Nastase-Dan Ciobota, Gheorghe Ion Gheorghe and Veronica Despa
Additive Manufacturing (AM) concerns all classes of materials – polymers, metals, ceramics and glasses as well. For this reason, AM is in the focus of material scientists from all branches. Leaders of the industry realize that the possibilities of 3D printing are endless, and that these possibilities need ways and means to be taken full advantage of. Today, aerospace engineers are using the fused deposition modeling (FDM) method for rapid prototyping, part manufacturing, and tooling. They are followed by leaders and engineers from industry (industrial machines, motor vehicles, consumer products, medical/dental) but also from academic institutions and government/military.
Mihǎiţǎ Nicolae Ardeleanu, Simona Mihai, Ruxandra Vidu, Emil Mihai Diaconu and Ileana Nicoleta Popescu
A microfluidic device designated for measurement of fluidic flows with different viscosity, necessary within trapping/realising of cells/particles system has been developed. We use a new concept as Microfluidic Pulse Width Modulation (MPWM) for controlling transport of a single cell/particle. The image processing helped the nano-hydraulic volumes/flow rates measurement, through tracking inovative methods with the purpose to build a flow sensor. The device open an unique opportunitie for single cell study with applications in biomedical devices, tools for biochemistry or analytical systems.
There is a direct analogy between the mechanical and electrical phenomena related to vibrations and electromagnetic oscillations in the RLC series AC circuits and an inverse analogy to the electromagnetic oscillations in the RLC parallel alternative current (AC) circuits. Direct analogy RLC series AC circuit refers to the connection between complex velocity and complex electrical intensity, mechanical impedance and electrical impedance, etc. Reverse analogy RLC parallel AC circuits refers to the connection between complex velocity and complex electrical voltage, mechanical impedance and electrical admission, etc.
The paper presents a numerical method of kinematical analysis of the articulated quadrilateral mechanism, using the principle of virtual mechanical work for establishing the relations of connection between the kinematical parameters describing the movement of its elements.
The word-wide demand for energy is constantly increasing, and therefore ideas around future energy-generation are also on the increase with the aim of meeting this demand. This includes designs for the next generation of nuclear power reactors, such as gas-cooled, liquid-metal-cooled and water-cooled reactors; the goal being to create smarter ways to produce more economical, environmentally-friendly energy. The conditions such reactors would need to meet, present significant design challenges for scientist and engineers, not least around the structural materials and components to use. Depending on the operational conditions, use of elevated- temperature ferritic/martensitic materials such as P91 and P92 steel are favoured by several of the designs for use with out-of-core and in-core applications. The main goal behind this review article is to explain mechanical properties of P91 and P92 steel; these are two types of ferritic/martensitic steels. This reviewer, highlight and discuss the development of ferritic/martenisitc steels for nuclear programmes and to explain the effect of irradiation on mechanical properties of P91 and P92.
When the dynamic study of a solid rigid body subjected to links is wanted to be performed, the main difficulty is that the differential equations of motion contain in their structure the constraint forces which are unknown. Therefore it is necessary to remove them from the differential equations that describe the motion of the rigid body. The case of a wheel climbing on an inclined plane has been presented in this paper. It is considered that the wheel is rolling without sliding on an inclined plane.
Nicolae Angelescu, Dan Nicolae Ungureanu and Florin Toma
The paper is an attempt to present and evaluate of the some monolithic refractory materials, originating from our research activity, with potential to be used as the thermoprotective linings for the nonferrous metals and ferrous alloys manufacturing installations in foundries and steelworks.
Nicolae Angelescu, Dan Nicolae Ungureanu, Vasile Bratu and Florin Toma
This work is an attempt viewing to emphasize the possibility of using waste - as aggregate - from the demolition of silicoaluminuous refractory linings for manufacturing concrete with aluminuous cement. The article shows further on the possibilities of reducing the cement dosage and of using cheap admixtures.
Florina Violeta Anghelina, Veronica Despa, Carmen Popa and Constantin C. Anghelina
It is obvious that all the elements in a metallic prosthesis implanted in the human body may have beneficial or detrimental effects on the tissue-prosthesis interference. For this reason, the precise knowledge of the chemical composition and structure of an implantable metallic material becomes a major requirement for estimating the medical prosthesis behavior and minimizing the risk of rejection of the implant by the human body. This paper presents an elemental and structural analysis of some potentially biocompatible materials, such as AISI 316 and Co-Cr-Mo alloys.
Carmen Popa, Violeta Anghelina and Octavian Munteanu
The descriptive geometry constitues the foundation of the engineering sciences, so necessary to the specialists of this field. The aim of this paper is to establish the intersection curve between two cylinders and their unfoldings, by using the programmes:AutoCAD and Mathematica. We used the classical method and we first establish the intersection curve and then the cylinders unfoldings. To do this, we used the AutoCAD program. The same unfoldings can be obtained by introducing directly the curve equations (which are inferred) in Mathematica program.