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Jiamin Sun Dr. Himanshu Sekhar Jena Dr. Chidharth Krishnaraj Dr. Kuber Singh Rawat Dr. Sara Abednatanzi Dr. Jeet Chakraborty Andreas Laemont Wanlu Liu Hui Chen Prof. Ying-Ya Liu Dr. Karen Leus Prof. Henk Vrielinck Prof. Veronique Van Speybroeck Prof. Pascal Van Der Voort 《Angewandte Chemie (International ed. in English)》2023,62(19):e202216719
Four highly porous covalent organic frameworks (COFs) containing pyrene units were prepared and explored for photocatalytic H2O2 production. The experimental studies are complemented by density functional theory calculations, proving that the pyrene unit is more active for H2O2 production than the bipyridine and (diarylamino)benzene units reported previously. H2O2 decomposition experiments verified that the distribution of pyrene units over a large surface area of COFs plays an important role in catalytic performance. The Py-Py-COF though contains more pyrene units than other COFs which induces a high H2O2 decomposition due to a dense concentration of pyrene in close proximity over a limited surface area. Therefore, a two-phase reaction system (water-benzyl alcohol) was employed to inhibit H2O2 decomposition. This is the first report on applying pyrene-based COFs in a two-phase system for photocatalytic H2O2 generation. 相似文献
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Shukla Pushpendra Kumar Misra Ankita Kumar Manish Rajan Soundararajan Agrawal Pawan Kumar Rawat Ajay Kumar Singh Srivastava Sharad 《平面色谱法杂志一现代薄层色谱法》2016,29(5):347-355
JPC – Journal of Planar Chromatography – Modern TLC - Plant metabolite varies with season and geographic conditions. The present study is aimed at the identification of the potential... 相似文献
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ZrSiN thin films are synthesized by using plasma focus through various numbers of focus shots (10, 20, and 30), with samples placed at 9 cm away from the tip of the anode. Crystal structures, surface morphologies, and elemental compositions of ZrSiN films are characterized by an X-ray diffractometer (XRD) and scanning electron microscope (SEM) attached with energy dispersive X-ray spectroscopy (EDS). XRD patterns confirm the formations of polycrystalline ZrSiN films. Crystallinity of nitride increases with the increase of focus shot number. The average crystallite size of zirconium nitride increases from 27 ± 3 nm to 73±8 nm and microstrain decreases from 2.28 to 1.0 with the increase of the focus shot number. SEM results exhibit the formations of granular and oval-shaped microstructures, depending on the number of focus shots. EDS results confirm the presences of silicon, zirconium, nitrogen, and oxygen in the composite films. The content values of Zr and N in the composite films increase with the increase of the focus shot number. 相似文献
127.
Structural Chemistry - This study focuses on the biological prospects of oxygen-depleted calix[4]arene ligands on a protein target. Because of their extensive medical relevance, the oxygen-depleted... 相似文献
128.
Maurya Rajiv K. Sharma Priyamedha Rawat Rajeev Singh Ravi S. R. Bindu 《The European Physical Journal B - Condensed Matter and Complex Systems》2019,92(8):1-5
The European Physical Journal B - It has experimentally been found by Lampo et al. [Biophys. J. 112, 532 (2017)] that, for two different types of cell, the distribution of the diffusivities of... 相似文献
129.
Polyaniline coated on particles of celite is used as support to load palladium catalyst. This heterogenized Celite?PANI?Pd system, is used as an efficient catalyst for chemoselective hydrogenation reactions. The catalyst is characterized by usual spectral, analytical techniques and studied for hydrogenation reactions at ambient conditions. The mild reaction conditions allow the control over the reactions and excellent selectivity is achieved in number of conversions. Hydrogenation of a carbon–carbon double bond was favored over other polar π‐bond systems, while labile functional groups such as benzyl ether, benzyl esters, cyano, nitro and halogen remained unaffected. Primary amines were converted to N,N‐dimethyl amines with formaldehyde, the double bond of coumarin was selectively hydrogenated without opening of the lactone functionality. 相似文献
130.
A rapid LC-photodiode array method for the separation and identification of secondary plant metabolites especially phenolic compounds belonging to different types in a run (35 min) has been developed. The method has been optimized and validated using the selectivity, precision, recovery and robustness parameters with an aim for standardization of herbal drugs. Almost all the compounds have linearity with an R 2 more than 98% and an RSD of less than 5% (in terms of variation of retention time). Inter-day and intra-day variability was also found to be less than 5%. The method thus developed has been successfully applied in identification and quantification of phenolic compounds present in polyherbal ayurvedic formulation (Ashokarishta). The results indicate that the method developed is rapid, accurate and robust for the analysis of different classes of phenolic compounds and can be successfully applied in the quality control and standardization of herbal drugs as well as polyherbal formulations. 相似文献