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11.
Swapnil B. Ambade Rajaram S. Mane Anil V. Ghule Go-Woon Lee Ramphal Sharma Oh-shim Joo Rohan B. Ambade Soo-Hyoung Lee Sung-Hwan Han 《Journal of photochemistry and photobiology. A, Chemistry》2011,217(1):267-270
Enhanced photosensitization in presence of CdS nanoparticles is achieved in electrochemically deposited ZnO nanoplates and N3 loaded dye-sensitized solar cells. Chemically embedded CdS nanoparticles act as a sandwiching layer between ZnO nanoplates and dye molecules by overcoming current limiting serious Zn2+/dye insulating complex formation and CdS photo-corrosion issues. The X-ray diffraction and the scanning electron microscopy confirm the ZnO with vertically aligned nanoplates, perpendicular to the substrate surface. Amorphous CdS is monitored using electron dispersive X-ray analysis. The low and high resolution transmission electron microscope images confirm the presence of CdS nanoparticles over ZnO nanoplates which later is supported by an increase in optical absorbance and shift in band edge. About 400% increase in solar conversion efficiency with this cascade arrangement is achieved when compared with without CdS which could be fascinating while designing solid state solar cells in presence of suitable p-type layer. 相似文献
12.
Yin S Davis RA Shelper T Sykes ML Avery VM Elofsson M Sundin C Quinn RJ 《Organic & biomolecular chemistry》2011,9(19):6755-6760
Bioassay-guided fractionation of the CH(2)Cl(2)/MeOH extract of the Australian marine sponge Pseudoceratina sp. resulted in the purification of four new bromotyrosine alkaloids, pseudoceramines A-D (1-4), along with a known natural product, spermatinamine (5). The structures of 1-5 were determined by spectroscopic methods. Pseudoceramines A (1) and B (2) feature a rare bromotyrosyl-spermine-bromotyrosyl sequence, and pseudoceramine C (3) is the first example of bromotyrosine coupled with an N-methyl derivative of spermidine. Compounds 1-5 were screened for inhibition of toxin secretion by the type III secretion (T3S) pathway in Yersinia pseudotuberculosis. Compounds 2 and 5 inhibited secretion of the Yersinia outer protein YopE (IC(50) = 19 and 6 μM, respectively) and the enzyme activity of YopH (IC(50) = 33 and 6 μM, respectively). 相似文献
13.
Real time PCR is the mainstay of current nucleic acid assays, underpinning applications in forensic science, point-of-care diagnostics and detection of bioterrorism agents. Despite its broad utility, the search for new tests continues, inspired by second and third generation DNA sequencing technologies and fuelled by progress in single molecule fluorescence spectroscopy, nanotechnology and microfabrication. These new methods promise the direct detection of nucleic acids without the need for enzymatic amplification. In this feature article, we provide a chemist's perspective on this multidisciplinary area, introducing the concepts of single molecule detection then focussing on the selection of labels and probe chemistry suitable for generating a signal detectable by ultrasensitive fluorescence spectroscopy. Finally, we discuss the further developments that are required to incorporate these detection platforms into integrated 'sample-in-answer-out' instruments, capable of detecting many target sequences in a matter of minutes. 相似文献
14.
Rohan Abeyaratne 《Journal of Elasticity》1983,13(2):175-184
The equations governing the equilibrium of a finitely deformed elastic solid are derived from the Principle of Minimum Potential Energy. The possibility of the deformation gradient and the stresses being discontinuous across certain surfaces in the body — “equilibrium shocks” — is allowed for. In addition to the equilibrium equations, natural boundary conditions and traction continuity condition, a supplementary jump condition which is to hold across the surface of discontinuity is derived. This condition is shown to imply that a stable equilibrium shock must necessarily be dissipation-free. 相似文献
15.
Chemical investigations of the fermentation broth from the microfungus Xylaria sp. have afforded the new natural product 3-chloro-4-hydroxyphenylacetamide 1 and the previously reported fungal metabolite 3-chloro-4-hydroxyphenylacetic acid 2. This letter reports the isolation and full spectroscopic characterisation of compounds 1 and 2 by NMR, UV, IR and MS data. The crystal structure and one-pot synthesis of 3-chloro-4-hydroxyphenylacetamide are also reported. 相似文献
16.
Hanrahan JR Mewett KN Chebib M Matos S Eliopoulos CT Crean C Kumar RJ Burden P Johnston GA 《Organic & biomolecular chemistry》2006,4(13):2642-2649
A divergent synthesis of both diastereoisomers of (+/-)-(3-aminocyclopentane)alkylphosphinic acid is described. Both diastereoisomers are obtained in 5 steps from the key (+/-)-(3-hydroxycyclopent-1-ene)alkylphosphinate esters which are prepared via a palladium catalysed C-P bond forming reaction. 相似文献
17.
18.
T. Battumur Swapnil B. Ambade Rohan B. Ambade Pashupati Pokharel Dai Soo Lee Sung-Hwan Han Wonjoo Lee Soo-Hyoung Lee 《Current Applied Physics》2013,13(1):196-204
In order to enhance the capacitance of electrochemical capacitors, multiwalled carbon nanotubes (MWCNTs) and graphene nanosheets (GNS) were added to cobalt oxide (Co3O4) paste. The composite film based on Co3O4/MWCNT/GNS (95:4:1 wt%) exhibited a capacitance of 294 F/g while the capacitance of Co3O4/MWCNT (95:5 wt%) and pure Co3O4 film is 205 and 163 F/g, respectively. The enhanced capacitance of Co3O4/MWCNT/GNS composite film was attributed to the electrochemical contributions of the Co3O4 nanoparticle attached to the GNS as well as their significantly increased specific surface areas by MWCNTs. Furthermore, the composite films showed faradaic redox capacitive behavior to double-layer capacitive behavior due to the different nanostructures of the composites. 相似文献
19.
Hamley IW Krysmann MJ Kelarakis A Castelletto V Noirez L Hule RA Pochan DJ 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(36):11369-11375
The self-assembly in aqueous solution of a PEG-peptide conjugate is studied by spectroscopy, electron microscopy, rheology and small-angle X-ray and neutron scattering (SAXS and SANS). The peptide fragment, FFKLVFF is based on fragment KLVFF of the amyloid beta-peptide, Abeta(16-20), extended by two hydrophobic phenylalanine units. This is conjugated to PEG which confers water solubility and leads to distinct self-assembled structures. Small-angle scattering reveals the formation of cylindrical fibrils comprising a peptide core and PEG corona. This constrained structure leads to a model parallel beta-sheet self-assembled structure with a radial arrangement of beta sheets. On increasing concentration, successively nematic and hexagonal columnar phases are formed. The flow-induced alignment of both structures was studied in situ by SANS using a Couette cell. Shear-induced alignment is responsible for the shear thinning behaviour observed by dynamic shear rheometry. Incomplete recovery of moduli after cessation of shear is consistent with the observation from SANS of retained orientation in the sample. 相似文献
20.
Yang Zhou Ruth B. Cink Dr. Rohan S. Dassanayake Prof. Alexander J. Seed Prof. Nicola E. Brasch Prof. Paul Sampson 《Angewandte Chemie (International ed. in English)》2016,55(42):13229-13232
Directly obtaining kinetic and mechanistic data for the reactions of nitroxyl (HNO) with biomolecules (k≈103–107 m ?1 s?1) is not feasible for many systems because of slow HNO release from HNO donor molecules (t1/2 is typically minutes to hours). To address this limitation, we have developed a photoactivatable HNO donor incorporating the (3‐hydroxy‐2‐naphthalenyl)methyl phototrigger, which rapidly releases HNO on demand. A “proof of concept” study is reported, which demonstrates that, upon continuous xenon light excitation, rapid decomposition of the HNO donor occurs within seconds. The amount of HNO generated is strongly dependent on solvent and the rate of the reaction is dependent on the light intensity. 相似文献