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Clinical Screening Prediction in the Portuguese National Health Service: Data A...

This paper presents an analysis of the calls made to the Portuguese National Health Contact Center (SNS24) during a three years period. The final goal was to develop a system to help nurse attendants select the appropriate clinical pathway (from 59 options) for each call. It examines several aspects of the calls distribution like age and gender of the user, date and time of the call and final referral, among ot...

Effects of a mindfulness‑based intervention for teachers: a study on teacher an...

Impact of alkaline-acid and strongly acid process on the synthesis of urea-form...

This paper presents the impact of different processes for producing urea-formaldehyde resins and their roles on the physico-mechanical properties and the formaldehyde emission of the resulting particleboards. Five resins were produced: four via the alkaline-acid process (Resin A to D) and one using the strongly acid process (Resin E). The differences between the syntheses are mainly related to different formald...

Efeitos do programa Atentamente nos comportamentos dos professores em sala de aula

Impact of the Synthesis Procedure on Urea-Formaldehyde Resins Prepared by Alkal...

In this work, two synthesis procedures for the preparation of urea-formaldehyde (UF) resins, based on the alkaline-acid process, are studied in order to better understand the chemical reactions involved. For that purpose, the number of urea loads and the methyolation temperature were varied. The molecular weight distribution of the resins was monitored by gel permeation chromatography/size exclusion chromatogra...

Statistical evaluation of the effect of urea-formaldehyde resins synthesis para...

This work discusses the optimization of different synthesis parameters for a low emitting urea-formaldehyde (UF) resin. Industrially, this resin was synthesized using the alkaline-acid process (alkaline methylolation and acidic condensation) at different values of pH, temperature (T) and final viscosity and characterized according to different analytical methods. Particleboards (PBs) were produced using differe...

Utilization and characterization of amino resins for the production of wood-bas...

Particleboard (PB), medium density fibreboard (MDF), oriented strand board (OSB) and plywood (PW), the most common products of wood panel industry, are produced by means of synthetic adhesives (resins). From the wide range of adhesives employed, amino resins as combination of formaldehyde (F) and urea (U), and melamine (M) are the most important ones, which include the most popular UF and MUF resins. This revie...

Biocompatible reinforcement of poly(Lactic acid) with graphene nanoplatelets

A recently made available form of graphene nanoplatelets (GNP-C) is investigated for the first time as reinforcement filler for PLA. GNP-C, with thickness of about 2 nm and length 1-2 m, was incorporated at different loadings (0.1-0.5 wt%) in poly(lactic acid) (PLA) by melt blending. The effect of varying mixing time and mixing intensity was studied and the best conditions were identified, corresponding to mixi...

Smaller particle size and higher oxidation improves biocompatibility of graphen...

Graphene-based materials (GBMs) have recognized potential for biomedical applications, however different production methods and treatments originate divergent biocompatibility. In this work, two commercially available graphene nanoplatelets (GNP) were studied, differing in platelet size: GNP-C, with 1-2 mu m, and GNP-M, with 5 mu m. GNP-M was oxidized using KMnO4 in different ratios (1:3 and 1:6), leading to GN...

Preparation of amino resins and their impact on the production of wood-based pa...