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Chlorobenzene (CB) was selected as a representative chloroaromatic to evaluate its oxidation process over a perovskite LaMnO 3 catalyst. It was noted that in catalytic CB oxidation, severe deactivation occurred in the LaMnO3 catalyst. This was mainly ascribed to surface coke deposition (involving long-chain organics) and the loss of redox ability. The byproducts in the oxidation process involved certain polychlorinated chain organics of C2OCl4, C2HCl3, and C2Cl4, which were believed to be generated through nucleophilic substitution at the Lewis acid sites of exposed MnClx or MnOyClz. Modification of LaMnO3 by introduction of CeO2 and HF etching was found to distinctly retard catalyst deactivation . The loaded CeO 2 with enriched oxygen vacancies reduced coke deposition and retained the redox ability of LaMnO3. The HF etching forced the fluoride ions (F−) to replace the surface lattice oxygen, which significantly promoted the mobility of surf-Olatt and bulk-Olatt and facilitated Cl desorption (via a Deacon reaction mechanism) from the catalyst surface, ensuring superior oxidation efficiency and stability for catalytic chloroaromatics oxidation. As calculated, the TOF of investigated catalysts followed the sequence LaMnO3-CeO2-HF (11.58 × 10−5 s−1) > LaMnO3-CeO2 (10.14 × 10−5 s−1) > LaMnO3 (5.44 × 10−5 s−1) at 120 °C in catalytic CB oxidation.

In this article, Sr2+ and/or Fe3+-doped LaMnO3 perovskites were rapidly synthesized using supercritical water (sc-H2O) in a continuous hydrothermal flow reactor. Nanosized perovskites (6–45 nm) with defective structures were obtained, which led to high surface areas (28–67 m2 g−1) and enriched defects. After being subjected to catalytic toluene oxidation, La0.9Sr0.1Mn0.9Fe0.1O3 exhibited superior activity with T50 (i.e., the temperature of 50% toluene conversion) at approximately 213 °C, T90 (i.e., the temperature of 90% toluene conversion) at approximately 236 °C, and the reaction rate constant, k, at 1.47 mL g−1 s−1 (at 180 °C). Such activity was even comparable to that of some noble metal catalysts. H2-TPR, O2-TPD and 18O2-TPSR analyses suggested that both the Langmuir–Hinshelwood and Mars–van Krevelen mechanisms are involved in such a toluene oxidation process, where the dissociation of gaseous oxygen (via the surface oxygen vacancies) and the diffusion of mobile lattice oxygen (to the catalyst surface) in the lanthanide perovskites played a crucial role in determining their toluene oxidation efficiencies. This explained why La0.9Sr0.1Mn0.9Fe0.1O3 that has enriched surface oxygen vacancies and high lattice oxygen mobility (both originating from the structural distortion in sc-H2O reaction) could yield a remarkable performance in catalytic toluene oxidation.

The use of ultrasonic nondestructive testing of material internal defect，ultrasonic signal acquired at actual working spot usually includes large amount of noise.Extraction of the defect characteristic information will be influeced greatly if the ultrasonic signal is not effectively denoised. A new method based on best wavelet packet base is present to denoise and detect the ultrasonic signal. The superiority of new method is verified by simulation examples. Experiment of processing ultrasonic signal which comes from the 45 Steel specimen with flaws has been implemented. The accurate information that characterizes of defect size,location can be extracted from the processing result, the results show that the new method based on best wavelet packet base is in favor of enhancing the degree of accuracy for quantitatively analyzing the defect inside the material.

During the process of conventional DDA circular interpolation, the synthesis feed rate fluctuations often, the machining errors are large also. A new efficient arc interpolation method is proposed in this paper, which uses the principle of DDA circular interpolation, it’s function is optimized and improved, Radius is used as the basis of interpolation feed, the left normalized data and pre-loaded are used also. The simulation result of VB program show that efficient circular interpolation method not only has high efficiency,but also has high accuracy.

A new efficient interpolation algorithm for multi-axis linear linkage is proposed in this paper, which uses the principle of DDA algorithm, its function be extended and improved. the left normalized data is used in this algorithm, the maximum amount of movement is used as the basis for the calculation of speed, the efficiency of the interpolation is improved and the uniformity of speed is ensured. At last machining result are presented, which shows that this algorithm is powerful to machine spherical surfaces and planes.

In a typical arc spray prototyping process, two metal wires was melt by electric arc at certain distance and sprayed to the mold surface with high speed compressed air from the jet. To prevent failures such as deformation and cracking, homogeneous temperature field distribution was required for every spray layer. This can be achieved by optimizing the processing parameters using numerical simulating of the temperature distribution. The 3-D temperature simulating technology in the rapid prototyping process using arc spray was introduced. A 3-D model for temperature distribution was established using finite element method. In this model, arc spray rapid prototyping is considered as a process in which every molten drop moves along the path and overlays one another. The movement of the heat source was defined by a function. The temperature evolution as a function of time and the temperature distribution gradient of the sprayed layer were simulated. A real-time measurement of the temperature field was also conducted using infrared thermal imaging system. Results show that the simulating fits well with the experimental data.

The basic concepts of NURBS(Non-Uniform Rational B-Spine) and its application in the field of CAD / CAM are introduced in this paper. NURBS-based multi-axis Side edge of milling tool path generation algorithm and the Rapid detection of the global collision are introduced in detail. Through computer simulation, the tool path generation algorithm and the Rapid detection of the global collision described in this paper is feasible, the actual process can be applied fully.

AutoCAD is a famous software for moulds design, MasterCAM is a popular soft ware of NC- machining. This paper aims at taking f ull advantages of this two kinds of software to design and manufacture mould. Through the example of designing and manufacturing of cell phone covermould, expound the method and technological process of NC machining by using this two kinds of software.

This paper presents the initial design and implementation of a simple microcomputer with a reduced instruction set, which forms a building block for a parallel multi-microcomputer system. The microcomputer has a 16-bit word size, with each register and data element being 16 bits. It has less than 20 operators. Each microcomputer in the multi-microcomputer system is addressable, and behaves as a combined memory cell and processor that is able to service the LOAD, STORE, and EXECUTE operations. The multi-microcomputer system centers on a 16-bit global address space. An address consists of two parts: the high eight bits define a specific microcomputer, and the low eight bits define a word in that microcomputer. When the top eight bits are zero the address is considered local to the microcomputer. Although a microcomputer can load or store any word in the global address space, an attempt to execute code at an alien address causes execution to transfer to the specified microcomputer. Although the microcomputer design is based on 16-bit units, we ultimately wish to design the simplest microcomputer that is able to handle variable length information.