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21.
Coronavirus disease (COVID-19) is a contagious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This case report presents a patient who had difficulty eradicating the corona virus due to being treated with Rituximab, which depletes B lymphocyte cells and therefore disables the production of neutralizing antibodies. The combined use of external anti-viral agents like convalescent plasma, IVIG and Remdesivir successfully helped the patient’s immune system to eradicate the virus without B-cell population recovery. In vitro studies showed that convalescent plasma is the main agent that helped in eradicating the virus.  相似文献   
22.
We report the growth of graded InGaN nanowires by plasma-assisted molecular beam epitaxy. Wire composition is linearly graded from InN to GaN along the length of each wire. The large lattice mismatch between GaN and InN (11%) introduces tensile strain in the graded region, which results in cracking of the wires. Growing with reverse grading (i.e., GaN to InN) results in crack-free nanowires. The composition is measured by energy-dispersive x-ray spectroscopy of individual nanowires performed in a scanning transmission electron microscope, and strain is measured by high-resolution x-ray diffraction.  相似文献   
23.
An improved deep submicrometer (0.25 μm) MOSFET radio-frequency (RF) large signal model that incorporates a new breakdown current model and drain-to-substrate nonlinear coupling was developed and investigated using various experiments. An accurate breakdown model is required for deep submicrometer MOSFETs due to their relatively low breakdown voltage. For the first time, this RF nonlinear model incorporates the breakdown voltage turnover trend into a continuously differentiable channel current model and a new nonlinear coupling circuit between the drain and the lossy substrate. The robustness of the model is verified with measured pulsed I-V, S-parameters, power characteristics, harmonic distortion, and intermodulation distortion levels at different input and output termination conditions, operating biases, and frequencies  相似文献   
24.
We present a C-band monolithic microwave integrated circuit (MMIC) transmitter module development for multichannel RF/optical subcarrier multiplexed (OSCM) communication applications. The C-band MMIC transmitter module consists of one fully monolithic four-channel OSCM transmitter IC and four coupled-line filters. This MMIC is designed and implemented in a commercial GaAs MESFET process and coupled line bandpass filters are fabricated on the module board. We present the design and performance of the first fully monolithic IC transmitter module for OSCM packet switched applications  相似文献   
25.
LC-tank oscillators in the 5~6 GHz frequency range have been designed and implemented in a commercial 0.6 μm GaAs MESFET technology. One is a voltage-controlled oscillator (VCO), and the other is an oscillator without a controlling element. The output frequency range of the VCO is from 5.44 to 6.14 GHz, and the measured phase-noise is -101.67 dBc/Hz at an offset frequency of 600 KHz from the 5.44 GHz carrier. The phase-noise of the 6.44 GHz oscillator is -108 dBc/Hz at an offset frequency of 600 KHz, and the phase-noise curve, in the offset frequency range between 100 KHz and 1 MHz, shows a -20 dB/decade slope. These phase-noise characteristics are comparable to, or better than, those of the reported 5~6 GHz-band CMOS oscillators. To our knowledge, this is the first GaAs MESFET-based oscillator which has a cross-coupled differential topology and a capacitive coupling feedback to suppress the up-conversion of 1/f noise. Also, it is first reported that the GaAs MESFET-based oscillator shows 1/f2 phase-noise behavior across the offset frequency range from 100 KHz to 1 MHz  相似文献   
26.
The combination of resonant tunneling diodes (RTDs) and complementary metal-oxide-semiconductor (CMOS) silicon circuitry can offer substantial improvement in speed, power dissipation, and circuit complexity over CMOS-only circuits. We demonstrate the first integrated resonant tunneling CMOS circuit, a clocked 1-bit comparator with a device count of six, compared with 21 in a comparable all-CMOS design. A hybrid integration process is developed for InP-based RTDs which are transferred and bonded to CMOS chips. The prototype comparator shows sensitivity in excess of 106 VIA, and achieves error-free performance in functionality testing. An optimized integration process, under development, can yield high-speed, low power circuits by lowering the high parasitic capacitance associated with the prototype circuit  相似文献   
27.
We present a design of experiments (DOE) technique for microwave/millimeter wave flip‐chip characterization and optimization. Two optimization approaches, signal bump misalignment and transmission line compensation, are combined together for optimal performance for high frequency operation. First, the design of experiments method is presented and its advantages are emphasized. Then, the two techniques are combined together in a factorial experiment with the purpose of optimizing the return loss to any desired frequency. The experiment is based on test structure fabrication and measurements. The one‐factor‐at‐a‐time strategy shows that return loss performance is increased with the misalignment values and decreased with compensation for the frequency range of interest. However, the statistical analysis revealed that the optimal performance is achieved for maximum compensation, and minimum misalignment. The optimal structure is measured from 1 to 75 GHz and shows return loss better than 17 dB. The method can be extended to include more optimization factors in different analysis intervals. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
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29.
In this letter, we present a novel ultra-compact embedded IC integration approach for system-on-package (SOP) based solutions for RF and wireless communication applications. This concept is applied to the integration of a Ku band VCO module. The module fabrication is described and the impact of the packaging on the chip-set performances is discussed. The final thickness of the module is about 150 /spl mu/m. The embedded VCO exhibits an oscillation frequency of 15.4 GHz, a phase noise of -99.2 dBc/Hz at a 1 MHz offset and maximum output power of 10.67 dBm. Multilayer interconnects built with modified MCM-D technology using advanced photosensitive epoxy Intervia 8000 is described. Characterization and modeling of RF inductors are detailed and show quality factor as high as 80 at 10 GHz.  相似文献   
30.
A number of alkyl fumarate–vinyl acetate copolymers were prepared and evaluated as flow improvers for high waxy Borholla crude oil. Alkyl fumarate–vinyl acetate copolymers having 19·2 as the average carbon number of the alkyl group in combination with polybehenyl acrylate were found to show optimum activity. Alkyl fumarate–vinyl acetate copolymers reduce the pour point, plastic viscosity and yield stress considerably and polybehenyl acrylate prevents the crude oil from attaining the gel structure on prolonged storage.  相似文献   
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