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51.
    
This study proposed using color components as artificial intelligence (AI) input to predict milk moisture and fat contents. In this sense, an adaptive neuro-fuzzy inference system (ANFIS) was applied to milk processed by moderate electrical field-based non-thermal (NP) and conventional pasteurization (CP). The differences between predicted and experimental data were not significant (p > 0.05) for lightness (L*), redness-greenness (a*), yellowness-blueness (b*), total color differences (∆E), hue angle (h), chroma (C), whiteness (WI), yellowness (YI), and browning index (BI). ANFIS well-predicted milk fat and moisture content using quadratic and two-factor interaction models with mean errors of .00858–.01260 and correlation coefficient of .8051–.8205. Stability tests showed L* and WI reduced while a*, b*, ΔE, h, C, YI, and BI increased during the storage. NP milk had 77.21% higher half-life than CP, as predicted by ANFIS modeling. Findings indicated milk quality characteristics could be estimated based on physical parameters (e.g., color components), contributing to sustainable food production.  相似文献   
52.
    
Ultrathin bismuth exhibits promising performance for topological insulators due to its narrow band gap and intrinsic strong spin–orbit coupling, as well as for energy‐related applications because of its electronic and mechanical properties. However, large‐scale production of 2D sheets via liquid‐phase exfoliation as an established large‐scale method is restricted by the strong interaction between bismuth layers. Here, a sonication method is utilized to produce ultrahigh‐aspect‐ratio bismuthene microsheets. The studies on the mechanism excludes the exfoliation of the layered bulk bismuth and formation of the microsheets is attributed to the melting of spherical particles (r = 1.5 µm) at a high temperature—generated under the ultrasonic tip—followed by a recrystallization step producing uniformly‐shaped ultrathin microsheets (A = 0.5–2 µm2, t: ≈2 nm). Notably, although the preparation is performed in oxygenated aqueous solution, the sheets are not oxidized, and they are stable under ambient conditions for at least 1 month. The microsheets are used to construct a vapor sensor using electrochemical impedance spectroscopy as detection technique. The device is highly selective, and it shows long‐term stability. Overall, this project exhibits a reproducible method for large‐scale preparation of ultrathin bismuthene microsheets in a benign environment, demonstrating opportunities to realize devices based on bismuthene.  相似文献   
53.
    
Developing a facile approach for the manipulation of the direction and order of the enzymatic reactions via sequential immobilization on inexpensive substrates is a continuous demand. Herein, a new methodology is introduced that allows making a desired enzymatic reaction pathway on a paper‐based microfluidic‐membrane based biosensor (P‐µMB). Although the method is universal, here, as a proof‐of‐concept, the sequential immobilization of α‐amylase, glucose oxidase (GOx) and horseradish peroxidase (HRP) is presented for fabricating a P‐µMB. To this end, hydrophilic polydopamine/polyethyleneimine patterns are created on the hydrophobic polypropylene membrane using 3D printing and a polydimethylsiloxane (PDMS) mold, and a coating layer of silver nanoparticles (AgNPs) is used to modify the patterns. The enzymes are then individually immobilized on the desired locations with another set of PDMS molds. It is observed that AgNPs P‐µMB in the sequential immobilization system has stable activity at various temperature and pH regimes, high selectivity toward starch, wide‐range linear sensitivity, and a limit of detection of 0.002% w/w starch. A smartphone camera is used for the quantitative analysis of the analyte with the mean gray intensity as the analytical parameter. This developed system provides a platform for further sequential immobilization of other types of biological elements.  相似文献   
54.
    
A wideband microstrip reflectarray antenna (RA) is proposed using a novel unit‐cell for X‐band applications. The unit‐cell is composed of a logarithmic toothed microstrip element and two‐variable phase‐delay lines (PDLs) for the required phase compensation in the RA. By adjusting the lengths of the PDLs, a smooth and almost linear phase variations of 627° is achieved at the frequency of 10 GHz. Based on the proposed element, a 144‐element center‐fed RA with dimensions of 216 mm × 216 mm is designed at 10 GHz and simulated using CST software. Then, a fabricated prototype RA is tested to validate the design approach. The maximum measured gain is 25.3 dB at 10.4 GHz, whereas the gain is 24.6 dB with 44.2% aperture efficiency at the design frequency of 10 GHz. Also, the measured gain frequency characteristic shows the 1 and 3‐dB gain bandwidths of 24.8% and 42.3%, respectively, and the measured radiation patterns verify the simulated ones as well.  相似文献   
55.
    
Scaling down miniature rotorcraft and flapping-wing flyers to sub-centimeter dimensions is challenging due to complex electronics requirements, manufacturing limitations, and the increase in viscous damping at low Reynolds numbers. Photophoresis, or light-driven fluid flow, was previously used to levitate solid particles without any moving parts, but only with sizes of 1–20 µm. Here, architected metamaterial plates with 50 nm thickness are leveraged to realize photophoretic levitation at the millimeter to centimeter scales. Instead of creating lift through conventional rotors or wings, the nanocardboard plates levitate due to light-induced thermal transpiration through microchannels within the plates, enabled by their extremely low mass and thermal conductivity. At atmospheric pressure, the plates hover above a solid substrate at heights of ≈0.5 mm by creating an air cushion beneath the plate. Moreover, at reduced pressures (10–200 Pa), the increased speed of thermal transpiration through the plate's channels creates an air jet that enables mid-air levitation and allows the plates to carry small payloads heavier than the plates themselves. The macroscopic metamaterial structures demonstrate the potential of this new mechanism of flight to realize nanotechnology-enabled flying vehicles without any moving parts in the Earth's upper atmosphere and at the surface of other planets.  相似文献   
56.
    
Multidrug resistance resulting from a variety of defensive pathways in cancer has become a global concern with a considerable impact on the mortality associated with the failure of traditional chemotherapy. Therefore, further research and new therapies are required to overcome this challenge. In this work, a cyclic R10 peptide (cR10) is conjugated to polyglycerol‐covered nanographene oxide to engineer a nanoplatform for the surmounting of multidrug resistance. The nuclear translocation of the nanoplatform, facilitated by cR10 peptide, and subsequently, a laser‐triggered release of the loaded doxorubicin result in efficient anticancer activity confirmed by both in vitro and in vivo experiments. The synthesized nanoplatform with a combination of different features, including active nucleus‐targeting, high‐loading capacity, controlled release of cargo, and photothermal property, provides a new strategy for circumventing multidrug resistant cancers.  相似文献   
57.
    
In a Wireless Sensor Network (WSN), coverage performance of the network is affected by multiple factors such as source power, sensitivity of sensors, and the quality of the channel between the source and the sensors. In most existing works on WSNs, only path‐loss of the wireless channel is considered, that with further assumption of absence of obstacles in the sensing region of a sensor, results in circular‐type of coverage for each node. However, in some WSN applications, the channel is not line‐of‐sight and exhibits multipath fading. In this paper, effect of the multipath fading on k‐coverage of randomly deployed WSNs is analytically investigated via techniques from stochastic geometry. More specifically, the k‐coverage probability is analytically derived under Rayleigh, Rician, and Nakagami fading assumptions. Numerical results are also presented to compare the derived k‐coverage probability with the commonly used k‐coverage models that do not consider the fading effect. These results reveal the level of the k‐coverage degradation due to multipath fading compared to the case of no fading (fixed range), which in some cases is shown to be very significant.  相似文献   
58.
    
Abstract

Food contaminants are challenging the food industry due to the inefficiency of conventional decontamination techniques. Cold plasma as an emerging technique for the degradation of food contaminants attracted notable attention. The current study overviews the plasma-induced degradation of food contaminants, discusses the mechanisms involved, points its benefits and drawbacks out, highlights the research needed in this area, and explores future trends. According to the literature, cold plasma efficiently degraded many common pesticides (e.g. parathion, paraoxon, omethoate, dichlorvos, malathion, azoxystrobin, cyprodinil, fludioxonil, cypermethrin, and chlorpyrifos) and food allergens (e.g. tropomyosin, b-conglycinin, glycinin, trypsin inhibitor, and Kunitztype trypsin inhibitor). These degradations occurred primarily due to the presence of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in the plasma that attack the chemical bonds of food contaminants. The type of pesticide degrades are highly dependent on the concentrations of plasma-generated ROS and RNS. Research showed that several parameters, such as plasma generation device, plasma exposure time, plasma power, and the carrier gas composition, influence the type and concentration of reactive species (e.g. ROS and RNS) and the overall efficiency of cold plasma degradation for a specific pesticide or allergen.
  • Highlights
  • Cold plasma can be used for degradation of many types of pesticides and allergens.

  • Plasma-generated reactive species and UV can interact with pesticides and allergens.

  • The scaled up removal of pesticides and allergens by plasma can be challenging.

  相似文献   
59.
    
In this paper, poly (vinyl pyrrolidone) (PVP) doped multiwall carbon nanotubes (MWCNTs/polyrhodanine), were synthesized through one-step chemical oxidative polymerization of rhodanine monomers on the surface-modified carbon nanotubes. Characterization of MWCNTs/polyrhodanine was conducted by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transforms infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and EDX spectrum analyses in which the results confirmed the successful formation of MWCNTs/polyrhodanine. In addition, to investigate the thermal properties of samples, thermogravimetric analysis (TGA) was employed, and results exhibited significant improvement in the nanocomposite thermal stability due to the addition of MWCNTs with reinforcement effect in polymer matrix.  相似文献   
60.
    
Clean Technologies and Environmental Policy - This paper presents a methodological approach for intelligent control of fuel cell vehicles based on traffic condition recognition. For this purpose,...  相似文献   
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