火焰原子吸收法测定铜精矿中锑

本文研究了铜精矿中锑的原子吸收光度法的测定.方法简单.快速、准确.特征浓度为0.25μg/ml1%吸收,检出限为0.025μg/ml,标准加入回收95.4～100%,变异系数3.5%.     

火焰原子吸收法测定石灰石中氧化镁

本文研究了用液化石油气作燃料,火焰原子吸收法测定石灰石中氧化镁的分析方法。该方法准确,快速,操作简单,分析成本低,测量范围０．１％￣４．０％。     

火焰原子吸收法测定钨铁中锰,铜

研究用火焰原子吸收法测定钨铁中锰和铜的实验条件，以及在此条件下部分干扰的消除。     

火焰原子吸收法测定钨铁中铜量

研究了用草酸 -过氧化氢分解样品 ,并探讨了酸度、干扰离子对测定结果的影响 ,提出了用火焰原子吸收光谱法测定钨铁中铜量     

火焰原子吸收法测定球墨铸铁中的镁

于稀硝酸体系中，用氯化锶作释放剂，有火焰原子吸收光谱法测定球墨铸铁中的镁，铁、锰、硅、锶等元素对测定无明显干扰。对球墨铸铁中微量镁的测定，相对标准偏差（n＝7）为2．0％。     

火焰原子吸收法测定铋合金中银

本文研究了在硝酸介质中，于速长328．1nm处用原子吸收光谱法分析铋合金中银的分析方法．此法操作简单、快速、结果准确、效果好，线性范围宽(0．0002％--5％)．     

火焰原子吸收法测定水样中的镉

本文采用硝酸消解水样,建立了火焰原子吸收法直接测定水样中镉的方法。对溶样方法、共存离子干扰等进行了讨论。结果表明,在选定的实验条件下,水样中共存离子不干扰镉的测定。方法的线性范围为0.05~1 mg/L,方法检出限为0.011 mg/L。将本方法应用于实际水样的分析,相对标准偏差在1.95%以下,回收率在98%~102%之间。     

火焰原子吸收法测定高铋物料中的铅

本文介绍了在以高铋物料为基体 ,5 %的HNO3 介质中 ,波长 2 17nm处进行火焰原子吸收法测定铅的试验 ,采用标准加入法进行回收率的试验 ,回收率大于 98% ,特征浓度为 0 .0 7μg/ml,结果令人满意 ,能满足炉前样分析的要求     

火焰原子吸收法测定硫酸铜中锰和铬

采用电解法除去主量铜 ,电解后液经浓缩后用火焰原子吸收法测定硫酸铜中微量锰和铬。方法简单、快速 ,准确度高 ,线性关系良好。锰和铬的相关系数分别为 0 .9995、0 .9996 ;回收率为 94%～ 10 5 %及 90 %～10 2 %。     

Nonlinear behavior of Tb4O7-modified ZnO-Pr6O11-based ceramics with high breakdown field

The effect of Tb4O7 on electrical behavior of the ZnO-Pr6O11-based varistor ceramics was investigated.Microstructural analysis indicated that the addition of Tb4O7 decreased average grain size from 3.6 to 3.2 μm and increased the sintered density from 5.58 to 5.68 g/cm3.As the amount of Tb4O7 increased,the breakdown field increased from 9393 to 12437 V/cm and the nonlinear coefficient increased from 50 to 65.The varistor ceramics added with 0.5 mol.% in the amount of Tb4O7 exhibited an excellent stability by exhibiting-0.1% in the variation rate of the breakdown field,0% in the variation rate of the nonlinear coefficient,and 8.8% in the variation rate of the leakage current density for DC-accelerated aging stress of 0.85 E1 mA/115℃/24 h.     

Luminescent properties of amorphous phosphor 1.4YeO3·2.5Al2O3·0.1Tb2O3 prepared by sol-gel method

Amorphous phosphor 1.4YeO3·2.5Al2O3·0.1Tb2O3 （the same composition as Y2.8Tb0.2Al5O12） was prepared via a sol-gel method at relatively low temperature （i.e., below 650℃）, which is much lower than that for the preparation of polycrystalline Y3Al5O12：Tb^3＋ （above 1400℃）. The amorphous phosphor prepared in the optimized conditions showed a bright green-yellowish luminescence, the intensity of which was comparable with that of polycrystalline sample and the emissions of which were assigned to 5D4 → 7Fj transitions of Tb^3＋. Besides the emissions of Tb^3＋, the amorphous samples prepared at temperatures below 500 ℃ presented a weak blue emission band around 420 nm.     

Li4SiO4-Y2O3的溶胶-凝胶法合成及离子导电性研究

用溶胶-凝胶法制备了Li4SiO4-xY2O3(x=0～0.5)离子导体材料,并用DTA-TG、XRD及交流阻抗等技术对样品进行了测试,结果发现用溶胶-凝胶法可降低Li4SiO4的合成温度并可提高离子的导电性,适量Y2O3的掺入可增强基质的致密性,并可提高材料的导电性能.     

Na3PO4—Na2B4O7体系中钛合金微等离子体氧化陶瓷膜研究

在钛合金上用微等离子体氧化法制备氧化膜,用扫描电镜（SEM）、X-射线（XRD）测其表面形貌、相组成,并对现象及测试结果进行分析,。从而推理其成膜机理。     

The thermal decomposition of Mn2O3 and the reduction of Mn3O4 by C and CO

The thermal decomposition of Mn₂O₃ was studied at 1000°. The rate of decomposition was inherently fast and dependent on the mass-transfer characteristics of the geometry used. The rate of reduction of Mn₃O₄ by CO, coconut charcoal, coke, and pure graphite was investigated in the temperature range 900 to 1200°. It was found that the rate of reduction in CO was fast and that the overall rate of reduction by carbon was determined by the oxidation of the carbon by CO₂. In general the rate was higher for higher tempera tures and for smaller particle sizes of the oxide and the carbon. Gases such as He, Ar, or N₂ were found to decrease the rate because of the dilution effect due to back diffusion into the interparticle pores of the oxide-carbon mixture. It was further found that the oxidation of carbon by CO₂ was catalyzed by Mn₃O₄. This effect was particularly pronounced when the reductant was either graphite or coke.     

Superconducting Transition Temperature in YBa2Cu4O8/La2/3 Ca1/3 MnO3 / YBa2 Cu4O8 Heterostructure

YBa2Cu4O8/La2/3 Ca1/3 MnO3/YBa2Cu4O8 （ Y-124/LCMO/Y- 124） heterostructure was prepared by facing-target sputtering technique. The oscillatory superconducting transition temperature was observed when the thickness of LCMO d L is larger than critical thickness d L^CR. The metal-insulator transition temperature can only be detected at d L 〉 d L^CR. The dependence on the spacer layer in LCMO/Y-124 systems suggests strongly the interplay of ferromagnetic and superconducting couplings.     

用菱锰矿制备四氧化三锰工艺研究

用硫酸溶液浸出菱锰矿制得硫酸锰溶液,对硫酸锰溶液进行净化提纯,用氨水沉淀得到氢氧化锰,氢氧化锰沉淀经脱硫处理、洗涤后,用空气或氧气对洗涤后的氢氧化锰沉淀进行氧化,最后经洗涤、烘干得到四氧化三锰成品;进行了副产品硫酸铵回收工艺研究。工艺简单易行,成本低廉,回收率高,而且制得的产品纯度高、比表面积大。     

低温燃烧合成法制备粒径相近的MnO、Mn3O4和Mn2O3纳米颗粒

通过控制硝酸盐(硝酸锰) 与有机燃料(尿素) 的摩尔比, 采用低温燃烧合成法制备了粒径相近、形貌不同的单相MnO、Mn₃O₄和Mn₂O₃纳米粒子。扫描电子显微形貌观察结果显示, 三种纳米粒子尺寸约为100 nm, 依据Mn离子价态的不同, 三种纳米粒子的形貌分别为链状、马铃薯状和球状; 热重-差热分析表明, 样品粒径大小主要取决于有机燃料的着火点; 磁性测量结果显示, 低温时MnO和Mn₂O₃粒子表现出弱铁磁性, 这主要归因于纳米颗粒表面存在未补偿的自旋。本文为制备不同价态高纯锰氧化物纳米颗粒提供了一种环境友好、工业稳定的途径。     

助熔剂种类对绿色荧光粉(Ce0.67, Tb0.33)MgAl11O19晶体结构、形貌及发光强度的影响

采用高温固相法制备了三基色荧光灯用(Ce_0.67, Tb_0.33)MgAl₁₁O₁₉（CMAT）绿色荧光粉,研究了MgF₂、AlF₃、Li₂CO₃和H₃BO₃4种助熔剂对CMAT绿粉物相纯度、粉体颗粒形貌和发光强度的影响。结果表明,用H₃BO₃做助熔剂制备的CMAT绿粉在物相纯度、粉体颗粒形貌和发光强度方面都优于其它三者。