Tribological characterisation of magnetron sputtered Ti(C, O, N) thin films

Ti(C, O, N) thin films were prepared by magnetron sputtering and analysed in terms of their tribological properties. Surface and tribological parameters were analysed and discussed as a function of the films composition and structural features, as well as their thickness. The evolution of friction coefficient values was in concordance with the wear behaviour of the films. According to the atomic composition of the films, an increasing of the carbon percentage and a compound chemical formula closed to the stoichiometric TiC lead to a very good wear behaviour. This aspect is also directly correlated with the friction behaviour.Fundação para a Ciência e Tecnologia (FCT) SFRH/BPD/27114/2006 e PTDC/CTM/69362/200

Performant DLC Films with Enhanced Wear Resistance

Diamond-like Carbon (DLC) coatings represent an interesting research subject for various groups of researchers having interests in surfaces tribology and corrosion. This paper discusses issues relating to the friction and mechanical behaviour, for 4 types of DLC coating systems deposited on heat treatable steel hardened and high-tempered (a multilayer of WC/C (a-C:H:W); CrC+a-C:H, a single layer of a-C:H, plasma nitriding + Si doped DLC (PN+Si-a-C:H). These films were synthesized using a single or a combined process consisting in either r. f. reactive magnetron sputtering or/followed by Plasma Assisted Chemical Vapour Deposition (PACVD). The tribological properties (friction coefficient) were obtained and discussed in correlation with the mechanical properties (the adherence, the nanoindentation hardness) and thickness When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3491

A Note on Doubly Warped Product Contact CR-Submanifolds in trans-Sasakian Manifolds

Warped product CR-submanifolds in Kaehlerian manifolds were intensively studied only since 2001 after the impulse given by B.Y. Chen. Immediately after, another line of research, similar to that concerning Sasakian geometry as the odd dimensional version of Kaehlerian geometry, was developed, namely warped product contact CR-submanifolds in Sasakian manifolds. In this note we proved that there exists no proper doubly warped product contact CR-submanifolds in trans-Sasakian manifolds.Comment: 5 Latex page

Photoluminescence Detected Doublet Structure in the Integer and Fractional Quantum Hall Regime

We present here the results of polarized magneto-photoluminescence measurements on a high mobility single-heterojunction. The presence of a doublet structure over a large magnetic field range (2>nu>1/6) is interpreted as possible evidence for the existence of a magneto-roton minima of the charged density waves. This is understood as an indication of strong electronic correlation even in the case of the IQHE limit.Comment: submitted to Solid State Communication

Pelvic floor disorders in gynecological malignancies. An overlooked problem?

Cervical, endometrial, ovarian, vulvar, and vaginal cancers affect women of a broad age spectrum. Many of these women are still sexually active when their cancer is diagnosed. Treatment options for gynecological malignancies, such as gynecological surgery, radiation, and chemotherapy, are proven risk factors for pelvic floor dysfunction. The prevalence of urinary incontinence, fecal incontinence, and sexual dysfunction before cancer treatment is still unclear. Hypotheses have been raised in the literature that these manifestations could represent early symptoms of pelvic cancers, but most remain overlooked even in cancer surviving patients. The primary focus of therapy is always cancer eradication, but as oncological and surgical treatment options become more successful, the number of cancer survivors increases. The quality of life of patients with gynecological cancers often remains an underrated subject. Pelvic floor disorders are not consistently reported by patients and are frequently overlooked by many clinicians. In this brief review we discuss the importance of pelvic floor dysfunction in patients with gynecological malignant tumors

фольклорно-етнографічні матеріали на сторінках журналу «Основа»

In the article folk and ethnographical materials of the «Osnova» magazine are analyzed. The role of this edition in development of the ethnography is defined

ANALYSIS OF GRID-CONNECTED PHOTOVOLTAIC SYSTEM INTEGRATON ON LOW-VOLTAGE DISTRIBUTION NETWORK

The introduction of new local sources on the distribution network will impact the quality of power in different ways. The low-voltage customers are strongly affected by the level of power quality, especially by harmonic distortions. In present paper, the impact on the power quality of a low-voltage utility network with an integrated PV system has been assessed at the point of common coupling of the PV system. In this order, the most representative power quality indices concerning the harmonic distortion have been monitored and compared with the limits set by the corresponding standards

Ti–Si–C thin films produced by magnetron sputtering : correlation between physical properties, mechanical properties and tribological behavior

Ti–Si–C thin films were deposited onto silicon, stainless steel and high-speed steel substrates by magnetron sputtering, using different chamber configurations. The composition of the produced films was obtained by Electron Probe Micro-Analysis (EPMA) and the structure by X-ray diffraction (XRD). The hardness and residual stresses were obtained by depth-sensing indentation and substrate deflection measurements (using Stoney’s equation), respectively. The tribological behavior of the produced films was studied by pin-on-disc. The increase of the concentration of non-metallic elements (carbon and silicon) caused significant changes in their properties. Structural analysis revealed the possibility of the coexistence of different phases in the prepared films, namely Ti metallic phase ( alpha-Ti or beta-Ti) in the films with higher Ti content. The coatings with highest carbon contents, exhibited mainly a sub-stoichiometric fcc NaCl TiC-type structure. These structural changes were also confirmed by resistivity measurements, whose values ranged from 10E3 Ohm/sq for low non-metal concentration, up to 10E6 Ohm /sq for the highest metalloid concentration. Astrong increase of hardness and residual stresses was observed with the increase of the non-metal concentration in the films. The hardness (H) values ranged between 11 and 27 GPa, with a clear dependence on both crystalline structure and composition features. Following the mechanical behavior, the tribological results showed similar trends, with both friction coefficients and wear revealing also a straight correlation with the composition and crystalline structure of the coatings

Properties changes of Ti(C, O, N) films prepared by PVD : the effect of reactive gases partial pressure

Dark Ti-C-O-N thin films were deposited by dc reactive magnetron sputtering. A titanium target was sputtered while three different gas flows were injected into the deposition chamber: argon (working gas), acetylene and a mixture of oxygen and nitrogen (reactive gases). The films were produced with variation of the gases flow rates, maintaining the remaining parameters constant. Varying the ratio between the reactive gases flow (gas mixture/acetylene) allowed obtaining films with different characteristics. The colour of the films was characterized by spectral reflectance spectroscopy, and expressed in the CIE 1976 L*a*b* colour space. An accurate control of the deposition conditions allowed obtaining intrinsic and stable dark colours for decorative applications. Composition analysis by electron probe microanalysis was done to quantify the elemental concentrations in the films. X-ray diffraction experiments revealed the evolution of the film structure which showed to be essentially amorphous, but with evidences of fcc structure.Fundação para a Ciência e Tecnologia (FCT) - SFRH/BPD/27114/2006 and PTDC/CTM/69362/2006

Classic vs laparoscopic approach in colorectal cancer. Experience of a tertiary center, Surgery No 3 Clinic, Cluj-Napoca

Clinica Chirurgie 3, Cluj-Napoca, România, Al XIII-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” și al III-lea Congres al Societății de Endoscopie, Chirurgie miniminvazivă și Ultrasonografie ”V.M.Guțu” din Republica MoldovaIntroducere: Cancerul colorectal este unul dintre cele mai frecvente cancere și cu tendință în creștere la nivel global. Majoritatea studiilor recente au demonstrat non inferioritatea și chiar o ușoară superioritate în abordul laparoscopic prin prisma rezultatelor obținute și a supraviețuirii la distanță. Material și metode: Au fost selectate retrospectiv 2186 de cazuri din baza de date completată prospectiv a Clinicii Chirurgie 3 pentru perioada ian 2013-dec 2018 (6 ani). Din acestea s-au exclus 76 cazuri laparoscopie/laparotomie exploratorie, 154 cazuri colostomii, 51 derivații interne; în final au fost analizate 1905 cazuri de cancer colorectal. Rezultate: Din 1905 cazuri s-au efectuat rezecții laparoscopice la un număr de 310 (16.27%) și clasice la un număr de 1595 cazuri (83.73%). Au fost analizați între cele două loturi următorii parametri: pregătire preoperatorie, durata operației, pierderi sangvine, complicații postoperatorii (fistulă, abces, hemoragie, ocluzie, complicații generale), supurații de plagă, zile spitalizare, necesar antibiotic, mobilizare postoperatorie, mortalitate. Concuzii: Abordul laparoscopic prezintă avantaje privind recuperarea postoperatorie, pierderi sangvine, zile spitalizare, necesar antialgice/antibiotic, lipsa supurațiilor de plagă. Dezavantajele sunt curba de învățare, aparatura specifică și dificultatea păstrării principiilor oncologice.Introduction: Colorectal cancer remains one of the most frequently diagnosed malignant pathologies with a continuously increasing rate worldwide. Most of the recent studies have shown the non-inferiority and slight superiority in the laparoscopic approach through obtained results. Material and methods: 2186 cases were selected retrospectively from a prospectively completed database of the Surgical no 3 Clinic in Cluj-Napoca over the course of 6 years (ian 2013 – dec 2018). Out of these cases, 76 cases were excluded for exploratory laparoscopy/laparotomy, 154 which underwent only colostomy, and 51 which underwent internal derivation. At the end of the study, 1905 cases were eligible. Results: Out of 1905 cases, 310 underwent a laparoscopic approach (16.27%) and 1595 cases underwent a classic approach (83.73%). Between the two approaches, a series of parameters were analyzed: preoperative care, duration of the surgery, intraoperative blood loss, postoperative complications (fistula, abscess, hemorrhage, occlusion, general complications), antibiotic necessity, postoperative mobilization, mortality, prevalence of surgical site infection. Conclusions: The laparoscopic approach proves many advantages regarding postoperative care, blood loss, hospitalization care, necessity of antibiotics and painkillers, and surgical site infection, cosmetic advantages. Disadvantages are the learning curve, specific instruments requirements, difficulty of maintaining the oncology principles