排序方式: 共有63条查询结果,搜索用时 15 毫秒
31.
Elumalai Kowsalya Kithiyon MosaChristas Chinna Rani Inbaraj Jaquline Pannerselvam Balashanmugam Thiyagarajan Devasena 《应用有机金属化学》2021,35(1)
Green synthesis of functionalized gold nanoparticles has been considered to be more biocompatible and has gained much attention in recent years. The eco‐friendly synthesis, long half‐life of drugs, low cost, and nontoxicity make them an appealing potential option for the biomedical field. The leaf aqueous extract of 10 different plants, namely, Araucaria heterophylla (Ah), Lagerstroemia indica (Li), Combretum indicum (Ci), Melia azedarach (Ma), Muntingia calabura (Mc), Hygrophila auriculata (Ha), Rivina humilis (Rh), Callistemon lanceolatus (Cl), Pterygota alata (Pa), and Vateria indica (Vi) was used for the synthesis of gold nanoparticles (AuNPs). Among them, six plants supported the synthesis of stable AuNPs. The generation of ruby red from pale yellow color proved AuNPs synthesis and which was further confirmed by the absorption peak in UV–Vis spectroscopy. Enhanced antioxidant activity was found with Pa–AuNPs compared with other phytosynthesized AuNPs. Pa–AuNPs were thus characterized by HR‐TEM, EDX, XRD, and FTIR. Pa–AuNPs exhibited potent dose‐dependent anticancer efficacy and an effective dose of IC50 mediated apoptosis and necrosis in MCF‐7 breast cancer cells. Pa–AuNPs significantly enhanced the generation of ROS, in effect inducing mitochondrial membrane sensitization to trigger the cascade of apoptosis. The research highlights the effectiveness of AuNPs on cancer cells in vitro and, in turn, a progressive step toward novel biomedical applications. These findings indicate that phytosynthesized AuNPs may be an enticing anti‐cancer strategy for breast cancer without eliciting toxicity to normal cells. 相似文献
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B. Muthuraaman Thiyagarajan Shanmugam P. Maruthamuthu A. Sultan Nasar 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(9):965-970
Hyperbranched poly(aryl-ether-urethane) is reported in this work as an efficient polymer electrolyte for photovoltaic application. Along with KI and I2 as redox carriers in nanocrystalline dye-sensitized solar cell (DSC), this polymer yielded an overall conversion efficiency of 4.1%, upon illumination with visible light. The fabricated cell results in stable device performing under thermal stress maintaining about 70% of its initial value for 2 days in the direct atmosphere without sealing. 相似文献
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Subbiah A Pyle D Rowland A Huang J Narayanan RA Thiyagarajan P Zoń J Clearfield A 《Journal of the American Chemical Society》2005,127(31):10826-10827
Reaction of Sn(IV) with phosphonic acids results in the formation of tin phosphonates with a spherical morphology arising from the aggregation of nanosized individual particles. Under high magnification, the spheres are shown to be porous with surface areas of 200-515 m2/g, depending on the type of phosphonic acid and the synthesis conditions used. The pores are largely micro in nature but also somewhat dependent on the type of phosphonic acid utilized in the preparation. Both aliphatic and aromatic organic phosphonates form these spherical aggregates. Functional groups, such as amino and carboxyl, may be introduced as part of the phosphonic acid or subsequently by further reaction, leading to a large family of naturally formed nanoparticles with accompanying microporosity. 相似文献
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Narayanan RA Thiyagarajan P Lewis S Bansal A Schadler LS Lurio LB 《Physical review letters》2006,97(7):075505
A small amount of alumina nanoparticles in polymethylmethacrylate causes a sharp depression of the glass transition temperature (Tg) accompanied by a toughening of the composite. We investigated this phenomenon using multispeckle x-ray photon correlation spectroscopy. Measurements reveal a dynamic structure factor that has the form exp[-(t/taua)beta], with beta greater than 1. We show for the first time that beta(T) tracks the internal stress at the polymer-particle interface. The internal stress, which we propose arises due to the entropic penalty that the polymer faces in the presence of the nanoparticles, engenders temporally heterogeneous dynamics. In the jammed glassy state, we show that the dominant fast relaxation mode--taumax--aided by a weak dewetting interface relieves the stress and follows the variations in Tg. 相似文献
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Helical conformational specificity of enzymatically synthesized water-soluble conducting polyaniline nanocomposites 总被引:5,自引:0,他引:5
Thiyagarajan M Samuelson LA Kumar J Cholli AL 《Journal of the American Chemical Society》2003,125(38):11502-11503
A novel template guided enzymatic approach has been developed to synthesize optically active conducting polyaniline (PANI) nanocomposites in the presence of H2O2 as an oxidant, using (+) and (-) 10-camphorsulfonic acid (CSA) as a dopant and chiral inductor. The formation of chiral polyaniline in the nanocomposites was confirmed by circular dichroism (CD). Interestingly, the CD spectra of nanocomposites formed either with (+) or with (-) CSA show the enzyme itself plays a critical role in controlling the stereospecificity of the polyaniline (PANI) in the nanocomposite. The enzyme used for the polymerization of aniline in the nanocomposite was horseradish peroxidase (HRP). It was shown that this enzyme prefers a specific helical conformation, regardless of whether induced chirality in the complex CSA-aniline is from (+) or (-) CSA. UV-vis spectra show that the polyaniline is in the conducting form, and transmission electron micrographs (TEM) show that the nanocomposites are dispersed nicely with particle size dimensions in the range of 20-50 nm. Electron diffraction patterns of these chiral polymer nanocomposites suggest that these nanocomposites are in both crystalline and amorphous states. 相似文献
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Panchatcharam Thiyagarajan M. S. Ramachandra Rao 《Applied Physics A: Materials Science & Processing》2010,99(4):947-953
Rare earth ions (Ce3+, Eu2+) activated Ca3MgSi2O8 (CMSO) phosphors have been synthesized using solid-state reaction method in 95%N2+5%H2 reduction atmosphere at elevated temperatures by varying Eu2+ concentration from 0.0075 to 0.0300 at the fixed Ce0.03 concentration to study their photoluminescence (PL) properties. An energy transfer occurs from Ce3+ to Eu2+ through a significant overlap of Eu2+ excitation spectrum with Ce3+ emission spectrum in CMSO, together with the systematic relative decrease and increase in emission bands of Ce3+ and Eu2+, respectively, have been observed. To support the phenomenon, diffuse reflectance spectra show various absorption levels corresponding to Ce3+, Eu2+, and/or mixture of both rare earth ions. An optimum emission was realized at 0.0150 of Eu2+ via. energy transfer from Ce3+ ion. By utilizing the principle of energy transfer, the critical distance (R c ) between activator ions was found to be 18.64 Å. The CIE chromaticity coordinates measured on the Ca3MgSi2O8:Ce3+, Eu2+ phosphors excited under ultraviolet (365 nm) source shows the values lie in cool white light region could be applied to solid state lighting. 相似文献
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Barun K. Datta Durairaj Thiyagarajan Chirantan Kar Aiyagari Ramesh Gopal Das 《Analytica chimica acta》2015
A new tricarbocyanine-based chemosensor exhibited a dramatic Al3+-specific fluorescence turn-on response in the near-infrared (NIR) region. The receptor was found to be highly selective towards Al3+ over other metal ions in physiological condition. The sensor was non-toxic and could thus be employed as an imaging probe for detecting intracellular Al3+ in live cells. Interestingly, upon interaction with DNA in solution, the L–Al3+ ensemble rendered tracking of DNase activity in solution through a systematic reduction in the fluorescence emission intensity. 相似文献
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Siluvaimuthu S. Thiyagarajan S. Martin Leenus Jesu Nagalingam B. 《Journal of Thermal Analysis and Calorimetry》2020,140(4):1945-1956
Journal of Thermal Analysis and Calorimetry - High-viscous neat neem oil (NO) with low-viscous wintergreen oil (WGO) may be used in diesel engines without any engine modification. Based on the... 相似文献