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本文主要论述了离心球墨铸铁管生产中原铁水的五大元素的直读光电光谱分析,以及球化处理后铁水中五大元素及残留镁的直读光电光谱分析。由于采用快速急冷的薄片样,试样完全白口化,解决了灰铸铁及球墨铸铁试样白口化难的问题;采用60#刚玉砂轮预磨,46#刚玉砂纸研磨试样,实践证明,选择合适的光谱分析条件,灰铸铁及球墨铸铁中五大元素及镁的分析结果完全达到生产要求。 相似文献
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重整催化剂及其担体中微量铁的原子吸收光谱分析 总被引:1,自引:1,他引:0
汪昌仑 《光谱学与光谱分析》1988,(5)
实验方法与装置一、试样预处理为了尽量减少污染,试样不需研磨,经150℃烘一小时,于干燥器中冷却后,根据含量范围称取一定量的试样,置于密闭加压溶样器中,加入1:1的H_2SO_45—10ml,在烘箱内于110℃加热2小时溶解。冷却后以蒸馏水稀至一定体积待用。即使有少量悬浮物也不影响原子吸收的测定工作。 相似文献
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机械研磨影响高岭石结构的光谱研究 总被引:1,自引:1,他引:0
将高岭石矿物分别用干法和湿法连续研磨,通过不同研磨时间各粉样的傅立叶变换红外光谱(FTIR)及X射线衍射光谱(XRD)的实测和比较,发现干法研磨12h高岭石的结构开始改变,经42h其层状结构完全破坏。但在湿法条件下即使研磨54h,高岭石的结构也无明显变化。由此可见,湿汉研磨比干法好。文中还初步探讨了研磨影响粘土结构的原因。 相似文献
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本研究了研磨对Bi-Sr-Ca-Cu-O超导体2212相的影响,发现干法研磨导致晶相向非晶态的转变,而加入有机溶剂的湿法研磨对晶体结构破坏很小。对两种不同研磨条件下,Cu原子和Bi原子局域结构的EXAFS研究,发现Bi原子第一配位层配位状态基本无变化,第二、第三层原子配位距离相同,但无序度显增大,而Cu原子第一配位层中两种不同配位环境氧原子的无序度有不同程度的增大。由此推断,研磨所导致的非晶态 相似文献
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气缸工作表面必须生成储油结构。在缸套工作表面原已形成数以万计、相互独立、深度一致的微坑,在此基础上,本文使用超声微研磨方法再形成一些细小的、不均匀分布的微细沟槽或点坑,以形成复合储油结构。文章提出了超声微研磨方法,设计了超声微研磨装置,测量了超声换能器的谐振频率,为工业化试验和应用奠定了基础。 相似文献
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胆红素—氟化钡体系固相研磨反应的红外光谱研究 总被引:3,自引:0,他引:3
本文利用红外光谱法对胆红素-氟化钡体系的固相研磨反应进行了研究。结果表明,该固相研磨反应具有氧参加的自由基反应机制,并且反应产物中胆红素与钡离子的络合形式五液相反应合成的胆红素钡络合物不同。 相似文献
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本文对KBr压片法、KCl压片法以及萨特勒图谱采用的,糊剂法所绘制的三氯异氰尿酸的红外光谱进行了分析、对照。KCl压片法克服了溶剂的影响,简单、直观地体现了物质的精细结构。同时,将三氯异氰尿酸分别与KCl、KBr研磨,和三氯异氰尿酸纯品进行了紫外-可见吸收光谱对照。实验发现,与KBr研磨的三氯异氰尿酸和纯品的吸收峰有差异,而与KCl研磨后的三氯异氰尿酸和纯品一致,说明结构未发生变化。因此,认为KCl压片法是绘制三氯异氰尿酸红外光谱较好的方法。 相似文献
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研磨丝杠是一项技术性很强的工作,除了要正确选择丝杠与研磨的材料、磨具设计、热处理规范,以及确定研磨手法等外,还需要一种简便而可靠的测量装置,以便对研磨中的丝杠随时进行检测,保证整个研磨工作顺利进行。本文介绍的是我们在研磨精密丝杠时采用的方法——多光束干涉法,整个测量装置结构简单,测量精度高,使用起来也很方便。 相似文献
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This paper addresses the chemical characterisation of silicon carbide‐based grinding tools. These are among the most widely used grinding tools in the ceramic sector, and instruments are required that enable the grinding tool quality to be controlled, despite the considerable complexity involved in determining grinding tool chemical composition. They contain components of quite different nature, ranging from the silicon carbide abrasive to the resin binder. To develop the analysis method, grinding tools containing silicon carbide with different grain sizes were selected from different tile polishing stages. To develop the grinding tool characterisation method, the different measurement process steps were studied, from sample preparation, in which different milling methods (each appropriate for the relevant type of test) were used, to the optimisation of the determination of grinding tool components by spectroscopic and elemental analyses. For each technique, different particle sizes were used according to their needs. For elemental analysis, a sample below 150 µm was used, while for the rest of the determinations a sample below 60 µm was used. After milling, the crystalline phases were characterised by X‐ray powder diffraction and quantified using the Rietvel method. The different forms of carbon (organic carbon from the resin, inorganic carbon from the carbonates and carbon from the silicon carbide) were analysed using a series of elemental analyses. The other elements (Si, Al, Fe, Ca, Mg, Na, K, Ti, Mn, P and Cl) were determined by wavelength‐dispersive X‐ray fluorescence spectrometry, preparing the sample in the form of pressed pellets and fused beads. The chemical characterisation method developed was validated with mixtures of reference materials, as there are no reference materials of grinding tools available. This method can be used for quality control of silicon carbide‐based grinding tools. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Huaming Yang Wuguo Yang Yuehua Hu Chunfang Du Aidong Tang 《Particle & Particle Systems Characterization》2005,22(3):207-211
Dry grinding of illite particles has been investigated by X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and nitrogen adsorption techniques. Prolonged grinding results in an amorphous illite structure and the mechanochemical effect markedly promotes a reduction in reflection intensities with increased grinding time. It is confirmed that illite is very susceptible to alteration by grinding. The illite crystal size (d006) appears to reach a limit after 2 h of grinding. N2 adsorption studies indicate that illite ground for 8 h shows a larger average pore diameter than a sample after 4 h grinding or the original illite. It is inferred that grinding is good for the formation of macrostructural pores. Illite grinding results in a decrease in the Brunauer‐Emmet‐Teller (BET) surface area and total pore volume. IR spectroscopy shows a slight alteration in the illite bands after mechanochemical processing and some new bands were detected after 4 or more hours of grinding. 相似文献
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A simple sample preparation technique for materials unstable in air has been developed for electron microscope studies. The
materials already exist in the form of particles, or they can be transformed by mechanical grinding. The technique consists
of several stages: preparation of perforated or thin carbon films as substrates, mechanical grinding and ultrasonic treatment
of the material under investigation in a liquid substance to form a suspension, and dripping the suspension onto a substrate
placed in a microscope holder beforehand, followed by immediately placing the holder in the preliminary pumping chamber of
the microscope. 相似文献
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Effects of grinding-induced grain boundary and interfaces on electrical transportation and structure phase transition in ZnSe under high pressure 下载免费PDF全文
Interface and scale effects are the two most important factors which strongly affect the structure and the properties of nano-/micro-crystals under pressure.We conduct an experiment under high pressure in situ alternating current impedance to elucidate the effects of interface on the structure and electrical transport behavior of two Zn Se samples with different sizes obtained by physical grinding.The results show that(i) two different-sized Zn Se samples undergo the same phase transitions from zinc blend to cinnabar-type phase and then to rock salt phase;(ii) the structural transition pressure of the859-nm Zn Se sample is higher than that of the sample of 478 nm,which indicates the strong scale effect.The pressure induced boundary resistance change is obtained by fitting the impedance spectrum,which shows that the boundary conduction dominates the electrical transport behavior of Zn Se in the whole experimental pressure range.By comparing the impedance spectra of two different-sized Zn Se samples at high pressure,we find that the resistance of the 478-nm Zn Se sample is lower than that of the 859-nm sample,which illustrates that the sample with smaller particle size has more defects which are due to physical grinding. 相似文献
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激光诱导击穿光谱(LIBS)对固体进行检测时,受固体的表面物理形态和化学特性影响较大,因此,基体效应分析对LIBS在线检测研究有重要的意义。为了提高LIBS对表面凹凸不平样品成分在线检测的准确度,进行了LIBS对不同颗粒度铁屑样品的定量分析。实验所用的9种铁屑样品性状为松散的粉末、颗粒或长条状,为防止激光与样品相互作用时发生飞溅,将样品粘到双面胶上进行固定。采用的激发波长为1 064 nm、脉冲能量为35 mJ,探测器延时和积分门宽分别设置为1和10μs。为评估样品颗粒度不同导致的基体效应对LIBS光谱的影响,首先,利用主成分分析(PCA)对系列样品进行分类,结果显示,粉末状的四个样品被分出,即颗粒度不同导致的基体效应是样品光谱信号差异的主要原因。其次,以C3、 C5两个样品研磨前后的基体元素特征谱线FeⅠ330.635 nm为研究对象,通过对比谱线的强度和相对标准偏差(RSD)发现,颗粒度越小,谱线强度越大,稳定性越好。为校正LIBS光谱基体效应的干扰,采用了样品研磨预处理和光谱数据预处理两种方法。将细长条状的C3和C5两个样品进行研磨,研磨后谱线的强度和稳定性有较大提升;分别研究了强度归一化、多元散射校正(MSC)以及两者结合对光谱进行处理的效果,三种光谱预处理均使谱线的稳定性得到显著提高。通过支持向量机(SVM)对Cu元素的定量结果进行了评估和对比,结果发现,采用研磨样品并结合强度归一化与MSC预处理得到的校正效果最优,最终使S1和S2两个待测样品的Cu元素预测相对误差(RE)分别降为1.745%和1.857%,预测均方根误差(RMSEP)降为0.020。该研究可为表面凹凸不平样品的LIBS检测提供一定的方法依据和参考。 相似文献
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可见近红外非成像光谱分析技术已被广泛用于土壤有机碳(SOC)含量估测,然而该技术的使用受土壤粗糙度的影响,对样本的前处理要求较高,导致模型的实用性受限。针对这一问题,以美国爱荷华州农田土壤为研究对象,使用成像及非成像光谱仪获取土壤样本研磨前后的可见近红外反射光谱,采用去包络线(CR)、吸光度变换(AB)、S-G平滑(SG)、标准正态变换(SNV)、多元散射校正(MSC)5种光谱预处理手段,利用偏最小二乘回归(PLSR)和支持向量回归(SVR)算法构建并对比土壤SOC光谱估算模型,探究利用成像光谱数据估测高粗糙度样本SOC含量的可行性。实验结果表明,使用成像光谱数据能够实现高粗糙度样本的SOC含量估算,而使用非成像光谱数据则无法估算高粗糙度样本的SOC含量;基于成像光谱数据建立的高粗糙度SOC最优PLSR估算模型R2能够达到0.739以及最优SVR估算模型R2为0.712,而基于非成像光谱数据建立的高粗糙度SOC最优PLSR和SVR估算模型R2仅仅分别为0.344和0.311。基于AB,SG,SNV和MSC这4种预处理手段之后的成像光谱数据建立的土壤样本研磨前的PLSR模型性能优于样本研磨之后建立的PLSR模型,而SVR模型性能正好相反。而对于非成像光谱数据来说,土壤样本研磨后建立PLSR和SVR模型精度总是强于样本研磨前建立的模型精度。对于这两种光谱数据和两个估算模型而言,不同的光谱预处理方法提高模型估算精度的能力不同。土壤样本研磨前后,基于成像光谱数据建立的PLSR和SVR模型性能均优于非成像光谱数据所构建的模型。成像光谱技术能够增强高粗糙度土壤样本可见近红外光谱与SOC的相关性,从而提高模型估算精度;能够克服土壤粗糙度的影响;为野外大尺度估测SOC含量提供了新的手段。 相似文献