Uticaj otapajućeg žarenja na svojstva čelika Nitronic 60a

Nitronic 60 (UNS S21800) is a highly alloyed austenitic stainless steel. This steel provides exceptional wear and galling resistance as well as a high temperature corrosion resistance. Increasing strength of Nitronic 60 is obtained by cold deformation. A solution annealing is necessary to achieve a complete austenitic microstructure without the presence of precipitates in the matrix. This paper describes determination of the appropriate heat treatment to obtain austenitic microstructure with a minimum consumption of time and energy.Nitronic 60 (UNS S21800) je visoko legirani austenitni nehrđajući čelik. Izraženo svojstvo ovog materijala je otpornost na habanje i trganje površine kao i otpornost prema visokotemperaturnoj koroziji. Najčešći postupak očvršćavanja čelika je deformacijsko, postupkom hladne deformacije. Da bi se postigla potpuna austenitna mikrostruktura bez prisustva precipitata u matriksu potrebno je izvršiti tzv. otapajuće žarenje. U ovom radu je opisan postupak određivanja odgovarajućeg toplinskog tretmana da bi se dobila odgovarajuća mikrostruktura uz minimalan utrošak vremena i energije

Analiza i ispitivanje nemetalnih uključaka za čelik 100Cr6

Steel 100Cr6 belongs to a group of hardened steels, which are applicable for production of rolling element parts. Because of specific working conditions, a proper chemical composition is required with a minimum content of nonmetallic inclusion. In this paper, the research results of presence the nonmetallic inclusions and their chemical composition are presented for the steel produced in vacuum and open induction electric furnace and their influence on the prescribed properties for this steel. The optical and scanning electronic microscope are used to identify presence and the chemical compositions of nonmetallic inclusions.Čelik 100Cr6 pripada grupi prokaljivih čelika koji su prvenstveno našli primjenu u proizvodnji dijelova kotrljajućih ležajeva. Glede posebnih uvjeta rada za ovu vrstu čelika se zahtijeva propisani kemijski sastav sa minimalnim prisustvom nemetalnih uključaka. U ovom radu su predstavljeni rezultati ispitivanja prisustva nemetalnih uključaka i njihov kemijski sastav za čelik 100Cr6 proizveden u vakuumskoj i otvorenoj indukcionoj elektro peći te njihov uticaj na svojstva propisane normom za ovu vrstu čelika. Ispitivanje prisustva nemetalnih uključaka kao i analiza kemijskog sastava urađena je primjenom optičkog i skening elektronskog mikroskopa

PHIL photoinjector test line

LAL is now equiped with its own platform for photoinjectors tests and Research and Developement, named PHIL (PHotoInjectors at LAL). This facility has two main purposes: push the limits of the photoinjectors performances working on both the design and the associated technology and provide a low energy (MeV) short pulses (ps) electron beam for the interested users. Another very important goal of this machine will be to provide an opportunity to form accelerator physics students, working in a high technology environment. To achieve this goal a test line was realised equipped with an RF source, magnets and beam diagnostics. In this article we will desrcibe the PHIL beamline and its characteristics together with the description of the first two photoinjector realised in LAL and tested: the ALPHAX and the PHIN RF Guns

Lepton pairs from a forbidden M0 transition:Signaling an elusive light neutral boson?

Electron-positron pairs have been observed in the 10.95 MeV 0(-) -> 0(+) decay in O-16. This magnetic monopole (M0) transition cannot proceed by gamma-ray decay and is, to first order, forbidden for internal pair creation. However, the transition may also proceed by the emission of a light neutral 0(-) or 1(+) boson, which might play a role in the current quest for light dark matter in the Universe

Anomalous internal pair creation in Be-8 as a signature of the decay of a new particle

In a measurement of the angular correlation of e(+)e(-) pairs in the isovector M1 decay from 1(+) level at 17.64 MeV in Be-8, a large deviation was found from quantum electrodynamics(QED)-prediction for internal pair conversion (IPC). By postulating the emission of a neutral particle with a mass of 12 (2.5) MeV/c(2) the structure of the angular correlation can be described

Epidemiology and cost analysis for patients with oral cancer in a university hospital in China

<p>Abstract</p> <p>Background</p> <p>Although several studies have reported the direct cost of oral cancer (OC), little research has invested the factors that could influence the costs of OC patient. This study analyzes the epidemiological characteristics and the direct cost of OC. More specifically, the study examines the relationship between patients' medical costs and influencing factors of epidemiology.</p> <p>Methods</p> <p>All patients encountered from January 2007 to December 2007 at the School of Stomatology of the Fourth Military Medical University (FMMU) in China with diagnosis of oral cancer have been selected. Medical hospitalization days (MHD) and cost per patient (CPP) of the samples have been calculated for different patient groups, and the results have been compared using statistical methods.</p> <p>Results</p> <p>A total of 456 oral cancer patients have been selected in this study. The epidemical characteristics are as follows: female/male 176/280; squamous cell carcinoma (SCC)/adenocarcinoma/sarcoma/lymphoma/other types 246/127/40/27/16; stage I/II/III/IV 90/148/103/115; smoker/non-smoker 136/320; rural/urban patients 82/374. Of all the patients, 82.24% were over 40 years of age. Rural patients were significantly younger than urban patients. SCC was the majority histology in older patients, while sarcoma was more common in younger patients. 372 of the patients received treatment and 84 gave up any treatment after diagnosis. Treatment cost accounted for majority of the payment. The CPP and MHD of patients in late clinical stage were higher than that of patient in early stage.</p> <p>Conclusion</p> <p>Gender, smoking habit and age older than 40 years are the epidemiological risk factors for oral cancer. Lack of medicare, smoking habit, late clinical stage and SCC are the high economic factors for patient medical cost.</p