2024/9/211TGA的文献阅读 2024/9/2121234目录CONTENTS热重分析在跟踪监测镉离子在环境中的浓度用到的吸附剂的应用热重分析在表征PVD氧化物涂层中的应用热重分析在确定生物柴油降解程度中的应用热重分析在聚甲醛POM解聚反应动力学中的应用 2024/9/213热重分析在跟踪监测镉离子在环境中的浓度用到的吸附剂的应用 2024/9/214Article 1. Solid phase extraction and trace monitoring of cadmium ions in environmental water and food samples based on modified magnetic nanoporous silica 1.文献背景已研制出的一种新方法使用pyr-idine-functionalized微量镉离子的分离/预磁纳米多孔硅材料(称为Py-Fe3O4@MCM-41)作为一种新的磁性吸附剂及其通过火焰原子吸收光谱法(FAAS)测定Py-Fe3O4@MCM-41吸着剂的表征是通过热重分析、差热分析、透射电子显微镜、傅里叶变换红外光谱法和x射线衍射。
改性后的Fe3O4 @MCM-41可以很容易地通过应用一个外部磁场来分离水溶液中的镉离子Omidi F, Behbahani M, Bojdi M K, et al. Solid phase extraction and trace monitoring of cadmium ions in environmental water and food samples based on modified magnetic nanoporous silica[J]. Journal of Magnetism and Magnetic Materials, 2015, 395: 213-220. 2024/9/2152.Simple Introduction Magnetic nanoparticles have been intensively in-vestigated in recent years In the present study, the synthesized modified magnetic nanoporous silica (Py-Fe3O4@MCM-41) was used for selective solid phase extraction and ultra-trace determination of cadmium ions in environmental water and food samples. The mentioned sorbent was characterized using transmission electron microscopy (TEM), thermal analysis (TGA/DTA), Fourier transform infrared spec-trometery (FT-IR), and X-ray diffraction (XRD).Omidi F, Behbahani M, Bojdi M K, et al. Solid phase extraction and trace monitoring of cadmium ions in environmental water and food samples based on modified magnetic nanoporous silica[J]. Journal of Magnetism and Magnetic Materials, 2015, 395: 213-220. 2024/9/216 2024/9/217Now,I want to talk about extraction procedure Fig. 2. A scheme to illustrate the extraction procedure 2024/9/218TGA and DTA curves •A weight loss occurred between 200 °C and 600 °C which is accompanied with exother-mic peaks at 400 °C and 500 °C in DTA curve,is corresponded to the oxidative decomposition of organic part of N[3(triethoxysilyl)propyl]isonicotinamide(TPI).Further more,according to thermal analysis,the prepared composite is stable up to 200 °C.According to the weight of lossin TGA curve,the amount of pyr-idine introduced into Fe3O4@ MCM-41is1.6mmolg •In conclusion, this pyridine functionalized magnetic mesoporous silica is a pro- mising adsorbent for heavy metal detection in real samples. 2024/9/219热重分析在表征PVD氧化物涂层中的应用 2024/9/2110Article 2 Role of PVD oxide coatings on HK40 cast steel during short and long exposure to C-rich atmospheres1.文献背景（PVD工艺）真空镀膜是在真空中将钛、金、石墨、水晶等金属或非金属、气体等材料利用溅射、蒸发或离子镀等技术， 在基材上形成薄膜的一种表面处理过程 。
真空镀膜技术中经常使用的方法主要有：蒸发镀膜（包括电弧蒸发、电子枪蒸发、电阻丝蒸发等技术）、溅射镀膜（包 括直流磁控溅射、中频磁控溅射、射频溅射等技术），这些方法统称物理气相沉积 法Salas O, Melo-Máximo D V, Oseguera J, et al. Role of PVD oxide coatings on HK40 cast steel during short and long exposure to C-rich atmospheres[J]. Materials Characterization, 2013, 83: 58-67. 2024/9/21113.主要的实验Fig. 1 – (a) and (b) SE views of the HK40 steel structure prior to exposure to the C-rich atmosphere. Below, Cr and Fe compositional profiles along the line shown in (b).Fig. 2 – Typical SE views of the Cr/Cr oxide coatings prior to exposure to the C-rich atmosphere. (a) Low magnification view and(b) HRSEM BSE image from the surface. 2024/9/2112Fig. 8 – SE cross section views of the: (a) uncoated and (b) and(c) coated substrates after exposure for 50 h to CH4 at 1073 K. 2024/9/2113Thermogravimetric AnalysisFig. 4 – TG curves from exposure of the uncoated and coated samples to CH4 at 1073 K for 60 min. 2024/9/2114 2024/9/21154.结论1.异构树突结构合金裸基板形成的腐蚀产物有明显影响的位置和类型,可能是因为通过这个结构组件有不同的扩散。
2.残余的存在渗碳气氛中的氧含量有明显影响阶段形成的类型在暴露于c的气氛,尤其是在裸基板.3.目前的发现证实的保护作用Cr / Cr2O3涂料,虽然很明显,提高他们的保护行为需要更多的工作 2024/9/2116热重分析在确定生物柴油降解程度中的应用 2024/9/2117Article 3.Thermogravimetric analysis as a rapid and simple method to determine the degradation degree of soy biodiesel1.文献背景全球生物柴油的使用越来越普遍这种能源有几个好处促进其被接纳;生物可再生性,非毒性和生物降解其液体状态允许其在柴油发动机目前使用流通的不需要重大改变生物柴油的一个缺点是它对氧化降解敏感一种现象,影响生物柴油的质量一般报道的退化机制有:氧化、光氧化和酶氧化等一个简单的方法来研究和改善生物柴油的氧化稳定性就是对它进行测量Vega-Lizama T, Díaz-Ballote L, Hernández-Mézquita E, et al. Thermogravimetric analysis as a rapid and simple method to determine the degradation degree of soy biodiesel[J]. Fuel, 2015, 156: 158-162. 2024/9/21182.实验分析Fig. 1 also contains the derivative of the thermogravimetric curve (dotted line). This curve helps to determine the temperature at which there is the maximum rate of change of thermal decomposition(dm/dTmax) of biodiesel, which is located at 213℃ 2024/9/2119 2024/9/2120Fig. 2. TGA curve of oxidized biodiesel and its derivative. Oxidation conditions:areaof153.9cm2(A3),temperature120C,exposuretime24h. 2024/9/2121 2024/9/2122结论1.基于剩余热重曲线的质量确定生物柴油的氧化程度进行研究的一个方法。
剩余质量在294度得到的生物柴油商业成品油TGA曲线,表明它可以用作衡量它的氧化程度2.运动粘度的结果,紫外光谱和核磁共振氢谱显示与TGA剩余的质量一致因此,热重分析是一种有效的和简单的方法来确定生物柴油退化程度 2024/9/2123热重分析在聚甲醛POM解聚反应动力学中的应用 2024/9/2124Article 4. Kinetics of depolymerization of paraformaldehyde obtained bythermogravimetric analysis1.文献背景甲醛，化学式为HCHO，是最简单的产品之一，由甲醇部分氧化得来，是最活性有机物质之一;因此,在许多反应是很重要的,例如在聚合过程作为原材料2012年甲醛全球产量达到4640万吨甲醛通常是在水溶液中商业化的产品,稳定甲醇以避免其聚合,在固体形态的聚合物:多聚甲醛(PF)和8 - 100甲醛单位或聚甲醛均聚物(POM-H)更高的分子重量,包含多达500甚至更多单体的单位Grajales, Edwing J., Edwin A. Alarcón, and Aída L. Villa. "Kinetics of depolymerization of paraformaldehyde obtained by thermogravimetric analysis." Thermochimica Acta 609 (2015): 49-60.CH3OH(g) HCHO(g)＋H2(g) 2024/9/21252.实验分析2.1Characterization of materialsPFP and PFS were characterized by X-ray diffraction (XRD),infrared spectroscopy, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). XRD was carried out in a Bruker diffractometer D8 ADVANCE with CuKα radiation. For Fourier transform infrared spectroscopy (FTIR), pellets, prepared with controlled amounts of PF and KBr, were measured at room temperature in a SpectrumOne PerkinElmer instrument with a deuterated tri-glycine sulfate pyroelectric (DTGS) detector, at frequencies from 4000 to 400 cm with a resolution of 4 cm .DSC were obtained in a TA instrument model Q100 under nitrogen atmosphere; samples at room temperature were cooled to –80℃ at 20 ℃/min, and the analyses were carried from –80 ℃to 300℃ using a heating rate of 5℃/ min. The TGA experiments were carried out by non-isothermal method using a Q-500 TA instruments;the samples, with mass between 10 and 15 mg, were heated at three different heating rates b = 5, 7.5 and 10℃/min, with a continuous nitrogen flow of 40 mL/min from 20 to 300℃ 2024/9/21262.2 Characterization of materialsFig. 1. XRD of paraformaldehyde samples. (a) PFP and (b) PFS.Fig. 2. FTIR analysis of PF samples (a) PFP and (b) PFS. *Unidentified bands 2024/9/2127Fig. 3. Second derivative of FTIR curves for (a) PFP and (b) PFS. Curve (a) with 1.5 units vertical offset.Fig. 4. Effect of the heating rate on the decomposition of paraformaldehyde. (a) PFP,and (b) PFS. 2024/9/2128Fig. 5. DTG curves of the decomposition of PF. (a) PFP, and (b) PFS.Fig. 6. TGA and DSC analyses of PF samples with heating rate of 5℃ /min. (a) PFP,inset: DSC signal multiplied by 10, and (b) PFS. 2024/9/2129结论•1 这项研究显示了TGA的多功能性评估特征的影响，当聚合物作为反应物，它在其解聚动力学可以影响获得的单体在之后的反应步骤的反应性。
•2 两个来源的解聚作用动力学的甲醛聚合物在TGA恒定升温速率的实验中有不同的行为多聚甲醛粉分解发生在一个单一的一步Avrami-Erofeyev(A2)模型活化能为31.7 kJ mol-1,和多聚甲醛小球显示两个同时分解模型:几何收缩(R3)和Avramy-Erofeyev(A2)的激活能量分别为105.4和48.4 kJmol-1•3 粉末状的多聚甲醛PFP较颗粒状的PFS在生产甲醛的应用中有更好的效率与实用性 2024/9/2130参考文献[1] Omidi F, Behbahani M, Bojdi M K, et al. Solid phase extraction and trace monitoring of cadmium ions in environmental water and food samples based on modified magnetic nanoporous silica[J]. Journal of Magnetism and Magnetic Materials, 2015, 395: 213-220.[2] Salas O, Melo-Máximo D V, Oseguera J, et al. Role of PVD oxide coatings on HK40 cast steel during short and long exposure to C-rich atmospheres[J]. Materials Characterization, 2013, 83: 58-67.[3] Vega-Lizama T, Díaz-Ballote L, Hernández-Mézquita E, et al. Thermogravimetric analysis as a rapid and simple method to determine the degradation degree of soy biodiesel[J]. Fuel, 2015, 156: 158-162.[4] Grajales, Edwing J., Edwin A. Alarcón, and Aída L. Villa. "Kinetics of depolymerization of paraformaldehyde obtained by thermogravimetric analysis." Thermochimica Acta 609 (2015): 49-60. 2024/9/2131EndThankyou 。