应变纤锌矿ZnO/MgxZn1-xO量子点中离子施主束缚激子的光学性质

Within the framework of the effective-mass approximation and the dipole approximation, considering the three-dimensional confinement of the electron and hole and the strong built-in electric field(BEF) in strained wurtzite Zn O/Mg0:25Zn0:75O quantum dots(QDs), the optical properties of ionized donor-bound excitons(D+, X)are investigated theoretically using a variational method. The computations are performed in the case of finite band offset. Numerical results indicate that the optical properties of(D+, X) complexes sensitively depend on the donor position, the QD size and the BEF. The binding energy of(D+, X) complexes is larger when the donor is located in the vicinity of the left interface of the QDs, and it decreases with increasing QD size. The oscillator strength reduces with an increase in the dot height and increases with an increase in the dot radius. Furthermore, when the QD size decreases, the absorption peak intensity shows a marked increment, and the absorption coefficient peak has a blueshift. The strong BEF causes a redshift of the absorption coefficient peak and causes the absorption peak intensity to decrease remarkably. The physical reasons for these relationships have been analyzed in depth.     

水口水电站主轴密封结构分析

本文简要介绍了福建水口水力发电厂主轴密封结构的演变，运行情况及部分改进措施。     

我国乳品加工技术创新体系发展方向的研究

从乳品加工产前、产中、产后三个方面，论述了我国乳品工业在技术方向应优先发展领域和发展方向。     

Correlated electron-hole transitions in wurtzite GaN quantum dots:the effects of strain and hydrostatic pressure

Within the effective-mass and finite-height potential barrier approximation,a theoretical study of the effects of strain and hydrostatic pressure on the exciton emission wavelength and electron-hole recombination rate in wurtzite cylindrical GaN/Al_xGa_1-xN quantum dots（QDs） is performed using a variational approach.Numerical results show that the emission wavelength with strain effect is higher than that without strain effect when the QD height is large（> 3.8 nm）,but the status is opposite when the QD height is small（< 3.8 nm）.The height of GaN QDs must be less than 5.5 nm for an efficient electron-hole recombination process due to the strain effect.The emission wavelength decreases linearly and the electron-hole recombination rate increases almost linearly with applied hydrostatic pressure.The hydrostatic pressure has a remarkable influence on the emission wavelength for large QDs,and has a significant influence on the electron-hole recombination rate for small QDs.Furthermore,the present numerical outcomes are in qualitative agreement with previous experimental findings under zero pressure.     

GB50500--2008在实际工程招标的应用

结合实际工程,探讨了施行GB50500--2008《建设工程工程量清单计价规范》之后,采用工程量清单计价如何编制工程量清单和招标控制价、投标报价、合同价款约定以及工程价款调整等内容。     

铁钴纳米合金的制备及表征

Fe-Co合金是重要的金属软磁材料,由于具有高饱和磁感应强度、低矫顽力、高磁导率和低磁各向异性常数等独特的软磁材料性能而倍受关注。本实验以水合肼为还原剂,PVP为分散剂,采用液相还原法制备出纳米Fe-Co合金,并利用X射线衍射仪(XRD)、扫描电镜(SEM)、差示扫描量仪(DSC)对样品进行了表征。研究结果表明:制得的样品为非晶态无定形;颗粒呈球形,平均粒径为57nm;Fe-Co合金的抗氧化能力较强,在常温下不易被氧化。最后对Fe-Co纳米金属材料的发展趋势进行了展望,同时指出了Fe-Co纳米金属材料制备方法研究中存在的问题。     

鱼油微胶囊技术的研究

采用喷雾干燥法对鱼油进行微胶囊化 ,并对产品进行质量评定。结果表明 :壁材阿拉伯胶、糊精、玉米糖浆的最佳配比为 3∶ 3∶ 4 ,芯材占壁材的添加量为 30 % ,乳化温度为 5 0～ 60℃ ,乳化剂添加量为 0 8% ,喷雾干燥的进风温度为 2 0 0℃ ,制得的产品质量较高 ,产品水分含量为 2 30 % ,溶解度为 94 7% ,颗粒直径 38μm,且感官质量较高。     

北方浓香型原酒与窖泥质量关系的探究

通过对窖泥理化指标主要是窖泥功能菌的比较,分别判断对原酒中总酸、总酯、总醛及总醇含量的影响。得出窖泥质量的好坏对原酒中的总酸总酯有明显的影响,窖泥质量好时两者含量较高。与原酒中总醛和总醇的含量没有明显的关系。     

豆渣膳食纤维提取工艺预处理条件的研究

本文介绍的是以一种新的预处理手段一挤压技术,处理豆渣原料,从而提高可溶性膳食纤维(SDF)得率的制备工艺。通过单因素及L9(34)正交试验得出用豆渣提取膳食纤维(DF)最佳工艺条件为:氢氧化钠用量5%、胰蛋白酶用量0.13%、碱浸泡时间60min、碱浸泡温度80℃,产品中小可溶性膳食纤维(IDF)纯度为81.07%,可溶性膳食纤维(SDF)得率6.94%。由于近年来人们对可溶性膳食纤维(SDF)的生理功能越来越认可并关注,且相关报道层出不尽,并已知挤压技术的应用可提高膳食纤维中的可溶性膳食纤维(SDF)含量,其主要依据是纤维素在高温、高压、高剪切力和摩擦力的作用下大部分半纤维素和少数纤维素降解成可溶性膳食纤维(SDF)。因此,在豆渣制取膳食纤维(DF)的预处理过程中加入挤压工艺可显著提高其可溶性膳食纤维(SDF)的得率。通过L9(33)正交试验得出单螺杆挤压最佳工艺条件为:物料水分25%、挤压温度180℃、螺杆转速175r/min。在此工艺条件下,可溶性膳食纤维(SDF)的得率由6.94%提高到19.45%。     

大豆低聚糖在酸奶中的应用

采用单因素试验设计研究国产大豆低聚糖在酸奶中的应用 ,得出在酸奶中大豆低聚糖的添加量在2 %～2 5 %之间时 ,不影响酸奶的质量 ,并具有保健意义 ,酸奶在保藏七天时大豆低聚糖损失率仅为9 8%