LaCrO_3－NiMn_2O_4复合陶瓷的结构分析

将尖晶石型ＮｉＭｎ＿２Ｏ＿４及钙钛矿型ＬａＣｒＣ＿３这二者电阻个较高的半导体陶瓷热敏材料复合并经高温烧结后，其复合体电阻率大幅度降低。应用ＸＲＤ，ＸＰＳ，ＴＥＭ和ＳＥＭ对复合体结构进行较为系统的研究，结果表明：ＮｉＭｎ＿２Ｏ＿４与ＬａＣｒＯ＿３按一定比例复合后，在烧结过程中两者之间有离子迁移发生，离子迁移的结果使钙钛矿结构的ＬａＣｒＯ＿３转变为高导电相的Ｌａ［Ｃｒ＿（１－ｘ－ｙ）Ｎｉ＿ｘＭＮ＿ｙ］Ｏ＿３（０＜ｙ＜０，０＜ｘ＋ｙ＜０），它使复合体电阻率大幅度降低。     

LaCrO3基导电材料的研制

分析了ＬａＣｒＯ３基导电材料的导电机理，并对其配方，合成和成型等生产工艺进行了多次试验，探索出合理的工艺参数，设计了简单的实验电炉，用ＬａＣｒＯ３作为发热体进行了升温试验。     

LaCrO3—NiMn2O4复合陶瓷的结构分析

将尖晶石型ＮｉＭｎ２Ｏ４及钙钛矿型ＬａＣｒＯ３这二者电阻率较高的半导体陶瓷热敏材料复合并经高温烧结后，其复合体电阻率大幅度降低。应用ＸＲＤ，ＸＰＳ，ＴＥＭ和ＳＥＭ对复合体结构进行较为系统的研究，结果表明：ＮｉＭｎ２Ｏ４与ＬａＣｒＯ３按一定比例复合后，在烧结过程中两者之间有离子迁移发生，离子迁移的结果使钙钛矿结构的ＬａＣｒＯ３转变为高导电相的Ｌａ［Ｃｒ１－ｘ－ｙＮｉｘＭｎｙ］Ｏ３（０〈ｘ〈１，０〈ｙ     

二氧化碳和丙烷反应制取低碳烯烃的研究

采用 ＮＨ＿３－ＴＰＤ．Ｈ＿２－ＴＰＲ等手段对 Ｃｒ＿２Ｏ＿３／γ－Ａｌ＿２Ｏ＿３．Ｃｒ＿２Ｏ＿３／ＳｉＯ＿２，Ｃｒ＿２Ｏ＿３／ＺｒＯ＿２和Ｃｒ＿２Ｏ＿３／硅藻土等催化剂的酸性和还原性进行了表征；以Ｃ～０＿３＋ＣＯ＿２做探针反应研究了该系列催化剂的催化性能．ＮＨ＿３－ＴＰＤ结果表明．ＮＨ＿３ 在催化剂 Ｃｒ＿２Ｏ＿３／γ－Ａｌ＿２Ｏ＿３上的脱附量最多．而在Ｃｒ＿２Ｏ＿３／ＳｉＯ＿２上的脱附强度最大．Ｈ＿２－ＴＰＲ结果指出活性中心 Ｃｒ～（３－）在各催化剂上存在明显不同．Ｃ＿３＋ＣＯ＿２反应结果表明，丙烷在 Ｃｒ＿２Ｏ＿３／γ－Ａｌ＿２Ｏ＿３上的转化率最大为 ４４．１７％。而 Ｃ～－＿２～Ｃ～＿３在 Ｃｒ＿２Ｏ＿３／ＳｉＯ＿２上的选择性最大为８２．８４％．     

LaCrO3导电陶瓷的研制

ＬａＣｕＯ３导电陶瓷是一种能在氧化气氛中使用的高温发热体新材料。本文作者按照实际使用的样品尺寸了含Ｃａ＾＋２的ＬａＣｕＯ３导陶瓷的低温烧结性和导电性关系。结果表明，Ｃａ＾２＋含量〈１２％时，低温烧结的ＬａＣｒＯ３烧结体电阻率明显降低，当Ｃａ＾＋２含量〉１２％时，烧结体电阻率升高。     

重铬酸钾间接电化学氧化蒽制蒽醌

以Ｃｒ＿２Ｏ／Ｃ为氧化还原电偶，在Ｈ＿２ＳＯ＿４介质中，由Ｃｒ＿２Ｏ氧化蒽制蒽醌，本身还原为Ｃｒ￣（３＋），在电极上再生氧化生成Ｃｒ＿２Ｏ，以循环使用，反应在常温常压下进行。     

稀土紫萝兰色陶瓷颜料

本试验合成了稀土紫萝兰色陶瓷颜料。它具有配方独特、价廉、色泽艳丽的优点。对颜料进行了物相鉴定及元素分析。结果表明，颜料所含晶相可表示为ＸＡｌ２Ｏ３·ＹＣｒ２Ｏ３、（ＡｌｘＣｒｙ）ＰＯ４及ＬａＰＯ４。对发色机理进行了探讨，Ｌａ３＋离子的存在起了很好的助色作用。     

负载于r－Al_2O_3、SiO_2担体上的四核金属羰基簇合物K［CoFe_3

本文采用无水无氧操作技术，合成了空气中不稳定的四核金属羰基簇合物Ｋ［ＣｏＦｅ＿３（ＣＯ）＿（１３）］，并将其负载于ｒ－Ａｌ＿２Ｏ＿３、ＳｉＯ＿２担体上，制成负载型双金属簇催化剂．分别于真空和ＣＯ气氛下，利用原位红外光谱表征了负载双金属羰基簇合物的热脱碳过程，获得了金属簇骨架（ＣｏＦｅ＿３）与担体表面原子相互作用的实验数据。     

内蒙古天然碱液四元体系的相图研究──150℃Na_2CO_3—NaHCO_3—

本文测定了１５０℃ＮａＨＣＯ＿３─ＮａＣｌ—Ｈ＿２Ｏ、ＮａＨＣＯ＿３—Ｎａ＿２ＳＯ＿４—Ｈ＿２Ｏ两个三元体系及１５０℃Ｎａ＿２ＣＯ＿３—ＮａＨＣＯ＿３—Ｎａ＿２ＳＯ＿４—Ｈ＿２Ｏ、Ｎａ＿２ＣＯ＿３—ＮａＨＣＯ＿３—ＮａＣｌ—Ｈ＿２Ｏ和ＮａＨＣＯ＿２—Ｎａ＿２ＳＯ＿４—ＮａＣｌ—Ｈ＿２Ｏ三个四元体系的相平衡数据，结合前人工作，绘制了上述各体系的相图，并对各相图的构成进行了分析讨论。     

镧化合物的甲烷氧化偶联催化活性研究

研究了镧的氧化物，氢氧化物，碳酸盐催化剂的甲烷氧化偶联活性，利用催化剂具备明显活性所需达到的“起始温度”高低作为催化剂活性强弱的判据，得到了各个催化剂的活性强弱次序：ＬａＯＯＨ（Ｌａ（ＯＨ）３）＞Ｌａ２Ｏ２ＣＯ３（Ｂ）＞Ｌａ２Ｏ３＞Ｌａ２Ｏ２ＣＯ３（Ａ）＞Ｌａ２（ＣＯ３）３，使用ＸＲＤ、ＦＴ－ＸＲＤ等分析手段对催化剂进行了表征     

One-step hydrothermal microwave-assisted synthesis of LaFeO3 nanoparticles

Lanthanum orthoferrite (LaFeO₃) powders were synthesized via a highly efficient one-step hydrothermal microwave-assisted synthesis at relatively low temperatures of 240 °C and pressure of 60 bar. The use of microwave irradiation for heating during the synthesis intensifies the LaFeO₃ crystallization process leading to reduced synthesis duration at least 16 times as compared with conventional heating (3 versus 48 h).     

Hydrothermal microwave-assisted synthesis of LaFeO3 catalyst for N2O decomposition

Lanthanum orthoferrite powders were synthesized via one-step hydrothermal reactions under mild conditions using microwave and conventional heating. The use of microwave irradiation during the synthesis allows one to obtain nanocrystalline LaFeO₃ with a higher yield and reduced crystallite and particle size within a 16 times shorter duration (3 hours) at a lower temperature of 220°C as compared to the conventional heating. The catalytic decomposition of nitrous oxide was performed over both samples, it was shown that the sample obtained under microwave conditions demonstrates enhanced activity as a catalyst: N₂O decomposes completely at 700°C over the catalyst formed at microwave conditions, while the comparative catalyst prepared by conventional heating reaches a lower conversion of only 60% at the same temperature and catalytic reaction conditions.     

Additive manufacturing of barium titanate based ceramic heaters with positive temperature coefficient of resistance (PTCR)

Lanthanum/manganese doped barium titanate (BT) based PTCR functional heater elements/structures were fabricated with desirable electrical properties for the first time using Additive Manufacturing (AM). 3D printed components of varying size and shape and prototype honeycomb lattices with high density were achieved through AM. Aqueous, less organic containing (2.5 wt% additives versus 10–30 wt% added typically), eco-friendly ink formulations were developed with suitable rheological properties for 3D printing. For BT prints, the sintered densities of the 3D ceramic parts were found to be >99% TD, highest reported value so far. The microstructure, electrical properties and heating characteristics of the printed PTCR components were studied in detail and their thermal stability evaluated using infrared imaging and benchmarked against commercial PTCR heating element. The heating behaviour of the solid and porous 3D printed components was demonstrated to be similar, paving the way for light weight (?47% reduction in weight) heaters suitable for automotive/aerospace applications and less materials wastage during device fabrication.     

铬铁矿酸浸过程强化及铬铁分离研究进展

铬铁矿是铬盐生产的主要原料来源,铬铁矿酸浸工艺因无Cr（Ⅵ）污染且资源利用率高而备受关注。综述了近年来铬铁矿酸浸过程强化以及铬铁分离方法的研究进展。铬铁矿酸浸工艺是以硫酸为强酸浸出,通过机械活化处理、氧化剂的加入以及微波加热等辅助强化方法,使得铬铁矿能够被高效、快速地浸出。浸出液中的铬铁分离方法主要有针铁矿法、黄铁矾法、萃取法、草酸法、铁蓝沉淀法和莫尔盐法等。多种强化手段与反应过程相结合已成为铬铁矿硫酸浸出工艺的重要研究方向。     

碳酸镧直接电解制备金属镧试验工艺研究

本试验重点研究了碳酸镧电解制取金属镧的工艺条件。通过将碳酸镧直接加入电解炉后,研究熔盐组成、电解温度、原料钐质量对电效的影响因素及碳酸镧回收利用对产品质量的影响。     

Optimizing the performance of porous electrochemical cells for flue gas purification using the DOE method

The DOE model was used to improve the performance of cells for electrochemical gas purification. Three factors were chosen: the amount of graphite, the Lanthanum Strontium Manganate/Gadolinium-doped Cerium oxide weight % ratio, and the Lanthanum Strontium Manganate pre-calcination temperature (with or without Lanthanum Strontium Manganate calcinated at 1000 °C). The effects of the following physical properties were measured: porosity, pore size, shrinkage, and conductivity. The sintered tapes were also characterized with scanning electron microscopy. Graphite was added as a pore former.The work shows, that a change in a factor not only changes the performance property that one would expect, but also influence other properties.     

PVC用衣康酸镧复合热稳定剂的制备与应用研究

采用皂化法合成了衣康酸镧,利用刚果红法考察了与其他热稳定剂的多元复配效果,得到PVC衣康酸镧复合热稳定剂, 通过傅里叶变换红外光谱探讨了复合热稳定剂对聚氯乙烯（PVC）的热稳定机理,并用转矩流变仪、动态力学谱仪测定其加工性能和力学性能。结果表明,衣康酸镧、季戊四醇、硬脂酸钙、β二酮质量比为35∶1∶1∶1时协同效果最佳,可使PVC试样的静态及动态热稳定时间达到66.0 min和36.8 min,并能较好地抑制初期着色性, 其加工性能和力学性能与铅盐体系、硬脂酸镧复合热稳定体系相当,优于钙锌复合热稳定体系;复合热稳定剂在加热初期可减缓PVC脱除HCl的反应速率,抑制共轭多烯的形成,提高热稳定性能。     

Determination of hardness, Young's modulus and fracture toughness of lanthanum tungstates as novel proton conductors

Lanthanum tungstate is a promising material to be used as electrolyte in proton conducting fuel cells, or as a mixed proton-electron conducting membrane for hydrogen separation, and its mechanical properties are crucial for these applications. Lanthanum tungstates with a La/W atomic ratio between 4.8 and 6.0 have been investigated at room temperature at micro/nanoindentation range. Lanthanum tungstates exhibit a strain gradient plasticity at the vicinity of the imprints, which implies that the hardness presents an indentation size effect that was corrected using the Nix and Gao approach. The hardness and Young's modulus have therefore been determined to be 8-9 GPa and 130 ± 15 GPa, respectively. The fracture toughness was estimated to be ∼2 MPa m^1/2 for LWO56 using the Palqmvist equation. Both hardness and Young's modulus did not present a significant dependence with neither the sintering temperature nor the composition. The different imprints were visualized by Atomic Force Microscopy.     

Sintering of Lanthanum Zirconate

Lanthanum zirconate (La₂Zr₂O₇) was prepared by coprecipitating lanthanum nitrate and zirconyl oxychloride at pH 10, followed by ethanol washing. The initial high surface area of ∼304 m²·g⁻¹ decreased very rapidly with increased sintering temperature and decreased to an immeasurably small value after heating at 1200°C for 15 h. The major parameters studied were phase evolution, crystallite size, porosity, surface area reduction, and shrinkage during sintering. Three temperature regions were identified based on these studies: below the crystallization temperature, between the crystallization temperature and ∼1100°C, and above 1100°C. The main contribution of surface area reduction in the region 800°–1100°C was due to surface diffusion; the main contribution above 1100°C was due to grain-boundary diffusion coupled with surface diffusion.