Electron beam deposition and characterization of thin film Ti-Ni for shape memory applications

Thin film of Ti-Ni alloy has a potential to perform the microactuation functions required in the microelectromechanical system (MEMS).It is essential, however, to have good uniformity in both chemical composition and thickness to realize its full potential as an active component of MEMS devices.Electron beam evaporation technique was employed in this study to fabricate the thin films of Ti-Ni alloy on different substrates.The targets used for the evaporation were first prepared by electron beam melting.The uniformity of composition and microstructure of the thin films were characterized by electron probe microanalysis (EPMA), Auger electron spectroscopy (AES), X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM) and transmission electron microscopy (TEM).The mechanical property of the thin films was evaluated by the nano-indentation test.The martensitic transformation temperature was measured by differential scanning calorimetry (DSC).It is confirmed that the chemical composition of deposited thin films is identical to that of the target materials.Furthermore, results from depth profiling of the chemical composition variation reveal that the electron beam evaporation process yields better compositional homogeneity than other conventional methods such as sputtering and thermal evaporation.Microstructural observation by TEM shows that nanometer size precipitates are preferentially distributed along the grain boundaries of a few micron size grains.The hardness and elastic modulus of thin films decreases with an increase in Ti contents.     

Entrapment of nutrients during cholesterol removal from cream by crosslinked β-cyclodextrin

This study was designed to elucidate the quantities of nutrients entrapped during cholesterol removal from cream by crosslinked β-cyclodextrin (β-CD, 4–12%, w/v) and to evaluate the amounts of the residual β-CD in cholesterol-removed cream treated by crosslinked β-CD. The content of lactose in the control cream (without the treatment by crosslinked β-CD) was 2.74%, and the amounts of lactose entrapped by crosslinked β-CD ranged from 0.00 to 0.03%. The total amounts of the entrapped short-chain free fatty acid (FFA) and free amino acid (FAA) ranged from 0.04 to 0.12 ppm and from 0.37 to 0.48 μmol/mL, respectively. The amounts of the entrapped water-soluble vitamins (L-ascorbic acid, niacin, thiamine and riboflavin) ranged from 0.01 to 0.05 ppm, from 0.01 to 0.05 ppm, from 0.00 to 0.04 ppm and from 0.02 to 0.05 ppm, respectively. The entrapped amounts of nutrients mentioned above were not remarkably affected by the concentrations of crosslinked β-CD (4–12%, w/v). The very small amounts of residual β-CD in the cholesterol-removed cream were measured (1.86–6.11 ppm). Based on the data obtained from the present study, it is concluded that the amounts of entrapped nutrients were negligible during cholesterol removal from cream by crosslinked β-CD, and the amounts of residual β-CD in cholesterol-removed cream were trace.     

Improving Detection of Vibrio vulnificus in Octopus variabilis by PCR

PCR methods can detect foodborne pathogenic bacteria with simplicity, specificity and speed. In order to improve sensitivity and speed of PCR methods for detection of Vibrio vulnificus in small octopus homogenate, several media and culture conditions were compared. Modified brain heart infusion media containing 2% NaCl and adjusted to pH 8.0 and 30°C was most effective for enrichment of the bacteria. Procedures affecting the efficiency of template DNA extraction and target DNA amplification were also optimized. By these combined efforts, a PCR procedure capable of detecting V. vulnificus as low as 10 cells/mL within 10h was developed.     

Evolution of strain states and textures during roll-cladding in STS/Al/STS sheets

The evolution of strain states and textures during roll-cladding of three plies of sheets comprising ferritic stainless steel (STS), aluminum (Al) and ferritic stainless steel was investigated by measurements of crystallographic textures and by simulations with the finite element method (FEM). Because the deformation mainly occurs in the Al layer during roll-cladding, the present investigation was focused on the Al layer located at the middle of clad samples. Roll-cladding of STS/Al/STS sheets led to the development of a strong through thickness texture gradient in the Al sheet which was characterized by shear textures at the surface layer and rolling textures at the center layer. The temperature of the cladding operation played an important role in the evolution of textures.     

Effects of poly‐γ‐glutamic acid on the physicochemical characteristics of skim milk yoghurt

The physicochemical and sensory properties of skim milk yoghurts containing poly‐γ‐glutamic acid (PGA) at different levels (0.0025, 0.005 and 0.01%) were evaluated. Addition of PGA up to 0.01% to reconstituted skim milk (11%, w/v) did not affect the growth of lactic acid bacteria or the development of titratable acidity in yoghurt, whereas full‐fat control yoghurt had reduced acid production. No changes were found in viable cell counts of PGA yoghurts during storage (4 weeks at 4 °C). The addition of PGA (0.005%) significantly decreased syneresis in skim milk yoghurt and did not cause any undesirable effects in sensory acceptability.     

Anticancer activity of lactoferrin isolated from caprine colostrum on human cancer cell lines

In the present study, lactoferrin was purified from caprine colostrum and its anticancer effects were investigated on various cancer cell lines, including lung, colon, cervix, stomach and breast cancer cells. The caprine lactoferrin (CLF) was purified by ultrafiltration and sequential chromatography using a CM-Sephadex C-50-120 ion-exchange column and affinity chromatography on Hi-Trap^TM Heparin HP. The purified CLF exhibited antiproliferative effects on the five tested cancer cell lines in a dose-dependent manner, with 20–30% survival as compared to the control. Interestingly, the most intense inhibition of cell growth was observed on the ZR-75-1 breast cancer cells (IC₅₀ = 27.5 µg/mL). Our findings suggest, for the first time, that purified CLF from caprine colostrum may constitute a novel anticancer agent for the food industry.     

Effects of die geometry on variation of the deformation rate in equal channel angular pressing

The deformation behavior within the deformation zone of a workpiece during equal channel angular pressing (ECAP) was investigated using the finite element method. The effects of die geometry on the variations of normal and shear deformations were studied with a deformation rate tensor (D). The zero dilatation line, at which the normal components (D₁₁ and D₂₂) of the deformation rate tensor (D) are zero, in the die coincided with the line of intersection of the two die channels irrespective of die geometry such as curvature angle (Ψ) and oblique angle (Φ), while the maximum shear line, at which the shear components (D₁₂ and D₂₁) of the deformation rate tensor (D) have maximum value, is dependant on the die geometry     

Orientation rotation behavior during in situ tensile deformation of polycrystalline 1050 aluminum alloy

Microstructural evolutions and orientation rotation behavior taking place during uniaxial tensile deformation at room temperature are studied in polycrystalline 1050 aluminum alloy. Specimens are elongated in an in situ deformation stage equipped in a high-resolution electron backscattered diffraction (HR-EBSD) system. Variations in grain boundary characteristics, such as misorientation and grain boundary distribution, during in situ tensile deformation are analyzed statistically using HR-EBSD. Orientation rotation behavior in individual grains is traced during the whole deformation process. A large number of grains in polycrystalline 1050 aluminum alloy rotate during deformation and are divided into subgrains due to multiple slip. The plane normal directions of individual grains show no remarkable tendency of the orientation rotation during in situ tensile deformation, while the orientation rotation of the tensile direction is found to be strongly dependent on the initial orientation of each grain prior to deformation.     

预应力混凝土连续刚构桥挂篮法施工与监控

结合工程概况,对预应力混凝土连续刚构桥的主要构造设计进行了介绍,阐述了其施工要点,并从结构应力监控、高墩线形监控、上部箱梁线形监控三方面论述了监控测量的主要内容,以供类似工程参考。