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Wireless Networks - Internet of things consist in the deployment of constrained and battery-powered devices with a radio interface. Most industrial applications require to respect strict...  相似文献   
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People spend approximately 80% of their time indoor, making the understanding of the indoor chemistry an important task for safety. The high surface-area-to-volume ratio characteristic of indoor environments leads the semi-volatile organic compounds (sVOCs) to deposit on the surfaces. Using a long path absorption photometer (LOPAP), this work investigates the formation of nitrous acid (HONO) through the photochemistry of adsorbed nitrate anions and its enhancement by the presence of furfural. Using a high-resolution proton-transfer-reaction time-of-flight mass spectrometer (PTR-TOF-MS), this work also investigates the surface emissions of VOCs from irradiated films of furfural and a mix of furfural and nitrate anions. Among the emitted VOCs, 2(5H)-furanone/2-Butenedial was observed at high concentrations, leading to maleic anhydride formation after UV irradiation. Moreover, the addition of potassium nitrate to the film formed NOx and HONO concentrations up to 10 ppb, which scales to ca. 4 ppb for realistic indoor conditions. This work helps to understand the high levels of HONO and NOx measured indoors.  相似文献   
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International Journal on Software Tools for Technology Transfer - We use runtime verification (RV) to check various specifications in a smart apartment. The specifications can be broken down into...  相似文献   
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A Raman study of a Sèvres soft paste (frit) porcelain plate allowed the identification of both the crystalline and amorphous phases. Cristobalite and pseudowollastonite gave main Raman signatures in the body where also tridymite, amorphous alkali silicate glass and lead arsenate apatite were detected. Na0.4K0.1Ca0.5Pb4(AsO4)3 lacunar apatite is identified as opacifier in blue and green overglaze enamel. Pb-Sb-reach pyrochlore (Naples Yellow) pigment was found in yellow and green overglaze enamels. The orange hue is obtained by superposing a hematite bearing red paint stroke over the yellow. These results are compared to those previously obtained by detailed OM, SEM, XRD and XRF analyses. Some of the phases identified by XRD (quartz, tridymite) are hardly detected by Raman and vice versa cristobalite was not found by XRD, most probably due to its low amount.  相似文献   
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A new kind of high electrical conductive epoxy coating with low filler rate was investigated for lightning strike protection (LSP) of carbon fiber reinforced polymer (CFRP). The coating without CFRP substrate was firstly studied. The influence of silver submicronic wires (AgSWs) with a high aspect ratio on the electrical behavior is observed; that is, the electrical resistivity evolution, the current density value, and the electrical conduction mechanisms as function of temperature. The preponderant electrical conduction mechanism is an Ohmic behavior. The higher level of conductivity obtained is 5.5 × 105 S m−1 for 9% vol of AgSWs. Lightning strike tests were carried out on an epoxy/AgSWs coating filled with 8% in volume (74 gsm) and deposited on a CFRP. The ultrasonic testing after lightning strike on coated CFRP shows no structural delamination and demonstrates the interest of this new route for an efficient LSP. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 137, 48700.  相似文献   
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The estrogenic compound nonylphenol (NP) is frequently found in sludge from sewage treatment works. Hence, when sewage sludge is spread on the land, endocrine-disrupting compounds may get into the soil. The goal of this study was to investigate the extent to which aerobic mesophilic treatment in continuous reactors permits the removal of NP from sludge and how this process may be useful for treating anaerobically stabilised sludge. We also report on the behaviour of NP during the anaerobic treatment of sludge. The reduction in sludge estrogenic activity observed in the different types of treatment, as measured using estrogen-responsive reporter cells lines (MELN bioassay), was compared with NP removal rates. Under anaerobic conditions, no degradation of NP and its estrogenic activity was observed. Indeed, an accumulation of the compound occurred. In contrast, high removal of NP was achieved in aerobic conditions as well as in aerobic Post-treatment of anaerobically pre-digested sludge, with a concomitant reduction of the sludge's estrogenic potency.  相似文献   
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After initiating a provocative discussion on “regional science in crisis” (Bailly and Coffey 1994; Gibson 1994; Plane 1994; Stough 1994; Anas 1994; Vickerman 1994; Casetti 1995), we now wish to present some additional thoughts on how regional scientists can simultaneously make their field more relevant scientifically and more useful for society. At a time when resources are tight, when the number of regional science students is small, when administrators are scrutinizing our budgets and our ability to generate outside money, we need to do something to regain (or is it simply to gain?) our place in the sun. In this paper, we argue that regional scientists will not reestablish their field by using classical approaches to regional analysis alone. It is essential that we look at new ways to answer questions raised by our social, economic, and political institutions. More specifically, we make some observations concerning the history of regional science, its role within universities, and its nature, as well as offering some suggestions concerning how regional scientists can attempt to improve the situation.  相似文献   
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