电机定子铁芯铁损测试中假热点的判断及消除

电机定子铁芯测试是确定电机定子铁损损耗的大小以及查找电机定子铁芯缺陷的重要试验。确定电机定子铁损损耗除了利用测量试验的电流、电压来计算外,另一种重要的手段就是通过测量电机定子铁芯在试验过程中的温升来     

三醋酸纤维素膜中铁含量测试方法

应用氧化亚氮—乙炔火焰原子吸收法测定航天空间电源材料三醋酸纤维素膜中的含铁量。并对测试条件、干扰因素进行了综合考虑。该方法具有很好的灵敏度、精确度、化学干扰少、测试条件选择性大、重现性好等优点。相对标准偏差ＲＳＤ＜１０％（ｎ＝１０），标准加入回收率均在９７０％～１０２０％（ｎ＝４）范围内。完全适用于在三醋酸纤维素膜中含铁量的控制和样品系统分析。     

铁证如山!——有关飞碟的古代证言

UFO，究竟是外星人派遣来的探测嚣——飞堞．还是地球大气层中的某种天文、气象或生物现象？这是人们争论了丰个多世纪的问题．由于爱文明程度的限制．故目前人们还认识不到、解释不了这其中的奥秘。有些人不但自以为高明地把UFO斥之为“伪科学”．而且从根本上否认UFO现象的客观存在，这完全违背了自然科学赶展豌的一个根本方法原则：观察入手．实事求是，这也是某些大学者的悲表!     

Synthesis of Iron-containing Carbon Microparticles from Deoiled Asphalt and Ferrocene

The deoiled asphalt as the carbon source and the ferrocene as the metal source and the catalyst precursor were chosen to synthesize iron-containing carbon microparticles through co-carbonization at the temperature of about 450℃ for 3 h. The resulting products were treated at 2 000 ℃ for 2 h. All samples were examined by high resolution transmission electron microscopy （HRTEM） and X-ray diffraction （XRD）. The results show that the iron particles in the heat-treated material are completely coated by carbon. In addition to the fully filled carbon microparticles as well as hollow carbon ones, also form carbon fibers with hollow centers. The formation mechanism of the as-prepared products was discussed briefly.     

Change of Electronic Structure and Magnetic Properties with MgO and Fe Thicknesses in Fe/MgO/Fe Magnetic Tunnel Junction

The effects of the thickness of MgO and Fe on the electronic structure and magnetic properties of Fe/MgO/Fe magnetic tunnel junction was studied using the first principle method. Two series of models with MgO of different thicknesses： Fe（3）MgO（t）Fe（3） （t-=1,3,5,7） and with Fe of varied thicknesses： Fe（t）MgO（3）Fe（t） （t=3,4,5,6,7） were established. Calculated results show that in all the models the magnetic moment of Fe increases at the Fe/MgO interface and surface as compared with that of the inner layers. The mag- netic moment of each Fe layer was found to be independent of MgO thicknesses, while the spin-polarization of Fe layer at the interface shows a slight change in function of the MgO thicknesses. The tunneling magnetoresistance （TMR） ratio estimated by the Julliere model has the same change tendency as the spin-polarization has, and the largest value is obtained at the MgO thickness of 5 atomic layers. When the Fe thickness increases, the spin-polarization of interface Fe layer follows up an increase with a decrease. The highest TMR value is achieved when the Fe thickness is of 4 atomic layers.     

以色列计划部署第4套铁穹火箭弹防御系统

日前，以色列宣布已作好在其北部港口城市海法部署第4套由拉法尔先进防务系统公司研发的铁穹火箭弹防御系统的准备，以保护其炼油厂及氨水池。     

铁（Ⅲ）—苯芴酮—Tritonx—100体系测定铬若美中的铁

本文研究了铁 (Ⅲ ) -苯芴酮—Tritonx -1 0 0体系测定铬若美中的微量铁。铁与苯芴酮的二元配合物的摩尔吸光系数值可达 6 4× 1 0 4 ·L·mol- 1·cm- 1,加入表面活性剂Tritonx -1 0 0后 ,铁与苯芴酮、Tritonx -1 0 0生成三元配合物 ,摩尔吸光系数值提高到 2 4× 1 0 5·L·mol- 1·cm- 1,Fe含量在 1 4 5～ 2 8μg/2 0ml范围内服从耳定律 ,回收率 97%～ 99% ,反应选择性好 ,用拟定的方法测定铬若美 (铬和镍合金 )中的微量铁 ,测试结果令人满意