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The course of electromagnetic fields and waves has properties of abstract concept, strong theory and complex calculation, thus this course is difficult to study and understand, and then is also difficult to teach. In order to make the understanding of the course easier, MATLAB software is used as a platform in classroom teaching of electromagnetic fields and waves. This paper mainly discusses the electrical field intensity distribution of media sphere materials and the properties of electromagnetic wave propagation with MATLAB software. The optical properties of dielectric-metal core-shell multi-layered nano-shell are also studied with Laplace's equation. To enrich the teaching content and improve a better teaching effect, the optical property of nano-materials and electromagnetic wave propagation are visualized with MATLAB software, which makes the properties of nano-materials and electromagnetic wave propagation understand easily.

One step inverse analysis is widely used in sheet metal forming process, since its effective prediction in a short time. A non-linear equation about unknown displacements from final part to plane part is deduced in one step inverse analysis, and it is often solved by Newton-Raphson method. The initial value of the displacements is quite essential to convergence of Newton-Raphson method. An adaptive triangle mesh on 3D surface equipped with metric frame using advancing front method is presented in this paper to improve condition number of matrix and enhance the convergence rate. Numerical results are showed that one step inverse analysis has faster convergence when the initial displacement is solved by adaptive triangle mesh compared with the part mesh (more triangles on final part), and one step inverse analysis has a well distribution of thickness when initial displacement is solved by adaptive triangle mesh compared with tool mesh (bad-quality triangles on final part).

SnS2/SnO2 nanocomposite was synthesized by a simple in situ hydrothermal oxidation route, and characterized by X-ray diffraction, energy dispersive X-ray spectroscopy, transmission electron microscopy and UV-vis diffuse reflectance spectrum. The as-synthesized SnS2/SnO2 nanocomposite displayed much superior photocatalytic activity to SnS2 and SnO2 nanoparticles in the reduction of aqueous Cr(VI) under visible light (λ > 420 nm) irradiation.

This research evaluated the planing performance of bamboo scrimber boards at three feed speeds and three cutting depths and used two methods to assess the finished surfaces. A macroscopic grade assessment was made according to ASTM D 1666-87 for visible planing defects. The other assessment was a microscopic scale roughness test measuring surface average roughness in terms of GB/T 12472. The visible results showed that the finished surface quality of bamboo resulted mainly in Grades and , with the main defect being torn grain. The two evaluations method showed consistent results in surface quality that the highest percentage of Grade was counted and the lowest roughness value occurred. Compared with the hardwood Sawtooth oak widely used in furniture industry in China, planning quality of bamboo scrimber board is better in terms of roughness.

In this article, integrated AlGaN/GaN cantilevers on (111) silicon substrate are fabricated and characterized. The process started with AlGaN/GaN HEMTs fabrication followed by a series of dry-etch-only MEMS process. To characterize the residual stress distribution, Micro-Raman spectroscopy is used and the residual stress in suspended GaN cantilever is found ~ 90% lower after releasing. A type of micro-bending test is used to characterize the piezoresponse of AlGaN/GaN HEMT on the GaN cantilever. An output current modulation greater than 20% can be observed when the cantilever is vertically downward deflected ~ 30 µm.

This paper describes the experimental results of the relationship between grinding wheel topography and grinding chatter and surface waveness on the precise surface grinding machine. The inner relationship between the grinding chatter and grinding surface waveness has been analyzed. The experimental research results show that the grinding depth is a main factor which affects grinding chatter and grinding surface waveness on the grinding surface. Thus a further exploration has been made in the formative mechanism of grinding chatter and grinding surface waveness.

SiC fibers containing Y and Al were prepared by sintering the amorphous KD-Y fibers at different temperatures from 1200 to 1800 °C. The tensile strength of fibers increases when the sintering temperature increases from 1200 to 1400 °C due to the dispersion strengthening of β-SiC microcrystal and decreases to the lowest point when being sintered at 1600 °C, then rose again with the further increase of temperature to 1800 °C. The tensile strength reached to 2.15 GPa. The oxygen content of KD-Y fibers determined the properties of the sintered SiC fibers and sintering process. Through chemical vapor curing (CVC), the oxygen content was controlled below 7.0 wt% and the tensile strength of KD-Y fibers reached to 3.08 GPa. Further-more, the sintering process of KD-Y fibers was discussed and the grain size of β-SiC grew up with the heat treatment temperature.

A new curing method, chemical vapour curing (CVC) for polycarbosilane (PCS) fibers using unsaturated hydrocarbon (cyclohexene) vapour was studied. The low oxygen content SiC fibers were prepared and when the oxygen content in fibers was lower than 4.0%, the maximum tensile strength reached to 3.8GPa. The relationship between the tensile strength and the oxygen content of the fibers was investigated. The structure and composition of SiC fibers were also characterized by element analysis, FT-IR, XRD and XPS. Compared with that by air curing method, SiC fibers with less oxygen and better mechanical properties were prepared by CVC method.

Microflaws were detected on the cross-section of polymer-derived silicon carbide fibers and their formation mechanism was studied by varying the curing degree and the firing rate. The results show that microflaws decrease in size with increase of the curing degree due to an increased ceramic residue. The results also show that microflaws decrease in size with decrease of the firing rate. No microflaws are detectable when the firing rate is as low as 10K/h. This indicates that the microflaws are the main channels of evolution gases and the pressure of these gases leads to their formation and propagation. So a high curing degree and a low firing rate are both preferred in the preparation of dense silicon carbide fibers.