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991.
Mini PA Balakrishnan A Nair SV Subramanian KR 《Chemical communications (Cambridge, England)》2011,47(20):5753-5755
We report on the development and characterization of high performance supercapacitor electrodes synthesized using electrophoretic deposition of graphene, upon which the poly(pyrrole)-layer was electropolymerised. The highly capacitive electrode had a specific capacitance of 1510 F g(-1), area capacitance of 151 mF cm(-2) and volume capacitance of 151 F cm(-3) at 10 mV s(-1). 相似文献
992.
Two couples of low pressure multi-wire proportional chambers (MWPC) were located in the target chamber to detect fission fragments in a hypernuclei producing experiment at Thomas Jefferson National Laboratory (Jlab). In the experiment, a continuous wave (CW) electron beam was applied to form hypernuclei by electromagnetic interaction. In the target chamber, the high energy (1.853 GeV) and high intensity (500 nA) primary electron beam caused a high particle background, which influenced the detection of the fission fragments. This report described the design of the MWPCs and studied the fission-fragment detecting performance of them under such a high background. The efficiency of the MWPCs was given with the help of a high resolution kaon spectrometer. At the same time, the background particles were discussed with a Monte Carlo code based on GEANT4. 相似文献
993.
We consider a general image sensing framework that includes many quantum sensing problems by an appropriate choice of image set, prior probabilities, and cost function. For any such problem, in the presence of loss and a signal energy constraint, we show that a pure input state of light with the signal modes in a mixture of number states minimizes the cost among all ancilla-assisted parallel strategies. Lossy binary phase discrimination with a peak photon number constraint and general lossless image sensing are considered as examples. 相似文献
994.
C. V. Yelamaggad S. Anitha Nagamani Uma S. Hiremath Geetha G. Nair 《Liquid crystals》2013,40(7):1009-1015
Chiral non-symmetric dimeric liquid crystals consisting of a cholesteryl ester moiety as chiral entity and a biphenyl aromatic core, interconnected through n-butyl (C4) or n-pentyl (C5) parity alkylene spacers, have been synthesized and investigated for their liquid crystalline properties. All the dimers exhibit enantiotropic mesophases. The first member of the dimers having the C4 central spacer exhibit only the chiral nematic (N*) mesophase, while the higher homologues also show smectic A (SmA) and twist grain boundary (TGB) mesophases. The dimers of the other series containing the C5 central spacer also have stable SmA, TGB and N* mesophases, except for the first which does not show the TGB phase. Both series of compounds show a weak odd-even effect with terminal alkyl chain substitution, while the spacer length has a marked influence on the phase transition temperatures. 相似文献
995.
Electro-optical and polarization current measurements on 1,3-phenylene-bis[4-(3-fluoro-4-decyloxyphenyliminomethyl) benzoate] (3F-10-O-PIMB) revealed a second order phase transition between two antiferroelectric ‘smectic banana’ phases. The observations show that the switching between the ferroelectric states in the higher temperature (HT) phase requires higher thresholds than in the lower temperature (LT) phase. It is hypothesized that the HT phase has a lower (triclinic, C1) symmetry, than that of the LT phase (monoclinic, C2). It is also shown that electric fields can induce transitions between different ‘smectic banana’ phases. 相似文献
996.
C. V. Yelamaggad S. Anitha Nagamani Geetha G. Nair D. S. Shankar Rao S. Krishna Prasad A. Jakli 《Liquid crystals》2013,40(9):1181-1185
The first achiral bent-core banana-shaped bidentate ligands and their Cu(II) and Pd(II) metal complexes have been synthesized and investigated for mesomorphic behaviour. The bidentate ligands exhibit only one enantiotropic mesophase. The ligand having C6 -alkoxy chains shows a mesophase that has been assigned as a two-dimensional B1 phase while the C8 and C10 homologues stabilize the fluid B2 mesophase showing antiferroelectric switching characteristics. In constrast, their corresponding Cu(II) and Pd(II) metal complexes are non-mesomorphic. 相似文献
997.
998.
S. Balaji B. K. Panigrahi K. Saravanan C. David S. Amirthapandian S. Kalavathi K. G. M. Nair René Hübner 《Applied Physics A: Materials Science & Processing》2014,116(4):1595-1603
Fine Co and Pt nanoparticles are nucleated when a silica sample is implanted with 400 keV Co+ and 1370 keV Pt+ ions. At the implanted range, Co and Pt react to form small Co x Pt(1?x) nanoparticles during Si+ ion irradiation at 300 °C. Thermal annealing of the pre-implanted silica substrate at 1000 °C results in the formation of spherical nanoparticles of various sizes. When irradiated with Si+ ions at 300 °C, particles in the size range of 5–17 nm undergo rod-like shape transformation with an elongation in the direction of the incident ion beam, while those particles in the size range of 17–26 nm turn into elliptical shape. Moreover, it is suspected that very big nanoparticles (size >26 nm) decrease in size, while small nanoparticles (size <5 nm) do not undergo any transformation. During Si+ ion irradiation, the crystalline nature of the nanoparticles is preserved. The results are discussed in the light of the thermal spike model. 相似文献
999.
Ajeet Kaushik Rajesh Kumar Eric Huey Shekhar Bhansali Narayana Nair Madhavan Nair 《Mikrochimica acta》2014,181(15-16):1759-1780
This review (with 129 refs.) gives an overview on how the integration of silica nanowires (NWs) into micro-scale devices has resulted, in recent years, in simple yet robust nano-instrumentation with improved performance in targeted application areas such as sensing. This has been achieved by the use of appropriate techniques such as di-electrophoresis and direct vapor-liquid-growth phenomena, to restrict the growth of NWs to site-specific locations. This also has eliminated the need for post-growth processing and enables nanostructures to be placed on pre-patterned substrates. Various kinds of NWs have been investigated to determine how their physical and chemical properties can be tuned for integration into sensing structures. NWs integrated onto interdigitated micro-electrodes have been applied to the determination of gases and biomarkers. The technique of directly growing NWs eliminates the need for their physical transfer and thus preserves their structure and performance, and further reduces the costs of fabrication. The biocompatibility of NWs also has been studied with respect to possible biological applications. This review addresses the challenges in growth and integration of NWs to understand related mechanism on biological contact or gas exposure and sensing performance for personalized health and environmental monitoring. Figure
Silica nanowires decorated micro-electrodes for sensing application 相似文献
1000.
J. P. Nair P. Surendran Hillary Sparrow A. K. Gupta P. V. Bhagwat S. Kailas V. M. Datar 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(2):947-950
Track etch membranes (TEMs) program at 14 UD Pelletron accelerator at TIFR, Mumbai, India using 25 micron thick polyethylene terepthalate film is described. Large scale preparation of TEMs by scanning heavy ion beams using a electromagnetic scanner and rolling mechanism using a geared D.C. motor and vacuum rotary feed through are presented. The selection of ions of suitable energy and etching parameters for making various pore sizes were investigated using Rutherford scattered beam from Pelletron accelerator. Pore size and pore density were measured using scanning electron microscope. Scanning width up to 35 cm and irradiation up to 22 m were successfully carried out using this facility. Some applications carried out using these membranes are also mentioned. 相似文献