According to the requirement of the calibration in minimally invasive blood glucose monitoring, a method based on microdialysis was presented to monitor glucose level in interstitial fluid continuously. An experimental system simulating the continuous change of glucose concentration in vivo was built. The influences on recovery of microdialysis caused by flow rate, glucose concentration, and temperature etc. were studied. The results led to the conclusion that the recovery fell by 71.7% when perfusion rate increased from 0.3 μL/min to 3.0 μL/min, while the different concentrations of glucose solutions scarcely contribute to the recovery instead, and the temperatures from 25 to 58 °C caused the recovery to increase by 34.6%.
Relationship between amount of recoverable strain and pre-strain in Fe-25%Mn-4.5%Si-1%Cr-2%Ni shape memory
alloy (SMA) was measured in tensile tests. The results show that recoverable strain increases with increasing pre-strain
lower than 5%, and decreases rapidly when the pre-strain go beyond 5%. By X-ray diffraction, the effect of pre-strain on
volume fraction of stress induced ε martensite (εM) was determined and it was found that amount of εM first keeps
increasing with pre-strain and then reaches saturation when pre-strain is over 8%. Transmission electron microscope
(TEM) observation shows that morphology of stress induced εM for different pre-strain differs greatly and thus has
different influence on shape memory effect (SME) of the alloy. Three types of morphology of εM were observed for
different pre-strain, which are thin εM plates, wide εM bands of multilayer and intersecting εM variants respectively.
Microstructure of an Fe-Mn-Si-Cr-Ni shape memory alloy (SMA) after being TIG (tungsten-insert gas welding) welded
was investigated using scanning electron microscope (SEM) and X-ray diffractometer. The results show that dendrite
crystals composed of cellular sub-structures form in the weld zone due to remelting. There is no obvious change in
microstructure of the heat-affected zone (HAZ) except for some degree of growth of austenite grains. Since both the
weld zone and HAZ consist of single phase of austenite (γ), pre-strain can still induce the γ→ε martensite transformation
in welding joints of the alloy. Effect of TIG welding on shape recovery characteristics of the alloy was examined by
bending tests and it was found that the TIG-welded Fe-Mn-Si-Cr-Ni alloy exhibits almost the same excellent SME as the