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81.
Yufeng Su Hong Wang Guifu Ding Feng Cui Weiping Zhang Wenyuan Chen 《IEEE transactions on magnetics》2005,41(12):4380-4383
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. 相似文献
82.
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) 相似文献
83.
飞轮贮能电池的发展与应用 总被引:3,自引:0,他引:3
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。 相似文献
84.
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 相似文献
85.
任意形状螺线管磁场的研究 总被引:1,自引:0,他引:1
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 相似文献
86.
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。 相似文献
87.
马钢四铁厂2号高炉开炉实践 总被引:1,自引:0,他引:1
马钢四铁厂2号高炉通过开炉前的认真准备,加强人员培训,选择合适开炉料和送风参数以及送风后尽快降硅、合理调整煤气流等一系列措施,高炉开炉后生产水平快速上升,实现了开炉15天达产,第二个月高炉利用系数达2.238的好成绩。 相似文献
88.
89.
Ruhua Tao Gaojie Xu Biao Liu Zhuan Xu Jingqin Shen Qirong Pu Guansheng Wang Zejun Ding 《Journal of Superconductivity and Novel Magnetism》2004,17(3):469-472
Polycrystalline samples LaBa2Cu3?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. 相似文献
90.
TANG Qingguo Shen Shangyue Wang Lijuan LIANG Jinsheng Ding Yan Meng Junping LI Guosheng WANG Man 《中国稀土学报(英文版)》2004,22(Z3)
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. 相似文献