盐水介质中Ti12Mo5Ta合金的电化学特性(英文)

比较了未再结晶和再结晶Ti12Mo5Ta合金、未再结晶Ti12Mo合金和工业用纯钛(cp-Ti)在0.9%生理盐水(pH 2.3)中37°C下的电化学行为。从阳极极化曲线中得到了极低的钝化电流密度(10-6 A/cm2),这表明所有样品在酸性0.9%NaCl溶液中具有高的耐蚀性能。采用扫描电子显微镜(SEM)观察样品的表面形貌,发现所有样品表面受到了相同的腐蚀,而且经阳极动电位极化测试后的样品表面没有出现点蚀、裂纹或其它缺陷。使用等效电路模拟电化学阻抗谱(EIS)数据,以表征样品表面且更好地理解Mo和Ta的添加对cp-Ti及再结晶的影响。EIS结果证实,在开路电位下,所有样品在0.9%NaCl溶液(pH 2.3)中产生钝化(极化电阻约为105Ω·cm2)。在37°C时,样品在0.9%NaCl溶液中(pH 2.3)的耐蚀性顺序为:再结晶Ti12Mo5Ta未再结晶Ti12Mo5Ta未再结晶Ti12Mocp-Ti。     

含Mo和Ta作为β稳定剂元素的Ti合金在牙科应用中的电化学行为

研究具有相同Mo质量分数（12%）的Ti12Mo和Ti60Ta合金以及当前常用的Cp-Ti金属生物材料在牙科应用中的电化学行为。采用电化学方法,在37°C下,研究样品在人工唾液以及加氟人工唾液（含0.1%F-）两种电化学媒质中的电化学性能,如开路电位、动电位极化曲线和电化学阻抗。在牙膏、牙科凝胶和牙科冲洗等方面,通常含有氟化物以防止龋齿和缓解牙齿敏感。观察在两种媒质中所有钛合金样品的电化学行为,结果表明：在两种电化学媒质中,Ti60Ta合金具有比Ti12Mo和Cp-Ti更优异的抗腐蚀性能。     

响应曲面法优化伽师瓜皮果胶的微波辅助提取工艺

目的:提高伽师瓜副产物—瓜皮的利用价值。方法:伽师瓜皮为试验材料,经晾晒3d并在烘箱65℃的条件下存放24h,处理后的伽师瓜皮呈薄脆状态时效果较佳。以微波时间、p H值料液比为自变量,分别比较三者对其果胶提取率的影响,应用响应面法进行优化,并验证优化方案。结果:伽师瓜皮果胶的最适提取工艺参数为萃取液p H值为3.5、料液比1∶40、微波加热时间为70s,此时伽师瓜皮果胶提取率为4.83%。结论:该工艺可以有效地提取伽师瓜皮中的果胶。     

The distribution of Enterobacteriaceae and some pathogenic micro-organisms in nonbranded white cheese samples sold in Ankara city

In this research, 75 samples of nonbranded white cheese, presented for sale in small markets from various regions and bazaars in Ankara, were studied. Eighty-six isolates, 71 of which are Gram-negative isolates and 15 of which are Gram-positive isolates, were obtained. These isolates were identified by using bioMérieux API20E and classical methods. Total mesophilic bacteria counts and total coliform bacteria counts were carried out for each white cheese sample. The total average mesophilic bacteria of 75 white cheese samples was 15.5 × 10⁵ cfu/g and the total average coliform bacteria were 13.6 × 10⁵ cfu/g.