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This paper explored the electrochemical oxidation of coking wastewater with Ti/RuO₂-IrO₂ anode. The effects of electrodes connections, area-volume ratio and aeration on the removal efficiency were studied and the ammonia removal mechanism was investigated. The results show that the highest NH₄⁺-N and COD removal efficiency and current efficiency are achieved at the area-volume ratio of 14.44m²/m³ and electrode distance of 0.5cm. Unipolar connection is better than bipolar connection. For electrochemical oxidation of ammonia, the chloride ion is the main factor affecting nitrogen removal. NH₄⁺-N is removed mainly by the oxidation of hypochlorous.

This article summarizes the concept and classification of plasma. The application of plasma technology for the treatment of waste gas, waste water and solid waste are also introduced, and future developments of plasma technology in the field of environmental protection are discussed.

Submerged Entry nozzle is one of the key functional refractories for continuous casting and the safe and efficiency of the continuous casting is directly influenced by the properties of ZrO2-C materials located at the slag line of the submerged entry nozzle. In general, a little anti-oxidants such as SiC, Si or B4C will be introudced into ZrO2-C materials and anti-oxidants also influence the corrosion resistance of ZrO2-C materials. So this paper researched the properties especially the corrosion resistance of ZrO2-C materials with SiC, Si or B4C additions. The results show that the properties of ZrO2-C materials are relate to the composition of ZrO2-C materials and the corrosion resistance of ZrO2-C materials have no obvious relationship with other properties such as apparent porosity, bulk density, et al. The addition of anti-oxidants will all decrease the corrosion resistance of ZrO2-C material. The decreasing degree of corrosion resistance by Si is the most and the decreasing degree of corrosion resistance by SiC is the least. The corrosion resistance of ZrO2-C material with B4C addition is relate to the kind of the mold slag. To obtain the ZrO2-C material with excellent corrosion resistance antioxidants should not be added into ZrO2-C materials.

A new kind of optical fiber corylic resin coating was prepared in this paper. The influence of PVC (pigment volume concentration) to the properties of coatings was studied. The best formula was selected. The best coating was painted on the optical fiber. The relationships of the coating diameter and the distances of the centers of the coating layer and optical fiber were studied. It was found that the circle diameter of coating is greater; the distance of centers of circles is bigger. Finally, the optical fiber with this coating was embedded in resin castings. The cross sections were observed under the same heated situation. The results revealed that the coatings embedded in composites used in large aircraft had no change when it was heated. This kind of coating did not need ultraviolet light or heating, and it’s easy to control the thickness and roundness of the coating by controlling the speed of pulling out the optical fibers. This type coating is a kind of simple heat-resistant coating embedded in composite materials used in the large aircraft.

The traditional cars consume high energy and the energy of vibration is wasted. To solve these problems, a new energy recovery damper was designed by analyzing the principle of vibration energy recovery and the advantages of electroactive acrylic elastomer materials. The three-dimensional modeling was finished for the mechanical structure of the energy recovery damper. As an important constituent part of vehicle suspension system, the energy recovery damper was a nonlinear vibration system which contained elastic force and damping force. The system could generate random vibration with the drive of the sources such as pavement roughness and engine. The vibration energy can be recycled and stored into vehicle battery by the energy recovery damper. The energy could be saved by changing the vibration energy into electric energy. The energy recovery damper has the advantages of simple structure and high efficiency.

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.

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.

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.