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In Vitro PET Imaging of a Miniature Ventricular Assist Device
摘要： Interactions between the life-sustaining ventricular assist devices and diagnostic therapies must be carefully considered to decrease the risk of inaccurate diagnostic imaging or pump failure. Methods: The MVAD? pump, currently under investigational use, was tested for interaction with radiotracers in an in vitro ?ow-loop study. The radiotracers 18F-sodium ?uoride and 18F-FDG were injected into a closed loop to determine the feasibility of direct imaging of the MVAD? pump in a PET scanner. Results: No real-time changes were observed in pump operation, and there were no statistical differences in pump parameters (power consumption, speed, and estimated ?ow rate) between the baseline and circulation conditions. In addition, no effect was observed on any external components, including the permissive-action-link controller and the batteries powering the device. Imaging of the internal pump components was possible, with obscuration observed only in the portion of the pump where the spinning impeller is located. Retention of radiotracer in the pump components after circulation was minimal (,1%). Conclusion: PET imaging is an attractive diagnostic tool for patients with a ventricular assist device and may have additional utility outside its current use, detection of infection.
关键词： ventricular assist device,PET,MVAD?,radioactive,pump
更新于2025-09-11 14:15:04
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[IEEE 2018 43rd International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz2018) - Nagoya, Japan (2018.9.9-2018.9.14)] 2018 43rd International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) - Developments of Equipment for sub- THz Collective Thomson Scattering in LHD
摘要： Equipment for collective Thomson scattering diagnostics in the Large Helical Device has been developed. The probe beam source is a 303 GHz Gyrotron. It operates in a pulse mode. No parasitic mode is excited during the whole pulse width including the turn-on and turn-off phases. Single mode oscillation at several frequencies has been confirmed. For power transmission, a 3.5 inch corrugated waveguide line installed for electron heating with lower frequency gyrotrons will be used. The test with the 303 GHz gyrotron has shown a sufficiently low transmission loss.
关键词： Gyrotron,collective Thomson scattering,corrugated waveguide,sub-THz,Large Helical Device
更新于2025-09-10 09:29:36
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Mesoporous titania-coated biosensor and FEM model design for highly sensitive detection of low molecular weight targets
摘要： This paper presents the interest of a highly sensitive biosensor coated with a TiO2 mesoporous film as sensitive layer. The main novelty is related to the modelling of the device and simulation by using Finite Element Method with COMSOL Multiphysics software, as a good way to take into account the physical properties of porous 3D-layers. The strategy of using such Love wave devices, with 3D porous layers, offering further easy functionalization, aims not only to increase the amount of targets caught on the sensor surface, but also to enhance the detection mechanism by a higher perturbation of the Love wave acoustic energy which could be trapped inside the 3D sensitive layer. First, as a proof of concept, experimental devices with a 3D titania mesoporous layer were realized, and they have shown a good agreement with simulated results. Furthermore, experimental test with several Newtonian liquids are investigated, in a range of viscosities from 1 to 7 cP, typical of those concerned by our biochemical applications. The sensitivity with a 300 nm thick porous sensing layer was 10 times that of the bare device, with interesting dynamical issues to be further studied, giving rise to the great potentialities of such architectures for biological detection of low weight biochemical targets.
关键词： surface to volume ratio,mesoporous materials,biochemical sensing,Radio Frequency Love wave device,finite element modelling,acoustic interaction in liquid medium
更新于2025-09-10 09:29:36
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Electronic exchange-correlation, many-body effect issues on first-principles calculations of bulk SiC polytypes
摘要： The first-principles Projector-Augmented Wave method (PAW) is used to investigate the electronic, phonon band structure and dielectric properties of four bulk silicon carbide (SiC) polytypes. We employ PAW pseudopotential density functional theory with Perdew, Burke and Ernzerhof (PBE) and hybrid HSE06 approximations of the exchange-correlation functional. Many-body effects are incorporated using the GW approximation of the self-interaction to study SiC properties. GW method in its single-shot variant, which is based on the many-body perturbation theory (MBPT), is used to calculate the quasi-particle (QP) energies of the band structure and the dielectric properties for different polytypes. The electronic band structure determination within GW method uses the Wannier procedure where a basis set of maximally localized Wannier function (MLWF) is constructed to interpolate the QP energies of few regular mesh k-points to the high-symmetry lines in Brillouin zone. As a consequence of QP correction to the Kohn–Sham energies, bandgap is increased by upto 3 eV in case of 4H–SiC, as compared to PBE bandgap. GW results are comparable to those of hybrid functionals and are in good agreement with the experimental results. The optical properties are then studied within PBE, HSE06 and include many-body effects. In addition, the phonon band structure has been investigated within HSE06 and compared to previous PBE results. We found good agreement with the previous theoretical results and the experimental available data.
关键词： silicon carbide,semiconductors,Density functional theory,power electronic device,polytypism
更新于2025-09-10 09:29:36
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A Multipurpose Conjugated Polymer: Electrochromic Device and Biosensor Construction for Glucose Detection
摘要： First example of electrochemically polymerized thiazolothiazole containing electrochromic conducting polymer;Poly(2,5-di(furan-2-yl)thiazolo[5,4-d]thiazole) (PTTzFr) was obtained via cyclic voltammetry. The polymer structure bears furan unit as the donor and thiazolothiazole unit as the acceptor. PTTzFr film was obtained on an ITO coated glass slide and its electrochemical and optoelectronic properties were investigated. Polymeric film showed reversible redox behavior along with reversible electrochromic behavior from reddish orange to grey having a band gap value of 1.80 eV. It has fast switching times (0.3 s and 0.4 s) with high optical contrast values at visible and NIR regions (38% at 460 nm and 63% at 1225 nm). Optoelectronic device application was performed by constructing a dual type electrochromic device (ECD) with poly(3,4-ethylenedioxythiophene) (PEDOT). Resulting device showed a remarkable optical memory without changing its % transmittance value during 200 s at 450 nm. Additionally, to construct a sensing interface, in the present work, a conjugated polymer (PTTzFr) containing biosensor was constructed for the glucose analysis. The architecture showed a promising sensing system for biosensor application. For the preparation of the proposed sensor, polymer film was coated on graphite electrode surface and fabricated as a glucose biosensor with immobilization of glucose oxidase. The biosensor was successfully applied for the determination of glucose in beverage. Under optimized conditions, the proposed sensor served a low detection limit (12.8 × 10?3 mM), and high sensitivity (65.44 μAmM?1cm?2). To the best of our knowledge, a sensor design and ECD construction using electrochemically polymerized PTTzFr that shows superior properties for both systems were attempted for the first time, and this approach resulted in improved biosensor and ECD characteristics.
关键词： thiazolothiazole containing conducting polymer,electrochromic device,electrochromic polymer,Amperometric biosensor,glucose biosensor
更新于2025-09-10 09:29:36
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High-Periphery GaN HEMT Modeling up to 65 GHz and 200°C
摘要： In this article, we report on the temperature-dependent GaN HEMT behavior. To evaluate the potentialities of this kind of active solid-state electronic device at its best, the experiments are performed at extreme operating conditions. As a case study, we consider a large 0.25-μm GaN HEMT with a gate periphery of 1.5 mm, providing a high dissipated power of 5.1 W. The tested semiconductor device is characterized by measuring scattering parameters at high frequencies up to 65 GHz and at high ambient temperature up to 200°C. To assess the impact of the thermal effects on high-frequency GaN HEMT performance, an equivalent circuit is analytically extracted and then used to determine the main RF figures of merit. The achieved experimental results show evidence that the increase of the temperature causes a significant degradation in device performance.
关键词： scattering parameter measurements,high-power,GaN HEMT,high-temperature,Active solid-state electronic device,millimeter-wave frequency
更新于2025-09-10 09:29:36
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[IEEE 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Paris, France (2018.7.8-2018.7.13)] 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - One-Gate Ratchet Single-Electron Pump: Device Failure Mechanisms
摘要： Electrical current standards based on the charge of the electron will become more important after the SI redefinition. Many of the best recent charge pump results have come in the one-gate ratchet pumping mode, but this mode is sometimes difficult to achieve. In this work, we discuss the likely reasons for this difficulty, and ways to overcome the difficulty.
关键词： single-electron metrology,One-gate ratchet charge pump,device failure mechanisms
更新于2025-09-10 09:29:36
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[IEEE 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Paris, France (2018.7.8-2018.7.13)] 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Evaluation of JIG Calibration Method for Absorbing Clamp Calibration According to CISPR 16-1-3
摘要： This paper describes JIG method calibration technique for absorbing clamp calibration according to the standard CISPR 16-1-3. Calibration geometrical construction, calibration configuration and its influence to the Clamp Factor (CF) calibration is described.
关键词： vertical flange,JIG calibration method,CISPR 16-1-3,Clamp Factor (CF),Secondary absorbing device (SAD)
更新于2025-09-10 09:29:36
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3.4: Room Temperature Dual Emission of Fluorescence and Phosphorescence in the Solid State
摘要： A white light emission comprised of fluorescence and phosphorescence was observed at room temperature in the solid state. The OLED device used the dual emission material was fabricated and showed white EL light.
关键词： Dual emission OLED device,White emission,Dual emission,Solid state
更新于2025-09-10 09:29:36
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[Nanostructure Science and Technology] Nanowire Electronics || Metal-Semiconductor Compound Contacts to Nanowire Transistors
摘要： Semiconductor nanowires [1–4] are promising building blocks for next-generation ultrascaled devices for electronic [5–7] and optoelectronic [8–10] applications. An important aspect for the development, maturity, and ef?ciency of these ultrascaled devices is the detailed understanding of and control over the phase transformation that accompanies the formation of their compound contacts for lithography-free self-aligned gate design [11, 12]. The term “compound” here refers to the formed phases that have ?xed stoichiometry between metal and semiconductor elements, to be distinguished from the broader “alloy” term for phases that may include nonstoichiometric or amorphous structure. This distinction is important because the formation of a low resistance, crystalline, and thermally stable compound contact is most preferred for realizing reliable functionality in ultrascaled semiconductor transistors. Usually, the phase of compound contact and its interfacial property with semiconductor nanowire (NW) can largely affect the band alignment and charge injection in NW channels. This demands the detailed studies of the metal-semiconductor solid-state reactions, including the formed compound phases, reaction kinetics, and their correlation to the device performances. In this book chapter, we provide a thorough discussion of these three topics.
关键词： metal-semiconductor solid-state reactions,compound contacts,reaction kinetics,phase transformation,Semiconductor nanowires,device performances
更新于2025-09-10 09:29:36