共查询到20条相似文献,搜索用时 218 毫秒
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为了研究六次甲基四胺对芘热缩聚的影响,分别以芘或芘与六次甲基四胺的混合物为原料在480℃进行热缩聚反应,并利用MALDI-TOF-MS、13C-NMR、FT-IR、元素分析和热台显微镜对热缩聚产物的组分、结构进行分析表征。测试结果表明,添加六次甲基四胺后,芘单体能够完全转化为低聚体,热缩聚产物中的碳元素含量和氯仿不溶物含量升高。此外,元素分析结果显示六次甲基四胺在芘热缩聚过程中(400℃)能够与芘相结合,随着反应温度的提高(480℃),大部分六次甲基四胺从反应体系中排出。这些研究结果说明六次甲基四胺对于芘的热缩聚反应具有明显的催化作用。 相似文献
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间苯二酚六次甲基四胺络合物(PY)对白炭黑补强天然胶的影响 总被引:2,自引:0,他引:2
采用平衡溶胀法、力学性能以及老化性能,表征PY对白炭黑补强天然胶的影响。结果表明PY加强了橡胶-白炭黑界面的相互作用,使体系综合力学性能显著提高,加入了PY的硫化胶耐老化性也得到改善。 相似文献
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六次甲基四胺、邻苯二甲酸、咪唑和Cu(Ⅱ)配合物的合成及单晶培养 总被引:1,自引:0,他引:1
六次甲基四胺(hmt)、邻苯二甲酸与咪唑(im)和金属离子配位可形成一系列的配合物,本文重点介绍了六次甲基四胺、邻苯二甲酸与Cu(Ⅱ)(im)4(NO3)2以乙醇-水为溶剂,采用常温溶剂蒸发法合成标题配合物及培养出其单晶. 相似文献
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以Ti(SO4)2为前驱物,尿素为沉淀剂,六亚甲基四胺为掺杂剂,采用水热沉淀法制得了锐钛矿型掺氮TiO2纳米粉体。采用XRD对制备的掺氮氧化钛结构进行了表征,探讨了水热合成温度和体系的pH值对水热反应的影响,并对其可见光照射下的光催化性能进行了测试。结果表明,水热反应温度高于220℃时氮可掺进TiO2晶体中,且温度越高,掺氮量越高;水热反应温度为840℃、尿素/硫酸钛摩尔比为4:1时,氮掺杂TiO2粉体可见光催化活性最强,在波长不低于400nm的可见光作用下,对亚甲基蓝的4h降解率达81.03%。 相似文献
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煤层气中CH4/N2分离工艺研究进展 总被引:5,自引:1,他引:4
介绍了近期针对煤层气中CH4/N2体系的分离工艺研究进展。论述目前应用于CH4/N2体系分离的主要方法,包括低温精馏、变压吸附和膜分离工艺,探讨了各种方法在不同工艺条件下的分离效果,以及在实际应用中的特点和技术上的改进,展望了未来的研究发展方向。 相似文献
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Junko Hatori Yasumitsu Matsuo Masaru Komukae Seiichiro Ikehata Toshio Osaka 《Ferroelectrics Letters Section》2002,29(1):37-42
Proton NMR line width and spin-lattice relaxation time T 1 for the ferroelectric (CH 3 ) 2 NH 2 H 2 AsO 4 have been measured at the temperature range between 77 K and 300 K. The temperature dependence of T 1 is well described by the expressions based on rotation of the methyl group using the value of activation energy E a = 99 meV and elementary correlation time τ0 = 1.5 ×10 -13 sec. Moreover, a sharp dip of T 1 near ferrroelectric phase transition temperature ( T c = 274.5 K) results from the ordering of protons. In addition, the temperature dependence of T 1 deviates from the expression for molecular rotation above around 200 K. It is deduced that the deviation is caused by the suppression of some kind of proton motion. 相似文献
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采用变压吸附分离的方法分离CH4/N2体系时,活性炭作为一种主要的吸附剂受到广泛研究.本文采用10-4-3模型计算得出,孔径为0.7~2.0nm的活性炭微孔对CH4/N2体系分离的效果最好;同时利用扩展Langmuir方程通过拟合4种活性炭对CH4/N2的吸附等温线,计算得出分离系数;最后讨论样品的孔径分布与分离系数的关系,进一步证明了10-4-3模型的计算结果. 相似文献
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Accumulation of greenhouse gases in the atmosphere is responsible for increased global warming of our planet. The increasing concentration of carbon dioxide mainly from flue gas, automobile and landfill gas (LFG) emissions are major contributors to this problem. In this work, CO2, CH4 and N2 adsorption was studied on Ceca 13X zeolite by determining pure and binary mixture isotherms using a constant volume method and a concentration pulse chromatographic technique at 40 and 100°C. The experimental data were then compared to the predicted binary behaviour by extended Langmuir model. Results showed that the extended Langmuir theoretical adsorption model can only be applied as an approximation to predict the experimental binary behaviour for the systems studied. Equilibrium phase diagrams were obtained from the experimental binary isotherms. For these systems, the integral thermodynamic consistency tests were also conducted. It was found that Ceca 13X exhibits large CO2/CH4 and CO2/N2 selectivity and could find application in landfill gas purification, CO2 removal from natural gas and CO2 removal from ambient air or flue gas streams. © 2011 Canadian Society for Chemical Engineering 相似文献
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Feifei Zhang Hua Shang Bolun Zhai Xiaomin Li Yingying Zhang Xiaoqing Wang Jinping Li Jiangfeng Yang 《American Institute of Chemical Engineers》2023,69(6):e18079
A robust aluminum-based metal–organic framework (Al-MOF) MIL-120Al with 1D rhombic ultra-microporous was reported. The nonpolar porous walls composed of para-benzene rings with a comparable pore size to the kinetic diameter of methane allow it to exhibit a novel thermodynamic-kinetic synergistic separation of CH4/N2 mixtures. The CH4 adsorption capacity was as high as 33.7 cm3/g (298 K, 1 bar), which is the highest uptake value among the Al-MOFs reported to date. The diffusion rates of CH4 were faster than N2 in this structure as confirmed by time-dependent kinetic adsorption profiles. Breakthrough experiments confirm that this MOF can completely separate the CH4/N2 mixture and the separation performance is not affected in the presence of H2O. Theoretical calculations reveal that pore centers with more energetically-favorable binding sites for CH4 than N2. The results of pressure swing adsorption (PSA) simulations indicate that MIL-120Al is a potential candidate for selective capture coal-mine methane. 相似文献
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为了有效地捕集焦炉气及煤层气中的甲烷,提出了一种新型捕集技术:吸收-吸附组合方法,该方法通过把ZIF-8分散到乙二醇水溶液中形成悬浮浆液,实现对甲烷组分的捕集。首先测定了甲烷、氮气和氢气在浆液中的吸收-吸附容量,得出吸着量大小的顺序为CH4> N2> H2,然后对CH4/H2和CH4/N2的混合气进行吸着平衡研究,发现浆液均能有选择性地吸着甲烷。对浆液中回收的ZIF-8材料进行XRD表征,分析证明在整个吸着过程中ZIF-8结构没有发生变化并且ZIF-8/乙二醇-水浆液能重复利用。 相似文献