20 research outputs found
Microwave sintering of nano size powder β-TCP bioceramics
A nano sized beta tricalcium phosphate (β-TCP) powder was conventional
sintered (CS) and microwave sintered (MW), in order to obtain dense β-TCP
ceramics. In this work the effect of microwave sintering conditions on the
microstructure, phase composition and mechanical properties of materials
based on tricalcium phosphate (TCP) was investigated by SEM (scanning
electron microscopy)and XRD(X-ray diffraction) and then compared with
conventional sintered samples. Nano-size β-TCP powders with average grain
size of 80 nm were prepared by the wet chemical precipitation method with
calcium nitrate and diammonium hydrogen phosphate as calcium and phosphorus
precursors, respectively. The precipitation process employed was also found
to be suitable for the production of submicrometre β-TCP powder in situ. The
β-TCP samples microwave (MW) sintered for 15 min at 1100°C, with average
grain size of 3μm, showed better densification, higher density and certainly
higher hardness than samples conventionally sintered for 2 h at the same
temperature. By comparing sintered and MW sintered β-TCP samples, it was
concluded that MW sintered β-TCP samples have superior mechanical properties
Effect of garlic on cardiovascular disorders: a review
Garlic and its preparations have been widely recognized as agents for prevention and treatment of cardiovascular and other metabolic diseases, atherosclerosis, hyperlipidemia, thrombosis, hypertension and diabetes. Effectiveness of garlic in cardiovascular diseases was more encouraging in experimental studies, which prompted several clinical trials. Though many clinical trials showed a positive effect of garlic on almost all cardiovascular conditions mentioned above, however a number of negative studies have recently cast doubt on the efficary of garlic specially its cholesterol lowering effect of garlic. It is a great challenge for scientists all over the world to make a proper use of garlic and enjoy its maximum beneficial effect as it is the cheapest way to prevent cardiovascular disease. This review has attempted to make a bridge the gap between experimental and clinical study and to discuss the possible mechanisms of such therapeutic actions of garlic
Elaboration et caractérisation de céramiques composites Al2O3 - ZrO2 à partir d'alcoolates.
International audienc
The effect of clay on foaming and mechanical properties of glass foam insulating material
In the current study, the main composition was prepared using soda-lime glass with dolomite [CaMg(CO3)(2)] as a foaming agent. The clay powder was added to the main composition in different ratios, and then, the mixtures were shaped by one-axial pressing. Differential thermal analysis (DTA) was used for the determination of crystallization temperatures, and the samples were heated according to the DTA results. Furthermore, heating microscopy was employed for studying the high-temperature behaviours of the mixtures. The samples were characterized using scanning electron microscopy, X-ray diffraction analysis, and comprehensive strength testing. Porosity and bulk density were measured to assess the foaming capability of the mixtures. The results showed that clay addition has a positive role on the mechanical properties of glass foam