Effects of Ti on N distribution and diffusion in FeTiN thin films

We studied the distribution and diffusion of N atoms in FeTiN single-layer and bilayer thin films by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). We found that in as-deposited films N atoms are first absorbed by Ti atoms, the rest being dissolved into FeTi lattices. Ti not only directly absorbs N by chemical bonding, but also decreases the energy of the N atoms that are dissolved into FeTi lattices. The diffusion study of N atoms in single layer and bilayer films showed that although the presence of Ti stabilized the /spl alpha/ phase of FeTi lattices during 200/spl deg/C annealing, the diffusion length of dissolved N in FeTi (Ti/spl les/8 at.%) lattices was still comparable to the diffusion length of N in pure Fe. Thus, the addition of a small amount of Ti in /spl alpha/-Fe lattice can not completely stabilize N atoms in the film, and the induced magnetic anisotropy of the films can still be unstable, although the /spl alpha/ phase of FeTiN is stabilized by the addition of Ti. The distribution of N atoms in bilayer films can be fitted by a simple enthalpy model.     

风机动力型末端在变风量空调系统中的应用

通过对从低温送风技术中发展起来的变风量系统末端--风机动力箱的分析,在实际应用中对比两种型式的该种末端,分析其优缺点,认为这是一种值得在高级办公大楼中优先考虑和推广的系统形式.     

Electroplated hard magnetic material and its application in microelectromechanical systems

We describe the preparation of CoNiMnP-based permanent-magnet material using several sulfate and chloride solutions. We studied eight samples, and all the samples show vertical magnetic anisotropy. Sample8, which was electroplated from a low-concentration chloride solution and under external magnetic field, demonstrates the best magnetic properties with coercivity 2632 Oe, remanence 0.20 T, and maximum magnetic energy 10.185 kJ/m/sup 3/. An array structure can avoid the stress between the electroplated layer and the seed layer. The electroplated Co/sub 0.8/Ni/sub 0.1174/Mn/sub 0.0062/P/sub 0.0762/ permanent magnet has potential for bidirectional actuators in micro-electromechanical systems.     

The hydration characteristics and expansion machanism of expansive cement at low<Emphasis Type="Italic">W/B</Emphasis> ratio

The hydration characteristics and expansion impetus of three kinds of cement paste under free-and confined-curing conditions were investigated, which were respectively mixed with three different kinds of expansive agent at low W/B ratio. The results show that the hydration products of pure cement paste and paste mixed with expansive agent are same, but the amount of hydration products, un-hydrated C₃S and C₂S are obviously different at the same hydration age. At 3 d age, the amount of CH in pure cement paste is less than that of paste mixed with expansive agent, but it is reverse when at 28 d age. The amount of AFt at 3d and 28d age in pure cement paste is less than those of paste mixed with expansive agent. Regardless of under free- or confined-curing condition, the amount of ettringite produced varies little since 3d age. The joint effect of the tumefaction of gel-ettringite due to water absorption and the expansive pressure on the pore caused by the crystalloid ettringite is the cause of the volume expansion of cement paste, and the former effect is much greater than the latter. LU Lin-nu : Born in 1972 Funded by 973 High-tech Project of China (No. 2001CB610704-2) and the Natural Science Foundation of Hubei Province(No. 2002AB075)     

飞轮贮能电池的发展与应用

介绍了飞轮贮能电池作为一种新概念电池所具有的优点：比能量、比功率大，寿命长，无二次污染；概括了飞轮储能电池所涉及的相关技术领域；对国内外飞轮储能技术的发展现状、主要应用领域和发展趋向进行了详细的论述。     

圆锥相贯线的数控切割原理

对圆锥面上的两种相贯线进行了分析，获得了数控切割加工的理论模型，并介绍了为解决这类空间曲线切割加工而研制的数控切割设备，以及该设备在宝山钢铁公司３号高炉制造中的成功使用     

任意形状螺线管磁场的研究

导出了任意形状通电螺线管所产生的磁场在空间的分布情况，并讨论了螺线管在仪器设备中的普遍应用，给出了这类仪器设计中磁场计算的可靠模型     

气相色谱法测定四甘醇样品甲苯和正庚烷含量

建立了测定四甘醇样品中甲苯、正庚烷含量的气相色谱分析法。采用峰面积归一化法进行定量 ,测得甲苯和正庚烷的回收率分别为 98 32 %～ 1 0 2 87%和 97 81 %～ 1 0 2 84% ,相对标准偏差不大于 1 5 0 %和 1 97%。该法快速 ,准确 ,精密度高 ,简单易行 ,具有一定的实用价值。     

Structure, Phonon Vibration, and Spin Correlation of LaBa2Cu3−x Co x O y

Polycrystalline samples LaBa₂Cu_3?xCo _x O _y (0 ≤ x ≤ 1.0) were synthesized by solid state reaction method. The structure, phonon vibration, conduction, and spin correlation were investigated by means of X-ray diffraction, infrared spectra, resistivity, and electron spin resonance. It is found that there are orthorhombic–tetragonal and tetragonal–orthorhombic structural transitions with Co doping, and the conduction behavior changes from metallic to semiconducting. With the increase of Co content, the Cu(1)—O(1) phonon mode around 531 cm^?1 softens, the Cu(2)—O(2) phonon mode around 657 cm^?1 hardens, and the Cu(1)—O(4) mode around 583 cm^?1 is nearly unchanged. The Cu²⁺ spins tend to localize with Co doping. The changes in structure, phonon vibration, and spin correlation with Co doping are analyzed and discussed.     

Properties of Magnetic Nanoparticles about Doped Rare Earth and Its Composites

The magnetic liquid was prepared with ferric salt by inorganic gel technology. The effect of the doped rare earth elements on the properties of magnetic particles was analyzed. The magnetic liquid was composed with clay mineral into magnetic mineral composites. The crystal structure and micro-morphology of the nanoparticles were studied by XRD and TEM. The results show that the crystal structure of the magnetic particles doped 0.5 % of lanthanum is more complete, and the magnetic response capability is higher with doping agent. At the same time, the possibility of the clay mineral magnetic composites as the carrier of target drug was probed.