material science

Characteristics of Silver-Hydroxyapatite/PVP Nanocomposite

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Metal nanoparticles play an important role in many different areas such as catalysis, electronics, sensors, and cancer therapy. Silver, in its many oxidation states (Ag0, Ag+, Ag2+, and Ag3+), has long been recognized as having an inhibitory effect towards many bacterial strains and microorganisms commonly present in medical and industrial processes. Silver was introduced in various materials including hydroxyapatite due to its biocompatibility. The unique size-dependent properties of nanomaterials make them superior and indispensable.

nanobiomaterials pdfIn this work, nanohydroxyapatite/poly vinylpyrrolidone composite was doped with 2 different concentrations of silver nanoparticles prepared by reduction method. Several techniques like TEM, XRD, FT-IR, and SEM with EDS were used to characterize the prepared samples. The bioactivity test (soaking in SBF) at different short time intervals was characterized by using inductively coupled plasma-optical emission spectroscopy (ICP-OES) method. It is demonstrated that silver-doped nanohydroxyapatite obviously improves the bioactivity of the apatite at the early stages of immersion. The antibacterial inhibition over 3 types of bacteria (Staphylococcus aureus, Streptococcus mutans, and Pseudomonas) is under investigation.

Biological Behavior of MG63 Cells on the Hydroxyapatite Surface

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hydroxyapatite journal pdfThe response of human bone marrow cell to bone ash-derived hydroxyapatite (HA) and tuna bone derived HA powders was compared. HA ceramics were prepared from the commercial bone ash and waste of tuna bone. HA powders were prepared by soaking the bone ash and tuna bone in 0.1M of NaOH solution at 80 °C for 4 hours. Both powders were calcined at 800 °C for 1 hour to completely remove organic and were attritor-milled for 24 hours. The bone ash-derived HA (AHA) and tuna bone-derived HA (THA) ceramics were prepared by cold isostatically pressed and sintered 1200 °C with a dwell time of 1 hour. A human bone cell line MG-63 cells were used to test biocompatibility of AHA and THA ceramics. Cell suspensions in DMEM containing 10% FBS and 1% penicillin-streptomycin were seeded onto 24-well plate containing THA and AHA ceramics. Cell proliferation was evaluated by MTS assay, and cell morphology was observed by SEM.

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The Creation of the Russian Production of Metal Powders as a Basic Element Additive Technology

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Additive technology based on the principle of concept formation and summation of the positive merits of different technological solutions in the life cycle of the receipt of the product, are becoming more widespread in the twenty-first century. The methodology of this process is based on the use of digital technologies and on the basis of 3-D computer models of real parts.

powder metallurgy pdfThe loop starts from the idea of designing and manufacturing a prototype and then creates the production and its disposal after use. It can radically reduce the time and cost of producing complex functional parts and products with unique properties. Also provides reduced energy costs in the production of marketable products of a given quality and reduces greenhouse gas emissions, improves the environment for running industrial enterprises.

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Preparation and Optimization of Buccal Propranolol Hydrochloride Nano ethosomal Gel: A Novel Approach for Enhancement of Bioavailability

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metabolism journals impact factorPropranolol hydrochloride is widely used in the treatment of hypertension and other cardiac conditions. However, the drug is extensively metabolized in the liver. The purpose of this research was to formulate and optimize a nano ethosomal buccal gel of propranolol hydrochloride in an attempt to improve its bioavailability. The ethosomes were prepared using cold method whereas a 23 full-factorial design was employed to investigate the effect of phosphatidylcholine (PC), propylene glycol (PG), and ethanol concentration on entrapment efficiency, particle size and % of drug released. The adjusted and predicted coefficients of determination as well as the CV% were used to assess the fitness of the experimental model. The optimized formulation F5 containing (1% PC, 10% PG and 50% ethanol) was incorporated in 1% Carbopol 934 gel base.

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Assessing Biaxial Stress and Strain in 3C-SiC/Si (001) by Raman Scattering Spectroscopy

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Highly strained 3C-SiC/Si (001) epilayers of different thicknesses (0.1 μm-12.4 μm) prepared in a vertical reactor configuration by chemical vapor deposition (V-CVD) method were examined using Raman scattering spectroscopy (RSS). In the near backscattering geometry, our RSS results for “as-grown” epilayers revealed TO- and LO-phonon bands shifting towards lower frequencies by approximately ~2 cm-1 with respect to the “free-standing” films.

material sciences pdfRaman scattering data of optical phonons are carefully analyzed by using an elastic deformation theory with inputs of hydrostatic-stress coefficients from a realistic lattice dynamical approach that helped assess biaxial stress, in plane tensile- and normal compressive-strain, respectively. In each sample, the estimated value of strain is found at least two order of magnitude smaller than the one expected from lattice mismatch between the epilayer and substrate.

Production of α-TCP Ceramic Precision Spheres for Mosaic-Like Ceramics Fabrication Use

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Porous ceramic biomaterials, namely, “artificial bone” are achieving some mainstream acceptance in the field of regenerative medicine on hard tissues. Recently, the numbers of artificial bones and their manufacturing process are found on papers and webs, and the situation implies as if we affirmed acceptable artificial bones. However, there seem to exist unsolved issues in the situation of artificial bone-based therapy.


ceramics journal impact factorUnsolved issues are establishing custom-made method and assurance of high connectivity and geometrical features of pores in ceramic artificial bones. Because they are highly production-dependent matters, innovative production process that guarantees the issues is required. To address the innovation, we developed an original method for porous ceramics fabrication named “Mosaic-like ceramics fabrication (MLCF)” that fabricates porous ceramics in brick-like manner.

Investigation of Gum Arabic and Its Suitability as a Composite Binder for Core Production

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Gum Arabic, exudates of several species of acacia, is typical of gum that contains Arabin. Gum Arabic of finest quality is obtained from Acacia Senegal and A. Arabica found in western and northern Africa. The Gum forms a clear thick solution in water. In this work, the foundry properties of Gum Arabic were investigated to ascertain its suitability as a composite binder for core production.

mining open access journalsVarious percentages of Gum Arabic and some conventional foundry binders were prepared and their binding properties determined. Since the binder has low limit hydration, it does not require the use of much water during mixture preparation. For the purpose of this work, 4%-6% of the Gum Arabic was used with conventional binders like bentonite, water glass, industrial starch, linseed oil to prepare core mixtures. A higher percentage (13-15%) of Gum Arabic alone was also used. Foundry properties like permeability, scatter index; mould ability index, moisture content, compressive strength tests and refractoriness were examined. The results revealed that the binder has a low refractoriness of 1200°C. This has the advantage of enhanced and good collapsibility during knock out.