Search results for "kuitu"

Ytterbium-doped fibers for high-power fiber lasers

2021

Ytterbium (Yb) doped optical fibers are widely used in high-power applications and ultrafast lasing since they show adequate power-handling capability and provide desirable beam quality. Yb-doped fibers with large core area can support high power but often act as a multimode fiber and compromise the output beam quality. Hence, it is important to attain a proper balance between the power-handling capability and the beam quality. Yb-doped fibers as a gain medium in pulsed fiber laser systems are prone to nonlinear optical effects due to the presence of high peak power in the ultrashort pulses. Nonlinearity such as self phase modulation (SPM) affects the width and the shape of the pulse, both …

Associations of nutrition and body composition with cardiovascular disease risk factors in soldiers during a 6-month deployment

2020

Objectives This observational follow-up study investigated the associations of nutrition and body composition with cardiovascular disease (CVD) risk factors, including pro-inflammatory biomarkers, in soldiers during a 6-month deployment. Material and Methods Thirty-five male soldiers were assessed at months 0, 3 and 6, and their parameters, i.e., M±SD, were as follows: age 30.0±8.7 years, height 179±6 cm, and BMI 24.2±2.5 kg/m 2 . Three-day food diaries were used for monitoring macronutrient intake. Body composition was estimated using bioimpedance. Fasting blood samples for lipids and pro-inflammatory biomarkers were collected, and blood pressure measurements were performed. Results Carboh…

Sleep-time physiological recovery is associated with eating habits in distressed working-age Finns with overweight: secondary analysis of a randomise…

2021

Background Association of physiological recovery with nutrition has scarcely been studied. We investigated whether physiological recovery during sleep relates to eating habits, i.e., eating behaviour and diet quality. Methods Cross-sectional baseline analysis of psychologically distressed adults with overweight (N = 252) participating in a lifestyle intervention study in three Finnish cities. Recovery measures were based on sleep-time heart rate variability (HRV) measured for 3 consecutive nights. Measures derived from HRV were 1) RMSSD (Root Mean Square of the Successive Differences) indicating the parasympathetic activation of the autonomic nervous system and 2) Stress Balance (SB) indica…

Kontrastin lisääminen puukuidun rakenteen selvittämiseksi ja paikallistamiseksi paperiarkista röntgentomografialla

2011

Pro gradu -tutkielman kirjallisuusosassa tavoitteena oli esitellä kemiallisia kontrastin lisäysmenetelmiä puukuitumateriaalille. Kontrastin lisäyksen tavoitteena on pystyä paikallistamaan kuitufraktioita, kuten nanoselluloosaa ja hienoainesta, paperiarkista röntgentomografiakuvauksen avulla. Kuidun eri kerrosten kontrastien lisääminen toisiin kerroksiin nähden auttaisi myös kuidun yksityiskohtaisen kerrosrakenteen määrittämisessä tomografiakuvantamisella, mikä on myös yhtenä tavoiteltavana kohteena. Alussa aihetta pohjustetaan kertomalla tomografiasta materiaalin rakenteen tutkimusmenetelmänä ja syvennytään ymmärtämään kuidun monimutkaista rakennetta. Merkintä- ja värjäysmenetelmiä käydään …

Effect of aerobic exercise and diet on liver fat in pre-diabetic patients with non-alcoholic-fatty-liver-disease: A randomized controlled trial.

2017

AbstractThe study aimed to assess whether aerobic exercise (AEx) training and a fibre-enriched diet can reduce hepatic fat content (HFC) and increase glycaemic control in pre-diabetic patients with non-alcoholic fatty liver disease (NAFLD). Six-hundred-and-three patients from seven clinics in Yangpu district, Shanghai, China were recruited. Of them 115 individuals aged 50–65-year fulfilled the inclusion criteria (NAFLD with impaired fasting glucose or impaired glucose tolerance) and were randomly assigned into exercise (AEx n = 29), diet (Diet n = 28), exercise plus diet (AED n = 29), or no-intervention (NI n = 29) groups. Progressive supervised AEx training (60–75% VO2max intensity) was gi…

Optical Fiber Based Dosimeter Data From RADEF Pulsed Electron Beams - Oscilloscope Traces

2021

These data are from tests of fiber optic based dosimetry systems. The purpose of the collected data is to use it for characterizing the different tested samples responses against pulsed electron radiation, for different electron bunch sizes. The tested samples are sol-gel silica glass rods doped with Ce, Cu, or Gd ions, making the rods radioluminescent. The samples were connected to a multimode pure-silica core optical fiber, which transported the radiation induced luminescence (RIL) to a photomultiplier tube (PMT) with an optical band pass filter in front of it. The samples were subject to a pulsed 20 MeV electron beam. The resulting output pulses from the PMT from the induced RIL light we…

Puukuitususpension putkivirtauksen virtausprofiilin symmetrisyys ja sen turbulenttisen alueen mallintaminen

2007

Pääoma hakkuuaukealla

2022

Metsien hiilensidonta on keskeinen kysymys ekologisessa siirtymässä, ja metsäekologioiden ja biodiversiteetin tilaa olisi kohennettava kiireisesti. Toisaalla metsäresurssien odotetaan toimivan materiaalisena pohjana uudelle vihreän kasvun biotaloussyklille. Samalla metsäteollisuuden kannattavuus on laskussa ja sen materiaalinen läpivirtaama on kasvanut. Tähän tilanteeseen johtaneita kehityskulkuja selitetään tässä artikkelissa kuitupuukapitalismiksi kutsumamme metsätalouden tendenssin avulla. Tarkastelemme kuitupuukapitalismia James C. Scottin luettavuuden (legibility) käsitteen sekä voiton suhdeluvun laskutendenssin teorian kautta. Esitämme historiallisen tarkastelun pohjalta, että kuritto…

Structural characterisation of wood pulp fibres and their nanofibrillated materials for biodegradable composite applications

2011

Introduction: The utilization of wood pulp fibres in composite materials has gained major interest during the last years. One of the major motivations has been the potential of wood pulp fibres and their nanofibrillated derivatives for increasing the mechanical properties of some materials. However, in order to exploit the full potential of wood pulp fibres and cellulose nanofibrils as reinforcement in hydrophilic and hydrophobic matrices, several characteristics of fibres and their interactions with a given matrix need to be understood. With the increasing capabilities of novel microscopy techniques and computerized image analysis, structural analysis is moving forward from visual and subj…