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71.
Nutan Shukla Baljinder Singh Ho-Joong Kim Myoung-Hwan Park Kibeom Kim 《Particle & Particle Systems Characterization》2020,37(8):2000099
Multimodal approaches combined with various nanomaterials and advanced techniques have been developed for synergistic cancer treatment. Among various therapies, conventional chemotherapy (CHT) is a direct cancer treatment that can produce unintended side effects due to nonspecific action on both the tumor and normal cells; patient-friendly photothermal therapy (PTT) may be able to treat embedded tumors in vital regions with minimal invasion but does not guarantee complete removal of cancers. However, the combination of CHT-PTT may provide a promising tool for direct cancer treatment with minimal side effects. In this regard, nanostructured materials, such as gold nanorods with tuned size and surface characteristics, are key components designed to enhance the heating capacity and active or passive delivery of drugs to the tumor site. In this review, the pioneering work synergizing CHT and PTT is summarized, and the current state-of-the-art in the development of inorganic and organic nanocomposites for combinational therapy is described. 相似文献
72.
Vanadium redox flow battery (VRFB) is a promising technology for large-scale renewable energy storage. Design of ion-exchange membrane (IEM) with desired properties like low-cost, mechanically chemically stable, low vanadium ion permeability and high proton conductivity is one of the major challenges. Here, we report the design and synthesis of novel poly(tetrafluoroethylene)-zirconium phosphate (PTFE-ZrP) asymmetric IEM using a simple brush coating method. XRD results confirmed the presence of α-ZrP crystalline phase onto the top layer of the membrane. Excellent mechanical strength was observed with burst pressure of 3.22 × 105 N m?2. Oxidative stability of membrane in Fenton’s reagent was much better than Nafion-115. Vanadium ion (V4+) permeability of the membrane was more than three times lower than that of Nafion-115. Single-cell VRFB with PTFE-ZrP membrane showed ~80% energy efficiency below 30 mA cm?2. Very high columbic efficiency ~100% of VRFB with PTFE-ZrP membrane confirmed little contamination of electrolyte due to cross-mixing. 相似文献
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In this paper we study spectral sets which are unions of finitely many intervals in R. We show that any spectrum associated with such a spectral set Ω is periodic, with the period an integral multiple of the measure of Ω. As a consequence we get a structure theorem for such spectral sets and observe that the generic case is that of the equal interval case. 相似文献
76.
R. Khare P.K. Shukla G.K. Mishra C. Mukherjee S. Talwar V.K. Dubey P. Saxena J.K. Mittal 《Optics Communications》2009,282(19):3850-3853
We present an analytical and experimental study of a novel confocal optical pulse stretcher (COPS). The simple and passive pulse stretcher consists of two concave mirrors and a scraper beam-splitter and its optical configuration ensures a perfect spatial overlapping of laser pulses at the beam-splitter. The pulse stretcher is compact and suitable for laser pulses of large divergences. The confocal optical pulse stretcher is demonstrated on a pulsed copper vapour laser to convert a 40 ns (1/e2 % points) pulse into a 55 ns with reduction of peak power by a factor of 1.375 without loss of pulse energy. 相似文献
77.
N-Cinnamoyl-L-proline can be used as a template on which beta-substituted phenylalanine and beta-phenylisoserine residues can be synthesized leading to tripeptide derivatives as structural analogues of HIV protease inhibitors. 相似文献
78.
d'Astuto M Mang PK Giura P Shukla A Ghigna P Mirone A Braden M Greven M Krisch M Sette F 《Physical review letters》2002,88(16):167002
The phonon dispersions of Nd(1.86)Ce(0.14)CuO(4+delta) along the [xi,0,0] direction have been determined by inelastic x-ray scattering. Compared to the undoped parent compound, the two highest longitudinal phonon branches, associated with the Cu-O bond stretching and out-of-plane oxygen vibration, are shifted to lower energies. Moreover, an anomalous softening of the bond-stretching band is observed at about q = (0.2,0,0). These signatures provide evidence for strong electron-phonon coupling in this electron-doped high-temperature superconductor. 相似文献
79.
Dallera C Grioni M Shukla A Vankó G Sarrao JL Rueff JP Cox DL 《Physical review letters》2002,88(19):196403
Resonant inelastic x-ray scattering (RIXS) yields clear evidence of spectroscopic Kondo scales in heavy fermions. In YbInCu4 and YbAgCu4 RIXS probes the Yb2+ component of the hybrid ground state and the temperature dependence of the Yb 4f occupation. We report a sudden valence change at a phase transition in YbInCu4, but a continuous temperature dependence in YbAgCu4, consistent with the predictions of the Anderson impurity model, for a Kondo temperature T(K) = 70 K. These results solve a long-standing controversy and establish RIXS as a quantitative probe of the electronic structure of strongly correlated electron systems. 相似文献
80.
The present paper considers the magnifying power and aberration properties of three different catadioptric magnifying systems
useful for application as simple hand-held microfiche readers. These are in the form of a plano-convex lens, a meniscus lens
and an achromatic doublet lens and all their outer surfaces have been coated with a semi-reflecting film so that they behave
like catadioptric elements. These can be designed to give magnification in the range of 15 × to 25 × with sufficient eye relief.
Using such magnifiers, it is possible to read microfiche having frame sizes of 16 × 12 mm and 12 × 9 mm. The cemented achromatic
doublet coated on the outer surfaces seems to give a very good image for use in microfiche reader. 相似文献