| 1. | Block a sequence of bits of fixed length
定长的块a位序列。 |
| 2. | 4 . magnetism study on we presented a detailed study of dy - doping effect on magnetism
第四章研究了a位第二类稀土元素替代对锰氧化物磁性的影响。 |
| 3. | Moreover , the diffraction peak shifts toward high angle as sr content increases . it is ascribed to the substitution of la3 + by sr2 + in lscf increases the average radius of a ions and causes a charge imbalance
且随着sr含量的增加，衍射峰值向高角度方向稍有偏移，这是由于低价sr ~ _ ( 2 + )取代高价la ~ ( 3 + )增加了a位离子的平均半径，同时引起电荷不平衡。 |
| 4. | The investigation of structure by x - ray diffraction shows that crystal parameters changes clearly when percenting ca and la into pbtio _ 3 , it was caused by the ca ion and la ion replaced the pb ion of a position in perovskite compound , that bring lattice mismatch and asymmetrical replace
在pbtio _ 3中掺入la和ca可以有效改变薄膜的晶格常数,这是因为在abo _ 3型化合物中,钙离子、镧离子取代了a位的铅离子,造成晶格失配和不对称取代。 |
| 5. | However few existed in nature . many of the multiferroelectric magnetoelectric material have been synthesized by two phases for the purpose , and many of the research have always been concentrated on the substitution between the a - site cation ln and other metallic ions effect on the properties
这些材料很少存在于自然界中，为了达到这种效果，大多可以利用两相混合烧结获得，且主要就钙钛矿结构相中a位离子ln与其它金属离子的取代及对性能影响进行研究。 |
| 6. | The substitution of a - site cation ln can induce significant effect on the magnetization and polarization , nevertheless b - site cation can induce more effect on the polarization of perovskite structure . as a result , the doping of titanate which had typical high dielectric behavior would have significant effect on the research and development of novel multiferroelectric magnetoelectric material
A位离子ln的取代可以对材料的磁化性能和极化性能产生影响，然而由于b位离子对钙钛矿结构的极化可能产生更大的作用，因而具有典型高介电行为的含ti钙钛矿结构的引入将可能对新型复铁电性的磁电子材料的开发研究产生很大的影响并具有非常重要的科学意义。 |
| 7. | The future work will be concentrated as following : ( 1 ) the mechanism of the effect of doping in a site on 2pr should be clarified by the research on the rule of 2pr of sbti doped by the lanthanide serials having different ions radii ; ( 2 ) the properties bit - sbti doped in the b site should be studied ; ( 3 ) the thin films of these materials should be prepared and their properties should be studied
今后的工作要点主要为: ( l )用la系其它元素对sb五掺杂，通过改变离子半径，研究2pr的规律，验证我们提出的a位掺杂对材料zpr影响机理; ( 2 ) b位掺杂对brr - sb五的性能影响研究; ( 3 )这些材料的薄膜制备及性能测试。 |
| 8. | The difference between the magnetic moments for the samples with respective doping level can be ascribed to the variation of the competition between thermal effect and the magnetic coupling . based on the spin orientation rotation of dy sublattice as well as the antiferomagnetic coupling between dy sublattice and mn sublattice , we successfully elucidate the changes of magnetic structure in perovskite compounds s . electron spin resonance ( esr ) study on perovskite compounds on the basis of chapter 4 , we give further study on micromagneticism of dy - doping perovskite compounds la0 . 67 - xdyxsr0 . 33mno3
其中第一节简单回顾了早期对a位双稀土元素元素掺杂钙钛矿化合物的研究，早期研究较多的是替代元素的离子半径变化上，由于替代离子半径的改变，使a位平均半径变ylll化，致使公差因子改变，使mn o长、键角变化，晶格效应的作用使化合物的磁性、电性、 cmr效应发生改变。 |
| 9. | According to the sample prepared by hydrothermal method , the doping cations can enter the spinel lattice . rare earth cations mostly occupy position b because of their big radius . cerium are oxidized to ce4 + , whose radius is relatively small , and ce4 + mostly occupies position a . as a whole , the coercivity of cobalt ferrite doped with rare earth element is bigger than that of pure cobalt ferrite
结果表明，对水热法制备的铁氧体粒子，杂质离子能够进入其尖晶石晶格中，并因稀土离子的半径较大，而绝大部分占据尖晶石的b位，铈元素因被氧化成为四价离子，离子半径相对较小，而主要占据a位。 |
| 10. | This viewpoint is concided with the 2pr of sr2bi4ti5o18 ferroelectrics doped by la . the curie temperatures of sblt and blt - sblt decrease with the increase of la content . for sblt , when la content excesses 0 . 75 , the samples exhibit typical characteristics of relaxor type ferroelectrics . blt - sblt with 1 . 50 la exhibits characteristics of relaxor type ferroelectrics as well
Sbti和bit - sbti经a位掺杂后，居里温度( t _ c )都随掺杂量的增加而降低，在掺杂量分别为0 . 75以上和1 . 50时，二者都出现了弛豫铁电体的典型特征。 |
