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For exploring the corrosion rules of copper-containing low carbon steel under different pH conditions，the electrochemical workstation and metallographic microscope were used to analyze the polarization curves，AC impedance spectra and micro morphologies of ordinary weathering steel (Q345)，copper-containing low carbon steel (0Cu3Cr) and hull copper-containing low carbon steel (0CuAl) in NaCl environments with different pH values.Additionally，the difference in corrosion performance between copper-containing steel and low carbon steel in NaCl environments with different pH values was observed.Results showed the self-corrosion potential of the three samples was higher in the NaCl environment with pH＝12.The corrosion processes of 0Cu3Cr and 0CuAl were controlled by the anodic dissolution reaction，while that of Q345 was controlled by the cathodic reaction.Moreover，the self-corrosion potential of Q345 and 0Cu3Cr at pH ＝6 was slightly greater than that at pH＝8.The charge transfer resistance values of the three kinds of samples were the largest in the NaCl environment with pH＝12.When pH＝6，the pitting pits on the surface of 0Cu3Cr were smaller and less numerous.When pH＝8，the pitting pits on the surface were larger and more numerous.Besides，the corrosion resistance of 0CuAl at pH＝8 was better than that at pH＝6.

In the present work, the hot deformation behavior of two austenitic stainless steels with different nitrogen is studied by conducting compression tests at the strain rates in the range 0.01–7 s−1 and temperatures in the range 950–1150 °C using a Gleeble thermomechanical simulator. Simultaneously, the constitutive relationship is based on the Arrhenius hyperbolic sine equation and constructs the corresponding thermal processing maps based on dynamic material modeling (DMM).The 23Cr7MnNi2Mo0.93N (0.93 N) steel possesses a higher hot deformation resistance and a higher activation energy of deformation (628.39 kJ mol−1) compared to the 23Cr7MnNi2Mo0.45N (0.45 N) steel (315.79 kJ mol−1). Dynamic recrystallization occurs predominantly in 0.93 N steels under the conditions tested, the samples with 0.93% nitrogen content exhibit higher peak stresses and more complex rheological behavior. According to the thermal processing maps, the hot working region for 0.45 N steel is 1020 to 1150 °C at strain rates of 0.01 to 0.1 s−1, while 0.93 N steel is not suitable for processing in the experimental parameter range. [ABSTRACT FROM AUTHOR]

This text was mainly studied the extraction flavonoids technology from Momordia cochinchinensis seeds. The optimum extraction condition was as follows: when the ratio of liquid to solid was 20:1, the ethanol concentration was 90% and the extraction time was 2h. Under this condition, the actual average yield of flavonoids could reach 0.363%.

In this paper, the influence of the combination of last sense codon and stop codon on expression efficiency was studied. By our study, for the last sense codon CCG, the RFI of GFP(CCG) was 2.1 fold when the stop codon was UAA, but in comparison, the RFI was 1.1 fold when the stop codon was changed from UAA to UAG. For last sense codon TAG, the RFI of GFP(TAG) with the stop codon UAG was stronger than that with the stop codons UAA and UGA.

This text was mainly studied the response surface optimization of ultrasonic assisted extraction of flavonoids from Brucea javanica. The optimum extraction process conditions were obtained by color reaction to prove the presence of flavonoids and by response surface simulation and quantification, the optimum condition was: ethanol concentration was 90%, the ratio of liquid to solid was 10:1, and the extraction time was 2h, the total extraction rate was the largest, up to about 1.43%.

Textured soybean protein (TSP) is a product made from cooking and extrusion of soybean protein, which has been widely used in food, feed and other industries. This text made soybean protein isolated (SPI) and soybean protein concentrate (SPC) as the raw materials to produce filamentous protein production. By experiment, the influence of puffing temperature, screw speed and feed rate on the quality of the protein products was studied. Finally it was concluded that when the temperature of the barrel was 152 °C, the screw rotation speed was 119 rpm, the feed rate was 0.426 kg/min, the TSP product had the biggest expansion degree.

The effect of heat treatment on the corrosion resistance and antibacterial ability of 0Cu2Cr carbon steel was studied using scanning electron microscopy, transmission electron microscopy, laser scanning confocal microscopy, and electrochemistry. The results showed that the peak aging state with complete crystal growth and uniform precipitate phase distribution was attained at the aging temperature of 850°C. Both the Cu‐rich phase with an approximately spherical structure and the dispersive Cu‐ordered phase with a B2 structure were observed in the grain boundary and internal crystal and effectively improved the hardness of the steel because of precipitation strengthening. Thus, the corrosion resistance and antibacterial ability of the 0Cu2Cr carbon steel could be improved by aging it at 850°C. [ABSTRACT FROM AUTHOR]

Thus far, research on the corrosion resistance of copper‐containing steel has been limited to Cu content of less than 1%, and the corrosion resistance of antibacterial Cu‐containing steel with Cu content above 3% has not been reported. In this study, 0Cu3 carbon steel (CS), 0Cr15Cu3 stainless steel (SS), and Q345 CS were investigated. The corrosion resistance and corrosive behavior of high‐copper (high‐Cu)‐bearing steel in a marine environment were examined by scanning electron microscopy, energy dispersive spectrometry, X‐ray diffraction, electrochemical impedance spectroscopy, and potentiodynamic polarization. Coupon test results showed that the Cu in the 0Cr15Cu3 SS and 0Cu3 CS can promote the formation of stable α‐FeOOH from γ‐FeOOH in the outer rust layers, and make the rust layers more thick and dense. In the electrochemical experiment, the impedance loop diameters and Rct values of the 0Cr15Cu3 SS and 0Cu3 CS were higher than those of Q345, while the Icorr was less than that of Q345, which indicates that the anticorrosion property of these two types of high‐Cu‐bearing steel was higher than that of Q345. The aim of this study was to define the properties of corrosion resistance and corrosive behavior in high‐Cu‐bearing steels to promote their application in marine engineering. [ABSTRACT FROM AUTHOR]

A kind of coronary stent was made from Nickel-free stainless steel, and the technological process of the stent was studied. A preferable flexible and support force stent was simulated by a commercial finite element code ANSYS with laser cutting, pickling and vacuum annealing. This kind of coronary stent has more superiority. It was also presented that a self designed automatic stent electro-polishing device, which greatly improve efficiency and quality, and the optimization electro-polishing process was put forward.