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1.
Catalysis Letters - We converted agro-waste Custard Apple Peels (CAP) to ash via thermal treatment, on which Pd(OAc)2 was immobilized easily that produced a low-cost, highly efficient Pd/CAP-ash...  相似文献   
2.
Wireless Personal Communications - This research work explores the neural network learning capabilities by using a multi-layer perceptron artificial neural network to predict signal power loss by...  相似文献   
3.
Na1/2Bi1/2TiO3-based materials have been earmarked for one of the first large-volume applications of lead-free piezoceramics in high-power ultrasonics. Zn2+-doping is demonstrated as a viable route to enhance the thermal depolarization temperature and electromechanically harden (1-y)Na1/2Bi1/2TiO3-yBaTiO3 (NBT100yBT) with a maximum achievable operating temperature of 150 °C and mechanical quality factor of 627 for 1 mole % Zn2+-doped NBT6BT. Although quenching from sintering temperatures has been recently touted to enhance TF-R, with quenching the doped compositions featuring an additional increase in TF-R by 17 °C, it exhibits negligible effect on the electromechanical properties. The effect is rationalized considering the missing influence on conductivity and therefore, negligible changes in the defect chemistry upon quenching. High-resolution diffraction indicates that Zn2+-doped samples favor the tetragonal phase with enhanced lattice distortion, further corroborated by 23Na Nuclear Magnetic Resonance investigations.  相似文献   
4.
The interactions of amino acids and peptides at model membrane interfaces have considerable implications for biological functions, with the ability to act as chemical messengers, hormones, neurotransmitters, and even as antibiotics and anticancer agents. In this study, glycine and the short glycine peptides diglycine, triglycine, and tetraglycine are studied with regards to their interactions at the model membrane interface of Aerosol-OT (AOT) reverse micelles via 1H NMR spectroscopy, dynamic light scattering (DLS), and Langmuir trough measurements. It was found that with the exception of monomeric glycine, the peptides prefer to associate between the interface and bulk water pool of the reverse micelle. Monomeric glycine, however, resides with the N-terminus in the ordered interstitial water (stern layer) and the C-terminus located in the bulk water pool of the reverse micelle.  相似文献   
5.
Mobile Networks and Applications - Blockchain applications have continuously improved ever since its first debut on cryptocurrency. From then on, its uses have branched out from the financial...  相似文献   
6.
The extensive occurrence of textile and pharmaceutical contaminants and their metabolites in water systems has posed significant concerns regarding their possible threat to human health and the environmental system. As a result, herein ZnFe2O4 nanoparticles were synthesized through the use of Monsonia burkeana plant extract. The synthesized nanoparticles were characterized using XRD, FTIR, UV–vis, SEM, EDS, TGA, BET, PL, EPR and VSM. XRD showed that the crystalline structure of ZnFe2O4 nanoparticles with a calculated crystal size of 25.03 nm was formed. FT-IR confirmed the characteristic functional groups contained within the M. burkeana plant were deposited on the formed ferrite nanoparticles. BET analysis confirmed the mesoporous nature of ZnFe2O4 with an average pore diameter of 31.6 nm. Morphological studies demonstrated that the formed nanoparticles had spherical as well as rod-like shapes. ZnFe2O4 photocatalyst illustrated that it may be effortlessly detached by an external magnetic field. The optimum conditions for the 99.8% removal of Methylene Blue was obtained at pH12, within 45min and at the optimum dosage of 25 mg of the catalyst. The as-prepared ZnFe2O4 nanoparticles proved to be easily separated and recycled, and remained efficient even after 5 reuses, proving that the material is highly stable. The ROS studies also demonstrated that electrons are the main factors contributing to the degradation of MB. Upon testing the photocatalytic performance of the sulfonamide antibiotic, sulfisoxazole in water showed a degradation of 67%. This study has shown that these materials can be used in targeting textile and pharmaceutically polluted water.  相似文献   
7.
This work presents the dielectric properties of YNbO4 (YNO)–TiO2 composites in the microwave range. X-ray diffraction analysis demonstrates that the addition of TiO2 to YNO results in the formation of a Y(Nb0.5Ti0.5)2O6 phase. In the microwave range, the values of permittivity and dielectric loss did not present major changes with the increment of TiO2. Moreover, the addition of TiO2 results in an improvement in the thermal stability of YNO, with YNO63 demonstrating a resonant frequency of ?8.96 ppm.°C?1. We utilised numerical simulations to evaluate the behaviour of these materials as dielectric resonator antennae and it is found that they exhibit a reflection coefficient below ?10 dB at the resonant frequency, with a realised gain of 4.94 – 5.76 dBi, a bandwidth of 665–1050 MHz and a radiation efficiency above 84%. Our results indicate that YNO–TiO2 composites are interesting candidates for microwave operating devices.  相似文献   
8.
Journal of Chemical Ecology - Entomopathogenic fungi (EPF) can be experimentally established in several plant species as endophytes. Ecological effects of EPF inoculations on plant growth and...  相似文献   
9.
In this study, La was doped into the lithium layer of Li-rich cathode material and formed a layered-spinel hetero-structure. The morphology, crystal structure, element valence and kinetics of lithium ion migration were studied by field emission scanning electron microscope (FESEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and electrochemical impedance spectroscopy (EIS). The La doped lithium-rich cathode material exhibited similar initial discharge capacity of 262.8 mAh g?1 at 0.1 C compared with the undoped material, but the discharge capacity retention rate can be obviously improved to 90% after 50 cycles at 1.0 C. Besides that, much better rate capability and Li+ diffusion coefficient were observed. The results revealed that La doping not only stabilized the material structure and reduced the Li/Ni mixing degree, but also induced the generation of spinel phase to provide three-dimensional diffusion channels for lithium ion migration. Moreover, the porous structure of the doped samples also contributed to the remarkable excellent electrochemical performance. All of these factors combined to significantly improve the electrochemical performance of the material.  相似文献   
10.
The uniform refinement mechanisms and methods of deformed mixed and coarse grains inside a solution-treatment Ni-based superalloy during two-stage annealing treatment have been investigated.The two-stage heat treatment experiments include an aging annealing treatment(AT)and a subsequent recrystallization annealing treatment(RT).The object of AT is to precipitate some δ phases and consume part of storage energy to inhibit the grain growth during RT,while the RT is to refine mixed and coarse grains by recrystallization.It can be found that the recrystallization grains will quickly grow up to a large size when the AT time is too low or the RT temperature is too high,while the deformed coarse grains cannot be eliminated when the AT time is too long or the RT temperature is too low.In addition,the mixed microstructure composed of some abnormal coarse recrystallization grains(ACRGs)and a large number of fine grains can be observed in the annealed specimen when the AT time is 3 h and RT tem-perature is 980℃.The phenomenon attributes to the uneven distribution of δ phase resulted from the heterogeneous deformation energy when the AT time is too short.In the regions with a large number of δ phases,the recrystallization nucleation rate is promoted and the growth of grains is limited,which results in fine grains.However,in the regions with few δ phases,the recrystallization grains around grain boundaries can easily grow up,and the new recrystallization nucleus is difficult to form inside grain,which leads to ACRGs.Thus,in order to obtain uniform and fine annealed microstructure,it is a prereq-uisite to precipitate even-distributed δ phase by choosing a suitable AT time,such as 12 h.Moreover,a relative high RT temperature is also needed to promote the recrystallization nucleation around δ phase.The optimal annealing parameters range for uniformly refining mixed crystal can be summarized as:900℃×12 h+990℃×(40-60 min)and 900℃×12 h+1000℃×(10-15 min).  相似文献   
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