废雷尼镍催化剂的综合利用

以废雷尼镍催化剂为原料,制备出合格的硫酸镍,硝酸镍和氧化镍。利用化学分析方法测定这种废催化剂含Ｎｉ＾２＋ｏ ６６．０６％,Ｆｅ＾２＋为０．７７９％,Ｃｒ＾３＋为１．４５６％,选用ＮａＣｌＯ作氧化剂将Ｆｅ＾２＋氧化成Ｆｅ＾３＋,再调节溶液的ＰＨ值为５．０－５．６,将Ｆｅ＾３＋和Ｃｒ＾３＋以氢氧化物的沉淀形式过滤除去。滤液加入学硫酸,调节ＰＨ值处于３．５－４．０之间,然后冷却,结晶,离心即得ＮｉＳＯ４     

Sm,Gd共同掺杂的CeO2基电解质性能研究

用Ｓｍ２Ｏ３和Ｇｄ２Ｏ３共同掺杂ＣｅＯ２基电解质组分（ＣｅＯ２）０．９０（Ｓｍ２Ｏ３）０．０５（Ｇｄ２Ｏ３）０．０５）,可以在较低的温度（１４００－１４５０℃）烧结并较高电导率,８００℃时电导率约为７Ｓ．ｍ＾－１。     

Fe2O3—SrO—TeO2系半导体玻璃电导的研究

有准急压冷法制成Ｆｅ２ｏ３－ＳｒＯ－ＴｅＯ２系半导体玻璃并对其直流电导率进行了测定。玻璃形成范围为（以摩尔计）０≤ｆｅ２Ｏ３≤２３％；０≤ＳｒＯ≤１８％；７５％≤ＴｅＯ２〈１００％。通过Ｓｅｅｂｅｃｋ系数的测定确认Ｆｅ２ｏ３－ＳｒＯ－ＴｅＯ２系玻璃为ｎ型半导体玻璃。２００℃的直流是导率为３．７２×１０＾－５－１．８２×１０＾－６Ｓ．ｃｍ＾－１。直流电导率随着Ｆｅ２Ｏ３含量的增加而增加。１６５℃时的     

合成Co2O3—Cr2O3—F32O3—MnO2系高温黑颜料最佳工艺条件的探讨

本文介绍了Ｃｏ２Ｏ３－Ｃｒ２Ｏ３－Ｆｅ２Ｏ３－ＭｎＯ２系高温黑颜料的合成工艺，研究分析了四种氧化物的不同配比、混合及合成温度等工艺过程对颜料呈色的影响，从而确定了含钴量较低呈色纯正的Ｃｏ－Ｃｒ－Ｆｅ－Ｍｎ系高温颜料的最佳工艺条件，并利用过渡金属络合物吸收光谱理论对Ｃｏ、Ｃｒ、Ｆｅ、Ｍｎ四种元素的变价离子使含Ｂdisplay status     

不锈钢黄绿色铬酸盐转化膜的研究

采用铬酸盐溶液在不锈钢表面获得黄绿色化学转化膜。利用Ｘ射线光电子谱分析法及俄歇电子能谱法分析了所得镀层的元素组成，各元素含量及化学状态所得膜层厚度为１２７ｎｍ，主要由Ｃｒ、Ｆｅ、Ｎｉ、Ｏ等元素组成，它们分别以ＣｒＯ３、Ｆｅ２Ｏ３和ＮｉＯ的形成存在，其相对原子百分浓度分别为Ｃｒ２４．０Ｆｅ２．６，Ｎｉ０．５。     

耐硫酸及其盐腐蚀的新型双相不锈钢的研究

针对含Ｈ２ＳＯ４１１０．５ｇ／Ｌ、Ｎａ２ＳＯ４３８７ｇ／Ｌ、ＺｎＳＯ４１４．４ｇ／Ｌ，密度为１．３５ｇ／ｃｍ３，温度为６０℃的介质，设计了泵用不锈钢的金相组织和化学成分。其金相组织确定为奥氏体—铁素体双相不锈钢，化学成分为：Ｃ≤０．４％、Ｓｉ４．０％～５．０％、Ｍｎ≤０．８％、Ｐ，Ｓ≤０．０３％、Ｃｒ１９％～２１％、Ｎｉ１９％～２１％、Ｍｏ２．０％～３．０％、Ｃｕ２．０％～３．０％，其余为Ｆｅ。采用金相显微镜和Ｘ射线衍射的方法观察与分析了钢的金相组织，通过试验测定了耐蚀性能，并与性能优良的９０４和ＣＤ４ＭＣｕ钢进行对比。试验结果表明，经１１００℃固溶处理后的新型双相不锈钢（ＫＳ－５）耐蚀性能明显优于对比合金。     

钡锶铅氧化物陶瓷的结构与热敏性

本文应用共沉淀法制备了Ｂａ１－ｘＳｒｘＰＢ１＋ｙＯ３－δ（Ｘ＝０，０．１，０．３．０．５，０．７，１；ｙ＝０．０．１．０．２，０．３）陶瓷试样。测定了试样的电阻－温度特性。并对样品进行了Ｘ射线衍射分析（ＸＲＤ）和扫描电子显微镜（ＳＥＭ）的观察，以研究Ｓｒ掺杂ＢａＰｂＯ３陶瓷的结构和热敏性。实验结果表明：掺杂钡铅氧化物陶瓷仍是钙钛矿结构。随着Ｘ含量增加（ｙ为定值）陶瓷的ＰＴＣＲ温度升高，但ＰＴＣＲ效应逐渐降低；ｙ＝０时，几乎没有ＰＴＣＲ效应．ｙ＞０．２时，ＰＴＣＲ效应也不明显，而在０＜ｙ≤０．２时，ＰＴＣＲ效应随ｙ值的增加而增大。     

SrFe1.5-xCoxOy混合导体的制备及氧化扩散研究

详细研究了混合离子导体ＳｒＦｅ１．５－ｘＣｏｘＯｙ（ｘ＝０．０－０．５）的相组成和氧化学扩散性质。Ｘ射线衍射和扫描电镜分析表明：该体系随Ｃｏ含量的增加由Ｓｒ４Ｆｅ６－ｘＣｏｘＯ１３＋δ层着相逐步变为含钙钛矿等物相的多相区。     

纳米湿敏陶瓷α—Fe2O3—Al2O3—K2O的制备与性能

采用溶胶－凝胶法新工艺制备了不同配比的纳米级α－Ｆｅ２Ｏ３－Ａｌ２Ｏ３－Ｋ２Ｏ复合氧化湿敏陶瓷。ＸＲＤ、ＢＥＴ比表面吸附、Ａｒｃｈｉｍｅｄｅ排水法等手段对系列纳米陶瓷物相及微结构进行了分析表征。湿敏特性测试结果表明：调控各组分摩尔配比为ｒ（Ｆｅ：Ａｌ：Ｋ）＝９０：５：５,可获得全湿区阻－湿特性线性关系良好、感湿灵敏度较高、湿滞小、使用温度范围宽、响应速度较快、性能一致性优的湿敏元件。提出组份间界面     

Cr_2O_3在SiO_2-Al_2O_3-MgO-B_2O_3系玻璃和玻璃陶瓷中的作用

利用ＳＭＥ和ＸＲＤ等技术,系统研究了Ｃｒ２Ｏ３对ＳｉＯ２－Ａｌ２Ｏ３－ＭｇＯ－Ｂ２Ｏ３系玻璃和玻璃陶瓷中的作用。当Ｃｒ２Ｏ３％＜１时,随着Ｃｒ２Ｏ３。含量的增加,玻璃试样的颜色由浅绿色逐渐转变成灰色;Ｃｒ２Ｏ３％＞１时,镁铬（铝）类晶石,Ｍｇ（Ａｌ１．５Ｃｒ０．５）Ｏ４,在玻璃试样中析出;在玻璃陶瓷中,Ｃｒ２Ｏ３％的含量的增加有助于Ｍｇ（Ａｌ１．５Ｃｒ０．５）Ｏ４相的析出,对云母晶体的析出有抑制作用。同时还发现Ｃｒ２Ｏ３的含量对云母晶体显微组织也有显著的影响作用。     

(K0.5Na0.5)(TaxNb1-x)O3无铅压电陶瓷的性能特征

采用传统电子陶瓷制备工艺制备了(K0.5Na0.5)(TaxNb1-x)O3无铅压电陶瓷。研究了不同Ta含量下(K0.5Na0.5)(TaxNb1-x)O3陶瓷的晶相组成及性能特征。结果表明,(K0.5Na0.5)(TaxNb1-x)O3陶瓷在低Ta含量时形成单一斜方相固溶体,但Ta含量达到0.08mol后则有K6Ta10.8O30次晶相产生。随着Ta的加入,陶瓷的体积密度逐渐增大,居里温度(Tc)逐渐降低。当Ta含量为0.08mol时陶瓷具有良好的铁电、压电性能和介电稳定性能,其压电常数d33为76pC/N。     

Co取代对Nd(Zn0.5Ti0.5)O3微波介质陶瓷结构与性能的影响

采用传统固相法制备Nd[(Zn1?xCox)0.5Ti0.5]O3 (0≤x≤0.9)微波介质陶瓷,研究Co2+在B位取代Zn2+对Nd(Zn0.5Ti0.5)O3微波介质陶瓷的结构和微波介电性能的影响. 结果表明,在研究的组分范围内,Nd[(Zn1?xCox)0.5Ti0.5]O3陶瓷均能形成单斜钙钛矿型固溶体,随Co取代量增加,陶瓷的相对介电常数?r逐渐减小,谐振频率温度系数?f逐渐向负值移动,品质因数Q×f先增大后下降,在x=0.3 mol时达到最大值215130 GHz, Q×f大幅增加是有序度作用所致. 在1410℃下烧结4 h, Nd[(Zn0.7Co0.3)0.5Ti0.5]O3陶瓷具有优异的微波介电性能,?r=31.2, Q×f=215130 GHz, ?f=?35.7×10?6℃?1.     

复相陶瓷(0.5BaO0.5SrO)[(1-y)TiO2yNb2O5]的介电性能研究

通过对组成进行一定的过量控制，利用传统陶瓷工艺，成功制备了具有钙钛矿相钛酸锶钡固溶体和钨青铜相铌酸锶钡固溶体两相稳定共存的(0.5BaO0.5SrO)[(1-y)TiO2yNb2O5](BSTN)复相陶瓷.用Riguaku D/max-2400型X射线衍射仪和KEITHLEY 3330阻抗分析仪对所得样品的相结构状态及介电性能进行了测试.结果表明：Y值在0.1～0.7之间的BSTN复相陶瓷为钙钛矿相和钨青铜相两相稳定共存的复合相；在该范围以外，则为单一相的钛酸锶钡与Nb或铌酸锶钡与Ti的固溶体.复相陶瓷的介电性能取决于钙钛矿相和钨青铜相的相对含量及其固溶度，当组成y约为0.7时，介电常数达到最大值；随测试频率的提高，介电常数和损耗降低.复相陶瓷中钨青铜相的铁电/顺电相转变温度与钨青铜相中固溶TiO2量相关，随固溶量增加，转变温度降低.同时，受复相陶瓷中钙钛矿相的影响，随钙钛矿相相对含量的增加，转变温度升高；钨青铜相的最低铁电/顺电相转变温度出现在约110℃，比Sr0.5Ba0.5Nb2O6下降约240℃.     

Aging effect in Er3+-doped 0.5Ba(Zr0.2Ti0.8)O3–0.5(Ba0.7Ca0.3)TiO3 ceramics

Usually, aging in poled ferroelectrics leads to degradation of certain physical properties. In this study, we found a remarkable aging effect in tetragonal Er³⁺-doped 0.5Ba(Zr_0.2Ti_0.8)O₃–0.5(Ba_0.7Ca_0.3)TiO₃ (BZT-BCT) ceramics after poling. It is observed that the domains can spontaneously rotate to keep their spontaneous polarization direction similar to that of the poling electric field during aging for the poled ceramics. Furthermore, compared with freshly poled ceramics, the thermally stimulated current (TSC) peak of the aged ones shifts toward a higher temperature (10°C). And the temperature of the TSC peak in the aged ceramics is exactly equal to their Curie temperature. Such features indicate that aging for the poled ceramics could stabilize the alignment of ordered ferroelectric domains. Additionally, a downward TSC peak above Curie temperature is obtained in both poled and aged ceramics, demonstrating that poling and aging can lead to ordered alignment of defect dipoles. The aging mechanism of poled Er³⁺-doped BZT-BCT ceramics has proposed and discussed in this article.     

Room-temperature ferromagnetism in (K0.5Na0.5)NbO3-xBaNi0.5Nb0.5O3-δ ferroelectric ceramics with narrow bandgap

In this paper, a simple, reproducible and cost-effective solid-state reaction sintering process is developed to fabricate (K_0.5Na_0.5)NbO₃-xBaNi_0.5Nb_0.5O_3-δ (KNN-xBNN) ceramics with a narrow bandgap and room-temperature ferromagnetism. Here, we report a systematic investigation of the influence of the BaNi_0.5Nb_0.5O_3-δ (BNN) concentration on the properties of KNN-xBNN ceramics. All ceramics form orthorhombic perovskite structures with a space group Amm2 and a weak peak at the wavelength of 550 cm^?1 that is characteristic of the pillow shoulder of the orthorhombic phase. KNN-xBNN ceramics with x between 0.02 and 0.08 have a narrow bandgap of about 2.5 eV—much smaller than the 3.5 eV of its parent (K_0.5Na_0.5)NbO₃ (KNN) ceramic—which is attributed to Ni²⁺-oxygen vacancy combinations (Ni²⁺-V_O) raising the valence electron energy level of the KNN ceramic. Furthermore, doping BNN into KNN ceramics can significantly convert the magnetism from diamagnetism to ferromagnetism and the component of x = 0.08 achieves both maximum saturation magnetisation intensity (14 memu/g) and minimum coercive magnetic field (80 Oe). Our findings provide a systematic insight into the bandgap tunability and ferromagnetism induction at room temperature in lead-free perovskite KNN-xBNN ceramics, as well as demonstrate their potential applications in perovskite solar cells and multiferroic devices.     

CeO2掺杂钛酸铋钠钾陶瓷的制备工艺与介电性能

为了进一步探索合成工艺对钛酸铋钠系无铅材料的结构及介电特性的影响,本文以甘氨酸为燃料,利用固相-燃烧法制备了CeO2掺杂的Bi0.5Na0.5TiO3-Bi0.5K0.5TiO3 (BNKT)陶瓷.XRD表明,在固相合成工艺中引入燃烧法制备BNKT陶瓷,比传统固相法降低预烧温度150 ℃,掺杂的CeO2扩散进入了BNKT钙钛矿的晶格,且当掺杂量为0%~0.3%时,形成纯的钙钛矿相结构;SEM表明,CeO2掺杂使晶粒尺寸趋于平均,对晶粒生长有抑制作用;介电温谱表明,随着CeO2掺杂量增加,介电常数εr和退极化温度Td、相转变温度Tm降低,介电反常峰逐渐弱化,且室温至300 ℃,介电损耗tanδ始终在0.3%以下,并从微结构缺陷空位形成机制角度,结合铁电畴壁运动状态,分析讨论了对材料介电特性的作用规律.     

Reducing dielectric loss in Na0.5Bi0.5TiO3 based high temperature capacitor material

The demand for capacitors exhibiting low sensitivity towards temperature changes and high power peaks has increased significantly. Recently, Na_0.5Bi_0.5TiO₃ (NBT) based ceramics became excellent candidates for such extreme temperature capacitors. The dielectric loss of these materials is, however, difficult to control because of the complex defect chemistry of NBT based ceramics. Therefore, it is the limiting factor for high temperature applications. In this work, we present a strategy to increase the upper temperature limit for low dielectric loss. The addition of BiAlO₃ to Na_0.5Bi_0.5TiO₃-BaTiO₃-CaZrO₃ reduces the loss and sensitivity towards Bi evaporation during synthesis. For unmodified samples, the relative permittivity (ε_r = 581, at 1 kHz) varies less than 15 %, while the dielectric loss stays below 0.02 between -68 and 368 °C. With the addition of BiAlO₃, the temperature range of low loss extends from -68 to 391 °C at even higher permittivity (ε_r = 628, at 1 kHz).     

Enhanced piezoelectric properties of Sr(1.7)(Na0.5Bi0.5)0.3Bi4Ti5O18 ceramics in the system Sr(2−x)(Na0.5Bi0.5)xBi4Ti5O18 (where 0 ≤ x ≤ 0.5)

Fine powders synthesized via sol-gel route were employed to fabricate Sr_(2−x)(Na_0.5Bi_0.5)_xBi₄Ti₅O₁₈ (SNBT, where x = 0, 0.1, 0.25, 0.3, 0.4, and 0.5) ceramics. The composition (x)-dependent structural changes associated with SNBT ceramics were analyzed using X-ray powder diffraction, transmission electron microscopy, and Raman spectroscopic techniques. Average grain size analyses carried out on the SNBT ceramics by scanning electron microscopy revealed an important role played by the dopants in inhibiting the grain growth. Dielectric constants and the Curie temperature of the ceramics were found to decrease and increase, respectively, with increase in x. The increase in Curie temperature with increase in x was attributed to the decrease in the tolerance factor. The specific composition (x = 0.3) of the SNBT ceramics exhibited improved piezo- and ferroelectric properties associated with a higher Curie temperature (569 K). The piezoelectric coefficient (d₃₃) and the planar electromechanical coupling coefficient (k_p) of SNBT(x = 0.3) were enhanced by 25% and 42%, respectively, as compared to the undoped ceramics.     

铁掺杂钛酸铋钠钾陶瓷的制备及表征

采用传统固相法制备了无铅压电陶瓷Bi0.5(Na0.825K0.175)0.5TiO3+xFe2O3(x为质量分数,0、0.1%、0.3%、0.5%、0.7%、1.0%、1.5%)(简写BNKTF-x),利用X射线衍射(XRD),和扫描电子显微镜(SEM)等分析表征了该体系陶瓷的结构、介电与压电性能。XRD测试表明,在1 180℃、2 h的烧结条件下,当铁的质量分数小于1.0%时,陶瓷呈现单一相的钙钛矿结构。所有陶瓷晶粒大多呈四方晶形,晶界明显。增加铁的含量有利于晶粒生长。此外,铁的加入也使陶瓷样品气孔率降低,当铁的质量分数在0.3%左右时陶瓷的致密性最好。BNKTF-0.1%体系陶瓷具有较好的电学性能:d33=145 pC/N,kp=0.28,εr=869,tanδ=0.032,Qm=106。     

La_2O_3掺杂(Bi_(0.5)Na_(0.5))_(0.94)Ba_(0.06)TiO_3陶瓷的介电和压电性能的研究

用固相反应法制备La2O3掺杂的铁电陶瓷(Bi0.5Na0.5)0.94Ba0.06TiO3(BNBT6)。X射线衍射曲线表明掺杂0-0.6wt%La2O3的BNBT6为钙钛结构。研究了La2O3掺杂对BNBT6陶瓷介电性能和压电性能的影响。结果表明La2O3掺杂量为0.3wt%的BNBT6陶瓷综合性能最佳,其中介电常数为1981.4,介电损耗为0.0625和压电常数为145pc/N。SEM图象表明La2O3掺杂提高了陶瓷的致密度。