REVIEWING AND EVALUATION OF NEW MATERIALS USED AS SUBSTRATES

1984 ◽  
pp. 467-474 ◽  
Author(s):  
O. Verdonck
Keyword(s):  
2017 ◽  
Vol 907 ◽  
pp. 104-118
Author(s):  
Maria Stoicănescu ◽  
Eliza Buzamet ◽  
Dragos Vladimir Budei ◽  
Valentin Craciun ◽  
Roxana Budei ◽  
...  

Dental implants are becoming increasingly used in current dental practice. This increased demand has motivated manufacturers to develop varieties of product through design, but also looking for new materials used to improve surface characteristics in order to obtain a better osseointegration. But the increase in the use of implants goes to a consequent increase in the number of failures. These failures are caused either by treatment complications (peri-implantitis), by fatigue breakage under mechanical over-stress, by defective raw material, or due to errors during the insertion procedures. Although they are rare, these complications are serious in dentistry. Before to market a dental implant to clinical practitioners, the product is validated among other determinations in number of biocompatibility research. Raw material issues, details about its structure and properties are less published by the scientific literature, but all this are subject of a carefully analysis of the producers. Breaking of dental implants during surgical procedures, during the prosthetic procedures or during use (chewing, bruxism, accidents, etc.), is the second most common cause of loss of an implant after consecutive peri-implantitis rejection. Although the frequency of this type of failure for a dental implant is much smaller than those caused by the peri-implantitis, a detailed study of broken implants can explain possible causes. The use of scanning electron microscopy (SEM) in the study of the cleave areas explain the production mechanism of cleavages, starting from micro-fissures in the alloy used for the production of dental implants. These micro-fissures in weak areas of the implant (anti-rotational corners of the polygons, etc.) could generate a serious risk of cleavage first time when a higher force is applied.


2002 ◽  
Vol 09 (05n06) ◽  
pp. 1675-1680 ◽  
Author(s):  
G. GORDILLO

The purpose of this work is to investigate new materials which present good properties to be used as optical window and buffer layer in thin film solar cells based on CdTe and CuInSe 2. As potential candidates for optical windows, two different bilayer systems were studied: ZnO/In x Se y and ZnO/ZnSe. They are planned to be used later in the fabrication of solar cells with structures CuInSe 2/ In x Se y/ ZnO and ZnO/ZnSe/CdTe. The methods used to prepare the different window materials, as well as the technological stages of the solar cell fabrication, will be described. Additionally, the optical and morphological properties of the window systems will be studied through transmittance and atomic force microscopy (AFM) measurements. Preliminary results obtained with Cu(In,Ga)Se 2 solar cells, fabricated using ZnO/In x Se y as optical window, will be reported. They will be compared with those obtained using ZnO/CdS as optical window, which is regularly used in this type of cells.


Author(s):  
Hamzeh Jamali

This article aims to demonstrate a solution in order for an optimization of PTSCs thermal efficiency. The solution focuses on the radiative heat transfers occurring within the absorber tube of a PTSC unit of a solar power plant situated in Shiraz, Iran as the paper case study. Since the existing heat transfers procedure all comes down to the optical properties of the materials used in the absorber tube of a PTSC unit, an ideal material selection can directly influence the heat transfers and consequently improve the thermal efficiency of a PTSC unit to a great extent. This paper comes up with new materials selection in which graphene nanostructure and BOROFLOAT 33 are respectively used as absorber tube coating and absorber tube glass cover for their exceptional optical and mechanical properties. Meanwhile, a numerical and analytical comparison is made between the thermal efficiencies of a PTSC unit in different states.


Author(s):  
Marufjon Mukhtorovich Mamajonov ◽  
Pavel Evgenievich Lushchik ◽  
Murodjon Turgunbaevich Botirov ◽  
Yuri Gennadievich Alekseev

A review of modern literature on the development of biocompatible implants based on modern technologies, including bioengineering and nanostructuring, is presented. The advantages and disadvantages of implants based on metals and alloy, ways of improving their biological and mechanical properties are shown. In connection with the rapid development of many branches of science and technology, as well as in medicine, the problem arose of obtaining new materials, in particular, alloys with valuable physicochemical properties, which are used for the implant of cardiology, traumatology, orthopedics and other industries. Study of biocompatibility of medical devices based on metals and alloys, search for ways to overcome the low engraftability of implanted structures.


10.6036/10297 ◽  
2021 ◽  
Vol DYNA-ACELERADO (0) ◽  
pp. [ 5 pp]-[ 5 pp]
Author(s):  
BEATRIZ IVORRA ZARAGOZA ◽  
SILVIA NUERE MENÉNDEZ-PIDAL ◽  
SARA GOMEZ MARTIN ◽  
JUAN DAVID CANO MORENO ◽  
MIGUEL BERZAL RUBIO

The vibrations generated by manual machines can cause occupational diseases with both vascular and osteoarticular affectations, also known as hand-arm vibration syndrome. The pneumatic rotary hammer is one of these machines, widely used in the construction sector. In the bibliography consulted, it is found that the transmission of vibrations from the handle to the hand-arm system depends on both the composition of the material and the design of the handle. Although there are already improvements in this damping of vibrations received through the handles, there is a great field for its optimization, redesign and the search for new materials not yet used in the handles of pneumatic hammers. This article presents a methodology for the study of new materials used in the grip, including the analysis of the design, real tests for the characterization of the materials and their simulation by finite elements. The results obtained show that the design is a decisive factor for both vibration damping and weight. The redesigned grip that generates more damping at 33 seconds with a weight of 0.51kg is the "R1" with a value of 0.6346% better than the original grip, "Segeda original", with a weight of 0.55kg and with a damping value of 0.605%. Keywords: industrial design, pneumatic hammer, handle, elastomers, vibrations


2016 ◽  
Vol 35 (8) ◽  
pp. 799-803
Author(s):  
Yuchun Li ◽  
Hongliang Zhang ◽  
Yuwu He

AbstractOne way of controlling alkali chloride-induced corrosion in biomass boilers is by designing new alloy materials used as superheater tubes. Four newly designed Cr–Ni alloy was designed and studied for applicability in biomass power plants. High-temperature oxidation experiments and high-temperature corrosion experiments were carried out for evaluation material characterization. Through analysis and discussion of the corrosion kinetics and oxidation kinetics, it can be concluded that materials with series number of “2xx” and “3xx” had better endurance ability in KCl environment under 650°C and 700°C than TP316 material. In the same conditions, 3xx material had better anticorrosion ability in 700°C with KCl environment.


Sign in / Sign up

Export Citation Format

Share Document