复合合金化对AZ91镁合金铸态组织的影响

利用光学显微镜、扫描电镜和X射线衍射仪研究了0.5?、0.2?、0.2%Sr(质量分数,下同)复合合金化对AZ91合金铸态组织影响。结果表明,0.5?、0.2?、0.2%Sr复合加入可以显著细化合金的铸态组织,0.5?、0.2?、0.2%Sr同时加入,其细化效果优于0.5?和0.2?或0.5?和0.2%Sr的复合加入,并且在组织中出现针状或杆状的Al4Ce新相。     

Study on the anodic film formation process of AZ91D magnesium alloy

The formation of anodic film of AZ91D magnesium alloy has been investigated by means of electrochemical impedance spectroscopy (EIS), cyclic voltammetry, anodic polarization curve, current-time transients and SEM technique. The results show that, under our experimental conditions, the formation of AZ91D anodic film follows the mechanism of 3D nucleation with diffusion controlled growth. With the increase of applied anodizing potential, the nucleation type of anodic film changes from progressive to instantaneous. The results also show that the initially formed anodized film is threadlike and porous, and high potential is essential for the formation of good anodic film with excellent properties.     

镁渣膨胀性机理试验研究

通过镁渣形成过程、组成、粉化、颗粒分析和安定性试验,研究了镁渣产生体积膨胀性和膨胀滞后性的机理,提出了减轻或消除其膨胀性和膨胀滞后性危害的方法和措施,为镁渣在建筑、交通、水利等工程领域中的应用提供理论依据和指导。     

关于生产精制元明粉的探讨

介绍了以山西运城南风自产芒硝为原料生产精制元明粉的几种工艺,以及国内外精制元明粉的市场及生产状况.精制工艺包括化学除杂法、原料优选法、重结晶法.结果表明,精制元明粉的生产过程实质是一个除杂、提纯过程：对于钙离子含量高的原料,可采用化学除杂法;对于氯离子含量高的原料,可采用氯离子富集法、冷冻法或洗涤法;镁离子较难去除,可采用水硝洗涤、冷冻法.     

不同形貌氢氧化镁的化学合成及影响因素

对不同形貌氢氧化镁的化学合成及外部生长环境进行了综述。尤其对影响氢氧化镁结晶性能和形貌起关键作用的因素，如碱性沉淀剂的选择、合成温度的确定、不同镁盐的影响、碱和镁盐的初始浓度及配比、水热处理、反应物的混合方式、晶形控制剂的加入等，进行了详细的阐述。     

Effect of cation exchange on the distribution and movement of cations in soils with variable charge. I. Effect of lime on potassium and magnesium exchange equilibria

The influence of Ca(OH)₂ on K and Mg exchange equilibria in three New Zealand soils was studied. Calcium hydroxide was mixed with each soil to raise the pH to about 6 or 7. For each Ca(OH)₂ treatment, K and Mg exchange isotherms were determined, from which the equilibrium activity ratios were derived. Exchange coefficients and solution activity ratios were calculated according to the Gapon convention.The addition of Ca(OH)₂ produced varying effects in the Gapon exchange coefficient for both K and Mg. The magnitude and direction of change in the exchange coefficient were related to the cation initially dominating the exchange sites, rate of Ca(OH)₂ addition, soil colloids contributing to the CEC and specific interactions of Ca with these soil colloids.Addition of Ca(OH)₂ reduced the equilibrium activity ratio of all soils. Changes in the bonding strength of K and Mg with increasing CEC were suggested as a possible mechanism for this decrease.     

不同品种磷肥在土壤中的退化研究

对钙镁磷肥（FMP）、过磷酸钙（SSP）和部分酸化磷肥（PAPR）在河南郑州西岗沙土和河南西华县潮土中的退化情况进行了研究。     

Lanthanum-Magnesium and Lanthanum-Manganese Donor-Acceptor-Codoped Semiconducting Barium Titanate

BaTiO₃ powder doped with La donor and codoped with Mn or Mg acceptor was sintered at 1350°C/1 h in air. For Ladoped BaTiO₃, the room-temperature resistivity decreased to a minimum at [La³⁺] ∼ 0.15 mol%. For La-Mn-codoped BaTiO₃, the minimum resistivity occurred at [La³⁺] - 2[Mn²⁺] ∼ 0.15 mol%. When the ceramic was changed to a fine-grained insulator by high donor doping ([La³⁺] >0.15 mol%), its semiconductivity was restored, and the relatively homogeneous, coarse-grained microstructure recurred by codoping with either Mg or Mn acceptor, with the transition at [La³⁺] - 2[Mg²⁺] = 0.15 mol% or [La³⁺] - 2[Mn²⁺] = 0.15 mol%. The analogy of a compensation effect between La-Mn- and La-Mg-codoped BaTiO₃ suggested that Mn acceptor added to BaTiO₃ exists as Mn²⁺ ion in the bulk grain region; its influence on the positive temperature coefficient of resistivity behavior is then discussed.     

氢氧化镁和氧化镁中酸不溶物的研究

产硝后的高镁卤水和硫氢化钡溶液进行反应，生成氢氧化镁，酸不溶物在0．3％（质量分数）左右，但将其煅烧成氧化镁后，酸不溶物高达1．2％-2．5％（质量分数），二者酸不溶物远不成比例关系。通过对样品在分析中穿滤对比、硫酸法测定酸不溶物、碘量法测定硫化物试验，确定在生产过程中，硫氢化钡被氢氧化镁吸附，经过高温煅烧，硫氢化钡被氧化成硫酸钡，成为氧化镁中的酸不溶物，这就是氧化镁和氢氧化镁中酸不溶物不成比例的主要原因。     

氢氧化镁中微量元素硼硅铝的测定

以盐湖高镁卤水为原料生产的氢氧化镁产品纯度不高,含有部分无机杂质离子,为提高产品质量,改进产品性能,通过实验确定了氢氧化镁中微量元素硼、硅、铝的分光光度测定方法。此方法准确度与精密度较高,测定样品中的硼、硅、铝加标回收率分别为98.3%-101.5%,96.0%-99.3%,96.5%-97.3%,相对标准偏差（n=6）分别为2.06%,2.27%,2.39%,快速、简便、成本低,可作为企业生产的常规检测方法使用。