排序方式: 共有49条查询结果,搜索用时 281 毫秒
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二次加工柴油中烯烃的分析 总被引:1,自引:0,他引:1
采用溴价电子轰击质谱、核磁共报氢谱以及溴加成/场电离质谱等综合分析二次加工柴油中的燃烃。 相似文献
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Wang Cheng Li Jianqiao Zhang Zelong Ye Lei Xia Weiluo Xia Weidong 《Plasma Chemistry and Plasma Processing》2019,39(1):259-276
Plasma Chemistry and Plasma Processing - Cathode spots present complex forms in magnetically rotating arc plasma generators due to the coupling effect of the plasma flow and electromagnetic fields.... 相似文献
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采用超高效合相色谱法(UPC2)拆分三唑酮、三唑醇、己唑醇、戊唑醇、联苯三唑醇、腈菌唑等6种三唑类农药对映体,并测定了黄瓜中6种三唑类农药对映体的残留量。样品经乙腈均质提取,石墨化炭黑(GCB)、自制弗罗里硅土柱和QuEChERS试剂依次净化后,Acquity Trefoil AMY1手性色谱柱分离,以超临界二氧化碳-甲醇等助溶剂为流动相进行梯度洗脱,外标法定量。方法定量限(S/N>10)均为0.1 mg/kg,在黄瓜中分别添加0.1、0.2、0.5 mg/kg 3个水平的三唑类农药对映体,其回收率为65.1%~116%,相对标准偏差(n=6)为1.0%~9.6%。该方法实现了对6种三唑类农药16种对映体的拆分及其在黄瓜基质中的残留测定,可为手性农药开发、使用及相关法规的制定提供科学支撑。 相似文献
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采用十六烷基三甲基溴化铵(CTAB)和六亚甲基亚胺(HMI)组成双模板体系,以气相二氧化硅为硅源,在150 ℃下动态原位合成了薄层的MWW型MCM-22分子筛纳米片,并考察了CTAB添加量对分子筛产物的影响。采用粉末X射线衍射(PXRD)、扫描电子显微镜(SEM)、N2吸附-脱附、氨气程序升温脱附(NH3-TPD)、高倍透射电子显微镜(HRTEM)、吡啶红外(Py-IR)和2,6-二叔丁基吡啶红外(DTBPy-IR)测试方法对合成的分子筛样品进行表征。结果表明:采用双模板体系可以制备出5~10 nm的薄层MWW型纳米片。同时,通过偏三甲苯异构化反应对样品的催化性能进行了表征,催化结果显示样品d-MWW-4%CTAB具有较好的催化性能,其中偏三甲苯的质量转化率、均三甲苯质量收率及均三甲苯选择性分别为34.97%、22.42%和64.09%,这主要归因于薄层纳米片MCM-22具有的较大外表面积和片层间形成的晶间介孔结构。 相似文献
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CHEN Bingda ZHANG Zelong SU Meng QIN Feifei PAN Qi XIE Daixi YANG Xu ZHANG Kun ZHANG Zeying XIE Hongfei CARMELIET Jan SONG Yanlin 《高等学校化学研究》2023,39(1):133-138
Traditional synthesis strategy of nanomaterials with complicated process and high cost limits their applications. Here, we propose a facile process for the synchronous synthesis and patterning of silver nanoparticles(Ag NPs) through the self-driven microchannel reactor with the capillary effect inspired by transpiration. The evaporation contributes to capillary and accumulation effects in the microchannels. The silver reactant-containing droplets can be spontaneously divided and distributed in multiple microchannels during the whole fabrication process by the capillary effect. The newly formed Ag NPs at the gas-liquid interface can be assembled on both sides of the microchannels by the accumulation effect. The capillary effect decreases the disturbances, which ensures the uniformity of the patterning. By the combination of microchannels with different widths, various Ag NPs-assembled patterns with stable electrical properties are achieved. This efficient strategy with a simple fabrication procedure is towards the technological engineering of nanoscale architected materials. 相似文献
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Panpan Sun Zelong Qiao Prof. Shitao Wang Danyang Li Xuerui Liu Prof. Qinghua Zhang Prof. Lirong Zheng Prof. Zhongbin Zhuang Prof. Dapeng Cao 《Angewandte Chemie (International ed. in English)》2023,62(6):e202216041
To achieve practical application of fuel cell, it is vital to develop highly efficient and durable Pt-free catalysts. Herein, we prepare atomically dispersed ZnNC catalysts with Zn-Pyrrolic-N4 moieties and abundant mesoporous structure. The ZnNC-based anion-exchange membrane fuel cell (AEMFC) presents an ultrahigh peak power density of 1.63 and 0.83 W cm−2 in H2-O2 and H2-air (CO2-free), and also exhibits long-term stability with more than 120 and 100 h for H2-air (CO2-free) and H2-O2, respectively. Density functional calculations further unveil that the Zn-Pyrrolic-N4 structure is the origin of high activity of as-synthesized ZnNC catalyst, while the Zn-Pyridinic-N4 moiety is inactive for oxygen reduction reaction (ORR), which successfully explain the puzzle why most Zn-metal-organic framework -derived ZnNC catalysts in previous reports did not present good ORR activity because of their Zn-Pyridinic-N4 moieties. This work offers a new route for speeding up development of AEMFCs. 相似文献