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The present investigation has been conducted in order to study the fatigue and corrosion fatigue behaviour of an aluminium alloy (99,5%Al) substrate coated with a 106 MXC deposited by thermal spraying in electric arc. It has been determined that the deposition of such a coating on the aluminum substrate gives rise to significant gains in fatigue life in comparison with the uncoated substrate, when testing is carried out both in air and in a 3,5 wt.% NaCl solution. It has been shown that during testing in air, the fatigue gain ranges between ~131 and 186%, depending on the maximum alternating stress applied to the material. Larger fatigue gains are associated with low alternating stresses. Also, when fatigue testing is conducted in the NaCl solution, the gain in fatigue resistance varies between ~124 and 159%. Fatigue cracks have been observed to initiate at the coating surface and then grow towards the substrate after propagating through the entire coating thickness. Although in the present work residual stresses were not measured, it is believed that the gain in fatigue life of the coating–substrate system is due to the presence of compressive residual stresses within the coating which hinder fatigue crack propagation. The deposition of the coating does not give rise to significant changes in the static mechanical properties and hardness of the aluminum alloy substrate.

In this paper it has been deposited films of titanium oxide (TiO2), on a support of glass, by a D.C. magnetron sputtering system, by varying the working pressure (p = 2∙10-3 - 6.5∙10-3mbar) of the substrate temperature on three levels. The obtained layers were investigated and characterized by optical microscopy, Scanning Electron Microscopy SEM, X-ray diffraction and Atomic Force Microscopy. It was observed that, by modifying technological parameters of the process (working pressure and substrate temperature) it is changing the initial orientation of the compounds ((100) turns into (101) or (002)). The AFM analysis has allowed the observation of the fact that the average roughness of deposited films, expressed as RMS, has increased over 98% at the increasing of sputtering pressure from 2 10-3mbar to 6.5 10-3mbar. SEM analysis showed that the density of the deposit increases with substrate temperature. The granulation of the films obtained, presents an increasing trend with the variation of process parameters.

The purpose of this study was to analyze the published cases regarding large ovarian masses in adolescents, in order to find useful clinical implications for the diagnosis and management of the condition. The methodology employed a systematic review of reported cases of large/giant ovarian tumor in adolescence. The main objective was to assess the imagery findings, histology of the tumor, and the type of surgery performed. Our study included 58 patients with the tumor diameters ranged between 11-42 cm, with a median value of 22.75 cm and a mean diameter of 24.66±8.50 cm. The lesions were benign in 47 cases (81%), borderline in 2 cases (3.4%), and malign in 9 cases (15.6%). We found no statistically significant difference (p>0.05) between the size of the tumors and the ovarian markers levels. At the same time, a statistically significant difference was identified (p=<0,001) between elevated levels of the serum markers and the malignant tumor type (OR=12.45; CI95= 2.55-94.77). The main types of surgery performed were cystectomy (35 cases), oophorectomy (4 cases), salpingo-oophorectomy (18 cases). Open laparotomy was performed in 46 cases on tumors with a median diameter of 25 +/-8.8 cm, while laparoscopy was done in 12 cases on tumors with a median diameter of 23.7+/-7.6 cm. For optimal surgical management, it is advisable to assess first the imagery findings and tumor markers. Then, the laparoscopic approach should be considered as a feasible option, especially in cases where there are no predictive factors for a malign disease.