ICP-AES法测定钛基复合材料中的Al、Mo、B的研究

本文采用ＩＣＰ－ＡＥＳ法对钛基复合材料中的合金元素Ａｌ、Ｍｏ、Ｂ的测定进行研究,着重进行了基体元素对待测元素Ａｌ、Ｍｏ、Ｂ的干扰试验及各元素在测定浓度范围内线性相关性,进行了酸度试验,测定了钛基复合材料中上述三元素的含量,得到了较好的精密度和准确度。     

碱溶ICP—AES法同时测定AISi／SiC复合材料中的高含量硅和低含量？…

本文采用碱溶ＩＣＰ－ＡＥＳ法对ＡＩＳｉ／ＳｉＣ复合材料中的高含量硅和低含量镁、钛、铁的测定进行研究,着重进行基体元素铝及特测定元素硅、镁、钛、铁之间的干扰试验,进行了碱度试验和酸度试验,测定和ＡＩＳｉ／ＳｉＣ复合材料中的硅、镁、钛、铁含量,得到了较好的精密度和准确度。方法简便可靠,可获得满意的分析结果。     

碱溶ICP-AES法同时测定AlSi/SiC复合材料中的高含量硅和低含量镁、钛、铁

本文采用碱溶ICP-AES法对AlSi/SiC复合材料中的高含量硅和低含量镁、钛、铁的测定进行研究,着重进行基体元素铝及待测定元素硅、镁、钛、铁之间的干扰试验,进行了碱度试验和酸度试验,测定了AlSi/SiC复合材料中的硅、镁、钛、铁含量,得到了较好的精密度和准确度.方法简便可靠,可获得满意的分析结果.     

ICP-AES法测定镍基、铁镍基高温合金与结构钢中的微量硼

本文采用ＩＣＰ－ＡＥＳ法对镍基、铁镍基高温合金与结构中微量硼元素的测定进行了研究,着重考察了镍基ＤＺ１２５合金,铁镍基ＧＨ４１６９合金和结构钢的基体与合金元素对硼含量测定的影响,采用了分步沉淀分离方法,消除了铁（基体）、钨和铌,钽（合金中共存元素）对硼的干扰,测定了样品中微量硼,取得了满意的结果。     

ICP-AES法测定铁钕合金中主量元素钕及7种杂质元素的研究

用ICP－AES法同时测定了铁钕合金中主量元素钕及Al、Si、Mn、Cr、Mg、Zr、Ca等7种杂质元素。研究了基体元素铁、主量元素钕对杂质元素的光谱干扰,选择了合适的分析线和内标线,测定了分析方法的检出限,回收率为87％－113％。方法准确、快速、简便,结果令人满意。     

ICP-AES测定铁钕合金中Ho、Er、Tb、Tm、Cu、Mo、Nb等7种杂质元素

采用ICP－AES法同时测定了铁钕合金中Ho、Er、Tb、Tm、Cu、Mo、Nb等7种杂质元素。研究了基体元素铁、主量元素钕、镝、钴、硼对杂质元素的光谱干扰情况；选择了合适的分析线；测定了分析方法的检出限。加入回收率为90．0％－108．0％。方法准确、快速、简便。     

高纯La-Ni-Al合金成分及杂质元素的分析方法研究

叙述了镧－镍－铝（La-Ni-Al)合金分镍、铝及微量杂质元素锌、铁、锰、镁、硅、铜和钙的ICP－AES测定方法。样品以HNO3（1＋1）溶解,稀释后直接测定主量元素镍和铝;用基体匹配法补偿基体效应测定其他杂质元素。各元素回收率在95％－106％,相对标准偏差优于5％。     

发射光谱法同时测定钛基复合材料中的镍铁钼锰和硼的研究

研究了用碳粉、碳酸钙、氧化铜和氧化铍作缓冲剂同时测定钛基复合材料中的镍、铁、钼、锰和硼的发射光谱法,选择铍作内标线,不需分离、不需化学处理,直接压样于杯形的石墨电极中,具有简便、快速、准确。对测定条件、干扰因素进行了研究,从而建立测定镍、铁、钼、锰和硼的新方法。镍、铁、钼、锰和硼的分析线分别为300.36,248.33,315.82,260.57和249.68 nm,内标线选择为铍的298.61 nm,镍、铁、钼、锰和硼的线性范围分别为0.003%～0.30%;0.001%～0.20%;0.003%～0.30%;0.001%～0.20%;0.001%～0.20%。镍、铁、钼、锰和硼的检测限分别0.003%,0.001%,0.003%,0.001%,0.001%,其回收率在95.80%～104.8%范围内,当n=9时,相对标准偏差RSD均小于5%。用于样品的测定取得了满意的结果。     

ICP-AES法测定镍基高温合金中16个元素的方法研究

该方法采用ICP-AES法对镍基高温合金中16个元素进行了测定,系统研究了基体元素和共存元素对分析元素谱线的光谱干扰情况,进行了分析线的选择,测定了方法检出限,通过准确度试验和精密度试验,表明该方法准确、可靠、简便、快速。     

ICP－AES法测定钨合金中镍、钴、铁、锰时酸度的影响

本文研究了用电感耦合等离子体发射光谱技术测定钨合金中镍、钴、铁、锰含量的方法及酸度对测量结果的影响。用氢氟酸及硝酸处理试样，并加入适量盐酸。实验研究了测量值随氯离子浓度增大而下降的变化曲线，找出了测量不同元素的最佳测定条件，测量结果同标准值比较，误差较小。     

Growth kinetics and precipitation phenomena in undercooled Nd–Fe–B melts with Ti and C additions

The microstructure and the solidification kinetics of stoichiometric Nd–Fe–B alloy with Ti and C additions were investigated using the electromagnetic levitation technique. In situ temperature–time characteristics were carried out. A strong reduction of the growth velocity of the Nd₂Fe₁₄B phase was observed in the Nd–Fe–B–Ti–C alloy compared to the addition-less Nd–Fe–B alloy. The undercoolability of the melt depends on the alloy composition. Moreover, at high TiC contents, the maximum undercooling level is strongly reduced turning to low cooling rates. The TiC solution and its formation were studied in overheated and undercooled samples, respectively after subsequent quenching. The cooling rate prior to solidification influences drastically the morphology of the TiC precipitates which affects strongly the nucleation of the properitectic γ-Fe phase in the undercooled stage.     

Reactive plasma cladding of TiC/Fe cermet coating using asphalt as a carbonaceous precursor

A new process of preparing Ti-Fe-C composites powder for reactive plasma cladding, precursor carbonization-composition process, was developed. TiC/Fe cermet coatings were synthesized by reactive plasma cladding of the composite powder. XRD and SEM were employed to analyze the phase composition and microstructure of the composite powder and coating. The hardness and wear resistance of the coating was tested. Results show that: The compound powder prepared by precursor carbonization-composition process has very tight structure, which can avert the question of raw powder breaking-up in cladding process. The TiC/Fe cermet coating by reactive plasma cladding consists of alternate, laminated layers as following: the layers in which the round nanoscale TiC particles are dispersed within the α-Fe matrix and the layers of TiC accumulation. The TiC/Fe cermet coating by reactive plasma cladding shows superior hardness and wear resistance: The surface hardness of the TiC/Fe cermet coating is 68 ± 6 (HR30 N). In the same fretting conditions, the wear resistance of Ni60 coating is twelve times than that of the TiC/Fe cermet coating.     

Energy‐dispersive x‐ray fluorescence analysis of modern coloured glasses from Marinha Grande (Portugal)

The elemental composition (K, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Sr, Ba, Nd and Pb) of modern coloured glasses was obtained by energy‐dispersive x‐ray fluorescence (EDXRF) spectrometry. This non‐destructive technique is frequently used in the analysis of historical glass objects. Two reference glasses were also measured to assess the overall accuracy of the EDXRF method. Reference and unknown glasses were analysed without any preparation. The coloured glass samples studied belong to the Glass Museum of Marinha Grande and were chosen from two distinct collections, which were characterized by the different concentrations of some elements (K, Ti, Cr, Mn, Fe, Ba and Pb). The determined major elements allowed the identification of two raw materials used in glass manufacture, sand and lime. Multivariate statistical analysis, namely principal component extraction, simplified the identification of some of the colouring chemical elements, associating them with the different colours of the glass objects. Copyright © 2003 John Wiley & Sons, Ltd.     

ICP-AES同时测定铝合金中Fe,Si,Cu,Mg,Mn,Ni,Zn,Ti,Cr,Sr等杂质元素

本文通过基体干扰和操作条件的试验研究，分别用基体匹配法和干扰系数法校正基体干扰和待测元素间的干扰，建立了以氢氧化钠溶样，ICP－AES同时测定铝合金中铁、锰、铜、锌、镁、钛、硅、镍、铬、锶等杂质元素的方法。方法快速、简便、可靠，回收率93％－102％，适用于进出口铝合金的快速检验。     

Ti, C, N在α-Fe基中的合金化效应及对键合性质的影响

基于第一性原理赝势平面波方法研究了合金元素Ti, C, N对α-Fe基电子结构及键合性质的影响, 计算了含Ti, C, N的Fe基固溶体的总能量、结合能, 分析了态密度、电荷布居数、交叠布居数和电荷密度, 从理论上解释了在Fe基中固溶Ti, C, N后其性能改善的原因. 结果表明, 随着Fe基固溶体中Ti(0-12.5 at%), C(0-11.11 at%), N(0-11.11 at%)含量增加, 结合能略有增加; Ti, C, N的固溶使各Fe基固溶体在费米能级处强烈成键, 结合能力增强, 并且在费米能级附近出现赝能隙, 表明固溶体中金属键与共价键共存; 随着Ti, C, N含量的增加, C, N分别与Ti, Fe之间的共价键结合强度加强, 部分C, N原子会与Ti原子结合形成TiC, TiN颗粒, 起到沉积相颗粒强韧化作用.     

Laser properties of yag: Nd,Cr, Ce

Summary Transient absorption of a long lifetime ( 20 s) of YAG: Nd is typical of pure material. It is the main reason of thermal deformation of the laser rods accompanied with power decreases at higher CW input. It may be prevented by an admixture of Fe, Ti or Cr. Using a small admixture ( 10^–3 wt.%) of Ti or Cr the energy transfer among Nd ions and the gain coefficient may be increased. Cr in a higher concentration absorbs the pumping light and serves as earlier described coactivator (sensitizer) only. Fe impurity fully prevents any increase of the gain of YAG: Nd containing Ti or Cr and causes slow but irreversible degradation of the active parameters. Ce favourably modifies properties of YAG: Nd, Cr. YAG: Nd, Cr, Ce free of iron impurity is advisable active material for powerfull CW lasers.     

Microstructure and magnetic properties of NdFeB alloys by co-doping alnico elements

Elements of alnico 8 are added into Nd-Fe-B alloys fabricated by rapid solidification method. It is observed that the magnetic properties at high temperature improved by small addition of alnico elements. The Curie temperature of the alloys increased from 580 K for standard alloy to 639 K by 20% addition of alnico 8 elements. The spin reorientation temperature decreased from 133 K to 104 K. The TEM analysis showed that elements of alnico 8 refine the microstructure of Nd-Fe-B ribbons. The STEM analysis confirmed the heterogeneous distribution of Nd, Fe, Cu, Al, Ni and homogeneous distribution of Ti, Nb and Co. The boundaries of nano grains contain more than 70% ferromagnetic elements, ensuring strong inter-grain coupling among the grains.