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291.
Wojciech Knap Salman Nadar Hadley Videlier Stephane Boubanga-Tombet Dominique Coquillat Nina Dyakonova Frederic Teppe Kristoph Karpierz Jerzy ?usakowski Maciej Sakowicz Irmantas Kasalynas Dalius Seliuta Gintaras Valusis Taiichi Otsuji Yahya Meziani Abdel El Fatimy Simon Vandenbrouk Kamel Madjour Didier Th��ron Christophe Gaqui��re 《Journal of Infrared, Millimeter and Terahertz Waves》2011,32(5):618-628
Resonant frequencies of the two-dimensional plasma in field effect transistors (FETs) increase with the reduction of the channel dimensions and can reach the Terahertz (THz) range. Nonlinear properties of the plasma/electron gas in the transistor channel can be used for the rectification and detection of THz radiation. The excitation of plasma waves by sub-THz and THz radiation was demonstrated for short gate transistors at cryogenic temperatures. At room temperature plasma oscillations are usually overdamped, but the FETs can still operate as efficient broadband rectifiers/detectors in the THz range. We present a few recent experimental results on THz detection by FETs showing some new ways of improvement of FETs for THz imaging at room temperature as well as the new physical phenomena like detection in quantizing magnetic fields. We also demonstrate THz emission properties of GaN based FETs. 相似文献
292.
Louchouarn P Chillrud SN Houel S Yan B Chaky D Rumpel C Largeau C Bardoux G Walsh D Bopp RF 《Environmental science & technology》2007,41(1):82-87
Soot black carbon (here expressed as GBC) is present in sediments of Central Park and Prospect Park Lakes, New York City (NYC), and peaks in the middle of the 20th Century at the highest values (1-3% dry weight) ever reported in urban lakes. During that period (approximately 1940-1970), the GBC represents up to 28% of the total organic carbon (OC). Radionuclide-normalized whole core inventories of accumulated GBC are similar in the two lakes which are separated by approximately 15 km, suggesting that emissions of fine soot particles may have accumulated homogeneously over at least the urban center of NYC. The distribution of polycyclic aromatic hydrocarbons (PAHs) in the sediments is decoupled from that of GBC. The highest levels of total PAHs correspond to peak coal use for space heating in NYC in the early 1900s. In contrast, GBC concentrations were highest in the mid 1900s, a period when oil combustion dominated local fossil fuel use and incineration of municipal solid waste (MSW) was common practice in NYC. Decreases in GBC levels observed in more recently deposited sediments are consistent with improvements in particle emissions control systems. Non-soot BC (char) was identified by a high carbon to nitrogen (C/N) ratio that persisted after correction for GBC. This likely tracer of MSW incineration was estimated to contribute an additional '35% of total organic carbon found in the sediments deposited during the peak period of combustion. The temporal trends of soot-BC observed in our lake cores do not agree with published historical reconstructions based on fuel consumption and estimated emission factors. 相似文献
293.
Velimir Mladenov Vasileios Fotopoulos Eirini Kaiserli Erna Karalija Stephane Maury Miroslav Baranek Naama Segal Pilar S. Testillano Valya Vassileva Glria Pinto Manuela Nagel Hans Hoenicka Dragana Miladinovi Philippe Gallusci Chiara Vergata Aliki Kapazoglou Eleni Abraham Eleni Tani Maria Gerakari Efi Sarri Evaggelia Avramidou Mateo Gaparovi Federico Martinelli 《International journal of molecular sciences》2021,22(13)
Although epigenetic modifications have been intensely investigated over the last decade due to their role in crop adaptation to rapid climate change, it is unclear which epigenetic changes are heritable and therefore transmitted to their progeny. The identification of epigenetic marks that are transmitted to the next generations is of primary importance for their use in breeding and for the development of new cultivars with a broad-spectrum of tolerance/resistance to abiotic and biotic stresses. In this review, we discuss general aspects of plant responses to environmental stresses and provide an overview of recent findings on the role of transgenerational epigenetic modifications in crops. In addition, we take the opportunity to describe the aims of EPI-CATCH, an international COST action consortium composed by researchers from 28 countries. The aim of this COST action launched in 2020 is: (1) to define standardized pipelines and methods used in the study of epigenetic mechanisms in plants, (2) update, share, and exchange findings in epigenetic responses to environmental stresses in plants, (3) develop new concepts and frontiers in plant epigenetics and epigenomics, (4) enhance dissemination, communication, and transfer of knowledge in plant epigenetics and epigenomics. 相似文献
294.
Anne Emmanuelle Berger Aude Gleizes Louis Waeckel Xavier Roblin Roman Krzysiek Salima Hacein-Bey-Abina Alessandra Soriano Stephane Paul 《International journal of molecular sciences》2022,23(17)
Background. Monitoring of biological TNF inhibitors is a very important tool to guide clinical decisions using specialized algorithms, especially in gastroenterology. A new chemiluminescent instrument (i-TRACK10® from Theradiag) could replace ELISA techniques to calculate the dosage of drugs and anti-drug antibodies. In this bi-centric study, we explored the analytical performances of i-TRACK10® using manual or automated (DS2®) ELISA Lisa-Tracker® assays, and compared the results. Patients and methods. Intra- and inter-run performances were evaluated with i-TRACK10® in two different laboratories and for two different ranges of values for infliximab, adalimumab, and their respective antibodies. Patients’ samples were used in the labs to compare the results obtained between the new instrument and either the manual Lisa-Tracker® or the automated DS2. Results. Intra- and inter-run performances were satisfactory, with values between 1.8% and 16.1% (for inter-run imprecision at low/medium values of infliximab). Results were generally comparable between assays. with the lowest value of correlation at 0.59 (anti-adalimumab dosage between i-TRACK10® and manual ELISA). Most often, values of drugs and anti-drug antibodies were higher with i-TRACK10® than with manual ELISA assay, and correlation values were better with automated ELISA. Agreements were globally acceptable, and the lowest coefficients of 0.7 was obtained for adalimumab values between i-TRACK10® and the two ELISA methods, and for anti-adalimumab values between i-TRACK10® and manual ELISA. The type of assay can potentially induce a change in the class of patients and lead to divergent therapeutic decisions. Conclusions. The new random-access instrument i-TRACK10® presents many advantages in a routine laboratory: rapidity, the possibility of standardization, usability, and expansion of the measurement range. Despite the relatively good agreement of results, it is preferable to use the same assay in longitudinal follow-up of a patient, because quantitative results were not completely equivalent especially for anti-drug antibodies. 相似文献
295.
Ultra-Small YPO4-YAG:Ce Composite Nanophosphors with a Photoluminescence Quantum Yield Exceeding 50%
Yige Yan Adel Mesbah Lhoussain Khrouz Corinne Bouillet Chantal Lorentz Nicholas Blanchard Anne C. Berends Marie Anne van de Haar Frédéric Lerouge Michael R. Krames Ovidiu Ersen Frédéric Chaput Stephane Parola 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(26):2208055
Synthesis of high quality colloidal Cerium(III) doped yttrium aluminum garnet (Y3Al5O12:Ce3+, “YAG:Ce”) nanoparticles (NPs) meeting simultaneously both ultra-small size and high photoluminescence (PL) performance is challenging, as generally a particle size/PL trade-off has been observed for this type of nanomaterials. The glycothermal route is capable to yield ultra-fine crystalline colloidal YAG:Ce nanoparticles with a particle size as small as 10 nm but with quantum yield (QY) no more than 20%. In this paper, the first ultra-small YPO4-YAG:Ce nanocomposite phosphor particles having an exceptional QY-to-size performance with an QY up to 53% while maintaining the particle size ≈10 nm is reported. The NPs are produced via a phosphoric acid- and extra yttrium acetate-assisted glycothermal synthesis route. Localization of phosphate and extra yttrium entities with respect to cerium centers in the YAG host has been determined by fine structural analysis techniques such as X-ray diffration (XRD), solid state nuclear magnetic resonance (NMR), and high resolution scanning transmission electron microscopy (HR-STEM), and shows distinct YPO4 and YAG phases. Finally, a correlation between the additive-induced physico-chemical environment change around cerium centers and the increasing PL performance has been suggested based on electron paramagnetic resonance (EPR), X-ray photoelectron spectrometry (XPS) data, and crystallographic simulation studies. 相似文献
296.
Delavand Ovono Ovono Giovanni Bruno Philippe Pradeau Stephane Berre 《International Journal of Applied Glass Science》2013,4(1):20-30
The effect of nucleating agent content and of the crystallization heat treatment have been explored on a commercial lithium-aluminosilicate (LAS) composition (Eurokera Kerablack). Using X-ray diffraction (XRD) on treated samples and differential scanning calorimetry (DSC), we have observed that crystallization occurs differently in nucleating agent-depleted materials than in standard LAS. In particular, we found larger grain size and β-spodumene content than in KeraBlack. We also assessed the decisive effect of the heating rate: although nucleation can take place under almost arbitrary conditions (except with no nucleating agent), the final materials depend on the crystallization cycle applied. They contain more β-quartz with smaller grain size if the cycles and the soak treatments are short; they consist mainly of β-spodumene with large grains if the ramps and soak times are long. We also observed that a soak heat treatment does not influence the crystallization in the case of low content of nucleating agents, but can be used to obtain crystallization if only ZrO2 is added. The impact of nucleating agents underlines the importance of heterogeneous nucleation in these glass-ceramics. We conclude that it is not possible to create a fine-grained LAS glass-ceramic without the proper amount of nucleating agents. 相似文献
297.
298.
Mohamed El Jaafari Nicolas Chuberre Stephane Anjuere Laurent Combelles 《International Journal of Satellite Communications and Networking》2023,41(3):220-238
With the recent publication of a set of technical specifications in 3rd Generation Partnership Project (3GPP) related to non-terrestrial network (NTN) enhancements, a global standard for satellite systems is newly defined aiming to support any orbit, any frequency band, and any device. It opens the door for the seamless integration of satellite network component in 5G system and beyond, delivering the promise of a ubiquitous mobile system that can support new use cases. The emergence of hybrid terrestrial-satellite systems is the result of a joint effort between stakeholders of both mobile and satellite industries and is paving the way to new business opportunities. This paper attempts to provide a comprehensive view on this 3GPP NTN standard and what are the next steps. 相似文献