सामग्री विज्ञान और इंजीनियरिंग जर्नल

A simple review of research literature and Research and Development trends (R&D) in the field of dental implants shows an exponential increase in their quantity. The impressive growth in the contributions of nanoscience, in general and nanotechnology/nanomaterials applied to dental care, in particular, also shows the priorities investments and substantive effort of the global research community in this area. Nevertheless, there are still many research challenges and huge opportunities to optimize dental implants. The essential purpose of this study is to assess biomimetic modifications on a novel low elastic modulus TiHfNb Alloy Ni-free. For the mimic surface samples were initially bioactive with Oxygen Plasma (OP) or Piranha etching (Pi). Later three different silanes were used (CPTES, GPTES or APTES+CL) and finally RGD or mixtures 1:1 of RGD:FHRRIKA or RGD:PHSRN were immobilized on the surface. To evaluate the biomimetic modification, cells adhesion studies were performed. For the chemical characterization different techniques were used, including, inter alia: X-ray Photoelectron Spectroscopy (XPS), Zinc-substitution complex technique (ZC), and immunofluorescence. Experimental results showed that the best activation method was the OP, and the biomimetic, modification is a well-grounded research strategy to improve the cell adhesion.

Ferrite coating of acid treated iron particles with have been optimized using electroless process. The effect of the functionalization was monitored by XPS and SEM analysis whereas adhesion behavior of ferrite thin films was characterized using a non-conventional ultrasonic test. It is shown that acidic treatments increase the amount of hydroxyl groups on the surface of iron particles, allowing the creation of chemical bonds between the iron core and its ferrite shell. It leads to an increase of the adhesion between both materials. It is shown that the reactivity of iron particles improves the ferrite deposition process. A homogeneous adhesive ferrite coating of around 2 μm with a deposition process of 90 min has been obtained.

Electroplastic graphene has been recently attracting considerable interest due to its intrinsic electrical, mechanical and thermal properties. This review has been presented the recent progress in preparation, application and bibliometric data of graphene published over twenty-eight years from 1986 to 2014. Recent researches clearly confirmed that graphene is one of very useful promising materials with applications ranging from electronics to biomedical systems such as biosensors, electrodes, and electromagnetic interferences. In addition to graphene, this article has been also introduced the synergistic effects of hybrid graphene-polymers on the properties of its composites. The emerging analyses of graphenes and their nano-composites have been finally discussed and proposed for the advances of electronics and biomaterials science and technologies.

The co-grinding processes for ZnO/CaO/Al(OH)3 and Zn4CO3(OH)6/CaO/Al(OH)3 powder compositions in a vibratory mill with an impact-shear loading were studied. The solid phase was investigated by the methods of X-ray diffraction, IR spectroscopy, scanning electron microscopy, synchronous thermal analysis and other methods. It was found that the formation of new Ca(Zn2(OH)6) phase takes place only in the ZnO-containing mixtures. The detected calcium hexahydroxodizincate dehydrate crystals had a prismatic shape. The experimental data showed also that the co-activation process is accompanied by the hydration of the particle surface due to the alignment of the basic properties of the initial compositions. The amount of gibbsite in the composition influences the changes in a crystal structure. The co-grinding of both compositions allows one to obtain the pellets which keep the mechanical durability after the saturation with HCl vapors. It was shown that the compositions with the basic zinc carbonate are characterized by the higher absorption capacity for the HCl vapors.

Stainless steels (SS) were invented to overcome the problem of corrosion which is a major concern of food and many other industries. The alloy of steel containing iron-chromium-nickel is known as stainless steels. Stainless steels typically contain between 9 and 30 percent chromium and varying amounts of nickel, molybdenum, copper, sulfur, titanium, niobium, etc., may be added to obtain the desired mechanical properties and service life. Stainless steel is considered noble metal for use in dairy industry. Stainless steels are classified based on the chemical composition and it provides information to overcome many types of corrosion. Some of the limitations of SS employed in food and dairy industry are attack by lactic and malic acids at elevated temperature and poor thermal conductivity. However, these limitations may be overcome by carefully selection and fabrication, optimized operating condition, care and maintenance of the equipment. Stainless steels of various grades are widely used as engineering material for the fabrication of equipment. Stainless steels are corrosive resistant but under certain conditions the materials can stain and can corrode. Dairy and food industries are concerned with reliability of equipment and product purity. To achieve these, stainless steels are often the economical and practical materials of choice for process equipment. It is necessary to select most suitable grade of SS depending on the requirements for the specific application. The understanding of metallurgy and ways of fabrication are very essential to select right grade of SS. The food and dairy processing industries, corrosion becomes a critical factor directly influencing equipment and indirectly, overall equipment longevity. Key to minimizing corrosion impact needs better understanding of factors affecting corrosion as early as the equipment design phase and throughout subsequent processing operation.

This paper tries to obtain the same mechanical performance with boron steel parts obtained by stamping, conventional quenching and tempering, with a subcritical annealing and tempering aimed at obtaining a dual structural steel. Thus, energy is saved in the annealing treatment to reduce the product temperature, and residence time, and the tempering treatment is suppressed. This results in process economics leading to the final product costs and environmental impact. This process is designed to equal the boron steel used in high-performance screws in the automotive industry, compared to dual structural steels used with for high manganese content and low carbon content. This is boron steel used in these applications and subjected to quenching prior subcritical annealing, can achieve the same strength and toughness values than conventional treatments.

To study the effects of soil-bags on the prevention of frost heave in canals in cold regions, experiments were conducted on models of soil-bags -treated and conventional canals subjected to freeze-thaw cycles. The amounts of frost heave and thaw settlement, water content and changes in temperature over time in the soil-bags-treated canals and conventional canals were studied. The experimental results showed that a significant frost heave-preventing effect was found in the soil-bags-treated canals subjected to freeze-thaw cycles, and the mechanism of the soilbags prevention of frost heave in canals was revealed. The frost heave-preventing effect of soil-bags was achieved by inhibiting the rising of capillary water and film water, in addition to introducing a reinforcement effect. The study provides a theoretical basis for the prevention of frost heaving in canals in cold regions.

Nd: YAG laser has been a versatile tool for variety of material processing in the modern manufacturing industries. Apart from the easy manipulation and robustness of Nd: YAG laser beam, its wavelength absorbed by wide range of materials. Therefore, the possibility of controlling and précised values for prominent operating parameters such as average peak power, average peak power density (APPD), mean power, pulse duration, pulse energy, pulse repetition rate, interaction, pulse overlap theory and its mathematical relationships were discussed for pulsed and continuous wave. Hence, the selection of satisfactory combinations of associated parameters to produce efficient and effective material processing with reduced defects.

In this work, we present a Single electron random access memories based on perceptron designs used as the basic artificial bio-inspired neural processing element. The operation principles are described and illustrated for the first time by simulations results. Combining the Monte Carlo method with a direct solution of the stationary master equation, we use SIMON simulator and MATLAB for training process. The main goal of this work is to build a multilayer neural network used in recognition and classification using single electron devices. We further provide a write/Erase/ Read states chronogram to provide the key element of our work which is the charge stored in output neuron’s quantum dots.

World energy consumption refers to the total energy used by all of human civilization. Since the heating costs in winter, the cooling costs in summer are very high in Turkey, insulation is made to the buildings to reduce these costs. A great part of the raw materials of insulation materials have been imported. Rapid increase in the population, developments in the technology everyday bring rapid consumption of energy resources with them. Today, the energy consumption has reached serious proportions and precautions have already been started to be taken all over the world. Most of the energy in Turkey is spent in industry and in housings. Energy savings potential is available up to annual $ 7.5 billion by the dissemination of heat insulation applications in Turkey. Energy efficiency should be supported in buildings via heat insulation in order to prompt this potential. In the present study, animal and vegetable fibre doped insulation material has been produced at specified rates. Set out in the findings, research materials waste animal and vegitables fibers shows that it is possible to produce insulation materials enough to mix it with plaster. The thermal insulation coefficient of the obtained samples conforms to the TS EN standards

Aluminium Metal Matrix composites is a relatively attractive material for automobile, aerospace and other engineering application due to its mechanical and tribological properties. To improve wear resistance and mechanical properties has led to design and selection of newer variants of the composite. The present investigation deal with the study of wear behavior of Al-SiC-Cu MMCs for varying reinforcement content, applied load, sliding speed, and distance. Aluminium MMCs reinforced with three different percentage of reinforcement 3, 6, 9% wt. SiC and 0.5, 0.75, 1.00% wt. Cu prepared by stir casting method. Wear test was performed by using “pin on disk” apparatus. A plan of experiment based on L27 Taguchi orthogonal array is used to acquire the wear data. An analysis of variance is employed to investigate the influence of four controlling parameters, SiC content, Normal load, sliding speed and sliding distance on dry sliding wear of the composites. It is observed that SiC content, sliding speed and normal load significantly affect the dry sliding wear. The optimal combination of the four controlling parameters is also obtained for minimum wear. The microstructure study of worn surface indicates nature of wear to be mostly abrasive.