Journal of Nanotechnology最新文献

{"title":"Antibacterial Screening of Gunnera perpensa-Mediated Silver Nanoparticles","authors":"N. Patel, K. Kasumbwe, V. Mohanlall","doi":"10.1155/2020/4508543","DOIUrl":"https://doi.org/10.1155/2020/4508543","url":null,"abstract":"The biosynthesis of nanoparticles has become quite popular and has been proposed as an alternative over the tedious, expensive, and toxic physical and chemical methods of synthesis due to its cost-effectiveness and ecofriendliness. This study involved the biosynthesis, characterization, and evaluation of the antibacterial activity of Gunnera perpensa-mediated AgNPs. Biosynthesized AgNPs were characterized using TEM, UV, and FTIR spectroscopy. The antimicrobial activity was evaluated in six bacterial strains, using the disc diffusion assay, and MIC was determined using the broth dilution assay. All NPs generally presented as spherical clusters, with sizes ranging from 13 to 24 nm, as determined by TEM. The absorption peaks ranging between 421 and 425 nm and the presence of the C=O bond with amine groups, as indicated by UV and FTIR spectra, confirmed the synthesis and stabilization of G. perpensa extract-mediated AgNPs. Good antimicrobial activity ranging from 7.0 to 9.0 mm was exhibited by both preparations of G. perpensa extract-mediated AgNPs against both Gram-positive and Gram-negative studied bacteria, at MIC ranging from 3.2 to 12.5 μg/ml. Overall, good antibacterial activity was achieved at lower doses with both preparations of the G. perpensa-mediated AgNPs against all tested bacterial strains, suggesting G. perpensa-mediated AgNPs as good antimicrobial agents.","PeriodicalId":16378,"journal":{"name":"Journal of Nanotechnology","volume":"3 1","pages":"1-7"},"PeriodicalIF":4.2,"publicationDate":"2020-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84346187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simple Controlling Ecofriendly Synthesis of Silver Nanoparticles at Room Temperature Using Lemon Juice Extract and Commercial Rice Vinegar","authors":"T. Luu, X. Cao, V. T. Nguyen, N. L. Pham, H. L. Nguyen, C. Nguyen","doi":"10.1155/2020/3539701","DOIUrl":"https://doi.org/10.1155/2020/3539701","url":null,"abstract":"Silver nanoparticles were prepared in an ecofriendly manner at room temperature via the stepwise-modified Tollens route using the lemon juice extract and commercial rice vinegar. In this work, the lemon juice extract—a natural-origin chemical—was used as a reducing and stabilizing agent, and commercial rice vinegar was used to create a low acidic environment to control the silver nanoparticle growth via the stepwise method. The average dimension of silver nanoparticles was qualitatively evaluated through the UV-Vis spectra via the Mie theory. The X-ray diffraction and field emission scanning electron spectroscopy were employed to study the purity, the crystal structure, and the morphology of samples, respectively. Due to the weak activity and low purity of ecofriendly chemicals, the reaction and baking times strongly affect the preparation efficiency in obtaining small-size silver nanoparticles (∼40 nm). The highest efficiency was obtained with 24 h reaction time and 48 h baking time. The bimodal distribution of the size of silver nanoparticles was observed by UV-Vis analysis and field emission scanning electron microscopy. The obtained small-size silver nanoparticles (∼40 nm) have a uniform dimension. The quality of the obtained silver nanoparticles was evaluated through the conducting properties of silver paint made from ecosynthesized silver nanoparticles which showed a promising prospect to develop green-synthesized silver paint working at room temperature.","PeriodicalId":16378,"journal":{"name":"Journal of Nanotechnology","volume":"41 1","pages":"1-9"},"PeriodicalIF":4.2,"publicationDate":"2020-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74205076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stability Improvement of an Efficient Graphene Nanoribbon Field-Effect Transistor-Based SRAM Design","authors":"Mathan Natarajamoorthy, Jayashri Subbiah, N. Alias, M. Tan","doi":"10.1155/2020/7608279","DOIUrl":"https://doi.org/10.1155/2020/7608279","url":null,"abstract":"The development of the nanoelectronics semiconductor devices leads to the shrinking of transistors channel into nanometer dimension. However, there are obstacles that appear with downscaling of the transistors primarily various short-channel effects. Graphene nanoribbon field-effect transistor (GNRFET) is an emerging technology that can potentially solve the issues of the conventional planar MOSFET imposed by quantum mechanical (QM) effects. GNRFET can also be used as static random-access memory (SRAM) circuit design due to its remarkable electronic properties. For high-speed operation, SRAM cells are more reliable and faster to be effectively utilized as memory cache. The transistor sizing constraint affects conventional 6T SRAM in a trade-off in access and write stability. This paper investigates on the stability performance in retention, access, and write mode of 15 nm GNRFET-based 6T and 8T SRAM cells with that of 16 nm FinFET and 16 nm MOSFET. The design and simulation of the SRAM model are simulated in synopsys HSPICE. GNRFET, FinFET, and MOSFET 8T SRAM cells give better performance in static noise margin (SNM) and power consumption than 6T SRAM cells. The simulation results reveal that the GNRFET, FinFET, and MOSFET-based 8T SRAM cells improved access static noise margin considerably by 58.1%, 28%, and 20.5%, respectively, as well as average power consumption significantly by 97.27%, 99.05%, and 83.3%, respectively, to the GNRFET, FinFET, and MOSFET-based 6T SRAM design.","PeriodicalId":16378,"journal":{"name":"Journal of Nanotechnology","volume":"32 1","pages":"1-7"},"PeriodicalIF":4.2,"publicationDate":"2020-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89605246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of Growth Theory for Vapor–Liquid–Solid Nanowires: Wetting Scenario, Front Curvature, Growth Angle, Linear Tension, and Radial Instability","authors":"V. Nebol’sin, N. Swaikat, A. Y. Vorob'ev","doi":"10.1155/2020/5251823","DOIUrl":"https://doi.org/10.1155/2020/5251823","url":null,"abstract":"In this paper, we report that under wetting conditions (or modes) of nanowire (NW) growth, when a nonplanar crystallization front emerges under a catalyst droplet, a shift in the three-phase line (TPL) of the vapor–liquid–crystal interface occurs under thermodynamically stable conditions when the angle with respect to the droplet surface, termed the growth angle, is fixed. The growth angle of the NWs is determined not from a geometrical perspective but on the basis of the physical aspects of the processes occurring around the TPL, revealing a size dependence caused by the influence of linear tension of the three-phase contact of a vapor–liquid crystal. The observed radial periodic instability of the NWs is described according to the size dependence of the thermodynamic growth angle, which induces negative feedback in the system. Under the influence of linear tension and positive feedback, the tips or needles of NWs can be formed.","PeriodicalId":16378,"journal":{"name":"Journal of Nanotechnology","volume":"59 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2020-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79341172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adsorption Capacities of Hygroscopic Materials Based on NaCl-TiO2 and NaCl-SiO2 Core/Shell Particles","authors":"M. Bermeo, Nabil El Hadri, F. Ravaux, A. Zaki, L. Zou, M. Jouiad","doi":"10.1155/2020/3683629","DOIUrl":"https://doi.org/10.1155/2020/3683629","url":null,"abstract":"Hygroscopic materials which possess high moisture adsorption capacity were successfully upgraded by the functionalization of sodium chloride (NaCl) using two nuances of oxides. A procedure was developed to first prepare submicron-sized NaCl crystals; thereafter, these crystals were coated by choice of either titanium dioxide (TiO2) or silica (SiO2) to enhance the hygroscopic properties of NaCl and prevent its premature deliquescence. After coating, several analytical techniques were employed to evaluate the obtained composite materials. Our findings revealed that both composites NaCl-TiO2 and NaCl-SiO2 gave excellent performances by exhibiting interesting hydrophilic properties, compared to the sole NaCl. This was demonstrated by both environmental scanning electron microscope (ESEM) and water vapor adsorption experiments. In particular, NaCl-TiO2 composite showed the highest water adsorption capacity at low relative humidity and at a faster adsorption rate, induced by the high surface energy owing to the presence of TiO2. This result was also confirmed by the kinetics of adsorption, which revealed that not only does NaCl-TiO2 adsorb more water vapor than NaCl-SiO2 or sole NaCl but also the adsorption occurred at a much higher rate. While at room temperature and high relative humidity, the NaCl-SiO2 composite showed the best adsorption properties making it ideal to be used as a hygroscopic material, showing maximum adsorption performance compared to NaCl-TiO2 or sole NaCl. Therefore, NaCl-TiO2 and NaCl-SiO2 composites could be considered as promising hygroscopic materials and potential candidates to replace the existing salt seeding agents.","PeriodicalId":16378,"journal":{"name":"Journal of Nanotechnology","volume":"10 1","pages":"1-16"},"PeriodicalIF":4.2,"publicationDate":"2020-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89385472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Highly Efficient Photocatalysis by Zinc Oxide-Reduced Graphene Oxide (ZnO-rGO) Composite Synthesized via One-Pot Room-Temperature Chemical Deposition Method","authors":"Roselle T. Ngaloy, A. Fontanilla, Ma. S. Rebecca Soriano, C. Pascua, Y. Matsushita, I. Agulo","doi":"10.1155/2019/1895043","DOIUrl":"https://doi.org/10.1155/2019/1895043","url":null,"abstract":"We synthesized zinc oxide-reduced graphene oxide (ZnO-rGO) composites using a one-pot chemical deposition method at room temperature. Zinc powder and graphene oxide (GO) of different mass ratios (1 : 1, 1 : 2, 1 : 5, 1 : 10, and 1 : 20 GO to Zn) were used as precursors in a mildly alkaline solution. UV-Vis spectroscopy was used to study the photocatalytic efficiency of the samples through the photodegradation of methylene blue (MB). UV-Vis measurements show the fast decomposition of methylene blue under UV light illumination with the best degradation efficiency of 97.7% within one hour, achieved with sample ZG2 (1 GO : 2 Zn mass ratio). The corresponding degradation rate was kZG2 = 0.1253 min−1, which is at least 5.5 times better than other existing works using hydrothermal methods. We argue that the excellent photodegradation of MB by ZG2 is due to the efficient charge separation brought about by the electronic interaction of the rGO with the ZnO and the formation of a Zn-O-C bond, as supported by XRD and Raman spectroscopy measurements.","PeriodicalId":16378,"journal":{"name":"Journal of Nanotechnology","volume":"3 1","pages":"1-11"},"PeriodicalIF":4.2,"publicationDate":"2019-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90160915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Magnetite nanoparticles for reduction of hexavalent chrome in soil of an industrial park, Cerro Colorado - Arequipa [Nanopartículas de magnetita para reducción de cromo hexavalente en suelo de un parque industrial, Cerro Colorado – Arequipa]","authors":"Mardelly Ruiz Marcelo, Cecilia Cermeño Castromonte, Elmer Benites Alfaro","doi":"10.32829/nanoj.v3i1.101","DOIUrl":"https://doi.org/10.32829/nanoj.v3i1.101","url":null,"abstract":"One of the most important contamination problems in receiving bodies due to industrial activities is the presence of chromium (VI). One way to reduce the aggressiveness of said contaminant is its reduction to the form of chromium (III). The investigation determined the efficiency of magnetite nanoparticles in the treatment of soil contaminating with chromium (VI), to reduce it to chromium (III) of an Industrial Park at the district Cerro Colorado, province and department of Arequipa. 22 samples of 1 kg of soil were taken, then homogenized according to the extraction distances, considering at the end only 3 samples called “Shore”, “6 Meters” and “9 Meters”, whose concentrations were: 146 mg / kg, 126 mg / kg and 67 mg / kg of Cr (VI) respectively. These samples were subjected to 3 treatments (T1, T2 and T3) with 3 repetitions each using 15, Please cite this article as: Ruiz M., Cermeño C., Benites E., Magnetite nanoparticles for reduction of hexavalent chrome in soil of an industrial park, Cerro Colorado Arequipa, Journal of Nanotechnology, vol. 3, no 1, 2019, pp. 12-17. https://doi.org/10.32829/nanoj.v3i1.101 A publication of Nanoj CINCADER Centre of Research and Training for Regional Development Online at www.journals.cincader.org Journal of Nanotechnology Vol. 3, N° 1, 2019 Copyright © 2019, CINCADER. ISSN 2522-6908 DOI: https://doi.org/10.32829/nanoj.v3i1.101 13 30 and 45 grams doses of Magnetite nanoparticles for three weeks. At the end of the treatment using the EPA 3060 method, the Chrome (VI) analysis was performed. The 3 treatments “T1”, “T2” and “T3”, had significant differences for the final concentrations of Hexavalent Chromium in the soil; but it was in Treatment 3 in the soil samples \"Shore\", \"6 Meters\" and \"9 Meters\", where a greater effect was achieved in the reduction of Cr (VI) to Chromium (III) with an efficiency of 99.96%, 99.93% and 99.93% respectively, 45 grams of magnetite nanoparticles were used for this treatment.","PeriodicalId":16378,"journal":{"name":"Journal of Nanotechnology","volume":"2012 1","pages":"12"},"PeriodicalIF":4.2,"publicationDate":"2019-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88147113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermoelectric Effect of Buckypaper/Copper Assembly","authors":"P. Pinheiro, Luiza Ferreira, Fabrício Rodrigues, J. C. Oliveira, Anselmo F R Rodriguez, M. Sousa, M. Reis","doi":"10.1155/2019/8385091","DOIUrl":"https://doi.org/10.1155/2019/8385091","url":null,"abstract":"Carbon nanotubes (CNTs) exhibit excellent electrical and thermal properties that have been used in several device assemblies, such as electrode sheets made from an aggregate of CNTs, also called as buckypaper (BP). Despite that, the properties of single CNTs are reduced when randomly assembled to form a BP. In this way, this study investigated the thermoelectric effect of a BP electrode assembled on a copper electrode with an active area of 4.0 cm2. The micrographs were obtained by scanning electron microscopy and show morphology agglomerated of multiwalled CNTs, which permeated into the filter paper, forming a thickness of 67.33 μm. Moreover, indoor/outdoor tests were performed approaching the BP electrode from a heat source. Thus, the electrical responses in function of temperature variation show maximum thermovoltages of 9.0 mV and 40.73 mV from indoor and outdoor tests, respectively. Finally, an average Seebeck coefficient for the BP/copper electrodes array of 35.34 ± 6.0 mV/K was estimated from 298 to 304 K. These findings suggest that this assembly will be easily applied in thermoelectric device concepts.","PeriodicalId":16378,"journal":{"name":"Journal of Nanotechnology","volume":"111 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2019-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81648254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analytical Electron Microscopy of Silicon Nitride Nanostructures Synthesized from the Vapor Phase","authors":"Mariella Cortez Caillahua, F. J. Moura, G. Solórzano","doi":"10.32829/nanoj.v3i1.87","DOIUrl":"https://doi.org/10.32829/nanoj.v3i1.87","url":null,"abstract":"Silicon nitride, Si3N4 is a covalent compound with excellent physical and chemical properties such as corrosion resistance, low-specific weight and good thermal conductivity at ambient and elevated temperatures. Such properties are very attractive in application as advanced ceramics and in semiconductor devise [1]. Nano sized amorphous silicon nitride powders were synthesized at 300 °C by precipitation from the vapor phase reaction of SiCl4 and NH3 and Ar as carrier gas. Solid ammonium halogenide is formed as by-product, in addition to silicon nitride powder.","PeriodicalId":16378,"journal":{"name":"Journal of Nanotechnology","volume":"41 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2019-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73728840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Micro/Nanofabrication and Characterization of Advanced Materials and Devices","authors":"Yanxi Li, Liang He, Mengyu Yan, Zhengjun Wang","doi":"10.1155/2019/5032747","DOIUrl":"https://doi.org/10.1155/2019/5032747","url":null,"abstract":"Department of Materials Science and Engineering, Virginia Tech, Blacksburg, VA 24061, USA State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China Department of Materials Science and Engineering, University of Washington, Seattle, WA 98195, USA Department of Physics and Astronomy, West Virginia University, Morgantown, WV 26506, USA","PeriodicalId":16378,"journal":{"name":"Journal of Nanotechnology","volume":"7 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2019-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73665521","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}