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41.
Journal of Materials Science: Materials in Electronics - Pure V2O5 and MnO2/V2O5 hybrid nanocomposites were synthesized by microwave-assisted method for electrochemical supercapacitor application....  相似文献   
42.
Chromium was deposited on steel substrates using direct current pulsed high frequency and pulsed low frequency plating methods. The samples obtained from the different plating techniques were later exposed to a corrosive NaCl solution. The time of exposure was varied, for 0, 80 and 140 hours and later the samples were subjected to impedance measurements. In the present study an attempt has been made to characterise the best plating method using impedance data analysis.  相似文献   
43.
The EM analysis of multi-layered metamaterial based radar absorbing structure (RAS) with dual-band characteristics in millimeter wave frequency regime has been carried out in this paper using transmission line transfer matrix (TLTM) method for TE and TM polarizations. The proposed metamaterial-based RAS exhibits dual-band characteristics at centre frequencies 120 GHz and 175 GHz with very low power reflection. It absorbs more than 90% power of incidence wave over the frequency range from 111-131 GHz at first resonance and from 164.5-185 GHz at second resonance without metal backing plate, which is desirable for stealth applications. It also showed very low (< 1.6%) transmission over the frequency of interest for both TE and TM polarizations. The proposed metamaterial-RAS has potential applications in the design of multi-band sensor systems and RCS reduction in millimeter wave frequency regime.  相似文献   
44.
45.
Chemical oxidative polymerization of aniline (ANI) and o/m-toluidine (OT or MT) and their nano composites at different experimental conditions were performed using peroxydisulfate (PDS) as a lone chemical initiator and V2O5 as a host material in an aqueous HCl medium at 45 °C under nitrogen atmosphere. The nano composites were synthesized under different experimental conditions and were characterized by Fourier transform infra red (FTIR) spectroscopy, conductivity measurements, high resolution transmission electron microscopy (HRTEM) and thermogravimetric analysis (TGA) like analytical tools. The effect of methyl substituent in the phenyl ring of ANI derivatives on the structure and property relationship of copolymer was studied.  相似文献   
46.
The interaction and crosstalk of Toll-like receptors (TLRs) is an established pathway in which the innate immune system recognises and fights pathogens. In a single nucleotide polymorphisms (SNP) analysis of an Indian cohort, we found evidence for both TLR4-399T and TRL8-1A conveying increased susceptibility towards tuberculosis (TB) in an interdependent manner, even though there is no established TLR4 ligand present in Mycobacterium tuberculosis (Mtb), which is the causative pathogen of TB. Docking studies revealed that TLR4 and TLR8 can build a heterodimer, allowing interaction with TLR8 ligands. The conformational change of TLR4-399T might impair this interaction. With immunoprecipitation and mass spectrometry, we precipitated TLR4 with TLR8-targeted antibodies, indicating heterodimerisation. Confocal microscopy confirmed a high co-localisation frequency of TLR4 and TLR8 that further increased upon TLR8 stimulation. The heterodimerisation of TLR4 and TLR8 led to an induction of IL12p40, NF-κB, and IRF3. TLR4-399T in interaction with TLR8 induced an increased NF-κB response as compared to TLR4-399C, which was potentially caused by an alteration of subsequent immunological pathways involving type I IFNs. In summary, we present evidence that the heterodimerisation of TLR4 and TLR8 at the endosome is involved in Mtb recognition via TLR8 ligands, such as microbial RNA, which induces a Th1 response. These findings may lead to novel targets for therapeutic interventions and vaccine development regarding TB.  相似文献   
47.
Latha Ramakrishnan 《Polymer》2005,46(15):5506-5513
Free radical bulk polymerization of styrene and methyl methacrylate (MMA) was carried out using a novel ‘macroiniferter’ which resulted in branched polymers with relatively narrow molecular weight distribution. This approach involving the novel macroiniferter; poly[3-(t-butylperoxy)propyl disulfide] (PBPPDS) that has side chain peroxide groups and main chain disulfide linkages was developed to prepare soluble branched polymers as well as to control the extent of branching in vinyl polymers synthesized via a free radical route. The synthesis, characterization and thermal degradation studies of PBPPDS are reported here for the first time. The resulting polystyrene (PS) and poly(methyl methacrylate) (PMMA) polymers were characterized using gel permeation chromatography (GPC), intrinsic viscosity [η] measurements and the degree of branching was studied by the determination of g′ factor.  相似文献   
48.

Background  

Although soy protein and its isoflavones have been reported to reduce the risk of osteoporosis in peri- and post-menopausal women, most of these studies are of short duration (i.e. six months). The objective of this study was to examine if one year consumption of soy-containing foods (providing 25 g protein and 60 mg isoflavones) exerts beneficial effects on bone in postmenopausal women.  相似文献   
49.
Studies of 2-D atomic hydrogen at high densities on helium surfaces have been plagued by the heating of the surfaces due to recombination, which dissipates more than 52, 000K for each recombining pair of atoms in the cell. When hydrogen recombines on a surface, it deposits less than 4% of its energy at the point of recombination and the rest is carried off by the excited molecule. We have designed a maze to absorb most of this energy, and carried out a Monte Carlo simulation to show that approximately 87% of the energy is dissipated in the maze, preventing the surface from getting excessively heated, even at high surface densities. This simulation varies the number of inelastic collisions with the maze wall for complete relaxation, the fraction of elastic collisions, and the angular distribution of excited molecules desorbing from the walls.  相似文献   
50.
Denatured lysozyme was refolded by a dilution method. The refolding yield depended greatly on the lysozyme concentration in the refolding mixture. When the concentration of denatured lysozyme was 0.02 g/L, the refolding yield was as high as 60%. However, when the concentration of denatured lysozyme was 0.2 g/L, the refolding yield was as low as 10% due to the formation of aggregates. To prevent the formation of aggregates and to increase the refolding yield at a low cost, inexpensive additives were screened. The addition of acetone, acetoamide, or urea derivatives was very effective for improving the refolding yield. To clarify why the addition of acetoamide in the refolding mixture improved the refolding yield at the high lysozyme concentration, the time courses of the concentration and the average diameter of the aggregates in the refolding mixture were monitored by the dynamic light scattering method. The experimental results showed that acetoamide played a role in preventing the formation and growth of aggregates and secondary aggregation between the lysozyme aggregates.  相似文献   
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