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991.
Extended inflation solution in Brans-Dicke theory given by Mathiazhagan and Johri (MJ) is shown as the unique solution only
if the scale factor is assumed to be a power function of the scalar field. Only the consistent solution amongst the set of
solutions given by Patra, Roy and Ray is found identical to the MJ solution. Both exponential inflation and power function
inflation are studied in general scalar tensor theory where the parameter to is a function of the scalar, field. It is noted
that exponential inflation is forbidden in Brans-Dicke theory wherew is a constant. 相似文献
992.
Swadeshmukul Santra Bernd Liesenfeld Debamitra Dutta Weihong Tan Robert A. Mericle 《Journal of luminescence》2006,117(1):75-82
In this paper, we described a novel fluorescence lifetime-based approach to determine the core-shell nanostructure of FITC-(fluorescein isothiocyanate, isomer I) doped fluorescent silica nanoparticles (FSNPs). Because of phase homogeneity between the core and the shell, electron microscopic technique could not be used to characterize such core-shell nanostructure. Our optical approach not only revealed the core-shell nanostructure of FSNPs but also evaluated photobleaching of FSNPs both in the solvated and non-solvated (dry) states. The FSNPs were produced via Stöber's method by hydrolysis and co-condensation reaction of tetraethylorthosilicate (TEOS) and fluorescein linked (3-aminopropyl)triethoxysilane (FITC-APTS conjugate) in the presence of ammonium hydroxide catalyst. To obtain a pure silica surface coating, FSNPs were then post-coated with TEOS. The average particle size was 135 nm as determined by TEM (transmission electron microscope) measurements. Fluorescence excitation and emission spectral data demonstrated successful doping of FITC dye molecules in FSNPs. Fluorescence lifetime data revealed that approximately 62% of dye molecules remained in the solvated silica shell, while 38% of dye molecules remained in the non-solvated (dry) silica core. Photobleaching experiments of FSNPs were conducted both in DI water (solution state) and in air (dry state). Severe photobleaching of FSNPs was observed in air. However, FSNPs were moderately photostable in the solution state. Photostability of FSNPs in both solution and dry states was explained on the basis of fluorescence lifetime data. 相似文献
993.
Shashwati Sen DK Aswal Ajay Singh TV Chandrasekhar Rao KP Muthe JC Vyas LC Gupta SK Gupta VC Sahni 《Pramana》2002,58(5-6):867-870
The MgB2 superconductor, synthesized using solid-state and liquid-phase sintering methods, have been characterized for various properties.
The upper critical field, irreversibility line and critical current density have been determined using magnetization data.
The current-voltage characteristics recorded under an applied magnetic field revealed the existence of vortex glass transition.
The surface analysis using X-ray photoelectron spectroscopy shows that MgB2 is sensitive to atmospheric degradation. 相似文献
994.
In this article we discuss the conditions required to guarantee the non-emptiness and the boundedness of certain subsets of the set of Lagrange multipliers for an inequality and equality constrained vector minimization problem. 相似文献
995.
This paper describes the techniques adopted for visualization of Rayleigh–Benard convection during solidification of eutectic, hypo- and hyper-eutectic salt solutions. Neutrally buoyant hollow glass spheres were inducted in the body of the solidifying salt solution. The convection currents were captured by scattering of a laser beam by these beads. The apparatus has two components, namely: (i) measurement of interface/mushy region movement and temperature distribution and (ii) flow visualization with laser beam scattered by hollow glass spheres. The distinct nature of convection cells in the eutectic and hypo eutectic region is brought out. 相似文献
996.
Ultra heavy (UH) cosmic rays of Z65 are produced either by s- or r-process of nucleosynthesis. Since these two processes occur under different astrophysical environments, the relative abundances of UH ions could be an important parameter in finding their source and origin. Data analysis is carried out on four detector stacks exposed in space by UH cosmic ray experiment on board LDEF. Scanning and analysis of 0.21 m2 detector area resulted in finding of 72 UH ions (68Z96) including two actinides (88Z100). The ratio of actinides to that of sub-actinides is found to be 0.034±0.024, which is well within the observational limits of other experiments. Results suggest possible sources, which predominantly ejects r-process synthesized material. 相似文献
997.
Naba K. Mondal Saurabh D. Rindani Kaustubh Agashe Pankaj Agrawal B. Ananthanarayan Ketevi Assamagan Alfred Bartl Subhendu Chakrabarti Utpal Chattopadhyay Debajyoti Choudhury Eung-Jin Chun Prasanta K. Das Siba P. Das Amitava Datta Sukanta Dutta Jeff Forshaw Thomas Gajdosik Dilip K. Ghosh Rohini M. Godbole Monoranjan Guchait Partha Konar Sabine Kraml Manas Maity Kajari Mazumdar Naba K. Mondai Biswarup Mukhopadhyaya Meenakshi Narain Santosh K. Rai Sreerup Raychaudhuri Saurabh D. Rindani D. P. Roy Seema Sharma Ritesh K. Singh Rishikesh Vaidya 《Pramana》2004,63(6):1331-1353
This is a summary of the projects undertaken by the working group I on high energy and collider physics. 相似文献
998.
999.
In this article we study approximate optimality in the setting of a Banach space. We study various solution concepts existing
in the literature and develop very general necessary optimality conditions in terms of limiting subdifferentials. We also
study saddle point conditions and relate them to various solution concepts.
Part of this research was carried out when the author was a post-doctoral fellow at UAB, Barcelona by the Grant No. SB99-B0771103B
of the Spanish Ministry of Education and Culture. The hospitality and the facilities provided at CODE, UAB is gratefully acknowledged. 相似文献
1000.
Bishnupada Dutta 《Tetrahedron letters》2006,47(3):377-379
A simple and useful method for the synthesis of various 2-substituted quindolines starting from 2-nitroacetophenone is described. 相似文献