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21.
有机硅及其改性聚合物膜用于有机溶剂水溶液的渗透汽化分离 总被引:1,自引:0,他引:1
采用室温固化硅橡胶及其它三种改性硅氧烷聚合物制成渗透汽化膜,分离丙酮(A),丁酮(B)、乙醇(E)及异丙醇(P)等有机物的水溶液。结果表明,随着透过温度提高、透量成指数关系增大,但对分离系数影响甚小。透量大小顺序为A>B>E>P,分离系数大小顺序为A>B>P>E,当膜材料中(CH_3)_2SiO链节含量由70%上升到100%时,有机物的透量及分离系数同时增加。 相似文献
22.
Acylation of heteroatoms (O, N and S) with acetyl chloride based on the use of a catalytic amount of the moisture stable, inexpensive ZrOCl2·8H2O, proceeds efficiently producing the corresponding acylated products in excellent yields. 相似文献
23.
Decomposition of Toluene and Acetone in Packed Dielectric Barrier Discharge Reactors 总被引:2,自引:0,他引:2
Chung-Liang?ChangEmail author Tser-Sheng?Lin 《Plasma Chemistry and Plasma Processing》2005,25(3):227-243
The influences of TiO2 catalytic material and glass pellet packing on the decomposition efficiency of toluene and acetone in air by dielectric barrier discharge (DBD) reactors were experimentally investigated in this study. The effects of both packing materials on the formation of byproducts such as CO and CO2 were also evaluated. Experimental results indicate that the introduction of glass materials into the plasma zone of a wire-tube reactor would improve the decomposition efficiency of toluene and acetone compared to a nonpacked reactor. The apparent decomposition rate constant of a glass packed-bed reactor was 4.5–4.8 times greater than that of a nonpacked reactor. The results also indicate that the decomposition rate constant of toluene was approximately 2.6 times higher than that of acetone no matter which type reactor was utilized. The application of TiO2 coated pellets in DBD reactors will enforce the hydrocarbon byproducts to further be oxidized to CO2, notwithstanding, it will not significantly improve the performance of the reactors in the decomposition of toluene and acetone, and in the formation of CO. The results show that the best selectivity of CO2 for acetone decomposition in a TiO2 coated pellets packed-bed reactor was approximately 40% higher than that in a glass packed-bed reactor. 相似文献
24.
Biswanath Das Maddeboina Krishnaiah Keetha Laxminarayana K. Ravinder Reddy 《Journal of molecular catalysis. A, Chemical》2007,270(1-2):284-288
Sulfated zirconia has been employed as an efficient recyclable catalyst for the preparation of various β-acetamidoketones or esters at room temperature. The process involves the one-pot multicomponent reactions of aromatic aldehydes, enolizable ketones or β-ketoesters and acetonitrile in the presence of acetyl chloride. 相似文献
25.
《Journal of Coordination Chemistry》2012,65(18):3180-3188
Diferrocenylmethane (1) and 2-acetyl(diferrocenyl)methane (2) were synthesized and characterized by elemental analysis, FT-IR, and NMR. The molecular structures of 1 and 2 were determined using X-ray single crystal diffraction. The effect of acetyl group on electronic communication between two ferrocenyl units of 2 was investigated through cyclic voltammetry and density functional theory calculation. The acetyl did not influence electronic communication between two ferrocenyl units. The key factor that effected electronic communication of carbon-bridged diferrocenyl derivatives was charge density of the bridged carbon. 相似文献
26.
J. Mark Parnis Kaitlynn A. King Matthew G. K. Thompson 《Journal of mass spectrometry : JMS》2013,48(11):1224-1231
The chemistry of ionized acetone:Ar mixtures under varied ionizing electron density conditions has been studied using matrix‐isolation techniques. Gaseous acetone diluted in excess argon gas was subjected to electron bombardment with 300 eV electrons at currents between 20 and 200 μA. Linear wire ‘pin’ and metal ‘plate’ electron collector geometries were employed, allowing a wide range of electron density conditions to be explored. The products of subsequent reaction processes were matrix isolated and analyzed by Fourier transform infrared absorption spectroscopy. Products included methane, ketene, 1‐propen‐2‐ol (the enol isomer of acetone), CO, HCO, ethane, ethane, acetylene and CCCO. Product absolute and relative yields varied with acetone number density, the choice of anode geometry and the rate of electron bombardment. The overall chemistry observed is rationalized in terms of mechanistic steps involving unimolecular cation decomposition, ion–molecule reactions, radical–radical reactions and dissociative recombination processes. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
27.
Chadi Khoury François Le Goffic Marie‐Noëlle Rager 《Journal of carbohydrate chemistry》2013,32(7):395-409
The synthesis of 2‐acetamido‐2‐deoxy‐6‐O‐octanoyl‐D‐glucono‐1,5‐lactone 9 and 2‐acetamido‐2‐deoxy‐6‐O‐octanoyl‐α‐D‐glucopyranose 7 from 2‐acetamido‐2‐deoxy‐α‐D‐glucopyranose is reported. For both targets, the key intermediate was allyl 2‐acetamido‐3,4‐di‐O‐benzyl‐2‐deoxy‐6‐O‐octanoyl‐α‐D‐glucopyranoside 5. Surface tension measurements (critical micellar concentration of 22.3 mM and 5 mM for 9 and 7, respectively) showed up the surface activity of both compounds, while enzyme inhibition assays indicated that 9 could inhibit bovine β‐N‐acetylglucosaminidase (Ki=6.5 µM) but not Serratia marcescens chitobiase nor hen egg‐white lysozyme. Moreover, 7 was shown to induce chitinase production of S. marcescens and to be readily metabolized by these bacteria. 相似文献
28.
采用后合成法制备MnOx/Al-SBA-15催化剂, 考察了催化剂的低温NH3选择性催化还原(SCR)NOx的性能. 利用傅里叶透射红外变换(FTIR)光谱、N2吸附-脱附、X射线衍射(XRD)、扫描电镜(SEM)、拉曼光谱(Raman)、X射线光电子能谱(XPS)及NH3程序升温脱附(NH3-TPD)的表征手段, 对催化剂的结构性质和SCR性能进行了系统分析. 结果表明, 适量Al的掺杂能提高MnOx/SBA-15催化剂的SCR活性, 当硅铝摩尔比为50时, 催化剂活性最佳. 表征结果显示, Al掺杂后, 催化剂仍保持良好的骨架结构, 较大比表面、孔容和孔径, 并且Mn在催化剂表面富集, 由低价态转化为高价态, MnO2为催化剂的主要活性相. 此外, Al的掺杂使MnOx在催化剂表面高度分散, 表面酸性增强, 从而提高了催化剂的SCR活性. 相似文献
29.
钟彬扬 《广东微量元素科学》2014,(9):12-15
目的为了快速准确的测定高校室内空气中甲醛浓度。方法采用乙酰丙酮分光光度法,对计算机房、物理实验室、化学实验室三个房间的甲醛浓度进行了测定分析。结果相对于化学实验室来说,计算机房的甲醛浓度多了0.77倍;物理实验室的甲醛浓度比化学实验室的多了0.98倍。结论室内空气质量可能会受新房对甲醛的释放时间以及室内新家具的存放时间影响;乙酰丙酮分光光度法具有简便、易控制、成本低等优点,可以广泛使用于普通室内甲醛浓度的测定。 相似文献
30.