Journal of Nanoanalysis
Volume:8 Issue: 2, Jun 2021

In this study, highly porous almost (75%) nanostructured Hardystonite/biphasic calcium phosphate scaffolds (BCPS) with interconnected porosity were developed using various hardystonite (HT) contents via space holder technique. Transmission electron microscopy (TEM), X-ray diffraction (XRD), and scanning electron microscopy (SEM) techniques were employed to evaluate different samples. Inaddition, the agents of scaffold composition of mechanical behavior, bioactivity, and biodegradability were studied. Also, the results showed that the produced scaffolds had an average pore size and density between 250-350 μm and 2.2 ± 0.4 - 1.7 ± 0.2 gr/cm3, respectively, depending on the Hardystonite (HT) with different contents. Furthermore, increasing the hardystonite content of scaffolds from 0 (control) to 30 wt. % enhanced the bioactivity test, biodegradability, and compressive strength from 1.1 ± 0.1 to 3.1 ± 0.2 MPa, respectively. Besides, MTT assay also confirmed that the BCPS30 (containing 30 wt. % of hardystonite) significantly promoted cell viability and cell adhesion compared to BCPS 0. Totally, our project suggests that nanostructured hardystonite/BCPS with improved biological and mechanical behavior (properties) could potentially be used for biomedical engineering such as bone tissue engineering applications.

A novel metal-organic framework (MOF), with the formula [Cu(II)L]n (L= 4, 4′-diamino diphenyl sulfone), has been synthesized conventionally and hydrothermally methods and characterized by FT-IR, PXRD, EDX, and SEM techniques. The results MOFs were applied for photodegradation of MethyleneBlue (MB). The influence of affecting variables, such as initial MB dye concentration (2–8mg L−1), Cu(II)-MOF mass (0.01–0.03 mg), pH (3.0–9.0), and time of irradiation (30–90 min). The photocatalytic degradation efficiency was investigated by the central composite design (CCD) methodology. The results of CCD analysis for optimum values of variables revealed that Cu(II)-MOF mass was 0.025g, theinitial concentration of MB was 3.51 mg L−1, pH was 4.50, and irradiation time was 75 min. Under the optimum conditions, the photocatalytic MB degradation percentage at the desirability function value of 1.0 was found to be 70%. In addition, the obtained R2 value of 0.97 in the regression analysis showed a high photocatalytic efficiency of the proposed method for MB degradation.

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-gatea tunneling 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 of theproposed model are validated with the TCAD simulation results. The present modelcan be a handful for the study of TFET performance.

Using mineral admixtures in cement composites as a way to improve their mechanical and durability properties is a common practice in concrete technology. Among them, silica fume and nano-silica effectively influence the composite's early and long-term properties. Due to the limited particle size distribution of nano and micro-silica, it is expected that the incorporation of some mineraladditives with a size greater than 500 nm may result in better mechanical and durability performance because of the filler effect. In this study, the effect of different percentages of TiO2 on the mechanical properties of cement composites containing nano-silica and silica fume was investigated. Six designs were tested for compressive strength with respect to zero, 2.5, and 5 percent replacementof cement with TiO2. The addition of TiO2 has led to an increase in compressive strength. The best results from the sample with 2.5% TiO2 are obtained. This could be due to the effect of TiO2 particles filling. Comparison of SF3, SF2, and SF1 at 28 days of age showed that SF2 increased the compressive strength. This shows that TiO2 has a great potential for improving the mechanical properties ofcomposite cement. The results showed that the addition of TiO2 had a positive effect on compressive strength. Increasing TiO2 nanoparticles content of more than 3 wt% is caused to reduce the compressive strength according to past studies. But in this study is shown that by adding 3% nanocillis or 20% silicified to increased TiO2 nanoparticles content of more than 3% wt, the results ofcompressive strength are not reduced. The use of 3% combined nano-silica or 20% silicafium will cover this defect of increased TiO2 nanoparticles content ofmore than 3% wt.

The HA- Al2O3 nanocomposite was produced by the precipitation method. In thefirst study, the effect of MgCl2.6H2O and NaF additives on HA-Al2O3 nano-composite powderwere studied and the second, chitosan / HA- Al2O3 scaffold was prepared byfreeze casting method. The phase and microstructure and morphology analysisof nanocomposite and scaffold were performed by XRD, FT-IR, FESEM, and TEM.X-ray diffraction test results along with infrared spectroscopy indicated that, theHA- Al2O3 nanocomposite without impurities was produced. TEM results showedthat the produced nano composite particle sizes were reported between 30-50nm.Moreover, the porosity percentages of scaffold without additive was about56% and with NaF as an additive was about 63 %, however, the scaffold withMgCl2.6H2O additive with 70% porosity had the highest porosity percentage. Thecompressive strength of the SFA scaffold exhibited a two-fold strength comparedto the SMA scaffold, which indicated the improved mechanical compatibility ofthe SFA scaffold.

In this paper, nanoparticles of copper oxide (CuO) were synthesized using solid-statethermal decomposition of the new copper precursor at 600 ºC for 3 h. Thecopper precursor was prepared from the mixture of CuCl2.6H2O and benzoic acidin H2O in the presence of KOH. Nanoparticles of copper oxide were characterizedby Fourier transform infer-red (FT-IR), UV-Vis, and photoluminescence (PL)spectroscopy X-ray powder diffraction (XRD) and transmission electronmicroscopy (TEM). All results confirmed the preparation of the pure phase of CuOnanoparticles. In addition, the adsorption of methyl green in an aqueous solution ofcopper oxide nanoparticles as adsorbent was studied at various parameters suchas adsorbent dosage and agitation time. It was found that methyl green dyeremoval increased by adsorbent dosage (0-30 mg) and contact time (0-120 min).This research revealed that the copper oxide nanoparticles could be used as asuitable adsorbent for the removal of various organic dyes from aqueous solutions.

Palladium nanoparticles (Pd-NPs) have various applications in industries, such as:Biomedicine, Sewage treatment, Electronics, and Catalytic processes. Differentstudies on NP have shown that they have negative impacts on different cellcategories in vitro. Despite extensive considerations, the molecular mechanismof Pd-NPs toxicity has remained elusive thus far. Therefore, in this paper,we investigated the toxicity of Pd-NPs by evaluating their effects on a humanlymphocyte. Blood lymphocyte cells were initially isolated by ficoll solution andwere exposed to Pd-NPs and Pd (II) ions. Then, we examined oxidative stress, cellcycle, and apoptosis employing flow cytometry. We found the NPs administrationsuppressed cell growth, which in turn resulted in cell apoptosis. Also, the cell cyclestopped at the sub G1 phase, resulting in DNA damage as well as profound ROSincrease. Our results showed that Pd-NPs treatment for 24 hours led to apoptosis,oxidative stress, as well as cell cycle blockage. It is notable that Pd (II) ions inducedmore severe toxicity. Our findings provide valuable insights on Pd-NPs toxicity.

CuWO4 nano-powder was synthesized via a hydrothermal reaction using CuCl2.2H2Oand Na2WO4.2H2O in the stoichiometric 1:1 Cu:W molar ratio and sodiumcitrate as raw materials. In addition, Ag3PO4 was synthesized by a precipitationmethod using Na2HPO4 and AgNO3. Finally, CuWO4-Ag3PO4 nanocomposite wassynthesized in a precipitation route using the as-synthesized CuWO4 and Ag3PO4as raw materials. The synthesized materials were characterized by powder X-raydiffraction (PXRD) technique. To investigate the effect of concentration of the basicsolutions on the morphology of the obtained materials, the morphologies of thesynthesized materials were studied by field emission scanning electron microscopy(FESEM) technique. As shown by the FESEM images, the morphology of CuWO4the material was spherical particles. Besides, the photocatalytic performance of theas-synthesized nanocomposites was studied for the degradation of ReactiveBlue 19 (RB19) under directly visible light irradiation. For this purpose, severalreaction parameters affect the degradation yield, such as catalyst amount, pHvalue and absence/presence of light were investigated. The data showed thatthe photocatalytic yield at the presence of light irradiation was more when theThe pH value of the solution was in the acidic range, the weight percent of silverphosphate in the composite mixture was more, and the catalyst amount wasmore. The findings revealed that a 0.05 g nanocomposite containing 0.24 mmoleof Ag3PO4, with an initial pH of 3 and RB 19 volume and concentration of 100 mLand 30 mg/L, respectively, could achieve approximately complete removal after30 min under visible light illumination.