Microhardness changes gradient of the duplex stainless steel (DSS) surface layer after dry turning

The article presents the gradient of microhardness changes as a function of the distance from the material surface after turning with a wedge provided with a coating with a ceramic intermediate layer. The investigation comprised the influence of cutting speed on surface integrity microhardness in dry machining. The tested material was duplex stainless steel (DSS) with two-phase, ferritic-austenitic structure. The tests have been performed under production conditions during machining of parts for electric motors and deep-well pumps

Investigation of the physical parameters of duplex stainless steel (DSS) surface integrity after turning

The article presents the influence of machining parameters on the microhardness of surface integrity (SI) after turning by means of a coated sintered carbide wedge with a coating with ceramic intermediate layer. The investigation comprised the influence of cutting speed on the SI microhardness in dry machining. The material under investigation was duplex stainless steel with two-phase ferritic-austenitic structure. The results obtained allow for conclusions concerning the exploitation features of processed machine parts

Investigation of selected surface integrity features of duplex stainless steel (DSS) after turning

The article presents surface roughness profiles and Abbott - Firestone curves with vertical and amplitude parameters of surface roughness after turning by means of a coated sintered carbide wedge with a coating with ceramic intermediate layer. The investigation comprised the influence of cutting speed on the selected features of surface integrity in dry machining. The material under investigation was duplex stainless steel with two-phase ferritic-austenitic structure. The tests have been performed under production conditions during machining of parts for electric motors and deep-well pumps. The obtained results allow to draw conclusions about the characteristics of surface properties of the machined parts

A novel fluorescent probe for NAD-consuming enzymes

A novel, fluorescent NAD derivative is processed as substrate by three different NAD-consuming enzymes. The new probe has been used to monitor enzymatic activity in a continuous format by changes in fluorescence and, in one case, to directly visualize alternative reaction pathways

Influence of argon pollution on the weld surface morphology

In this paper the surfaces of butt welded joints in steel tubes were analyzed using an optical 3D measurement system to determine the morphology and topographic parameters. It was established that pollution of the argon shield gas with oxygen did not influence the width of the heat-affected zone. However, the composition of the shield gas significantly influenced the surface asymmetry, Ssk, and its inclination Sku. The measurement of these parameters enabled the selection of a higher quality surface, which was visually proven by the reduction in discoloration of the surface of the weld joint. High quality surfaces eliminate a potential habitat for bacteria and a future source of corrosion as well as providing less resistance to fluid flow

Current status of drug-eluting stents and drug-eluting balloons in patients with stable coronary artery disease : an expert consensus document of the Association for Percutaneous Cardiovascular Interventions and Polish Cardiac Society

Mimo istotnego postępu w zmniejszeniu częstości restenozy i ponownych zabiegów rewaskularyzacyjnych przez stenty uwalniające leki antyproliferacyjne (DES, drug eluting stents) istnieją sprzeczne dane dotyczące podwyższonego ryzyka występowania późnej zakrzepicy w DES w porównaniu ze stentami metalowymi. Z pewnością wynika to z różnej skuteczności i bezpieczeństwa poszczególnych rodzajów DES, których liczba systematycznie się zwiększa. Ponadto ostatnio obserwuje się stopniowe zwiększenie dostępności DES, które nie osiągnęły pierwszorzędowych punktów końcowych w badaniach randomizowanych. Z tego powodu w przypadku DES nie można mówić o efekcie klasy. Niniejsze stanowisko stanowi analizę 110 randomizowanych badań klinicznych poświęconych DES, przeprowadzonych wśród 72 305 chorych. Cele niniejszego opracowania to usystematyzowanie wiedzy o DES oraz ocena wskazań do ich implantacji w rożnych sytuacjach klinicznych.Despite a dramatic reduction in restenosis and target vessel revascularisation rates by drug eluting stents (DES), conflicting concerns have been raised over the risk for late DES thrombosis when compared to bare metal stents. Certainly, the heterogeneity of DES results from the introduction of a great variety of new DES types with diverse efficacy and safety parameters. Furthemore, we observe a steady increase in DES availability without parallel and robust data from randomised clinical trials. Thus, the postulated class effect of DES should be regarded as nonobligatory. This article is based on 110 randomised DES trials performed on 72 305 patients. Current status of DES and guidelines for DES implantation in various clinical scenarios were discussed