排序方式: 共有22条查询结果,搜索用时 15 毫秒
1.
Myint MT Kitsomboonloha R Baruah S Dutta J 《Journal of colloid and interface science》2011,354(2):810-815
The synthesis and properties of superhydrophobic surfaces based on binary surface topography made of zinc oxide (ZnO) microrod-decorated micropatterns are reported. ZnO is intrinsically hydrophilic but can be utilized to create hydrophobic surfaces by creating artificial roughness via microstructuring. Micron scale patterns consisting of nanocrystalline ZnO seed particles were applied to glass substrates with a modified ink-jet printer. Microrods were then grown on the patterns by a hydrothermal process without any further chemical modification. Water contact angle (WCA)(1) up to 153° was achieved. Different micro array patterned surfaces with varying response of static contact angle or sessile droplet analysis are reported. 相似文献
2.
We report a study on the effect of seeding on glass substrates with zinc oxide nanocrystallites towards the hydrothermal growth
of ZnO nanorods from a zinc nitrate hexahydrate and hexamethylenetetramine solution at 95 °C. The seeding was done with pre-synthesized
ZnO nanoparticles in isopropanol with diameters of about 6–7 nm as well as the direct growth of ZnO nanocrystallites on the
substrates by the hydrolysis of pre-deposited zinc acetate film. The nanorods grown on ZnO nanoparticle seeds show uniform
dimensions throughout the substrate but were not homogenously aligned vertically from the substrate and appeared like nanoflowers
with nanorod petals. Nanorods grown from the crystallites formed in situ on the substrates displayed wide variations in dimension
depending upon the preheating and annealing conditions. Annealing the seed crystals below 350 °C led to scattered growth directions
whereupon preferential orientation of the nanorods perpendicular to the substrates was observed. High surface to volume ratio
which is vital for gas sensing applications can be achieved by this simple hydrothermal growth of nanorods and the rod height
and rod morphology can be controlled through the growth parameters. 相似文献
3.
Ashis Saha Sai Madhav Modumudi Sunandan Gangopadhyay 《General Relativity and Gravitation》2018,50(8):103
We introduce the noncommutative geometry inspired Ayón Beato García black hole metric and study various properties of this metric by which we try to probe the allowed values of the noncommutative parameter \(\vartheta \) under certain conditions. We then construct the shadow (apparent shape) cast by this black hole. We derive the corresponding photon orbits and explore the effects of noncommutative spacetime on them. We then study the effects of noncommutative parameter \(\vartheta \), smeared mass m(r), smeared charge q(r) on the silhouette of the shadow analytically and present the results graphically. We then discuss the deformation which arises in the shape of the shadow under various conditions. Finally, we introduce a plasma background and observe how the shadow behaves in this scenario. 相似文献
4.
Diganta Parai Debabrata Ghorai Sunandan Gangopadhyay 《General Relativity and Gravitation》2018,50(11):149
In this paper, we analytically investigate the noncommutative effects of a charged black hole on holographic superconductors in the probe limit. The effects of charge of the black hole is investigated in our study. Employing the Sturm–Liouville eigenvalue method, the relation between the critical temperature and charge density is analytically investigated. The condensation operator is then computed. It is observed that condensate gets harder to form for large values of charge of the black hole. 相似文献
5.
Abhijit Dutta Sunandan Gangopadhyay 《International Journal of Theoretical Physics》2016,55(6):2746-2754
In this paper, we have investigated the thermodynamics of Schwarzschild and Reissner-Nordström black holes using the symmetric generalised uncertainty principle which contains correction terms involving momentum and position uncertainty. The mass-temperature relationship and the heat capacity for these black holes have been computed using which the critical and remnant masses have been obtained. The entropy is found to satisfy the area law upto leading order logarithmic corrections and corrections of the form A2 (which is a new finding in this paper) from the symmetric generalised uncertainty principle. 相似文献
6.
Sunandan Gangopadhyay 《General Relativity and Gravitation》2010,42(5):1183-1187
We apply the covariant anomaly cancellation method to compute the Hawking fluxes from the event and cosmic horizons of the
Schwarzschild–de Sitter black hole. The derivation is new from the existing ones as we split the space in three different
regions (near to and away from the event and cosmic horizons) and write down the covariant energy–momentum tensor using three
step functions which covers the whole region leading elegantly to the conditions required to compute the Hawking fluxes from
the event and cosmic horizons. 相似文献
7.
A novel biocompatible chitosan passivated manganese doped zinc sulfide (Mn doped ZnS) nanophosphor has been synthesized through
a simple aqueous precipitation reaction. Upon excitation with ultraviolet light, the quantum dots (QDs) emit an orange luminescence
peaking at 590 nm, which is visible to the naked eye. These chitosan coated Mn doped ZnS QDs can have potential applications
in bio-labeling, particularly in fluorescence-based imaging. One of the envisioned applications of these QDs is in improving
the conventional, organic dye-reliant Fluorescence in situ Hybridization (FISH) technique, a widely used method for microbial
detection. Here we demonstrate that the chitosan-capped Mn doped ZnS QDs are suitable for this purpose. 相似文献
8.
Phytochemical Screening on Mussaenda Philipica Sepals — Isolation of Iridoid Glycosides and Flavones
Kamurthy Hemalatha Viddae Jeteindra Dontha Sunitha Rao Nandyla Sunandan Nampally Shivaji 《平面色谱法杂志一现代薄层色谱法》2014,27(2):93-96
JPC – Journal of Planar Chromatography – Modern TLC - Three iridoid glycosides, 5-hydroxy davisioside (1), 4-acetoxy-7-methoxy secologanin (4) and 6-methoxy mussaenoside (5) as well as... 相似文献
9.
We calculate the Komar energy E for a noncommutative inspired Schwarzschild black hole. A deformation from the conventional identity E = 2ST H is found in the next to leading order computation in the noncommutative parameter θ (i.e. \({\mathcal{O}(\sqrt{\theta}e^{-M^2/\theta})}\)) which is also consistent with the fact that the area law now breaks down. This deformation yields a nonvanishing Komar energy at the extremal point T H = 0 of these black holes. We then work out the Smarr formula, clearly elaborating the differences from the standard result M = 2ST H , where the mass (M) of the black hole is identified with the asymptotic limit of the Komar energy. Similar conclusions are also shown to hold for a deSitter–Schwarzschild geometry. 相似文献
10.
Rituparna Mandal Sukanta Bhattacharyya Sunandan Gangopadhyay 《General Relativity and Gravitation》2018,50(11):143
We study the phase transition of rainbow inspired higher dimensional Schwarzschild black hole incorporating the effects of the generalized uncertainty principle. First, we obtain the relation between the mass and Hawking temperature of the rainbow inspired black hole taking into account the effects of the modified dispersion relation and the generalized uncertainty principle. The heat capacity is then computed from this relation which reveals that there are remnants. The entropy of the black hole is next obtained in \(3+1\) and \(4+1\)-dimensions and is found to have logarithmic corrections only in \(3+1\)-dimensions. We further investigate the local temperature, free energy and stability of the black hole in an isothermal cavity. From the analysis of the free energy, we find that there are two Hawking–Page type phase transitions in \(3+1\) and \(4+1\)-dimensions if we take into account the generalized uncertainty principle. However, in the absence of the generalized uncertainty principle, only one Hawking–Page type phase transition exists in spacetime dimensions greater than four. 相似文献