用萃取—火焰原子吸收光谱法测定金属钛中微量铜和镍

1 试剂所用全部试剂都是试剂纯的.水是重蒸馏水.用纯度为99.99%的Cu和Ni配制标准贮备液,酸度调至0.1M盐酸.用FeC1_3.6H_2O配制Fe(Ⅲ)溶液(Fe0.4mg/m1).所用全部溶剂均未进一步提纯.2 样品制备     

高铌高钒微合金化钢的形变热处理

测定了Ｎｂ－Ｖ微合金化钢形变热处理特性曲线，利用轴向对称试样在恒定应变率下的均匀压缩等温压力加工试验测定了高温时金属的科技特性曲线。利用４个阶段对试样进行情怀定真应变率压缩试验来部分地模拟带钢轧制工艺。不同应变时，载荷是间断的，间断时间越来越短。一个间歇期后，观察了微合金化元素阻碍动态复原过程的能力。通过 微的观察说明最重要的工艺参数是总应变量。     

从奥林匹亚难处理砷黄铁矿精矿中提金的细菌氧化条件

本文着重研究了从奥林匹亚难处理砷黄铁矿精矿中提取金的细菌氧化条件，其中包括ｐＨ值，矿浆密度，滞留时间等因素的影响，试验选用的细菌为氧化铁硫杆菌。     

先进复合材料制造工艺的控制研究

发展了一种施加压力的反馈控制方案,以获得复合材料中预想的树脂含量,在标准的固化制度基础上收到明显改进.这种新的可控复合材料工艺的主要优点是增加了系统对不同工艺参数的可靠性以及预浸料的贮存寿命和工艺适用期.     

Quantitative real-time imaging of myocardium based on ultrasonic integrated backscatter

The integrated backscatter calculation over the full, two-dimensional echocardiographic sector is implemented to produce images from closed-chest dogs. This new real-time integrated backscatter measurement system allows a continuous determination of integrated backscatter from all myocardial regions in the ultrasonic view. By replacing the conventional video processor in a commercial two-dimensional echocardiographic imager with this new real-time backscatter measurement system, it is possible to produce real-time two-dimensional images based on integrated backscatter.     

Electrical stimulation during exsanguination: Effects on the prevalence of blood splash and on sensory quality characteristics in veal

Twenty-four veal calves were stunned with a captive bolt. Twelve calves were shackled by the left, the other twelve by the right hindleg. Approximately 1 min after sticking, six carcasses of each of these subgroups were stimulated electrically with equipment relying on a combined high (3000 V, 0·83 pulses s(-1), 1·5 ms duration) and low 35 V, 14 pulsess(-1)) voltage action. The remaining carcasses were left unharmed. At 24 h post-mortem hindquarters were boned to commercial primal cuts. Surrounding connective tissue and cut-up surfaces of primals as well as certain locations vulnerable for blood splash were further dissected. Neither electrical stimulation nor shackling by either of the hindlegs significantly affected the prevalence and severity of blood splash. Post-mortem factors promoting blood splash and possibly related to electrical stimulation and shackling are discussed. At 7 days post-mortem the sensory meat quality was assessed. In general, electrical stimulation did not significantly affect waterbinding and colour characteristics in longissimus (M. longissimus dorsi) and semimembranosus samples. Sarcomere lengths were similar in stimulated and control groups in longissimus but not in semimembranosus muscle. In both muscles shear force values were lower after electrical stimulation. In general, neither longissimus nor semimembranosus samples excised ipsilaterally from the shackled leg side exhibited differences in tenderness and sarcomere length. It is concluded that shackling by one leg or the other does not interfere with the tenderising effect of electrical stimulation.