Crystal structure and magnetic behavior of novel R2PdIn8 (R = Pr, Nd, and Sm) compounds

A new series of R₂PdIn₈ intermetallics, where R = Pr, Nd, and Sm, was prepared by arc-melting the constituents under argon atmosphere and studied by means of X-ray diffraction and magnetic measurements. The compounds crystallize with a tetragonal structure of the Ho₂CoGa₈ type (space group P4/mmm). At very low temperatures, they order antiferromagnetically, and the Nd-based indide presumably exhibits an additional magnetic phase transition in the ordered region.     

Potentiometric study of the interaction of Cr and O ions in fused NaCl-2CsCl eutectic

The physical and chemical properties of chromium chlorides have been studied in fused NaCl-2CsCl eutectic at the temperature range 843-1008 K using an electrochemical cell containing a platinum-oxygen electrode with solid electrolyte membrane, which was used as pO²⁻ indicator electrode. The concentration of oxygen ions in the solution was modifying by dropping the calculated amount of BaO. Titration of Cr³⁺ chlorocomplex by O²⁻ ions demonstrated the precipitation of CrOCl and Cr₂O₃. The solubility constants of these compounds were calculated. E-pO²⁻ and three-dimensional E-pO²⁻-T type diagrams, which summarized the properties of chromium species in the melt, were determined.     

Zinc-mediated novel and efficient method for N-sulfonylation of amines in the absence of base

A simple and efficient method of zinc dust-mediated N-sulfonylation of amines to the corresponding sulfonamides is described. The reaction is carried out under neutral and mild conditions. The significant feature of this method is the isolation of the pure product by simple work up in a short time.     

稀土添加剂在硬质合金中的应用研究

对国内含稀土元素的硬质合金10多年来的研制情况及稀土元素对硬质合金组织和性能的影响进行了概述。     

Ce掺杂对TbFeCo材料磁光性能影响的研究

采用射频磁控溅射方法制备了TbFeCo非晶磁光薄膜，并在TbFeCo中引入轻稀土元素Ce，测试了薄膜的磁光性能。研究了薄膜成分对其磁光性能的影响。结果表明；在TbFeCo薄膜中掺入少量Ce时，薄膜的磁光克尔角及矫顽力都有所提高，矩形度也增加了。但随Ce掺入量的增加，薄膜的磁光性能发生恶化，较好的掺杂在10.31?左右。     

稀土在人棉灯芯绒直接染料染色中的应用

目前，稀土在化纤类，毛类纺织品染色中的应用比较成熟，而在棉类染色中的应用还未能得到推广，探讨稀土在直接染料对人棉灯芯绒织物染色中的作用机理，并从试验和生产方面加以比较，总结出本厂的成熟工艺。作者认为稀土对人棉灯芯绒织物在直接染料染色上应用是切实可行的，效果是理想的。     

Energy transfer and luminescence properties of Eu-doped NaTb(WO4)2 phosphor prepared by a facile hydrothermal method

NaTb_(1−x)Eu_x(WO₄)₂ (x = 0-100%) phosphors have been synthesized via a mild hydrothermal process directly without further sintering treatment. X-ray diffraction (XRD), scanning electron microscope (SEM), photoluminescence excitation and emission spectra and decay curve were used to characterize the samples. Moreover, the luminescence colors of NaTb_(1−x)Eu_x(WO₄)₂ (NTbW:Eu) samples can be tuned from green, green-yellow, and yellow to red by simply adjusting the relative Eu³⁺-doping concentrations under a single wavelength excitation, which might find potential applications in the light displays systems.     

Maintaining Groundwater Supplies during Drought Conditions in the Brighton Area

The very low level of recharge to the chalk of the South Downs, which provide Brighton with its water supply, has meant that the groundwater levels are very low. Despite this, no restrictions have been necessary since February 1991. This is perhaps due to the instigation of public information campaigns, together with media coverage of the drought, as well as a successful programme of leakage control. This paper looks at how the growth of public water supply has been accommodated operationally while ensuring that groundwater quality is maintained. Options for the future expansion of supply, and their cost-effectiveness, are also considered.     

Application limits of stainless steels in the petroleum industry

Stainless steels have a great variety of potential applications in the petroleum industry, mainly as an alternative to carbon steel in corrosive environments. Within a number of media that can cause corrosion problems with these materials, only chloride solutions and hydrogen sulfide are of importance in oilfield service. A reliable tool that permits the proper selection of stainless steels has yet been missing. In order to provide engineering diagrams for this purpose, pitting and stress corrosion cracking (SCC) tests were performed. Specimens were exposed to NaCl solutions containing from 3 to 100,000 ppm Cl^? at temperatures from 40 to 200 °C. This test configuration was chosen to give a better representation of actual service conditions than accelerated standard test procedures do. Tested materials were the austenitic stainless steel grades 321, 316Ti (API LC30‐1812) and 254 SMO, and 22Cr duplex (austenitic‐ferritic) steel (API LC65‐2205). Based on an optical examination of the specimens, no‐risk regions of chloride concentration vs. temperature have been identified. Subsequently, service temperature limits have been deduced for each tested material. Thus, material failures by pitting and SCC can be prevented without overdesigning. The results of the testing series are applicable to all chloride environments without presence of H₂S, as they have to be handled by primary production equipment, as well as transportation and gas processing facilities.     

稀土离子掺杂铝酸盐长余辉发光材料的研究进展

综述了长余辉发光材料的国内外研究进展，并以稀土离子激活的铝酸盐体系为例，从发光机理、合成方法和研究现状等方面进行了全面的分析。特别对飞秒激光诱导下的长余辉发光玻璃的研究情况进行了详细介绍，对发展前景和研究方向进行了展望。