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A set of experimental system was self-designed and made for liquid phase catalytic oxidation of gas to methanol. It was used to investigate the impacts of catalyst and reaction conditions on catalytic oxidation of gas to methanol in acetic acid solution, and to analyze its reaction mechanism. It has been showed that the yield of the methanol is 1840 μmol under the catalysis of 0.5 g of 0.5% Pd-CuPc/Y and the following conditions: CH3COOH:H2O = 4:1 (v/v), 1000 μmol of p-benzoquinone; reaction time, 3 h; reaction temperature, 150°C; gas composition, 2.5MPa CH4+0.4MPaO2 +0.4MPa N2; in acetic acid solution, catalytic oxidation of mine gas to methanol follows mechanisms of electrophilic substitution and oxidation of reactive oxygen species (ROS).

This paper introduces the reactive power compensation technology in the development of power system. From the new technology of reactive power compensation, controller, capacitor connection mode and switching on-off switch to briefly describes the current situation of the development of reactive compensation technology.

The SiO2-BaO-CaO-MgO-ZnO glass-ceramic (GC) coating was prepared on the surface of the nickel based alloy GH140 by slurry spraying technique. Morphology, phase and elemental composition of the glass-ceramic before or after isothermal oxidation for 96h at 1000°C were investigated by SEM, XRD and EDX,. Results showed that the glass-ceramic was mainly composed of BaSiO4 and MgCrO4, and the amount of them both increased after being oxidized for 96h. Compared with bare GH140, GC/GH140 presented a pretty good antioxidant capacity. Before oxidation, white elongated crystals were homogeneously distributed in the glass phases, and a thin transitional layer had already been formed between glass-ceramic and substrate. During the oxidation process, the surface morphology of GC/GH140 became coarse, and small black Si-rich crystals appeared and well-distributed in the coating. Meanwhile, Cr and Ti in the substrate diffused to the interface, which lead to the formation of an oxide-rich interface that protected the substrate from further oxidation.

Decontamination level and residual amount of polycyclic aromatic hydrocarbons (PAHs) were investigated by ex-situ remediation technologies including biopile, soil washing and thermal desorption in a field level. After the remediation, 16 USEPA priority PAHs were decontaminated from 99.3% to 99.9% for thermal desorption, from 17.9% to 82.1% for biopile and from-27.6% to 84.3% for soil washing. Residual PAHs amount in soils by thermal desorption was below the local soil screening level, differently from that by biopile and soil washing. Especially for high molecular weight PAHs, i.e. 5-6 rings PAHs, residual amount exceeded over the screening lever 4 to 197 times for biopile and 17 to 421 times for soil washing. Additional factors, such as cost, time, operation and maintainance etc. for remedial technology selection and contaminant bioavailability in soil matrix for remediation target values, were proposed to be paid more attention for specific contaminated sites.

Three novel dyes (D1, D2 and D3) containing triphenylamine (TPA) unit as core and bearing different benzimidazole units as secondary electron-donors are designed. The geometries, electronic structures, and electronic absorption spectra of these dyes are studied by DFT and TD-DFT. The optimized results indicate that these dyes are all non-coplanar, which can help to inhibit the close intermolecular π-π stacking aggregation effectively. The lowest unoccupied molecular orbital (LUMO) energy levels of the dyes are higher than the conduction band edge of the TiO2, which ensures a high efficiency of electron transfer from these dyes to TiO2 electrode. As the highest occupied molecular orbital (HOMO) energy levels of these dyes are lower than those of I-/I-3, these molecules that lose electrons could be restored by getting electrons from electrolyte. The absorption spectra of these dyes are simulated, and the calculated results indicate that D3 can absorb more photons than those of D1, D2 and TPAR in the region from 250 to 580 nm, which should have the best performance of photo-to-electric conversion efficiency.

Application of probabilistic risk assessment (PRA) and deterministic risk assessment (DRA) at a coking plant site were compared. By DRA, Hazard Quotient (HQ) following exposure to Naphthalene (Nap) and Incremental Life Cancer Risk (ILCR) following exposure to Benzo(a)pyrene (Bap) are 1.87 and 2.12×10-4. PRA reveals valuable information regarding the possible distribution of risk, and the outputs show that Nap HQ ranges from 6.18×10-7to 6.62 and Bap ILCR ranges from 8.67×10-10to 6.89×10-4. Risk estimates of DRA locates at the 99.59th and 99.76th percentiles in the risk outputs of PRA, indicating the DRA overestimates the risk. Sensitivity analysis was done by calculating a contribution to variance for each exposure parameter and it is found that contaminant concentration in the soil (Cs), exposure duration (ED), soil ingestion rate (IRs) are the most important parameters for risk calculations

Helical rotor is a core component of helical-lobe compressor. Analysis was made on the geometrical properties of tooth curves. Using standard spherical milling cutter on 4-axis NC machine, normal migration method was used to rotor surface processing. Based on the generation characteristics of helical rotor surface, object-oriented design method is used to achieve automatic programming system of helical rotor. The calculation of helical rotor end face profile lines and cutter location point are realized, and over cutting analysis is carried out to generate high efficient numerical control processing program.

The research on key technology of mined-out grouting filling management in large channels is carried out based on the geology and distribution characteristic, according to YUZHOU coal mining area on the main channel of the middle rout in the South-to-North water transfer project. This article describes the formula of the goaf governance width, material liquid ratio of filling and sealing grouting, and studies the drilling and grouting technology and then proposes the methods and standards of grouting quality inspection which combines the comprehensive analysis of geological CT scanning, grouting texting and grouting result of data.

In the process monitoring and fault diagnosis of batch processes, traditional principal component analysis (PCA) and least-squares (PLS), are assuming that the process variables are multivariate Gaussian distribution. But in the practical industrial process, the data observed of process variables do not necessarily be the multivariate Gaussian distribution. Independent component analysis (ICA), as a higher-order statistical method, is more suitable for dynamic systems. Observational data are decomposed into a linear combination of the independent components under statistical significance. The higher order statistics will be extracted and the mixed signals are decomposed into independent non-Gaussian components. Traditional method of ICA has to predefine the number of independent components. This paper proposed an improved MICA method of realizing the automatically choosing the independent components through setting the threshold value of the negentropy. The method can solve the problem of predefining the number of independent components in traditional methods and meanwhile it reduces the complexity of the monitoring model. The proposed method is used to do the process monitoring and fault diagnosis of penicillin fermentation and the results verify the feasibility and effectiveness of the method.

In this research, sub-region curing and mask DPI modification are used to improve the accuracy of MPSL. Because the curing shrinkage at the discrete region does not cause the shrinkage of the entire resin surface, the accuracy of the RP work piece under sub-regional MPSL can be improved effectively. For the optical system error, the accuracy can be improved through the DPI (Dot per Inch) modification. The research results show that accuracy of work piece less than 12mm can be improved through DPI (Dot per Inch) modification. For the work piece above 16mm, the main method which improves the accuracy can adapt sub-region curing procedure. The combination methods of sub-regional exposure and exposure mask DPI modification can significantly improve the dimensional accuracy of parts, and the overall size of the error of parts can be controlled less than 1%.

The digital measurement of free-form surface is the key to machining quality inspection for surface parts, and the basic requirement of digital measurement is how to realize the adaptive distribution of sampling points with the curvature feature. The traditional sampling methods were limited to the surface known mathematical model. This paper was concerned with free-form surface sampling with CAD model. Firstly, an algorithm of extracting data points from free-form surface was proposed, which transformed the free-from surface into intersection lines. Secondly, the B-spline interpolation was utilized to acquire the parameter expression of each line. Then the curvature measure function was defined on the basis of the curvature and the spline mass was determined taking the curvature measure as density. A new sampling method was presented based on dividing the spline mass equally. On this basis, the sampling process for surface was formulated, which realized the adaptive distribution for surface based on CAD model. The computer simulations show that the suggested method can approximate the curves and surfaces with higher precision comparing against other sampling methods.

In this paper, a new analytical analysis method for chaos: exclusion method is used to analyze ferro-resonance in power system. Its basic idea is that for any systems, there are only four different solution types, that is, constant solutions (equilibrium solutions), periodic solutions, almost periodic solutions and chaotic solutions. If the parameter spaces corresponding to the solutions except chaotic solutions are excluded, the remaining parameter spaces are only the scopes corresponding to chaotic solutions, and then the analytical conditions for the chaotic solutions are obtained. This new method has been applied to the chaos analysis of vibrations equation and electronic circuit successfully. The analytical conditions for chaotic ferro-resonance solutions are obtained for the first time in a recently published paper and the conclusions are proved correct theoretically. In this paper, the resulted conditions are simulated numerically and compared with the Melnikov method to identify the efficiency of the exclusion analysis method. Compared with classical Melnikov method, the conclusion of this article shows that the new method is much more accurate than previous analytical method and is suitable for the system with any degree, especially for high dimensions system.

Navier–Stokes simulation is performed on a canard guided spinning projectile for different attack angles and circumferential position angles of canard over the Mach number range of 1.8–2.2. The computational Magnus moment coefficients of test case are validated with available experimental data of a Secant-Ogive-Cylinder-Boattail (SOCBT) configuration at Mach 3, demonstrating that the method can provide an accurate and viable approach for this problem. The aim of the present study is to provide a detailed understanding of the effects of canard with different circumferential position angles on longitudinal aerodynamic coefficients at three supersonic speeds and various angles of attack. And the results show that normal force coefficients and pitch moment coefficients vary periodically with the circumferential position angles of canard.

To solve the problem of the construction of service-oriented software architecture with fault tolerant, the paper proposes SOADL-EH, a novel service-oriented software architecture description language supporting exception handling. With the capability of modeling normal SOA and the provision of software architecture elements such as exception handling services, exception handling connectors and exception handling configurations, etc., this language can separate clearly the exception handling logic from the normal business logic of the service-oriented software architecture layer, which makes up the shortage in exception handling capability of the existing Architecture description language.

The coal dressing method of heavy medium has many advantages, as follows, the strong adaptability on coal quality of raw coal ,high precision of separation, the wide grade range, Craft system simplification, easy to realize the automation and other advantages, which have rapid development trend both at home and abroad. Heavy medium density automatic control system is one of the most important key, that height and stability play a decisive role on the quality of products and production rate for coal production process. In this article, the heavy medium density is accurate measured with the ultrasonic attenuation theory, he law of attenuation is analyzed in the heavy medium density liquid, the relationship between the density and sound attenuation is summarized. And the closed loop automatic control is realized based on which and the separation efficiency is improved, the cost is saved.

Nowadays the resource organization process has forced the investors to consider the candidate enterprises very carefully. To avoid the effect of the mutual relationships between the similar enterprises, it is helpful to evaluate the candidate enterprise comprehensively and objectively. An extension evaluation method for the candidate enterprise is presented on the analysis of the third party logistics enterprises. Firstly the measuring weights are determined using the AHP method; secondly, the dependent function is established, and calculates the qualification degree of each enterprise using this formula, also we should normalize it. Thirdly the optimal degree is calculated to evaluate the enterprise. The enterprise with the highest optimal degree is the most important enterprises for enterprise.