CaO和NaCl焙烧混合稀土精矿过程中的分解反应

用XRD和TG-DTA热分析技术, 研究了含独居石和氟碳铈镧矿的混合稀土精矿在100～1000 ℃焙烧过程中, 添加CaO, NaCl时, REPO4和REFCO3的分解反应. 研究结果表明: 不添加CaO和NaCl时, 仅在377～450 ℃范围内存在REFCO3的分解反应, 其产物是REOF, RE2O3, 以及Ce2O3进一步的氧化产物CeO2, 而REPO4不分解; 添加CaO后在660～750 ℃之间, CaO有3种分解作用: (1) CaO分解REPO4, 其产物是RE2O3和Ca3(PO4)2. (2) CaO分解REOF, 其产物是RE2O3和CaF2. (3) CaO和REOF的分解产物CaF2共同作用分解REPO4, 其分解产物为RE2O3, Ca5F(PO4)3; 添加CaO, NaCl后, 混合精矿的分解率明显提高, NaCl的作用是为反应体系提供了液相, 促进了固相反应物间的传质过程, 加快了反应速度. 与此同时NaCl还可能参加了CaO分解REPO4的反应.     

四元体系KCl-ZnCl2-HCl(～10.61%)-H2O(298.15K)的相平衡及其固相化合物

０引言研究发现，卤化物KX与ZnX２组成的复盐化合物是一种良好的激光基质材料犤１犦，在掺杂了稀土离子的这些化合物中已经实现了低温或室温下的激光输出犤２，３犦。在卤化物中，氯化物的发光强度又大于氟化物犤４犦。因此，我们以KCl与ZnCl２为研究对象，通过盐酸溶液中的相化学反应来了解它们之间可能形成新化合物的种类和溶液中的反应行为。本文对KCl与ZnCl２在２５℃１１％的盐酸－水四元体系中的相平衡关系进行了研究，并从体系中发现并得到了未见文献报道的５∶４型新化合物５KCl·４ZnCl２·３H２O。１实验部分１．１药品及…     

Determination of hydrochloric acid in organic solutions by gas chromatography

Summary A method is described for the determination of small quantities of hydrochloric acid in two chlorinated organic solvents (CHCl₃ and CCl₄). An excess of gaseous ethylene oxide is added to a liquid sample; the 2-chloroethanol formed is then analyzed by gas chromatography. The procedure is simpler and more sensitive in comparison with other conventional methods. It can be modified for other organic solvents.D.G.R.C.S.T. grant.     

聚氯乙烯—丁腈橡胶—氯丁橡胶三元共混物的研究

测定了聚氯乙烯（ＰＶＣ）－丁脯橡胶（ＮＢＲ－２９）－氯丁橡胶（ＣＲ）三元共混物的冲击性能和应力－应变行为，用动态力分析、扫描电和透射电镜研究了共混物的相容性和形态结构。结果表明，ＮＢＲ－２９对ＰＶＣ，ＣＲ有良好的增容作用，三元共混物是部分相容的二相体系，具有良好的抗冲击性能。     

The Effects of M2O3 on Stabilizing Monocopper over the Surface of Cu-ZnO-M2O3 Catalysts for Mathanol Synthesis

The effects of M₃O₃ (M = Al, Sc etc.) in Cu-ZnO-M₂O₃ catalysts on methanol synthesis at low pressure were studied with ESR, XPS and TPR spectroscopy. The results of ESR showed that the generation of monovalent cationic defects was because the valence state and electronic charge on the ZnO lattice lost their balance as M³⁺ doped into ZnO. The induced effect by Sc³⁺ is stronger than that by Al³⁺. The results of XPS and TPR indicated that the amount and stabilization of Cu⁺ on the surface of reduced copper-based catalyst and its catalytic activity were affected by the monovalent cationic defects on the surface of ZnO.     

硫化物纳米级粒子化膜的形成与气相性质的影响

采用偏振光反光度、紫外及可见光谱、电子显微镜形貌观察、粒子大小测定及电子衍射等方法加以系统研究硫化锌纳米级粒子化膜的制备与气相性质的影响．     

红外光谱法观察二茂镧系氯化物与氧及水蒸气的反应

用实时红外光谱法在特制的收池中分别观察了一些二茂镧系氯化物Ｃｐ２ＬｎＣｌ（Ｃｐ＝Ｃ５Ｈ５，Ｌｎ＝Ｈｏ，Ｇｄ，Ｌｕ）和Ｃｐ＇Ｌｕ（Ｃｐ＝Ｃ５Ｈ４ＣＨ２ＯＣＨ３）与干燥氧气及水蒸气的反应，结果证实这些二茂镧系配合物在室温干燥氧气氛中很稳定，但在水蒸气中很快水蒸气的反应，结果证实这些二茂镧系配合物在室温干燥氧气氛中很稳定，但在水蒸气中很快水解。从水解反应的最初始阶段和较后期采得的红外光谱提示可能存在...     

Aluminum Lon Removal from Monoaluminum Ovotransferrin by Pyrophosphate

The rates at which aluminum was removed from the N- and C-terminal monoaluminum ovotransferrins by pyrophosphate were evaluated by UV difference spectra in 0.01 mol/L Hepes, pH=7.4 and at 37℃. Pesudo first-order rate constants as a function of pyrophosphate concentration were measured. The results indicate that the pathways of aluminum removal are different. For the N-terminal binding site, aluminum removal follows simple saturation kinetics, while the removal of aluminum from the C-terminal binding site reverts to the combination of saturation and first-order kinetics. The saturation component is consistent with a rate-limiting conformational change in the protein as has been reported. We propose that the first-order kinetics mechanism is attributed to a pre-equilibrium process. The rate constants of saturation kinetics are accelerated from both terminals with the addition of 0.1 mol/L chloride to the monoaluminum ovotransferrin solutions, whereas the rates of the first-order kinetics are decreased for the C-terminal binding site. The effect of chloride ionic strength causes a continuing increase on kobs for the N- and C-terminal binding sites. Moreover, the kinetics behavior of the N-terminal is more easily affected by chloride than that of the C-terminal. In the experiment presumably the N-terminal site is apparently kinetically more labile than the C-terminal site.     

Application of self-assembly for replacing chromate in corrosion protection of zinc

Due to the toxic and carcinogenic properties of hexavalent chromium ion, the corrosion protection with chromating technique needs replacement. Several environmentally friendly alternative metal pretreatments have already been proposed. One of these methods is the application of self-assembling molecules to form mono- or multilayers on the metal surfaces. These layers can prevent metal dissolution due to their dense and stable structure. The objective of our studies was to protect zinc surface against corrosion, with a thin phosphonate layer. Aqueous solutions of diphosphonic acid with different alkyl chain lengths were applied with different treatment times. The layer formation, stability, and corrosion protection of these films were monitored by electrochemical impedance spectroscopy and the effect of 1,5-diphosphono-pentane (DPP) on zinc was studied by polarization curves. The wetting properties were determined by static contact angle measurement. 1,5-Diphosphono-pentane forms a thin layer, with a pronounced protective ability in neutral aqueous solutions. The application of self-assembling molecules can be a promising method to replace the chromating technique on zinc surface.     

健儿三宝冲剂治疗儿童钙,铁,锌缺乏症164例临床观察

用健儿三宝冲剂治疗的儿童钙，铁，锌缺乏症，经临床观察，取得了较好的疗效。