X射线荧光光谱法同时测定石灰石中主次痕量组分

采用熔融玻璃片和粉末压片法制样,选用标准样品,以经验α系数和散射线内标法校正元素谱线重叠干扰和基体效应,用ZSX PrimusⅡX射线荧光光谱仪对石灰石样品中CaO、Na2O、MgO、Al2O3、SiO2、K2O、TFe2O3、P2O5、TiO2、MnO和S等主次痕量组分进行测定,分析结果与标准值和化学值相符,12次测定的相对标准偏差小于10%。     

X射线荧光光谱法快速分析镁质耐火材料中硅铝铁钛钙镁

采用X射线荧光光谱法快速测定镁质耐火材料（包括原料镁砂及其制品镁砖）中的SiO₂、Al₂O₃、Fe₂O₃、TiO₂、CaO、MgO等6种组分。利用粉末直接压片法制取试样,确定仪器最佳参数,系列标样建立工作曲线,经验系数法对基体效应进行校正。对于主次组分,方法精密度低于5%（n=10）。方法用于实际样品的测定,结果与实验室化学法和其他单位的X射线荧光光谱法相符。方法适用于厂矿企业大批量生产的镁质耐火材料化学组成分析。     

黄土抗震陷变形的酸改性方法及其微观结构分析

低黏性粉质黄土的架空弱胶结微结构,导致这种黄土在动荷载作用下呈现出强度低、震陷变形大的现象,为黄土场地地基处理提出了挑战性的技术难题。黄土结构改性是通过改变其微观结构,达到有效降低震陷变形和湿陷性等为目的。本文采用酸改性方法处理黄土,即通过加入有较强分散和胶结效果的硼化合物作为主要改性物质;加入轻质碳酸钙等填料,调整原状土的颗粒粒径级配;以磷酸稀释液调解土的pH值。对改性土样进行震陷等试验测试对比,确定最佳配方,同时分析改性前后微观结构和能谱的变化。结果表明,酸改性方法能有效改善黄土的微观结构,使得土样的震陷变形系数明显降低。并且所添加的改性原料无毒,不会对土层产生污染。     

铁尾矿粉热压成型类石板试验

探寻废弃铁尾矿粉再生利用的有效途径,将其制备成为消耗量大、附加值高的建筑型材是铁尾矿粉热压成型类石板材的根本目的。根据微晶玻璃的形成原理,使用鞍山式铁尾矿粉配制4种不同类型的混合粉料,4种配方中共同含有的主要化学成分为Al2O3、MgCO3、CaCO3、BaCO3、Na2CO3,分别在温度900～1 000℃、压力10～20MPa、升温时间5～8min、保温时间10～30min条件下在液压加压中频加热炉上进行热压成型试验,分别在室温和炉温自然冷却条件下冷却至室温。热压成型试验结果表明:合适的添加剂掺量和温度以及压力控制能够实现铁尾矿粉类石板的热压成型,最佳的热压成型温度范围为950～1 000℃,试样硬度与压力呈非线性关系,但当压力超过15MPa后试样的硬度明显提高。热压成型试样的最大硬度为HRC37。     

High pressure behaviour of lead feldspar (PbAl2Si2O8)

An in situ high pressure powder diffraction study, using high-brilliance synchrotron radiation, on lead feldspar (PbAl₂Si₂O₈) was performed. Two samples, with Q _od=0.68 and 0.76, were loaded in a diamond anvil cell and were compressed up to 11 GPa. Up to P=7.1 GPa the only phase present is lead feldspar. In the range 7.1–9.4 GPa sudden changes in the position of the reflections suggest the transformation of lead feldspar to a new phase (probably feldspar-like). The absence of split that would be compatible with triclinic symmetry rules out the monoclinic-triclinic transition, that was reported for the structurally similar strontium feldspar. At P>9.4 GPa some new extra reflections not indexable in the feldspar cell are present as well. During decompression the lead feldspar was the only phase present at P<6 GPa. Peak enlargement was observed with pressure, probably preliminary to amorphization. However almost complete amorphization was observed only after fortuitous shock compression at ∼18 GPa; the crystallinity was recovered at room pressure after decompression. The bulk modulus for lead feldspar was K=71.0(9) and 67.6(1.2) GPa for the two samples, in the range reported for feldspars. The cell parameters show a compression pattern which is similar to that observed in anorthite, with Δa/a ₀>Δc/c ₀>Δb/b ₀; comparison with the high temperature behaviour shows that for lead feldspar the strain tensor with pressure is more isotropic and the deformation along a is less prominent. A turnover in the behaviour of the β angle with pressure suggests a change in the compression behaviour at P∼2 GPa. Rietveld refinement of the Pb coordinates was performed in a series of spectra with pressure ranging from 0.6 to 6.5 GPa. The combined analysis of cell parameters and Pb coordinates with pressure showed that the compression of the structure is mainly achieved by an approach of Pb atoms along a *. Received: 21 July 1998 / Revised, accepted: 13 October 1998     

Cation partitioning versus temperature in (Mg0.70Fe0.23)Al1.97O4 synthetic spinel by in situ neutron powder diffraction

Neutron powder diffraction experiments in the temperature range 300–1770 K were performed at BENSC, Berlin, Germany, on synthetic (Mg_0.70Fe_0.23) Al_1.97O₄. The cation partitioning over the crystallographic tetrahedral and octahedral sites was determined as a function of temperature through joint Rietveld refinements and advanced minimization techniques. The thermal expansion coefficients of the lattice parameter and inter-atomic bond lengths were also obtained from the full-profile structure refinements. The behaviour of the polyhedral bond-lengths, especially the T−O distances, and of the cell constant upon heating, clearly indicate that the interdiffusion of tetrahedral and octahedral Mg/Al cations starts at about 950 K. This result is straightforwardly supported by the direct analysis of the neutron site scattering factors: Fe always retains tetrahedral coordination at all temperatures, and the cation rearrangement is entirely due to Mg and Al diffusion. Received: 18 November 1997 / Revised, accepted: 23 August 1998     

金刚石微粉质量的评定

从用户和生产厂家的观点阐述如何评定金刚石微粉的质量。着重论述根据金刚石微粉的粒度、颗粒形状、锐利性、抗磨耗性和强度来评定金刚石微粉的质量     

浅谈粉碎洗涤盐生产中的技术改造

对粉碎洗涤盐的技改过程、技改方向进行了总结并列举大量实验数据 ,说明技改前后粉洗盐质量变化及成功经验。同时对粉洗盐粒度存在的问题进行了分析并提出建议     

Rapid Determination of Trace and Ultra Trace Level Elements in Diverse Silicate Rocks in Pressed Powder Pellet Targets by LA‐ICP‐MS using a Matrix‐Independent Protocol

A simple, single sample preparation involving pressed rock powder pellets was utilised to determine the trace and ultra trace abundances of petrogenetically important elements including high field‐strength elements and REEs by laser ablation‐ICP‐MS. One of the elements predetermined by XRF spectrometry served as an internal standard. The influence of sample preparation parameters (grain size, pellet compactness and amount of binding media) on analytical performance was also investigated, including sample homogeneity issues at the laser sampling scale. Line scanning with a high repetition frequency (20 Hz) and large beam diameter (200 μm) ensured ablation from a larger sample surface area, eliminating issues related to sample heterogeneity. A median grain size of about 10 μm for silicate rock powders was found to be sufficiently representative at this scale of laser sampling. Granitic rocks or samples containing resistant minerals such as zircon needed extra grinding to achieve grain sizes down to < 5 μm for better precision for elements that are concentrated in these phases. Using ¹³⁷Ba as an internal standard, reasonable accuracies within 15–20% for most of the high mass trace elements were achieved; in the case of low mass elements, it may deviate up to 40%. Precision of measurements rarely exceeded 15% RSD.     

超细粉末材料粒度测试技术研究

随着科学技术的发展,越来越多的细粒级粉末产品成为社会需求。如何便捷、准确地获得这些超细粉料的粒度数据,也就成了工艺矿物学工作者的一个课题。粒度测试分析中存在一些仍未解决的问题,例如采用不同的测试方法得到不同的粒度数据、取样的代表性和制样的合理性等。对于超细粉料,除了上述普通物料粒度测试中存在的问题之外,还会出现一些新问题,例如团聚现象的普遍性及其给各种测试方法带来的技术难题。近年来中国颗粒学会、国家有色金属工业局和冶金工业局等单位在这些方面做了许多有益探索,但在一些难题面前仍然显得软弱无力,主要…