In this article, the effects of two inorganic corrosion inhibitors, permanganate and phosphate anions, on morphology, composition, thickness, and corrosion resistance of the anodic film formed on 2024 aluminum alloy in sulfuric acid were investigated. Surface morphology of the oxide films were studied by field emission scanning electron microscopy. Electrochemical impedance spectroscopy and potentiodynamic polarization tests were conducted to assess the corrosion resistance of the coatings. These analyses showed that the presence of the mentioned inhibitors changed the coating morphology, especially in the case of phosphate ions. Corrosion results indicated that using inhibitors during the anodizing process increased the corrosion resistance of the anodized samples. The increases were approximately 81% and 97% for 0.05 M of permanganate and phosphate ions, respectively, compared with the anodized coatings in the absence of additives. An increase in the inhibitor concentration results in better corrosion resistance of the aluminum anodic layer. 相似文献
The rapid progression in biomaterial nanotechnology apprehends the potential of non-toxic and potent polysaccharide delivery modules to overcome oral chemotherapeutic challenges. The present study is aimed to design, fabricate and characterize polysaccharide nanoparticles for methotrexate (MTX) delivery. The nanoparticles (NPs) were prepared by Abelmoschus esculentus mucilage (AEM) and chitosan (CS) by the modified coacervation method, followed by ultra-sonification. The NPs showed much better pharmaceutical properties with a spherical shape and smooth surface of 213.4–254.2 nm with PDI ranging between 0.279–0.485 size with entrapment efficiency varying from 42.08 ± 1.2 to 72.23 ± 2.0. The results revealed NPs to possess positive zeta potential and a low polydispersity index (PDI). The in-vitro drug release showed a sustained release of the drug up to 32 h with pH-dependence. Blank AEM -CS NPs showed no in-vivo toxicity for a time duration of 14 days, accompanied by high cytotoxic effects of optimized MTX loaded NPs against MCF-7 and MD-MBA231 cells by MTT assay. In conclusion, the findings advocated the therapeutic potential of AEM/CS NPs as an efficacious tool, offering a new perspective for pH-responsive routing of anticancer drugs with tumor cells as a target. 相似文献
We have investigated the 20 nm p-type double gate junctionless tunnel field effect transistor (P-DGJLTFET) and the impact of variation of different device parameters on the performance parameters of the P-DGJLTFET is discussed. We achieved excellent results of different performance parameters by taking the optimized device parameters of the P-DGJLTFET. Together with a high-k dielectric material (TiO2) of 20 nm gate length, the simulation results of the P-DGJLTFET show excellent characteristics with a high IoN of ~ 0.3 mA/μm, a low/OFF of ~ 30 fA/μm, a high ION/IOFF ratio of ~ 1×10^10, a subthreshold slope (SS) point of ~ 23 mV/decade, and an average SS of ~ 49 mV/decade at a supply voltage of -1 V and at room temperature, which indicates that PDGJLTFET is a promising candidate for sub-22 nm technology nodes in the implementation of integrated circuits. 相似文献
In this article, a novel planar helix traveling wave tube structure is proposed for S/X-band amplification. The planar helix structure is developed between two printed circuit boards such that they utilize solder balls to connect each other. This technique which comes originally from microelecronic packaging technology called ball grid array. To evaluate the performance of the proposed structure, one period of its geometry is modeled and the cold test parameters are calculated in CST microwave studioTM. The fundamental space harmonic mode overlaps well with the beam-line in the dispersion diagram for both bands. The in- and out-coupler ports are also designed in the form of coplanar waveguides having good matching. For 150 periods of the planar helix, the 15 dB gain is obtained in particle-in-cell simulations for both bands. Finally, the fabrication process is implemented and the cold test is done.
Silicon - In this paper influences of uniform and non-uniform doping on the performance of SOI and SELBOX FinFET at gate length of sub-7 nm are evaluated. Junctionless devices require very... 相似文献
The aim of this study was to synthesize Hydroxyapatite (HA) from carp bone waste by calcination treatment. The effects of calcination temperature and time on crystallite size, crystallinity%, powder size and morphology, formed phases, and Ca/P ratio were analyzed. The XRD analyses indicated that for 1 h calcination time, HA was the only phase produced at all temperatures. However, for 5 h calcination time, temperatures other than 700ºC resulted in formation of TCP+HA. The HA obtained at 700ºC at both times had less crystallinity compared to other temperatures. Crystallite size increased by increase in temperature at 1 h calcination time. The smallest and largest particulate sizes were obtained at 800ºC for 1 h and 900ºC for 5 h, respectively. The Ca/P ratio close to theoretical value (1.67) was obtained for 5 h calcination time. Finally, the results showed the usefulness of the methodology used in natural HA production that can be used in orthopedics and dentistry. 相似文献
The multimode orbital angular momentum (OAM) radio waves can be used to multiplex multiple transmission channels to increase the capacity of communication system without adding additional bandwidth. However, the divergence of the OAM beams and beam inconsistency escalate by increasing OAM mode number. Moreover, the worse sidelobe level (SLL) always appears along with a better convergent beam. In this article, the fruit fly optimization algorithm (FOA) is proposed to suppress the SLL in multimode OAM scenario. Based on the concentric circular array antenna (CCAA), the feeding amplitudes and the radii of the array are synthesized simultaneously to realize less than ?30 dB SLL of the multimode OAM patterns. When the main lobes with different OAM modes steered to a uniform azimuth of θ = 0° , the SLLs of these OAM modes are also suppressed to less than ?21 dB. The advantages of FOA used in the OAM pattern synthesis are verified by comparing it with the genetic algorithm (GA). The FOA‐based synthesis has a simpler implementation flow diagram which reduces the time of synthesis to 39.5% of GA. 相似文献
This review highlights a number of recent discoveries and advances in the construction of carbon-sulfur bonds through decarboxylative cross-coupling reactions between carboxylic acids and sulfur-containing coupling partners. Particular emphasis is placed on the mechanistic aspects of the reactions. 相似文献
Multimedia Tools and Applications - The smile is one of the most common human facial expressions encountered in our daily lives. Smile recognition can be used in many scenarios, such as emotion... 相似文献