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Platinum matrix composite is a new type of functional pottery material, which has excellent mechanical, electrical and optical properties. Due to the complexity of the synthesis method and the expensive equipment, the development of cermet material is extremely slow, so that the method to solve the problem is urgently needed. In view of the excellent performance of the Pt-C compounds, by hydrothermal method and high temperature roasting method, a new synthesis method for the composite is proposed using melamine and four platinum chloride at 60 °C by the polymerization reaction with a molar ratio of 20:1. The synthetic of Pt-C compounds provides a new synthesis method and new ideas and at the same time the Pt-C compounds has excellent performance, showing the excellent applications in machining.

Graphene, whose structure is composed of a single-atom-thick sheet of sp2-hybridized carbon atom, provides large specific surface area, excellent mechanical and chemical properties. In this paper, reduced graphene oxide/carbon nanotube (rGO/CNT) composite, which had superior electrochemical performance, was synthesized via a facile, handy and cheap method. Electrochemical tests showed that rGO/CNT composite that the weight ratio of graphene oxide (GO) to CNTs is 7.5 to 1 exhibited the specific capacitance was 346.84 F/g at the current density of 2 A/g in 1 M H2SO4. The good performance of rGO/CNT composite was ascribed to huge surface area of rGO and homogeneous distribution of CNT, which prevented the aggregation of rGO sheets, increased the path of electron circulation and speeded up the electrolyte penetrating into the materials. Therefore, rGO/CNT composite had great potential on supercapacitors.

The experiment adopted the method of cultivating Hydrilla verticillata and algae in coexistence systems to study the inhibitory effect of Hydrilla verticillata on planktonic algae in eutrophic water. The results showed that allelopathic and competition of nutrition inhibitory effect were both affect the inhibition of Hydrilla verticillata on planktonic algae at initial concentration of 105 cells·mL-1, and the highest inhibition ratio on was 79% at undernutrition condition; opposite, allelopathic inhibitory effect played a major role at nutritional sufficiency, the highest inhibition ratio was 39%. Hydrilla verticillata played a role of “promoting with low biomass while inhibiting with high biomass” on planktonic algae, the optimal biological dosage of Hydrilla verticillata on inhibiting planktonic algae at initial concentration of 105 cells·mL-1 was 12g·L-1. Hydrilla verticillata allproduced inhibitory effect on planktonic algae at different initial concentrations, and the greater the initial concentration of planktonic algae, the higher the inhibition ratio of Hydrilla verticillata on planktonic algae.

The cyclic deformation behaviors of hotrolled AZ91 magnesium alloy are studied by asymmetrical cyclic stresscontrolled experiments at room temperature. The ratcheting behavior and fatigue failure mechanism are discussed. Results show that: (1) The ratcheting strain increases sharply with the increase of cycle number at the initial stage, and then tends to be a constant after certain cycles. (2) The fatigue crack initiation and stable propagation regions are flat with lamellar structures, while the unstable propagation and rapid fracture regions are coarse with ductile dimples and tearing edges. (3) The residual twins can be seen as potential damage to fatigue failure of the material, due to its irreversibility of cyclic plastic deformation and damage to grain boundaries.

It investigated in an algorithm for passive ranging algorithm based on the target’s image information along with direction information. It aimed at to avoid the sick solution of the quadratic equation for distance estimation, such as the complex solution, or the negative solution, a novel one variable quadratic equation is proposed for distance estimation. In our method, the distance ratio between two sampling times could be obtained from image matching based on feature points, and combined both the space coordinate of the observer itself and direction cosine parameters of the target to the observer, a passive distance ranging equation is settled. Theoretical analysis shows that when the observer with non-zero displacement in the adjacent sampling times, this passive ranging equation could always be solvable. It illustrated by our reduced mode experiment that the proposed algorithm is simple and feasible, relative ranging error is smaller than the former quadratic equation. It confirmed that under the same observation model, if the observer itself is moving, the distance estimation would be in much simpler mathematical form.

With the rapid development of Chinese economy, the thermal power requirement is increasing not only in industry but also for the civil use in recent years. In China, the main fuel of thermal power is coal. Coal handling system places the consequence in the whole generate electricity system and has significant meaning to the power plant operation. The coal handling system of the thermal power plants has many types of equipment. The environment is vile with complicated control. If we control this system through manual mode, there will appear the imponderable questions. This article through the research of the coal handling system by the management of PLC can determine the long-term safe operation and reduce a mass of human power and material resources. It has the fundamental practical meaning and research value.

As people’s life quality rise continuously, the fitness industry has developed fast. At present, people mainly focus on the improvement and research of fitness bike’s comfort and security, not on the movement manner. Thus it causes the movement process to be drab and boring, which has negative effect on the exercise. Therefore, Shenzhen Institute of Advanced Technology developed a new kind of multifunctional interactive fitness bike. Its characteristic is that both hands and feet can driver it independently, which can add different movement manners. This paper mainly aims at designing a new kind of resistance automatic adjustment system according to its unique drive mode. This system can make the rider obtain smooth and comfortable feel. At last, through the manufacturing and debugging of the prototype of fitness bike, we know this scheme is feasible.

As people’s living pace becoming faster and faster in modern society, a lot of machines which can substitute human beings, such as washing machine, dishwasher, have appeared. These machines can greatly save people the necessary labor times. The automatic cleaning wall mechanism which is studied in this paper belongs to a category of cleaning machine. It aims to clean the body cavity wall of a square. The primary research includes the mechanical structure design, the electrical control system design, and modal analysis for this mechanism in order to avoid resonance phenomena occurred between motors and bodies. At last, via experimental running, this mechanism can move forward according to our predetermined trajectory.

The compressive deformation experiments of 2124-T851 aluminum alloy were carried out over a wide range of temperature and strain rate. An artificial neural network (ANN) model is developed for the analysis and simulation of the correlation between the flow behaviors of hot compressed 2124-T851 aluminum alloy and working conditions. The input parameters of the model consist of strain rate, forming temperature and deformation degree whereas flow stress is the output. A three layer feed-forward network with 15 neurons in a single hidden layer and back propagation (BP) learning algorithm has been employed. Good performance of the ANN model is achieved. The predicted results are consistent with what is expected from fundamental theory of hot compression deformation, which indicates that the excellent capability of the developed ANN model to predict the flow stress level, the strain hardening and flow softening stages is well evidenced.

The purpose of this paper is to investigate the possibility of rod-like Al2TiO5 / α-Al2O3 composites in situ formation via a mechanical activation process. A QM-ISP-4 Planetary Mill was employed to activate mechanically the mixtures of anatase and corundum in air at room temperature for different times. The milled powder mixtures were pressed into platelets and then sintered in air at 1300°C for 3 h. The XRD results showed that only Al2TiO5 and α-Al2O3 phases could be detected in the sintered samples when the activated time reached 30 hours. The SEM observations illustrated the unusual microstructure of Al2TiO5 / α-Al2O3 ceramic composite materials. Abnormal grains with longitudinal length ~10 μm23 transversal length ~1 μm and equiaxed matrix grains of ~3 μm on an average were observed. EDXA proved that the rod-like grains and the fine equiaxed matrix grains were composed of Al2TiO5 and α-Al2O3, separately. The roles of anisotropic grain growth caused by mechanical activation are discussed for the in situ formation of rod-like Al2TiO5 / α-Al2O3 ceramic composite materials.

The purpose of this paper is to investigate the possibility of rod-like Al2TiO5 formation via a mechanical activation process. A QM-ISP-4 Planetary Mill was employed to activate mechanically the mixtures of anatase and corundum in air at room temperature for different times. The milled powder mixtures were then sintered in air at 1300°C for 1 h. The XRD results showed that the milled powder mixtures were completely transformed into Al2TiO5 after sintering, except the mixtures milled for 5 and 10 hours. The SEM observations showed the typical morphology of rod-like Al2TiO5 vary in the range: widths from 0.6 to 1.2 μm, and lengths from 3.0 to 6.0 μm. The rod-like Al2TiO5 formation was attributed to the positive effects caused by the mechanical activation.