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641.
Food Science and Biotechnology - The free and bound phenolic constituents in Dendrocalamus hamiltonii shoots were evaluated and compared to processed bamboo candy. Preliminary proximate analysis...  相似文献   
642.
The complex structured starch particles were reduced to the nanoscale size range through hydrolysis utilizing low concentration acid assisted by ultrasound irradiation. The synthesized starch nanoparticles (SNPs) were characterized by transmission electron microscopy (TEM), Fourier-transform infrared (FTIR), and X-ray diffraction (XRD) techniques. The synthesized SNPs possessed surface activated entities, as many cationic functional groups were confirmed through the FTIR spectrum. Also, these SNPs were effectively utilized to separate heavy Cu metal ions from the synthetic ion solution. The SNPs were characterized using field emission scanning electron microscope (FESEM), X-ray photoelectron spectroscopy (XPS), and Brunauer–Emmett–Teller (BET) analysis for the surface modification after the adsorption process. The weak electrostatic interaction between the SNP surface and Cu ion was confirmed by the XPS spectrum and energy-dispersive X-ray spectroscopy. The maximum efficiency of Cu ions removal was about 93% at an optimal pH 5 and 25 mg/ml dosage. The adsorption equilibrium was obtained in 60 min. The nitrogen isotherm BET analysis of SNPs after adsorption shows a higher specific surface area of 18.552 m2/g, attributed to the interaction and presence of Cu ions on the SNP surface. The process feasibility was validated by the Langmuir isotherm model. The process exhibits pseudo-second-order adsorption kinetics and follows the Langmuir isotherm. The RL predicted by the Langmuir isotherm mechanism is 0.017, implying favourable adsorption. The process is reproducible and allows for the separation of heavy metal ions from the wastewater through biosorption effectively.  相似文献   
643.
Lithium-air batteries based on CO2 reactant (Li–CO2) have recently been of interest because it has been found that reversible Li/CO2 electrochemistry is feasible. In this study, a new medium-entropy cathode catalyst, (NbTa)0.5BiS3, that enables the reversible electrochemistry to operate at high rates is presented. This medium entropy cathode catalyst is combined with an ionic liquid-based electrolyte blend to give a Li–CO2 battery that operates at high current density of 5000 mA g−1 and capacity of 5000 mAh g−1 for up to 125 cycles, far exceeding reported values in the literature for this type of battery. The higher rate performance is believed to be due to the greater stability of the multi-element (NbTa)0.5BiS3 catalyst because of its higher entropy compared to previously used catalysts with a smaller number of elements with lower entropies. Evidence for this comes from computational studies giving very low surface energies (high surface stability) for (NbTa)0.5BiS3 and transmission electron microscopystudies showing the structure being retained after cycling. In addition, the calculations indicate that Nb-terminated surface promotes Li–CO2 electrochemistry resulting in Li2CO3 and carbon formation, consistent with the products found in the cell. These results open new direction to design and develop high-performance Li–CO2 batteries.  相似文献   
644.
Kashyap  Vikas  Kumar  Chandra  Chaudhary  Neeru  Saxena  Kapil 《SILICON》2023,15(3):1203-1210
Silicon - In the present paper, we report the observations of field emission (FE) from silicon nanowires array (Si-NWsA) synthesized on p-type Si (100) using wet chemical etching (WCE) approach,...  相似文献   
645.
Journal of Inorganic and Organometallic Polymers and Materials - Current study delineates the synthesis and environmental applications of ZnO/CuO nanocomposite in photocatalysis and gas sensing....  相似文献   
646.
Mishra  Varun  Verma  Yogesh Kumar  Gupta  Santosh Kumar  Rathi  Vikas 《SILICON》2022,14(5):2275-2282
Silicon - In this article, a distinctive charge plasma (CP) technique is employed to design two doping-less dual gate tunnel field effect transistors (DL-DG-TFETs) with Si0.5Ge0.5 and Si as source...  相似文献   
647.
Pasting properties of ten Thai rice varieties, with amylose contents in the range of 16 to 33% and stored at 10, 30 and 40 °C for six months were compared using the Brabender Viscoamylograph (VAG) and the Rapid Visco Analyser (RVA) for evaluating the texture of cooked rice. Linear correlations between pasting temperature and viscosity parameters based on RVA showed a different pattern than those based on VAG with high negative correlation coefficients between the peak and breakdown viscosities. Both RVA and VAG indicated peak viscosity to be positively correlated with breakdown viscosity, and negatively with the setback viscosity. Setback and consistency viscosities correlated with each other in both instruments but indicating a negative correlation with breakdown viscosity in VAG only. Pasting temperature determined by VAG and RVA did not show good correlations for rice sample stored at different temperatures neither for individual nor for combined data. Only peak, breakdown and setback viscosities showed significant correlations in the overall data (r > 0.496). The VAG measurements performed better than the RVA in the development of predictive models for evaluating the hardness and adhesiveness of cooked rice based on instrumental texture profile analysis. The springiness and cohesiveness of cooked rice could not be estimated from the pasting properties of rice flour determined by both VAG and RVA. Results showed that both VAG and RVA could be used for evaluating the texture of cooked rice despite the differences in the measurements of the pasting properties of milled rice flours.  相似文献   
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