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41.
Ştefania Adelina Milea Cristian Vasile Dima Elena Enachi Loredana Dumitraşcu Vasilica Barbu Gabriela Elena Bahrim Petru Alexe Nicoleta Stănciuc 《International Journal of Food Science & Technology》2020,55(12):3585-3594
Black rice and lavender are promising sources of bioactives, in terms of anthocyanins and essential oils. Their bioaccessibility were improved by microencapsulation, followed by mixing in order to benefit both from colour and flavour, along with radical scavenging and biological properties. The mixed powder showed a satisfactory anthocyanins of 2.55 mg g−1 DW, leading to a radical scavenging activity of 65.14 mmol g−1 DW. The powder displayed an inhibitory effect against α-glucosidase (~49%) and α-amylase (39%), respectively, with a controlled release in intestinal environment. To further examine the functional properties, the powder was added to a food model system. During storage, a release in anthocyanins and flavonoids were found, leading to an increase in radical scavenging activity. The sensorial analysis showed that supplemented biscuits were appreciated for colour and lavender aroma. The obtained results were promising in tailoring the health benefits of secondary metabolites, underutilised in human’s nutrition due to their low stability and bioavailability. 相似文献
42.
In this paper, a compact asymmetric coplanar waveguide (CPW) feed with split-ring resonator (SRR) is proposed to resonate at dual-band operations for wireless local area network (WLAN) and worldwide interoperability for microwave access (WiMAX) applications. The asymmetric CPW-fed SRR patch (ACSP) antenna consists of a meander line, square-shaped split ring, and CPW ground plane. The proposed ACSP antenna resonates at two operating frequencies, namely, 2.48 GHz (2.4–2.74 GHz) and 3.49 GHz (3.25–3.64 GHz) with reflection coefficients (S11) of −16.65 dB and −32.67 dB, respectively. The measured results agree closely with the simulation results of the proposed antenna. 相似文献
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44.
《Digital Communications & Networks》2020,6(2):229-237
With the rapid development and widespread application of Wireless Body Area Networks (WBANs), the traditional centralized system architecture cannot handle the massive data generated by the edge devices. Meanwhile, in order to ensure the security of physiological privacy data and the identity privacy of patients, this paper presents a privacy protection strategy for Mobile Edge Computing(MEC) enhanced WBANs, which leverages the blockchain-based decentralized MEC paradigm to support efficient transmission of privacy information with low latency, high reliability within a high-demand data security scenario. On this basis, the Merkle tree optimization model is designed to authenticate nodes and to verify the source of physiological data. Furthermore, a hybrid signature algorithm is devised to guarantee the node anonymity with unforgeability, data integrity and reduced delay. The security performance analysis and simulation results show that our proposed strategy not only reduces the delay, but also secures the privacy and transmission of sensitive WBANs data. 相似文献
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46.
Ahmad Reza Abbasian Alireza Mahvary Shahram Alirezaei 《Ceramics International》2021,47(17):23794-23802
The effects of three types of salt including NaF, KCl, and NaCl on the properties of NiFe2O4 nanoparticles using salt-assisted solution combustion synthesis (SSCS) have been investigated. The synthesized powders were evaluated by SEM, TEM, FTIR, XRD, and VSM analysis. Also, the specific surface area (SSA), as well as size distribution and volume of the porosities of NiFe2O4 powders were determined by the BET apparatus. The visual observations showed that the intensity and time of combustion synthesis of nanoparticles have been severely influenced by the type of salt. The highest crystallinity was observed in the synthesized powder using NaCl. The SSA has also been correlated completely to the type of salt. The quantities of SSA was achieved about 91.62, 64.88, and 47.22 m2g-1 for the powders synthesized by KCl, NaCl, and NaF respectively. Although the magnetic hysteresis loops showed the soft ferromagnetic behavior of the NiFe2O4 nanoparticles in all conditions, KCl salt could produce the particles with the least coercivity and remanent magnetization. Based on the present study, the salt type is a key parameter in the SSCS process for the preparation of spinel ferrites. Thermodynamic evaluation also showed that the melting point and heat capacity are important parameters for the proper selection of the salt. 相似文献
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48.
《International Journal of Hydrogen Energy》2021,46(80):39658-39664
Water splitting is an effective way to produce hydrogen to solve the energy crisis problem, and inorganic metal compounds are widely used in electrocatalysis field due to efficient hydrogen evolution reaction (HER). Herein, we synthesize Ni2V2O7 dandelion microsphere from nickel nitrate and vanadium pentoxide by “one-step hydrothermal” way, which exhibits large specific surface area of 102.74 m2 g−1. The as-prepared Ni2V2O7 microsphere shows good electrocatalysis performances including OER overpotential of 358 mV and good stability, as well as HER overpotential of 195 mV. Furthermore, the Ni2V2O7 microsphere electrode is assembled to Ni2V2O7 microsphere//Ni2V2O7 microsphere system, showing the water splitting voltage of 1.50 V at 10 mA cm−2 by two-electrode method, which is much lower than those of commercial RuO2//Pt/C system and most of spinel oxides electrocatalysts. Our work opens up a new and facile avenue for fabricating inorganic microsphere electrocatalyst in hydrogen production field. 相似文献
49.
西藏江达县白格村金沙江右岸于2018年10月11日和2018年11月3日先后发生2次大规模滑坡—堰塞湖堵江事件,溃堰洪水对下游拉哇库区不良地质体的稳定性造成不同程度的影响。为保障下游水电站建设安全,对拉哇库区主要不良地质体建立了基于星载InSAR技术、无人机技术和地面传感器实时监测的“天空地”一体化监测预警体系,以多维空间采集技术获取变形信息,通过智能监控平台对信息及时进行处理、分析和可视化呈现,利用平台、短信等方式向相关人员进行分级告警,取得了较好的应用效果。 相似文献
50.
In the electro-deoxidation process, carbon parasitic reaction (CO32- + 4e-=C + 3O2-) usually occurs when using carbon materials as the anode, which leads to increase of the carbon content in the final metal and decrease of the current efficiency of the process. The aim of this work is to reduce the negative effect of carbon parasitic reaction on the electrolysis process by adjusting anode current density. The results indicate that lower graphite anode area can achieve higher current density, which is helpful to increase the nucleation site of CO2 bubbles. Most of CO2 would be released from the anode instead of dissolution in the molten CaCl2 and reacting with O2- to form CO32-, thus decreasing the carbon parasitic reaction of the process. Furthermore, the results of the compared experiments show that when the anode area decreases from 172.78 to 4.99 cm2, CO2 concentration in the released gases increases significantly, the carbon mass content in the final metal product decreased from 1.09% to 0.13%, and the current efficiency increased from 6.65% to 36.50%. This study determined a suitable anode current density range for reducing carbon parasitic reaction and provides a valuable reference for the selection of the anode in the electrolysis process. 相似文献