Characterization of diamond-like carbon films by SEM, XRD and Raman spectroscopy

Diamond-like carbon films were deposited by electrolysis of a water-ethanol solution on Cu at low voltages (60-100 V) at 2 mm interelectrode separation. The films were characterized by scanning electron microscopy (SEM), X-ray diffractometer (XRD) and Raman spectroscopy. The films were found to be continuous and compact with uniform grain distribution. Raman spectroscopy analysis revealed two broad bands at ∼1350 and ∼1580 cm⁻¹. The downshift of the G band of graphite is indicative of the presence of DLC. For XRD analysis, the three strong peaks located at 2θ values of 43.2°, 74.06° and 89.9° can be identified with reflections form (1 1 1), (2 2 0) and (3 1 1) plane of diamond.     

XRD与SEM的钢渣尾渣物理激发机理研究

钢渣是冶金工业中产生的主要固体废弃物,其产量约为每年粗钢产量的15%~20%。由于技术的局限,导致我国钢渣利用率较低,仅为年钢渣产量的10%;同时加之管理制度的不健全,导致钢渣大量露天堆放,对土地资源、地下水源,以及空气质量造成严重影响。固体废弃物再利用是资源可持续发展的重要途径之一,由于钢渣的主要化学成分(CaO,SiO₂,A1₂O₃,MgO,Fe₂O₃,MnO,f-CaO等)、主要矿物组成(硅酸三钙、硅酸二钙、钙镁橄榄石、钙镁蔷薇辉石、铁酸二钙等)与水泥熟料的主要化学成分、主要矿物组成极为相似,是一种具有潜在胶凝活性的胶凝材料。以钢渣尾渣作为研究对象,采用机械研磨的方式对钢渣尾渣处理,即物理激发,获得不同粒径钢渣尾渣微粉。依据《用于水泥和混凝土中的钢渣粉》(GB/T 20491-2006)与《水泥胶砂强度检验方法(ISO法)》(GB/T 17671-1999)制备一系列钢渣尾渣胶砂试块(分别标记为A₄₀,A₆₀,A₈₀,A₁₀₀和A₁₂₀)。研究对钢渣尾渣胶凝活性的影响,以及不同水化时间对钢渣尾渣胶凝活性的影响,即3 d钢渣尾渣胶砂强度、7 d钢渣尾渣胶砂强度与28 d钢渣尾渣胶砂强度。利用激光粒度分析仪(LPSA)对钢渣尾渣微粉的粒径分布进行测试与分析,X射线衍射仪(XRD)对钢渣尾渣微粉与钢渣尾渣胶砂的矿物组成进行测试与分析,扫描电子显微镜(SEM)进行微观形貌测试与分析,从而获得钢渣尾渣的物理激发机理。结果表明,随着钢渣尾渣微粉粒径的减小,其胶凝活性呈现先增加后降低的趋势,当研磨时间为80 min时,A₈₀钢渣尾渣微粉的胶凝活性最高,即3 d活性指数为67.55%、7 d活性指数为71.96%和28 d活性指数为73.61%。随着钢渣尾渣微粉粒径的减小,钢渣尾渣微粉中RO相的XRD特征峰强度稳定,Ca₂SiO₄与Ca₃SiO₅的XRD特征峰强度呈现先增加后降低的趋势,Ca₃SiO₅与Ca₂SiO₄参与水化反应,生成一定量的Ca(OH)₂与C-S-H凝胶,具有良好的胶凝活性。A₈₀钢渣尾渣微粉中Ca₂SiO₄含量较少,而Ca₃SiO₅含量较多,均可以生成一定量的Ca(OH)₂与C-S-H凝胶,小幅提高A₈₀钢渣尾渣胶砂的早期(3~7 d)力学性能,大幅提高A₈₀钢渣尾渣胶砂的中、后期(7 d~28 d)力学性能。当水化时间3 d时,A₈₀钢渣尾渣胶砂中存在少量水化产物且大量分散小颗粒;当水化时间7 d时,A₈₀钢渣尾渣胶砂中水化产物大幅增加且形成较大颗粒;当水化时间28 d时,A₈₀钢渣尾渣胶砂中形成大量水化产物且几乎不存在分散小颗粒。从而进一步实现固体废弃物的资源化再利用,达到钢铁企业增加效益,环境缓解压力的目的。     

不同粒级辉钼矿的XRD和SEM及其可浮性差异研究

在浮选过程中,微细粒级的辉钼矿回收难度较大,易损失在尾矿中。为了分析不同粒级辉钼矿可浮性差异,揭示细粒级辉钼矿可浮性恶化的原因,以-150+74,-74+45,-45+38和-38 μm四个粒级辉钼矿为研究对象,通过辉钼矿纯矿物浮选试验,首次利用X射线衍射分析(XRD)、扫描电镜(SEM)及能谱(EDS)分析,对四个粒级辉钼矿的可浮性及其晶型特征和外在形貌的变化规律进行系统研究和对比。研究表明：随着粒级的减小,辉钼矿的可浮性降低,浮选效果恶化,且辉钼矿的可浮性由非极性、低能、疏水的“面”和活泼、亲水的“棱”的面积比决定。辉钼矿在受外力作用下由粗粒级变成细粒级过程中,首先主要是沿解理面破裂,然后沿断裂面的破裂增多,导致面棱比减小,辉钼矿的可浮性下降;同时辉钼矿晶型结构由3R亚稳定状态转变为2H型稳定状态。此外,与3R型的粗粒级辉钼矿相比,微细粒级辉钼矿以2H型为主,且其（002）晶面的面间距逐渐增大,导致水分子容易进入晶体结构内部,并在矿物表面形成水化膜,辉钼矿亲水性增强。晶型的不同使不同粒级辉钼矿的物理性质发生变化,面间距的增大则使辉钼矿断裂面暴露的亲水性钼-硫键数目增多,两者是细粒级辉钼矿亲水性增强及可浮性下降的本质原因。     

XPS, XRD and SEM characterization of a thin ceria layer deposited onto graphite electrode for application in lithium-ion batteries

Thin ceria layer deposited by electro-precipitation onto graphite was synthesised and characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The electro-precipitated ceria has a cubic structure with nanocrystallites of about 6 nm. The SEM analyses shows that the ceria layer reflects the morphology of the graphite electrode, exhibits small cracks usually found on the electro-precipitated films but covers almost completely the surface of the graphite. The ceria layer is composed of 75% Ce(IV) and 25% Ce(III) oxides as indicated by the XPS analyses. Cyclic voltammetry and galvanostatic charge-discharge tests in ethylene carbonate/dimethyl carbonate (1/1) (wt/wt) in the presence of 1 M LiPF₆ show that reversible lithium insertion and deinsertion occurs in the graphite/ceria electrode and that the ceria layer on the graphite electrode prevents from the loss of capacity during the first four cycles. The reduction of the electrolyte occurs at about 0.7 V vs Li/Li⁺ on both electrodes but XPS and SEM analyses show that the SEI layer is thin and not as homogenous on the graphite as on the graphite/ceria electrode. The composition of the SEI layer on the graphite/ceria electrode, mainly composed of Li₂CO₃, ROCO₂Li, R-CH₂OLi and LiF, is different than those obtained on the graphite.     

酒石酸钠调控草酸钙晶体生长的SEM,XRD和FTIR研究

采用扫描电镜(SEM)、X射线衍射(XRD)和傅里叶红外光谱(FTIR)研究了凝胶体系中尿抑制剂酒石酸钠(Na₂tart)的浓度和结晶温度对草酸钙(CaOxa)晶体生长的影响。当Na₂tart浓度为0.01 mol·L-1时,体系中主要生成棱角尖锐的蔷薇花状一水草酸钙(COM)聚集体,二水草酸钙(COD)含量小于5％,此时XRD图谱上主要为归属于COM的(101),(020)和(202)晶面的衍射峰,FTIR光谱中COM晶体的羧基不对称伸缩振动ν_as(COO-)和对称伸缩振动ν_s(COO-)分别为1 618和1 317 cm-1。当Na₂tart浓度增加到0.10和0.50 mol·L-1时,COD百分含量分别增加至10％和50％,COM晶体的比表面积减小。COD含量增加后,XRD图谱上归属于COD的(200),(211),(411)和(213)晶面的衍射峰增强。环境温度的影响比浓度的影响更为显著。高温(＞47 ℃)有利于COM生成,而低温(＜27 ℃)有利于Na₂tart诱导COD。FTIR光谱中COD的ν_as(COO-)和ν_s(COO-)分别为1 647.6和1 327.7 cm-1。     

利用SEM，XRD和FTIR研究四种化学预处理对楸木木屑酶解的影响

利用 NaOH ,Ca（OH）2,H2 SO4和 HCl 四种溶液对楸木木屑进行化学预处理,发现两种碱预处理均能显著提高楸木木屑的酶解效率。采用扫描电镜（SEM ）,X 射线衍射（XRD）和傅里叶红外光谱（FTIR）对四种化学预处理后的楸木木屑进行观察和分析。SEM 观察发现,四种化学预处理对楸木木屑的纤维表面均有不同程度的破坏与侵蚀,其中 Ca（OH）2的破坏效果最为明显。XRD 谱图表明,碱预处理对楸木木屑纤维素的非晶体结构产生破坏,导致其结晶度升高,而经过酸预处理后楸木木屑纤维素的结晶度没有明显变化。FTIR 谱图显示,酸碱预处理对楸木木屑中半纤维素和木质素的分子结构均有不同程度的破坏,碱预处理过程中木质素的高效溶出可能是楸木木屑酶解效率显著提高的主要原因。     

基于XRD和SEM的含碳微细粒金矿氧化焙烧机理研究

含碳微细粒金矿是世界难处理金矿主要类型,且储量巨大,矿石中的有机碳、石墨碳能吸附溶液中的金氰络合物,因而含碳金矿在浸出之前需进行预处理。氧化焙烧是应用时间最长、可靠性和适应性最好的预处理工艺,已经成功的用于生产实践。针对传统氧化焙烧法存在生产成本高,收尘系统复杂等不足,近年来国内外学者在焙烧工艺和设备方面进行了大量的研究工作,取得了丰硕的研究成果,为氧化焙烧技术的发展注入了新的活力。但关于焙烧理论方面的研究较少,研究方法也比较单一,尤其是对于焙烧过程的相关理论研究比较薄弱,这在一定程度上影响了氧化焙烧技术的发展。焙烧时间是影响焙烧效果的关键因素,决定化学反应进度及物相变化程度。在不同时间条件下(焙烧温度650 ℃),对含碳微细粒金矿石进行焙烧-浸出试验,首次采用X射线衍射(XRD)、扫描电镜(SEM)、能谱分析(EDS)和孔结构分析等手段对含碳金矿及焙砂进行分析表征,进而揭示氧化焙烧过程中碳质物的氧化、矿石晶体结构变化、物相变化等对金浸出效果的影响机理。工艺矿物学研究表明： 矿石中主要矿物有石英、白云石、方解石、绢云母、高岭石、黄铁矿和石墨等;矿石中自然金粒度微细,以5～10 μm粒级为主,部分微粒自然金被石英、碳质组成的碎屑包裹;碳质(有机碳和石墨碳)含量高、粒度细,且与脉石矿物紧密共生。焙烧-浸出试验结果表明： 原矿直接浸出时,金浸出率仅为12.50%,碳质的“劫金”作用显著;随着焙烧时间的增加,金的浸出率先逐渐增大后变化平稳,焙烧时间为2 h时,金浸出率最高;当焙烧时间为1 h 时,绢云母发生了脱羟基变化,高岭石分解生成蒙脱石,黄铁矿氧化为赤铁矿,碳质(有机碳和石墨碳)氧化且产生CO₂,但未完全氧化,此时焙砂中石英的d₁₀₀和d₁₀₁值以及平均孔径较小,不利于浸出剂的扩散,导致金浸出率仅为58.09%;当焙烧时间为1.5 h 时,白云石开始分解,碳质已完全燃烧,产生的CO₂使微孔数量增多,有利于浸出剂的扩散,此时金浸出率增加到73.34%;当焙烧时间为2 h时,白云石分解较完全,焙砂中有MgO生成,此时焙砂中石英的d₁₀₁值达到最大值(4.255 03 nm),焙砂松散密度变大且孔容和平均孔径达到最大值,分别为0.009 954 cm3·g-1和6.640 80 nm,焙砂中产生的微孔最多,增加了浸出剂的扩散通道,有利于金的浸出,金浸出率也达到了最大值(91.28%);当焙烧时间为3 h时,焙砂表面生成Ca₂SiO₄和CaSO₄等在高温时易形成低熔点物质,发生微弱的烧结现象,导致颗粒内部的微孔被填充、闭合,微孔减少,孔容和平均孔径降低,内部结构变得致密,不利于浸出剂的扩散,同时造成金的浸出率下降。     

FTIR, XRD, SEM and solid state NMR investigations of carbonate-containing hydroxyapatite nano-particles synthesized by hydroxide-gel technique

Nano-crystalline hydroxyapatite (HA), Ca₁₀(PO₄)₆(OH)₂ has been synthesized by a precipitate conversion technique using hydroxide gel at lower temperatures, e.g. 80 °C. HA crystallizes in hexagonal structure (space group: P6₃/m) having lattice parameters: and and around 17 nm in crystallite-size for the 80 °C-heated sample. SEM micrographs show hexagonal crystallites of average particle dimensions approximately 50×20 nm for 80 °C heated sample. The structure analysis by XRD, FTIR, ¹H and ³¹P MAS NMR show the existence of structural disorder at the particle surface that either does not form hydrogen bonding due to lack of adequate bonding parameters or forms a very weak dipolar bonding. The structural disorder has been explained as a result of chemical interactions between the phosphate groups either with the surface adsorbed water or the hydroxyl groups at the surface of the nano-particles.     

基于XRD与SEM研究风淬渣微粉用于重金属污染土壤的修复机理

钢渣是冶金工业中产生的主要固体废弃物,其产量约为每年粗钢产量的15%~20%。由于技术的局限,导致我国钢渣利用率较低,仅为年钢渣产量的10%,同时加之管理制度的不健全,导致钢渣大量露天堆放,对土地资源、地下水源,以及空气质量形成严重影响。面对上述问题,利用钢渣开发一种价格低廉的固化药剂用于重金属污染土壤的修复,既是冶金固体废弃物可持续发展的重要途径之一,也是大幅降低重金属污染土壤修复成本的重要途径之一。该研究创新性是用风淬渣微粉作为固化药剂对含有Cd,Cu,Pb,Ni和Zn的重金属污染土壤进行修复。研究了风淬渣粉磨时间、风淬渣微粉掺量和养护时间对修复重金属污染土壤效果的影响。利用激光粒度分析仪测试风淬渣微粉的粒度分布、比表面积与孔隙度吸附仪测试风淬渣微粉的孔结构、扫描电子显微镜测试风淬渣微粉-重金属污染土壤混合物的微观形貌、X-射线衍射仪测试风淬渣微粉的矿物成分,分析风淬渣微粉修复重金属污染土壤的机理。结果表明,风淬渣的性质安全,对生态环境不存在污染,可以用于修复重金属污染土壤的固化技术。当风淬渣粉磨时间为100 min、风淬渣微粉掺量为20%、养护时间为14 d时,风淬渣微粉对重金属污染土壤中Cu,Cd,Ni,Zn和Pb的固化效果均达到91%以上。随着风淬渣粉磨时间的延长,风淬渣微粉的粒径尺寸减小、粒度分布趋向均匀。风淬渣的多孔结构破坏、比表面积提高,有利于提高风淬渣微粉对重金属污染土壤的修复效果。随着风淬渣微粉掺量的增加,风淬渣微粉形成的水化凝胶（C-S-H）数量增加,有利于提高风淬渣微粉包裹重金属污染土壤的效果,以达到固化重金属污染土壤中Cd,Cu,Pb,Ni和Zn的目的。风淬渣微粉对固化重金属污染土壤中Cu,Cd,Ni,Zn和Pb具有选择性,在不同养护时间下,重金属分别以Cd₂SiO₄,Cu(OH)₂·2H₂O,PbCO₃,3Ni(OH)₂·2H₂O,Ni₂SiO₄,Zn(OH)₂和Zn₂SiO₄形式存在。     

Melting and solidification in laser-irradiated HgCdTe

The results of the numerical analysis of the effects induced by pulsed Nd:YAG and ruby laser on Hg_0.8Cd_0.2Te are presented. The proposed model facilitates the planning of HgCdTe laser processing and the choice of the processing parameters such as: melt depth, melt duration of the surface layer and melt front velocity, as well as the irradiation parameters. The influence of the optical parameters and the temperature dependence of the HgCdTe thermal parameters on the results of laser irradiation are specially analyzed.     

AgI nanostructure development in sputter-disordered and Al-doped Ag films probed by XRD,SEM, optical absorption and photoluminescence

By use of thermal evaporation and rf magnetron sputtering 300 and 500 Å thick Ag and Ag (Al) films were prepared. γ-AgInanoparticles were formed during (a) short time (2–5 min) iodization of undoped thermally evaporated Ag films, (b) longer time (12 h) iodization of undoped rf sputtered Ag films and (c) short time (2–15 min) iodization of thermally evaporated Ag_0.95Al_0.05 and Ag_0.90Al_0.10 films of 500 and 300 Å thickness respectively. Both rf sputtered and Al doped Ag films yielded ～20 to ～60 nm sized γ-AgI particles upon iodization. Optical absorption spectra reveal Z_1,2 and Z₃ exciton transitions with increased broadening of γ-AgI nanoparticles, suggesting the effect of disorder produced during film formation. Blue shift observed with increasing film thickness could be the effect of decreasing particle size, thereby increasing the quantum confinement effects. Photoluminescence studies show that the donor-acceptor recombination rate, enhanced by 25% for Ag_0.95Al_0.05I film relative to that of undoped AgI, is due to the tight binding of Al to surface defect sites.     

Heating and compression of laser-irradiated spherical targets

Heating and dynamics of compression of shell targets irradiated by a nanosecond laser pulse in the “Kal'mar” facility are investigated. Comprehensive procedures are developed and used to investigate the energy balance and the compression dynamics of the target scattered by the radiation plasma at the harmonic frequencies 2ω₀ and 3/2ω₀, and of the spectral distribution of the continuous x radiation. The use of the developed procedures has made it possible to clarify the dependence of the components of the energy balance on the target parameters, to establish new regularities governing the shell motion, to identify the phenomena that take place in the region of the critical and quarter-critical density, and to demonstrate experimentally the possibility of reaching in the “exploding pusher” regime densities much higher than the density of a solid body.     

Local structure of hydroxy-peroxy apatite: A combined XRD, FT-IR, Raman, SEM, and solid-state NMR study

The synthesized hydroxyapatite (HAp) and hydroxy-peroxy apatite are studied using various techniques, such as X-ray powder diffraction, FT-IR and Raman spectroscopy, scanning electron microscopy, and solid-state NMR spectroscopy. The experimental data suggest that hydroxy-peroxy apatite contains a small amount of hydration of partially dehydroxylated hydroxyapatite phase and calcium hydroxide. The incorporation of peroxide ions into the lattice of HAp causes perturbations of the hydrogen environments and slight changes in its crystal morphology. The distance between H in some structural OH⁻ and adjacent O along the c-axis becomes longer instead of forming a hydrogen bond after the incorporation of peroxide ions.     

Characterization of minerals in air dust particles in the state of Tamilnadu,India through FTIR,XRD and SEM analyses

The abstract of this paper explains the presence of minerals in air which causes great concern regarding public health issues. The spectroscopic investigation of air dust particles of several samples in various locations in the state of Tamilnadu, India is reported. Qualitative analyses were carried out to determine the major and minor constituent minerals present in the samples based on the FTIR, XRD absorption peaks. This study also identified the minerals like quartz, asbestos, kaolinite, calcite, hematite, montmorillonite, nacrite and several other trace minerals in the air dust particles. The presents of quartz is mainly found in all the samples invariably. Hence the percentage of quartz and its crystalline nature were determined with the help of extinction co-efficient and crystallinity index respectively. The shape and size of the particulates are studied with SEM analysis.     

XRD and XPS analysis of laser treated vanadium oxide thin films

In this work, we present X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) analysis of laser treated vanadium oxide sols. The films were also observed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM) to reveal how the original xerogel structure changes into irregular shaped, layer structured V₂O₅ due to the laser radiation. XRD revealed that above 102 W/cm² the original xerogel structure disappears and above 129 W/cm² the films become totally polycrystalline with an orthorhombic structure. XPS spectra showed O/V ratio increment by using higher laser intensities.     

Measurement of shock heating in laser-irradiated solids

We have obtained the first temporally resolved measurement of the entire visible spectrum of shock-induced luminescence from the rear surface of a laser-irradiated aluminum foil. This yielded a detailed time history (200 ps resolution) of the spectral temperature of the target rear surface. The results were consistent with that obtained from brightness temperature measurements. The measured shock-heated temperature also showed good agreement with hydrodynamic simulations addressing the effect of shock-unloading in the target rear side.     

Investigation on non-LTE radiation emitted from a laser-irradiated Au disk

1 Introduction The laser-target coupling physics is a key topic in indirect-driven inertial confinement fusion (ICF) and X-ray application research[1―3]. When intense laser light irradiates the solid target, the plasmas are produced rapidly on the surface of the target. The laser en-ergy is mainly absorbed by inverse bremsstrahlung absorption, and a coronal region with high-temperature and low-density plasma is formed. Electron thermal conduction proc-ess transfers energy into over-dense re…     

Surface topography of ultrashort laser-irradiated CaF2

A single-crystal CaF₂ (111) was irradiated with single and multiple laser (Ti:sapphire, 800 nm, 25 fs) shots at fluences ranging from 0.25 to 1.5 J cm^?2. In this fluence regime, a single laser pulse usually leads to typical bump-like features ranging from 200 nm to 1.5 μm in diameter and 10–50 nm in height. These bumps are related to compressive stresses due to a pressure build-up induced by fast laser heating and their subsequent relaxation. When CaF₂ is irradiated with successive (in our case 20) shots at a laser fluence of 1.5 J cm^?2, nanocavities at the top of the microbumps are observed. The formation of these nanocavities is regarded as an explosion and is attributed to the explosive expansion generated by shock waves due to laser-induced plasma after the nonlinear absorption of the laser energy by the material. Such kinds of surface structures at the nanometre scale could be attractive for nanolithography.     

Lal-xTexMnO3晶格结构的X射线粉末衍射分析

通过X射线粉末衍射数据,用Rietveld精修方法分析了Te部分替换LaMnO3中La后,其晶格参数及其结构对称性所发生的变化.结果表明:Te掺杂LaMnO3系列样品具有R(3)C的晶格结构对称性,其MnO6八面体晶格还产生了伸张畸变,畸变程度随Te掺杂量的增加而增大.此外根据Mn-O-Mn键角、eg电子能带的带宽、A位离子平均半径及A位离子尺寸失配度等的变化特点,推测Te掺杂LaMnO3样品除居里温度等相变物理量将随x增加而非线性变化外,还可能产生自旋玻璃态、相分离等宏观现象.