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101.
Complex dielectric spectroscopy (frequency range 5 Hz-13 MHz) has been used to analyse the frequency, temperature and bias-field dependences of the molecular dynamics of a very high-spontaneous-polarization ferroelectric liquid crystalline material exhibiting SmA, SmC* and unknown SmX smectic phases. Different smectic phase transition temperatures have been observed from the study of the temperature dependence of the dielectric strength and the relaxation frequency. The phase transition temperatures (crystalline to isotropic phases) have also been described very accurately from the temperature-dependent symmetric and asymmetric shape parameters of the relaxation function and also the dc conductivity. In a planar aligned cell, two symmetric modes (Goldstone mode and domain mode) have been observed in both the SmX and SmC* phases. One asymmetric mode (X-mode) observed in the SmC* and SmA phases could be related to the interaction of dipoles of the ferroelectric liquid crystals being affected by the surface of the cell. The soft mode, which usually appears very close to the SmC*-SmA phase transition was not observed until the bias field was applied. The second order nature of the SmC*-SmA phase transition was revealed. 相似文献
102.
Two-component thermo-responsive hydrogels poly(N-isopropylacrylamide)-co-vinylbenzyltrimethylammonium chloride (NIPA-co-VBT) and poly(N-isopropylacrylamide)-co-p-sodium styrene sulphonate (NIPA-co-SSS) were prepared by using high energy gamma radiation. The gels were characterized by Fourier transformed infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and sol-gel analysis. The presence of ionic monomers in NIPA leads to lower gel content. Introduction of ionic components in the matrix enhanced swelling extent but caused slower volume transition. The swelling studies in alcohol indicated that swelling extent was function of polarity of the swelling medium and all gels followed the order water > methanol > ethanol > iso-propanol. In mixed co-solvents (water-alcohol), they exhibit complex reentrant behavior. The co-polymer gels containing VBT swelled faster and to higher extent than those containing SSS. The dynamic swelling studies indicated that diffusion of water in PNIPA gel shifts from Fickian for PNIPA to anomalous for NIPA-co-ionic gels also the mean swelling time (MST) decreases for gels containing ionic monomers. 相似文献
103.
Proton and alpha particle spectra have been measured in the 12C+93Nb and 12C+58Ni reactions at E(12C)=40 and 50 MeV and in the 16O + 93Nb reaction at E(16O) =75 MeV. The spectra are compared with the statistical model calculations. The shapes of the calculated spectra are in
agreement with experimental data except for the alpha spectrum in the 12C + 93Nb reaction at 40 MeV. The observed evaporation bump is at ∼2 MeV lower energy compared to the calculated one. This discrepancy
could imply alpha particle emission from a deformed configuration before compound nucleus formation at this near Coulomb barrier
beam energy. 相似文献
104.
A Jayanth Kumar N M Gowri R Venkateswara Raju G Nirmala B S Bellubbi T Radha Krishna 《Pramana》2006,67(2):383-387
Over the last two decades, the fiber optic technology has passed through many analytical stages. Some commercially available
fiber optic sensors, though in a small way, are being used for automation in mechanical and industrial environments. They
are also used for instrumentation and controls.
In the present work, an intensity-modulated intrinsic fiber optic sugar sensor is presented. This type of sensor, with slight
modification, can be used for on-line determination of the concentration of sugar content in sugarcane juice in sugar industry.
In the present set-up, a plastic fiber made of polymethylmethacrylate is used. A portion of the cladding (1 cm, 2 cm, 3 cm)
at the mid-point along the length of the fiber is removed. This portion is immersed in sugar solution of known concentration
and refractive index. At one end of the fiber an 850 nm source is used and at the other end a power meter is connected. By
varying the concentration of sugar solution, the output power is noted. These studies are made due to the change in refractive
index of the fluid. The device was found to be very sensitive which is free from EMI and shock hazards, stable and repeatable
and they can be remotely interfaced with a computer to give on-line measurements and thus become useful for application in
sugar industries. 相似文献
105.
Anil Kumar Karn 《Positivity》2007,11(2):369-374
An error has been detected (and also corrected) in Theorem 2.8 of the paper entitled “Adjoining an Order Unit to a Matrix
Ordered Space” (Positivity, (2005)9: 207–223; DOI ). Accordingly, some of the results of the paper have been modified. Also, a notion of C*-matricially, Riesz normed spaces has been introduced. 相似文献
106.
107.
According to Bell's theorem, the degree of correlation between spatially separated measurements on a quantum system is limited by certain inequalities if one assumes the condition of locality. Quantum mechanics predicts that this limit can be exceeded, making it nonlocal. We analyse the effect of an environment modelled by a fluctuating magnetic field on the quantum correlations in an EPR singlet as seen in the Bell inequality. We show that in an EPR setup, the system goes from the usual ‘violation’ of Bell's inequality to a ‘non-violation’ for times larger than a characteristic time scale which is related to the parameters of the fluctuating field. We also look at these inequalities as a function of the spatial separation between the EPR pair. 相似文献
108.
Anjos JC Appel JA Bean A Bracker SB Browder TE Cremaldi LM Duboscq JE Elliott JR Escobar CO Gibney MC Hartner GF Karchin PE Kumar BR Losty MJ Luste GJ Mantsch PM Martin JF McHugh S Menary SR Morrison RJ Nash T Ong P Pinfold J Punkar G Purohit MV Santoro AF Sidhu JS Sliwa K Sokoloff MD Souza MH Spalding WJ Streetman ME Stundia AB Witherell MS 《Physical review letters》1990,64(24):2885-2888
109.
Adamovich MI Aggarwal MM Alexandrov YA Ameeva ZV Andreeva NP Anzon ZV Arora R Badyal SK Bhalla KB Bhasin A Bhatia VS Bubnov VI Burnett TH Cai X Chasnikov IY Chernova LP Chernyavski MM Dressel B Eligbaeva GZ Eremenko LE Friedlander EM Gadzhieva SI Gaitinov AS Ganssauge ER Garpman S Gerassimov SG Gill A Grote JG Gulamov KG Gulyamov UG Gupta VK Hackel S Heckman HH Haung H Judek B Kachroo S Kadyrov FG Kalyachkina GS Kanygina EK Kaul GL Kaur M Kharlamov SP Koss T Kumar V Lal P Larionova VG 《Physical review letters》1990,65(4):412-415
110.
Anjos JC Appel JA Bean A Bracker SB Browder TE Cremaldi LM Elliott JR Escobar CO Estabrooks P Gibney MC Hartner GF Karchin PE Kumar BR Losty MJ Luste GJ Mantsch PM Martin JF McHugh S Menary SR Morrison RJ Nash T Nauenberg U Ong P Pinfold J Punkar G Purohit MV Raab JR Santoro AF Sidhu JS Sliwa K Sokoloff MD Souza MH Spalding WJ Streetman ME Stundia AB Witherell MS 《Physical review letters》1988,60(14):1379-1381