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11.
Nathalie C. Mougin Patrick van Rijn Hyunji Park Axel H. E. Müller Alexander Böker 《Advanced functional materials》2011,21(13):2470-2476
New bionanoparticles have been prepared from horse spleen ferritin by grafting thermoresponsive poly(N‐isopropyl acrylamide) (PNIPAAm) and photo‐crosslinkable 2‐(dimethyl maleinimido)‐N‐ethyl‐acrylamide (DMIAAm) from the protein surface. The 72 addressable amino groups on the exterior of HSF were modified with N‐hydroxysuccinimide‐activated 2‐bromo‐isobutyrate to form a macro‐initiator for atom transfer radical polymerization, which was performed in water/DMF solutions at low temperature. The modification of the HSF and the presence of the polymer shell were confirmed by size exclusion chromatography (SEC), sodium dodecyl sulfate‐polyacrylamide gel‐electrophoresis, transmission electron microscopy, and scanning force microscopy. The thermoresponsive behavior of the ferritin‐PNIPAAm conjugates was investigated in solution by UV–vis spectroscopy showing a phase transition in the form of a cloud point around 32 °C. Further, dynamic light scattering revealed an increasing hydrodynamic radius around this transition, indicating aggregation of the particles at elevated temperatures which was confirmed by transmission electron microscopy. Initial experiments show that the particles are highly surface active, much more than the individual components alone, which was demonstrated by pendant‐drop interfacial tension measurements. This leads to the fact that they form stable Pickering emulsions, i.e., emulsion droplets decorated with polymer‐modified bionanoparticles which can be cross‐linked successively. This allows the formation of capsules with thermoresponsiveness for controlled release purposes, e.g., in drug delivery. 相似文献
12.
Design challenges of a 65 nm CMOS stacked folded differential PA structure for mobile communications
Yohann Luque Nathalie Deltimple Eric Kerhervé Didier Belot 《Analog Integrated Circuits and Signal Processing》2011,66(2):155-162
In this paper, a novel phase-locked loop (PLL) architecture with multiple charge pumps, which is used to design a fast-locking
PLL and a low-phase-noise PLL, is proposed. The effective capacitance and resistance of the loop filter in terms of voltage
is scaled up/down according to the locking status by controlling the magnitude and direction of the charge pump current. Two
PLLs, one with a fast-locking characteristic and the other with a low-phase-noise characteristic, are designed and fabricated
in a 0.35-μm CMOS process based on the proposed architecture. The fast-locking PLL has a locking time of less than 6 μs and
a phase noise of −90.45 dBc/Hz at 1 MHz offset. The low-phase-noise PLL has a locking time of 25 μs, a phase noise of −105.37 dBc/Hz
at 1 MHz offset, and a reference spur of −50 dBc. Both PLLs have an 851.2 MHz output frequency. 相似文献
13.
Yong‐Ning Zhou Mahsa Sina Nathalie Pereira Xiqian Yu Glenn G. Amatucci Xiao‐Qing Yang Frederic Cosandey Kyung‐Wan Nam 《Advanced functional materials》2015,25(5):696-703
Searching high capacity cathode materials is one of the most important fields of the research and development of sodium‐ion batteries (SIBs). Here, we report a FeO0.7F1.3/C nanocomposite synthesized via a solution process as a new cathode material for SIBs. This material exhibits a high initial discharge capacity of 496 mAh g?1 in a sodium cell at 50 °C. From the 3rd to 50th cycle, the capacity fading is only 0.14% per cycle (from 388 mAh g?1 at 3rd the cycle to 360 mAh g?1 at the 50th cycle), demonstrating superior cyclability. A high energy density of 650 Wh kg?1 is obtained at the material level. The reaction mechanism studies of FeO0.7F1.3/C with sodium show a hybridized mechanism of both intercalation and conversion reaction. 相似文献
14.
A multiparameter wearable physiologic monitoring system for space and terrestrial applications. 总被引:4,自引:0,他引:4
Carsten W Mundt Kevin N Montgomery Usen E Udoh Valerie N Barker Guillaume C Thonier Arnaud M Tellier Robert D Ricks Robert B Darling Yvonne D Cagle Nathalie A Cabrol Stephen J Ruoss Judith L Swain John W Hines Gregory T A Kovacs 《IEEE transactions on information technology in biomedicine》2005,9(3):382-391
A novel, unobtrusive and wearable, multiparameter ambulatory physiologic monitoring system for space and terrestrial applications, termed LifeGuard, is presented. The core element is a wearable monitor, the crew physiologic observation device (CPOD), that provides the capability to continuously record two standard electrocardiogram leads, respiration rate via impedance plethysmography, heart rate, hemoglobin oxygen saturation, ambient or body temperature, three axes of acceleration, and blood pressure. These parameters can be digitally recorded with high fidelity over a 9-h period with precise time stamps and user-defined event markers. Data can be continuously streamed to a base station using a built-in Bluetooth RF link or stored in 32 MB of on-board flash memory and downloaded to a personal computer using a serial port. The device is powered by two AAA batteries. The design, laboratory, and field testing of the wearable monitors are described. 相似文献
15.
16.
Sofiane Aloui Nicolas Delaunay Eric Kerherve Nathalie Deltimple Robert Plana Didier Belot 《Analog Integrated Circuits and Signal Processing》2012,70(2):203-211
A millimeter-wave Power Amplifier (PA) based on a 65nm CMOS technology from STMicroelectronics has been designed. The targeted feature is the unlicensed band around 60 GHz suitable for wireless personal area network application (WPAN). To optimize the linearity, the PA is designed under class A biasing to have an output compression point (OCP1) close to its saturated Power (P sat). S-parameters and large signal measurement results are demonstrated and compared with electromagnetic simulations. The PA offers a P sat of 8.3 dBm, an OCP1 of 6 dBm and a gain of 6.7 dB. The die area is 0.29 mm2 with pads. Considering those results, one-tone simulations are not sufficient to characterize the linearity performances of the PA in its real conditions of use. Consequently, two-tone simulations are firstly performed. After, linearity figures of merit (FoM) are discussed applying an orthogonal frequency-division multiplexing (OFDM) modulated signal. The PA offers an adjacent channel power ratio (ACPR) of 15 dB and an error vector magnitude (EVM) of 20% at PA compression operating mode. 相似文献
17.
The effects of static, alternating and dynamic stress conditions on the degradation rate of 0.8μm n- and p-channel LDD MOS transistors have systematically been investigated and compared. The shifts of the threshold voltage, transconductance, linear drain current and charge pumping current were used to monitor the transistor degradation. The results suggest that the aging induced by a dynamic stress cannot be directly explained with static stress models, essentially because it is highly dependent on a larger number of parameters (biases and durations of the top and bottom levels of the pulses, transient times). The correlation of static and dynamic stresses also clarifies the degradation mechanisms, in particular the role of hot holes in the generation of interface states. 相似文献
18.
Susana M Cardoso Sylvain Guyot Nathalie Marnet Jos A Lopes‐da‐Silva Catherine MGC Renard Manuel A Coimbra 《Journal of the science of food and agriculture》2005,85(1):21-32
Methanol extracts of olive pomace (two‐phase olive oil extraction) and olive pulp were analysed by reverse phase HPLC and the eluted fractions were characterised by electrospray ionisation mass spectrometry. This technique allowed the identification of some common phenolic compounds, namely, verbascoside, rutin, caffeoyl‐quinic acid, luteolin‐4‐glucoside and 11‐methyl‐oleoside. Hydroxytyrosol‐1′‐β‐glucoside, luteolin‐7‐rutinoside and oleoside were also detected. Moreover, this technique enabled the identification, for the first time in Olea europaea tissues, of two oleoside derivatives, 6′‐β‐glucopyranosyl‐oleoside and 6′‐β‐rhamnopyranosyl‐oleoside, and of 10‐hydroxy‐oleuropein. Also, an oleuropein glucoside that had previously been identified in olive leaves was now detected in olive fruit, both in olive pulp and olive pomace. With the exception of oleoside and oleuropein, the majority of phenolic compounds were found to occur in equivalent amounts in olive pulp and olive pomace. Oleoside was the main phenolic compound in olive pulp (31.6 mg g?1) but was reduced to 3.6 mg g?1 in olive pomace, and oleuropein (2.7 mg g?1 in the pulp) almost disappeared (<0.1 mg g?1 in the pomace). Both these phenolic compounds were degraded during the olive oil extraction process. Copyright © 2004 Society of Chemical Industry 相似文献
19.
Buche P Dervin C Gnanou-Besse N Brouillaud-Delattre A 《International journal of food microbiology》2002,73(2-3):171-185
Various predictive models of microbial behavior have been created and extensive data collection has been done by numerous private or public laboratories. However, significant differences between predicted and observed values in foods have been observed and need to be stressed, understood and explained as much as possible. In this paper, we present a software tool (currently at the level of a prototype) able: (i) to store in a database all relevant information expressed on one hand as qualitative or quantitative data and on the other hand as precise or imprecise data; (ii) to retrieve the more relevant information from the database using queries where criteria may be expressed as fuzzy values in order to enhance the flexibility of the search: (iii) to compute, in addition to the nearest data, an estimation of searched values using statistical models. The architecture of this software tool is structured as a category-based reasoning system. Example queries about Listeria monocytogenes (L. monocytogenes) illustrate the functionalities of this tool. 相似文献
20.