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101.
Bhawna Kaushik Pooja Rana Deepti Rawat Kanika Solanki Pooja Rana Shallu Sachdeva Dhanaji R. Naikwadi Ankush V. Biradar Rakesh K. Sharma 《应用有机金属化学》2023,37(1):e6936
Construction of an effective heterojunction for unimpeded flow of photogenerated charges and their prolonged separation is imperative for environmental photocatalysis. Herein, we have designed an efficient magnetic ZnO/BiVO4 type-II heterostructure, which was employed for proficient degradation of persistent methyl violet dye with an efficiency of 97.6% in 90 min and a hazardous organic pollutant, namely, bisphenol A. UV-DRS and photoluminescence studies demonstrated that the fabricated nanocomposite exhibited effective light absorption and prolonged charge separation, thereby resulting in high photocatalytic efficacy under visible light irradiation. The efficacy of developed magnetic ZnO/BiVO4 was also compared with pristine BiVO4 and undoped magnetic ZnO, which indicated that the constructed heterostructure displayed approximately threefold and sixfold activity in contrast with bare BiVO4 and undoped magnetic ZnO nanoparticles, respectively. Radical trapping studies, ESR analysis along with GC-MS analysis were conducted to elucidate the mechanistic pathway during the photodegradation process. This work provides a rational technical approach and research ideas for photocatalytic degradation of harmful organic pollutants in an environment-friendly manner by employing energy-efficient LEDs. Besides, good recyclability of catalyst makes it a promising candidate for large-scale applications. 相似文献
102.
The toxicological effects, biological aspects and spectral characterization of organoboron(III) complexes of sulfonamide‐imines derived by the condensation of salicylaldehyde with different sulfa‐drugs are described. The benzene‐soluble, high‐molecular‐weight complexes have been characterized using a wide range of analytical and spectroscopic techniques, viz. UV, IR, 1H and 11B NMR. On the basis of these studies, it is inferred that the imines derived from sulfa drugs and salicylaldehyde behave as dibasic tridentate ligands and thus provide a tetrahedral environment around the boron atom. Finally, all these complexes have been screened for their antimicrobial activity against a variety of fungal and bacterial strains and their toxicological effects on male albino rats examined at the dosages employed. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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104.
Jagjeet Kaur Deepti Singh Vikas Dubey N. S. Suryanarayana Yogita Parganiha Pooja Jha 《Research on Chemical Intermediates》2014,40(8):2737-2771
In this review different methods of preparing lanthanum aluminate (LaAlO3) phosphors are discussed. The molten salt method, the combustion method, the sucrose method, and the coprecipitation technique are the best methods for preparing LaAlO3 phosphors with small particle size and high surface area by low-temperature synthesis. LaAlO3 usually has a rhombohedral structure. It has good dielectric properties and, hence, is regarded as an attractive alternative to SiO2 in microelectronic devices. LaAlO3 phosphors have excellent chemical and thermal stability, mechanical durability, and exploitable optical and electronic properties, leading to a wide range of potential applications. LaAlO3 phosphors doped with rare-earth ions have luminescence properties and can, hence, be used in optical display systems. 相似文献
105.
Silymarin,a polyphenolic flavonoid impede Plasmodium falciparum growth through interaction with heme
Pooja Rani Mina Yogesh Kumar Ajeet Kumar Verma Feroz Khan Sudeep Tandon Anirban Pal 《Natural product research》2020,34(18):2647-2651
AbstractA polyphenolic flavonoid, Silymarin isolated from Silybum marianum is widely known for its hepatoprotective action. In the present study anti-plasmodial activity of Silymarin has been demonstrated for the first time having IC50 of 14?±?0.33?μM against the NF-54 strain of P. falciparum with high selectivity index (>100). The parasitostatic action is exerted through inhibition of β-hematin/hemozoin formation which is due to the interaction (Kd?=?3.63?±?0.9µM) of silymarin with free heme in a Stoichiometry of 1:1 Silymarin: heme complex resulting into heme-induced membrane damage in the parasite. Silymarin could hinder the glutathione and hydrogen peroxide-induced heme detoxification. Silymarin also induces apoptosis in the parasite through the elevation of caspase-3 level in a dose-dependent manner. Results from the docking studies suggest that Silymarin interacts with heme. 相似文献
106.
Basak A Bag SS Majumder PA Das AK Bertolasi V 《The Journal of organic chemistry》2004,69(20):6927-6930
The synthesis and chemical reactivity of pyridazinedione-based enediynes (1, 2) are described. Both of these enediynes, namely the dihydro compound 1 and its corresponding tetrahydro analogue 2, were prepared by double N,O-alkylation of the corresponding heterocyclic system with the acyclic enediynyl dibromide 8 in good yields. Their single-crystal X-ray structures revealed similar c, d distances (distance between the acetylenic carbons undergoing covalent connection in Bergman cyclization). Interestingly, these molecules undergo Bergman cyclization at different rates, and the reactivity is shown to be dependent upon the state of hybridization of C-4 and C-5 atoms of the parent heterocyclic ring. 相似文献
107.
108.
Bharati Devesh Chandra Rawat Pooja Saroj A. L. 《Journal of Solid State Electrochemistry》2021,25(6):1727-1741
Journal of Solid State Electrochemistry - A series of biopolymer blend electrolytes (BPBEs) based on ((100-x)PVA-xCS)-NaI, viz. BPBE-1 to BPBE-5 (x = 10, 20, 30, 40, 50 in wt%), respectively, were... 相似文献
109.
110.
Multiple exciton recombination (MER) and multiple exciton generation (MEG) are two of the main processes for assessing the usefulness of quantum dots (QDs) in photovoltaic devices. Recent experiments, however, have shown that a firm understanding of both processes is far from well established. By performing surface-dependent measurements on colloidal CdSe QDs, we find that surface-induced charge trapping processes lead to false MER and MEG signals resulting in an inaccurate measurement of these processes. Our results show that surface-induced processes create a significant contribution to the observed discrepancies in both MER and MEG experiments. Spectral signatures in the transient absorption signals reveal the physical origin of these false signals. 相似文献