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1.
Hybrid ion exchangers (HIXs) containing fine Cu2O and Cu0 particles were subjected to thermal analysis in order to determine their hygroscopic water content (with regard to their anomalously low porosity) and to determine the effect of the oxidation state of the copper atom in the deposit on the thermal properties of composite materials. Commercially available anion exchangers, Amberlite IRA 900Cl (macroreticular, M) and Amberlite IRA 402OH (gel-like, G), were used as supporting materials. M/Cu2O, G/Cu2O, M/Cu and G/Cu, containing 4.3–8.4 wt% Cu, were subjected to thermal analysis under respectively air and N2. TG/DTG curves revealed that dry M/Cu and G/Cu contained as little as 7.2% and 4.3% hygroscopic water, while M/Cu2O and G/Cu2O contained respectively 10.6% and 9.4% (Cu0 was a stronger water repellent than Cu2O). The oxidation state of the copper atom in the deposit was found to affect the amount of the forming char, and also Cu0 was found to contribute to the formation of more char than in the pyrolysis of the pure resin (the anion exchanger with no copper deposit). Under air the two kinds of particles transformed into CuO, while under N2 metallic copper and char (from the resin phase) made up the solid residue. This means that in the pyrolysis of the HIXs the inorganic phase participated in char formation and it also transformed itself (undergoing reduction when possible). The above findings provide a basis for in-depth research aimed at the innovative use of copper-containing HIXs and at obtaining usable composite materials with a designed (organic-inorganic) composition.  相似文献   
2.
The film thickness plays an important role in the performance of materials applicable to different technologies including chemical sensors, catalysis and/or energy materials. The relationship between the surface and volume of the functional layers is key to high performance evaluations. Here we demonstrate the thermophoretic deposition of different thicknesses of the functional layers designed using flame combustion of tin 2-ethylhexanoate dissolved in xylene, and measurement of thickness by scanning electron microscopy and focused ion beam. The parameters such as spray fluid concentration (differing Sn2+ content), substrate-nozzle distance and time of the spray were considered to investigate the layer growth. The results showed ≈ 23, 124 and 161 μm thickness of the SnO2 layer after flame spray of 0.1, 0.5 M and 1.0 M tin 2-EHA-Xylene solutions for 1200 s. While Sn2+ concentration was 0.5 M for all the flame sprays, the substrates placed at 250, 220 and 200 mm from the flame nozzle had layer thicknesses of 113, 116 and 132 µm, respectively. Spray time dependent thickness growth showed a linear increase from 8.5 to 152.1 µm when the substrates were flame sprayed for 30 s to 1200 s using 0.5 M tin 2-EHA-Xylene solutions. Changing the dispersion oxygen flow (3–7 L/min) had almost no effect on layer thickness. Layers fabricated were compared to a model found in literature, which seems to describe the thickness well in the domain of varied parameters. It turned out that primary particle size deposited on the substrate can be tuned without altering the layer thickness and with little effect on porosity. Applications depending on porosity, such as catalysis or gas sensing, can benefit from tuning the layer thickness and primary particle size.  相似文献   
3.
Silicon oxynitrides (SiOxNy) have many advantageous properties for modern ceramic applications that justify a development of their new and efficient preparation methods. In the paper, we show the possibility of preparing amorphous SiOxNy-based materials from selected liquid organosilicon compounds, methyltrimethoxysilane CH3Si(OCH3)3 and methyltriethoxysilane CH3Si(OC2H5)3, by a convenient spray pyrolysis method. The precursor mist is transported with an inert gas or a mixture of reactive gases through a preheated tube reactor to undergo complex decomposition changes, and the resulting powders are collected in the exhaust filter. The powders are produced in the tube at temperatures of 1200, 1400, and 1600 °C under various gas atmosphere conditions. In the first option, argon Ar gas is used for mist transportation and ammonia NH3 gas serves as a reactive medium, while in the second option nitrogen N2 is exclusively applied. Powder X-Ray Diffraction (XRD) results confirm the highly amorphous nature of all products except those made at 1600 °C in nitrogen. SEM examination shows the spheroidal particle morphology of powders, which is typical for this method. Fourier Transform Infrared (FT-IR) spectroscopy reveals the presence of Si–N and Si–O bonds in the powders prepared under Ar/NH3, whereas those produced under N2 additionally contain Si–C bonds. Raman spectroscopy measurements also support some turbostratic free carbon C in the products prepared under nitrogen. The directly determined O- and N-contents provide additional data linking the process conditions with specific powder composition, especially from the point of view of oxygen replacement in the Si–O moieties formed upon initial precursor decomposition reactions by nitrogen (from NH3 or N2) or carbon (from the carbonization of the organic groups).  相似文献   
4.
中药废弃物的能源化利用策略   总被引:2,自引:0,他引:2  
龙旭  郭惠  靳如意  唐于平  高静  孟庆华  张拴 《中草药》2019,50(7):1505-1514
生物质能具有可再生、资源丰富、碳中性、环境友好等优点,将典型生物质的中药废弃物高附加值转化为能源,循环应用于工业生产,既可实现废弃物的处理转化,又能达到取代化石燃料、节能降耗、增加企业利润的目的。分析中药废弃物能源化的利用策略(直接燃烧、发酵制沼气和乙醇、热解气化等),为后续深入探索和开发中药废弃物的能源高值化利用模式及拓展资源的利用途径和层次提供参考。  相似文献   
5.
目的以机油为分散剂高温热解人发后发现新型纳米碳点,通过动物实验评价了该碳点的生物效应。方法利用高温热解法对人发和机油进行炭化,对炭化产物进行萃取、过滤分离和透析得到一种具有水溶性的新型物质碳点,并命名为JYRF-CDs。利用透射电子显微镜(TEM)、高分辨透射电子显微镜(HR-TEM)、紫外-可见分光光谱、傅里叶变换红外光谱、荧光光谱、X射线光电子能谱分析(XPS)等多种方法对JYRF-CDs进行表征,利用小鼠单核巨噬细胞RAW264.7细胞进行CCK-8毒性实验来评价JYRF-CDs的安全性,并通过小鼠耳肿胀实验和小鼠醋酸扭体实验对JYRF-CDs的生物效应进行评价。结果 JYRF-CDs外形为类球形,粒径均匀分布在1.8~3.6 nm,晶格间距为0.219 7 nm。细胞毒性实验结果显示,JYRF-CDs具有低毒性,动物实验结果表明JYRF-CDs具有良好的抗炎和镇痛作用。结论首次以机油为分散剂高温热解人发后发现一种全新的碳点JYRF-CDs,以JYRF-CDs为突破口,更加明确阐释以机油为分散剂高温热解人发后炭化产物具有生物效应的物质基础,为纳米类成分的研究提供了一种新方法。  相似文献   
6.
Extruded polystyrene (XPS) is a thermal insulation material extensively applied in building systems. It has attracted much attention because of outstanding thermal insulation performance, obvious flammability shortcoming and potential energy utilization. To establish the reaction mechanism of XPS’s pyrolysis, thermogravimetric experiments were performed at different heating rates in nitrogen, and multiple methods were employed to analyze the major kinetics of pyrolysis. More accurate kinetic parameters of XPS were estimated by four common model-free methods. Then, three model-fitting methods (including the Coats-Redfern, the iterative procedure and masterplots method) were used to establish the kinetic model. Since the kinetic models established by the above three model-fitting methods were not completely consistent based on different approximations, considering the effect of different approximates on the model, the reaction mechanism was further established by comparing the conversion rate based on the model-fitting methods corresponding to the possible reaction mechanisms. Finally, the accuracy of the above model-fitting methods and Particle Swarm Optimization (PSO) algorithm were compared. Results showed that the reaction function g(α) = (1 − α)−1 − 1 might be the most suitable to characterize the pyrolysis of XPS. The conversion rate calculated by masterplots and PSO methods could provide the best agreement with the experimental data.  相似文献   
7.
目的:推断并验证大黄、地榆、牡丹皮3味中药炒炭的热解反应机制,进一步完善这3味中药炒炭研究的理论。方法:采用模式函数法中的单个扫描速率的不定温法(Coats-Redfern模型与Achar模型)推断大黄、地榆、牡丹皮3味中药炒炭过程中热解反应的机理函数,通过比较转化率(α)理论值、实验值与1/T的热分析曲线对机理函数进行验证。结果:积分形式表达式能更较好地描述大黄、地榆、牡丹皮3味中药炒炭热解的反应机制,三者的炒炭热解机理函数分别为9号机理函数积分形式g(α)=[(1-α)-1/3-1]2,2号机理函数积分形式g(α)=α+(1-α)ln(1-α),9号机理函数积分形式g(α)=[(1-α)-1/3-1]2。结论:3味中药炒炭的热解反应机制均属于反应扩散,转化率理论值与实验值存在一定的差异,运用热分析动力学方法只是尽可能地模拟这3味中药的炒炭热解反应过程。  相似文献   
8.
本研究采用固体热解装置并引入同步辐射真空紫外光电离质谱技术(SVUV-PIMS)对补骨脂素的热解产物进行检测,结合量子化学计算其初始热解路径,研究补骨脂素的热解动力学。结果表明,SVUV-PIMS检测到3种热解产物,分别为CO,C9H6O,C10H6O2;通过理论计算出补骨脂素3种可能的裂解途径,其中,补骨脂素主要的初级分解路径是脱CO,主要二级分解反应为脱CO产物的脱CO反应。  相似文献   
9.
借助化学分析和FTIR光谱分析对我国煤化程度不同的18 种煤中官能团的研究表明:煤中官能团含量与煤化程度有关;煤中羧基、羟基及醚键等其他含氧官能团的含量与热解生成物CO2、H2O 和CO 的产率有关,脂肪—CH 的含量与甲烷和焦油的产率相关联,芳香—CH 的含量与热解半焦产率有关。煤的热解生成物主要是煤中官能团的断裂所致。  相似文献   
10.
目的探讨瞬时受体电位香草素受体4型通道蛋白(TRPV4)抑制剂HC067047对小鼠膝骨关节炎软骨组织的影响。 方法将30只小鼠均分为假手术组、模型组、HC067047组。假手术组仅切开右侧膝关节髌韧带内侧皮肤,不予处理膝关节囊内结构;模型组、HC067047组手术切除小鼠板股韧带及内侧半月板前角以构建膝骨关节炎,分别用生理盐水、HC067047每天10 mg/kg灌胃。qRT-PCR检测各组小鼠软骨组织中TRPV4 mRNA表达水平。番红固绿染色评估关节软骨受损程度,HE染色分析膝关节软骨下骨的骨量变化。Western blotting检测各组软骨组织中细胞焦亡标志蛋白TRPV4、Caspase-1、核苷酸结合寡聚化结构域样受体家族热蛋白结构域蛋白3(NLRP3)、凋亡相关斑点样蛋白(ASC)、GSDMD-N蛋白水平;ELISA、Western blotting分别检测血清、软骨组织中炎症因子水平。 结果与假手术组比较,模型组TRPV4、NLRP3、ASC、Caspase-1、GSDMD-N、IL-1β、IL-18水平显著升高(P<0.05)。与模型组比较,HC067047组NLRP3、ASC、Caspase-1、GSDMD-N、IL-1β、IL-18水平显著降低(P<0.05)。HC067047能明显改善关节软骨形态及降低骨关节炎受损程度,并能维持软骨下骨的骨量。 结论TRPV4抑制剂HC067047能抑制软骨组织细胞焦亡,改善膝骨关节炎小鼠关节软骨的退变。  相似文献   
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