ICP-AES测定微硅粉中Ca、Mg、Fe和Al的含量

微硅粉样品经氢氟酸、硝酸、高氯酸消解,电感耦合等离子体-原子发射光谱法（ICP-AES）测定Ca、Mg、Fe、Al杂质元素含量。方法的回收率为：Ca 95.2%—100.3%,Mg 96.2%—99.6%,Fe 95.8%—97.2%,Al 98.6%—104.6%,精密度在1.50%—2.59%之间。本方法线性范围宽、分析效率高、具有良好的准确性和精密度,能快速准确地测定微硅粉中Ca、Mg、Fe和Al杂质元素的含量。     

ICP-AES测定钛铝系金属间化合物中钽、硅

采用ICP-AES法测定钛铝系金属间化合物中Ta、Si的含量,研究了基体元素和共存元素的干扰以及消除方法。在本方法的测定范围内(Si0.05%—1.00%、Ta0.10%—4.00%),钽、硅测量的相对标准偏差(n=8)小于6%。方法简便、快捷,结果准确。     

掺硅类金刚石膜的制备与力学性能研究

用脉冲电弧离子镀技术,通过调整掺硅石墨靶和纯石墨靶的数量,制备了一系列不同硅含量的类金刚石薄膜样品.研究发现：当硅含量达6.7at.%时,类金刚石薄膜的应力从4.5GPa降低到3.1GPa,薄膜的硬度还保持在3600Hv,和没有掺杂的类金刚石薄膜的硬度相比,基本保持不变;当硅含量小于6.7at.％时薄膜的摩擦系数相对于未掺杂的类金刚石薄膜也保持不变,为0.15.当薄膜中硅含量继续增加时,薄膜中C—Si键的含量增多,导致薄膜硬度和应力都有较大幅度地减小、摩擦系数增大、磨损性能也变差了. 关键词： 类金刚石膜 掺硅 应力 硬度     

基准物质燃烧红外吸收法测定硅中总碳量

以碳酸钠为基准物质 ,配成一系列标准溶液 ,在通有纯氧气的高频炉中燃烧 ,红外吸收法测定碳含量 ,绘制校准曲线 ,测定硅中总碳量 ,与推荐值基本一致 ,方法准确、结果满意。方法适用范围为 0 .0 10 %—0 .2 0 % ,RSD在 0 .5 %— 2 .0 %之间     

硅镁凝胶对杉木的强化及固着机制研究

硅镁凝胶浸渍改性杉木在物理力学性能方面提升较佳,探究硅镁凝胶在杉木中的固着性能和机制,对后续研究与创新具有一定意义。以硅镁凝胶为改性药剂,人工林杉木为基材,浸渍干燥后制得改性杉木。通过FTIR和XPS分析杉木素材和改性杉木的化学成分和结合方式,并对硅镁凝胶在木材中的分布以及改性杉木的渗透性进行探讨。实验结果表明：硅镁凝胶浸渍改性杉木的物理力学性能得到明显改善,密度均达到0.5 g·cm-3以上,抗压强度和抗弯强度相比杉木素材分别提升了99.73%和58.48%,端面硬度从3 659 N提升到5 843 N,基本已达到中等木材的性能指标。EDS结果证明药剂在杉木细胞腔中填充状况良好,Si,O,Na和Mg等主要元素与浸渍药剂硅镁凝胶相符且分布均匀。对浸洗前后的改性杉木试样和素材分别进行分层XPS测试,改性材的O/C增大,各元素在不同深度的含量十分接近,硅镁凝胶在杉木中分布均匀,具有良好的渗透性;浸洗后Si元素含量稳定,而钠元素有所降低,可能是部分钠盐的溶解流失造成,且不同深度的元素含量变化趋于一致,改性杉木的抗流失性较好。相比于硅酸钠浸渍改性杉木,硅镁凝胶改性杉木在96 h流失率降低到10.8%,抗流失效果较好。FTIR测试结果表明硅酸钠溶液对杉木的木质素和半纤维素有破坏和脱出作用,对杉木的通透性有所改善,且更容易与药剂形成化学键结合。C,O和Si元素的XPS谱图结果表明,改性后C(1s)向低结合能偏移,性质更加稳定,O—H结合大量减少,Si—O结合增多,硅镁凝胶能够在杉木中形成稳定的Si—O—C化学结构,药剂能够在细胞壁上实现高效固着。研究结果为改性材的药剂流失性检测和固着性研究提供新的思路,为硅镁凝胶浸渍改性杉木后续研究提供一定的理论支持。     

氧弹燃烧灰化分光光度法测定有机物中的硅

采用氧弹燃烧灰化进行样品预处理 ,亚铁还原硅钼蓝分光光度法测定有机物中微量硅。通过试样分析和回收率实验 ,结果表明 ,方法的回收率为 95 %— 10 2 % ,可用于有机样品中硅的定量测定。     

微波消解-电感耦合等离子-质谱法测定船用燃料油中钒、铝、钙、锌、镍、钠、铁和硅

船用燃料油样品经微波消解后,采用电感耦合等离子-质谱法(ICP-MS)测定其中的钒、铝、钙、锌、镍、钠、铁和硅含量。方法在0—100μg/L范围内线性良好,仪器检出限为0.005—12.89μg/L,其回收率在90.39%—107.48%之间,相对标准偏差小于2.0%。本方法具有检出限低、准确度高、精密度好和多种元素同时测定等优点,完全满足船用燃料油实际样品的测试需要。     

光化学还原-硅钼蓝分光光度法测定硅的研究

用紫外可见分光光度计,气相色谱仪,光化学反应箱和反应皿,以及阳光、铟灯、荧光高压汞灯、紫外灯等光源,研究了β硅钼黄-乙醇溶液体系的光化学还原反应,并建立了光化学还原-硅钼蓝分光光度测硅法。研究表明,发生该反应的光的有效波长460nm;乙酸、丙酮、苯酚等不能,而其他水溶性的醇、醛、羧酸、醚、酯存在能导致该反应的发生;在0.8—2mol/L盐酸或0.4—1mol/L硫酸或1—3mol/L高氯酸、0.32%—0.48%的钼酸铵、4%—10%的乙醇中,≤8mg/L SiO_2的/β硅钼黄溶液光照10min就能定量还原成硅钼蓝;还原产物稳定,最大吸收波长为810nm,ε_(800)=2.7×10~4L·mol~(-1)·cm~(-1);分析微量二氧化硅S≤0.012%、RSD≤1.3%。初步探讨,乙醇与硅钼黄形成了电子给予体-接受体配合物(DAC),光照反应后有乙酸产生。     

ICP-AES测定三元复合驱采出液中硅含量分析研究与应用

应用ICP-AES测定三元复合驱采出液中硅含量,选用Thermo Elemental ICAP 6300型电感耦合等离子体-原子发射光谱仪,选择251.6nm谱线,测得方法检出限为0.0111mg.L-1,加标回收率为91.0%—100.6%,相对标准偏差为0.58%,方法精密度、准确度较高,检测线性范围宽。该方法操作简便,测定速度较快,共存干扰元素少。当采出液中表面活性剂浓度在500mg/L以下时,对检测结果基本没有影响;矿化度较高的油田水及聚合物浓度大小对测定有影响,但经过处理后都能满足检测要求。可应用于三元复合驱采出液中硅含量的测定。     

ICP-AES测定电解镍中的杂质元素

采用电感耦合等离子体发射原子发射光谱法(ICP-AES)测定了电解镍中锰、磷、钴、铁、铜、镁、铝、锌、镉、硅和锡等11种元素的含量,对仪器各项参数进行优化,采用基体匹配办法克服基体干扰,通过选择合适的分析谱线和背景校正消除共存元素间干扰。方法应用于实际样品分析,11种元素的回收率为92.0%—107.0%,相对标准偏差0.3%—5.1%,测定结果与标准方法的测定值相符。     

ESCA studies of Si-Fe alloys

ESCA examination of films formed on Si-Fe alloys after immersion in 0.1 M NaCl for 24 h has hown that the thickness of passive films decreased with an increase in silicon content. A thick passive film containing oxidized silicon and oxidized iron was formed on Fe-20 wt% Si and the oxidized iron was about three times higher than the oxidized silicon in the passive film. However, an obvious reduction in the oxidized iron in the film on Fe-30 wt % Si was observed. Oxidized iron was detected up to a depth of 1.0 nm and at a depth greater than 1.0 nm from the surface, the film was exclusively in oxidized silicon. The film was exclusively silicon oxide when the silicon content was increased to 50 wt %. Electrochemical techniques according to ASTM G59 and ASTM G5 were used for the determination of the relative corrosion rate. Fe-50 wt % Si was found to have a corrosion rate smaller than those lower silicon alloys. This relates to the surface film composition and structure as determined by ESCA.     

Removal of oxygen from silicon by electron beam melting

Small amounts of multicrystalline silicon were melted in an electron beam furnace in different experimental conditions in order to investigate the oxygen evaporation behavior during the electron beam melting (EBM) process. The oxygen content level before and after EBM was determined by secondary ion mass spectroscopy. The oxygen content was reduced from 6.177 to 1.629 ppmw when silicon was melted completely at 15 kW with removal efficiency up to 73.6 %. After that, it decreased continually to <0.0517 ppmw when the refining time exceeded 600 s with a removal efficiency of more than 99.08 %. During the melting process, the evaporation rate of silicon is 1.10 × 10^?5 kg/s. The loss of silicon could be reduced up to 1.7 % during oxygen removal process to a desirable figure, indicating EBM is an effective method to remove oxygen from silicon and decrease the loss of silicon.     

一种快速测定草类原料制浆黑液中硅含量的新方法

应用基于α-型硅钼黄显色的分光光度法进行草类原料蒸煮黑液中硅含量的测定。测定波长360nm,pH 4.0,时间10min。实验中采用过氧化氢-硝酸消解法消除样品中木素成分对光度检测的干扰。研究表明:该方法的相对偏差及回收率分别为0.9%和99.0%～102%。该方法具有操作简便、快速,稳定性好,准确性高,试剂干扰少的优点,可用于黑液中高硅含量的日常快速分析。     

Preparation of composition-controlled silicon oxynitride films by sputtering; deposition mechanism,and optical and surface properties

Silicon oxynitride films have been grown on silicon by current-controlled reactive sputtering. The content of oxygen in the films could be well controlled by regulating the sputtering current under the reactive gas of Ar+ N₂ with an oxygen content of around 3%. The atomic ratio of oxygen to nitrogen in the silicon oxynitride film became larger with increasing sputtering current. It has been found that electron irradiation of the silicon substrate induces adsorption of oxygen and nitrogen. The degree of oxygen adsorption was about ten times larger than that of nitrogen. This phenomenon is a key mechanism in controlling the film composition. The adsorptive mechanism might be explained by the phenomenon of surface activation by the electron bombardment. Utilizing this technique, wettability by germanium of silicon oxynitride films could be controlled by varying their oxygen and nitrogen contents. A better wetting condition was obtained from films with large atomic ratio of nitrogen to oxygen in the silicon oxynitride film.     

Er离子注入的富硅SiO2MOS-LED的可见和红外电致发光特性

通过Er离子和Si离子注入并结合高温退火制备了Er掺杂的富硅SiO2薄膜以及ITO/SiON/富硅SiO2:Er/Si MOS结构电致发光器件.研究了富Si浓度的变化对Er3+离子掺杂的电致发光器件的发光性能和传导特性的影响.发现不同Si含量对Er3+离子的不同能级的电致发光会产生不同作用.在富Si量小于5％的条件下,...     

Thermoelectrics from silicon nanoparticles: the influence of native oxide

Thermoelectric materials were synthesized by current-assisted sintering of doped silicon nanoparticles produced in a microwave-plasma reactor. Due to their affinity to oxygen, the nanoparticles start to oxidize when handled in air and even a thin surface layer of native silicon oxide leads to a significant increase in the oxide volume ratio. This results in a considerable incorporation of oxygen into the sintered pellets, thus affecting the thermoelectric performance. To investigate the necessity of inert handling of the raw materials, the thermoelectric transport properties of sintered nanocrystalline silicon samples were characterized with respect to their oxygen content. An innovative method allowing a quantitative silicon oxide analysis by means of electron microscopy was applied: the contrast between areas of high and low electrical conductivity was attributed to the silicon matrix and silicon oxide precipitates, respectively. Thermoelectric characterization revealed that both, electron mobility and thermal conductivity decrease with increasing silicon oxide content. A maximum figure of merit with zT = 0.45 at 950 °C was achieved for samples with a silicon oxide mass fraction of 9.5 and 21.4% while the sample with more than 25% of oxygen clearly indicates a negative impact of the oxygen on the electron mobility.     

Structure and strength of Al-Si alloys obtained by the Stepanov method

Al-Si alloy samples with a silicon content from 8 to 15 wt % were obtained by the Stepanov method at solidification rates of 10² and 10³ µm s^?1. Tensile and bending strain diagrams were studied at a strain rate of about 10^?4 s^?1. The microstructure of the samples was investigated. It was found that the silicon content in the eutectic structure of the alloy grows as the solidification rate increases. The yield stress and the tensile strength increase as the silicon content grows.     

ICP-AES测定锰矿中二氧化硅含量

试样经氢氧化钠和过氧化钠混合熔剂碱熔,再用酸浸提,干过滤后定容.采用ICP-AES测定锰矿中二氧化硅含量.本法测定锰矿标样(冶金部标准样品505)中二氧化硅含量,其测定结果的相对标准偏差RSD为1.08%,测定平均值为33.93%(标样推荐值为33.58%).     

磁控共溅射低温制备多晶硅薄膜及其特性研究

多晶硅在光电子器件领域具有较为重要的用途。利用磁控溅射镀膜系统,通过共溅射技术在玻璃衬底上制备了非晶硅铝(α-Si/Al)复合膜,将Al原子团包覆在α-Si基质中,膜中的Al含量可通过Al和Si的溅射功率比来调节。复合膜于N₂气氛中进行350 ℃,10 min快速退火处理,制备出了多晶硅薄膜。利用X射线衍射仪、拉曼光谱仪和紫外-可见光-近红外分光光度计对多晶硅薄膜的性能进行表征,研究了Al含量对多晶硅薄膜性能的影响。结果表明：共溅射法制备的α-Si/Al复合膜在低温光热退火下晶化为晶粒分布均匀的多晶硅薄膜;随着膜中Al含量逐渐增加,多晶硅薄膜的晶化率、晶粒尺寸逐渐增加,带隙则逐渐降低;Al/Si溅射功率比为0.1时可获得纳米晶硅薄膜,Al/Si溅射功率比为0.3时得到晶化率较高的多晶硅薄膜,通过Al含量的调节可实现多晶硅薄膜的晶化率、晶粒尺寸及带隙的可控。     

基于多分辨分析的高炉铁水含硅量波动多重分形辨识

以包钢6号高炉、邯钢7号高炉和莱钢1号高炉在线采集的铁水含硅量(［Si］)的时间序列为样本, 利用多分辨分析剔除样本的长期趋势,对样本保留的波动趋势进行多重分形特征辨识. 通过计算广义Hurst指数、尺度函数、多重分形谱, 全面、细致量化了序列的局部及不同层次的波动奇异性. 计算结果表明: 去除长期趋势后, 三座高炉［Si］序列的波动呈现显著多重分形特征, 这样的波动过程仅用单一的Hurst指数或box维数来描述是不够的. 关键词： 多分辨分析 铁水含硅量 波动 多重分形