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41.
Ram Manohar Yadav Dinesh Pratap Singh T. Shripathi O. N. Srivastava 《Journal of nanoparticle research》2008,10(8):1349-1354
We report the observations made on the synthesis and characterization of C–N nanotube blocks and Y-junctions in bamboo-like
C–N nanotubes. The C–N nanotube Blocks have been synthesized by pyrolyzing the mixture of silver nitrate acetonitrile solution
and ferrocene benzene solution. The structural/microstructural characterization of the as-synthesized material has been done
using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). X-ray photoelectron spectroscopic (XPS)
analysis has been carried out to confirm the presence of nitrogen in nanotubes. These investigations reveal the formation
of blocks of bamboo-like nanotubes having the dimension 300 × 200 × 30 μm and the diameter is 20–50 nm. We also observe the
formation of Y-junctions in bamboo-like nanotubes as we spray the acetonitrile ferrocene and AgNO3 mixture. The length of the synthesized Y-junction nanotube bundles is ~2 μm. Some more complex Ψ-shaped junctions are also
found to be present. The diameters of the Y-junction nanotubes is ~80 nm at the junction and 25–50 nm at the branches. 相似文献
42.
Deoshree Baghmar Neeraj K. Gaur Dinesh C. Gupta Sadhana Singh 《Central European Journal of Physics》2008,6(3):445-449
The structural changes within the Silver iodide (AgI) and Copper iodide (CuI) induced by pressure have been investigated using
an effective interaction potential. CuI and AgI in their parent zinc blende (ZnS) to rock salt (NaCl) through an intermediate
structure have been reported. The calculated values for the phase transition pressures and associate volume collapses are
generally in good agreement with measured data.
相似文献
43.
Sarma DD Topwal D Manju U Krishnakumar SR Bertolo M La Rosa S Cautero G Koo TY Sharma PA Cheong SW Fujimori A 《Physical review letters》2004,93(9):097202
We use a spatially resolved, direct spectroscopic probe for electronic structure with an additional sensitivity to chemical compositions to investigate high-quality single crystal samples of La(1/4)Pr(3/8)Ca(3/8)MnO3, establishing the formation of distinct insulating domains embedded in the metallic host at low temperatures. These domains are found to be at least an order of magnitude larger in size compared to previous estimates and exhibit memory effects on temperature cycling in the absence of any perceptible chemical inhomogeneity, suggesting long-range strains as the probable origin. 相似文献
44.
The observed frequency dependent optical response of hole doped cuprate La1.85Sr0.15CuO4 superconductors, has been theoretically analysed. Starting from an effective two-dimensional (2D) interaction potential for superlattice of hole doped cuprates treated as a layered electron gas, the spectral function is formulated. Calculations of the optical conductivity σ(ω) have been made within the two-component scheme: one is the coherent Drude carriers responsible for superconductivity and the other is incoherent motion of carriers from one site to other leads to a pairing between Drude carriers. The approach accounts for the anomalies reported (frequency dependence of optical conductivity) in the optical measurements for the normal state. Estimating the effective mass from specific heat measurement and ε∞ from band structure calculations for the low-energy charge density waves, the model has only one free parameter, the relaxation rate. The frequency dependent relaxation rates are expressed in terms of memory functions, and the coherent Drude carriers from the effective interaction potential lead to a sharp peak at zero frequency and a long tail at higher frequencies, i.e. in the infrared (IR) region. However, the hopping of carriers from one site to other (incoherent motion of doped carriers) yields a peak value in the optical conductivity centred at mid-IR (MIR) region. We find that both the Drude and hopping carriers in the superlattice of cuprates will contribute to the optical process of conduction in the CuO2 planes and shows similar results on optical conductivity in the MIR as well as IR frequency regions as those revealed from experiments. 相似文献
45.
We calculate the net-baryon rapidity distribution in Au+Au collisions at the Relativistic Heavy Ion Collider (RHIC) in the framework of the parton cascade model (PCM). Parton rescattering and fragmentation leads to a substantial increase in the net-baryon density at midrapidity over the density produced by initial primary parton-parton scatterings. The PCM is able to describe the measured net-baryon density at RHIC. 相似文献
46.
An efficient synthesis of 5‐arylidine‐2,4‐thiazolidinediones has been developed using dicationic ionic liquid as green medium and catalyst. This method performed well for the condensation of both aryl as well as heteryl aldehydes with 2,4‐thiazolidinedione and gave 5‐arylidine‐2,4‐thiazolidinediones with excellent yields. 相似文献
47.
Harsh Kumar Kanchan Bhardwaj Natlia Cruz-Martins Eugenie Nepovimova Patrik Oleksak Daljeet Singh Dhanjal Sonali Bhardwaj Reena Singh Chirag Chopra Rachna Verma Prem Parkash Chauhan Dinesh Kumar Kamil Ku
a 《Molecules (Basel, Switzerland)》2021,26(11)
The ingestion of contaminated water and food is known to cause food illness. Moreover, on assessing the patients suffering from foodborne disease has revealed the role of microbes in such diseases. Concerning which different methods have been developed for protecting food from microbes, the treatment of food with chemicals has been reported to exhibit an unwanted organoleptic effect while also affecting the nutritional value of food. Owing to these challenges, the demand for natural food preservatives has substantially increased. Therefore, the interest of researchers and food industries has shifted towards fruit polyphenols as potent inhibitors of foodborne bacteria. Recently, numerous fruit polyphenols have been acclaimed for their ability to avert toxin production and biofilm formation. Furthermore, various studies have recommended using fruit polyphenols solely or in combination with chemical disinfectants and food preservatives. Currently, different nanoparticles have been synthesized using fruit polyphenols to curb the growth of pathogenic microbes. Hence, this review intends to summarize the current knowledge about fruit polyphenols as antibacterial agents against foodborne pathogens. Additionally, the application of different fruit extracts in synthesizing functionalized nanoparticles has also been discussed. 相似文献
48.
49.
The first synthesis of 1,3-oxaselenepane derivatives by the reaction of aryl isoselenocyanates with 4-bromobutanol in the presence of sodium hydride in THF as a one-pot reaction is described. The Z/E isomerism for the exocyclic carbon-nitrogen double bond in the selenium heterocycles was observed for the first time. 相似文献
50.
Chang-Ching Chan Mark S. Bolgar Scott A. Miller Athula B. Attygalle 《Journal of the American Society for Mass Spectrometry》2010,21(9):1554-1560
An ambient pressure ionization technique for mass spectrometric analysis of substances present on solid surfaces was developed.
A nebulized spray containing molecular ions of a solvent such as toluene can be generated by passing the solvent through a
stainless steel capillary held at a high voltage. When the stream of charged droplets produced in this way is directed onto
a solid surface, the analytes present on the surface are desorbed and ionized by a charge exchange process. This technique
was shown to desorb and generate positively charged molecular ions from compounds that are not readily ionized by some other
ambient methods, under positive-ion generation mode. For example, intense signals representing radical cations of 1,4-hydroquinone,
limonene, thymol, and several other compounds were observed when the analytes were deposited on a metal surface and exposed
to a toluene spray nebulized from the metal capillary maintained at a potential of about +5 kV. In contrast, when the same
samples were exposed to a spray of water/methanol/formic acid under customary DESI-like (positive-ion mode) conditions, no
peaks representing the analytes were observed. 相似文献