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This paper presents foaming behaviors of PPEK blown with supercritical CO₂. The cell density and cell size of PPEK at various process conditions were studied. The experimental results indicate that saturate pressure, foaming temperature and suitable foaming time can provide a positive impact on improving the cell morphology of PPEK foams.

Defect diagnosis of rolling element bearings operating under time-varying rotational speeds entails order tracking and analysis techniques that convert a vibration signal from the time domain to the angle domain to eliminate the effect of speed variations. When a signal is resampled at a constant angular increment, the amount of data padded into each data segment will vary, depending on the rate of change in the rotational speeds. This leads to changes in the distance between the adjacent impulse peaks, and consequently, the result of order analysis. This paper presents a quantitative analysis of key factors affecting the accuracy of order analysis on rolling element bearings under variable speeds. An analytical model is established and simulated. The effects of speed variation, instantaneous speed, angular interval between impulses, and the rising time of impulse are specified. It is concluded that the results of order analysis will be smaller as the rotational speed increases, and becomes larger when the speed decreases. Furthermore, the error is larger under low speeds than high speed.

With the knowledge of heterogeneous characteristics of thermal barrier coating materials at mesoscopic level, a coupled thermo-mechanical-damage (TMD Model) model was introduced and used to numerically quantify the thermal stresses and crack development of in thermal barrier coatings (TBCs) composite subjected to decreased temperatures. The effect of different surface precrack morphologies, such as precrack length and precrack density, on an interface crack subjected to thermal loading caused by a temperature change is presented. It provides us with a more sensible physical intuition and a more accurate mathematical for optimizing the design and the processing of ceramic coatings subjected to the coupled thermal-mechanical loading.

We evaluated the effects of silicon , potassium, and calcium on the salt-tolerant plant Halocnemum strobilaceum (Pal.l) Bie under salt stress. The experimental treatments consisted of a NaCl-only treatment (150, 450, or 900 mmol/l NaCl), a complex salts treatment (NaCl with K⁺, Ca²⁺ ,andSi⁺at total concentrations of 150, 450, or 900 mmol/l;(Na⁺:K⁺:Ca²⁺ :Si⁺ =1:0.03:0.14:0.004), and a control with no complex ions or NaCl. After 20 and 60 days of treatments, we investigated activities of the major antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD), as well as succulence and the contents of malondialdehyde (MDA), proline(Pro) and glycine betain (GB). We found that additions of K⁺ , Ca²⁺ , and Si⁺ partially alleviated the negative effects of salinity stress by increasing the salt tolerance of the plant. The improved salt tolerance was associated with increased Pro, GB,and increased activities of SOD, CAT, and POD,and decrease MDA. In contrast, the NaCl-only treatments caused marked decreases in succulence and soluble protein contents. The results of these experiments suggest that K⁺, Ca²⁺ , and Si⁺ can alleviate the damaging effects of salt on H. strobilaceum by preventing oxidative membrane and oxidant enzyme activities damage, and that they may be associated with osmotic adjustment.

Copper Ferro Alloys (CFAs) have an excellent shielding effect in the electromagnetic field, as well as the similar good conductivity and ductility with copper, and strong magnetism and toughness as analogous to iron. Consequently, it is considered to be novel structural and functional materials with huge development potential and wide application foreground. The influence of the content, size and distribution of Fe phase in the Cu matrix on the electromagnetic shielding property of CFAs is crucial. In the present study, CFAs with various Fe content were fabricated via powder metallurgy (P/M) combining with deformation processing. The microstructure, electrical conductivity, magnetic and mechanical properties of CFAs were investigated by optical microscopy (OM), scanning electron microscopy (SEM), X-Ray diffraction (XRD), and tensile test. The results indicated that P/M CFAs with the homogenous and fine in-situ Fe particles showed better comprehensive performance compared to those prepared by conventional casting. Based on the microstructure observation, mechanical properties were discussed.

Power gating has become a popular technique to reduce the ever-increasing leakage power for commercial microprocessors or SoCs, however the wakeup energy and delay cost harm its performance. This paper proposes a fast reactivation scheme to reduce the transition delay and energy. The experiment results show that, comparing to the traditional power gating implementation, it can achieve 19.66% reactivation energy reduction, 9.28% peak leakage reduction, and 23.36% wakeup delay reduction, at the cost of 2.75% area increasing.

This document explains and demonstrates how to prepare your camera-ready manuscript for Trans Tech Publications. The best is to read these instructions and follow the outline of this text. The text area for your manuscript must be 17 cm wide and 25 cm high (6.7 and 9.8 inches, resp.). Do not place any text outside this area. Use good quality, white paper of approximately 21 x 29 cm or 8 x 11 inches (please do not change the document setting from A4 to letter). Your manuscript will be reduced by approximately 20% by the publisher. Please keep this in mind when designing your figures and tables etc.

Equivalent magnetic circuit method is a rapid calculation method used in magnetic circuit simulation. But for a long time this method can’t be used widely because the algorithm is not general and there is no commercial software developed for this method. In this paper, general software for magnetic circuit calculation was developed using LabVIEW language. Quasi-Newton algorithm was used in solving nonlinear Kirchhoff equation of magnetic circuit in this software. The project file in this software can be shared freely in different calculations. This software is expected to save the time-cost in the design of new product.

The concentration and distribution features of MTBE in the atmosphere in Shenzhen were studied by analyzing samples which were collected in three consecutive days. In this study, pre-concentrator technology and gas chromatography were used. The result showed that the MTBE could was detected in atmosphere of the Shenzhen, and the range of its concentration was from 0.086 - 1.453μgm^-3, including the daily average concentration of 0.662±0.334μgm^-3 in industrial area, 0.331±0.216μgm^-3 in commercial residential area, 0.258±0.154μgm^-3 in tourist area, and 0.158±0.045μgm^-3 in background area. The MTBE concentration in industrial area was 2 times of the commercial residential area, 2.6 times of tourist area and 7 times of the background area. These differences were statistically significant (p<0.008) by the Kruskal-Wallis Test. The MTBE concentration was the highest during one day in the period of 17:00-19:00 of industrial area, which was 0.716±0.306μgm^-3. However, the MTBE concentration in the commercial residential area and tourist area were highest in the period of 11:00-13:00, the MTBE concentration were 0.394±0.224μgm^-3 and 0.446±0.069μgm^-3 respectively. In the workday, the industrial area and commercial residential area were higher compared to the weekend, and the tourist area showed opposite trends, but no matter the comparison of hour average concentration or the workday and weekend, the difference were not statistically significant. It was concluded that the MTBE concentration in atmosphere environment in Shenzhen has the typical spatial specificity because of the different source of MTBE, but has no the time specificity.

Oviductus rana is a traditional medicinal product of Jilin province, China. The objective of this study was to observe the effects of the oviductus rana hydrolysate on the immune functions of immunosuppressed mice. For the purpose, this product was hydrolyzed by the combination of papain and compound proteases for which the optimum conditions of hydrolysis were also achieved. The optimum hydrolysis conditions found in this study were: composite enzyme concentration 4%; temperature 50 °C; time 4 h. The results showed that the coefficients of spleen and thymus were increased in the dose groups (P<0.05) whom oviductus rana hydrolysates were given in different concentrations as compared to the model group (without oviductus rana hydrolysate). These parameters increased as a function of concentration of oviductus rana hydrolysate. Carbon particle clearance index were also higher in the dose groups than that of model group and control. This index was the highest in the high dose group and increased as a function of dose of oviductus rana hydrolysate. The ability of macrophage as well as the delayed type hypersensitivity increased significantly in the dose groups (P<0.01). Meanwhile, the contents of IgM and IgG were also raised (P<0.01) in middle and low dose groups whereas decreased in high dose groups. It is found that oviducts rana hydrolysate had a marked effect on the immunity of immune-suppressed mice.