Search results for "infrapunasäteily"
showing 8 items of 8 documents
NIR-absorbing transition metal complexes with redox-active ligands
2020
Bench top stable transition metal (M = Co, Ni, Cu) complexes with a non-innocent ortho-aminophenol derivative were synthesized by the reaction of metal(II)acetates with a ligand precursor in 2:1 ratio. The solid-state structures reveal the formation of neutral molecular complexes with square planar coordination geometries. The Co(II) and Cu(II) complexes are paramagnetic, whereas the Ni complex is a diamagnetic square planar low-spin Ni(II) complex. All complexes, and Ni(II) complex in particular, show strong absorption in the near-IR region. Peer reviewed
Transient IR spectroscopy identifies key interactions and unravels new intermediates in the photocycle of a bacterial phytochrome.
2020
Phytochromes are photosensory proteins in plants, fungi, and bacteria, which detect red- and far-red light. They undergo a transition between the resting (Pr) and photoactivated (Pfr) states. In bacterial phytochromes, the Pr-to-Pfr transition is facilitated by two intermediate states, called Lumi-R and Meta-R. The molecular structures of the protein in these states are not known and the molecular mechanism of photoconversion is not understood. Here, we apply transient infrared absorption spectroscopy to study the photocycle of the wild-type and Y263F mutant of the phytochrome from Deinococcus radiodurans (DrBphP) from nanoto milliseconds. We identify two sequentially forming Lumi-R states …
Vibrational Spectrum of HXeSH revisited : Combined computational and experimental study
2020
Vibrational spectrum of HXeSH embedded in low-temperature matrix is experimentally studied. To support the spectrum interpretation, anharmonic vibrational analysis is performed using different models and basis sets and the data is compared with previous experimental and theoretical analyses. Computations of overtones and combination modes allowed for new band assignments. The HXeSH molecule exhibits high anharmonicity similarly as other molecules from the noble-gas hydride family. Comparison of the employed computational methods shows once again that the modelling of the noble-gas compounds faces theoretical challenges to yield quantitatively reliable results. peerReviewed
A post-exercise infrared sauna session improves recovery of neuromuscular performance and muscle soreness after resistance exercise training
2023
The aim of this study was to investigate effects of a single infrared sauna (IRS) session on postexercise recovery of neuromuscular performance, autonomic nervous system function, subjective sleep quality, and muscle soreness. Male basketball players (n = 16) performed two trials consisting of a complex resistance exercise protocol (maximal strength with plyometrics), followed by either 20 min passive recovery (PAS) or IRS (temperature 43±5°C), in a randomized crossover design, with trials separated by one week. Recovery of neuromuscular performance was assessed using 20 m maximal sprint, maximal countermovement-jump (CMJ), and isometric leg press tests, performed 14 hours after exercise. H…
Electronic and vibrational spectroscopic studies of gold-nanoclusters
2016
Gold nanoclusters are a peculiar new material with properties between that of bulk metal and single atoms. They show size-dependent evolution of optical and electronic properties sensitive to the change of single atom or single electron in the system. Understanding the relationship between structure and properties is important to both fundamental scientific question of the role of the quantum size effects in small metal-clusters, and to application of nanoclusters in e.g. photonics, nanoelectronics, and heterogeneous catalysis. In this thesis four spectroscopic studies of monolayer-protected gold-nanoclusters are presented. The optical gap of the Au144(PET)60 and (Au/Ag)144(PET)60 (PET: pheny…
Photodynamics studies of ligand-protected gold nanoclusters by using ultrafast transient infrared spectroscopy
2015
Highly monodisperse samples of three ligand-protected gold nanoclusters Au102(pMBA)44, Au144(SC2H4Ph)60, and a cluster tentatively identified as Au130(pMBA)50, were characterized by UV/vis and infrared spectroscopy, and their photodynamics was studied by transient absorption spectroscopy. The dynamics study for each cluster was performed by electronically exciting the cluster with a pump pulse in the visible or near infrared region and by monitoring the transient absorption of vibrational modes of the ligands with a mid-IR probe pulse. The photodynamics studies were used to determine the molecular or metallic behavior of the cluster, and also to gain important size dependent information abo…
Infrapunapussin vaikutus urheilijan palautumiseen yösykeanalyysien perusteella
2012
Johdanto. Palautuminen kovasta harjoittelusta ja erityisesti palautumisen tehostaminen on tärkeässä osassa huippu-urheilua. Infrapunasäteily on yksi uusimmista keinoista palautumisen tehostamisessa. Infrapunasäteilyn lämpövaikutukset ulottuvat syvemmälle lihaksiin verrattuna muihin lämpöterapiamuotoihin. (Beever 2009.) Tutkimuksen tarkoituksena oli selvittää infrapunapussin (FIR 65° Energy Blanket) käytön hyötyjä urheilijoiden palautumisen edistämisessä yösykeanalyysien perusteella. Menetelmät. Koehenkilöinä (n=8) oli yleisurheilua, pesäpalloa ja telinevoimistelua harrastavia urheilijoita (ikä 21,1 ± 2,3 vuotta, pituus 178,1 ± 6,6 cm ja paino 76,8 ± 10 kg). Harjoittelu suunniteltiin mukana …
Adolf von Beckerin identtiset Ateljeessa-maalaukset – aitoja, kopioita vai väärennöksiä?
2021
Artikkelissa esittelemme kahden Adolf von Beckerin nimiin signeeratun Ateljeessa-teoksen tutkimusta taidehistorian, maalaustekniikan ja materiaalitutkimuksen näkökulmista. Samalla pyrimme tuomaan esiin mitä uutta moniammatillinen yhteistyö ja luonnontieteessä käytetyt menetelmät on tuoneet taideteosten tutkimukseen. Tutkimuksessa voitiin osoittaa, että toinen teoksista on alkuperäinen ja toinen on kopio siitä. Kopion maalaajaksi osoittautui Hilda Granstedt. Tutkimusmenetelminä käytettiin perinteisen arkistotutkimuksen lisäksi erilaisia sähkömagneettista säteilyä tallentavia kuvantamismenetelmiä, kuten röntgen-, ultravioletti- ja infrapunareflektiokuvausta, sekä materiaalianalyyttisiin menet…