فهرست مطالب

Journal of Nanoanalysis
Volume:7 Issue: 3, Sep 2020

  • تاریخ انتشار: 1399/06/11
  • تعداد عناوین: 7
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  • Hassan Gheisari *, Ebrahim Karamian, Ali Soheily Pages 166-178
    In this study, Merwinite (MW), has been successfully prepared by a modifiedsol-gel method. Optimization in calcination temperature and mechanical millingresulted in a pure and nano-sized powder which characterized by means of(XRD), (SEM), (TEM) and (FT–IR). We hypothesized that nano-sized MW wouldmimic more efficiently the nanocrystal structure and function of natural boneapatite, owing to the higher surface area, compared to conventional micronsizeMW. Mechanical grinding in a ceramic ball mill for 6 hours resulted in (MW)nanoparticles in the range of about 33- 55 nm. Conventional micron-size MWhad been previously investigated by many researchers but it is obviously differentfrom bone mineral in aspect of mimicking the mineral resorption process. Bonecrystals of natural hydroxyapatite (NHA ) are in nano-size dimensions and possessvery large surface area. In contrast micron-size particles with lower surface arealack the potency of homogeneous absorption by osteoclasts and miss the uniqueadvantage of nanotechnology for bioactivity and resorbability. Hence, we usedthe unique advantage of nano- biotechnology to improve novel nano merwinite(NMW) particles as a good candidate for tissue regeneration whether as a peri -implant filling powder or in combination with other biomaterials as a compositescaffold.
    Keywords: merwinite, Nano bioceramic powder, Transmition Electron, Microscopy
  • Babak Azari, Afshin Pourahmad *, Babak Sadeghi, Masoud Mokhtary Pages 179-189
    White rice husk ash (RHA), an agricultural waste, was used as a silica source forMTW zeolite synthesis. The RHA-MTW zeolite derived from RHA was preparedby hydrothermal method at 150 °C in the presence of tetraethylammoniumhydroxide. ZnO nanoparticles (NPs) were grown in zeolite substrates using asolid state reaction. The synthesized nanocomposite (NC) was characterized byXRD, SEM, DRS and TEM and tested as photocatalytic degradation of methyleneblue (MB) dye from aqueous solution under ultraviolet (UV) light. The BET resultsindicated that pore volume and surface area of ZnO/RHA-MTW NC was smallerthan RHA-MTW zeolite. On the basis of the obtained experimental results, it wasfound that zinc oxide NPs were encapsulated into the channels of RHA-MTWzeolite. The SEM and TEM images of ZnO/RHA-MTW NC confirmed the formationof RHA-MTW particles with size diameter of 2.5 μm and locating of zinc oxideNPs in channels of zeolite with an average size of between 35 nm. The resultsshowed MB degradation had reached 85 % under UV light. The MB indicatedmaximum adsorption at pH=9. The photocatalytic activity of ZnO was enhancedin the presence of zeolite due to reduction of recombination rate of the electrohole in ZnO semiconductor.ARTICLE INF O
    Keywords: Environmental Catalysis, green chemistry, Photocatalysis, Nanoporous materials, nanocomposites
  • Fayzollah Khorramrouz, Seyed Ali Sedigh Ziabari *, Ali Heydari Pages 190-199
    In this paper, we propose an innovative and low computational cost approachthat can be used to find optimal values of parameters of a nanoscale dual gatetunneling field-effect transistor (DG-TFET). In this way, after obtaining analyticalexpressions for potential and energy bands of the device using the Poissonequation, the tunneling length is extracted at source-channel and channel-draintunnel junctions in the AMBIPOLAR, Off and On states. Due to the tunnelinglength equation, the different values of gate work function and dielectric constantof the device are swept to determine the minimum and maximum designlimits. According to the above range, the necessary checks are made to reachthe local optimal behaviors. These optimum points are explained based on theachievement of optimal device performance. The accuracy and consistency ofthe proposed model are validated with the TCAD simulation results. The presentmodel can be a handful for the study of TFET performance.
    Keywords: 2D Analytical model, Surface potential, BTBT, minimum tunneling length, DG-TFET
  • Zaccheus Shehu *, Yakong David, Danbature Lamayi, Mela Yoro, Sani Aliyu Pages 200-205
    MgO@SiO2 nanocomposite was synthesized using mechanochemical method andits formation was confirmed by FTIR and Uv-visible spectroscopic techniques.The antibacterial effect of MgO@SiO2 nanocomposite was carried out on bacterialisolates; gram-positive bacteria (Bacillus subtilis, Klebsiella pneunoniae) and gramnegative bacteria (Pseudomonas aeruginasa, Escherichia coli, and Salmonella typhi) using Agar well diffusion method. The results showed that MgO@SiO2 nanocomposite can find application as antibiotics against the investigated microbes.
    Keywords: MgO@SiO2, nanocomposite, Mechanosynthesis, Antibacterial activity, Solvent-free
  • F. Mirjalili *, F. Danafar, A. Zarei Mahmodabadi Pages 206-215
    Alumina nano fibers were produced using a combined method of sol-gel andelectros pinning method. The sol was first prepared by mixing of tri-isoproxidealuminum in aqueous solution of nitric acid. In the next step, ethylene glycol,acid lactic and poly vinyl alcohol were added to the solution .Finally, the sol wasthen heated at 80 °C to obtain gel. The resulting gel was converted to nano fibersof aluminum oxide by electrospinning method. The nano fibers were dried at60 °C for 24 h and sintered at 1200 °C for 2 h. The results of XRD and FTIRshowed that, in all samples the dominant phase was the corundum phase. Todecrease the sintering temperature, magnesium nitrate hexahydrate (MgN2O6 *6H2O) and sodium ethoxylate (SiC8 H2o O4) were added to the sol containing10% Polyvinyl alcohol. The XRD and FTIR analysis of this sample indicated thepresence of corundum phase when the sintering temperature of 1000°C was used. Accordingly, the energy consumption was reduced as the sintering temperaturedecreased about 200°C by adding the additives. The SEM and TEM analysis alsoshowed formation of non-agglomerated nano fibers with diameters of 41nmwhen 10% polyvinyl alcohol and 2% sodium ethoxylate (SiC8 H20 O4) was addedto the sol.
    Keywords: Nano alumina fiber, Sol-gel method, Electrospinning
  • Hayrunnisa Nadaroglu *, Azize Alaylı, Selçuk Çeker, Hatice Ogutcu, Guleray Agar Pages 216-224
    It is seen that metal nanoparticles are used in many areas due to their antimicrobialeffects. For this reason, our study focused on the production of a-Fe2O3, NiOand CoO NPs of golden nanoparticles, which are easily obtained with the use ofErzincan grape extract, safe to use, environmentally friendly and cost-effective.Metal ions synthesized by the green synthesis method were characterized usingthe Scanning Electron Microscope (SEM) analysis. From the SEM diagrams ofthe synthesized nanoparticles, it was determined that the nanoparticles wereapproximately 5 to 65 nm in size. Both antimicrobial, genotoxicity and cytotoxicity effects were investigated to determine the rates at which nanoparticles can be used as biosafe. Synthesized a-Fe2O3, NiO and CoO NPs showed excellent antibacterial properties on pathogen bacteria against human. In addition, it was determined that a-Fe2O3, NiO and CoO M-NPs showed genotoxic properties in parallel with increasing concentrations. This study, as far as we know, is the first report on microbial a-Fe2O3, NiO and CoO NPs and their biological properties synthesized by this statistical approach.
    Keywords: a-Fe2O3, NiO, CoO NPs, Green synthesis, Antimicrobial Activity, Genotoxic effect, Pathogen microorganisms
  • Hassan Gheisari, Ebrahim Karamian, Ali Soheily Pages 225-229

    In this study, Merwinite (MW), has been successfully prepared by a modifiedsol-gel method. Optimization in calcination temperature and mechanical millingresulted in a pure and nano-sized powder which characterized by means of(XRD), (SEM), (TEM) and (FT–IR). We hypothesized that nano-sized MW wouldmimic more efficiently the nanocrystal structure and function of natural boneapatite, owing to the higher surface area, compared to conventional micronsizeMW. Mechanical grinding in a ceramic ball mill for 6 hours resulted in (MW)nanoparticles in the range of about 33- 55 nm. Conventional micron-size MWhad been previously investigated by many researchers but it is obviously differentfrom bone mineral in aspect of mimicking the mineral resorption process. Bonecrystals of natural hydroxyapatite (NHA ) are in nano-size dimensions and possessvery large surface area. In contrast micron-size particles with lower surface arealack the potency of homogeneous absorption by osteoclasts and miss the uniqueadvantage of nanotechnology for bioactivity and resorbability. Hence, we usedthe unique advantage of nano- biotechnology to improve novel nano merwinite(NMW) particles as a good candidate for tissue regeneration whether as a peri -implant filling powder or in combination with other biomaterials as a compositescaffold.

    Keywords: merwinite, Nano bioceramic powder, Transmition Electron, Microscopy