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排序方式: 共有226条查询结果,搜索用时 15 毫秒
21.
22.
Lu L Wohlfart A Parala H Birkner A Fischer RA 《Chemical communications (Cambridge, England)》2003,(1):40-41
Room-temperature preparation of nano-Cu on ZnO by UV light induced photo-reduction of Cu(OCH(Me)CH2NMe2)2 precursor was achieved, indicating a novel method of nano-Cu/ZnO synthesis from an organometallic copper precursor in non-aqueous media without further chemical reduction. 相似文献
23.
Vikas N. Telvekar Kavit N. Patel Harish S. Kundaikar Hemchandra K. Chaudhari 《Tetrahedron letters》2008,49(14):2213-2215
A simple and mild method for the conversion of varieties of aldehydes to the corresponding nitriles using aqueous ammonia and aqueous sodium dichloroiodate reagent at room temperature is discussed. Advantages of this system are short reaction time, easy work-up and moderate to good yields. 相似文献
24.
Vivekanandan Kannan Pradeep Narayanaswamy Deepak Gadamsetty Partha Hazra Anand Khedkar Harish Iyer 《Rapid communications in mass spectrometry : RCM》2009,23(7):1035-1042
Glycoforms of glargine expressed in Pichia pastoris were isolated by high‐performance liquid chromatography and analyzed by a series of chemical and mass spectrometric methods for the identification of various glycoforms, glycosylation position, nature and structure of glycans. Reduction and alkylation, peptide mapping techniques were used to decipher the amino acid site at which glycosylation had taken place. Chemical methods were coupled with mass spectrometry techniques such as electrospray ionization and matrix‐assisted laser desorption/ionization for identification of the glycosylation site. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
25.
Fisetin Inhibits UVB‐induced Cutaneous Inflammation and Activation of PI3K/AKT/NFκB Signaling Pathways in SKH‐1 Hairless Mice
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Harish Chandra Pal Mohammad Athar Craig A. Elmets Farrukh Afaq 《Photochemistry and photobiology》2015,91(1):225-234
Solar ultraviolet B (UVB) radiation has been shown to induce inflammation, DNA damage, p53 mutations and alterations in signaling pathways eventually leading to skin cancer. In this study, we investigated whether fisetin reduces inflammatory responses and modulates PI3K/AKT/NFκB cell survival signaling pathways in UVB‐exposed SKH‐1 hairless mouse skin. Mice were exposed to 180 mJ cm?2 of UVB radiation on alternate days for a total of seven exposures, and fisetin (250 and 500 nmol) was applied topically after 15 min of each UVB exposure. Fisetin treatment to UVB‐exposed mice resulted in decreased hyperplasia and reduced infiltration of inflammatory cells. Fisetin treatment also reduced inflammatory mediators such as COX‐2, PGE2 as well as its receptors (EP1–EP4) and MPO activity. Furthermore, fisetin reduced the level of inflammatory cytokines TNFα, IL‐1β and IL‐6 in UVB‐exposed skin. Fisetin treatment also reduced cell proliferation markers as well as DNA damage as evidenced by increased expression of p53 and p21 proteins. Further studies revealed that fisetin inhibited UVB‐induced expression of PI3K, phosphorylation of AKT and activation of the NFκB signaling pathway in mouse skin. Overall, these data suggest that fisetin may be useful against UVB‐induced cutaneous inflammation and DNA damage. 相似文献
26.
Laser material processing, being a non-contact process, minimizes many of the complexities involved in the decontamination and decommissioning of nuclear facilities. A high power laser beam incident on a concrete surface can produce spalling, glazing or vaporization, depending upon the laser power density and scan speed. This paper presents effect of various laser processing parameters on the efficiency of material removal by surface spalling and glazing. The size of laser beam at constant fluence or energy density had significantly different effect on the spalling process. In thick concrete block cutting the flow or removal of molten material limits the cutting depth. By employing repeated laser glazing followed by mechanical scrubbing process cutting of 150 mm thick concrete block was carried out. Gravitation force was utilized for molten materials to flow out while drilling holes on vertical concrete walls. The dependence of the incident laser beam angle on drilling time was experimentally studied. 相似文献
27.
Pratul Bandyopadhyay Brahmananda Bhattacharya Harish Sarkar 《International Journal of Theoretical Physics》1983,22(8):677-689
In quantum neutrinodynamics (photon-neutrino weak coupling) all the renormalization constants vanish and therefore the field equations cannot be expressed in terms of unrenormalized field quantities. This helps us to formulate quantum neutrinodynamics as a convergent quantum field theory. It is also pointed out that from the viewpoint of the unified model of weak and electromagnetic interaction as developed on the basis of the photon-neutrino weak coupling by Bandyopadhyay, quantum electrodynamics also manifests itself as a convergent field theory. 相似文献
28.
The electroproduction of low energy pions is calculated for experimental situations corresponding to the detection of only one of the outgoing particles. The final nuclear state is a superposition of particle-hole states, corresponding to the giant resonances. A comparison with the predictions of the Fermi gas model is made. The effect of final state interactions was included by using a distorted wave impulse approximation to describe electroproduction from nuclei. Distortion effects near threshold have a significant effect on the magnitude of the electroproduction cross section. 相似文献
29.
P. Chowdhury Harish C. Barshilia P.K. Mishra D.V. Sridhara Rao 《Journal of magnetism and magnetic materials》2010,322(21):3266-3270
To study the influence of oxygen impurities in the sputtering atmosphere on microstructure, and the magnetic and magnetotransport properties, thin films of Ni83Fe17 were deposited under dc magnetron sputtering technique into which regulated oxygen gas was introduced. The partial pressure of oxygen was varied from 2×10−7 to 3×10−6 mbar. X-ray diffraction patterns indicate the reduction of grain growth with increasing the oxygen partial pressure. The grain microstructure and the composition were confirmed through high resolution transmission electron microscopy attached with Scanning Transmission Electron Microscopy (STEM). Transition from canted to rectangular magnetic hysteresis loop was observed through magnetization measurements for samples prepared under higher oxygen partial pressure which implies the structural changes in the magnetic domain formation. These observations were further confirmed through the measurements of anisotropic magnetoresistance properties. 相似文献
30.
Boris Baeumer Mihály Kovács Harish Sankaranarayanan 《Journal of Differential Equations》2018,264(2):1377-1410
We identify the stochastic processes associated with one-sided fractional partial differential equations on a bounded domain with various boundary conditions. This is essential for modelling using spatial fractional derivatives. We show well-posedness of the associated Cauchy problems in and . In order to do so we develop a new method of embedding finite state Markov processes into Feller processes on bounded domains and then show convergence of the respective Feller processes. This also gives a numerical approximation of the solution. The proof of well-posedness closes a gap in many numerical algorithm articles approximating solutions to fractional differential equations that use the Lax–Richtmyer Equivalence Theorem to prove convergence without checking well-posedness. 相似文献