预处理玉米秸秆发酵生产燃料酒精的研究

本文利用正交试验对玉米秸秆发酵生产燃料酒精的条件进行了摇瓶试验。试验发现,采用管囊酵母SQY-001与 酿酒酵母SQY-002混合菌种发酵生产酒精的最适条件为发酵温度36℃,发酵周期为72h,转速为80～100r/min,纤维素酶用量为 40IU/g底物,管囊酵母与酿酒酵母的接种比例为2:1,并在此条件下得到酒精产率为0.148g/g。     

碳纳米管沉积铂和钌对PEMFC抗CO中毒能力的影响

通过催化裂解法制备了碳纳米管,对其进行氧化处理后,在其表面沉积了分布均匀、尺寸呈纳米级的铂和铂/钌颗粒.实验结果表明,当采用碳纳米管沉积铂为催化剂时,质子交换膜燃料电池的催化剂铂很容易受CO的毒化而失去活性,从而使电池的电压随电流密度的降低而迅速降低;当采用碳纳米管沉积铂/钌为催化剂时,钌能够使铂表面吸附的CO被氧化为CO₂,增加催化剂对CO的抵抗能力,使燃料电池的性能提高.     

利用地层微电阻率扫描图像识别岩性

地层微电阻率扫描测井（FMI）具有很高的采样密度和纵向分辨率,所得图像可以直观地显示井壁地层的微细变化,对细成地层的岩石类型,岩石结构,深积构造,裂缝等特征可以进行精细描述,本文在岩心观测的基础上,对胜利油田,长庆油田十几口井的地层剖面微电阻率扫描图象进行了精细解释,建立了地层 面微电阻率扫描图像进行了精细解释,建立了碎屑岩,碳酸盐岩和岩浆岩3类地层所属各种岩性在FMI图像上的识别模式。     

MOS器件的质子总剂量效应

介绍了几种加固和非加固 MOS电路的质子辐照总剂量效应实验 ,质子束的能量为 9、 7、 5、 2 Me V.实验结果表明 ,在相同的吸收剂量下 ,MOS器件累积电离辐射损伤与质子能量成正比 .还给出了栅极偏压对器件质子辐射损伤的影响 ,结果认为 ,对于 NMOSFET,不论是加固器件 ,还是非加固器件 ,在 +5 V的栅压偏置下 ,器件的辐射损伤比 0 V栅压下的损伤严重 ,对于加固器件 ,辐射感生界面态的密度也较高 ;而加固型 PMOSFET,在 0 V的栅压下 ,辐射损伤比 - 5 V下严重 ,且界面态的密度高     

Enhancement of the dielectric properties of Pb(La,Ti)O3 thin films fabricated by pulsed laser deposition

PLT thin films with a thickness of 600 nm were grown by pulsed laser deposition (PLD) using different laser wavelengths of 355, 532 and 1064 nm, respectively. We have systematically investigated the variation of grain sizes depending on the process condition. A two-step process to grow (Pb_0.72La_0.28)Ti_0.93O₃ (PLT) films was adopted and verified to be useful to enlarge the grain size of the film and to enhance leakage current characteristics. Structural and electrical properties including dielectric constant, ferroelectric characteristics, and leakage current of PLT thin films were shown to be strongly influenced by grain size.     

Thin film TiO2 on nickel(110): an STM study

Titanium oxide films grown on the surface of a Ni(110) single crystal have been investigated using STM, LEED and AES for Ti coverages ranging from 1 to 10 ml [1 ml of Ti is defined here as equivalent to the number of top layer Ni atoms of Ni(110)]. The oxide overlayers were prepared by vapour phase deposition of Ti followed by oxidation in 1×10⁻⁷ mbar O₂ at 800 K. Oxidation of Ti coverages between 1 and 10 ML results in STM images indicating the presence of two terminations coexisting on the surface. One termination consists of islands of epitaxial rutile TiO₂(110), the second having cell parameters of 2.98±0.1×3.15±0.2 Å. The latter unit cell is consistent with TiO(001) (2.99×2.99 Ų). On oxidation of higher Ti coverages (10 ml), only epitaxial rutile TiO₂(110) islands are observed.     

Growth of copper and vanadium on a thin Al2O3-film on Ni3Al(111)

The growth of different metals on thin Al₂O₃-films on Ni₃Al(111) was investigated using scanning tunneling microscopy (STM). These thin alumna films are well ordered showing two superstructures, which appear in the STM images at different bias voltages. These superstructures, with periodicities of 2.6 and 4.5 nm, respectively, are shown here to govern the nucleation of the deposited metals. Copper clusters grow on these nucleation centers only at room temperature. Higher temperatures lead to an increase of the cluster size and the loss of order. In turn, vanadium forms ordered cluster arrays at room and higher temperature. Due to the stronger metal–oxide interaction compared to copper vanadium forms smaller clusters at low and high coverages, which do not show any ripening after annealing. Based on these observations, Al₂O₃-films on Ni₃Al(111) prove to be an interesting template for the fabrication of periodic cluster arrays.     

Application of self-tuning fuzzy controller for a Cartesian manipulator on unknown contours

Owing to the relative difficulty in achieving contour tracking on 3D objects, this study presents a novel compliant motion controller by applying the self-tuning fuzzy control to have a Cartesian manipulator implement contour tracking on unknown contours. A data fitting method is also developed to reduce the noise errors of the measurement. Moreover, the radius compensating method is used to correct the measured data. The Cartesian manipulator is tested and calibrated beforehand. Results in this study demonstrate the feasibility of the control strategy proposed herein.     

Detection of cracks in concrete composites using acoustic microscopy

We demonstrate that a scanning acoustic microscope (SAM) operating in the frequency range 100–400 MHz can detect cracks at the aggregate/paste interface and subsurface cracks in aggregates with high sensitivity. A complete interpretation of the obtained results has been made by combining high and low frequency acoustic microscopy, SEM, optical microscopy, and energy dispersive (X-ray) spectroscopy.     

Oil globule microstructure of protein/polysaccharide or protein/protein bilayer emulsions at various pH

The microstructure of oil droplets of bi-layer emulsions was studied as a function of pH (i.e. 7, 5, and 3) using scanning electron microscopy. The bi-layer emulsions consisted of a primary emulsion: 5 wt% soybean oil (SBO) in a 1% protein (nonfat dry milk) aqueous solution. The secondary layer was ι-carrageenan, high- (HMp), low (LMp)-methoxyl pectin, or gelatin. The secondary emulsions consisted of 2.5% SBO, 0.5% protein, and 0.2% polysaccharide or protein. Gelatin secondary emulsions were stable at pH 7 with defined droplets and became unstable at pH 5 and 3. The destabilization mechanisms for these emulsions at pH 5 and 3 were different as observed with the SEM: at pH 5 there is complete aggregation of protein due to their proximity to the isoelectric point; and at pH 3 the droplets are perfectly separated, suggesting that at this pH, when the net charge is positive, the destabilization is mainly due to depletion flocculation. HMp secondary emulsions shift from being stable (individual droplets) at pH 3 to being unstable at pH 7 where an extensive webbing is observed between the droplets at this pH value. The ι-carrageenan secondary emulsions are stable at each pH and the individual droplet microstructure is minimally altered as the pH changes. LMp secondary emulsions shift from being stable at pH 7 with individual droplets observed in the SEM micrographs to being unstable at pH 3 where extensive webbing is observed in the SEM micrographs.