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Nitrogen-doped graphene (N-rGO) was synthesized in the process of preparation of reduced graphene oxide from the expanded graphite through the improved Hummers’ method. The morphology, structure and composition of nitrogen-doped graphene oxide (GO) and N-rGO were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The nitrogen content of N-rGO was approximately 5 at.%. The electrochemical performances of N-rGO as anode materials for lithium-ion batteries were evaluated in coin-type cells versus metallic lithium. Results showed that the obtained N-rGO exhibited a higher reversible specific capacity of 519 mAh g-1 at a current density of 100 mA⋅g-1 and 207.5 mAh⋅g-1 at a current density of 2000 mA⋅g-1. The excellent cycling stability and high-rate capability of N-rGO as anodes of lithium-ion battery were attributed to the large number of surface defects caused by the nitrogen doping, which facilitates the fast transport of Li-ion and electron on the interface of electrolyte/electrode.

The life distribution model and accelerated life testing methods of the disc magazine and manipulator were discussed. The small sample determination of truncation test was performed to QY011 and a batch of test data under the accelerated stress at the selection of vibration as the accelerated stress have been obtained. The reliability life index under certain stress level was analyzed through established the accelerated probability weighted Weibull model and inversed power law model for acceleration model. According to the acceleration model and statistical analysis of test data, the QY011 reliability life level of QY011 disc magazine and manipulator under the normal working conditions were calculated.

Phase noise and spurious signals of local oscillator will affect the performance of short-wave receiver. The structure of receiver's front-end part based on DDS is introduced to realize a high-performance local oscillator of short-wave receiver. Then measures were taken to improve the LO's performance, including using external directly frequency multiplier as DDS' clock to improve the purity of frequency spectrum, tracking filter to degrade harmonics and gain control circuit to remain constant amplitude in the desired frequency range. At last, test results show that the above-mentioned measures improve the receiver's performance.

The influence factors of hydrothermal treatment on the formation process of ZnO nanorods are investigated involving with hydrothermal temperature, time and precursor concentration. The as-obtained products were characterized by Scanning Electron microscope (SEM) and X-ray diffraction (XRD), respectively. XRD result indicates that the obtained ZnO nanorods are high-quality single crystals. SEM results indicate that both the diameter and the length of ZnO nanorods increase with increasing the hydrothermal time and temperature. The precursor concentration prominently determines the morphologies of ZnO nanostructure from initial particle morphology to rod-like, and to final slice-like morphology.

In this paper, the TM image of Landsat-5 was used for classification by the method of support vector machine (SVM). The results and precisions of classification were compared between the different parameter combinations. Further more, precisions are compared between the SVM and traditional algorithm. The results indicate that SVM classification algorithm has the advantage of broad parameters range, without prior knowledge of image and samples. The precision of SVM algorithm is much higher than traditional algorithm, especially adapt to the area without in situ measurement.

Design of a digitally tunable tracking preselected filter for improving anti-interference for Ultra Short Wave receiver front-end is proposed in this paper and the characteristics of the preselected filter circuit are analyzed. Then we mainly discuss an inductor-coupled dual resonant structure with better selectivity and anti-jamming and its implementation. Finally, test results are provided, shown the specifications of the circuit are in great agreement with the simulation and design requirements.

To develop low-carbon tourism attraction is conducive to the transformation of tourism industry’s development mode. It can also help China to take the carbon-reducing responsibility in the world, reduce carbon emission and develop low-carbon economy and society. This paper takes Beijing Badachu Park as the case study to analyze the relationship between the development of low-carbon tourism attraction and the tourists’ low-carbon cognition. It shows that there’re two kinds of low-carbon cognition, one is “to know it” and the other is “to do it”. But the reality is there always has some inconformity between consciousness and behavior in low carbon tourism which is bad for the construction of tourism attractions. This article put forward some suggestions to solve this problem: “hardware” transformation, scientifically planning and management, to intervene tourists’ low carbon cognition through “attraction also community” ways, etc.

The corrosion behavior of low carbon bainitic steel with Cu-P alloying in the environment simulating coastal industrial atmosphere was investigated by using dry-wet cycling corrosion test. 09CuPCrNi steel and low carbon bainitic steel without Cu-P alloying were used as comparative steels. The corrosion kinetics and electrochemical impedance spectra of the steels were measured, respectively. The morphologies of rust layers were observed by SEM and the phase constitutes of the rust layers were analyzed by XRD. Low carbon bainitic steel with Cu-P alloying behaves the lowest corrosion rate and the highest resistance of rust layer. Bainite microstructure is responsible for the uniform corrosion and the formation of dense rust layer. Cu-P alloying accelerates the transformation of gamma-FeOOH and Fe3O4 to thermodynamic stable phase alpha-FeOOH, which improves the protective effect of the rust layer.

Submicron-sized monodisperse and spherical poly(N-isopropylacrylamide-co-glycidyl methacrylate)-β-cyclodextrin (PNG-CD) microgels with both thermo-responsive and molecular-recognition characteristics have been successfully fabricated via soap-free emulsion polymerization and subsequent chemical modification method. The thermo-responsivity of the microgels is based on the volume phase transition of poly(N-isopropylacrylamide) (PNIPAM) and the molecular-recognition property is based on the host-guest inclusion complexation of β-cyclodextrin (β-CD) units with specific guest molecules. The as-prepared microgels are characterized by Fourier transform infrared (FT-IR), scanning electron microscope (SEM), and dynamic light scattering (DLS) instrument. When β-CD is introduced onto the PNG-CD microgels, the volume phase transition temperature (VPTT) of resultant PNG-CD microgels shifts about 6 °C to a higher temperature in comparison with that of corresponding PNG microgels. When the β-CD units in PNG-CD microgels recognize 8-anilino-1-naphthal-enesulfonic acid ammonium salt (ANS) molecules in aqueous solution, the VPTT of PNG-CD microgels shifts around 3 °C negatively to a lower temperature. PNG-CD microgels present molecular-recognition induced swelling characteristics at fixed temperature. The results in this study provide valuable information for development of monodisperse and spherical dual thermo-responsive and molecular-recognition microgels which have potential applications in the fields of microscale molecular sensors and actuators and so on.

This paper summarized various adopted widely balancing technology of spindle, specially introduced the principles, structural characteristics, advantages and disadvantages, research and application situations of several on-line balancing devices. Finally, Aiming at the existing problems in the applications of the technologies in spindle dynamic balancing, the article points out the directions in the applications of on-line balance of spindle, and some key problems to be solved in future.

Dynamic impact experiments of man-made rock were carried out with the Split Hopkinson Pressure Bar (SHPB) apparatus in this paper. The impact process was analyzed and the influence of rock porosity on dynamic mechanical behavior was investigated. The stress-strain curves in rock were obtained by the one-dimensional stress wave theory. The curve lays foundation for numeric simulation of rock fracture under impact loading. The damage profiles of rock specimen under the impact loading show that the man-made rock exhibits obvious shear damage under the impact loading because it is a typical porous medium containing large quantities of defects such as pores, cracks and grain boundaries at the microscale. The experimental results also indicated that rock porosity plays an important role in dynamic mechanical behavior.