Nano Glass Research Articles

Effect of Bioactive Glass Nano Particulates and Nano Hydroxyapatite Coated by Chitosan on Odontogenic Differentiation and Proliferation of human Dental Pulp Stem Cells

Effect of Bioactive Glass Nano Particulates and Nano Hydroxyapatite Coated by Chitosan on Odontogenic Differentiation and Proliferation of human Dental Pulp Stem Cells

Strain rate sensitivity of a Cu60Zr40 metallic and nanoglass

The strain rate sensitivity, m, of a binary Cu60 Zr40 nanoglass (NG) and metallic glass (MG) are investigated using nanoindentation. Indentations were performed at different loading rates in the range of 0.26–8 mN/s, which gives equivalent indentation strain rates over three decades. The load vs. displacement curves of MG exhibited noticeable displacement bursts at low loading rates, which gradually decreased with increasing loading rate suggesting a transition from more to less severe heterogeneous plastic flow. While in the case of NG, no noticeable displacement bursts are present at any of the loading rates suggesting a near homogeneous plastic flow. In both NG and MG, the hardness decreases with increasing loading rate, resulting in negative strain rate sensitivity, m. The m for NG is higher than the MG, indicating a more homogeneous flow underneath the indentation. Interface indentation experiments and subsequent analysis of the deformation zone showed a larger number of fine secondary shear bands (SSBs) in NG as compared to the primary shear bands (PSBs), while the plastic flow in MG is accommodated mostly by the PSBs. The findings of the current study will help improve the understanding of the plastic deformation behavior of NGs and provide insights for designing the novel microstructural architecture of amorphous alloys with improved ductility.

Salinity adjustment to improve the efficiency of nano glass flakes (NGFs) in interfacial tension reduction

Nanoparticles (NPs) have been recognized as the agents that can improve the oil recovery given their positive impact on the surface wettability of rocks. However, their impacts on the interfacial tension (IFT) of the two-phase fluid in a reservoir have not been widely reported. Given the significant impact of IFT on the oil recovery, it is important to develop an NPs based approach that not only alter the surface wettability but also reduce the IFT. This may be accomplished by combining nanofluids with low salinity water (LSW). In the present study, LSW and NPs are combined to study their impacts on the IFT of a two-phase flow system with water and oil. IFTs of different solutions with nano glass flakes (NGFs) and nano silica (Ns) were measured in the presence of monovalent and divalent salt ions. The results obtained were analysed using two different models as a function of time. It was found that NGFs and Ns have similar efficiency in reducing the IFT and can reveal an optimum performance once their concentration reaches 24.8% in the solution. It was observed that, unlike Ns, IFT can be further reduced by LWS in the presence of NGFs. In fact, reduction of salinity up to 3500 ppm can decrease the IFT in the NGFs solution by the salting-in effect or migration of oil components. Changing the pH of the system can also reduce the IFT, but fluctuations was observed once pH goes beyond 9. It appeared that the tension in the interface between water and oil reduces over time and the effect of adsorption time is significantly higher on the solutions with nanoparticles. It was concluded that combining NGFs with LSW not only reduces the concentration of NPs needed and can make the project economically feasible, but also favourably change the IFT during the flooding process. The findings of this study may help to understand how LSW, and nanofluids can be employed together for a better oil recovery.

Investigations on fracture response of warm mix asphalt mixtures with Nano glass fibres and partially replaced RAP material

In the present research, an attempt was made to develop the mix design for a novel Warm Mix Asphalt (WMA) with Sasobit warm mix additive, Reclaimed Asphalt Pavement (RAP) based aggregates and Nano Glass Fibers (GF). Aggregate blends, as per Bailey’s gradation guidelines, were adopted to prepare asphalt mixtures with high RAP replacement of 70 % along with incremental proportions of GF, ranging from 0.2 % to 0.4 % with 0.1 % steps. Further, these specimens were tested and evaluated for their fracture properties. The mixtures with 70% RAP and 0.3% GF have exhibited 3.3 times the sustained peak load, 1.76 times the fracture energy and 1.8 times the critical strain energy release when compared with the reference asphalt concrete mixture, proving the efficacy of the modification being attempted during the present research. Further, this mixture was found to exhibit satisfactory performance with regard to the Tensile Strength Ratio (TSR), resilient modulus and the rut resistance. X Ray diffractograms (XRD) for the Sasobit blended binders have indicated a semi crystalline structure while the aging indices, derived from Fourier Transform Infrared Spectroscopy (FTIR), conducted on these binders, revealed improved aging resistance for the Sasobit blended binder.

Short to medium range order and atomic dynamic property within the surface of nanoscale metallic glasses revealed by molecular dynamics simulations

The surface microstructure and its atomic dynamic property of a metallic glass nano pillar were investigated by using molecular dynamics simulations. The short-range order motifs in the surface contain a large number of unstable bonded pairs and clusters, leading surface to approach the structural property of liquid phase. A proportion of <0, 0, 12, 0> clusters in the surface constitute chain-like super clusters, but its overall degree of medium-range order is lower than that in the core region. The atomic mobility in the surface at different scales are enhanced significantly. Generally, the lower the degree of order for the cluster, the stronger its migration ability. The surface region could be divided into three consecutive sublayers, which are solid-like layer, semi-solid layer and liquid-like layer. The content of liquid-like clusters increases sequentially in these three sublayers. A schematic illustration of the relationship between the hierarchical structure and the possible relaxation modes was proposed.

Excess free volume and structural properties of inert gas condensation synthesized nanoparticles based CuZr nanoglasses

Nanoglass (NG) as a new structure-tunable material has been investigated using both experiments and computational modeling. Experimentally, inert gas condensation (IGC) is commonly employed to prepare metallic glass (MG) nanoparticles that are consolidated using cold compression to generate an NG. In computational modeling, various methods have been used to generate NGs. However, due to the high computational cost involved, heretofore modeling investigations have not followed the experimental synthesis route. In this work, we use molecular dynamics simulations to generate an NG model by consolidating IGC-prepared Cu64Zr36 nanoparticles following a workflow similar to that of experiments. The resulting structure is compared with those of NGs produced following two alternative procedures previously used: direct generation employing Voronoi tessellation and consolidation of spherical nanoparticles carved from an MG sample. We focus on the characterization of the excess free volume and the Voronoi polyhedral statistics in order to identify and quantify contrasting features of the glass-glass interfaces in the three NG samples prepared using distinct methods. Results indicate that glass-glass interfaces in IGC-based NGs are thicker and display higher structural contrast with their parent MG structure. Nanoparticle-based methods display excess free volume exceeding 4%, in agreement with experiments. IGC-prepared nanoparticles, which display Cu segregation to their surfaces, generate the highest glass-glass interface excess free volume levels and the largest relative interface volume with excess free volume higher than 3%. Voronoi polyhedral analysis indicates a sharp drop in the full icosahedral motif fraction in the glass-glass interfaces in nanoparticle-based NG as compared to their parent MG.

Effect of the addition of nano glass powder on the compressive strength of high volume fly ash modified concrete

Using high-volume fly ash as a cement alternative has gained popularity among researchers since it reduces CO2 emissions by minimizing cement production. However, the low strength at early ages remains the main barrier to replace cement with significant amounts of fly ash. Due to their abundance and low cost, nanoparticles derived from waste glass bottles may represent a potential material to boost strength at early ages. It possesses sufficient pozzolanic properties to contribute by a pozzolanic reaction which helps to compensate for the early strength loss associated with high volume fly ash (HVFA) concrete. The purpose of this study is to develop HVFA concrete mixture containing glass powder as a nano additive. To accomplish this, two groups of samples were prepared with 50% fly ash as a cement substitute and 5% and 10% waste glass powder as nano additives. Based on the water content, two groups were prepared. Group 1 was prepared with a water/cement (w/c) ratio of 0.5, while group 2 with w/c of 0.45. The results indicated that the workability of concrete was decreased when glass nanoparticles were added for both groups. However, with regard to compressive strength, the study discovered a significant improvement, particularly when 5% glass nanoparticles were used, which demonstrated high performance comparable to that of control samples of normal concrete.

Producing Sustainable Concrete using Nano Recycled Glass

Background: Many tools and techniques have been recently adopted to develop construction materials that are less harmful and friendlier to the environment. New products can be achieved through the recycling of waste material. Thus, this study aims to use recycled glass bottles as sustainable materials. Objective: Our challenge is to use nano glass powder by the addition or replacement of the weight of the cement for producing concrete with enhanced strength. Methods: A nano recycled glass powder is prepared by crushing and storming a glass bottle to obtain a Blaine surface area of approximately 28 m2/g and conforming to the chemical requirements for natural pozzolana class N, according to ASTM C618. The outcome of using nano recycled glass for theaddition and replacement of ordinary Portland cement weight on the compressive and flexural strengths of concrete at 7, 28, and 90 days is investigated. Results: The concrete mixes with 2.5%, 5%, 7.5%, and 10% replacements of cement by nano recycled glass powder show improvements in compressive and flexural strengths of up to 12.77% and 7.66%, respectively, at 28 days. Meanwhile, mixes with the addition of 5% nano glass powder show best improvements in compressive and flexural strengths of up to 11.49% and 7.46%, respectively.

Experimental Study of Elevated Temperature Effects on Properties of Nano Clay and Glass Fiber Concrete

Concrete is mostly use construction material. Concrete is composite material composed of fine and coarse aggregate bonded together with a cement paste that cure over time. Generally concrete is strong in compression and weak in tension. Concrete is brittle material and will crack when we increasing tensile force. Nano clay are nano-size particles of layered mineral silicates. Adding a nano clay is a could fill the original hydration products pores and colloid capillaries increase the cement paste density of concrete. Alkali-resistant glass fiber has a high degree of corrosion resistance in the environment of cement and other alkaline medium. Glass fiber gives high tensile strength. Objective of research is increase mechanical strength of concrete with use of nano clay (NC) and glass fiber (GF). In present study, Concrete grade use is M30.In study 2% of NC is fix replacement of cement and variation of GF is use 0.5%,1%,1.5% as admixture. Temperature effect give 80℃,180℃,300℃for 3 hours. After adding NC and GF check the difference test result like a slump, Compressive, split tensile and flexural strength test. The specimens will be tested on 3,7, and 28 days.

Evaluation of the nano silica and nano waste materials on the corrosion protection of high strength steel embedded in ultra-high performance concrete

Corrosion resistance of high strength steel (HHS) embedded in ultra-high performance concrete (UHPC) immersed in 3.5% NaCl solution is evaluated in the absence and presence of nano silica (NS), nano glass waste (NGW), nano rice husk ash (NRHA) and nano metakaolin (NMK) using open circuit potential, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) under normal and accelerated conditions. Data showed that the corrosion rate in the accelerated conditions is higher compared by the normal conditions due to the increasing in the rate of both anodic and cathodic reactions in the presence of anodic current. On the other hand, the presence of the studied nano materials decreases both the anodic and cathodic overpotentials, and shifts both the open circuit potential (Eocp) and corrosion potential (Ecorr) of HSS to more noble values, as well as decreases the values of the corrosion current densities (Icorr) in both normal and accelerated conditions. Furthermore, EIS analysis illustrates that the presence of these materials enhances both the concrete bulk resistance and the charge transfer resistance at HSS/UHPC interface, which retards the flow of the electrons between the anodic and cathodic sites, thus impeding the propagation of the corrosion process. The inhibitory effect of the studied nano materials for the corrosion of HSS is interpreted on the basis of the change in the microstructure and the compressive strength of the UHPC.

Enhanced Physical and Mechanical Properties of Flake–Shape/Vinyl-ester Nanocomposites Through Surface Modification of Graphene and Glass Flake: A Comparison with Simulated Data

: The main goal of this work was to investigate the effects of silane-modified graphene nanosheets (MGNS) and modified nanoglass flakes (MNGF) on the physical and mechanical properties of vinyl-ester resin (VER) composites. The surface modification was evaluated about these composites' physical and mechanical behavior by techniques such as water absorption, tensile, three-point bending, and dynamic mechanical thermal analysis (DMTA). The analytical data revealed that the silane functionalized nanocomposites improved the interface between the nanosheets and vinyl-ester matrix. It was found that surface modification could significantly improve the dispersion and adhesion of GNS and nanoglass flakes (NGF) compared with those of neat vinyl-ester and unmodified composites. The presence functionalization of NGF and graphene nanosheets (GNS) in vinyl-ester formulation did affect the tensile and flexural strength and modulus, water absorption, and storage modulus. GNS/VER exhibited higher tensile and flexural strength and modulus than the original composite. DMTA results also showed incorporation of NGF and GNS decreased glass transition and increased storage modulus relative to neat composites. Nonetheless, the incorporation of functionalized graphene nanosheets and nano glass flakes represent higher Tg and storage modulus.

Tuning the mechanical properties of nanoglass-metallic glass composites with brick and mortar designs

We use molecular dynamics simulations to characterize the tensile deformation and failure of metallic glass (MG)-nanoglass (NG) composites designed with a brick and mortar architecture consisting of a 3 nm-grain-size NG matrix and a MG second phase. Results show that the overall strength of the matrix is significantly improved by the second phase without sacrificing the large NG matrix ductility. The mechanical synergy of the two phases is optimized by arranging the MG bricks in a staggered way, which effectively delocalizes the plastic deformation, hindering the buildup of local stress hot spots and the generation of critical shear bands.

Mechanical Properties of Glassy Nanopillars: A Comparative, Computational Study of Size Effects in Nanoglasses and Homogeneous Bulk Glasses

We study the mechanical properties of nanoglass (NG) nanopillars with diameters from \unit[4.5]{nm} to \unit[54]{nm} by means of molecular dynamics simulations and compare the results with those obtained for nanopillars prepared from homogenous bulk glasses. Nanoglass nanopillars of two different types of glasses, namely Cu$_{64}$Zr$_{36}$ and Pd$_{80}$Si$_{20}$, were cut from samples prepared by nanoparticle consolidation. The influence of nanopillar diameter on the deformation behavior and strain localization is investigated. Moreover, cyclic loading is used to explore the origin of stress overshoots in the stress-strain curves of NGs. Finally, from the calculated properties a deformation map for NG and HG nanopillars is derived.

Influence of composition on the mechanical properties of metallic nanoglasses: Insights from molecular dynamics simulation

The introduction of a glass–glass interface is an effective way to improve the plasticity of metallic glass. However, the strength–plasticity trade-off has not still been effectively overcome. Here, the effect of the composition on the mechanical properties and deformation behavior of the CuZr nanoglass (NG) is investigated under tensile loading by a molecular dynamics simulation. The results indicate that high-performance NGs can be obtained by adjusting the percentage of Cu atoms. There is a critical Cu content (i.e., 75%), which makes the NGs have both high strength and high plasticity. The results show that with the increase in the Cu content, the deformation mechanism of the NGs changes from necking to uniform plastic deformation and then to the nucleation and the growth of the main shear band. Our results underscore the importance of the composition in the design and preparation of high-performance metallic glass.

Nanomodification: An efficient method to improve cement integrity in CO2 storage sites

Carbon Capture and Sequestration (CCS) technology is an effective strategy to mitigate greenhouse gases released into the atmosphere. One of the challenges of the CCS sites, however, is the degradation of class G cement used to seal-off the injected intervals. It is known that in the presence of brine in depleted reservoirs or aquifers, cement may degrade due to the interaction of its alkaline component (Portlandite) with carbonic acid, causing seepage of CO2 and environmental contamination. Given the surface area, stability and inhibition characteristics of nanomaterials, they might be a good option to improve the performance of the cement in CO2 storage sites. In this study, attempts are made to show how two reliable nanomaterials (Nano Glass Flakes (NGFs) and Multiwall Carbon Nano Tube (MWCNTs)) can be used to improve the integrity of the cement in CO2 storage sites. A series of pre-carbonation and post-carbonation tests were conducted on the cement samples modified by NGFs and MWCNTs to compare their performances under a real storage site condition. It was found that the samples with 0.5 wt% NGFs and 0.05 wt% MWCNTs have the best performance against the attack of CO2. They could significantly resist against the carbonation and prevent the severe chemical reactions taking place in the presence of CO2. Given the fact that NGF is significantly cheaper than MWCNT, it could be a good choice to reinforce the cement used in the CCS storage site.

On the differences in shear band characteristics between a binary Pd-Si metallic and nanoglass

Shear band morphology of a binary Pd80Si20 nanoglass (NG) and metallic glass (MG) was investigated using bonded interface indentation technique. The results clearly indicate that the plastic strain in the subsurface deformation zone in NG is accommodated by very fine secondary shear bands in addition to a fewer primary shear bands while in MG it is mainly by primary shear bands. Furthermore, at any given indentation load, the size of the normalized subsurface deformation zone, χ, is found to be higher for NG compared to MG suggesting that the deformation of Pd80Si20 NG is more pressure sensitive and softer than MG. These differences in deformation characteristics between the NG and MG closely related to the intrinsic differences in the glass structure.

Sustainable pavement technologies - performance of high RAP in WMA surface mixture containing nano glass fibers

• WMA reduces viscosity thereby toxic emissions and energy utilization. • Bailey gradation deems packing characteristics and utilizes realistic site conditions. • Nano Glass Fibers enhances properties of higher RAP replaced pavements. Pavement engineer is facing challenging task for curtailing the energy consumption, natural resources, and emissions without a compromise in pavement performance characteristics. Warm Mix Asphalt (WMA) technology is one among the solution and has attained a great recognition in pavement construction. In this article base binder was modified with a wax compound (Sasobit) to reduce the overall energy consumption and toxic emissions during pavement construction. Bituminous Concrete mixture was prepared with varying packing characteristics, using Bailey’s method of gradation. It was observed that 3% sasobit dosage when blended to the base binder showed the better results in comparison to the other dosages. A comparative study on volumetric properties, mix stiffness, moisture susceptibility, and rutting characteristics were performed. Mix combinations were prepared with conventional and modified binders with different proportions of Reclaimed Asphalt Pavement (RAP) and containing Nano glass fibers. A Higher percentage of RAP up to 80% and with 5% rejuvenator as vegetable oil was used in the study. The results obtained showed that 70% RAP mix displayed a drastic increment in the performance properties by almost 25% when compared to the conventional mix. Additional reinforcement in the form of Nano Glass Fibers was utilized to enhance the properties of RAP mixes. The performance properties of the 70% RAP mixes was observed to have an additional increment by almost 15% with the addition of 0.3% Nano glass fibers thereby laying a path for sustainable pavement technologies in the pavement construction industry.

Performance of green RPC containing nanoparticles and reinforced with hybrid fibers used for repairing damaged concrete

Recently, there is an increased research awareness towards the use of high strength cementitious matrices like reactive powder concrete (RPC) for rehabilitation and repairing damaged structures in addition to their use in the maintenance of concrete structures. Therefore, this research has been conducted to present some RPC mixes prepared from various percentages of cement replacement, nanoparticles materials, and reinforced with three different types of fibers.The green RPC mixes were prepared with a total 30 % replacement of cement by silica fume, slag powder, and glass powder. Then, the addition of Nanoparticles combination as 2.5 % Nano glass powder (NG) plus 2.5 % Nano Iron slag powder (NS) was performed. Besides, the uses of mono micro steel fibers and hybridization of micro steel fibers (MSF), sisal fibers (SIF), and human hair fibers (HHF) were achieved. The combined systems of substrate concrete and such different green RPC mixes which were proposed here as repair materials besides epoxy were tested in bi-surface shear, oblique shear, flexural bond strength, splitting bond strength, and Pull-out.The results showed that the reinforcing of green RPC with hybrid nanoparticles (2.5 %NG + 2.5 %NS) and hybrid fibers (1.5 %MSF with 0.25 %SIF and 0.25 %HHF) boosted the best performances among green RPC mixes in bi-surface shear, oblique shear and Pull-out tests. Also, the said mix gives higher bond strengths between RPC with substrate concrete than that of epoxy by 2.273 %, 3.663 %, 6.168 % and 10 % through bi-surface shear, oblique shear, splitting strength and flexural strength, respectively.

Changes in the Surface Roughness of Glass Ionomer Cement and Zirconomer after Immersion in Carbonated Beverages

Nano glass ionomer cement (GIC) with nano zirconia as a raw material called zirconium is a newly developed type of restoration/tooth filling material that is used in dentistry. Objective: To examine the effect of carbonated beverages on the surface roughness of Zirconomer and GIC filling materials and determine if there was any difference between them. Methods: This is a true-experimental laboratory research study with a pre-posttest group design. The research samples consisted of 32 samples, 16 GIC samples and 16 Zirconomer samples, further divided into four time-sensitive groups: day 1, day 3, day 5, and day 7. The samples were immersed in artificial saliva and carbonated beverages for 24 hours. Surface roughness was measured using a surface roughness tester. Results: The average surface roughness from day 1 to day 7 of the GIC material immersed in carbonated beverages was 4.17 μm, which is higher than the average surface roughness of Zirconomer (3.091 μm), and the difference was significantly different (pConclusion: Zirconomer was found to be more resistant to carbonated beverages than GIC. There was a positive correlation between the length of immersion time in the carbonated beverages and the surface roughness of GIC and Zirconomer.

Nano Glass Ionomer Cement And Its Properties

Nano Glass Ionomer Cement And Its Properties