Search results for "general [BL Lacertae objects]"

Oxidation-responsive and "clickable" poly(ethylene glycol) via copolymerization of 2-(methylthio)ethyl glycidyl ether

2016

Poly(ethylene glycol) (PEG) is a widely used biocompatible polymer. We describe a novel epoxide monomer with methyl-thioether moiety, 2-(methylthio)ethyl glycidyl ether (MTEGE), which enables the synthesis of well-defined thioether-functional poly(ethylene glycol). Random and block mPEG-b-PMTEGE copolymers (Mw/Mn = 1.05-1.17) were obtained via anionic ring opening polymerization (AROP) with molecular weights ranging from 5 600 to 12 000 g·mol-1. The statistical copolymerization of MTEGE with ethylene oxide results in a random microstructure (rEO = 0.92 ± 0.02 and rMTEG E = 1.06 ± 0.02), which was confirmed by in situ 1H NMR kinetic studies. The random copolymers are thermorespon…

Tunable Interaction Strength and Nature of the S···Br Halogen Bonds in [(Thione)Br2] Systems

2015

The strength and nature of the S···Br and Br···Br interactions were systematically tuned by altering the electron donor properties of the thione group. Three new halogen-bonded compounds, [(N-methylbenzothiazole-2-thione)Br2]·0.5CH2Cl2 (1), [(2(3H)-benzothiazolethione)Br2] (2), and [(2-benzimidazolethione)Br]·[Br3] (3), were synthesized and studied structurally by using X-ray crystallography and computationally by using charge density analysis based on QTAIM calculations. Analysis of the interaction strength indicated a formation of surprisingly strong S···Br halogen bonds in 1 (−104 kJ mol–1, and RBrS = 0.64) and 2 (−116 kJ mol–1, and RBrS = 0.63) with a substantial covalent contribution. …

Investigation of Nonlinear Optical Processes in Mercury Sulfide Quantum Dots

2022

European Regional Development Fund (1.1.1.5/19/A/003), State Assignment to Higher Educational Institutions of Russian Federation (FZGU-2020-0035), Russian Foundation for Basic Research (18-29-20062). Institute of Solid State Physics, University of Latvia as the Center of Excellence acknowledges funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2.

Samtal om Budkavlen : hågkomster från 1970–1990-talen

2022

Med anledning av Budkavlens 100-årsjubileum fick jag i uppdrag att intervjua två av tidskriftens tidigare medarbetare – professor emeritus Nils Storå och intendent John Hackman – om deras erfarenheter av utgivningen av tidskriften under 1970–1990-talen. Nils Storå (f. 1933) var professor i nordisk etnologi under åren 1972–1997 och John Hackman (f. 1942) var amanuens vid Sjöhistoriska museet 1972–1975 och därefter intendent vid Etnologiska institutionen fram till sin pensionering 2005. Texten nedan ger en bild av hur det var att driva en humanistisk vetenskaplig tidskrift under 1900-talets sista decennier. Samtalet som återges är fiktivt i den meningen att jag valt att placera mina frågor oc…

Modernin tieteen rajapinnoilla : kaksi teosta tieteellisen vallankumouksen aikakaudelta

2011

Filosofia tutkielmia / Gottfried Wilhelm Leibniz ; toimittaneet Tuomo Aho ja Markku Roinila ; suomentajat Tuomo Aho ... ja muita. Helsinki : Gaudeamus Helsinki University Press, 2011. 511 s. ISBN 978-952-495-121-0 Modernin tieteen synty Euroopassa / Paolo Rossi ; suomentanut Lena Talvio. Tampere : Vastapaino, 2010. 395 s. ISBN 978-951-768-153-7

Konstruktivismi on vaarallista!

2023

Bending Work Time: Curvilinear Relationship Between Working Time Dimensions and Psychological and Somatic Symptoms.

2020

Objectives Study examines the curvilinear associations of working time dimensions (working hours, time pressure, work schedules, and control of work time and pace) on psychological and somatic symptoms. Methods Representative Finnish Quality-of-Work-Life Surveys conducted in 2003, 2008 and 2013 were restricted to those (N=11,165) regularly working over 10h/week with more than one-year tenure in their job. Generalised additive models were utilised in analysis. Results Working hours had U-shaped relationships with psychosomatic symptoms, while time pressure had a threshold effect. Work pace control had linear effect. The effects of work time control and work schedules were insignificant. Ther…

Estimation of the Time-Variant Velocity of a Single Walking Person in Two-Dimensional Non-Stationary Indoor Environments Using Radio-Frequency Techni…

2020

Accurate estimation of the time-variant (TV) velocity of moving persons/objects in indoor spaces is of crucial importance for numerous wireless indoor applications. This article introduces a novel iterative procedure to estimate the TV velocity, i.e., TV speed and TV angle-of-motion (AOM), of a single moving person in 2D indoor environments by using radio-frequency (RF) techniques. The indoor area is equipped with a distributed 2 × 2 multiple-input multiple-output (MIMO) system. The proposed method is divided into two parts. In the first part, we estimate the path gains and the instantaneous Doppler frequencies by fitting the exact spectrograms of the complex channel gains of a 2D no…

Structural distortions in homoleptic (RE)4A (E = O, S, Se; A = C, Si, Ge, Sn): Implications for the CVD of tin sulfides

2001

The structures of Sn(SBut)4 and Sn(SCy)4 have been determined and adopt S4 and D2 conformations respectively; the anion [(PhS)Sn3]−, as its Ph4P+ salt, has a structure approaching Cs symmetry. In all three compounds, there are large variations in the ∠S–Sn–S within the same molecule, which have been rationalised in terms of the C–S–Sn–S–C conformations. For Sn(SR)4, the ∠S–Sn–S increases as the conformations change from trans, trans to trans, gauche and gauche, gauche, as the number of eclipsed lone pairs decreases and this rationale is shown to be applicable to a variety of A(ER)4 (A = C, Si, Ge, Sn; E = O, S, Se) and related [Mo(SR)4, Ga(SR)4−] systems. AM1 calculations have been used to …

Deposition of tin sulfide thin films from tin(iv) thiolate precursors

2001

AACVD (aerosol-assisted chemical vapour deposition) using (PhS)(4)Sn as precursor leads to the deposition of Sn3O4 in the absence of H2S and tin sulfides when H2S is used as co-reactant. At 450 degreesC the film deposited consists of mainly SnS2 while at 500 degreesC SnS is the dominant component. The mechanism of decomposition of (PhS)(4)Sn is discussed and the structure of the precursor presented.