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Homoaggregates of isocyanic acid (HNCO) were studied using FTIR spectroscopy combined with a low-temperature matrix isolation technique and quantum chemical calculations. Computationally, the structures of the HNCO dimers and trimers were optimized at the MP2, B3LYPD3 and B2PLYPD3 levels of theory employing the 6-311++G(3df,3pd) basis set. Topological analysis of the electron density (AIM) was used to identify the type of non-covalent interactions in the studied aggregates. Five stable minima were located on the potential energy surface for (HNCO)2, and nine were located on the potential energy surface for (HNCO)3. The most stable dimer (D1) involves a weak, almost linear N-H⋯N hydrogen bond. Other structures are bound by a N-H⋯O hydrogen bond or by O⋯C or N⋯N van der Waals interactions. Similar types of interactions as in (HNCO)2 were found in the case of HNCO trimers. Among nine stable (HNCO)3 structures, five represent cyclic forms. The most stable T1 trimer structure is characterized by a six-membered ring formed by three N-H⋯N hydrogen bonds and representing high symmetry (C3h). The analysis of the HNCO/Ar spectra after deposition indicates that the N-H⋯O hydrogen-bonded dimers are especially prevalent. Upon annealing, HNCO trimers were observed as well. Identification of the experimentally observed species relied on previous experimental data on HNCO complexes as well as computed data on HNCO homoaggregates’ vibrational spectra.

We report on a study of the α-decay fine structure and the associated Eα−Eγ correlations in the decays of 171,172Os and 171,172,174Ir. In total, 13 new α-decay energy lines have been resolved, and three new γ-ray transitions have been observed following the new decay branches to 168Re and 167W. The weak α-decay branch from the bandhead of the νi13/2 band in 171Os observed in this work highlights an unusual competition between α, β, and electromagnetic decays from this isomeric state. The nucleus 171Os is therefore one of few nuclei observed to exhibit three different decay modes from the same excited state. The nuclei of interest were produced in 92Mo(83Kr,xpyn) fusion-evaporation reactions at the Accelerator Laboratory of the University of Jyväskylä, Finland. The fusion products were selected using the gas-filled ion separator RITU and their decays were characterized using an array of detectors for charged particles and electromagnetic radiation known as GREAT. Prompt γ-ray transitions were detected and correlated with the decays using the JUROGAM II germanium detector array surrounding the target position. Results obtained from total Routhian surface (TRS) calculations suggest that α-decay fine structure and the associated hindrance factors may be a sensitive probe of even relatively small shape changes between the final states in the daughter nucleus. peerReviewed

openaire: EC/H2020/788185/EU//E-DESIGN Two-dimensional magnetic materials provide an ideal platform to explore collective many-body excitations associated with spin fluctuations. In particular, it should be feasible to explore, manipulate, and ultimately design magnonic excitations in two-dimensional van der Waals magnets in a controllable way. Here we demonstrate the emergence of moiré magnon excitations, stemming from the interplay of spin-excitations in monolayer CrBr3 and the moiré pattern arising from the lattice mismatch with the underlying substrate. The existence of moiré magnons is further confirmed via inelastic quasiparticle interference, showing the appearance of a dispersion pattern correlated with the moiré length scale. Our results provide a direct visualization in real-space of the dispersion of moiré magnons, demonstrating the versatility of moiré patterns in creating emergent many-body excitations.

The design of soft biomaterials requires a deep understanding of molecular self-assembly. We introduce here a nanoscale infrared (IR) spectroscopy study of a two-component supramolecular gel to assess the system´s heterogeneity and supramolecular assembly. In contrast to far-field IR spectroscopy, near-field IR spectroscopy revealed differences in the secondary structures of the gelator molecules and non-covalent interactions at three distinct nano-locations of the gel network. A β-sheet arrangement is dominant in single and parallel fibres with a small proportion of an α-helix present, while the molecular assembly derives from strong hydrogen bonding. However, at the crossing point of two fibres, only the β-sheet motif is observed, with an intense π-π stacking contribution. Near-field nanospectroscopy can become a powerful tool for the nanoscale distinction of non-covalent interactions, while is expected to advance the existing spectroscopic assessments of supramolecular gels. peerReviewed

A recoil-beta-tagging experiment has been per formed to study the excited T = 0 and T = 1 states in the odd–odd N = Z nucleus 94Ag, populated via the 40Ca(58Ni,1p3n)94Ag reaction. The experiment was con ducted using the MARA recoil separator and JUROGAM3 array at the Accelerator Laboratory of the University of Jyväskylä. Through correlating fast, high-energy beta decays at the MARA focal plane with prompt γ rays emitted at the reaction target, a number of transitions between excited states in 94Ag have been identified. The timing characteris tics of these transitions confirm that they fall within decay sequences that feed the short-lived T = 1 ground state of 94Ag. The transitions are proposed to proceed within and between the sets of states with T = 0 and T = 1. Possi ble correspondence between some of these transitions from analog states in 94Pd has been discussed, and shell-model cal culations including multipole and monopole electromagnetic effects have been presented, in order to enable predictions of the decay patterns between the T = 0 and T = 1 states and to allow a theoretical set of Coulomb energy differences to be calculated for the A = 94 T = 1 analog states. peerReviewed

Nuclear instruments & methods in physics research / B 540, 148 - 150 (2023). doi:10.1016/j.nimb.2023.04.021, Published by Elsevier, Amsterdam [u.a.]

Signal propagation in photosensory proteins is a complex and multidimensional event. Unraveling such mechanisms site-specifically in real time is an eligible but a challenging goal. Here, we elucidate the site-specific events in a red-light sensing phytochrome using the unnatural amino acid azidophenylalanine, vibrationally distinguishable from all other protein signals. In canonical phytochromes, signal transduction starts with isomerization of an excited bilin chromophore, initiating a multitude of processes in the photosensory unit of the protein, which eventually control the biochemical activity of the output domain, nanometers away from the chromophore. By implementing the label in prime protein locations and running two-color step-scan FTIR spectroscopy on the Deinococcus radiodurans bacteriophytochrome, we track the signal propagation at three specific sites in the photosensory unit. We show that a structurally switchable hairpin extension, a so-called tongue region, responds to the photoconversion already in microseconds and finalizes its structural changes concomitant with the chromophore, in milliseconds. In contrast, kinetics from the other two label positions indicate that the site-specific changes deviate from the chromophore actions, even though the labels locate in the chromophore vicinity. Several other sites for labeling resulted in impaired photoswitching, low structural stability, or no changes in the difference spectrum, which provides additional information on the inner dynamics of the photosensory unit. Our work enlightens the multidimensionality of the structural changes of proteins under action. The study also shows that the signaling mechanism of phytochromes is accessible in a time-resolved and site-specific approach by azido probes and demonstrates challenges in using these labels. peerReviewed

Four bis(O–I–N) compounds have been synthesised from various dihypoiodites and 4-ethylpyridine. The compounds were characterised in both the solution and solid states by NMR spectroscopy (1H, 15N), X-ray diffraction, and computational calculations. peerReviewed

Graphene is not intrinsically luminescent, due to a lack of bandgap, and methods for its creation are tricky for device fabrication. In this study, we create luminescent graphene patterns by a simple direct laser writing method. We analyze the graphene using Raman spectroscopy and find that the laser writing leads to generation of line defects after initial formation of point defects. This Raman data enables us to create a model that explains the luminescence by a formation of small domains due to confinement of graphene by line defects, which is conceptually similar to the mechanism of luminescence in graphene quantum dots. peerReviewed

Raman spectroscopy offers a nondestructive means to identify minerals in rocks, but the ability to use the technology for quantitative mineralogical analysis is limited by fluorescence that can mask the spectral features of minerals. In this paper we apply continuous wavelet transformation (CWT) to remove fluoresence from Raman data acquired from 26 carbonate rock samples. We then record the intensity values of individual spectral features, proxies for mineral abundances, using the original Raman data and the thus inferred CWT data. The intensity values are then compared against the known mineral abundances determined using the scanning electron microscope (SEM) technology. This comparison is conducted using a linear regression model to determine whether fluorescence removal enhances the mineral abundance predictions. Our results suggest that CWT enhances the accuracy of mineral abundance estimates, thus highlighting the importance of fluorescence removal when using Raman for quantitative mineralogical analysis. peerReviewed

© 2019 The CRIS experiment at CERN-ISOLDE is a dedicated laser spectroscopy setup for high-resolution hyperfine structure measurements of nuclear observables of exotic isotopes. Between 2015 and 2018 developments have been made to improve the background suppression, laser-atom overlap and automation of the beamline. Furthermore, a new ion source setup has been developed for offline studies. Here we present the latest technical developments and future perspectives for the experiment. ispartof: Nuclear Instruments & Methods In Physics Research Section B-Beam Interactions With Materials And Atoms vol:463 pages:384-389 ispartof: location:SWITZERLAND, CERN, Geneva status: published

The selenium isotopes lie at the heart of a tumultuous region of the nuclear chart where shape coexistence effects grapple with neutron-proton pairing correlations, triaxiality, and the impending proton drip line. In this work, a study of 72Se by internal conversion electron and γ-ray spectroscopy was undertaken with the SPICE and TIGRESS arrays. New measurements of the branching ratio and lifetime of the 02+ state were performed, yielding a determination of ρ2(E0;02+→01+)=29(3) milliunits. Two-state mixing calculations were performed that highlighted the importance of interpretation of such E0 strength values in the context of shape coexistence. peerReviewed

The Complete Calibration of the Color–Redshift Relation survey (C3R2) is a spectroscopic program designed to empirically calibrate the galaxy color–redshift relation to the Euclid depth (IE = 24.5), a key ingredient for the success of Stage IV dark energy projects based on weak lensing cosmology. A spectroscopic calibration sample that is as representative as possible of the galaxies in the Euclid weak lensing sample is being collected, selecting galaxies from a self-organizing map (SOM) representation of the galaxy color space. Here, we present the results of a near-infrared H- and K-band spectroscopic campaign carried out using the LUCI instruments at the LBT. For a total of 251 galaxies, we present new highly reliable redshifts in the 1.3 ≤ z ≤ 1.7 and 2 ≤ z ≤ 2.7 ranges. The newly-determined redshifts populate 49 SOM cells that previously contained no spectroscopic measurements and almost twice the occupation numbers of an additional 153 SOM cells. A final optical ground-based observational effort is needed to calibrate the missing cells, in particular in the redshift range 1.7 ≤ z ≤ 2.7, which lack spectroscopic calibration. In the end, Euclid itself will deliver telluric-free near-IR spectra that can complete the calibration. peerReviewed

Laserspektroskopiset menetelmät ovat nopeita ja tehokkaita mineraalitutkimuksen keinoja, koska analyysi voidaan tehdä suoraan näytteen pinnalta ja jopa metrien päästä kohteesta. Nykyteknologian ansiosta laserspektroskopian laitteistoja voidaan lisäksi miniatyrisoida, ja siten ne soveltuvat etämittauksiin esimerkiksi maastossa, linjastolla tai kaivoksessa (in situ). Tässä artikkelissa esitellään laserindusoitu plasmaspektroskopia (LIBS), laser-indusoitu luminesenssispektroskopia ja Raman-spektroskopia, joilla saadaan näytteistä toisiaan täydentävää informaatiota (Romppanen 2021). Tunnetuimmat esimerkit laserspektroskopian soveltuvuudesta mineraalianalytiikassa löytyvät Marsista, sillä planeetalla vuodesta 2012 toimineessa Nasan Curiositymönkijän ChemCam-laitteistossa on LIBS-analysaattori ja viime vuonna laskeutuneen Perseverancen SuperCam-laitteistoon valittiin etämittauksiin soveltuvat LIBS- ja Raman-spektrometrit. nonPeerReviewed

The excited-state properties of an amphiphilic porphyrin–fullerene dyad and of its porphyrin analogue adsorbed at the dodecane/water interface are investigated by using surface second-harmonic generation. Although the porphyrin is formally centrosymmetric, the second-harmonic spectra of both compounds are dominated by the intense Soret band of the porphyrin. Polarization-selective measurements and molecular dynamics simulations suggest an angle of about 45° between the donor–acceptor axis and the interfacial plane, with the porphyrin interacting mostly with the nonpolar phase. Time-resolved measurements reveal a marked concentration dependence of the dynamics of both compounds upon Q-band excitation, indicating the occurrence of intermolecular quenching processes. The significant differences in dynamics and spectra between the dyad and the porphyrin analogue are explained by a self-quenching of the excited dyad via an intermolecular electron transfer. peerReviewed

Simultaneously sampling prism and grating-based spectrograph solutions for portable hyper-spectral LIDAR (Light Detection and Ranging) applications are compared in this thesis. Hyper-spectral LIDARs (HSL) are laser-based devices that are used in remote sensing and detection, as they obtain spectral and spatial information simultaneously. HSLs operate in a wide spectral range and are often used with supercontinuum laser sources as they produce a very broad spectral band of light. In this thesis, a HSL designed and provided by the Finnish Geospatial Research Institute (FGI) is used and studied. The spectrograph solutions are compared to each other, and some software-based solutions, such as Fraunhofer approximation (FA) and Rigorous Coupled Wave Analysis (RCWA) along with the data provided by manufacturers. The main three aspects that are studied are efficiency, resolution, and size of the overall solution. The HSL instrument obtains spectral and spatial information simultaneously from the environment. The spectrum is measured using a diffractive optical element (DOE) that separates the different wavelengths spatially. Before the spectrum is guided into the DOE it enters a slit and is collimated either with a lens or a mirror. After the DOE has spread the spectrum, the light is focused with a lens or mirror element. Subsequently, the radiation is detected by either a flux or an image detector. The measurement setup for this project was executed to study how the DOE operates. The key point of this thesis is to compare these solutions to find out which would be the best possible element for the final HSL application. The software solutions should be investigated more to achieve realistic results. Some errors were detected due to the material properties and unfamiliar geometry of the optical element. The data provided by the manufacturers corresponded well to the measurement result, unlike the software solutions that evaluated well only the efficiency peaks of the gratings. Comparing different optical elements’, the prism had the best spectral efficiency as compared to gratings. However, the prism’s disadvantage is its dispersion, which has a considerable impact on the overall response. When comparing different grating solutions, no major differences were seen. The only disadvantage compared to the prism was the overlapping that gratings have. An additional spectrograph solution was introduced in this thesis, which was a combination of optical filter, prism, and grating. This lays the groundwork for future solutions. In the application, it was noticed that the sensor’s number of channels is the limiting factor of resolution. The light source and the detector are components that notably affect the response of the application. Therefore, the DOE should be selected to have the efficiency peak where the sensor or light source is not that sensitive.

Funding Information: This work was supported by Academy of Finland grants 285461 (H.T.), 330678 (H.T., J.R.), 277194 (H.L.), and 290677 (S.M.). We acknowledge the European Synchrotron Radiation Facility (ESRF) for providing synchrotron access for crystal data collection. We thank Prof. Janne Ihalainen (University of Jyväskylä) for all the help in all aspects of the paper, Prof. Gerrit Groenhof (University of Jyväskylä) for support, and Prof. Nikolai V. Tkachenko (Tampere University) for help and facilities for time-resolved absorption spectroscopy. We also thank M.Sc. Alli Liukkonen (University of Jyväskylä) and Dr. Heikki Häkkänen (University of Jyväskylä) for the assistance in laboratory and spectroscopy, respectively. Funding Information: This work was supported by Academy of Finland grants 285461 (H.T.), 330678 (H.T., J.R.), 277194 (H.L.), and 290677 (S.M.). We acknowledge the European Synchrotron Radiation Facility (ESRF) for providing synchrotron access for crystal data collection. We thank Prof. Janne Ihalainen (University of Jyväskylä) for all the help in all aspects of the paper, Prof. Gerrit Groenhof (University of Jyväskylä) for support, and Prof. Nikolai V. Tkachenko (Tampere University) for help and facilities for time-resolved absorption spectroscopy. We also thank M.Sc. Alli Liukkonen (University of Jyväskylä) and Dr. Heikki Häkkänen (University of Jyväskylä) for the assistance in laboratory and spectroscopy, respectively. Publisher Copyright: © 2022, The Author(s). Phytochromes are red light-sensing photoreceptor proteins that bind a bilin chromophore. Here, we investigate the role of a conserved histidine (H260) and tyrosine (Y263) in the chromophore-binding domain (CBD) of Deinococcus radiodurans phytochrome (DrBphP). Using crystallography, we show that in the H260A variant, the missing imidazole side chain leads to increased water content in the binding pocket. On the other hand, Y263F mutation reduces the water occupancy around the chromophore. Together, these changes in water coordination alter the protonation and spectroscopic properties of the biliverdin. These results pinpoint the importance of this conserved histidine and tyrosine, and the related water network, for the function and applications of phytochromes.

Weak complexes of isocyanic acid (HNCO) with nitrogen were studied computationally employing MP2, B2PLYPD3 and B3LYPD3 methods and experimentally by FTIR matrix isolation technique. The results show that HNCO interacts specifically with N2. For the 1:1 stoichiometry, three stable minima were located on the potential energy surface. The most stable of them involves a weak, almost linear hydrogen bond from the NH group of the acid molecule to nitrogen molecule lone pair. Two other structures are bound by van der Waals interactions of N⋯N and C⋯N types. The 1:2 and 2:1 HNCO complexes with nitrogen were computationally tracked as well. Similar types of interactions as in the 1:1 complexes were found in the case of the higher stoichiometry complexes. Analysis of the HNCO/N2/Ar spectra after deposition indicates that the 1:1 hydrogen-bonded complex is prevalent in argon matrices with a small amount of the van der Waals structures also present. Upon annealing, complexes of the 1:2 and 2:1 stoichiometry were detected as well.

POVZETEK 1.8. Uvod Sladkorna bolezen tipa 1 (SB1) je ena najpogostejših kroničnih bolezni otroštva. Slabo urejena sladkorna bolezen vpliva na delovanje možganov. Z raziskavami so ugotovili, da imajo bolniki s SB1 in SB2 med akutno hiperglikemijo nižje dosežke pri govornem in celostnem IQ preizkusu. Vzrok kognitivnega upada pri bolnikih s SB1 ni znan, predpostavlja se, da bi bil lahko povezan z oksidativnim stresom in vnetjem. Prav tako še ni znano, katera področja možganov so najbolj prizadeta. 1.9. Cilji Cilji raziskave so bili: ? s fMRI opredeliti vpliv akutne hiperglikemije (20 mmol/l) na področja možganov, povezanih z načrtovanjem, prostorskim spominom in impulzivnostjo pri otrocih in mladostnikih s SBT1 ? z 1 H-MRS opredeliti vpliv 2-urne hiperglikemije na koncentracijo glukoze, mioinozitola, N- acetilaspartata, holina v področjih možganov, ki so vključene pri nadzornih funkcijah (talamus, frontalna možganska skorja, frontalna bela možganovina) pri otrocih in mladostnikih s SBT1. ? opredeliti vpliv 2-urne hiperglikemije na raven vnetnih mediatorjev (IL-6, fibrinogen) v periferni krvi pri otrocih in mladostnikih s SBT1 1.10. Metode V raziskavi je sodelovalo 20 otrok s SB1, starih med 11 in 19 let, brez kliničnih zapletov SB1, s podobno urejenostjo SB 1 v zadnjih 3 letih (HbA1c), normalno prehranjenih (ITM), nekadilcev, zdravljenih z intenzivirano inzulinsko shemo ali z inzulinsko črpalko, brez diabetične ketoacidoze ali težke hipoglikemije v zadnjem letu, s trajanjem SB1 5-10 let ter 20 zdravih prostovoljcev, skladnih po starosti. Otroci s SB1 so med evglikemično in hiperglikemično zanko opravili tako fMRI (Flankerjeva naloga, Londonski stolp, kapaciteta delovnega spomina) kot tudi H 1 -MRS preiskave. Vse MR preiskave so bile opravljene na 3T tomografu. Otrokom s SB1 smo na tešče in po 120-minutni hiperglikemiji odvzeli periferno kri za določitev kazalcev vnetja (IL-6,fibrinogen). Zdravi prostovoljci opravili enake preiskave fMRI in H 1 -MRS kot otroci s SB1, dvakrat zapored v istem dnevu, brez vpliva na vrednost krvnega sladkorja. 1.11. Hipoteze Pričakovali smo, da bomo opredelili: ? povečano delovanje možgan med izvajanjem naloge načrtovanja (Londonski stolp) med kratkotrajno hiperglikemijo v primerjavi z evglikemijo ? povečano delovanje možgan med izvajanjem naloge prostorskega spomina med kratkotrajno hiperglikemijo v primerjavi z evglikemijo ? večjo impulzivnost med kratkotrajno hiperglikemijo v primerjavi z evglikemijo ? spremembo koncentracije nevrotransmiterjev v določenih področjih možgan, povezanih z nadzornimi funkcijami, kar bi kazalo na spremembe v prenosu signala, ter funkciji celičnih membrane med kratkotrajno hiperglikemijo v primerjavi z evglikemijo povečanje koncentracije kazalcev vnetja v periferni krvi po kratkotrajni hiperglikemiji 1.12. Pomembnost Zaenkrat še ni objave fMRI med akutno hiperglikemijo, z izjemo abstrakta predstavljanega na ADA srečanju leta 2015, ko so pokazali, da je med akutno hiperglikemijo v stanju mirovanja povišana aktivacija možgan (fMRI resting state), zato bodo rezultati naše raziskave povsem izvirni. Ocena možnih škodljivih vplivov akutne hiperglikemije na kognicijo je pomembna za nadaljnje smernice zdravljenja sladkorne bolezni tipa 1, v smislu intenzivnosti inzulinske terapije in ciljev glede urejenosti. 1.13. Rezultati Med nalogo prostorskega spomina smo zaznali zmanjšano zmogljivost prostorskega delovnega spomina med akutno hiperglikemijo in pomembne razlike v aktivaciji regij zanimanja v različnih fazah prostorskega delovnega spomina (p = 0,014). Prostornina sive možganovine (p

International audience; The $\beta$ decay of the neutron-rich $^{134}$In and $^{135}$In was investigated experimentally in order to provide new insights into the nuclear structure of the tin isotopes with magic proton number $Z=50$ above the $N=82$ shell. The $\beta$-delayed $\gamma$-ray spectroscopy measurement was performed at the ISOLDE facility at CERN, where indium isotopes were selectively laser-ionized and on-line mass separated. Three $\beta$-decay branches of $^{134}$In were established, two of which were observed for the first time. Population of neutron-unbound states decaying via $\gamma$ rays was identified in the two daughter nuclei of $^{134}$In, $^{134}$Sn and $^{133}$Sn, at excitation energies exceeding the neutron separation energy by 1 MeV. The $\beta$-delayed one- and two-neutron emission branching ratios of $^{134}$In were determined and compared with theoretical calculations. The $\beta$-delayed one-neutron decay was observed to be dominant $\beta$-decay branch of $^{134}$In even though the Gamow-Teller resonance is located substantially above the two-neutron separation energy of $^{134}$Sn. Transitions following the $\beta$ decay of $^{135}$In are reported for the first time, including $\gamma$ rays tentatively attributed to $^{135}$Sn. In total, six new levels were identified in $^{134}$Sn on the basis of the $\beta \gamma \gamma$ coincidences observed in the $^{134}$In and $^{135}$In $\beta$ decays. A transition that might be a candidate for deexciting the missing neutron single-particle $13/2^+$ state in $^{133}$Sn was observed in both $\beta$ decays and its assignment is discussed. Experimental level schemes of $^{134}$Sn and $^{135}$Sn are compared with shell-model predictions. Using the fast timing technique, half-lives of the $2^+$, $4^+$ and $6^+$ levels in $^{134}$Sn were determined.

Only scarce information is available about the abundance of microplastics (MPs) in Nordic lakes. In this study, the occurrence, types, and distribution of MPs were assessed based on the lake water and sediment samples collected from a sub-basin of Lake Saimaa, Finland. The main goal was to estimate the possible effect of the local wastewater treatment plant (WWTP) on the abundance of MPs in different compartments of the recipient lake area. Collected bottom sediment samples were Cs-137 dated and the chronological structure was utilized to relate the concentrations of MPs to their sedimentation years. Raman microspectroscopy was used for the MPs’ identification from both sample matrices. In addition, MPs consisting of polyethylene (PE), polypropylene (PP) and polystyrene (PS) were quantified from lake water samples by pyrolysis-gas chromatography-mass spectrometry to provide a complementary assessment of MPs based on two different analysis methods, which provide different metrics of the abundance of microplastics. MPs concentrations were highest in sediment samples closest to the discharge site of WWTP effluents (4400 ± 620 n/kg dw) compared to other sites. However, such a trend was not found in lake water samples (0.7 ± 0.1 n/L). Overall, microplastic fibers were relatively more abundant in sediment (70%) than in water (40%), and the majority of detected microplastic fibers were identified as polyester. This indicates that a part of textile fibers passing the WWTP processes accumulate in the sediment close to the discharge site. In addition, the abundance of MPs was revealed to have increased slightly during the last 30 years. Highlights • Higher concentrations of microplastics were detected in sediments closer to WWTP. • Polyester fibers were the most common type of plastics near WWTP. • Microplastic pollution has slightly increased from 1990 to 2018.

FTIR spectroscopy was combined with the matrix isolation technique and quantum chemical calculations with the aim of studying complexes of isocyanic acid with sulfur dioxide. The structures of the HNCO⋯SO2 complexes of 1:1, 1:2 and 2:1 stoichiometry were optimized at the MP2, B3LYPD3, B2PLYPD3 levels of theory with the 6-311++G(3df,3pd) basis set. Five stable 1:1 HNCO⋯SO2 complexes were found. Three of them contain a weak N-H⋯O hydrogen bond, whereas two other structures are stabilized by van der Waals interactions. The analysis of the HNCO/SO2/Ar spectra after deposition indicates that mostly the 1:1 hydrogen-bonded complexes are present in argon matrices, with a small amount of the van der Waals structures. Upon annealing, complexes of the 1:2 stoichiometry were detected, as well.

Collinear laser spectroscopy of the N=Z=21 self-conjugate nucleus 42Sc has been performed at the JYFL IGISOL IV facility in order to determine the change in nuclear mean-square charge radius between the Iπ=0+ ground state and the Iπ=7+ isomer via the measurement of the 42g,42mSc isomer shift. New multi-configurational Dirac-Fock calculations for the atomic mass shift and field shift factors have enabled a recalibration of the charge radii of the 42−46Sc isotopes which were measured previously. While consistent with the treatment of proton-neutron, proton-proton and neutron-neutron pairing on an equal footing, the reduction in size for the isomer is observed to be of a significantly larger magnitude than that expected from both shell-model and ab-initio calculations. The measured nuclear magnetic dipole moment and electric quadruple moment, on the other hand, are in good agreement with simple empirical estimates and shell-model calculations. Collinear laser spectroscopy of the $N=Z=21$ self-conjugate nucleus $^{42}$Sc has been performed at the JYFL IGISOL IV facility in order to determine the change in nuclear mean-square charge radius between the $I^{\pi}=0^{+}$ ground state and the $I^{\pi}=7^{+}$ isomer via the measurement of the $^{42\mathrm{g},42\mathrm{m}}$Sc isomer shift. New multi-configurational Dirac-Fock calculations for the atomic mass shift and field shift factors have enabled a recalibration of the charge radii of the $^{42-46}$Sc isotopes which were measured previously. While consistent with the treatment of proton-neutron, proton-proton and neutron-neutron pairing on an equal footing, the reduction in size for the isomer is observed to be of a significantly larger magnitude than that expected from both shell model and ab-initio calculations.

Aerosol particles play significant roles in atmospheric processes but their effects pose large uncertainties in climate predictions. This thesis presents computational and experimental studies of aqueous organic and organic-inorganic solutions that serve as model systems of cloud droplets for better understanding of aerosols and their impact on climate. Carbon and oxygen K-edge X-ray Absorption Spectroscopy (XAS) has been applied in order to study molecular level interactions in aqueous solutions of glyoxal and methylglyoxal and to investigate potential salting effects with addition of inorganic salts to the solutions. The spectra were used for identification of chemical bonds and hydrated forms in the solutions. Carbon K-edge XAS was applied also for the study of binary aqueous solutions comprising surfactantssodium hexanoate and sodium octanoate. The solutions were measured for concentrations of solutes above and below the critical micelle concentration in order to observe the formation of micelles in the solution. In the case of aqueous sodium octanoate changes in the shapes of the spectra with increasing concentrations suggest changes in the chemical environment of the carbon atoms that could possibly be related to micelle formation. COSMOtherm, a software based on COSMO-RS (COnductor like Screening MOdel for Real Solvents), was used to predict solubilities and activity coefficients for C₂–C₁₂ fatty acids with even number of carbon atoms and their sodium salts in binary aqueous solutions and also in ternary solutions, comprising inorganic salts. The computed values indicate that COSMOtherm can be used to provide information about atmospheric organic components of aqueous solutions where experimental data are currently inaccessible. The results of these studies contribute to understanding of cloud microphysics and may be used to improve accuracy of atmospheric model predictions. Abstrakti Aerosolihiukkasilla on merkittävä rooli ilmakehän prosesseissa, mutta niiden vaikutuksiin liittyy suuria epävarmuuksia ilmastoennusteissa. Tässä tutkielmassa on tehty laskennallisia ja kokeellisia tutkimuksia orgaanisten aineiden vesiliuoksista sekä epäorgaanisten suolojen kanssa että ilman niitä. Nämä vesiliuokset ovat mallisysteemejä pilvipisaroille, ja niiden tutkimus auttaa ymmärtämään paremmin aerosoleja ja niiden ilmastovaikutuksista. Hiilen ja hapen K-kuoren röntgenabsorptiospektroskopialla tutkittiin molekyylitason vuorovaikutuksia glyoksaalin ja metyyliglyoksaalin vesiliuoksissa ja näiden orgaanisten aineiden aiheuttamia mahdollisia muutoksia epäorgaanisten suolojen liukoisuuteen. Röntgenabsorptiospektrejä käytettiin kemiallisten sidosten ja hydratoituneiden muotojen tunnistamiseen. Hiilen K-kuoren röntgenabsorptiospektroskopiaa sovellettiin myös pinta-aktiivisia aineita (natriumheksanoaattia ja -oktanoaattia) sisältävien vesiliuosten tutkimiseen. Mittauksia tehtiin pinta-aktiivisten aineiden pitoisuuksille molemmin puolin ns. kriittistä misellikonsentraatiota, jossa misellien muodostumisen tulisi alkaa; natriumoktanoaatin vesiliuoksen tapauksessa spektrien muoto muuttui pitoisuuden kasvaessa, mikä kertoo hiiliatomien kemiallisen ympäristön muutoksesta mahdolliseen misellien muodostumiseen liittyen. COSMOtherm on COSMO-RS-menetelmään (COnductor like Screening MOdel for Real Solvents) perustuva mallinnusohjelma, jota käytettiin ennustamaan parillisen määrän hiiliatomeja sisältävien C₂–C₁₂ rasvahappojen ja niiden natriumsuolojen liukoisuuksia ja aktiivisuusvakioita vesiliuoksissa ja epäorgaanisia suoloja sisältävissä vesiliuoksissa. Laskennalliset tulokset osoittivat, että COSMOtherm voi antaa arvokasta tietoa ilmakehässä esiintyvien orgaanisten aineiden vesiliuoksista, erityisesti tapauksissa, joissa kokeellisia arvoja ei ole vielä saatavilla. Tutkimusten tulokset auttavat ymmärtämään pilvien mikrofysiikkaa ja niitä voidaan käyttää ilmakehämallien ennusteiden tarkentamisessa.

The abundance of microplastics (MPs) in the atmosphere, on land, and especially in water bodies is well acknowledged. In this study, we establish an optical method based on three different techniques, namely, specular reflection to probe the medium, transmission spectroscopy measurements for the detection and identification, and a speckle pattern for monitoring the sedimentation of MPs filtrated from wastewater sludge and suspended in ethanol. We used first Raman measurements to estimate the presence and types of different MPs in wastewater sludge samples. We also used microscopy to identify the shapes of the main MPs. This allowed us to create a teaching set of samples to be characterized with our optical method. With the developed method, we clearly show that MPs from common plastics, such as polypropylene (PP), polyethylene terephthalate (PET), polystyrene (PS), and polyethylene (PE), are present in wastewater sludge and can be identified. Additionally, the results also indicate that the density of the plastics, which influences the sedimentation, is an essential parameter to consider in optical detection of microplastics in complex natural environments. All of the methods are in good agreement, thus validating the optics-based solution. peerReviewed

The photochemistry of matrix-isolated glycolic acid, induced by UV light, was studied by FTIR spectroscopy and B3LYPD3/6-311++G(3df,3pd) calculations. Several decomposition pathways were found to take place upon 212 nm and 226 nm wavelengths irradiation. A number of complexes formed between photoproducts were identified, among them those of formaldehyde with water, carbon monoxide and carbon dioxide as well as the H2O-CO complexes. The structure and spectroscopic assignment of the photoproducts were made comparing the experimental results with the theoretical predictions and available literature data. The observed formation of different complexes indicates various pathways for their formation resulting from UV-induced photodecomposition of different precursor isomers. peerReviewed

Laser-induced time-resolved luminescence was used to study rare earth element (REE) containing natural apatite and calcite minerals. The luminescence from 400 nm to 700 nm in the minerals was analyzed with excitation ranges 210–340 nm and 405–535 nm. As an outcome, several useful excitation wavelengths to detect one or more REE from apatite and calcite are reported. The feasibility of selected excitations in e.g. avoiding the disturbance of intense Mn2+ luminescence band, results was demonstrated with a non-gated detector. peerReviewed

An approach for controlled protein immobilization on laser-induced two-photon (2P) oxidation patterned graphene oxide (GO) surfaces is described. Selected proteins, horseradish peroxidase (HRP) and biotinylated bovine serum albumin (b-BSA) were successfully immobilized on oxidized graphene surfaces, via non-covalent interactions, by immersion of graphene-coated microchips in the protein solution. The effects of laser pulse energy, irradiation time, protein concentration and duration of incubation on the topography of immobilized proteins and consequent defects upon the lattice of graphene were systemically studied by atomic force microscopy (AFM) and Raman spectroscopy. AFM and fluorescence microscopy confirmed the selective aggregation of protein molecules towards the irradiated areas. In addition, the attachment of b-BSA was detected by a reaction with fluorescently labelled avidin-fluorescein isothiocyanate (Av-FITC). In contrast to chemically oxidized graphene, laser-induced oxidation introduces the capability for localization on oxidized areas and tunability of the levels of oxidation, resulting in controlled guidance of proteins by light over graphene surfaces and progressing towards graphene microchips suitable for biomedical applications. peerReviewed

Mapping with laser-induced breakdown spectroscopy (LIBS) can offer more than just the spatial distribution of elements: the rich spectral information also enables mineral recognition. In the present study, statistical approaches were used for the recognition of the spodumene from lithium pegmatite ores. A broad spectral range (280–820 nm) with multiple lines was first used to establish the methods based on vertex component analysis (VCA) and K-means and DBSCAN clusterings. However, with a view to potential on-site applications, the dimensions of the datasets must be reduced in order to accomplish fast analysis. Therefore, the capability of the methods in mineral identification was tested with a limited spectral range (560–815 nm) using Li-pegmatites with various mineralogical characters. peerReviewed

The mean lifetimes of the lowest energy 2+, 8+ and 9− states in 166Os have been measured using the recoil distance Doppler-shift method in conjunction with a selective recoil-decay tagging technique. These measurements extend studies into the most neutron-deficient mass region accessible to current experimental methods. The B(E2; 2+ → 0+) = 7(2) W.u. extracted from these measurements is markedly lower than those observed in the heavier even-mass Os isotopes. The 8+ and 9− states yield reduced transition probabilities that are consistent with single-particle transitions. While these values may indicate a departure from collective structure, the level scheme and the underlying nuclear configurations can also be interpreted in terms of a simple collective picture. This contrasting behaviour suggests an intriguing dichotomy in the description of heavy transitional nuclei. peerReviewed

openaire: EC/H2020/838996/EU//RealNanoPlasmon Electronic circular dichroism (ECD) is a powerful spectroscopy method for investigating chiral properties at the molecular level. ECD calculations with the commonly used linear-response time-dependent density functional theory (LR-TDDFT) framework can be prohibitively costly for large systems. To alleviate this problem, we present here an ECD implementation within the projector augmented-wave method in a real-time-propagation TDDFT framework in the open-source GPAW code. Our implementation supports both local atomic basis sets and real-space finite-difference representations of wave functions. We benchmark our implementation against an existing LR-TDDFT implementation in GPAW for small chiral molecules. We then demonstrate the efficiency of our local atomic basis set implementation for a large hybrid nanocluster and discuss the chiroptical properties of the cluster.

This paper presents high-precision spectroscopic measurements of atomic tin using five different resonance-ionization schemes performed with the collinear resonance-ionization spectroscopy technique. Isotope shifts were measured for the stable tin isotopes from the $5{s}^{2}5{p}^{2}\phantom{\rule{0.28em}{0ex}}^{3}{P}_{0,1,2}$ and ${}^{1}{S}_{0}$ to the $5{s}^{2}5p6s\phantom{\rule{0.28em}{0ex}}^{1}{P}_{1},^{3}{P}_{1,2}$ and $5{s}^{2}5p7s{\phantom{\rule{0.28em}{0ex}}}^{1}{P}_{1}$ atomic levels. The magnetic dipole hyperfine constants ${A}_{\mathrm{hf}}$ have been extracted for six atomic levels with electron angular momentum $Jg0$ from the hyperfine structures of nuclear spin $I=1/2$ tin isotopes, $^{115,117,119}\mathrm{Sn}$. State-of-the-art atomic calculations using a relativistic Fock-space coupled-cluster method and the configuration interaction approach combined with many-body perturbation theory allow accurate and reliable calculations of both field- and mass-shift factors for the studied transitions, in addition to the hyperfine magnetic fields and electric-field gradients of the atomic levels. The excellent agreement with the experimental results highlights the accuracy of modern atomic theory and establishes an important foundation for precision measurements of nuclear moments and charge radii of the most exotic isotopes of tin.

Physical review / C 103(1), 014318 (2021). doi:10.1103/PhysRevC.103.014318, Published by Inst., Woodbury, NY

Molecular spectroscopy offers opportunities for the exploration of the fundamental laws of nature and the search for new particle physics beyond the standard model1–4. Radioactive molecules—in which one or more of the atoms possesses a radioactive nucleus—can contain heavy and deformed nuclei, offering high sensitivity for investigating parity- and time-reversal-violation effects5,6. Radium monofluoride, RaF, is of particular interest because it is predicted to have an electronic structure appropriate for laser cooling6, thus paving the way for its use in high-precision spectroscopic studies. Furthermore, the effects of symmetry-violating nuclear moments are strongly enhanced5,7–9 in molecules containing octupole-deformed radium isotopes10,11. However, the study of RaF has been impeded by the lack of stable isotopes of radium. Here we present an experimental approach to studying short-lived radioactive molecules, which allows us to measure molecules with lifetimes of just tens of milliseconds. Energetically low-lying electronic states were measured for different isotopically pure RaF molecules using collinear resonance ionisation at the ISOLDE ion-beam facility at CERN. Our results provide evidence of the existence of a suitable laser-cooling scheme for these molecules and represent a key step towards high-precision studies in these systems. Our findings will enable further studies of short-lived radioactive molecules for fundamental physics research., Measurements of low-energy electronic states of radium monofluoride validate predictions of the use of this short-lived radioactive molecule in exploring fundamental physics and provide evidence of its suitability for laser cooling.

Realization of Fano resonance in plasmonic oligomers is often exploited to design efficient plasmonic substrates for surface-enhanced coherent anti-Stokes Raman scattering. Disk-type Fano-resonant plasmonic oligomers are widely used to enhance the Raman signal of the probe material. Generally, hot spots are generated in those oligomers at different spatial locations at different wavelengths and only a few spatially overlapping hot spots at multiple wavelengths can be achieved with oblique incidence of excitation light. In this work, we proposed hexagonal gold nanoparticle based Fano-resonant plasmonic oligomers that can yield higher number of spatially overlapped hot spots compared to the disk type oligomers even with the normal incidence of excitation light. The oligomers were numerically modelled and optimized for surface-enhanced coherent anti-Stokes Raman scattering with 780 nm pumping and 500–1800 cm− 1 Raman signature region. The Fano lineshape was engineered to ensure near-field energy coupling at pump while enhancing the coherent anti-Stokes Raman signal at the far field. Our computational studies explored the purely electric origin of Fano resonance in those oligomers and provided maximum Raman enhancements of 1012–1013 from them to enable single-molecular level applications. Our findings provide a way to realize fabrication-friendly nanostructures with higher number of spatially localized hotspots for improving the Raman detection sensitivity.