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A novel gelatin/montmorillonite–chitosan (Gel/MMT–CS) nanocomposite scaffold was prepared via the intercalation process and the freeze-drying technique, using the ice particulates as the porogen materials. Properties including pore structure, water adsorption content, in vitro degradation and tensile strength were investigated. It was demonstrated that the introduced intercalation structure endowed the Gel/MMT–CS scaffold with good mechanical properties and a controllable degradation rate. Scanning of the electron microscope images revealed that the scaffold obtained was highly porous and suitable for the implanted cells to adhere and grow. The mitochondrial activity assay provided good evidences of cells viability on the Gel/MMT–CS membranes, giving an indication of possible application as a matrix for tissue engineering.  相似文献   
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IntroductionAll hospitals in the province of Styria (Austria) are well equipped with sophisticated Information Technology, which provides all-encompassing on-screen patient information. Previous research made on the theoretical properties, advantages and disadvantages, of reading from paper vs. reading from a screen has resulted in the assumption that reading from a screen is slower, less accurate and more tiring. However, recent flat screen technology, especially on the basis of LCD, is of such high quality that obviously this assumption should now be challenged. As the electronic storage and presentation of information has many advantages in addition to a faster transfer and processing of the information, the usage of electronic screens in clinics should outperform the traditional hardcopy in both execution and preference ratings.This study took part in a County hospital Styria, Austria, with 111 medical professionals, working in a real-life setting. They were each asked to read original and authentic diagnosis reports, a gynecological report and an internal medical document, on both screen and paper in a randomly assigned order. Reading comprehension was measured by the Chunked Reading Test, and speed and accuracy of reading performance was quantified. In order to get a full understanding of the clinicians' preferences, subjective ratings were also collected.ResultsWilcoxon Signed Rank Tests showed no significant differences on reading performance between paper vs. screen. However, medical professionals showed a significant (90%) preference for reading from paper. Despite the high quality and the benefits of electronic media, paper still has some qualities which cannot provided electronically do date.  相似文献   
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This paper analyzed the deformation mechanism in lateral roof roadway of the Ding Wu-3 roadway which was disturbed by repeated mining of close coal seams Wu-8 and Wu-10 in Pingdingshan No. 1 Mine. To determine the strata disturbance scope, the strata displacement angle was used to calculate the protection pillar width. A numerical model was built considering the field geological conditions. In simulation, the mining stress borderline was defined as the contour where the induced stress is 1.5 times of the original stress. Simulation results show the mining stress borderline of the lateral roadway extended 91.7 m outward after repeated mining. Then the original stress increased, deforming the roadway of interest. This deformation agreed with the in situ observations. Moreover, the strata displacement angle changed due to repeated mining. Therefore, reselection of the displacement angle was required to design the protective pillar width. Since a constant strata displacement angle was used in traditional design, the proposed method was beneficial in field cases.  相似文献   
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Time is ubiquitous. Accounting for time and its interaction with change is crucial to modeling the dynamic world, especially in domains whose study of data is sensitive to time such as in medical diagnosis, financial investment, and natural language processing, to name a few. We present a framework that incorporates both uncertainty and time in its reasoning scheme. It is based on an existing knowledge representation called Bayesian Knowledge Bases. It provides a graphical representation of knowledge, time and uncertainty, and enables probabilistic and temporal inferencing. The reasoning scheme is probabilistically sound and the fusion of temporal fragments is well defined. We will discuss some properties of this framework and introduce algorithms to ensure groundedness during the construction of the model. The framework has been applied to both artificial and real world scenarios.  相似文献   
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Nickel modified rhodanine (Rh) self-assembled monolayer films (Rh-SAM/Ni) were fabricated on copper from 10.0 mM Rh containing methanol. The films were characterized with the help of scanning electron microscopy (SEM), atomic force microscopy (AFM) and energy dispersive X-ray spectroscopy (EDX) techniques. The methanol oxidation activity of the Rh-SAM/Ni electrode was tested in 1.0 M methanol containing 0.1 M KOH solution using many electrochemical techniques. The results indicated that well-ordered and very homogeneously distributed Rh-SAM films were assembled over the copper surface. The rate of methanol electrooxidation reaction can be enhanced by modifying copper surface with Rh-SAM/Ni multi-layer film. The enhanced activity was related to increasing active sites over the surface for adsorption and oxidation of methanol as well as facilitating oxidation or desorption of adsorpted intermediates of the process. It was suggested that the Rh-SAM layer could be a candidate supporting material for fabricating direct methanol fuel cell (DMFCs) anodes.  相似文献   
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The sluggish activity of cathode at intermediate-temperature limits commercialization of proton-conducting solid oxide fuel cells (H-SOFCs). In this investigation, a novel cathode of Ba0.95Ca0.05Fe0.85Sn0.05Y0.1O2.9−δF0.1 was successfully developed by co-doping of anion F and cations Ca, Sn, Y. We studied the effect of F-doping on phase structure, electrical conductivity and electrochemical properties of the cell. Compared with Ba0.95Ca0.05Fe0.85Sn0.05Y0.1O3−δ, F-doped Ba0.95Ca0.05Fe0.85Sn0.05Y0.1O3−δ exhibited higher conductivity. Composite cathode consisting of Ba0.95Ca0.05Fe0.85Sn0.05Y0.1O2.9−δF0.1 and Sm0.2Ce0.8O2−δ was applied in H-SOFCs with BaZr0.1Ce0.7Y0.2O3−δ electrolyte which achieves an encouraging performance with the maximum power density of 1050 mW cm−2 and polarization resistance of 0.04 Ω cm2 at 700 °C. The result of First-principles calculations based on spin-polarized Density Functional Theory shows that doping of F reduces the activation energy required for migration of oxygen ions. These results demonstrate that the anions and cations co-doped strategy can provide a new horizon for the cathode in H-SOFCs.  相似文献   
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We report on efficient solution-processed phosphorescent white polymer light-emitting diodes (WPLEDs) with tunable color-correlated temperature (CCT) and color rendering index (CRI), through rationally controlling the composition of the emission layer (EML) based on a near-infrared (NIR)-emitting dinuclear cyclometalated platinum (II) complex bridged with NˆS anionic ligand, named (niq)2Pt2(μ-C8PhOXT)2 (Pt-1, in which PhOXT is 5-(phenyl-1,3,4-oxadiazole)-2-thiol, niq is 1-naphthylisoquinolinato), a sky-blue emitter iridium (III) bis[(4,6-di-fluorophenyl)-pyridinato-N,C2] (picolinate) (FIrpic), and a yellow emitter bis[2-(thieno[3,2-c]pyridin-4-yl)phenyl]iridium(III)(acetylacetonato) (PO-01). One of the best three-color WPLEDs shows a CCT of 3246 K as well as an excellent high CRI of 87, which are greatly beneficial in reducing deep-blue light damage and simultaneously meet the requirement for good color reproduction. Meanwhile, the relevant WPLED also achieves a maximum current efficiency of 12.1 cd/A, corresponding to an external quantum efficiency of 10.6%. This work presents an effective approach through rational combination of sky-blue, yellow, and NIR emitters towards high-performance solution-processable WPLEDs with a physiologically-friendly CCT and a high CRI.  相似文献   
10.
The objective of this paper is to provide a synthetic tool for determining expeditiously the wave climate conditions in several areas of the Mediterranean Sea. In the open literature, several authors have already conducted this specific analysis also for the area under examination in this paper. However, the need of discussing aspects strictly related to the design of wave energy harvesters is still relevant. Therefore, considering the variety of devices and the amount of information needed for conducting both an energy-wise optimization and a structural reliability assessment, a holistic view on the topic is provided. Specifically, the paper elucidates the theoretical aspects involved in the estimation of wave energy statistics and in the calculation of relevant return values. Next, it provides synthetic data representing the mean wave power and the return value of extreme events in several coastal areas of the Mediterranean Sea. In this regard, the paper complements information available in the open literature by discussing the influence of the directional pattern of the sea states in the determination of sea state statistics as well as in the design of a wave energy harvester.  相似文献   
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