http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Reddy, Mudumala Veeranarayana,Lien, Nguyen Thi Kim,Reddy, Gangireddy Chandra Sekhar,Lim, Kwon Taek,Jeong, Yeon Tae The Royal Society of Chemistry 2016 GREEN CHEMISTRY Vol.18 No.15
<P>A novel poly(oligoethylene glycol methacrylate)-g-supported layered double hydroxides (LDHs-g-POEGMA) with high surface area with easy accessibility of active sites was successfully prepared for the first time via an efficient sequential synthetic procedure and characterized by FT-IR spectroscopy, XPS spectra, thermogravimetric analysis (TGA), powder X-ray diffraction (XRD), scanning electron microscopy (SEM), and NMR spectroscopy. The obtained green catalyst was used as an effective, inexpensive, environmentally friendly, and highly active reusable heterogeneous solid catalyst for synthesis of chromene incorporated dihydroquinoline derivatives via a one-pot three-component condensation of 4-hydroxy-2H-chromen-2-one, aromatic amines, and various aldehydes under solvent-free conditions. The notable features of this 'green' reaction are good to excellent yields, shorter reaction times, avoidance of toxic solvents, and substrate diversity. Herein we also observed that the LDHs-g-POEGMA is highly stable under reaction conditions and can be separated easily from the reaction mixture, and, therefore, can be reused for several consecutive runs without any apparent loss in its catalytic activity.</P>
Solution-based spin-coated tin sulfide thin films for photovoltaic and supercapacitor applications
Reddy, B. Purusottam,Sekhar, M. Chandra,Vattikuti, S.V. Prabhakar,Suh, Youngsuk,Park, Si-Hyun Elsevier 2018 Materials research bulletin Vol.103 No.-
<P><B>Abstract</B></P> <P>In this study, tin sulfide (SnS<SUB>x</SUB>) thin films were prepared using a solution-based spin-coating method. The annealing temperature was observed to play a dominant role in determining the phase, crystallinity, and morphology of the SnS<SUB>x</SUB> thin films. The results obtained from X-ray diffraction, as well as optical and electrical measurements, revealed that the films annealed at 500 °C exhibit a pure SnS phase, with a carrier concentration and direct band gap of ∼10<SUP>12</SUP> and 1.4 eV, respectively. To explore the applications of SnS in supercapacitors, electrochemical measurements were performed in a 0.2 M NaOH solution. The results indicated that films with a pure SnS phase have a high specific capacitance of 42 F g<SUP>―1</SUP> at a current density of 2 A g<SUP>―1</SUP>. The synthesized SnS thin films demonstrate potential for applications in electrochemical capacitors and solar cells.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Tin sulfide (SnS<SUB>x</SUB>) thin films were prepared by solution-based spin coating. </LI> <LI> The SnS<SUB>x</SUB> films annealed at 500 °C exhibited a pure SnS phase. </LI> <LI> The films exhibited direct band gap of 1.4 eV which is near to solar maximum. </LI> <LI> The films with the pure SnS phase exhibited a specific capacitance of 42 F g<SUP>―1</SUP>. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>
Sekhar, Kondapalli Venkata Gowri Chandra,Rao, Vajja Sambasiva,Reddy, Aravalli Satish,Sunandini, Ravada,Satuluri, V S A Kumar Korean Chemical Society 2010 Bulletin of the Korean Chemical Society Vol.31 No.5
A simple and efficient method has been developed for conversion of arenecarbaldehyde-3-methylquinoxalin-2-ylhydrazones to 3-(2-methylquinoxalin-3-yl)-2-(substitutedphenyl)thiazolidin-4-ones in good yields using microwave irradiation technique on silica as solid support under solvent free conditions. The synthesized compounds were characterized by elemental microanalysis, infrared spectroscopy, $^1H$ NMR, and mass spectroscopy. All the synthesized thiazolidinones were investigated for their antimicrobial and antifungal activities. The results of the biological activities revealed that the compounds 3b, 3d, 3f and 3h exhibited excellent antibacterial activities while 3d and 3h exhibited good antifungal activity.
Veeranarayana Reddy, M.,Chandra Sekhar Reddy, G.,Thi Kim Lien, N.,Kim, D.W.,Jeong, Y.T. Pergamon Press 2017 Tetrahedron Vol.73 No.10
A facile and efficient method for the synthesis of benzo[4,5]imidazo[1,2-a]pyrimidines has been achieved via highly active and reusable heterogeneous poly acrylic acid-supported layered double hydroxides (PAA-g-LDHs) catalyst promoted one-pot reaction of 1H-benzo[d]imidazol-2-amine, with α,β-unsaturated carbonyl compounds under solvent-free conditions. PAA-g-LDHs catalyst was successfully synthesized via reversible addition-fragmentation chain-transfer polymerization using grafting reaction and was characterized by different analytical techniques. The significant features of this reaction include expedient one-pot process, short reaction time, excellent yields, wide substrate scope and operational simplicity. Also, the catalyst could be reused for several consecutive runs without any apparent loss in its catalytic activity.
Kondapalli Venkata Gowri Chandra Sekhar,Vajja Sambasiva Rao,Aravalli Satish Reddy,Ravada Sunandini,V S A Kumar Satuluri 대한화학회 2010 Bulletin of the Korean Chemical Society Vol.31 No.5
A simple and efficient method has been developed for conversion of arenecarbaldehyde-3-methylquinoxalin-2-ylhydrazones to 3-(2-methylquinoxalin-3-yl)-2-(substitutedphenyl)thiazolidin-4-ones in good yields using microwave irradiation technique on silica as solid support under solvent free conditions. The synthesized compounds were characterized by elemental microanalysis, infrared spectroscopy, 1H NMR, and mass spectroscopy. All the synthesized thiazolidinones were investigated for their antimicrobial and antifungal activities. The results of the biological activities revealed that the compounds 3b, 3d, 3f and 3h exhibited excellent antibacterial activities while 3d and 3h exhibited good antifungal activity.
Quadruple Band-Notched Compact Monopole UWB Antenna for Wireless Applications
Ch. Ramakrishna,G. A. E. Satish Kumar,P. Chandra Sekhar Reddy 한국전자파학회 2021 Journal of Electromagnetic Engineering and Science Vol.21 No.5
A printed quadruple band-notched ultra-wideband (UWB) antenna characteristic is presented. The designed UWB antenna has a size of 32 mm × 30 mm × 1.6 mm and covers an impedance bandwidth off 2.9–14.5 GHz for the entire frequency band. The entire frequency band maintains voltage standing wave ratio (VSWR) < 2, except at WiMAX (3.1–3.6 GHz), WLAN (4.92–6.12 GHz), downlink of Xband for satellite communication systems (7.5–8.4 GHz), and X-band (10.2–11 GHz). By inserting a pair of L-shaped slots into the radiating element, a H-shaped resonator and rectangular split-ring resonators are closely arranged to the microstrip feed-line, alongside the measured impedance bandwidth of 129%. The fabricated antenna radiation pattern and return loss is presented. Key
Enhanced fluorescence efficiency and photocatalytic activity of ZnS quantum dots through Ga doping
Poornaprakash, B.,Chalapathi, U.,Vattikuti, S.V. Prabhakar,Sekhar, M. Chandra,Reddy, B. Purusottam,Poojitha, P.T.,Reddy, M. Siva Pratap,Suh, Youngsuk,Park, Si-Hyun Elsevier Science B.V., Amsterdam. 2019 Ceramics international Vol.45 No.no.pa