含取代茚基配体稀土金属有机化合物的合成、表征及催化性能

采用Schlenk技术,在干燥纯氩气保护下,用无水三氯化稀土LnCl3与2-苯基茚以1∶2的摩尔比在THF中反应,得到8种新配合物:(2-ph-Ind)2LnCl(A)[Ln=La(1),Pr(2),Nd(3),Sm(4),Gd(5),Dy(6),Yb(7),Y(8)]。再用(A)和LiN(TMS)2在THF中反应,得到两种新的二(2-苯基茚)稀土有机配合物:(2-ph-Ind)2LnN(TMS)2(B)[Ln=Y(1),Sm(2)]。所有配合物都经元素分析、红外和质谱鉴定。配合物(B)在甲基丙烯酸甲酯(MMA)的聚合反应中显示出一定的活性。     

Synthesis of the Early Lanthanide Complexes[Li(DME)_3][MeCpLn(NPh_2)_3](Ln=La,Pr,Nd)and X-Ray Crystal Structure of La Complex

The reaction of MeCpLnCl·2LiCl·nTHF with 2 equivalent of LiNPh_2 in THF,hexane andtoluene mixture solution gives the new complex[Li(DME)_2][(η~5-MeCp)Ln(NPh_2)_3](Ln=La,Pr,Nd)byextraction with DME.They have been characterized by elemental analysis,IR and NMR.The La complexcrystallizes in the monoclinic space group P2_1/c with α=1.8335(6)nm,b=1.6576(5)nm,c=1.7461(6)nm,β=96.04°,V=5.277 nm~2,Z=4,D_c=1.26g·cm~(-3),R=0.057 and R_w=0.048(1≥2.5σ(I_o))for 3378 reflec-tions.The complex consists of a pair of a cation and an anion.La~(3+) is coordinated by onemethylcyclopentadienyl and three diphenylamidos to form six-coordinate pseudotetrahedron with the meanLn-N and La-C(ring)distances of 0.2459(8)and 0.2843(11)nm,respectively.     

Organolanthanide Compounds Containing Methanesulfonate and Pyrazinamide Ligand in Styrene Polymerization

The synthesis of organolanthanide compounds identified as LnCp*(MS)2PzA, Ln=Sm, Tb, Yb (MS=methanesulfonate, Cp*=pentamethylcyclopentadienyl, and PzA=pyrazinamide), by the reaction of coordination compounds Ln(MS)3(PzA)4 with NaCp in THF was reported. The complexes were formulated according to elemental analyses, complexometric titration with EDTA (%Ln), and 1H NMR. IR spectroscopy revealed that PzA coordinates with lanthanide(Ⅲ) ions and methanesulfonate coordinates via oxygen atoms in a non-equivalent manner. In preliminary catalytic studies, these compounds were active in styrene polymerization that used MAO as a cocatalyst with an activity of 12.3 kg PS mol Sm-1h-1. Differential scanning calorimetry (DSC) of polystyrene showed that the polymer was mainly atactic.     

我国钨工业化学分析进展

系统综述和讨论了近十年我国钨工业化学分析的进展,包括化学分析、分光光度分析、化学发光与荧光分析、原子吸收光谱分析、原子发射光谱分析、电化学分析、Ｘ荧光光谱分析及其它分析方法研究及应用。     

Advances in Modeling Completely Mixed Flow Reactors for Ion Exchange

This work advances the mathematical modeling of ion exchange treatment in completely mixed flow reactors in which there is recycle and regeneration of the ion exchange resin. The most common application of this process is magnetic ion exchange resin to remove dissolved organic carbon from raw drinking water. The motivation for this work was the complex distribution of resin particle ages and sizes that result from the recycle and regeneration processes. The newly developed model uses a single “age-averaged” diffusion equation to represent resin particle age as compared with the previous Monte Carlo model that uses a large number of diffusion equations to represent various resin particle ages. Advantages of the age-averaged model over the Monte Carlo model include a closed-form analytical solution for the steady-state case of the model, advanced numerical techniques used for the nonsteady-state case of the model, and model simulations require much less computational time and yield more accurate results. The age-averaged model is a robust numerical tool that can be used to evaluate a range of treatment scenarios as a result of these advancements.     

Advances and prospects of rare earth metal-organic frameworks in catalytic applications

In recent years,rare earth metal-organic frameworks(RE-MOFs) have attracted increasing attention because of abundant coordination behaviors,adjustable channels and stable networks.The various electron structures of rare earth ions contribute to the catalytic applications of RE-MOFs and their derivates.In this review,we systematically summarize the research progress that using RE-MOFs and their derivates as catalysts for organic reaction,photocatalytic reaction,and CO oxidation reaction.The major parts include synthetic strategies and catalytic applications of the RE-MOFs.Finally,impressive achievements of RE-MOF catalysts are emerging and a prospect is provided for the development of RE-MOF catalysts at the end of the review.     

Rare earth elements: Properties and applications to methanol synthesis catalysis via hydrogenation of carbon oxides

Methanol (CH₃OH) is an important industrial chemical with a wide variety of uses. Industrial methanol synthesis catalysts are typically composed of Cu, Zn, and Al, but the use of catalysts incorporating rare earth elements has been shown to improve the catalytic performance. Due to their unique chemical and physical properties, the use of rare earth elements (scandium, yttrium, and the lanthanides) in catalysis in general has continued to increase over the past few decades, while the use of rare earth in methanol synthesis catalysts has not, despite often improving performance. The ability of several of the rare earth elements (Pr, Ce, Eu, Tb, Yb) to easily switch between oxidation states makes them beneficial for many different types of catalysts. However, for methanol synthesis the surface basicity is an important property, and the basic nature of the rare earth elements can be used to tune the basicity of catalysts. A small number of correlations between rare earth properties and catalytic performance have been observed, but often do not apply to other catalysts. Properties such as strength of basic sites, ionic radius, and electronegativity have been found to correlate with performance results such as activity or selectivity.     

Advances in Modern EAF Steelmaking Technology of China

In the recent decade, the remarkable achievements have been made on steelmakingtechnology with electric arc furnace (EAF) in China, on the basis of importing and assimilatingnew technologies from abroad and making innovation. The integrated control theory of tap-to-tap time and electric power consumption of modern EAF was put forward and hence showed theresearch direction to shorten tap-to-tap time, decrease electric energy consumption and increaseproductivity and the basis to select rated power of transformer. EAF steelmaking technologywith hot metal charging, terminal point control (TPC) technology, bottom blowing technologywith nitrogen instead of argon and low nitrogen steel producing technology were obtained. Fi-nally, the structure model of raw materials was presented.     

我国香蘑属真菌研究进展

综述了我国香蘑属真菌在种质资源、营养成分、药理学与栽培技术等方面的研究进展,探讨了我国香蘑属的研究方向和前景.     

我国钛白生产的技术进步

文章总结了我国钛白生产的技术进步,希望对读者有所帮助。     

中国金刚石的发展及其性能研究

近年来, 中国合成金刚石年产约20亿ct, 已跃居世界第一。合成金刚石压机绝大多数为中国自主开发的独具特色的铰链式六面顶压机, 目前正向大吨位、高精度、程控方向发展。沿用多年的片状触媒与片状石墨合成工艺正和粉状触媒与粉状石墨合成工艺齐头并进地发展。此前, 中国金刚石的质量有了大幅提高, 某些品牌的金刚石的冷冲指数(TI)和热冲指数(TTI)与国外同类产品相当。影响金刚石性能的残留触媒质量分数为0.1%~0.4%, 其成分与合成金刚石所用触媒成分相近, 残留触媒形状不一, 本身不致密, 与金刚石之间有间隙, 对金刚石强度性能产生影响是由于金刚石与残留触媒之间存在界面反应。     

十年来我国无机光度分析的成就和进展

本文简要地总结并回顾了近十年来我国无机光度分析及荧光分析的成就和进展。全文主要包括:(1)新型有机显色剂及荧光试剂的合成及应用;(2)超灵敏光度分析体系的进展;(3)表面活性剂胶束增效作用的研究;(4)多波长、导数光谱、高效液相色谱以及流动注射分析等新技术与光度分析的结合;(5)化学计量学及其在多组分同时测定中的应用。全文附有参考文献271篇。     

中国黑白钨混合矿选矿工艺研究进展

系统地介绍了复杂难选的黑白钨混合矿的选矿工艺进展及发展方向。基于黑白混合矿其伴生组分复杂,原矿品位低,嵌布粒度细等特点,选别难度相对较大。目前在新型高效的浮选药剂和选矿设备开发利用的基础上,采用以浮选为主,结合重选、磁选等多种选矿方法的联合工艺处理黑白混合钨矿取得了较好的试验指标,在钨选矿生产实践中得到应用。选冶联合流程针对复杂难处理的钨矿具有良好的效果,探索简单有效,技术经济合理的选冶联合工艺是今后钨矿选矿发展的重要方向。     

Synthesis and Spectral Properties of Mixed-Ligand Complexes of Lanthanide Perchlorate with Bis-(phenylsulfinyl)ethane and Organic Lewis Bases

ＳｙｎｔｈｅｓｉｓａｎｄＳｐｅｃｔｒａｌＰｒｏｐｅｒｔｉｅｓｏｆＭｉｘｅｄＬｉｇａｎｄＣｏｍｐｌｅｘｅｓｏｆＬａｎｔｈａｎｉｄｅＰｅｒｃｈｌｏｒａｔｅｗｉｔｈＢｉｓ（ｐｈｅｎｙｌｓｕｌｆｉｎｙｌ）ｅｔｈａｎｅａｎｄＯｒｇａｎｉｃＬｅｗｉｓＢａｓｅ...     

我国钨矿床中伴生银的赋存状态及其综合利用

我国钨矿资源丰富 ,与其伴生的有用元素多达十几种 ,其中伴生银的含量一般可达n×10g/t,普遍具有综合利用价值。钨矿床中的伴生银主要以银的独立矿物的形式存在 ,大部分分布在其金属硫化物载体中。通常利用回收其载体矿物的方法实现对银的回收 ,以往其回收率一般不高 ,要实现充分合理地利用资源 ,还必须开展银的工艺矿物学方面的研究 ,以此作为对银的综合利用前景评价以及确立对银的选矿作业的科学依据 ,力求提高银的回收率 ,以适应矿山开展综合利用的需要     

Combined Effects of Aging and Cosolvents on Sequestration of Phenanthrene in Soils

The objective of this study is to investigate the effect of organic cosolvents on the extractability of hydrophobic organic compounds (HOCs) from soils after defined aging periods following HOC contamination. Phenanthrene was used as the representative HOC. Two soils with organic matter contents 2.9 and 6.5%, respectively, were investigated. The soils were spiked with phenanthrene, then saturated in water or mixtures of water and methanol, and aged for up to 422 days. After freeze drying, the extent of phenanthrene release was measured using a mild extraction process. The results show that as aging period increases, phenanthrene removal from the soils becomes more difficult. The amount of easily extractable phenanthrene tended to increase when more methanol existed in the pore fluid during aging, but the difference largely diminished after about 400 days. At the early stage of aging, extraction of phenanthrene from the soil with lower organic matter content tended to be less difficult compared with that from the soil containing more organic matter. The opposite appeared to be true when the aging time was longer than 200 days. From the results, we propose that a shift in the predominant sequestration mechanisms occurred after a certain period of time, in which hydrophobic interactions between HOCs and organic matter gradually yield to physical trapping of the sorbate molecule in the meso- and micropores of the soil particles.     

介孔锰氧化物的制备研究进展

结合近几年来对介孔锰氧化物的研究进展,对介孔锰氧化物的制备方法和研究情况作了比较全面的综述。对包括自组装合成法、表面活性剂模板合成法、溶胶—凝胶法、高温水热法、水解法和超声波法等合成方法的有关机理、特点、影响因素等进行了简单的讨论,对介孔锰氧化物的合成提供了必要的指导。     

国内PDP用绿色荧光粉的研究进展

简要介绍了目前国内等离子体显示器（PDP）用绿色荧光粉的研究现状及合成研究进展，并展望了其发展前景。