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The microstructure and mechanical properties of Mg-6Al-1Zn-0.9Y-1.8Gd alloy have been studied by micro-analysis and tensile tests. The results showed that the alloy mainly consists of Mg matrix, Al2Y, Mg17Al12and Al2Gd. The best tensile strength of the alloy was 255 Mpa at room temperature, and the alloy still had the very high mechanical property at high temperature.

The influence of the solution treatment (at the temperature of 500-520°C for 4-12 h) on microstructures and mechanical properties of Mg-Gd-Y-Zr alloy was investigated by means of optical microscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) and Vickers hardness measurement. The as-cast alloy contains a microstructure consisting of α-Mg matrix, Mg5Gd phase and Mg24Y5phase. With increasing solution temperature and time, the quantity of the primary particles (Mg5Gd and Mg24Y5) in the alloy continually decreased, and the degree of recrystallization gradually increased, which result in the gradual decrease of the Vickers hardness of the solution-treated alloys.

In order to evaluate the anti-jamming capacity of the radar net under information warfare conditions, this paper adopts the projection pursuit method to convert the main performance indexes which affect the radar net anti-jamming capacity into one dimension projection value, offers their evaluation and ranking of such indexes and achieves the weights of the these evaluation indexes. This method does not only realize the evaluation of the radar net anti-jamming capacity but also provides a new method to evaluate such a capacity.

Because of the appearance of mobile office and distributed office in Internet communication system, which has brought great opportunities for development of real-time and interactive online evaluation system. In this background, this paper designs an OPC technology which is compatible with multiple internet distributed interface, it can realize the distributed online evaluation. This paper designs a direct switching algorithm procedure of OPC with multiple interfaces, so it can realize the evaluation of interactive and real-time. About the model and the level, this paper uses hierarchical model to evaluate network. Finally based on the evaluation of ideological education online as an example, we conduct the performance of the Internet online system for practice research, it is found that the Internet online evaluation system has well real-time and interactive features, it provides the theory reference for the research of internet ideological and political education.

Because of the coating binder migration in cross-section of coating layer, the binder concentration will be different in z-direction of coating layer, which affect some properties of coated paper. The Paper studied the effects of pigment type, coating color solid content and dying temperature on binder migration and affected factors. The z-direction distribution of the coating binder which was tagged with Br in coating layer and its concentration in coating surface were examined quantitatively by using SEM-EDXA and ESCA analysis. The mechanism of binder migration was also proposed. The results indicated that the degree of binder migration is directly proportional to the drying temperature, that the increase of the ratio of calcium carbonate in the pigment content, coating surface binder concentration increased. The result also indicated that the degree of binder migration was increased with reduced the coating solid content.

The coating binder in cross-section of coating layer will be migrated, the binder concentration will be different in z-direction of coating layer, which affect some properties of coated paper. The paper studied the effects of coating progress on binder migration and affected factors. The z-direction distribution of the coating binder which was tagged with Br in coating layer and its concentration in coating surface were examined quantitatively by using SEM-EDXA and ESCA analysis. During coating process the drying rate, dwell time from coating device to dryer and coating weight affect the binder migration. The mechanism of binder migration was proposed. The results indicated that the degree of binder migration is directly proportional to the drying temperature and coating weight, but reduces with extending the dwell time.

The oxidation and corrosion behavior of Sn-9Zn-1Bi lead-free solder alloys with different P content were investigated by weighing the mass of the alloy, as well as the effects of P on the microstructure. The results indicate that the oxidation resistance and the corrosion resistance of Sn-9Zn-1Bi solder alloy can be enhanced significantly with the increase of P content. The microstructure observations show that P addition into Sn-9Zn-1Bi solder alloy can refine the microstructure and the numbers of dark rod-like Zn-rich phases are decreased with increasing of P addition.

By some assumed conditions and by Fick first law (first used for release behavior of microcapsules), the release dynamic equation of idealized microcapsules in liquid phase was established. With extraction method and spectrophotometer, the light absorbance of extracted liquid was measured, the release dynamics in liquid phase and some relatively release parameters were acquired. The experiment indicated: the release behavior of the CVL core permeated from the wall of microcapsules into the liquid phase matched with zero-order release equation basically.

The coating binder migration and concentration in z-direction of coating layer especially in coating surface influence the coated paper printing properties. The results indicated that with the increase of coating surface binder migration, the coated paper opacity decreases, and the K&N value decreases. The relationship of K&N value and binder concentration in surface of coating layer was linear, which indicated that compared to binder dosage concentration in coating color, the K&N value and coating surface binder concentration has higher correlation. The more uniform the binder distribution in cross section of coating layer, the greater the IGT.

The paper studied the effects of SMA as protective colloid on emulsification and micro-encapsulation process in the preparation of MF-resin microcapsules. The results indicated that pH value and the dosage of the SMA had important effects on zeta value and micro-encapsulation. The SMA dosage, emulsifying time and stirring rate influenced the capsule preparation, mean particle size and particle size distribution of microcapsules. The diameter became smaller with the increase of the amount of protective colloid. The applying amount of the SMA had an optimum value. The zeta potential just after emulsification was much larger than after reaction of MF in the preparation of microcapsules.

The Paper studied the effects of pigments and base paper on binder migration and affected factors. The z-direction distribution of the coating binder which was tagged with Br in coating layer and its concentration in coating surface were examined quantitatively by using SEM-EDXA and ESCA analysis. The results showed that the increase of the ratio of calcium carbonate in the pigment content, coating surface binder concentration increased, and coating surface binder concentration increased with the increase of particle size of pigments. The result also indicated to small base paper absorbency, coating surface has high binder migration level, the coating layer bottom (base paper direction) has low binder concentration. To high absorbency base paper, the opposite is true.

The paper studied the microcapsule particle size, size distribution and its influencing factors with melamine formaldehyde resin (MF-resin) as wall and CVL as core. The results indicated that the microcapsules mean particle size decreased, size distribution became narrow with the increase of emulsifying time and shear rate. Low pH value would make the microcapsules have rough surface morphology and large particle size.

The Paper studied the effects of coating color on binder migration and affected factors. The z-direction distribution of the coating binder which was tagged with Br in coating layer and its concentration in coating surface were examined quantitatively by using SEM-EDXA and ESCA analysis. In coating colors the coating solid content, the binder dosage and type affects the binder migration. The mechanism of coating color on binder migration was also studied. The results indicated that the degree of binder migration was increased with reduced the coating solid content or added more dosage of coating binder. In low dying temperature the SB-latex was prone to migrated to coating layer surface than starch, the opposite is true in high dying temperature.

The paper studied thermal properties of MF-resin microcapsules. The paper established the non-liquid release dynamics equation in ideal mode. The results indicated at 400°C or so microcapsules began to severe weight loss, which explained the heat resistance of microcapsule could completely satisfy the requirement of coating production process. The results also showed the microcapsule thermal weight loss was in line with zero-order release before 373°C, and after 373°C accorded with first-order release dynamics equation.

The paper studied the preparation and micro-encapsulation of pressure sensitive essence microcapsules with MF resin and UF resin as double wall by using the in situ polymerization method, and the optimal preparation conditions were also studied. The microcapsules were characterized on structure, morphologies, thermal properties, mean particle size and size distribution. The experiment illustrated that the wall of microcapsule consisted of the MF resin and the UF resin had been synthesized in the process of preparation, the essence oil was encapsulated into the microcapsules, the mean particle size and size distribution was well-proportioned and narrowed respectively, the particle morphologies were single core and global, the wall was hermetically sealed.

The coating binder migration and concentration in z-direction of coating layer especially in coating surface influence the coated paper printing properties. The results indicated that with the increase of coating surface binder migration, the coated paper opacity decreases, and the K&N value decreases. The relationship of K&N value and binder concentration in surface of coating layer was linear, which indicated that compared to binder dosage concentration in coating color, the K&N value and coating surface binder concentration has higher correlation. The more uniform the binder distribution in cross section of coating layer, the greater the IGT.

The electromagnetic technology of drying Paper is that we use the principle of electromagnetic heating to dry paper, which is a new paper drying technology and quite different from the traditional steam drying . This thesis is based on the principle of electromagnetic induction, combined with technical requirement of paper drying. We used the AutoCAD software design a laboratory drying device with electromagnetic, and analyzed various parts of the selection and structure, by using UG software solid modeling, assembly modeling and other modules design a three-dimensional simulation of the various parts of the electromagnetic dryer device. The simulation graphics shown that the simulation design of electromagnetic dryer is more success, which can meet the requirements of drying paper evenly.

Paper electromagnetic drying technology is a new paper drying technology different from traditional steam drying. Today, environmental pressure deteriorating, energy crisis approaching, doing researches on paper electromagnetic drying technology has a special meaning, especially to high speed toilet paper machine which is truly needed and has a vast developmental potential. This thesis is based on electromagnetic dryer and steam dryer study. And the changes measured in the experiment at diverse temperatures and quantities in the experiment has shown a higher efficiency of electromagnetic drying technology than conventional steam drying technology.

By use of ANSYS software, Without coated high temperature resistant coating and coated with high temperature resistant paint two model to simulate heat transfer analysis, so as to explore the preparation of the high temperature resistant coating insulation heat preservation effect.

Experimental choose methyl-trichlorosilane, di-methyl-dichlorosilane and phenyl trichlorosilane synthetic organic silicon resin, add white mica powder, aluminum silicate, titanium pigment, zinc phosphate as packing, system high temperature insulation coating. For after high temperature resistant coating surface coating of tin model coating physical mechanical properties and high temperature resistant, heat insulation temperature difference of performance test, the results indicate that the system of high temperature resistant coating resistant to 400 ~ 500 °C high temperature, and has good high temperature resistance, heat insulation performance, etc.

Zinc oxide (ZnO) nanorod arrays were fabricated on ZnO:Al seeded Si substrates with various reaction temperatures using a low temperature hydrothermal method. The morphology and structure of ZnO nanorod arrays were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). It reveals that the ZnO nanorods grow vertically on Si surface with (002) preferential orientation. The transmittance spectra show the ZnO nanorod arrays fabricated at low temperatures have high transmittance in the visible region and decrease with reaction temperature increasing. Moreover, the same trend was also observed in the reflectance spectra of the ZnO nanorod arrays. The optimal reaction temperature is of 120 °C for ZnO nanorod arrays with high transmittance (~80%) and low reflectance (~10%) in the visible region. The superior optical properties make ZnO nanorod arrays promising for applications as transparent electrodes.

The 5CB liquid crystal as defects will be introduced to one dimensional photonic crystal, taking advantage of temperature property of liquid crystal refractive index, the transmission spectrum of one dimensional liquid crystal defect photonic crystal defect modes was researched by the transfer matrix method(TMM). The numerical results indicated that when the temperature went up, one dimensional liquid crystal defect photonic crystal defect modes removed towards the long wavelength. When the temperature increased from 273k to 320k, the defect modes wavelength from 5121nm drifted to 5508nm, the wavelength shift was 387nm and the maximum of temperature sensitivity was 10.85nm/K, it was also observed that the temperature sensitivity decreased as the temperature increased.

Low pressure die casting (LPDC) process of a copper-alloy tap was simulated by the finite element software ProCAST. The casting defect and its reason were analyzed. The optimized design was discussed and the simulation was validated against the low pressure die casting experiment. Results showed that the main defect is misrun and its reason is that the melt solidifies too fast. It’s well solved by increasing the wall thickness of the relational pipe properly. The result agrees with the experiment.

Pumpkin（Cucubita pepo L.）seedlings were exposed under different low temperature-light regimes to investigate the responses of photosynthesis and chlorophyll fluorescence to the stress. The results indicated that the contents of chlorophyll increased at first day after treatment and then decreased under special temperature(15/5、20/10、25/15°C )and poor light(50、150、250μmol•m-2•s-1).The net photosynthetic rate, evaporation rate, stomata conductance and intercellular CO2 concentration increased one day after treatment and then decreased, stomata limitation increased above15/5°C special temperature and special poor light. However, under 15/5°C temperature and special poor light, the net photosynthetic rate, evaporation rate and stomata conductance decreased, and intercellular CO2 concentration increased stomata limitation increased in 4 days after treatment then decreased. Ft、Yield(F/Fm’)、qP decreased under special temperature and poor light.The change of these parameters were less under the light density of 50μmol•m-2•s-2 than other light densities, which means that poorer light reduced the sensitivity of pumpkin to low temperature and increased the photochemical activity of PS, but the photochemical quenching (qP) decreased and the non-photochemical quenching(qN) increased at the same time.

Measurement System Analysis is of vital importance in a Six Sigma project. Variable measurement system takes the advantage of being practical and efficient. This paper focuses on the effect of sample size selection on error estimation of repeatability and reproducibility(R&R). After the discussion about the interval estimation of relevant statistics of R&R, this paper continues to analyze how the confidence interval is influenced by the number of operators, the number of samples and times of repeating measurements and a reasonable sample size in assessing the R&R of a measuring system is established for more effectiveness and efficiency.

A series of polyurethaneurea (PUU) nanocomposites based on clay-like sepiolite (Sp) with the modification of γ-aminopropyltriethoxysilane (KH550) were prepared via in situ polymerization from poly(propylene glycol), tolylene-2,4-diisocyanate (TDI) and 3,3'-dichloro-4,4'- diamino-diphenylmethane(MOCA). Morphology and structure of nanocomposites were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The results indicated that KH550-Sp was dispersed homogeneously in the PUU matrix, which facilitated the formation of chemical bonds between KH550-Sp and the hard segment of PUU. The thermostability and mechanical properties were studied by the thermogravimetric (TG) analysis and tensile tests. The results showed that the onset decomposition temperature and tensile strength of nanocomposites was higher than those of pure PUU.

A hierarchically porous zeolite ZSM-5 is prepared under hydrothermal conditions by using hexadecyltrimethoxysilane as inhibitor and template. The physical and acid properties of the hierarchically porous ZSM-5 are characterized by XRD, SEM, N2 physisorption and NH3-TPD techniques. Benzene alkylation with methanol is carried out with both conventional and hierarchically porous ZSM-5 in a fixed bed reactor. The creation of mesoporosity in zeolite ZSM-5 promotes benzene conversion and xylene selectivity with respect to conventional counterpart.

According to the quality problems in one gear enterprise, the DMAIC method which is the core application of the six sigma theory is used to improve the quality of the spiral bevel gear, and the quality data is analyzed by using Minitab software. Firstly, the quality problem is defined in accordance with the DMAIC procedures and the main reasons for quality problems in spiral bevel gears are determined. Secondly, measurement systems and process capability are analyzed. Then, we set a specific program for the improvements for the main causes of quality problems. Through the successful implementation of this project, the quality of spiral bevel gears is greatly improved, and the production cost is greatly reduced. The effect is very significant.

The morphology and growth of the intermetallic compound (IMC) formed between liquid Sn-9Zn eutectic solder alloy and Cu at 220-260°C was investigated. Experimental results showed that γ-Cu5Zn8 was present at the Sn-9Zn/Cu interface as the reaction product. The IMC layer growth follows the parabolic-growth law, which indicates that the growth of the IMC is controlled by the diffusion mechanisms. The activation energy of γ-Cu5Zn8 layer growth for liquid Sn-9Zn reacting with Cu substrate is determined as 50.5 KJ/mol.

Essence oil is difficult to microencapsulate and difficult to envelop into wall to prepare pressure sensitive microcapsules. With styrene maleic anhydride copolymer (SMA) as the protective colloid, the paper studied the effects of protective colloid and micro-encapsulation of pressure sensitive perfume microcapsules with melamine formaldehyde resin (MF) and urea formaldehyde resin (UF) as double wall first time by using the re-in situ polymerization method. The microcapsules and emusion process were characterized on morphologies, mean particle size and size distribution, zeta potebtial, wall thickness of microcapsules. It was found that the SMA seemed to be suitable for the emulsification and preparation of microcapsule with MF-UF resin as double wall containing essence oil. The results indicated the S/M mole ratio in MSA molecules affected the preparation and quality of microcapsules, pH value and the dosage of SMA had important impact on zeta value and encapsulation in the process of polymerization. The stirring time and stirring rate in emulsification process with MSA as protective colloid influenced the mean particle size and particle size distribution of microcapsules, SMA was one of the components of microcapsules, SMA amount used affected the mean particle size, size distribution and thickness of microcapsules.

Boric acid (H3BO3) is often used for cooling the heat in nuclear power plant. Though the drastic measures have been taken, the potential leakage still can not be fully eliminated. Therefore, an attempt to understand the durability mechanism of RC subjected to boric acid is of vital importance. In this paper, specimens cured in a standard moist room at a temperature of 20 ±3 °C after 28days were immersed in three different concentration of boric solution (2000ppm, 8000ppm, 30000ppm) artificially simulated to accelerate the corrosion of acid environment. The hydration products are investigated. Microstructure of reinforced concrete on the surface, 2cm and 4cm away from the surface at ages of 60, 90 and 150 days are examined using X-ray diffraction (XRD) and scanning electron microscope (SEM) respectively. Results indicate that main hydration product is Ca(BO2)2,boric acid corrosion to concrete surface can only be detected from the specimens in 30000ppm solutions at the ages of 150 days and its effect is slight. However, the inner part of the concrete was not affected. The results of XRD coincide with those of SEM.

According to the quality problems in one saw blade enterprise, six Sigma theory and method are used to improve the quality o f saw blades, and establish the 6σ DMAIC improvement model. Six sigma DMIAC procedures are applied to define the problems and set at target for improvement, the main quality are investigated， and measurement systems and process capability are evaluated. Then, we set a specific program for the improvements. At last, the project is successfully implemented, result shows that failure rate reduced to 0.3%, DPMO dropped below 160, and the process capability is improved largely.

Many natural and synthetic dyes present in industrial effluents are resistant to degradation by conventional treatments. Decolorization of indigo carmine were carried out using a newly isolated ligninolytic fungus strain Ganoderma weberianum TZC1. This strain was shown to decolorize indigo carmine efficiently; the optimal pH and temperature were pH 5.0 and 33°C. A decolorization efficiency of 93% was achieved by cultivation for 1 h at an initial dye concentration of 20 mg/L. Furthermore, G. weberianum was shown to be used efficiently and repeatedly in repeated-batch decolorization operations with the mycelia pellets at the different ages. Our results suggest that G. weberianum has promising applications in dye-containing wastewater decolorization.

The Lord of the formula of disjunctive normal form is an important content in propositional logic. When the propositional variable is large, the paper gives a formula for the main disjunctive normal form of simple method.

The electrical resistivity of liquid PbSnBi alloy has been precisely measured by the Direct Current (DC) four-probe technique in our experiment. It was found that the electrical resistivity-temperature (ρ-T) curves changed discontinuously at several-hundred degrees above liquidus. However, the ρ-T curves was linear before this turning point with increasing temperature. Moreover, the ρ-T curve of the different composition alloys showed different turning points. The anomalous behavior of electrical resitivity indicates the alteration of the electron transport properties and the mean free path LZ of conduction electrons, since resistivity as one of the physical properties sensitive to the structure and this discontinuous alteration induced by temperature suggests the liquid-liquid structural transition taking place in PbSnBi melts. This present Letter makes a beneficial attempt at studying electrical resistivity to investigate liquid-liquid structural transition.