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81.
Gramegna G. Paparo M. Erratico P.G. De Vita P. 《Solid-State Circuits, IEEE Journal of》2001,36(7):1010-1017
A sub-1-dB noise figure HBM ESD-protected [-3 kV, 2.3 kV] low noise amplifier (LNA) has been integrated in a 0.35-μm RF CMOS process with on-chip inductors. The sensitivity of the LNA performances to the spread of parasitics associated with package and bondwire has been attenuated by using an inductive on-chip source degeneration. At 920 MHz and Pdc=8.6 mW, the LNA features: noise figure NF=1 dB, input return loss=-8.5 dB, output return loss=-27 dB, power gain G p=13 dB, input IIP3=-1.5 dBm. At a power dissipation of 5 mW and 17.6 mW, a NF respectively equal to 1.2 dB and 0.85 dB is measured. The CMOS LNA takes 12 pins of a TQFP48 package, an area of 1.0×0.66 mm2 (bondwire pads excluded) and it is the first HBM ESD-protected [-3 kV, 2.3 kV] CMOS LNA to break the 1-dB NF barrier 相似文献
82.
Maria Assunta Previtali Marcella Mastromatteo Pasquale De Vita Donatella Bianca Maria Ficco Amalia Conte Matteo Alessandro Del Nobile 《International Journal of Food Science & Technology》2014,49(11):2382-2390
In this study, the characterisation of functional bread based on wholemeal durum wheat flour enriched with lentil flour was investigated to find a good balance between the nutritional and organoleptic properties of the final product. In particular, the effect of different percentage of lentil flour (10%, 20% and 25%) and the type and amount of structuring agents (carboxymethyl cellulose, guar seed flour, pectin and tapioca starch) were studied by assessing the sensorial, textural and nutritional properties of the functional bread. Results showed that the increase in the lentil flour at 20% and 25% negatively affected the dough texture and the sensorial quality of the bread. The screening of different hydrocolloids on the bread sample enriched with 25% of legume flour highlighted that the guar seed flour at concentration of 2% allowed obtaining the best results in terms of sensory properties. The nutritional analysis of the optimised functional bread showed an increase in proteins and dietary fibre (total, soluble and insoluble), suggesting its high functional value and the possibility to propose it on a market that is constantly changing and attentive to health benefit of foods. 相似文献
83.
84.
Arun A Le Poche H Idda T Acquaviva D Badia MF Pantigny P Salet P Ionescu AM 《Nanotechnology》2011,22(2):025203
In this work, tunable MEMS capacitors are realized using a vertically grown carbon nanotube array. The vertical CNT array forms an effective CNT membrane, which can be electrostatically actuated like the conventional metal plates used in MEMS capacitors. The CNT membrane is grown on titanium nitride metal lines, with a Al/Fe bi-layer as buffer layer and catalyst material respectively, using chemical vapor deposition process. Two different anchor configurations are investigated. A maximum capacitance of 400 fF and maximum tunability of 5.8% is extracted from the S-parameter measurements. Using the tunable MEMS vertical array capacitor a voltage controlled oscillator (VCO) is demonstrated showing promise for integrating CNTs for communications applications. 相似文献
85.
Elena Bartkiene Gerhard Schleining Grazina Juodeikiene Daiva Vidmantiene Vita Krungleviciute Toma Rekstyte Loreta Basinskiene Mantas Stankevicius Ieva Akuneca Ona Ragazinskiene Audrius Maruska 《LWT》2014
The aim of the study was to investigate if differences in acidification, biogenic amines (BA) and volatile compounds (VC) occurred when Lactobacillus sakei KTU05-6, Pediococcus acidilactici KTU05-07 and Pediococcus pentosaceus KTU05-8 are used as starters in solid state fermentation of flaxseed and the impact of flaxseed sourdough on the wheat bread making process assessed. 相似文献
86.
Greta Motiekaityte Aukse Navaruckiene Vita Raudoniene Danguole Bridziuviene Justinas Jaras Kristina Kantminiene Jolita Ostrauskaite 《应用聚合物科学杂志》2023,140(2):e53289
Considering the current efforts for to develop new antimicrobial polymers from renewable resources suitable for application in environmentally friendly light-based technologies, novel dual-cured photopolymers of vanillin alcohol diglycidyl ether and glycerol dimethacrylate are developed. The kinetics of the sequential and simultaneous dual-curing processes, combining free radical and cationic photopolymerizations, is investigated by real-time photorheometry. Comparison of dual-curing systems with different ratios of biobased epoxy and acrylate monomers revealed that the increase in the acrylate content increases the photocuring rate and improves the mechanical performance (Young's modulus increases from 76.64 to 190.71 MPa) and thermal stability (the 10% weight loss increases from 227 to 274°C) of the polymers, while the increase in the vanillin epoxy content results in better antimicrobial activity. Developed photopolymers create unfavorable conditions for the growth of microorganisms and reduce their population by up to 0% in 24 h. The excellent antibacterial and antifungal activity of new photopolymers allows them to be considered as biobased alternatives to petroleum-based antimicrobial coatings, films, or optical 3D printed objects. 相似文献
87.
A new technique for offset loss and spot-size measurement in single-mode fibres has been developed. It consists in coupling the fibre with its image from a spherical mirror (or an equivalent optical system) and overcomes the problems of the traditional offset techniques. 相似文献
88.
A systematic approach to modeling and assessing gracefully degrading systems, exploiting the formalism offered by Petri nets, is provided. The procedure followed is based on the definition of some fundamental modules, the composition of which allows a complete model of the system to be obtained. The model can then be solved by computer simulation or analytically by means of a class of Petri nets to obtain interesting performability parameters either at steady state or when the system is time-varying. A number of real cases are examined and the results obtained are described 相似文献
89.
We report a patient who had refractory Hodgkin's disease and who received an autologous bone marrow transplantation and 8 months later developed abdominal pain associated with acute colonic dilation. The course of the patient was rapidly fatal due to a lobar pneumonia. Autopsy revealed signs of disseminated herpesvirus infection with marked hemorrhagic infarction of celiac sympathetic ganglia. This finding supports the hypothesis that denervation caused by virus reactivation and secondary hemorrhage is a main mechanism of acute colonic pseudoobstruction. 相似文献
90.
The alpha/beta scaffold of the scorpion toxin charybdotoxin has been used for the engineering of a metal binding site. Nine substitutions, including three histidines as metal ligands, have been introduced into the original toxin sequence. The newly designed sequence, 37 amino acids long, has been assembled by solid-phase synthesis and HBTU (2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate) coupling of Fmoc-protected amino acids. Formation of the three disulfide bonds occurred efficiently and rapidly in the presence of glutathione, and this post-synthesis modification has facilitated the purification task enormously. The process of synthesis and purification was performed in less than a week with an overall 10.2% yield. Circular dichroism analysis showed that the newly designed protein is folded in a alpha/beta structure, similarly to the parent toxin. Electronic absorption spectroscopy, circular dichroism and gel filtration experiments have been used to show that Cu2+ and Zn2+ ions bind with high affinity to the newly engineered protein. These results demonstrate that the alpha/beta fold, common to all scorpion toxins, is a very versatile basic structure, tolerant for substitutions and able to present new sequences in a predetermined conformation. The chemical approach is shown to be effective, rapid and practical for the production of novel designed small proteins. 相似文献