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241.
Wireless Personal Communications - Disaster or emergency can create unusual circumstances. And usually they are extremely hard to stop. However, an intelligent approach or strategy can limit the...  相似文献   
242.
ZW3 is a newly discovered exopolysaccharide (EPS) produced by Lactobacillus kefiranofaciens ZW3, isolated from Tibet kefir. Some of its properties have been characterized in our previous paper. Present research demonstrates some other important aspects of this EPS. The molecular weight obtained by gel permeation HPLC was 5.5 × 104 Da. Solubility, water holding and oil binding capacity of ZW3 EPS were 14.2%, 496.0%, and 884.74% respectively. Scanning electron microscopy (SEM) of ZW3 EPS demonstrated a smooth surface with compact structures. A topographical examination of EPS by atomic force microscopy (AFM) revealed that ZW3 EPS is composed of almost uniform net of molecules. Rheological study indicated that common salt did not affect the viscous behavior of ZW3 EPS and acidic pH may enhance its viscosity. Exopolymer showed a melting point of 93.38 °C. A degradation temperature (Td) of 299.62 °C was observed from the TGA curve for the polysaccharide ZW3.  相似文献   
243.
Lysozyme is a commercially valuable enzyme, and is applied in many fields, concerning products such as foods, drugs, and the like. In this work, lysozyme was isolated and purified from buffalo milk using sephadex G-50 and cation exchanger carboxymethyl cellulose. Lysozyme active fractions from buffalo milk were assayed against Gram positive substrate Micrococcus luteus at 450 nm and a decline in absorbance of 0.001 per min was observed. The optimum activity of lysozyme (158.3 ± 1.7 units/mL) was at 7.5 pH and 37°C temperature. Lysozyme activity at pasteurization temperatures 62.5°C, 30 min and 75°C, 15 s were (156.08 ± 1.03 and 156 ± 2 units/mL) not affected significantly; however, 47% activity of lysozyme was reduced at 100°C for 5 min. Antibacterial susceptibility testing of lysozyme (chicken egg white lysozyme and buffalo milk lysozyme) was performed on Micrococcus luteus (ATCC 4698) and Escherichia coli (ATCC 25235). Both lysozymes showed no inhibition effect against Escherichia coli.  相似文献   
244.
ABSTRACT

Glycerol plasticised soy protein isolate (SPI) films at different contents (1 to 5% w/w w.r.t SPI) of zinc sulphide (ZnS) nanoparticles were fabricated. Before the film formation, the ZnS nanoparticles incorporated SPI suspensions were subjected to molecular mass studies by SDS-PAGE and specific conductivity studies. SPI films and ZnS nanoparticles incorporated SPI films were structurally and mechanically characterised by Fourier transform infrared spectroscopy (FT-IR) and mechanical properties, respectively. Transmittance and water uptake studies were also carried out for ZnS nanoparticles incorporated SPI films. The results from transmittance, water uptake and FT-IR studies indicated a good compatibility between the ZnS nanoparticles and the SPI. With the increase in the contents of ZnS nanoparticles from 0 to 4%, the tensile modulus increased from 87.4 to 99?MPa. The water uptake decreased significantly from 159 to 10.76%. However, the results showed the absence of antibacterial effect in ZnS nanoparticles incorporated SPI film.  相似文献   
245.
Abstract

The last 15?years has witnessed a surge in rail-related human factors research but little has examined the Track Worker role. Track work often takes place whilst trains are running under the protection of Lookouts who provide warning of approaching trains. Despite—or perhaps because of—these measures, there is a notable prevalence of incidents involving Lookouts, warranting a closer look at the nature of their task and the wider sociotechnical system (STS) to identify what may be learned for railway safety management. A systematic review of incident reports involving Lookouts was undertaken on Australian and UK rail incidents from 2006 to mid-2018 with a qualitative meta-analysis (n?=?31) revealing nine factors corresponding with STS dimensions at the organisational, social, task and individual level. Much of the risk lay in the set up and implementation of Lookout working, and in Track Worker group dynamics—factors endemic to working whilst trains are running—rather than specific to the Lookout, with such factors arguably applicable across other Track Worker groups. Findings point to a need for more targeted research into the STS aspects of track working, as well as improving the training and/or procedures of those managing the Lookout protection system of work.  相似文献   
246.
A signal passed at danger (SPAD) event occurs when a train moves past a stop signal into a section of unauthorised track. SPAD events are frequently attributed to driver distraction and inattention, but few studies have explored the failure mode from the perspective of task demand and the ability of the driver to self-regulate in response to competing activities. This study aimed to provide a more informed understanding of distraction, inattention and SPAD-risk in the passenger rail task. The research approach combined focus groups with a generative task designed to stimulate situational insight. Twenty-eight train drivers participated from 8 different rail operators in Australia and New Zealand. Data were analysed thematically and revealed several moderating factors for driver distraction. Time-keeping pressure and certain aspects of the driver-controller dynamic were considered to distort performance, and distractions from station dwelling and novel events increased SPAD-risk. The results are conceptualised in a succinct model of distraction linking multiple factors with mechanisms that induced the attentional shift. The commonalities and inter-dynamics of the factors revealed insight into driving anxiety in the passenger rail mode, and suggested that SPAD-risk was intensified when three or more factors converged. The paper discusses these issues in the context of misappropriated attention, taxonomic implications, and directions for future research.  相似文献   
247.
Landfill leachate (LFL) treatment is a severe challenge due to its highly viscous nature and various complex pollutants. Leachate comprises various toxic pollutants, including inorganic macro/nano components, xenobiotics, dissolved organic matter, heavy metals, and microorganisms responsible for severe environmental pollution. Various treatment procedures are available to achieve better effluent quality levels; however, most of these treatments are nondestructive, so pollutants are merely transported from one phase to another, resulting in secondary contamination. Anaerobic digestion is a promising bioconversion technology for treating leachate while producing renewable, cleaner energy. Because of its high toxicity and low biodegradability, biological approaches necessitate employing other techniques to complement and support the primary process. In this regard, pretreatment technologies have recently attracted researchers’ interest in addressing leachate treatment concerns through anaerobic digestion. This review summarizes various LFL pretreatment methods, such as electrochemical, ultrasonic, alkaline, coagulation, nanofiltration, air stripping, adsorption, and photocatalysis, before the anaerobic digestion of leachate. The pretreatment could assist in converting biogas (carbon dioxide to methane) and residual volatile fatty acids to valuable chemicals and fuels and even straight to power generation. However, the selection of pretreatment is a vital step. The techno-economic analysis also suggested the high economic feasibility of integrated-anaerobic digestion. Therefore, with the incorporation of pretreatment and anaerobic digestion, the process could have high economic viability attributed to bioenergy production and cost savings through sustainable leachate management options.  相似文献   
248.
Jatoi  Abdul Sattar  Ahmed  Shoaib  Muhammad  Atta  Mubarak  Nabisab Mujawar  Mazari  Shaukat Ali  Abro  Rashid  Memon  Abdul Qayoom  Shah  Asif  Anjum  Amna  Iqbal  Arshad 《SILICON》2022,14(13):7383-7398
Silicon - The demand for the development of high-performance and eco-friendly nanocomposites is soaring up. This is because of their desired mechanical, thermal, electrical, magnetic, catalytic,...  相似文献   
249.
L. acidophilus is a homofermentative, microaerophilic, short chain gram positive microorganism with rod morphology having its bacteriocins belonging to class II a. Several bacteriocins of L. acidophilus have been isolated and characterized. These are structurally similar, but their molecular weight varies as well as their spectrum of antimicrobial activity. They exhibit important technical properties, i.e., thermostability and retaining of activity at a wide pH range along with strong inhibitory actions against food spoilage and pathogenic bacteria make them an important class of biopreservatives. L. acidophilus can be added as an adjunct in many food fermentation processes contributing to unique taste, flavor, and texture. It also preserves the products by producing lactic acid and bacteriocins. A lot of new information regarding the bacteriocins of L. acidophilus has emerged during the last few years. In this review, an attempt has been made to summarize and discuss all the available information regarding the sources of bacteriocins production, their characteristics, and their antimicrobial action along with their application.  相似文献   
250.
Structural and morphological investigations on optimized nano-structured gold thin film (under vacuum ∼10−3 Torr) are reported. The Au optimized thin film was deposited on 4 N polished and analytic grade p-type single crystal (111) Silicon wafer by pulsed laser deposition (PLD) technique, under a vacuum of about 10−3 Torr at room temperature. The space resolved dynamics of the plume is studied by analyzing CCD images of plume. Average size of deposited nanoparticles is along the preferred (111) orientation is ∼ 20 nm using PLD technique. The deposited film is non-uniform with particle size within the range of 6.19 nm-19.62 nm. There is decrease in the value of dislocation line density. XRD and SEM investigations support each other.  相似文献   
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