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1.
A series of ethynyl and ethenyl end-capped imide resins were synthesised by the reaction of 9,9-bis(4-aminophenyl) fluorene
(BAF) with pyromellitic dianhydride (PMDA)3/3′, 4,4′-benzophenone tetracarboxylic acid dianhydride (BTDA)/2,2-bis(3,4-dicarboxy
phenyl) hexafluoropropane dianhydride (6F) and 3-ethynyl aniline/maleic anhydride. Structural characterisation was done by
infra red and elemental analysis. Thermal characterisation was done by differential scanning calorimetry and thermogravimetric
analysis. The decomposition temperatures of cured resins were above 200°C in nitrogen atmosphere. Char yield at 800°C ranged
from 59–65.5%. 相似文献
2.
A set of seven bituminous coal chars has been characterised by IR spectroscopy (FTIR), thermogravimetry (TG) and elemental analysis. FTIR study provided suitable information to establish differences between coal samples according to their chemical compositions. The reactivity of these samples was also studied and correlated with the coal parameters of mean vitrinite reflectance, fuel ratio and H/C ratio. The data suggest that reactivity as determined can be correlated with the mean vitrinite reflectance, fuel ratio and H/C ratio (0.90). The order of reactivity of samples were; Amasra (S1) (R m= 0.65)>Azdavay (S4) (R m=0.99)»Armutcuk (S2) (R m=0.81)»Acenta (S3) (R m=0.92)>Ac2l2k (S6) (R m=1.11) Cay (S5) (R m=1.03)>Sogutozu (S7) (R m=2.14). 相似文献
3.
在Ar气流中热处理KOH-煤焦制大比表面积活性炭 总被引:2,自引:1,他引:2
本文将煤焦与KOH混合,在Ar气流中进行低温、高温二次热处理,制得了比表面积为2918m2/g的活性炭。考查了操作条件对产品性能的影响,同时用X射线衍射分析研究了煤焦制活性炭过程中的结构变化特征 相似文献
4.
Curing of diglycidyl ether of bisphenol-A (DGEBA) with phosphorus containing amide amines i.e. bis[3(3’-aminobenzamido phenyl)]methyl
phosphine oxide (MB),bis[3(4’-aminobenzamido phenyl)]methyl phosphine oxide (PB), tris[3(3’-aminobenzamidophenyl)] phosphine
oxide (MT) and tris[3(4’-aminobenzamido phenyl)] phosphine oxide (PT)and conventionally used curing agent 4,4’-diaminodiphenyl
sulfone (D) was studied by DSC. The amines MB, PB, MT and PT were synthesised in the laboratory and were characterized by
determining elemental composition, melting point, and amine equivalent. Structural characterization was done by 1H-NMR and FTIR. The onset temperature of curing depended on the nucleophilicity of the amines and was in the orderMT≈MB<PT<PB<D.
The exothermic peak temperatures were in the orderD>PB>PT>MT≈MB. The char residue of cured epoxy resin was significantly higher
when phosphorus was incorporated in the cured network. Using mixed amine formulations based on amine D and P-containing amines
and the molar ratio of these amines could easily control the curing characteristics. A linear relationship between char yield
and P-content was observed in such formulations.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
5.
Pengcheng Li Jie Dai Yi Xu Qichao Ran Yi Gu 《Journal of polymer science. Part A, Polymer chemistry》2019,57(14):1587-1592
A difunctional benzoxazine (coPh‐apa) with a conjugated alkyne group is synthesized by the oxidative coupling reaction from a monocycle‐benzoxazine (Ph‐apa) containing an alkyne group. A model compound, 1,4‐diphenylbutadiyne (coPa), is used to study the curing reaction process of coPh‐apa by DSC, Fourier transform infrared spectroscopy, and 13C NMR, and the results suggest that the conjugated alkyne groups are involved in the crosslinking reaction via the trimerization reaction of the conjugated alkynyl groups and the Diels–Alder reaction. Furthermore, thermal properties of the polybenzoxazine are studied by dynamic thermomechanical analysis and thermogravimetric analysis. A glass‐transition temperature (Tgs) of as high as 412 °C and a char yield of 75.6% at 800 °C under nitrogen are obtained with the aid of the conjugated alkyne groups. Its excellent heat resistance dominates most thermosetting resins and will serve for heat shields. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1587–1592 相似文献
6.
以麦秆和稻壳生物质为研究对象,在不同的热解温度、热解速率以及蒸汽活化温度条件下制备了生物质焦,采用比表面积与孔隙度分析仪测定生物质焦的比表面积和孔隙结构参数。利用固定床吸附装置,研究了热解温度、热解速率、活化温度和模拟烟气中SO2和NO浓度等因素对生物质焦吸附SO2和NO性能的影响。结果表明,蒸汽活化可以显著提高生物质焦的BET比表面积、D-R比表面积、D-R微孔容积和总孔容,降低其平均孔径,并显著增加蒸汽活化生物质焦对SO2与NO吸附的起始穿透时间和吸附量。快速热解下制得的蒸汽活化焦对SO2和NO的吸附效果优于慢速热解,热解温度为873 K的蒸汽活化焦的吸附性能明显好于热解温度为673与1 073 K的蒸汽活化焦。在973~1 173 K下,随着蒸汽活化温度的提高,蒸汽活化生物质焦对SO2和NO的吸附量呈现先上升后下降的趋势。随着模拟烟气中SO2与NO浓度的降低,蒸汽活化生物质焦对SO2与NO吸附的起始穿透时间延长,但相应的SO2和NO吸附量下降。在873 K、快速热解和1 073 K条件下制得的蒸汽活化麦秆焦对SO2和NO吸附量最大,其值分别为109.02和21.77 mg/g。 相似文献
7.
A significant part of organic carbon found on the earth is deposited as fossil organic matter in the lithosphere. The most important reservoir of carbon is shale rocks enriched with organic matter in the form of kerogen created during diagenesis. The purpose of this study was to analyze whether the bacterial communities currently inhabiting the shale rocks have had any impact on the properties and type of kerogen. We used the shale rock located on the Fore-Sudetic Monocline, which is characterized by oil-prone kerogen type II. We were able to show that shale rock inhabited by bacterial communities are characterized by oxidized and dehydrated kerogen type III (gas-prone) and type IV (nonproductive, residual, and hydrogen-free). Bacterial communities inhabiting shale rock were dominated by heterotrophs of the Proteobacteria, Firmicutes, and Actinobacteria phyla. Additionally, we detected a number of protein sequences in the metaproteomes of bacterial communities matched with enzymes involved in the oxidative metabolism of aliphatic and aromatic hydrocarbons, which may potentially contribute to the postdiagenetic oxidation and dehydrogenation of kerogen. The kerogen transformation contributes to the mobilization of fossil carbon in the form of extractable bitumen dominated by oxidized organic compounds. 相似文献
8.
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10.
合成气制低碳烯烃用Fe/AC催化剂的制备及性能表征 总被引:11,自引:1,他引:11
研究了以活性炭(AC)作为载体制备的铁基催化剂,通过对不同铁盐、活性炭和助剂的筛选,研制出对合成气转化为低碳烯烃具有高活性和高选择性的催化剂.对反应前及反应过程中催化剂体相结构的XRD测试结果表明,Fe-Cu-K/AC催化剂在反应前主要由α-Fe,Fe3O4和Cu0组成,经合成气反应后主要由α-Fe,Fe5C2,Fe7C3,Cu0和K2O组成.Fe-Mn-K/AC催化剂的晶体结构主要以Fe嵌入MnO中形成的(Fe,Mn)O结构存在.实验中得出的α-Fe,FexCy及(Fe,Mn)O与激光热解法制备的催化剂的的晶体结构相似.对催化剂的制备方法进行了筛选,考察了不同助剂Cu,Mn,Si和K等元素对催化剂性能的影响.结果表明,以草酸铁为铁源,椰壳炭为载体制备的Fe-Mn-K/AC催化剂的催化效果最佳,在空速600h-1,压力1.5MPa和温度320℃条件下,CO转化率可达97.4%,C=2~C=4选择性可达68.0%. 相似文献