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51.
With the emergence of the COVID-19 pandemic, the World Health Organization (WHO) has urged scientists and industrialists to explore modern information and communication technology (ICT) as a means to reduce or even eliminate it. The World Health Organization recently reported that the virus may infect the organism through any organ in the living body, such as the respiratory, the immunity, the nervous, the digestive, or the cardiovascular system. Targeting the abovementioned goal, we envision an implanted nanosystem embedded in the intra living-body network. The main function of the nanosystem is either to perform diagnosis and mitigation of infectious diseases or to implement a targeted drug delivery system (i.e., delivery of the therapeutic drug to the diseased tissue or targeted cell). The communication among the nanomachines is accomplished via communication-based molecular diffusion. The control/interconnection of the nanosystem is accomplished through the utilization of Internet of bio-nano things (IoBNT). The proposed nanosystem is designed to employ a coded relay nanomachine disciplined by the decode and forward (DF) principle to ensure reliable drug delivery to the targeted cell. Notably, both the sensitivity of the drug dose and the phenomenon of drug molecules loss before delivery to the target cell site in long-distance due to the molecules diffusion process are taken into account. In this paper, a coded relay NM with conventional coding techniques such as RS and Turbo codes is selected to achieve minimum bit error rate (BER) performance and high signal-to-noise ratio (SNR), while the detection process is based on maximum likelihood (ML) probability and minimum error probability (MEP). The performance analysis of the proposed scheme is evaluated in terms of channel capacity and bit error rate by varying system parameters such as relay position, number of released molecules, relay and receiver size. Analysis results are validated through simulation and demonstrate that the proposed scheme can significantly improve delivery performance of the desirable drugs in the molecular communication system.  相似文献   
52.
In this work, CuFe2O4/CuO nanocomposites have been synthesized by galvanostatic cathodic electrodeposition. The obtained nanocomposites were characterized by field emission scanning electron microscopy, transmission electron microscopy, X-ray powder diffraction, Fourier Transform Infrared, and Brunauer–Emmett–Teller surface area analysis. The electrochemical properties of CuFe2O4/CuO nanocomposites were evaluated by cyclic voltammetry, galvanostatic charge–discharge cycling, and electrochemical impedance spectroscopy in 1.0 M KOH. The CuFe2O4/CuO nanocomposites have shown the high specific capacitance of 322.49 F g?1 at the scan rate of 1 mV s?1. After 5000 cycles, 92% of this specific capacitance was retained. Although the prepared nanocomposite has shown a mediocre specific capacitance compared to other metal oxide-based materials, the low cost of the starting materials and the ease of preparation make this nanocomposite a good candidate for supercapacitor applications.  相似文献   
53.
This paper deals with the electromagnetic transients in transformer substations. The substation can have more than one transformer. Generally, these parallel-connected transformers can be of different sizes and neutral treatment. The substation is fed from a high-voltage overhead transmission line (or cable). Emphasis is given to the substation terminal voltage, the transformers' neutral voltages (if their neutrals are not directly earthed) as well as the internal distribution of transient voltages along the transformers' windings, following a typical external double-exponential surge voltage. The distributed parameter transient analysis is done in the s-domain, and then followed by a numerical Laplace inverse transform technique to get the distributions in time domain  相似文献   
54.
In this study, a new optically active poly(ester-imide) (PEI) was synthesized from the polymerization reaction of N,N′-(pyromellitoyl)-bis-l-phenylalanine diacid with 4,4′-thiobis(2-tert-butyl-5-methylphenol) using tosyl chloride, pyridine and N,N-dimethyl formamide as a condensing agent. The obtained polymer and inorganic metal oxide bionanocomposites composed of poly(ester-imide)/titanium dioxide were synthesized through ultrasonic irradiation. The formation of PEI was confirmed by 1H NMR, fourier transform IR spectroscopy (FT-IR), specific rotation and elemental analysis. The resulting bionanocomposites were characterized by FT-IR, powder X-ray diffraction (XRD), atomic force microscopy)AFM(, scanning electron microscopy (SEM), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and thermogravimetric analysis (TGA). The TEM, SEM and FE-SEM results indicated that the nanoparticles were dispersed homogeneously in PEI matrix on nanoscale. TGA confirmed that the heat stability of the nanocomposite was improved in the presence of TiO2 nanoparticles.  相似文献   
55.
Carboxylic functionalized multi-walled carbon nanotubes (MWCNTs) have been incorporated to biodegradable poly(ester-imide) (PEI) matrix and the effect of the carboxylated-MWCNT on the thermal and morphological properties of MWCNT-reinforced bionanocomposites (BNCs) was demonstrated. Chiral PEI was synthesized from a step-growth polymerization of amino acid based diacid (4) with 4,4′-thiobis(2-tert-butyl-5-methylphenol) (5) promoted by tosyl chloride in pyridine and N,N-dimethyl formamide solution. The resulting BNCs were analyzed by Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and thermogravimetric analysis (TGA). The homogeneous dispersion of MWCNTs throughout PEI matrix and strong interfacial adhesion between them were achieved in the obtained BNCs as evidenced by FE-SEM and TEM images. The results from TGA indicated that the thermal stability of the resulting BNCs was obviously improved in comparison with the pure PEI.  相似文献   
56.
Previous intrapericardial left pneumonectomy and irradiation necessitated an unorthodox, staged approach to myocardial revascularization in a patient with unstable angina pectoris, left main artery, and three-vessel coronary artery disease. A saphenous vein bypass graft was constructed from the descending thoracic aorta to the left anterior descending coronary artery via left thoracotomy, without cardiopulmonary bypass. Two days later the patient underwent stenting of the left main and circumflex coronary arteries. Recovery was uneventful.  相似文献   
57.
Guidelines for the proper selection of solar array and battery sizes for use in photovoltaic-powered dispersed systems located far from public power networks are presented. The choice of key design parameters of separately excited DC motors used for farm irrigation is addressed. The selection procedure is based on accurate system modeling and annual simulation using actual meteorological and typical load data. The procedure determines the useful, dumped, and commercial energy components forced by system-load interaction. Two systems are investigated. System one is an AC residential load of a given annual demand profile on hourly basis, while system two represents an irrigation set-up featuring a DC motor and a battery back-up. The results show that a properly sized battery interface would enhance the performance of the irrigation system by more than 12% compared to the directly coupled case  相似文献   
58.
The sodium tungstate‐catalyzed (10 mol %) oxidation of primary amines with a urea‐hydrogen peroxide complex (UHP) gives the corresponding N‐monoalkylhydroxylamines, which are important biologically active compounds, in good to excellent yields. The method is applicable for a wide range of primary amines, including chiral benzylic amines, α‐1,2‐hydroxylamine and α‐amino esters.  相似文献   
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