Functional Magnetite Nanoparticle: A Review on the Particles Lysis and Nucleic Acid Separation

The functional magnetite nanoparticles are one of the most important functional materials for nucleic acid separation. Cell lysis and magnetic separation are two essential steps involve in optimizing nucleic acid extraction using the magnetic beads method. Many coating materials, coupling agents, chemical cell lysis, and several methods have been proposed to produce the specific desired properties for nucleic acid extraction. The important properties, such as biocompatibility, stability, linking ability, hydrophobicity, and biodegradable, were considered. The appropriate coating material of magnetite core and coupling agent are necessary to give biomolecules a possibility to link with each other through chemical conjugation. In this review, progress in functional magnetite nanoparticles to optimize the high binding performance in nucleic acid extraction is discussed.

The Self-Adhesive Carbon Powder Based on Coconut Coir Fiber as Supercapacitor Application

Activated carbon powder is a popular material used as an electrode material for large scale applications, especially supercapacitors because of its excellent physical and electrochemical properties. Self-adhesive carbon powder based on coconut coir was prepared via single-step pyrolysis and chemical activation with NaOH solution. A single-step pyrolysis was performed, including carbonization and physical activation in the N2/CO2 atmosphere. The physical temperature of 750 °C, 800 °C, 850 °C and 900 °C is the major focus to evaluate the behavior of self-adhesive activated carbon. The density and the microcrystalline characteristics of the electrodes are influenced by the physical activation temperature. The density feature was evaluated based on the approach of self-adhesive carbon reduction dimensions such as mass, diameter, and thickness. Microcrystalline behavior was performed by using X-ray diffraction method, and it has shown the good amorphous properties of the activated carbon. The self-adhesive activated carbon electrodes were characterized and evaluated in symmetrical supercapacitor cells. The electrochemical characterization of the carbon electrodes using cyclic voltammetry method found that the high specific capacitance of 96 F.g-1 in 1 M H2SO4 electrolyte at a low scan rate of 1 mV.s-1 with energy specific and power specific of 13.33 Wh.kg-1 and 48.03 W.kg-1, respectively.

Synthesis of Ni-B/Hydroxyapatite by Electrochemical Method and Its Application as Catalyst on NaBH4 Hydrolysis

The result of burning hydrogen which is environmentally friendly makes hydrogen as a very attractive fuel. Hydrogen storage is interesting research material. One alternative to hydrogen storage is a metal-hydride as NaBH4. In this paper, the catalyst for hydrogen production from storage, namely The result of burning hydrogen, which is environmentally friendly, makes hydrogen a desirable fuel. Hydrogen storage is exciting research material. One alternative to hydrogen storage is a metal-hydride as NaBH4. In this paper, the catalyst for hydrogen production from storage, namely NaBH4, was synthesized by electrochemical. Ni-B catalyst with hydroxyapatite as catalyst support was prepared by electrochemical. Ni-B/HA catalyst was synthesized at various current densities (namely 67, 133, and 200 mA/cm2) and various electrolysis times (namely 30, 60, and 90 minutes). The resulting catalysts were analyzed by XRD and used as the catalyst for hydrogen production from the hydrolysis reaction of NaBH4. The fastest hydrogen production was obtained using a catalyst generated at 133 mA/cm2 and an electrolysis time of 60 minutes. The reaction rate equation for the hydrolysis of NaBH4 has a first-order reaction to the concentration of NaBH4. The resulting reaction rate constant ranged from 233.33 mL/g/min to 861.11 mL/g/min. The relationship between reaction temperature and reaction rate constant can be expressed by the equation k = 2.2x106exp (5534/T).

Synthesis of Metallic Zinc Nanoparticles by Reduction of Zinc Ions in Protonic Solvent

Simple and low environmental impact methods for producing chemically-stable nanoparticles of metallic zinc (Zn) are asked to be developed, because metallic Zn nanoparticles are easily oxidized in air, and organic solvents, which can be used for the fabrication of metallic Zn particles, give a great environmental impact. The present work focuses on the chemical reaction in protonic solvents containing aqueous solvents, of which the use will give a smaller environmental load, and proposes a method for producing metallic Zn nanoparticles by reduction of Zn ions in the protonic solvent. Two kinds of hydrophilic solvents were examined: water and ethylene glycol (EG). The use of water and EG as the solvents produced Zn oxide. Though the addition of aluminum salt to EG also produced Zn oxide, the crystallinity of Zn oxide was lower than that for with no addition of aluminum salt. In the case of the aluminum salt addition, nanoparticles with a size of 27. 5±13.3 nm were fabricated, and not only bonds of Zn-O-Zn and Zn-OH but also a bond of Zn-Zn were confirmed to be formed, which indicated the production of low crystallinity metallic Zn nanoparticles.

Microstructure Evolution and Mossbauer Spectroscopy Research of Nanostructured Ni3 Fe Intermetallic

Nanocrystalline Ni75Fe25 (Ni3Fe) powders were prepared by mechanical alloying process using a vario-planetary high-energy ball mill. The intermetallic Ni3Fe formation and different physical properties were investigated, as a function of milling time, t, (in the range 6 to 96 h range), using X-Ray Diffraction (XRD) and Mössbauer Spectroscopy techniques. X-ray diffraction were performed on the samples to understand the structural characteristics and get information about elements and phases present in the powder after different time of milling. The refinement of XRD spectra revealed the complete formation of fcc Ni (Fe) disordered solid solution after 24 h of milling time, the Fe and Ni elemental distributions are closely correlated. With increasing the milling time, the lattice parameter increases and the grains size decreases. The Mössbauer experiments were performed on the powders in order to follow the formation of Ni3Fe compound as a function of milling time. From the adjustment of Mössbauer spectra, we extracted the hyperfine parameters. The evolution of hyperfine magnetic field shows that the magnetic disordered Ni3Fe phase starts to form from 6 h of milling time and grow in intensity with milling time. For the milling time more than 24 h, only the Ni3Fe disordered phase is present with a mean hyperfine magnetic field of about 29.5 T. The interpretation of the Mossbauer spectra confirmed the results obtained by XRD.

Microstructural Investigation of Fluoroapatite Hydrothermally Converted from Hydroxyapatite Synthesized from Crocodile Eggshell

Fluoro/hydroxyapatite (FHAp) were prepared by hydrothermal at 150 °C for 24 hours with different of starting materials. The conversion of hydroxyapatite (HAp) and tricalcium phosphate to FHAp showed the rod-like shape with 200 nm. While, the morphology of FHAp from crocodile eggshell as CaCO3 form with different in phosphorus and fluoride source showed the unique structure evolution from rod-like hexagonal crystals, dumbbell to ball shape. Two distinctive morphology, first when using NaF as fluoride source with (NH4)2HPO4 precursor show the large cubic structure in high magnification it is tufted hexagonal crystal and it bundle like structure. As the pH value decreases in NH4F, it increases crystal size. For H3PO4 as phosphate precursor found that unique structure evolution from rod-like hexagonal crystals to dumbbell structure and then form the sphere assembly with a size of several micrometers.

Photocatalytic Activities of Cobalt-Doped ZnO Nanoparticles by Hydrothermal Method

Photocatalytically active cobalt-doped ZnO (Co: ZnO) hexagonal nanoparticles have been prepared by hydrothermal process. X-ray diffraction, SEM, FTIR and UV–vis spectroscopy confirmed that the dopant ions substitute for some of the lattice zinc ions, and furthermore, that Co2+ ion exists. The as-prepared Co: ZnO samples have an extended light absorption range compared with pure ZnO and showed highly efficient photocatalytic activity, only requiring 120 min to decompose ~90% of MB dye under sun light irradiation. The results indicated that a strong electronic interaction between the Co and ZnO was present, and that the incorporation of Co promoted the charge separation and enhanced the charge transfer ability and, at the same time, effectively inhibited the recombination of photogenerated charge carriers in ZnO, resulting in high visible light photocatalytic activity.

Phase Separation Effect in Gelation of 3DOM Bioactive Glass

The quaternary phase bioactive glasses (SiO2-CaO-Na2O-P2O5) were synthesized by the sol-gel process. Pluronic P123, using surfactant as structure-directing agents as well as phase separation inducers. The obtained bioactive glasses were characterized regarding morphology by using the scanning electron microscopy (SEM). Polymer colloidal crystals (CCTs) as the template component yielded either three-dimensionally ordered macroporous (3DOM) structure or hollow spheres shaped bioactive glass. The other type of morphology generation is related to the polymerization-induced phase separation (PIPS) in the gelation process. The heterogeneous precursor i.e. silica-rich regions caused the microspheres and solvent-rich areas produced micrometer-scale void space in bicontinuos structure. While the lower pH of starting precursor in 45S4P showed stronger precursor-template interactions than the 53S4P by generating the completely hollow spheres structure.

Analysis of the Stress-Strained State of Billets Processed by Rotary Forging with Special Shape of the Tool

In this paper, we investigated the process of rotary forging of commercially pure copper grade M2 ​​using standard and special-shaped anvils and presented the results of studies obtained by the method of numerical and physical modeling. It is established that the use of anvils with special geometric shapes provides a higher level of accumulated strain and the formation of more dispersed structural states with the same elongation ratio under conditions of multi-cycle processing [1]. The formation of a finer structure in its turn increases the hardness and strength of the material. In addition, the special shape of the anvils provides a positive field of values ​​of the Lode-Nadai coefficient in the cross section of the samples, predominantly in a range of 0.3-0.7 and, correspondingly, a more "comfortable" stress state close to non-uniform all-round compression, which contributes to increasing technological plasticity.

Effect of Zr on Structure and Resistance to Intergranular Corrosion of Severely Deformed 2024 Aluminum Alloy

Effects of severe plastic deformation by isothermal сryorolling with a strain of e~2 and subsequent natural and artificial aging on the structure and resistance to intergranular corrosion (IGC) of the preliminary quenched 2024 aluminum alloy of standard and Zr modified compositions were investigated. Increasing the temperature of aging leads to decreasing the alloy IGC resistance due to precipitation of more stable strengthening S-phase (Al2CuMg), rising difference of electrochemical potentials at grain and subgrain boundaries. Zr additions, оn the opposite, significantly increased the alloy IGC resistance in both naturally and artificially aged conditions, reducing its depth and intensity. The main structural factor, influencing the alloy corrosion behavior, is excess phases: their composition, volume fraction and distribution.