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排序方式: 共有711条查询结果,搜索用时 31 毫秒
1.
Tamil Selvi Gopal Soon Kwan Jeong Tahani A. Alrebdi Saravanan Pandiaraj Abdullah Alodhayb Muthumareeswaran Muthuramamoorthy 《Materials Today Chemistry》2022
A recently discovered 2D transition titanium metal carbides also called as MXenes (Ti3C2Tx)-based nanocomposite was prepared with Cu2O through wet precipitation technique, and these materials were further developed as the electrode for sensing glucose by chronoamperometry technique. The prepared MXene-Cu2O (Ti3C2Tx-Cu2O) nanocomposite was characterized by XRD, FTIR, UV–Vis spectroscopy, FE-SEM, EDAX, and Raman spectroscopy. Morphological studies of the composites revealed that the micro-octahedral shape of Cu2O is distributed on the surface of MXene with size larger than bare Cu2O. Further, the prepared composite material was fabricated as a sensing probe, and the electrochemical activities were examined by cyclic voltammetric analysis (CV) and chronoamperometric (CA) methods. From the CV and CA investigation, the current response was higher for the composite than the bare material (Cu2O & MXene) in the presence of glucose. The amperometric investigation of MXene-Cu2O composite for the detection of glucose shows a broad linear range (0.01–30 mM) with a sensitivity of 11.061/μAmM cm?2 and a detection limit of 2.83 μM. Further, the fabricated sensor exhibits good selectivity with interfering species like NaCl, fructose, sucrose, urea, ascorbic acid, lactose, short response time, stability, good reproducibility, and compatibility with human serum sample. From the investigation, the prepared MXene-Cu2O composite is a good candidate for the direct detection of glucose molecules and is also well suitable for clinical diagnosis. 相似文献
2.
Gopal Krishan M. S. Rao C. P. Kumar Prabhat Semwal 《Journal of Radioanalytical and Nuclear Chemistry》2015,303(3):2221-2225
3.
Prof. Dr. Jean Christophe Tremblay Ambre Blanc Dr. Pascal Krause Sucharita Giri Prof. Gopal Dixit 《Chemphyschem》2023,24(2):e202200463
The present work focuses on probing ultrafast charge migration after symmetry-breaking excitation using ultrashort laser pulses. LiCN is chosen as prototypical system because it can be oriented in the laboratory frame and it possesses optically-accessible charge transfer states at low energies. The charge migration is simulated within the hybrid time-dependent density functional theory/configuration interaction framework. Time-resolved electronic current densities and simulated time-resolved x-ray diffraction signals are used to unravel the mechanism of charge migration. Our simulations demonstrate that specific choices of laser polarization lead to a control over the symmetry of the induced charge migration. Moreover, time-resolved x-ray diffraction signals are shown to encode transient symmetry reduction at intermediate times. 相似文献
4.
Shiran Aharon Dr. Shanti Gopal Patra Prof. Dr. Dan Meyerstein Dr. Eyal Tzur Dr. Dror Shamir Dr. Yael Albo Prof. Dr. Ariela Burg 《Chemphyschem》2023,24(22):e202300517
The Na3[Ru2(μ-CO3)4] complex is acting as a water oxidation catalyst in a homogeneous system. Due to the significance of heterogeneous systems and the effect of bicarbonate on the kinetic, we studied the bicarbonate effect on the heterogeneous electrocatalyst by entrapping the Na3[Ru2(μ-CO3)4] complex in a sol-gel matrix. We have developed two types of sol-gel electrodes, which differ by the precursor, and are demonstrating their stability over a minimum of 200 electrochemical cycles. The pH increases affected the currents and kcat for both types of electrodes, and their hydrophobicity, which was obtained from the precursor type, influenced the electrocatalytic process rate. The results indicate that NaHCO3 has an important role in the catalytic activity of the presented heterogeneous systems; without NaHCO3, the diffusing species is probably OH−, which undergoes diffusion via the Grotthuss mechanism. To the best of our knowledge, this is the first study to present a simple and fast one-step entrapment process for the Na3[Ru2(μ-CO3)4] complex by the sol-gel method under standard laboratory conditions. The results contribute to optimizing the WSP, ultimately helping expand the usage of hydrogen as a green and more readily available energy source. 相似文献
5.
Gopal Senthil Kumar Matthias Zeller Michael A. Frasso Karnam Jayarampillai Rajendra Prasad 《Journal of heterocyclic chemistry》2015,52(3):926-930
An efficient and economical method has been developed for the synthesis of pyrano[3,2‐h]quinolines via an indium trichloride‐catalyzed one‐pot three‐component reaction of 8‐hydroxyquinoline with aromatic aldehydes and malononitrile/ethyl cyanoacetate under microwave irradiation. 相似文献
6.
Lakshmi Kasirajan Kalaivaani Aruchamy Prathima P. Thirugnanasambandam Selvi Athiappan 《Applied biochemistry and biotechnology》2017,181(4):1270-1282
Sugarcane (Saccharum spp.) is one of the highest biomass-producing plant and the best lignocellulosic feedstock for ethanol production. To achieve more efficient conversion of biomass to ethanol, a better understanding of the main factors affecting biomass recalcitrance is needed. Therefore, with this objective, here, we report a systematic study on lignin content, deposition, identification, and cloning of genes involved in lignin biosynthesis and their differential expression in five sugarcane clones, EC11003, EC11010, IK 76-91, IK 76-99, and Co 86032. Lignin content among the clones varied from 26.87 to 23.19 % with the highest in the clone EC11010 and the lowest in high sugar Co86032. Lignin deposition studied through phloroglucinol staining of the cell walls implied that the sclerenchyma cells of the energy canes (EC11010 and EC11003) have more lignin deposition followed by the Erianthus (IK 76-91 and IK 76-99) clones whereas Co86032 has the minimum amount of lignin deposition. We cloned partial coding regions of important genes of lignification COMT (650 bp), CCR (332 bp), and PAL (650 bp) from Erianthus, wild relative of sugarcane followed by the expression analysis through real-time PCR. Differential expression analysis showed high level of expression for the three genes in the energy cane EC11010. 相似文献
7.
Ramdas S. Pathare Shivani Sharma Kandasamy Gopal Devesh M. Sawant Ram T. Pardasani 《Tetrahedron letters》2017,58(14):1387-1389
An efficient one-pot protocol for the synthesis of multi-substituted 2-pyrone derivatives from internal alkynes and unactivated alkenes is reported. The methodology involves difunctionalization of internal alkynes by using Pd(II) as a catalyst alongwith X-Phos as ligand via 6-endo transesterification and subsequent alkenylation pathway. Notable features include simple and easily available starting materials, including a range of unactivated alkenes, reduced synthetic steps and mild reaction conditions with high efficiency. 相似文献
8.
Relaxation dynamics of plasmons in Au−SiO2 core-shell nanoparticles have been followed by femtosecond pump-probe technique. The effect of excitation pump energy and surrounding medium on the time constants associated with the hot electron relaxation has been elucidated. A gradual increase in the electron-phonon relaxation time with pump energy is observed and can be attributed to the higher perturbation of the electron distribution in AuNPs at higher pump energy. Variation in time constants for the electron-phonon relaxation in different solvents is rationalized on the basis of their thermal conductivities, which govern the rate of dissipation of heat of photoexcited electrons in the nanoparticles. On the other hand, phonon-phonon relaxation is found to be much less effective than electron-phonon relaxation for the dissipation of energy of the excited electron and the time constants associated with it remain unaffected by thermal conductivity of the solvent. 相似文献
9.
Gopal Jeya Ravikumar Dhanalakshmi Murugan Anbarasu Viswanathan Vinitha Vajiravelu Sivamurugan 《印度化学会志》2022,99(1):100291
Chemical recycling of plastic wastes is top among the effective management of the solid wastes. Particularly the post-consumer polyethylene terephthalate (PET) plastic wastes mainly generated from the disposal of beverage bottles and placed third most produced polymeric waste. However, PET wastes could be chemically recycled using several types of homo-/heterogeneous acid or base catalysts, and an effective recycling process has yet to be achieved. Therefore, the present short review is intended to display recent reports on the depolymerization of PET polymer wastes. The review aimed to cover glycolysis and aminolytic depolymerization using various catalytic systems. There is a wide spectrum of catalytic systems such as metal oxides, ionic liquids, organic bases, nanoparticles, porous materials and microwave-assisted rapid depolymerization methods have been developed toward the yield enhancement of the depolymerized products. Ideologically, the present review would benefit the researchers in familiarizing themselves with the latest developments in this field. 相似文献
10.
Synthesis of Small‐Sized,Porous, and Low‐Toxic Magnetite Nanoparticles by Thin POSS Silica Coating 下载免费PDF全文
Dr. Swee Kuan Yen D. Prathyusha Varma Wei Mei Guo Dr. Vincent H. B. Ho Dr. Vimalan Vijayaragavan Dr. Parasuraman Padmanabhan Prof. Kishore Bhakoo Prof. Subramanian Tamil Selvan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(10):3914-3918
In this communication, we report the synthesis of small‐sized (<10 nm), water‐soluble, magnetic nanoparticles (MNPs) coated with polyhedral oligomeric silsesquioxanes (POSS), which contain either polyethylene glycol (PEG) or octa(tetramethylammonium) (OctaTMA) as functional groups. The POSS‐coated MNPs exhibit superparamagnetic behavior with saturation magnetic moments (51–53 emu g?1) comparable to silica‐coated MNPs. They also provide good colloidal stability at different pH and salt concentrations, and low cytotoxicity to MCF‐7 human breast epithelial cells. The relaxivity data and magnetic resonance (MR) phantom images demonstrate the potential application of these MNPs in bioimaging. 相似文献