Wear Behavior of Plasma Oxidized CoCrMo Alloy under Dry and Simulated Body Fluid Conditions

In this study, CoCrMo alloy was oxidized in plasma environment at the temperatures of 600 ℃ to 800 ℃ for 1 h to 5 h with 100% 02 gas and its tribological behavior was investigated. After the plasma oxidizing process, the compound and diffusion layers were formed on the surface. XRD results show that Cr203, a-Co and ε-Co phases diffracted from the modified layers after plasma oxidizing. The untreated and treated CoCrMo samples were subjected to wear tests both in dry and simulated body fluid conditions, and normal loads of 2 N and 10 N were used. For the sliding wear test, alumina balls were used as counter materials. It was observed that the wear resistance of CoCrMo alloy was increased after the plasma oxidizing process. The lowest wear rate was obtained from the samples that were oxidized at 800 ℃ for 5 h. It was detected that both wear environment and load have significant effects on the wear behavior of this alloy, and the wear resistance of oxidized CoCrMo alloy is higher when oxide-based counterface is used. The wear rates of both untreated and plasma oxidized samples increase under high loads.     

Response surface optimization of the removal of nickel from aqueous solution by cone biomass of Pinus sylvestris

Response surface methodology was applied to optimize the removal efficiency of Ni(II). Pinus sylvestris ovulate cones were used in this study. A 2(3) full-factorial central composite design was employed for experimental design and analysis of the results. The initial Ni(II) concentration (10-30 mg/l), pH (2.5-6.5) and biomass concentration (5-25 g/l) were the critical components of the removal optimized. The optimum pH, m (biomass concentration) and C0 (initial Ni(II) concentration) were found to be 6.17, 18.8 g/l and 11.175 mg/l, respectively. Under these conditions, removal efficiency of Ni(II) was 99.91%.     

绿豆抗豆象遗传的初步研究

绿豆象(Callos0bruchun chinensis L.)是豇豆属豆类作物重要的仓库害虫.本研究通过抗豆象杂交育种后代VC1973A/TC1966 F1、F2和VC1973A/(VC1973A/TC1966 F2)BC1F1及TC1966/(VC1973A/TC1966 F2)BC1F1分离群体的遗传分析,发现绿豆抗豆象性状符合31的遗传分离规律,证明绿豆对豆象的抗性由1对显性单基因(Aa)控制,抗虫性为显性(A),感虫为隐性(a).