某些氟化物的升华提纯：II.ZrF4和HfF4的升华提纯

尽管升华方法在除去氧化物方面很有成效，但也必须注意ＺｒＦ４和ＨｆＦ４的水解温度和脱水温度。由于升华方法不能有效地除去象ＦｅＦ３等氟化物杂质。作根据ＦｅＦ６＾３－，ＣｏＦ６＾３－是属于外轨道络合物，它们是不稳定的和容易离解出Ｆｅ＾３＋和Ｃｏ＾３＋，同时ＦｅＺｒ６·６Ｈ２Ｏ也易于离解出Ｆｅ＾２＋，以致使（ＮＨ４）３ＺｒＦ７和（ＮＨ４）３ＨｆＦ７可以用ＤＤＴＣ－ＣＨＣｌ３可以用ＤＤＴＣ－ＣＨＣｌ３，在     

Fe（OH）3中微量金属离子对水热合成α—Fe2O3粒径的影响

本文研究了某些金属离子（Ａｌ＾３＋、Ｍｎ＾２＋、Ｚｎ＾２＋、Ｃｒ＾２＋、Ｎｉ＾２＋、Ｃｏ＾２＋）Ｆｅ（ＯＨ）３凝胶经水热法合成的α－Ｆｅ２Ｏ３微粉颗粒大小的影响。研究结果出现，随着金属离子的浓度在一定范围内（０．０１０－０．０５０ｍｏｌ·Ｌ＾－１）的增加，α－Ｆｅ２Ｏ３颗粒有减小的趋势。其中加入Ｃｏ＾２＋（０．０５０ｍｏｌ·Ｌ＾－１）、Ｍｎ＾２＋（０．１００ｍｏｌ·Ｌ＾－１）可以得到粒径为７５ｎｍ     

软磁材料锰锌铁氧体共沉粉料的研制

本文研究了碳酸盐－氢氧化物法共同沉淀Ｆｅ＾２＋、Ｍｎ＾２＋、Ｚｎ＾２＋时，反应最终ｐＨ值、沉淀温度、加料方式、加料速度及搅拌强度等因素对恒定共沉粉Ｆｅ２Ｏ３、ＭｎＯ及ＺｎＯｍｏｌ％组成、粒度和颗粒形状的影响，并进一步考查了共沉粉组成与软磁材料性能的关系。在研究基础上确定生产高频低功耗锰锌铁氧体材料Ｈ７２４（ＰＣ４０）和高磁导率锰锌铁氧体材料Ｈ５Ｃ２（μｉ＝１００００±３０％）共沉粉合成的最宜条件。     

O＋HO2反应碰撞的理论研究

使用多体项展式分析势能函数，研究了Ｏ＋ＨＯ２反应碰撞的经典轨迹，指出存在二个反应通道，即（１）Ｏ＋ＨＯ２→ＯＨ＋Ｏ２和（２）Ｏ＋ＨＯ２→ＨＯ２＋Ｏ。在室温下，求得反应（１）的近似速度常数为（４．１±０．０６）×１０＾－１１ｃｍ＾３·ｍｏｌｃｃｕｌｅ＾－１·Ｓ＾－１，与实验值（５．４±０．９）×１０＾１１符合甚好；反应（２）的速度常数为５．４×１０＾－１３。对反应（１），总能量的７２．５％分配于产物     

液膜分离富集和测定锤液中的微量铅

用二环己基－１８－王冠－６（ＤＣ－１８－Ｃ－６）、表面活性剂ＳＰＡＮ８０、中性油ＳＩＯＯＮ－１和溶剂三氯甲烷乳状液膜体系，研究了Ｐｂ＾２＋的迁移行为。在适宜条件下，８ｍｉｎ内Ｐｂ＾２＋的迁移率达９９．４％以上，相同条件下，许多金属离子（如Ｎｉ＾２＋、Ｌｉ＾＋、Ｋ＾＋、Ｎａ＾＋、Ｃａ＾２＋、Ｍｇ＾２＋、Ｓｒ＾２＋、Ｂａ＾２＋、Ｆｅ＾３＋、ＡＬ＾３＋、Ｃｕ＾２＋、Ｚｎ＾２＋和Ｃｏ＾２＋等）均不被迁移，     

液膜分离富集金及其微量测定

在协同流体载体（ＴＯＡ和ＰＭＢＰ）、表面活性剂（ＳＰＡＮ８０）、膜增强剂（液体石蜡）、溶剂（煤油）和内相（ＴＵ－ＨＣｌ溶液）乳状液膜体系中，在迁移条件下，１５ｍｉｎ内Ａｕ迁移率达９９．５％以上，而许多常见的离子则不能通过液膜迁移，只有Ａｕ才能从含有ΣＲＥ＾３＋、Ａｇ＾＋、Ｐｄ＾２＋、Ｐｔ４＾＋、Ｒｈ＾３＋、Ｃｕ＾２＋、Ｆｅ＾３＋、Ａｌ＾３＋、Ｐｂ２＾＋、Ｚｎ＾２＋、Ｎｉ＾２＋、Ｍｏ＾６＋、Ｗ＾６＋     

掺铋钇铁石榴石光吸收谱的理论计算

利用ＤＶ－Ｘα方法分别计算了Ｆｅ＾３＋Ｏ＾２－６和Ｆｅ＾３＋Ｏ＾２－４原子族的能态密度和能级，在能级图的基础上，给出了０．５－０．９μｍ（１．６ｅｒ－２．３ｅｖ）范围内Ｂｉ－ＹＩＧ与吸收有关的跃迁能级，振子强度和跃迁线宽，并计算了相应的吸收谱，理论计算与实验结果符合较好。     

P204与C5—7羟肟酸液膜体系自湿法冶锌系统中同步迁移分别回收镓 …

提出了乳状液膜体系自湿法冶锌系统中经一级同时分离镓和锗的新方法,建立了用Ｐ２０４和Ｃ５－７羟肟酸协同载体,ｐＨ＝３．２的ＮＨ４Ｆ溶液为内水相试剂,使Ｇｅ＾４＋以溶液状态而Ｇａ＾３＋则以Ｇａ（ＯＨ）３沉淀同步迁移进入内水相并分别回收的液膜体系,研究了影响Ｇａ＾３＋、Ｇｅ＾４＋迁移的各种因素,经正交实验确定了分离镓和锗的最佳液膜组成及操作条件,并用加入铁粉法除去了杂质Ｆｅ＾３＋和Ｃｕ＾２＋对Ｇａ＾３＋     

Zn-Ti取代的BaFe12O19铁氧体

采用标准陶瓷工艺,并进行湿压磁场成型和氧气氛烧结制备了高取向度、低介电损耗的各向异性Ｂａ（ＺｎＴｉ）ｘＦｅ１２－２ｘＯ１９多晶六角铁氧体,随着ｘ值增大,磁化强度减小,居里温度下降,磁晶各向异性常数减小。结果可以通过假设Ｚｎ＾２＋取代了四面体４ｆ１次点阵位和六面体２ｂ次点阵位上的ＦｅＴ＾３＋;Ｔｉ＾４＋取代了自旋向上的八面体１２ｋ,２ａ次点阵位上的Ｆｅ６３＋来解释。     

WO3中的掺杂及其气敏特性

在ＷＯ３微粉料中掺入１ｗｔ％的不同金属氧化物或金属盐，使ＷＯ３的气敏性能明显变化，掺入Ｔｈ＾＝４，Ｃｄ＾＋４，Ｌｉ＾＋１，Ａｇ＾＋１等可提高对Ｈ２Ｓ的灵敏度，掺入Ｒ＾＋３，Ｔｈ＾＋４，Ｃｅ＾＋４等可增加对乙醇等气体的灵敏性，而对Ｈ２，ＣＯ，ＣＨ４，Ｃ４Ｈ１０等不敏感，而且具有良好的响应恢复特性。     

Zn_xFe_（3－x）O_4的制备及性能

采用合适添加剂在碱性溶液中制备了ＦｅＺｎ铁氧体，研究了其形成机理及磁性能．提出ＦｅＺｎ铁氧体的形成机理为：     

The influence of Cu2+ substitution on the magnetic properties of Fe-Zn and Ni-Zn ferrites

The influence of a Jahn-Teller ion on magnetization,g-values and linewidth in Zn _x Fe_3?x O₄ and Ni_1?x Zn _x Fe₂O₄ spinel ferrites has been investigated by introducing small quantities of Cu²⁺ ions. The magnetization of Cu substitution in both the systems but the curie temperature is affected only in FeZn ferrites. The lattice constant in NiZn is significantly reduced while in FeZn there is only a slight increase. The change ing _eff on copper substitution,_Δ g _eff, is very different in the two systems. In NiZn,_Δ g _eff has a uniform value, ～ 0·2, for all values ofx while in FeZn it has a peak atx=0·3 and vanishes atx=0 andx?0·5. The ferromagnetic linewidth_ΔH does not change significantly on copper substitution in both the systems. An explanation based on the perturbation produced due to the local lattice distortion by the Jahn-Teller mechanism explains the observed results satisfactorily.     

高能球磨法制备Mn-Zn铁氧体材料的研究

以Fe2O3、Mn3O4和ZnO为原料,采用高能球磨法成功制备了Mn-Zn铁氧体,并利用XRD、SEM以及VSM等测试技术对样品进行了表征.研究了预烧温度对铁氧体相的形成过程以及烧结铁氧体材料的显微结构和磁性能的影响.结果表明,随着预烧温度的升高,预烧粉体的颗粒尺寸逐渐增大,起始磁导率和饱和磁化强度均呈现先增大后减小的趋势.适宜的预烧温度为850℃,高于或低于此温度,烧结铁氧体材料的显微结构和磁性能都会恶化.     

Phase Formation during Self-Propagating High-Temperature Synthesis of Ferrites

Phase formation during self-propagating high-temperature synthesis of ferrites was studied. The sequence of phase changes was established, and the intermediate phases were identified. The structure and properties of the synthesized ferrites were investigated.     

Mg—Cu—Zn铁氧体材料的低温烧结及其在片式电感上的应用研究

采用固相反应法制备低温烧结的Mg-Cu-Zn铁氧体（Mg0.68-xCuxZn0.32O）（Fe2O3）0.96（其中x在0.12~0.28变化）,通过XRD对不同CuO含量的Mg-Cu-Zn铁氧体的成相进行了分析,研究了CuO含量及预烧温度对材料性能的影响。在此基础上,利用LTCC技术制作Mg-Cu-Zn铁氧体片式电感,结果显示,低温烧结的Mg-Cu-Zn铁氧体有望成为制备叠层片式电感器的基体材料。     

Mössbauer Studies in the Mechanochemistry of Spinel Ferrites

Mössbauer spectroscopy can provide information on a large variety of mechanochemical processes in solids. In this overview, selected examples are presented of Mössbauer studies of homogeneous and heterogeneous mechanochemical reactions in spinel ferrites. Several interesting features are involved in the work, e.g., mechanically induced cation redistributions, changes of nearest-neighbor configurations, superparamagnetic relaxation, spin-canting effects, as well as formation and redox reactions. The considerable literature on mechanically treated spinel ferrites is reviewed. Despite numerous efforts, the understanding of the nonequilibrium mechanochemical processes in spinel ferrites is considered to be far from complete.     

缺铁YCaZrVIG铁氧体的电磁性能

用传统氧化物法制备了缺铁组分为Y2.3Ca0.7Zr0.3V0.2Fe4.5-δO12（缺铁量δ=0.05）的石榴石铁氧体（YCaZrVIG）,用XRD、SEM对样品进行物相和微结构表征。研究了烧结温度对YCaZrVIG铁氧体物相组成、烧结性能、微观结构及电磁性能的影响。结果表明,烧结后的YCaZrVIG铁氧体为单相的...     

Bulk magnetic properties of Co-Zn ferrites prepared by the co-precipitation method

The alternating current (a.c.) susceptibility versus temperature and magnetization measurements are reported for the disordered spinel ferrite system Zn _x Co_1-x Fe₂ O₄ prepared by a wet chemical method before and after high temperature annealing. The low field a.c. susceptibility measurements indicate that the low temperature synthesis of wet prepared Co-Zn ferrites aids the formation of spin-clusters and thereby increases the magnetic inhomogeneity. The X-ray analysis shows that the samples are single phase spinels and the variation of lattice constant with zinc concentration deviates from Vegard's law [1]. The high temperature annealing changes the wet prepared ferrites into the ordered magnetic structure of the ceramic ferrites.     

Synthesis, characterization and magnetic properties of Zn substituted Li-Ni nano ferrites

Nanosized Li-Ni-Zn ferrites with general chemical formula Li0.5 Ni(0.75-x/2) Zn(x/2) Fe2O4 (0 < x < 1) were synthesized from a simple polymer matrix based precursor solution. The solution was composed of metal nitrates, polymer (PVA) and disaccharide (sucrose). Thermolysis/flame pyrolysis of the precursor mass in an external temperature resulted in the oxide phase formation. X-ray diffraction studies confirm the formation of single phase ferrites. The microstructural analysis was carried out by scanning electron microscopy (SEM). The average grain diameter was estimated by the Scherrer method and grain diameter is found to vary from 16 nm to 33 nm. The saturation magnetization was studied as a function of composition.     

锰锌、镍锌铁氧体的研究现状及最新进展

对常用的锰锌、镍锌软磁铁氧体材料的应用及其性能进行了介绍,着重从配方要求、添加剂的作用等方面综合介绍了国内外的研究情况及最新进展,指出了今后软磁铁氧体研究的主要方向及所要达到的性能要求.研究表明,配方是决定铁氧体材料性能好坏的决定性因素,加入添加剂是改善铁氧体材料性能的有效方法之一,烧结工艺是制备高性能铁氧体的关键.今后软磁铁氧体发展的重点是高频低功耗、高磁导率材料和片式化的表面贴装元件,还应开展纳米软磁铁氧体的研究.