing, electric machine, electric power system and other auxiliary body. On this basis, it analyzed applications on electrical peak-modulating, Uninterruptible Power Supply, Hybrid Electric Vehicle, satellite attitude control and so on, on the purpose of the further development and promotion of this new technology.

Magnetic bearing is a high-performance mechatronic bearing, which can suspend parts in space stably using magnetic force. Its characteristics such as high speed, high precision, and low power consumption and so on make it valuable to research and widely to apply in the future. The paper summarized the working principle of magnetic bearing and its characteristics, research and application status. Based on these, it introduced the new application such as used for vibration reduction, dynamic absorber and in mining electromechanical device in engineering field, so as to increase efficiency and save more energy.

The magnetic copolymer was prepared by polymerization of glycidyl methacrylate (GMA) and divinylbenzene (DVB) in the presence of OA-modified magnetic nano-particles. The magnetic strong-base anion exchange resin (MAER) was formed by quaternization of magnetic copolymer. Transmission electron microscope (TEM) and scanning electron microscope (SEM) were used for observation of prepared magnetic nano-particle and MAER, respectively. FT-IR spectrometer was used to characterize the magnetic nano-particle and MAER. To explore the potential application of MAER for natural organic matter (NOM) removal, completely-mixed (CMC) mode was used for humic acid (HA) adsorption. It was found that the HA removal for CMC mode with MAER resin was 10~20% higher than conventional process before breakthrough.

Described is a solid-phase microextraction-gas chromatography mass spectrometric procedure for the determination of galaxolide (HHCB) in water solution samples. In which 100 μm PDMS coated fiber were used. From the optimization experiments of SPME, we found the direct sampling is necessary. The extraction time and temperature were 40min and 35°C, respectively. the salinity of the solution almost has no effect on the extraction efficiency and pH=7.0 was suitable for the extraction of HHCB. The method were applied to the urban sewage and river water respectively and found the content of HHCB in the urban sewage is 286ng/L, while those in river water below limit of quantification.