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31.
Das Internet der Dinge (IoT) bezeichnet die Anbindung von Gegenständen des alltäglichen Gebrauchs an das Internet. Der Fernseher ist als Smart-TV bereits Teil des Internets. Einige Untersuchungen haben hier in jüngster Vergangenheit deutliche Missstände in Bezug auf Datenschutz und Datensicherheit aufgezeigt. Der Beitrag fasst die Ergebnisse einer aktuellen, umfangreichen Untersuchung von fünf Smart-TVs zusammen.  相似文献   
32.
Determining relationships between different types of quantum correlations in open composite quantum systems is important since it enables the exploitation of a type by knowing the amount of another type. We here review, by giving a formal demonstration, a closed formula of the Bell function, witnessing nonlocality, as a function of the concurrence, quantifying entanglement, valid for a system of two noninteracting qubits initially prepared in extended Werner-like states undergoing any local pure-dephasing evolution. This formula allows for finding nonlocality thresholds for the concurrence depending only on the purity of the initial state. We then utilize these thresholds in a paradigmatic system where the two qubits are locally affected by a quantum environment with an Ohmic class spectrum. We show that steady entanglement can be achieved and provide the lower bound of initial state purity such that this stationary entanglement is above the nonlocality threshold thus guaranteeing the maintenance of nonlocal correlations.  相似文献   
33.
This work builds on papers published in Transactions during 2015 and 2018 reporting research into low-cost commercial methods for the prevention of nickel release from decorative nickel plated articles, rendering them suitable for placement on the European market in accordance with the requirements of REACH. ‘Nickel Allergy’ sometimes occurs when nickel-containing articles are in direct and prolonged contact with the skin, leading to corrosion of elemental nickel by sweat, liberating sufficient nickel ions to be absorbed through the skin and initiate an allergenic effect. The EU ‘Nickel Restrictions’ impose limits on the amount of nickel released from articles intended for use in this application, but permits a non-nickel surface coating that can ensure the rate of nickel release does not exceed 0.5?µg?cm?2 week?1 after 2 years of normal use. The official tests for coated items are simulated wear and corrosion under EN 12472 followed by determination of nickel release under EN 1811. Earlier work concluded that suitable barrier coatings over bright electrodeposited nickel are regular chromium deposited from a hexavalent electrolyte, microporous trivalent chromium from a chloride electrolyte and UV cured PU electrophoretic coatings. Further tests reported here focused on nickel release from examples of wearable articles such as costume jewellery and watch cases. A typical flash coating of gold over bright nickel is thin and porous and being more noble, causes the rate of nickel release to be accelerated; but this can be prevented by an intermediate barrier coating of electrodeposited palladium. To round out the relevance of this study on wearable articles, nickel release tests were also conducted on nickel-containing Grades 304 (UNS S30400) and 316 (UNS S31600) austenitic stainless steels, plus a typical gold alloy containing nickel. All passed the nickel release tests satisfactorily.  相似文献   
34.
Ink drops have to be filled into the square cells for an electrowetting display panel. Several ink solutions such as dodecane, tetradecane, and hexadecane were used as test liquids. These fluids have viscosities less than 4 mPas and surface tensions between 23.3 and 26 mN/m and contact angles less than 50°. A slot coating die was employed to deliver these liquids to fill up the square cells. The effects of several parameters such as coating thickness and coating speed were examined. Operating windows inside which the stable filling is possible could be found for these liquids. Several defects were observed outside the operating windows. A flow visualization technique was applied to observe the fluid motion in the coating bead region, particularly the movements of upstream and downstream menisci, the mechanism of liquid filling was discussed.  相似文献   
35.
This paper is devoted to the characterization and processing of high molar mass vinyl‐bearing polysiloxanes in high consistency silicone rubber (HCR) formulations. The molar masses of five different polydimethylsiloxane gums, bearing vinyl groups at the ends and along their chains, were evaluated by size exclusion chromatography and rheometry. 29Si and 1H NMR spectroscopy allowed the precise determination of the vinyl content and of the distribution in the different polymers. Typical HCRs formulated from these gums were heat‐cured to process silicone rubber materials that were then tested mechanically. The macromolecular properties were correlated to the final material network structure. The amount of reactive vinyl moieties, rather than their distribution along or at the end of chains, is a key parameter to tailor the material mechanical properties. © 2016 Society of Chemical Industry  相似文献   
36.
To identify potential biomarkers for improving diagnosis of melioidosis, we compared plasma metabolome profiles of melioidosis patients compared to patients with other bacteremia and controls without active infection, using ultra-high-performance liquid chromatography-electrospray ionization-quadruple time-of-flight mass spectrometry. Principal component analysis (PCA) showed that the metabolomic profiles of melioidosis patients are distinguishable from bacteremia patients and controls. Using multivariate and univariate analysis, 12 significant metabolites from four lipid classes, acylcarnitine (n = 6), lysophosphatidylethanolamine (LysoPE) (n = 3), sphingomyelins (SM) (n = 2) and phosphatidylcholine (PC) (n = 1), with significantly higher levels in melioidosis patients than bacteremia patients and controls, were identified. Ten of the 12 metabolites showed area-under-receiver operating characteristic curve (AUC) >0.80 when compared both between melioidosis and bacteremia patients, and between melioidosis patients and controls. SM(d18:2/16:0) possessed the largest AUC when compared, both between melioidosis and bacteremia patients (AUC 0.998, sensitivity 100% and specificity 91.7%), and between melioidosis patients and controls (AUC 1.000, sensitivity 96.7% and specificity 100%). Our results indicate that metabolome profiling might serve as a promising approach for diagnosis of melioidosis using patient plasma, with SM(d18:2/16:0) representing a potential biomarker. Since the 12 metabolites were related to various pathways for energy and lipid metabolism, further studies may reveal their possible role in the pathogenesis and host response in melioidosis.  相似文献   
37.
38.
With recent moves to implement lead-free manufacturing in the electronics industry, more attention is being paid to the use of tin. One of greatest limitations regarding the reliability of tin is the undesirable development of tin whiskers. Many factors have been identified as being the cause of these whiskers, though tin corrosion has not. Three types of tin deposit grain structures have been developed in an effort to reduce the growth of whisker formations as type (A) with vertical and regular grain boundary; type (B) with horizontal and irregular grain boundary; and type (C) as a combination of both vertical (the top layer) and horizontal (the bottom layer) grain structures. We kept a series of samples in an oven for 1 year at 55 °C/85 % RH (relative humidity), and then used focused ion beam to examine the corrosion microstructure that occurred three types of deposit structures. We found the preferred path of corrosion to occur along the grain boundary and that tin oxide enlarges the volume of the deposit. In order to release the compressive stress that developed during corrosion, whiskers were formed as the grain structure being vertical. Corrosion developed in different locations of various deposits made of the three grain structures. We studied resulting in whisker growth, cracking and the development of internal oxide.  相似文献   
39.
Drawing from the lessons learnt from the Fukushima nuclear disaster in Japan, the assessment of subsurface environmental hazard around nuclear power plants has emerged as a critical task. Consequently, aiming to better understand the possible environmental impact of radiation leaks into the groundwater, a prescreening programme was initiated in 2011 by the Taiwanese government. As part of this programme, this study conducted various borehole prospecting techniques to identify in situ hydrogeological characteristics at Chin‐Shan Nuclear Power Plant. Borehole electrical log, sonic log and temperature/conductivity log were conducted to explain the regional lithologic conditions and permeability of the formation. In conjunction with this, the interwell tracer and pumping test was carried out to simultaneously determine the hydraulic parameters. In our opinion, the implementation of such in situ end‐to‐end investigations is essential in interpreting in situ fluid and solute transport dynamics prior to programming any numerical scheme for early warning, vulnerability assessment and regular monitoring of a nuclear power plant site.  相似文献   
40.
This paper presents one wafer level packaging approach of quartz resonator based on through-silicon via (TSV) interposer with metal or polymer bonding sealing of frequency components. The proposed silicon-based package of quartz resonator adopts several three-dimensional (3D) core technologies, such as Cu TSVs, sealing bonding, and wafer thinning. It is different from conventional quartz resonator using ceramic-based package. With evaluation of mechanical structure design and package performances, this quartz resonator with advanced silicon-based package shows great manufacturability and excellent performance to replace traditional metal lid with ceramic-based interposer fabrication approach.  相似文献   
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