电感耦合等离子体原子发射光谱(ICP-AES)法测定高铁土壤中的铝

采用碱熔再酸化分解样品,电感耦合等离子体原子发射光谱(ICP-AES)法测定高铁土壤中的铝(Al)元素。通过逐级扩大线性范围的方式,选取测定高含量Al的合适谱线;在标准中逐级加入铁基体,考察了铁基体浓度从20μg/mL到80μg/mL时对测定Al的各谱线的干扰情况。用ICP-AES法对国家标准物质GSS-1、GSS-2、GSS-3、GSS-4、GSS-5进行测定,测定值与认定值的相对误差(RE)在-0.37%～0.31%,相对标准偏差(RSD,n=5)为0.26%～0.75%,获得了满意结果。     

电感耦合等离子体原子发射光谱(ICP-AES)法测定高铁土壤中的铝

采用碱熔再酸化分解样品,电感耦合等离子体原子发射光谱(ICP-AES)法测定高铁土壤中的铝(Al)元素。通过逐级扩大线性范围的方式,选取测定高含量Al的合适谱线;在标准中逐级加入铁基体,考察了铁基体浓度从20μg/mL到80μg/mL时对测定Al的各谱线的干扰情况。用ICP-AES法对国家标准物质GSS-1、GSS-2、GSS-3、GSS-4、GSS-5进行测定,测定值与认定值的相对误差(RE)在-0.37%～0.31%,相对标准偏差(RSD,n=5)为0.26%～0.75%,获得了满意结果。     

ICP-AES测定废Al2O3基催化剂中Pt、Pd

研究了废Al2O3基催化剂中Pt,Pd的ICP－AES测定新方法。以王水溶解样品，在HCl(5 95)介质中，用工作曲线法对废Al2O3基催化剂中的Pt,Pd直接进行测定，不需进行基体匹配。方法的检出限分别为：Pt 0.1μg/mL，P 0.045μg／mL；样品的加标回收率为Pt 95.2%-105.5%,Pd 95.3%-100.6%;RSD(n=6)均＜9％。     

碱熔–ICP–AES法测定铅精矿中11种主次元素

建立碱熔–ICP–AES快速测定铅精矿中11种主次元素的方法。采用NaOH+Na_2O_2组合碱熔分解样品,被测元素的分析谱线分别为Pb 220.353,Sn 189.989,As 189.042,Zn 206.200,Bi 223.061,Mg 279.533,Si 288.158,Al308.215,Cu 324.754,Fe 259.940,Ag 328.068。被测元素的质量浓度在0～10μg/mL范围内与发射强度呈良好的线性关系,线性相关系数均大于0.999,方法检出限为0.006～0.028μg/mL。用该方法对铅精矿国家标准物质进行测定,测定结果的相对标准偏差为0.40%～9.94%(n=7),测定值与标准值基本一致。该方法检测快速,结果准确,适用于铅精矿中金属元素的常规检测。     

ICP–AES法测定低合金钢中的微量硼

采用电感耦合等离子体发射光谱法(ICP–AES)测定低合金钢中硼元素的含量。采用密闭微波消解法对样品进行溶解,考察了铁基体元素和共存元素对硼元素测定的影响,确定了硼元素的分析线为208.959 nm,通过基体匹配消除基体的影响。硼的质量浓度在0~5.00μg/m L范围内与谱线强度呈良好的线性,相关系数r2=0.999 9,方法检出限为0.004μg/m L,加标回收率为96%~103%,测定结果的相对标准偏差为1.5%~2.9%(n=8)。该方法具有较高的灵敏度和准确度,满足低合金钢中硼元素的分析要求。     

ICP–AES法测定稀土硅铁球化剂和孕育剂中钙、镁、铝、锰、镧、铈

建立了电感耦合等离子体原子发射光谱法(ICP–AES)测定稀土硅铁球化剂和孕育剂中Ca,Mg,Al,Mn,La,Ce等元素含量的方法。通过基体匹配消除了铁基体的干扰,Ca,Mg,Al,Mn,La,Ce的分析谱线分别为317.933,279.553,394.401,257.610,333.749,456.236 nm。各元素标准曲线的线性相关系数均在0.999以上,检出限在0.000 1%~0.000 4%之间。方法的加标回收率为99.4%~102.8%,测定结果的相对标准偏差均小于3%(n=11)。用该方法测定标准样品,测定结果与认证值相吻合。该法适用于稀土硅铁球化剂和孕育剂中钙、镁、铝、锰、镧、铈的测定。     

ICP—AES法测定陶瓷材料氮化硅中十三种杂质元素

采用超声波雾化进样,ICP—AES法对氮化硅中十三种杂质元素的测定进行了试验研究。取样量1g时,铝、钙、钴、铬、铜,铒、铁、镁、锰,镍、钛、钒和锌的测定范围为0.1～12.8μg·g~(-1),回收率为93％～110％,RSD(n=8)为0.8％～3.2％。     

粮食中微量硼的极谱测定

在pH 4.0的邻苯二甲酸氢钾溶液中,硼与铍试剂(Ⅲ)生成配合物于电位-0.45V(vs.SCE)能产生一灵敏稳定的极谱波,波形尖锐,波高与硼浓度在0.005～0.5μg·ml~(-1)范围内呈良好线性关系,检出限达0.001μg·ml~(-1)。该方法用于粮食中微量硼的测定,回收率在98％～104％,与ICP—AES的分析结果一致。     

电感耦合等离子体原子发射光谱法同时测定锌冶炼酸浸渣中12种元素

建立电感耦合等离子体原子发射光谱(ICP–AES)同时测定锌冶炼酸浸渣中铅、铜、铁、镉、钴、镍、锑、钙、镁、铝、砷、锰12种元素的方法。样品采用硝酸–盐酸–氢氟酸–高氯酸四酸溶解,以体积分数为10%的盐酸–硝酸混合溶液为介质,在优化的实验条件下,用电感耦合等离子体原子发射光谱法测定各元素含量。铜、铅、铁、镉、钴、镍、锑的质量浓度在0.10～50μg/mL范围内,钙、镁、铝、砷、锰的质量浓度在0.10～10μg/mL范围内与光谱强度呈良好的线性关系,相关系数均大于0.999,方法检出限为0.002 1～0.025 5μg/mL。测定结果的相对标准偏差为0.012%～1.87%(n=6),样品加标回收率为99.0%～100.3%。采用该方法测定锌精矿成分分析标准物质和实验室内控样品,测定值与参考值基本一致,相对误差为0.00～3.33%。该方法简单、快速,具有较高的准确度和精密度,适用于锌冶炼酸浸渣样品中多元素同时测定,在锌冶炼行业具有重要的应用价值。     

ICP–AES法测定锑铍芯块中铅、铁、锰和镁

建立电感耦合等离子体原子发射光谱(ICP–AES)测定锑铍芯块中铅、铁、锰和镁杂质元素的方法。对溶液酸度的选择、光谱和基体干扰等进行了试验和讨论,在优化仪器工作参数的条件下,通过基体匹配,有效消除了基体干扰的影响。铅、铁、锰、镁的质量浓度在0.05~10.0μg/mL范围内与其光谱强度呈良好的线性关系,线性相关系数大于0.999。铅、铁、锰、镁的检出限在0.5~5.3μg/L之间,测定结果的相对标准偏差为0.9%~2.9%(n=7),加标回收率为92%~106%。电感耦合等离子体原子发射光谱法与原子吸收光谱法对照,测定结果相符合。该方法准确可靠,可用于锑铍芯块中铅、铁、锰和镁杂质元素的测定。     

聚合物在高压下的结构、形态和性能（下）

聚合物在高压下的结构、形态和性能（下）张雄伟，黄锐（成都科技大学塑料工程系，成都，６１００６５）在上篇中我们介绍了结晶性聚合物在高压下结晶的结构和形态。本篇将介绍聚合物在高压下的结晶动力学和热力学以及聚合物在高压下的退火等方面内容。２高压结晶动力学研...     

聚酰亚胺纤维

聚酰亚胺纤维具有高强度模、耐高温、耐辐射等优越的性能。在多种纺制聚酰亚胺纤维的方法中,湿纺容易制得高强高模的样品。本文主要介绍了聚酰亚胺纤维的一步法湿纺、二步法湿纺和熔融纺丝方法,并对纤维的性能进行了概述。     

超高分子量聚乙烯纤维牵伸温度研究

超高分子量聚乙烯纤维只有经过多级牵伸,才能成为高强度、高模量的高性能纤维。在牵伸工艺中涉及到牵伸温度及牵伸倍率两个工艺参数。本文从牵伸温度角度出发,采用多级牵伸得到了高性能聚乙烯纤维,利用强伸仪、DSC等表征手段,系统地研究了各级牵伸温度对超高分子量聚乙烯纤维性能影响规律,探索最佳牵伸温度组合。本项研究表明,牵伸温度直接影响最大牵伸倍率,最终影响到纤维的力学性能,采用三级牵伸可以使纤维力学性能达到较高水平,最佳温度组合为137.5℃—147.3℃—147.3℃,纤维强度32cN.dtex-1。     

Assessment of high precision,high accuracy Inductively Coupled Plasma-Optical Emission Spectroscopy to obtain concentration uncertainties less than 0.2% with variable matrix concentrations

The ability to obtain high precision, high accuracy measurements in samples with complex matrices using High Performance Inductively Coupled Plasma-Optical Emission Spectroscopy (HP-ICP-OES) was investigated. The Common Analyte Internal Standard (CAIS) procedure was incorporated into the High Performance Inductively Coupled Plasma-Optical Emission Spectroscopy method to correct for matrix-induced changes in emission intensity ratios. Matrix matching and standard addition approaches to minimize matrix-induced errors when using High Performance Inductively Coupled Plasma-Optical Emission Spectroscopy were also assessed. The High Performance Inductively Coupled Plasma-Optical Emission Spectroscopy method was tested with synthetic solutions in a variety of matrices, alloy standard reference materials and geological reference materials.     

Sb2O4 at high pressures and high temperatures

Investigations on Sb₂O₄ at high pressure and temperature have been performed up to 600 °C and up to 27.3 GPa. The so-called “high temperature” phase (β-Sb₂O₄) was obtained following pressure increase at ambient temperature and at relatively low temperatures. Thus, in contrast to previous perceptions, β-Sb₂O₄ is the modification more stable at high pressures, i.e., at low temperatures. The fact that the metastable α-form is typically obtained through the conventional way of preparation has to be attributed to kinetic effects. The pressure-induced phase transitions have been monitored by in-situ X-ray diffraction in a diamond anvil cell, and confirmed ex-situ, by X-ray diffraction at ambient conditions, following temperature decrease and decompression in large volume devices. Bulk modulus values have been derived from the pressure-induced volume changes at room temperature, and are 143 GPa for α-Sb₂O₄ and 105 GPa for the β-Sb₂O₄.     

高性能耐高温聚合物复合材料的摩擦磨损性能研究

介绍了一些常见的高性能耐高温聚合物及其复合材料的摩擦与磨损性能的研究及其新进展,包括聚四氟乙烯(PTFE)、聚醚醚酮(PEEK)、聚苯硫醚(PPS)、聚酰亚胺(PI)等.并讨论了不同种类的填料,如纤维、固体润滑剂、无机化合物以及无机纳米粒子对高性能耐高温聚合物基复合材料摩擦系数及磨损率的影响,许多研究结果表明,适量填料的加入能提高聚合物基复合材料的耐磨性能,特别是填料的协同作用对降低复合材料的摩擦系数及磨损率有更大的帮助.     

Effects of crystallinity, {001}/{101} ratio,and Au decoration on the photocatalytic activity of anatase TiO2 crystals

Anatase TiO₂ nanocrystals and sub-microcrystals with truncated octahedral bipyramidal morphologies were prepared by direct calcination of TiOF₂ precursors. The as-prepared TiO₂ samples were thoroughly characterized by X-ray diffraction, Raman spectroscopy, field-emission scanning electron microscopy, N₂ adsorption-desorption isotherms, X-ray photoelectron spectroscopy, and UV-visible diffuse spectroscopy. It was found that the crystallinity, grain size, and {001}/{101} ratio of the samples can be increased by raising the calcination temperature from 500 to 800 °C. The higher crystallinity and {001}/{101} facet ratio resulted in an increase in both aqueous and gas-phase photocatalytic activities, by inhibiting the recombination and separation of electrons and holes. After selecting two TiO₂ samples with high crystallinity and {001}/{101} ratio, Au nanoparticles were decorated on their surfaces, and the photocatalytic activity of the resulting samples under visible light illumination was studied. It was found that the visible light-induced photocatalytic activity increased by 2.6 and 4.8 times, respectively, upon Au decoration of the samples prepared by calcination of TiOF₂ at 700 and 800 °C.     

An Enzyme Electrode Based on the Covalently Binding of Horseradish Peroxidase to a Self-assembling Monolayer Modified Gold Electrode

Tledetenhinationofl1ydrogenperoxideisofprachcalimportanceinchemical,biologi-cal,clinical,andmanyotllerfields.EnZylneelectrodeshavebeenutilizedasil1esensorforhydrogenperoxideduetoitssensitivity,reliability,andoPerahonalsimplicityl-ll.Manymethodshavebeenusedtoiminobilizehorseradishperoxidasegu)onelec-trodessucl1asadsorphononpretreatedcarbonorgupl1iteeIectrode'-',cross-liIthingwithpolymer"'andmikingwih1gnplhteoilPaste"',t.Inil1epresentwork,developmentofanefficienthydrogenperoxidesensorwasenvisa…     

Optimization and validation of a fast ultrahigh‐pressure liquid chromatographic method for simultaneous determination of selected sulphonamides in water samples using a fully porous sub‐2 μm column at elevated temperature

High temperature in HPLC is considered a valuable tool helping to overcome the increase in the column backpressure when using small packing particles such as sub‐2 μm, as it allows reduction in the mobile‐phase viscosity. In this study, a fast analytical method based on HPLC‐UV was developed using a sub‐2 μm column at elevated temperature for the simultaneous determination of nine sulphonamides. Owing to the lower viscosity of the mobile phase, the separation could be achieved in 3 min at 60°C for all analytes. The effect of temperature, the organic modifier percentage and the flow rate on the retention time was studied. The method developed was used for the determination of selected sulphonamides in surface and wastewater samples. Sample preparation was carried out by solid‐phase extraction on Oasis HLB cartridges. The method developed was validated based on the linearity, precision, accuracy, detection and quantification limits. The recovery ranged from 70.6 to 96 % with standard deviations not higher than 4.7%, except for sulphanilamide. Limits of detection ranged from 1 to 10 μg/L after optimization of all analytical steps. This method has the highest performance in terms of analytical speed compared with other published HPLC‐UV methods for the determination of sulphonamides in water.     

Synthesis and microstructural TEM investigation of CaCu3Ru4O12 ceramic and thin film

CaCu₃Ru₄O₁₂ (CCRO) is a conductive oxide having the same structure as CaCu₃Ti₄O₁₂ (CCTO) and close lattice parameters. The later compound is strongly considered for high density parallel plates capacitors application due to its so-called colossal dielectric constant. The need for an electrode inducing CCTO epitaxial growth with a clean and sharp interface is therefore necessary, and CCRO is a good potential candidate. In this paper, the synthesis of monophasic CCRO ceramic is reported, as well as pulsed laser deposition of CCRO thin film onto (001) NdCaAlO₄ substrate. Structural and physical properties of bulk CCRO were studied by transmission electron microscopy and electron spin resonance. CCRO films and ceramic exhibited a metallic behavior down to low temperature. CCRO films were (001) oriented and promoted a CCTO film growth with the same orientation.