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Golden Guanyin tea from Lishui city, Zhejiang province, is a new variety of Oolong tea with special aromas. To analysis the aroma compounds, two sample preparation methods of tea grinding and water distillation were carried out, then the tea aromas and amino acids were detected. The main aroma compounds were of dimethyl sulfide, butanal, ethyl acetate, butanedial and cyclobutene by the grinding method, as for the distillation method, the aroma compounds detected were of benzeneacetaldehyde, phenylethyl alcohol, benzyl nitrile, Geraniol, indole, cyclopentene, phenylethyl butyrate, nerolidol, methyl jasmonate, 2,2'-dipyridylamine, benzenedicarboxylic acid, cyclopentaneacetic acid, methyl jasmonate ester, dibutyl phthalate and phytol. Golden Guanyin tea samples had 16 kind amino acids, in which glutamic acid and leucine were of 0.047 and 0.041 mg/mL, respectively, and the minimum ones were of cysteine and methionine in concentration of 0.004 mg/mL. The results will be helpful in the quality improvement and production of the new Golden Guanyin tea.

The fluid model driven by an M/M/1 queue with set-up and close-down period is studied. The Laplace transform of the joint stationary distribution of the fluid model is of matrix geometric structure. With matrix geometric solution method, the Laplace-Stieltjes transformation of the stationary distribution of the buffer content is obtained, as well as the mean buffer content. Finally, with some numerical examples, the effect of the parameters on mean buffer content is presented.

The initial buckling displacements are taken as initial conditions to solve the dynamic postbuckling problem. Non-dimensional dynamic postbuckling equilibrium equations denoted by the displacements are derived and solved by use of the finite difference method. The results reveal the regulation that the dynamic postbuckling deformation develops from the initial low step mode to the subsequent higher step modes under elastic compression wave.

In order to make the actual work speed avoid critical speed of the ultra-high speed high temperature abrasion tester, and ensure the smooth running of the tester. Through the establishment of the physical model of testing machine, by using transfer matrix method and matlab software, all order critical speed of the tester is concluded.

The experiment was carried out to measure the effect of membrane treatment on the kinetics of chlorine decay in PE pipes in the water distribution systems. The results revealed that water had the potential to form halomethane compounds with chloroform being the most dominant. The formation of THMs is no longer relatively exponential relationship with the reaction time, but also decided by complex elements, including DOC, pH, conductivity, flow rate, and several other indexes. Since Chloroform (CHCl3) has the maximum concentration of the four THMs, clear understanding of its causes, pathway and mechanism will help to regulate and solve the THMs problem.

The present study was conducted on sensitized 304 stainless steels in 0.5mol/L Na2S2O3solution under the slow strain rate testing (SSRT). To monitor the evolution of intergranular stress corrosion cracking (IGSCC) occurring, acoustic emission (AE) technology was applied in this test. Besides, signal characteristics of different AE sources, including the dissolution along susceptible grain boundaries, the plastic deformation ahead of the crack tip and the mechanical fractures of material ligaments, were identified distinctly with fractography and clustering analysis.

This paper addresses an integrated uncertain programming model for a closed-loop supply chain with manufacturing/remanufacturing hybrid system. The hybrid system is studied under the grey fuzzy uncertainty and grey uncertainty. The hybrid intelligent optimization algorithm integrating the grey fuzzy simulation, neural network and genetic algorithm can optimize the uncertain model. One numerical example is given to illustrate the effectiveness of the proposed model and algorithm.

Gray cast iron specimen was heated to a fixed temperature with high frequency induction heating equipment, then was cooled to room temperature by spraying water to the heated surface. This process was repeated until a crack whose length exceeds 3mm appeared. Transient cyclic heat transfer and stress-strain FEA analysis was conducted to obtain specimen’s stress-strain state, then different LCF life prediction methods based on strain and energy were presented and contrasted, and results showed modified dissipated energy method with maximal hydrostatic pressure was more accurate than other methods. With the help of modified dissipated energy method, the relationship between thermal shock life, highest cooling temperature and cooling speed was studied, and the effect law of highest cooling temperature and cooling heat transfer coefficient on life was obtained.

On the base of the obtained materials and considering the factors of composition features, dynamic mechanism and deformation-motion characteristics, the three-dimension numerical simulation model is generated. And the parameters of Young module, passion ratio and shear strength are obtained. Then the calculation conditions are extracted from the combination of the inducible factors and the displacement features. After that, the deformation failure are simulated by the FLAC3D code, and the results are compared to the monitoring data. The results indicate that the influence of the water impoundment on the stability of the landslide is small, the water descending is large. For the front part monitoring points, the amounts and the curve shapes of the numerical calculation results are accord with the practical ones, but for the monitoring point in back there are only the similarities in the curve shapes, and the amounts are a little smaller.

Application of semiconductor lighting is widespread, so its secondary light distribution design of the LED for lighting plays an important role. For LED road lighting applications, its uniformity of illumination need to meet certain requirements, a freeform surface using freeform optical lens was designed, in the secondary light distribution. Because of the application of freeform lens, LED lighting illumination uniformity has been improved. Lighting simulation and analysis, results indicate that based on freeform lens, LED lighting has good illumination uniformity, and has well research, development and application prospects.

Filter designing is a work that most electronics engineers often do. In order to avoid editing cumbersome and duplicate MATLAB program every time when design a filter, now we design a filter designing software based on hybrid programming of VC++ and MATLAB. Users only need to enter the performance index; you can get to meet the requirements of the filter amplitude-frequency curve, phase-frequency curve, and the coefficients of the numerator and denominator polynomial of transfer function to achieve the filter design. Engine is implemented by VC++ and MATLAB mixed programming, making the interface friendly and program simple.

Taking a landslide in the three gorges reservoir area as an example and considering the seepage field in different time periods with rise and fall of reservoir water level of the eight conditions, we use GEO-STUDIO / SEEP module to establish a seepage model and to calculate the distribution of seepage. The results showed that: the groundwater saturation line appears in the back-phenomenon during a certain range of slope in the rising water level, saturation line was concave shape, and with the rate of increase in water level increased and that concavity gradually increase; the groundwater saturation line appears in the downstream phenomenon during a certain range of slope in the drawdown water level, saturation line was convex shape, and with the rate of decline in water level increased and that convexity increases. The effective simulation studies of the greatly and cyclical fluctuations of water level under the slope seepage field has a certain reference meaning to the landslide control in the reservoir water level fluctuations about reservoir bank landslide.