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1.
Wireless Personal Communications - Data security is currently become a serious concern in wireless communication system for both the users and providers. Without a secure medium, the data...  相似文献   
2.
Knowledge of the information goal of users is critical in website design, analyzing the efficacy of such designs, and in ensuring effective user-access to desired information. Determining the information goal is complex due to the subjective and latent nature of user information needs. This challenge is further exacerbated in media-rich websites since the semantics of media-based information is context-based and emergent. A critical step in determining information goals lies in the identification of content pages. These are the pages which contain the information the user seeks. We propose a method to automatically determine the content pages by taking into account the organization of the web site, the media-based information content, as well as the influence of a specific user browsing pattern. Given a specific browsing pattern, in our method, putative content pages are identified as the pages corresponding to the local minima of page-content entropy values. For an (unknown) user information goal this intuitively corresponds to modeling the progressive transition of the user from pages with generic information to those with specific information. Experimental investigations on media rich sites demonstrate the effectiveness of the technique and underline its potential in modeling user information needs and actions in a media-rich web.  相似文献   
3.
At present, the potential role of the AgNPs/endo-fullerene molecule metal nano-composite has been evaluated over the biosystems in-vitro. The intra-atomic configuration of the fullerene molecule (C60) has been studied in-vitro for the anti-proliferative activity of human breast adenocarcinoma (MDA-MB-231) cell lines and antimicrobial activity against a few human pathogens that have been augmented with the pristine surface plasmonic electrons and antibiotic activity of AgNPs. Furthermore, FTIR revealed the basic vibrational signatures at ~3300 cm−1, 1023 cm−1, 1400 cm−1 for O-H, C-O, and C-H groups, respectively, for the carbon and oxygen atoms of the C60 molecule. NMR studies exhibited the different footprints and magnetic moments at ~7.285 ppm, explaining the unique underlying electrochemical attributes of the fullerene molecule. Such unique electronic and physico-chemical properties of the caged carbon structure raise hope for applications into the drug delivery domain. The in-vitro dose-dependent application of C60 elicits a toxic response against both the breast adenocarcinoma cell lines and pathogenic microbes. That enables the use of AgNPs decorated C60 endo fullerene molecules to design an effective anti-cancerous drug delivery and antimicrobial agent in the future, bringing a revolutionary change in the perspective of a treatment regime.  相似文献   
4.
In the present study, green synthesis and cost effective approach of silver nanoparticles using wild medicinal mushroom Ganoderma applanatum (Pers.) Pat. from Similipal Biosphere Reserve, Odisha, India is reported. The biosynthesised AgNPs were characterised using UV‐visible spectroscopy, particle analyser and scanning electron microscopy studies. It was found by dynamic light scattering analysis, that the average size and charges of the AgNPs were 133.0 ± 0.361 nm and −6.01 ± 5.30 mV, respectively. Moreover, the Fourier transform infrared study was also conducted to identify the biomolecules or functional groups responsible for the reduction of Ag and stabilisation of the AgNPs. The potential biomedical application with reference to antimicrobial activity of the synthesised AgNPs was investigated against some pathogenic microorganisms viz. Escherichia coli, Bacillus subtilis, Staphylococcus epidermidis, Vibrio cholerae, Staphylococcus aureus and Shigella flexneri.Inspec keywords: antibacterial activity, biomedical materials, nanomedicine, nanofabrication, materials preparation, ultraviolet spectra, visible spectra, scanning electron microscopy, Fourier transform infrared spectra, molecular biophysics, reduction (chemical), biochemistry, microorganisms, silver, nanoparticlesOther keywords: green synthesis, antimicrobial activity, silver nanoparticles, wild medicinal mushroom, Ganoderma applanatum Pat, Similipal Biosphere Reserve, Odisha, UV‐visible spectroscopy, particle analyser, scanning electron microscopy, dynamic light scattering analysis, Fourier transform infrared study, biomolecules, functional groups, silver reduction, AgNP stabilisation, biomedical application, pathogenic microorganisms, Escherichia coli, Bacillus subtilis, Staphylococcus epidermidis, Vibrio cholerae, Staphylococcus aureus, Shigella flexneri, Ag

Abbreviations

AgNPs
‐ Silver Nanoparticles
SPR
‐Surface plasmon resonance
AgNO3
‐Silver nitrate
nm
‐ Nanometer
mm
‐Milimetre
  相似文献   
5.
分析用布袋除尘器处理高温烟气的系统中影响野风阀降温的因素,指出其作用的局限性。  相似文献   
6.
Active Fiber Bragg Grating Hydrogen Sensors for All-Temperature Operation   总被引:1,自引:0,他引:1  
The use of liquid hydrogen as a fuel requires low-cost multipoint sensing of hydrogen gas for leak detection and location well below the 4% explosion limit of hydrogen. Herein is presented a multipoint in-fiber hydrogen sensor capable of hydrogen detection below 0.5% concentration with a response time of less than 10 s. Our solution entails use of a fiber Bragg grating (FBG) coated with a layer of hydrogen-absorbing palladium which, in turn, induces strain in the FBG in the presence of hydrogen. Infrared power laser light is used to induce heating in the palladium coating which dramatically decreases sensor response time and increases the sensor's sensitivity at low temperatures. This technology promises an inexpensive fiber solution for a multipoint hydrogen detection array with only one fiber feed-through  相似文献   
7.
Precise measurements on the electrical conductivity of solutions of sodium polystyrenesulphonate in methanol–water mixed solvent media containing 8, 16, 25, and 34 wt.% of methanol at 308.15, 313.15, 318.15, and 323.15 K are reported. The degree of substitution of sodium polystyrenesulphonate used was 1, and the concentrations were varied from ∼2.0 × 10−4 to ∼4.0 × 10−3 monomol l−1. The results showed a slight and monotonous increase in the equivalent conductivity with decreasing polyelectrolyte concentration. The applicability of the Manning’s theory for salt-free polyelectrolyte solution was examined and a major discrepancy against the theory was observed. The calculated values of the equivalent conductivity deduced on the basis of this theory were found to be lower than the experimental ones. Possible reasons for this discrepancy have been discussed. The effects of the temperature and relative permittivity of the medium on the equivalent conductivity were also investigated. Estimation of the fractions of uncondensed counterions provides important insight regarding the solution behavior of the polyelectrolyte in methanol–water mixtures.  相似文献   
8.

Background  

Dietary assessment tools are often too long, difficult to quantify, expensive to process, and largely used for research purposes. A rapid and accurate assessment of dietary fat intake is critically important in clinical decision-making regarding dietary advice for coronary risk reduction. We assessed the validity of the MEDFICTS (MF) questionnaire, a brief instrument developed to assess fat intake according to the American Heart Association (AHA) dietary "steps".  相似文献   
9.
This work focuses on estimation of global solar radiation and, in particular, it explores the effect of precipitation and temperature on solar radiation profile of Kathmandu (Nepal). An accurate knowledge of solar radiation distribution in each particular geographical location is crucial for the promotion of solar energy technology. The best way of knowing the amount of global solar radiation is to install quality instruments at many locations in the given region. This requires their day to day maintenance, recording and calibration, which is very costly in developing countries like Nepal. Thus, the alternative approach is to correlate meteorological measurements with appropriate models and investigate the key parameters. For the research activities the RadEst program has been used. It includes, for evaluating the daily global solar radiation values at a given latitudes, four models which estimate the atmospheric transmissivity by measurements of daily temperature range and precipitations. The model parameters are fitted in 2 years data by iterative procedures. The values obtained by these models are, then, compared with measured radiation data. The paper reports graphical and statistical evaluations suggesting that among the four models, the Modular DCBB is the best model for Kathmandu area. This result is useful for designing solar panels able to maximize the harvesting of solar energy and to reduce the chronic shortage of hydrocarbon fuel that Nepal imports in a significant amount each year.  相似文献   
10.
Computer modeling of liquid phase poses tremendous challenge: It requires a relatively large simulation size, long simulation time and accurate interatomic interaction and as such, it produces massive amounts of data. Recent advances in hardware and software have made it possible to accurately simulate the liquid phase. This paper reports the details of methodology used in the context of liquid simulations and subsequent analysis of the output data. For illustration purpose, we consider the results for the liquid phases of two geophysically relevant materials, namely MgO and MgSiO3. The simulations are performed using the parallel first-principles molecular dynamics (FPMD) technique within the framework of density functional theory. Various physical properties including the equation of state, diffusion, atomic structure and electronic structure of these liquids are obtained as a function of pressure and temperature. The three-dimensional and timedependent data for atomic configuration and electronic density are analyzed using the recently developed spacetime- multiresolution and multiple-dataset-visualization techniques. It is shown that the structural, dynamical and electronic properties of the liquid phases are highly sensitive to compression, with no discernible influence of temperature in most cases.  相似文献   
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