diamond drilling of carbon fiber reinforced polymers influence of tool grit size and process parameters on workpiece delamination

Abstract The physical and mechanical properties of advanced composite materials promote their application in structural components for the aerospace and automotive sectors. However, limitations in their machinability are due to anisotropy/inhomogeneity, poor plastic deformation, and abrasive behavior. For CFRP drilling, the process efficiency is heavily influenced by cutting conditions and tool geometry. This paper reports the outcomes of experimental diamond drilling tests. A 4-mm thick carbon-epoxy composite laminate was machined. The plate was made of ten layers, in which the carbon fibers were intertwined at 90°. 6-mm diameter core drills were used. Core drills were characterized by an electroplated bond type and an AC32-H diamond grain type. Four different tool grit size ranges were tested: (1) 63/53 μm, (2) 125/106 μm, (3) 212/180 μm, and (4) 212/180 plus 63/53 μm. The results are reported in terms of workpiece delamination, thrust force, torque, and chip morphology. Overall, the results allow identifying the cutting conditions for the minimum drilling-induced delamination while retaining a satisfactory process productivity

Milling and Turning of Titanium Aluminides by Using Minimum Quantity Lubrication

AbstractWhen machining difficult-to-cut materials, the high temperature in the cutting area is one of the dominating phenomena affecting tool wear and process capability. Hence, cutting fluids are profusely used for cooling and lubrication purposes, in order to obtain satisfactorily process performances. The use of conventional fluids creates several problems, such as the environmental pollution due to chemical disassociation at high cutting temperatures, water pollution, soil contamination during disposal, and biological problems to operators. The implementation of green machining strategies to accomplish the increasing pressures for sustainability is therefore an open challenge for manufacturers and researchers. Aim of this paper is to evaluate the influence of the lubrication strategy on tool wear, surface quality and environmental impact when milling and turning Ti-48Al-2Cr-2Nb (at. %) intermetallic alloys. The workpieces were obtained by means of two production processes: vacuum arc remelting and electron beam melting (EBM). Coated carbide tools were used in cutting tests under different lubrication conditions. The results of dry cutting are compared to that of wet and minimum quantity lubrication (MQL) conditions. Overall, the experimental tests show that dry machining requires a sensible reduction of process parameters to preserve a stable process, although limiting the energy consumption and reducing to zero the lubricant consumption. Under the chosen cutting conditions, MQL appears to be an advantageous solution for milling, whilst in turning wet cutting is the best choice for reducing the tool wear, since the higher process temperatures require the higher cooling effect of the emulsion

How do cardiologists select patients for dual antiplatelet therapy continuation beyond 1 year after a myocardial infarction? Insights from the EYESHOT Post-MI Study

Background: Current guidelines suggest to consider dual antiplatelet therapy (DAPT) continuation for longer than 12 months in selected patients with myocardial infarction (MI). Hypothesis: We sought to assess the criteria used by cardiologists in daily practice to select patients with a history of MI eligible for DAPT continuation beyond 1 year. Methods: We analyzed data from the EYESHOT Post-MI, a prospective, observational, nationwide study aimed to evaluate the management of patients presenting to cardiologists 1 to 3 years from the last MI event. Results: Out of the 1633 post-MI patients enrolled in the study between March and December 2017, 557 (34.1%) were on DAPT at the time of enrolment, and 450 (27.6%) were prescribed DAPT after cardiologist assessment. At multivariate analyses, a percutaneous coronary intervention (PCI) with multiple stents and the presence of peripheral artery disease (PAD) resulted as independent predictors of DAPT continuation, while atrial fibrillation was the only independent predictor of DAPT interruption for patients both at the second and the third year from MI at enrolment and the time of discharge/end of the visit. Conclusions: Risk scores recommended by current guidelines for guiding decisions on DAPT duration are underused and misused in clinical practice. A PCI with multiple stents and a history of PAD resulted as the clinical variables more frequently associated with DAPT continuation beyond 1 year from the index MI

Effects of Anacetrapib in Patients with Atherosclerotic Vascular Disease

BACKGROUND: Patients with atherosclerotic vascular disease remain at high risk for cardiovascular events despite effective statin-based treatment of low-density lipoprotein (LDL) cholesterol levels. The inhibition of cholesteryl ester transfer protein (CETP) by anacetrapib reduces LDL cholesterol levels and increases high-density lipoprotein (HDL) cholesterol levels. However, trials of other CETP inhibitors have shown neutral or adverse effects on cardiovascular outcomes. METHODS: We conducted a randomized, double-blind, placebo-controlled trial involving 30,449 adults with atherosclerotic vascular disease who were receiving intensive atorvastatin therapy and who had a mean LDL cholesterol level of 61 mg per deciliter (1.58 mmol per liter), a mean non-HDL cholesterol level of 92 mg per deciliter (2.38 mmol per liter), and a mean HDL cholesterol level of 40 mg per deciliter (1.03 mmol per liter). The patients were assigned to receive either 100 mg of anacetrapib once daily (15,225 patients) or matching placebo (15,224 patients). The primary outcome was the first major coronary event, a composite of coronary death, myocardial infarction, or coronary revascularization. RESULTS: During the median follow-up period of 4.1 years, the primary outcome occurred in significantly fewer patients in the anacetrapib group than in the placebo group (1640 of 15,225 patients [10.8%] vs. 1803 of 15,224 patients [11.8%]; rate ratio, 0.91; 95% confidence interval, 0.85 to 0.97; P=0.004). The relative difference in risk was similar across multiple prespecified subgroups. At the trial midpoint, the mean level of HDL cholesterol was higher by 43 mg per deciliter (1.12 mmol per liter) in the anacetrapib group than in the placebo group (a relative difference of 104%), and the mean level of non-HDL cholesterol was lower by 17 mg per deciliter (0.44 mmol per liter), a relative difference of -18%. There were no significant between-group differences in the risk of death, cancer, or other serious adverse events. CONCLUSIONS: Among patients with atherosclerotic vascular disease who were receiving intensive statin therapy, the use of anacetrapib resulted in a lower incidence of major coronary events than the use of placebo. (Funded by Merck and others; Current Controlled Trials number, ISRCTN48678192 ; ClinicalTrials.gov number, NCT01252953 ; and EudraCT number, 2010-023467-18 .)

Metodologie e sperimentazioni turistico-culturali per la qualit\ue0 della vita. La realizzazione di itinierari transnazionali e di percorsi locali

Lo scritto si riferisce alla ricerca interuniversitaria internazionale "Routes for Tourism and Culture" (2001-2003), soffermadosi in dettaglio sugli stadi di avanzamento e sulle ulteriori applicazioni relative al turismo assistito con tecniche multimediali

L'approvvigionamento idropotabile nella provincia di Vicenza.

Pubbl. Istituto di Geografia, Facolt\ue0 di Economia e Commercio

Routes for Tourism and Culture. Una ricerca internazionale e le ricadute a livelllo locale

Presentazione del lavoro effettuato dal gruppo di ricerca internazionale "Routes for tourism and culture", con le ricadute e i collegamenti messi in atto dall'Unit\ue0 di Verona e di Macerata in seguito alle attivit\ue0 svolte. In particolare con istituzioni, enti, associazioni e privati