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1.
Experimental measurements and full-2D numerical simulations show that velocity saturation effects in polysilicon thin-film transistor (TFTs) cannot be neglected in order to obtain a precise modelling of output characteristics. Since full-2D numerical simulations are time consuming and unpractical for circuit simulations, we have developed a new quasi-2D model, that takes into account both velocity saturation effects and the presence of a longitudinal electric field in the Poisson's equation, and includes the effect of parasitic bipolar transistor (PBT) action to reproduce kink effect. The agreement of the quasi-2D model with experimental data from p-channel polysilicon TFTs is very satisfactory even for short channel device, and the presence of a velocity-saturated region with a nearly constant free carrier concentration is reproduced without introducing further assumptions.  相似文献   
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Recent natural disasters have led crisis management organizations to revise their protocols so as to rely on the contribution of a wider range of actors, including simple citizens as well as expert operators, to support decision making activities. Reliable and timely information sharing among members of distributed teams of disaster responders has become paramount for the success of the overall crisis management process. In this paper we propose a crisis management system based on spreadsheet-mediated collaboration among on-site responders and decision makers. To share data a common spreadsheet artifact has been developed by using a participatory design approach which is accessed through mobile user interfaces. The evaluation results showed that the use of the spreadsheet artifact has resulted in more effective decision making relating to set of earthquake management scenarios in high-risk areas located in Italy.  相似文献   
4.
Polyurethane prepolymers prepared from toluene 2,4‐diisocyanate, toluene 2,6‐diisocyanate, and polypropylene glycol with a ratio between the isocyanate and hydroxyl groups equal to 2 were analyzed by 1H nuclear magnetic resonance (NMR) spectroscopy in acetone‐d6. Different temperatures and concentrations were used. Toluene 2,4‐dimethylurethane and toluene 2,6‐dimethylurethane were synthesized and used as model compounds to assign prepolymers signals. Measurements of spin–lattice relaxation time T1 by “inversion recovery” experiments were carried out on toluene 2,4‐diisocyanate, toluene 2,6‐diisocyanate, toluene 2,4‐dimethylurethane, toluene 2,6‐dimethylurethane, and polyurethane prepolymers. Differences in T1 times were used to interpret prepolymers spectra, by means of the strong observed effect on protons due to the presence of adjacent isocyanate groups. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 347–357, 2003  相似文献   
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The interferometric correlation method can provide a simple and inexpensive solution for pollution imagery, especially in the case of a spatially localized gaseous cloud. We describe herein a general method for designing an interferometric correlator for the analysis of any pollutant gas that has regularly distributed absorption spectral lines. We also present a setup using a birefringent interferometer in front of a simplified camera formed by a plano-convex lens and a linear CCD sensor; this demonstrates the monitoring of SO(2) gas. Results from the laboratory simulation show the feasibility of this method. Outdoor measurements permit determination of the required conditions for on-site real-time measurement.  相似文献   
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All-d Heuslers are a category of novel compounds combining versatile functionalities such as caloric responses and spintronics with enhanced mechanical properties. Despite the promising transport properties (anomalous Hall (AHC) and anomalous Nernst (ANC) conductivities) shown in the conventional Co2XY Heuslers with p-d hybridization, the all-d Heuslers with only d-d hybridization open a new horizon to search for new candidates with outstanding transport properties. In this work, the AHC and ANC are evaluated for thermodynamically stable ferro/ferri-magnetic all-d-metal regular Heusler compounds based on high-throughput first-principles calculations. It is observed that quite a few materials exhibit giant AHCs and ANCs, such as cubic Re2TaMn with an AHC of 2011 S cm-1, and tetragonal Pt2CrRh with an AHC of 1966 S cm-1 and an ANC of 7.50 A m-1K-1. Comprehensive analysis on the electronic structure reveals that the high AHC can be attributed to the occurrence of the Weyl nodes or gapped nodal lines in the neighborhood of the Fermi level. The correlations between such transport properties and the number of valence electrons are also thoroughly investigated, which provides a practical guidance to tailor AHC and ANC via chemical doping for transverse thermoelectric applications.  相似文献   
7.
The ability to process and dimensionally scale field‐effect transistors with and on paper and to integrate them as a core component for low‐power‐consumption analog and digital circuits is demonstrated. Low‐temperature‐processed p‐ and n‐channel integrated oxide thin‐film transistors in the complementary metal oxide semiconductor (CMOS) inverter architecture are seamlessly layered on mechanically flexible, low‐cost, recyclable paper substrates. The possibility of building these circuits using low‐temperature processes opens the door to new applications ranging from smart labels and sensors on clothing and packaging to electronic displays printed on paper pages for use in newspapers, magazines, books, signs, and advertising billboards. Because the CMOS circuits reported constitute fundamental building blocks for analog and digital electronics, this development creates the potential to have flexible form factor computers seamlessly layered onto paper. The holistic approach of merging low‐power circuitry with a recyclable substrate is an important step towards greener electronics.  相似文献   
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This paper describes the development and performance of a new rapid amperometric biosensor for fructose monitoring in food analysis. The biosensor is based on the activity of fructose dehydrogenase (FDH) immobilised into a carbon nanotube paste electrode according to two different procedures. The direct wiring of the FDH in a highly original osmium-polymer hydrogel was found to offer a better enzyme entrapment compared to the immobilisation of the enzyme in an albumin hydrogel. The optimised biosensor required only 5 U of FDH and kept the 80% of its initial sensitivity after 4 months. During this time, the biosensor showed a detection limit for fructose of 1 μM, a large linear range between 0.1 and 5 mM, a high sensitivity (1.95 μA cm−2 mM), good reproducibility (RSD = 2.1%) and a fast response time (4 s).  相似文献   
10.
Biliary tract cancers (BTC) represent a heterogeneous and aggressive group of tumors with dismal prognosis. For a long time, BTC has been considered an orphan disease with very limited therapeutic options. In recent years a better understanding of the complex molecular landscape of biology is rapidly changing the therapeutic armamentarium. However, while 40–50% of patients there are molecular drivers susceptible to target therapy, for the remaining population new therapeutic options represent an unsatisfied clinical need. The role of immunotherapy in the continuum of treatment of patients with BTC is still debated. Despite initial signs of antitumor-activity, single-agent immune checkpoint inhibitors (ICIs) demonstrated limited efficacy in an unselected population. Therefore, identifying the best partner to combine ICIs and predictive biomarkers represents a key challenge to optimize the efficacy of immunotherapy. This review provides a critical analysis of completed trials, with an eye on future perspectives and possible biomarkers of response.  相似文献   
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