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排序方式: 共有242条查询结果,搜索用时 31 毫秒
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Singh Swati Bawitlung Laldingngheti Singh Munmun Kumar Chauhan Amit Padalia Rajendra Chandra Pal Anirban Verma Ram Swaroop 《Chemistry of Natural Compounds》2022,58(1):161-162
Chemistry of Natural Compounds - 相似文献
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The conventional condensation and refluxing process was employed to synthesize Ni(II) and Cu(II) complexes of Methylcarbamatethiosemicarbazone ligand. Reactions were carried out at the pH of 7. The molar ratio of the ligand and metal salt was 2:1. The structures of the synthesized metal complexes were suggested by different analytical techniques such as magnetic susceptibility, molar conductance, IR, EPR and UV spectroscopy. Experimental studies confirmed the octahedral geometry for all the complexes. The geometry of the ligand and complexes were also confirmed by theoretical studies. The complexes were investigated for biological action against pathogenic fungi (C. krusei, C. albican) and bacteria (S. aureus, E. coli). The antimicrobial results confirmed superior inhibition potential of the metal complexes as compared with the parent ligand. The enhanced antimicrobial activities might be due to the chelation. Molecular-docking assays confirmed the strong interaction of ligand with target antimicrobial protein DNA gyrase-B. 相似文献
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Dr. Swati Deswal Rishukumar Panday Dr. Dipti R. Naphade Prashant Dixit Dr. Balu Praveenkumar Dr. Jan K. Zaręba Prof. Dr. Thomas D. Anthopoulos Prof. Dr. Satishchandra Ogale Prof. Dr. Ramamoorthy Boomishankar 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(33):e202200751
Bismuth containing hybrid molecular ferroelectrics are receiving tremendous attention in recent years owing to their stable and non-toxic composition. However, these perovskite-like structures are primarily limited to ammonium cations. Herein, we report a new phosphonium based discrete perovskite-like hybrid ferroelectric with a formula [Me(Ph)3P]3[Bi2Br9] ( MTPBB ) and its mechanical energy harvesting capability. The Polarization-Electric field (P-E) measurements resulted in a well-defined ferroelectric hysteresis loop with a remnant polarization value of 2.1 μC cm−2. Piezoresponse force microscopy experiments enabled visualization of the ferroelectric domain structure and evaluation of the piezoelectric strain coefficient (d33) for an MTPBB single crystal and thin film sample. Furthermore, flexible devices incorporating MTPBB in polydimethylsiloxane (PDMS) matrix at various concentrations were fabricated and explored for their mechanical energy harvesting properties. The champion device with 20 wt % of MTPBB in PDMS rendered a maximum peak-to-peak open-circuit voltage of 22.9 V and a maximum power density of 7 μW cm−2 at an optimal load of 4 MΩ. Moreover, the potential of MTPBB -based devices in low power electronics was demonstrated by storing the harvested energy in various electrolytic capacitors. 相似文献
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Vinod Bhatt Nitisha Sendri Km Swati Shinde Bhagatsing Devidas Pamita Bhandari 《Journal of separation science》2022,45(14):2555-2565
The current study aimed to investigate the anthocyanins, non-anthocyanins (flavonoids and phenolic acids), and free radicals scavenging potential in the flowers of Rhododendron arboreum using ultra high performance liquid chromatography with ion mobility quadrupole time of flight tandem mass spectrometry. A total of 25 constituents including nine anthocyanins, six phenolic acids, and ten flavonoids were identified in the flower extract. The major anthocyanins identified were cyanidin-3-O-β-galactoside ( 1 ), cyanidin-3-O-α-arabinoside ( 4 ), and cyanidin-3-O-rhamnoside ( 8 ), while quercetin glycosides were the main identified flavonoids in R. arboreum flowers. Additionally, ultra high performance liquid chromatography methods were developed and validated for the quantification of nine compounds (anthocyanins, flavonoid glycosides, and phenolic acids); five of them were quantified using internal standards. The extracts were analyzed for total phenolics (123.6 mg GAE/g), anthocyanin content (1.76% w/w), and evaluated for antioxidant properties against 2,2-diphenyl-1-picrylhydrazyl radical (IC50: 102.06 and 96.92 μg/mL) and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) radical cation (112.25 and 45.59 μM TE/g) assays. The profiling of R. arboreum for anthocyanins is reported for the first time. The findings suggest that the flowers are a promising source of bioactive constituents and could be used as functional food, antioxidants, and nutraceuticals. 相似文献
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Swati?Tyagi Syed?AbbasEmail author Manuel?Pinto Daniel?Sepúlveda 《Mediterranean Journal of Mathematics》2017,14(1):23
In this paper, we study a class of fractional-order cellular neural network containing delay. We prove the existence and uniqueness of the equilibrium solution followed by boundedness. Based on the theory of fractional calculus, we approximate the solution of the corresponding neural network model over the interval \([0,\infty )\) using discretization method with piecewise constant arguments and variation of constants formula for fractional differential equations. Furthermore, we conclude that the solution of the fractional-delayed system can be approximated for large t by the solution of the equation with piecewise constant arguments, if the corresponding linear system is exponentially stable. At the end, we give two numerical examples to validate our theoretical findings. 相似文献
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Curcumin (Cur), a natural colorant found in the roots of the Turmeric plant, has been reported for the first time as photoinitiator for the copolymerization of styrene (Sty) and methylmethacrylate (MMA). The kinetic data, inhibiting effect of benzoquinone and ESR studies indicate that the polymerization proceeds via a free radical mechanism. The system follows ideal kinetics (Rp α[Cur]0.5[Sty]0.97[MMA]1). The reactivity ratios calculated by using the Finemann–Ross and Kelen‐Tudos models were r1(MMA)=0.46 and r2(Sty)=0.52. IR and NMR analysis confirmed the structure of the copolymer. NMR spectrum showing methoxy protons as three distinct groups of resonance between 2.2–3.75 δ and phenyl protons of styrene at 6.8–7.1 δ confirmed the random nature of the copolymer. The mechanism for formation of radicals and random copolymer of styrene and MMA [Sty‐co‐MMA] is also discussed. 相似文献
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Priyabrata Das Suvra Mandal Sudeshna Gangopadhyay Kalipada Das Arpita Ghosh Mitra Swati Dasgupta 《Natural product research》2016,30(4):474-477
Methylphophorbide a (MPa) has been isolated from the ethanol extract of the wheat grass plant. Its antioxidative efficacy is evaluated by hydroxyl radical scavenging activities and reducing capacity which are significantly up regulated in comparison with aqueous extract of the plant. The compound shows iron-binding capacity where the Fe2+ binds with MPa by two types of binding patterns with dissociation constants 157.17 and 27.89. It has antioxidative and cytotoxic effects on HeLa and Hep G2 cells. The cancerous cell survivability decreases with increasing concentration of MPa. These findings have provided evidence for the traditional use of the wheat grass plant in the treatment of cancers, oxidative stress and iron overloaded disorders. 相似文献
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