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排序方式: 共有307条查询结果,搜索用时 15 毫秒
281.
Emilie Bernard T. Ernst B. Guillaumot N. Vulliet X. Garros V. Maffini-Alvaro P. Coronel T. Skotnicki S. Deleonibus 《Solid-state electronics》2008,52(9):1297-1302
In this study, we integrate and compare the electrical performances of metal/high-K embedded gates in 3D multi-channel CMOSFETs (MCFETs) on SOI. The electrical characteristics of embedded gates obtained by filling cavities with TiN/HfO2, TiN/SiO2 or N+ poly-Si/SiO2 are compared to a planar reference. In particular, we investigate electron and hole mobility behaviours (300 K down to 20 K) in embedded and planar structures, the gate leakage current and the negative bias temperature instability (NBTI). Despite a lower mobility, TiN/HfO2 gate stack demonstrates the best ION/IOFF compromise and exhibits NBTI life time higher than 10 years up to 1.3 V. 相似文献
282.
Tristan Pichonat Christophe Lethien Nicolas Tiercelin Sylvie Godey Emmanuelle Pichonat Pascal Roussel Marie Colmont Paul Alain Rolland 《Materials Chemistry and Physics》2010
First step in the way to the fabrication of an all-solid microbattery for autonomous wireless sensor node, amorphous thin solid films of lithium phosphorus oxynitride (LiPON) were prepared by radio-frequency sputtering of a mixture target of P2O5/Li2O in ambient nitrogen atmosphere. The morphology, composition, and ionic conductivity were characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and A.C. impedance spectroscopy. With a thickness of 1.4 μm, the obtained LiPON amorphous layer provided an ionic conductivity close to 6 × 10−7 S cm−1 at room temperature. MicroRaman UV spectroscopy study was successfully carried out for the first time on LiPON thin films to complete the characterization and bring further information on LiPON structure. 相似文献
283.
284.
Ballandras S Steichen W Briot E Solal M Doisy M Hodé JM 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2004,51(1):121-126
Analysis of the quartz properties shows the existence of unexplored angular domains for which Rayleigh waves can be efficiently excited, exhibiting physical characteristics better than the ones of the (ST,X) cut. This paper presents a family of quartz cuts allowing significant improvements of surface acoustic wave (SAW) devices on quartz. A first set of experiments has been performed, confirming the theoretical predictions of the basic properties of SAW on these cuts. A second set of measurements then was achieved to refine the identification of coefficients needed to perform industrial SAW design. A demonstration of the improvements accessible using this new cut is presented. A low loss SAW filter working at 71 MHz has been fabricated using smaller aluminum thickness than that for standard quartz cuts, and exhibiting all the properties required for its industrial implementation. 相似文献
285.
Photoreactive analogues of substance P (biotin sulfone-spacer (amino pentanoic or Gly(3))-Arg-Pro-Lys-Pro-(pBzl)Phe-Gln-Phe-Phe-Gly-Leu-Met(O(2))NH(2)) with or without isotope (deuterium) labeling have been synthesized. Deuteriums were present on (d)-biotin or epibiotin sulfone (D(3)), on the Gly(3) spacer linker (D(6)), or on the Gly in position 9 of SP (D(2)). Therefore, peptide analogues could be either unlabeled or tri-, penta-, or hexadeuterated. Results obtained with the use of these peptide analogues show that (d)-biotin sulfone and epibiotin sulfone are not recognized with the same affinity by streptavidin, with (d)-biotin sulfone displaying better affinity for the protein. Photolabeling of the human NK-1 receptor with a 1:1 molar ratio of nondeuterated and deuterated photoreactive substance P (SP) analogues in position 5, followed by combined digestions, purification, and MALDI-TOF mass spectrometry analysis, made the identification of the domain of the receptor covalently linked by the photoreactive SP analogue easier. Indeed, doublets in mass spectra were specific for the covalent complex whereas single peaks could be attributed to contaminating species. This method is particularly suitable when minute amounts of complex have to be analyzed, as in the case of highly hydrophobic G-protein coupled receptors. 相似文献
286.
Emmanuelle Graux Nour Mohammad Murad David Carsenat Bernard Jecko 《Wireless Personal Communications》2007,41(3):365-377
The aim of this paper is to study a 2 × 2 Multiple-Input Multiple-Output (MIMO) with antenna’s coupling phenomena at the transmitters
and at the receivers. The single motivation of this study is to show how to choose a couple of couplings in order to reach
a fixed Signal to Noise Ratio according to the application considered. It is shown, that a certain combination of couplings
can make the system more powerful. 相似文献
287.
INTRODUCTION: Non-fatal road casualties are under-reported, with official figures coming from the police. In the French Rh?ne county, a road trauma registry constitutes a second source of reporting but its completeness needs to be assessed. We also wish to estimate an incidence rate of non-fatal road casualties that is corrected for under-count. METHODS: Having two sources of reporting available, we can apply the capture-recapture method under certain conditions. To take into account different reporting probabilities among casualties, the capture-recapture analysis is stratified according to injury severity (New Injury Severity Score=NISS), road user type and human third party. To evaluate the sensitivity of the capture-recapture estimate on the number of matched casualties between the police file and the registry, three scenarios of record-linkage are considered. RESULTS: For serious (NISS 9+) non-fatal road casualties, the police ascertainment rate is at most 57%, the registry ascertainment rate is at most 87%, and the aggregate ascertainment rate is at most 95%. The ascertainment-corrected incidence rate for serious (NISS 9+) non-fatal road casualties is at least 65 per 100,000. CONCLUSION: The degree of completeness of the registry for serious casualties is rather high, though not satisfactory. 相似文献
288.
Robust 3-D modeling of vasculature imagery using superellipsoids 总被引:1,自引:0,他引:1
Tyrrell JA di Tomaso E Fuja D Tong R Kozak K Jain RK Roysam B 《IEEE transactions on medical imaging》2007,26(2):223-237
This paper presents methods to model complex vasculature in three-dimensional (3-D) images using cylindroidal superellipsoids, along with robust estimation and detection algorithms for automated image analysis. This model offers an explicit, low-order parameterization, enabling joint estimation of boundary, centerlines, and local pose. It provides a geometric framework for directed vessel traversal, and extraction of topological information like branch point locations and connectivity. M-estimators provide robust region-based statistics that are used to drive the superellipsoid toward a vessel boundary. A robust likelihood ratio test is used to differentiate between noise, artifacts, and other complex unmodeled structures, thereby verifying the model estimate. The proposed methodology behaves well across scale-space, shows a high degree of insensitivity to adjacent structures and implicitly handles branching. When evaluated on synthetic imagery mimicking specific structural complexities in tumor microvasculature, it consistently produces ubvoxel accuracy estimates of centerlines and widths in the presence of closely-adjacent vessels, branch points, and noise. An edit-based validation demonstrated a precision level of 96.6% at a recall level of 95.4%. Overall, it is robust enough for large-scale application. 相似文献
289.
Oxidation of Metals - Model γ-NiCrAl alloys with and without titanium were oxidized for short times up to 32 h at 1000 °C and subsequently characterized by scanning... 相似文献
290.
Roth E Schwenninger SM Eugster-Meier E Lacroix C 《International journal of food microbiology》2011,147(1):26-32
In vitro and in situ anti-listerial properties of 3 strains of Facultative Anaerobic Halophilic and Alkaliphilic (FAHA) species, i.e. Alkalibacterium kapii ALK 6, Marinilactibacillus psychrotolerans ALK 9 and Facklamia tabacinasalis ALK 1, were investigated. The 3 strains were isolated from a smear ecosystem originating from a commercial Raclette type cheese and exhibiting strong anti-listerial activity in situ on cheese surface.In a first step, strains were tested in vitro for production of antimicrobial compounds against Listeria innocua 81000-1 and Listeria ivanovii HPB 28. M. psychrotolerans ALK 9 inhibited both indicator strains in spot-on-the-lawn tests while A. kapii ALK 6 showed no inhibiting effect. F. tabacinasalis ALK 1 exerted an in vitro inhibition on L. ivanovii HPB 28, but induced the formation of dense ball-shaped microcolonies of L. innocua 81000-1 in the soft agar, a typical biofilm microstructure. The extent of the biofilm zone was enhanced when F. tabacinasalis ALK 1 and M. psychrotolerans ALK 9 were tested together.In a second step, different combinations of strains were applied on Raclette cheeses ripened at pilot scale and contaminated with 50 cfu/cm2L. innocua at day 7. A control flora of 6 strains, isolated from ecosystem F and corresponding to species commonly found on smear cheeses, was applied on control and test cheeses. In test cheeses, we investigated the impact on Listeria growth of the addition of the 3 FAHA strains, applied as single or mixed cultures. A 1-log inhibition was obtained at day 15 on cheeses treated with FAHA strains applied either as single or mixed cultures. This 1-log inhibition was correlated with the development of FAHA species that reached their maximal count at day 15.This study suggests that the development of FAHA species in early ripening likely contributes to the initial part of the in situ inhibition exerted by the complex cheese surface ecosystem investigated. 相似文献