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951.
Patil Atul S. Patil Kailas P. Patil Anil B. Kulkarni Pallavi M. Chandegaonkar Vijay R. More Bhausaheb P. Mane Dhananjay V. 《平面色谱法杂志一现代薄层色谱法》2019,32(1):69-71
JPC – Journal of Planar Chromatography – Modern TLC - 相似文献
952.
Balasubramanian Rukmanikrishnan Satish Kumar Rajasekharan Jintae Lee Jaewoong Lee 《先进技术聚合物》2019,30(11):2750-2758
Binary composite films were prepared from agar (A) and xanthan gum (X) with different weight percentages. The composite films were transparent, lightweight, eco‐friendly, and biodegradable. The structure and morphology of the prepared agar and AX composite films were confirmed by Fourier transform infrared spectroscopy (FT‐IR), X‐ray powder diffraction (XRD), and scanning electron microscopy (SEM) technique. The glass transition temperature (Tg) and melting temperature (Tm) of the AX composite films was slightly improved, when compared with the neat agar. Thermogravimetric analysis (TGA) analysis showed a considerable increment in the char yield and an improved thermal stability. The tensile strength was in the range of 25 to 40 MPa, and elongation at break was in the range of 28.9 to 39.4%. Though, the water vapor permeability (WVP) value reduced in the composite films the difference was not significant. From the mechanical studies, we can deduce that agar and xanthan gum are compatible and miscible with one another leading to prospects of their composite films being considered for different biomedical and packaging applications. 相似文献
953.
Pammi Praneetha Ankit Balhara Mayur K. Ladumor Dilip Kumar Singh Amol Patil Jalvadi Preethi Sunil Pokharkar Abhijeet Yashwantrao Deshpande Sanjeev Giri Saranjit Singh 《Journal of mass spectrometry : JMS》2019,54(9):738-749
Black pepper, though commonly employed as a spice, has many medicinal properties. It consists of volatile oils, alkaloids, pungent resins, etc., of which piperine is a major constituent. Though safe at low doses, piperine causes alteration in the activity of drug metabolising enzymes and transporters at high dose and is known to precipitate liver toxicity. It has a potential to form reactive metabolite(s) (RM) owing to the presence of structural alerts, such as methylenedioxyphenyl (MDP), α, β‐unsaturated carbonyl group (Michael acceptor), and piperidine. The present study was designed to detect and characterize stable and RM(s) of piperine formed on in vitro incubation with human liver microsomes. The investigation of RMs was done with the aid of trapping agents, viz, glutathione (GSH) and N‐acetylcysteine (NAC). The samples were analysed by ultra‐high performance liquid chromatography coupled with high resolution mass spectrometry (UHPLC‐HRMS) using Thermo Scientific Q Exactive Plus Orbitrap. Full scan MS followed by data‐dependent MS2 (Full MS‐ddMS2) mode was used to establish mass spectrometric fragmentation pathways of protonated piperine and its metabolites. In total, four stable metabolites and their isomers (M1a‐c, M2a‐b, M3a‐c, and M4a‐b) were detected. Their formation involved removal of carbon (3, M1a‐c), hydroxylation (2, M2a‐b), hydroxylation with hydrogenation (3, M3a‐c), and dehydrogenation (2, M4a‐b). Out of these metabolites, M1, M2, and M3 are reported earlier in the literature, but their isomers and two M4 variants are novel. In addition, six novel conjugates of RMs, including three GSH conjugates of m/z 579 and three NAC conjugates of m/z 435, were also observed. 相似文献
954.
Virendra Patil Woong Oh Jong Won Yoo Lyongsun Pu Jong Hyeok Park Won‐Sub Yoon Gi‐Ra Yi 《Particle & Particle Systems Characterization》2019,36(7)
One of the key strategies used to obtain high‐rate Li‐ion battery is the reduction of the Li‐ion path length inside the active materials and the enhancement of the ionic diffusion outside the active materials. It is demonstrated that electrochemical performance can be improved significantly at high C‐rates using carbon‐coated spherical aggregates or “supraballs” of randomly packed olivine LiFePO4 (LFP) nanoplates as cathode active materials. 258 nm LFP nanoplates with 30 nm thickness are synthesized through a high‐temperature solvothermal method, in which short lithium‐ion channels are formed perpendicular to the top or bottom planes. These thin nanoplates are formed into carbon‐coated “supraballs” through a spray‐drying and thermal annealing process, in which nanoplates are not stacked but randomly packed due to relatively fast drying. Internal and external nanoplate ion diffusion is therefore enhanced simultaneously due to the optimal molecular crystalline structure and interparticle pore structures of the nanoplates. Indeed, the initial capacity of the carbon‐coated supraballs is 162 mAh g?1 (173.34 mAh cm?3) at 0.1 C and more than 80% is retained (≈130.91 mAh g?1) at 50 C. Furthermore, they offer durable cycling stability (>500 cycles) at 1 C without compromising their capacity. 相似文献
955.
Satish Gudala Srinivasa Rao Ambati Jeevan Lal Patel Rajeswar Rao Vedula Santhosh Penta 《Journal of heterocyclic chemistry》2019,56(8):2163-2169
An efficient synthetic strategy has been developed for the synthesis of pyrazolyl‐1,2,3‐thiadiazoles via Hurd–Mori cyclization reaction. The reaction of various pyrazolyl‐phenylethanones with semicarbazide hydrochloride in the presence of sodium acetate/methanol gave the corresponding semicarbazones ( 3a – i ). These semicarbazones were further reacted with thionyl chloride via the Hurd–Mori cyclization conditions to accomplish the title products ( 4a – i ). The present protocol favored for the formation of both pyrazolyl semicarbazone derivatives and pyrazolyl‐1,2,3‐thiadiazole derivatives by forming C─S, N─S, and C═N bonds in excellent yields with variety of substrates. The final compounds were characterized by analytical and spectral studies. 相似文献
956.
This paper reports the optical transmission loss of tin oxide thin film waveguide. The effect of oxidation temperature, thickness and air ageing (40 days at room temperature) was studied. The vapour chopping technique has been used successfully to reduce the optical transmission loss. The vapour chopped tin oxide thin film waveguide (2.90-3.60 dB/cm) showed smaller transmission loss than those of nonchopped tin oxide thin film waveguide (4.16-4.74 dB/cm). Transmission loss was found to be a function of oxidation temperature and thickness. Due to increased oxidation temperature, transmission loss was found to decrease. The effect of increase in thickness was to increase the transmission loss. The air ageing effect caused the increase in transmission loss whereas the effect was found lesser in the vapour chopped tin oxide thin film waveguide. 相似文献
957.
We consider a gauge symmetric version of the p-spin glass model on a complete graph. The gauge symmetry guarantees the absence of replica symmetry breaking and allows to
fully use the interpolation scheme of Guerra (Fields Inst. Commun. 30:161, 2001) to rigorously compute the free energy. In the case of pairwise interactions (p=2), where we have a gauge symmetric version of the Sherrington-Kirkpatrick model, we get the free energy and magnetization
for all values of external parameters. Our analysis also works for even p≥4 except in a range of parameters surrounding the phase transition line, and for odd p≥3 in a more restricted region. We also obtain concentration estimates for the magnetization and overlap parameter that play
a crucial role in the proofs for odd p and justify the absence of replica symmetry breaking. Our initial motivation for considering this model came from problems
related to communication over a noisy channel, and is briefly explained. 相似文献
958.
S.D. Patil S.T. Navare M.V. Takale M.B. Dongare 《Optics and Lasers in Engineering》2009,47(5):604-606
The authors have investigated self-focusing of cosh-Gaussian laser beams in a parabolic medium with linear absorption. The field distribution in the medium is expressed in terms of beam-width parameter f, decentred parameter b and absorption coefficient ki. The differential equation for f parameter is established by following Wentzel–Kramers–Brillouin (WKB) and paraxial approximations through parabolic wave equation approach and analytical solution is obtained for the same. The behavior of f parameter with the normalized distance of propagation η is studied at various values of b with different absorption levels in the medium. The results are presented graphically and discussed. 相似文献
959.
Mohan S Lockwood ME Kramer ML Jones DL 《The Journal of the Acoustical Society of America》2008,123(4):2136-2147
Direction finding of more sources than sensors is appealing in situations with small sensor arrays. Potential applications include surveillance, teleconferencing, and auditory scene analysis for hearing aids. A new technique for time-frequency-sparse sources, such as speech and vehicle sounds, uses a coherence test to identify low-rank time-frequency bins. These low-rank bins are processed in one of two ways: (1) narrowband spatial spectrum estimation at each bin followed by summation of directional spectra across time and frequency or (2) clustering low-rank covariance matrices, averaging covariance matrices within clusters, and narrowband spatial spectrum estimation of each cluster. Experimental results with omnidirectional microphones and colocated directional microphones demonstrate the algorithm's ability to localize 3-5 simultaneous speech sources over 4 s with 2-3 microphones to less than 1 degree of error, and the ability to localize simultaneously two moving military vehicles and small arms gunfire. 相似文献
960.
Satish D. Joglekar 《International Journal of Theoretical Physics》2008,47(11):2824-2834
We study the question of whether a composite structure of elementary particles, with a length scale 1/Λ, can leave observable
effects of non-locality and causality violation at higher energies (but ≲Λ). We formulate a model-independent approach based
on Bogoliubov-Shirkov formulation of causality. We analyze the relation between the fundamental theory (of finer constituents)
and the derived theory (of composite particles). We assume that the fundamental theory is causal and formulate a condition
which must be fulfilled for the derived theory to be causal. We analyze the condition and exhibit possibilities which fulfil
and which violate the condition. We make comments on how causality violating amplitudes can arise. 相似文献