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921.
磁选柱在本溪钢铁集团选矿厂的应用   总被引:2,自引:1,他引:1  
在本溪钢铁公司提铁降硅工程中,磁选柱成功应用于本钢南芬和歪头山两大选矿厂,实现了最终精矿品位68.50%以上,二氧化硅小于4.50%的指标。实践证明磁选柱能够有效地剔除磁团聚中夹杂的连生体和单体脉石,是“提铁降硅”工程首选的精选磁铁矿获得高品位精矿的设备。  相似文献   
922.
准分子激光器中磁开关的实验研究   总被引:3,自引:0,他引:3  
根据准分子激光放电要求,分析了准分子激光器中磁脉冲压缩开关的工作过程,并给出了研制的高效率的磁开关的实验结果。  相似文献   
923.
Water status of cooked white salted noodles evaluated by MRI   总被引:5,自引:0,他引:5  
Transverse relaxation time (T2)-weighted images and T2 maps of white salted noodles (WSN) were investigated by magnetic resonance imaging technique. T2-weighted images and T2 maps clearly showed the differences in water status between noodles. The migration of moisture from surface regions to central regions of boiled WSN at different migration rates were investigated during storage. The distribution of T2 values changed differently depending on the cooking and storage times. The small differences in T2 values between surface region and central region of noodles cooked for 5 and 15 min were attributed to the limited water absorption during short cooking time, which resulted in high firmness. The changes in starch granules morphology observed under scanning electron microscope and the increase of noodle firmness measured by texture analyzer were significantly affected by the water status in noodles. The water status can be controlled by the cooking time.  相似文献   
924.
对钇钕铁石榴石单晶薄膜材料进行了大量的性能研究,发现了过冷度与错配度、光损耗的关系,并提出了改善其磁光性能的可行途径。同时作出了XPS能谱图,比较氧化前后能谱图的差别,对实验结果给出了明晰的解释。  相似文献   
925.
针对玻璃、冶金、铸造、陶瓷等行业中普遍使用的粉料中含铁杂质问题,设计了一种除铁机。该机利用双电机驱动自同步惯性振动过筛,电磁除铁,生产效率高、操作简便。基本参数为振幅λ=1.3×10^-3m,抛掷指数D=2.75,选用20目筛处理颗粒尺寸为d=0.07~0.05mm的粒料时,生产率Q=600kg/h。为电磁系统及振动系统、结构设计提供了理论依据。  相似文献   
926.
本文阐述了微型机电系统领域中微泵的几种常见的致动方式及其特点。根据硅微泵的结构特点,制作出用于微型泵的电磁致动器,并对该电磁致动器进行了分析与振动测试。  相似文献   
927.
Sen-lin Wang 《Thin solid films》2007,515(23):8419-8423
The Ni-Co-B alloy was electrolessly deposited from the bath using potassium borohydride as a reducing agent and ethylenediamine as a stabilizer. The effects of the plating conditions on the plating rate and the composition of the deposit were studied to improve the stability of the plating bath and to control the composition of the Ni-Co-B deposit. The crystallization behavior of the deposit was investigated by X-ray diffraction. The results show that the structure of the as-plated deposit is amorphous, and the deposit was crystallized into cubic Ni3B and Ni-Co phases at 350 °C. The effect of heat treatment on the magnetic performances of the deposit was studied by vibrating sample magnetometer. The saturation magnetization and the residual magnetization of the coating go up with the increase of heat treatment temperature from 50 °C to 600 °C. The deposit heat-treated at 600 °C is found to be suitable as soft magnetic materials.  相似文献   
928.
Magnetically induced texture development in zinc alloy sheet   总被引:5,自引:0,他引:5  
Highly textured Zn–1.1%Al sheet was annealed in a direct-current magnetic field of 25.5 MA/m. Depending on the orientation to the field the texture components strengthened, retained their original intensity or disappeared. The results obtained are interpreted in terms of magnetically induced selective grain growth.  相似文献   
929.
Magnetic tunnel junctions (MTJ), with the tunnel barrier plasma oxidized in two steps, were fabricated in order to obtain structurally uniform AlOx insulator. The doubly oxidized junctions exhibited the magnetoresistance (MR) ratio of 27-31% without showing any noticeable drop in the MR ratio even after oxidation time was extended well beyond the optimal oxidation time for the normal junctions. Transmission electron microscopy of the junctions confirmed that the AlOx thickness was thinner for the doubly oxidized junctions compared to the singly oxidized MTJ. X-ray photoelectron spectroscopy of the doubly oxidized junction also strongly suggested that the initial oxide layer prevents the over-oxidation of the bottom electrode. The AlOx tunnel barrier oxidized in two steps improved the junction performance and widened the processing window.  相似文献   
930.
This paper focuses on the development of a magnetic moment method of calculating vector field quantities for a highly permeable ferrite cored eddy current probe. Basis functions are used in this method to replace the scattered field caused by the probe core in accordance with the surface equivalence theorem. These functions are further developed and tested for accuracy and convergence. An efficient material profile equation, independent of probe coil and basis function properties, is also designed and verified. Collocation point selection and optimisation is finally undertaken leading to the accurate determination of probe source coil impedance. The accuracy of calculation is verified using an industry standard finite element solver.  相似文献   
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