Advanced Materials Research Vol. 1088

Abstract: This study was aimed at investigating the effect of the bone compositions on the fracture toughness of bovine cortical bone. A series of the SENB bovine cortical bone specimens were tested to assess the fracture toughness. Dual energy X-ray absorptiometry (DEXA) was applied to determine the mineral content of each bovine cortical specimen and hence the porosity and bone mineral fraction were measured. Current results indicate that the mean value fracture toughness is 9.37 MNm^3/2. Moreover, the fracture toughness was found to be significantly correlated with the apparent wet bone density and porosity of bone structure. No apparent correlations are found among clinical BMD and mechanical properties, implying that the BMD is an invalid indicator of the bone properties. Additionally, the tested data were fitted to the relationship, based on power law model, that the fracture toughness increase as a power (1.526) of increasing volume fraction and as a power of increasing bone mineral fraction (0.8195). These data indicate that small changes in the amount or density of compact bone tissue exert a more pronounced influence on fracture property.

Abstract: Heat-cured denture base resin is an important component in removable partial dentures and complete dentures, and has been widely used in the clinic. However, during long-term use, its appearance may be affected by varying degrees of color change, affecting the appearance and longevity of the dentures. In this study we examined the color changes and water absorption and solubility of dental base resins to investigate the color stability of four types of resin materials: New Century, Heraeus, Nissin and BASIS-HI. They were soaked in artificial saliva (as control), red wine, cola, coffee and tea separately at 37°C for 1, 4 or 12 weeks. Results are presented on which the color changes of dental base resin materials were associated with different denture base resins, soak solutions and storage times. We found that most of the dental resins became darker at prolonged immersion time. Heraeus resins showed more significant changes after soaking in red wine for 12 weeks, and its water absorption and solubility values were also greater than those of the other three types of resins. The color changes of New Century, Nissin and BASIS-HI soaked in the four solutions were relatively stable. The information obtained here will help optimize maintenance of dentures and also inform choice of denture materials.

Abstract: Objective: To investigate the formulation and technology for taste-masking granules. Methods: Clarithromycin was used as a model active pharmaceutical ingredient with bitter taste. Four preparation processes were compared, which were gelatin mono-condensation microcapsule method, calcium alginate microcapsule method, gelatin microsphere method and resin matrix granulation method. With taste masking effect and dissolution rate as evaluation indexes, the optimal preparation technology was studied. The orthogonal experiment was used to investigate the optimal formulation. Results: Clarithromycin granules prepared by the resin matrix granulation method had good taste masking effects and suitable dissolution rate. The optimal formulation was following: polyacrylic acid resin IV 0.85 g, PEG4000 0.30 g, sodium bicarbonate 0.10 g. The prepared clarithromycin granules have good taste masking effect and its dissolution in 45 min can reach 80.5%. Conclusion: The optimal formulation and technology can satisfy the request for taste masking and dissolution rate of clarithromycin granules.

Abstract: This study investigates the potential use of activated carbon prepared from Phragmites Australis for the removal of 2,4-dichlorophenol (DCP) and Rhodamine-B (RB) from aqueous solutions. P. Australis activated carbon (PAAC), a new adsorbent, was prepared from P. Australis by H₃PO₄ activation. Batch adsorption studies were conducted to evaluate the effect of various parameters such as pH, adsorbent dose, contact time and initial 2,4-DCP and RB concentration. Accordingly, the activated carbon developed in this study is effective and practical for utilization in wastewater treatment for 2,4-DCP and RB removal.

Abstract: Wastewater containing dyes and microbial bodies has attracted global attention because of the harmful effects on aquatic environment and human health. A considerable amount of dyes are present in the industrial effluents due to the loss during the processing of industrial products. The purpose of this study was to syntheses the composite particle for the effective removal of dyes and microbial bodies from aqueous solution. For this purpose, RGO supported nanocomposite was prepared using hydrothermal treatment of aqueous solution containing graphene oxide (GO), aqueous solution of silver nitrate and ferrous chloride tetrahydrate, and ethanol as precursor. Transmission electron microscopy, Raman spectroscopy, and X-ray diffraction indicated the formation of RGO supported silver doped iron oxide nanocomposite. As synthesized nanocomposite was highly effective for the adsorption of methylene blue and reduction of p-nitrophenol in aqueous solution, and also had high antibacterial capacity. The composite synthesis protocol is a simple and efficient to produce a unique composite for environmental remediation.

Abstract: Water-irruption is the second to gas explosion of major security problems in coal mine. The grouting material is composed of fly ash and montmorillonite separately according to a certain proportion with pure cement material. On the site grouting test and compare the compressive strength of the stones of the body and the size of the diffusion radius, and compare the grouting materials with pure cement materials. Through the comparative and analysis, the reasonable grouting materials are choosen.

Abstract: One of the energy alternatives that provide utility, flexibility, cleanliness and economy is biomass, such as forest waste (wood) and agricultural (sugarcane bagasse, rice husks, coffee pods, etc.). However, with its increasing supply and use grows also the concern of industries to invest in monitoring and control of emissions into the atmosphere, because during biomass burning are emitted as exhaust gases, fine particles known as particulates, which greatly contribute to the triggering of serious health problems to humans, in addition to the environmental damage. With that, this work aimed to conduct a monitoring of particulate and gaseous pollutants emissions to the atmosphere from the burning of various types of biomass used by industries. The equipment used for sampling were the optical monitor DataRAM 4 and the Unigas3000 + gas sampler. The results showed that biomass coffee pods presented the greatest concentration of particulates (485119 μg m^-3) with particle diameters between 0.0602 μm and 0.3502 μm, i.e. the most ultrafine particles, harmful to human health and the environment. The largest emissions of CO and NO_x were observed, respectively, for the coffee pods (3500 ppm) and for the rice husk (48 ppm). As for the superior calorific value (PCS), the best of fuel, with higher PCS, was the Eucalyptus grandis.

Abstract: Capacitive deionization (CDI) technology is a challenge on an economical and effective electrosorption desalination method. The paper analyses the CDI current status and progress of carbon electrode materials, and describes the types of CDI and its performances of testing materials. The electrosorption capacities are summarized on the carbon electrode materials and the current hurdles. The reported numbers from the literature vary in a wide range between 0.25 and 26.42 mg/g of both electrodes CDI cell, we suggest that the CDI electrodes should have an adsorption of at least 9.0 mg/g NaCl when the applyed voltage is 2.0 V. The potential capacitive deionization technologies are proposed here.

Abstract: The concentration of benzo [a] pyrene (BaP) was monitored at 40 selected sites of the Moravian-Silesian Region (Czech Republic) during winter and summer seasons. The concentrations of BaP were higher at all locations during winter than in the summer with a difference in values in the range of 0.66 to 47.08. The average concentration of BaP in the winter season was 14.67 ng/m³, whereas during the summer season this value reached 0.55 ng/m³. The highest average concentrations of BaP during winter and summer seasons in the values of 21.88 ng/m³ and 1.12 ng/m³, respectively were observed in the areas with predominant industrial activity. Conversely, the lowest concentration for both monitored periods were measured at the mountain and background sites and their values were 4.43 ng/m³ in winter and 0.07 ng/m³ in the summer. The value of the geochemical background was fixed at 1.79 ± 0.54 ng/m³. Finally, the value of diagnostic ratio of BaP and benzo [e] pyrene (BaP/BeP) greater than 1 indicated that the sources of BaP in the summer season were the local sources.

Abstract: Cu/Na-Sep samples were prepared by the incipient wetness impregnation method. These catalysts were characterized by means of XRF, XRD, and XPS techniques, and their catalytic activities were performed by the SCR of NO with propylene. The results show that the Cu/Na-Sep catalyst exhibited the high performance in the C₃H₆-SCR of NO. After investigation by XRD and XPS, the result showed that there are Cu²⁺/Cu⁺ redox species as a reaction activity center over Cu/Na-Sep.