| 1. |
- Gad, Helge, et al.
(författare)
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MTH1 inhibition eradicates cancer by preventing sanitation of the dNTP pool
- 2014
-
Ingår i: Nature. - : Nature Publishing Group. - 0028-0836 .- 1476-4687. ; 508:7495, s. 215-221
-
Tidskriftsartikel (refereegranskat)abstract
- Cancers have dysfunctional redox regulation resulting in reactive oxygen species production, damaging both DNA and free dNTPs. The MTH1 protein sanitizes oxidized dNTP pools to prevent incorporation of damaged bases during DNA replication. Although MTH1 is non-essential in normal cells, we show that cancer cells require MTH1 activity to avoid incorporation of oxidized dNTPs, resulting in DNA damage and cell death. We validate MTH1 as an anticancer target in vivo and describe small molecules TH287 and TH588 as first-in-class nudix hydrolase family inhibitors that potently and selectively engage and inhibit the MTH1 protein in cells. Protein co-crystal structures demonstrate that the inhibitors bindin the active site of MTH1. The inhibitors cause incorporation of oxidized dNTPs in cancer cells, leading to DNA damage, cytotoxicity and therapeutic responses in patient-derived mouse xenografts. This study exemplifies the non-oncogene addiction concept for anticancer treatment and validates MTH1 as being cancer phenotypic lethal.
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| 2. |
- Tchaplyguine, Maxim, et al.
(författare)
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Absolute core-level binding energy shifts between atom and solid: The Born-Haber cycle revisited for free nanoscale metal clusters
- 2008
-
Ingår i: Journal of Electron Spectroscopy and Related Phenomena. - : Elsevier BV. - 0368-2048 .- 1873-2526. ; 166, s. 38-44
-
Tidskriftsartikel (refereegranskat)abstract
- Core-level binding energy shifts between the free atom and corresponding large clusters, the latter closely approximating the infinite solid, have been experimentally derived for several elemental metals. The cluster core-level binding energies in question have been determined relative to the vacuum level using synchrotron-based photoelectron spectroscopy. As expected, the experimental shift values show reasonable agreement with those calculated using the thermochemical Born–Haber cycle approach. The largest uncertainty factors defining the discrepancies between the experiment and the model, such as the difference in the multiplet structure of free atoms and the solid, the in some cases indirectly established cluster work functions, and the metal solvation energy, are discussed.
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| 3. |
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| 4. |
- Abarenkov, Kessy, et al.
(författare)
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Annotating public fungal ITS sequences from the built environment according to the MIxS-Built Environment standard – a report from a May 23-24, 2016 workshop (Gothenburg, Sweden)
- 2016
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Ingår i: MycoKeys. - : Pensoft Publishers. - 1314-4057 .- 1314-4049. ; 16, s. 1-15
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Tidskriftsartikel (refereegranskat)abstract
- Recent molecular studies have identified substantial fungal diversity in indoor environments. Fungi and fungal particles have been linked to a range of potentially unwanted effects in the built environment, including asthma, decay of building materials, and food spoilage. The study of the built mycobiome is hampered by a number of constraints, one of which is the poor state of the metadata annotation of fungal DNA sequences from the built environment in public databases. In order to enable precise interrogation of such data – for example, “retrieve all fungal sequences recovered from bathrooms” – a workshop was organized at the University of Gothenburg (May 23-24, 2016) to annotate public fungal barcode (ITS) sequences according to the MIxS-Built Environment annotation standard (http://gensc.org/mixs/). The 36 participants assembled a total of 45,488 data points from the published literature, including the addition of 8,430 instances of countries of collection from a total of 83 countries, 5,801 instances of building types, and 3,876 instances of surface-air contaminants. The results were implemented in the UNITE database for molecular identification of fungi (http://unite.ut.ee) and were shared with other online resources. Data obtained from human/animal pathogenic fungi will furthermore be verified on culture based metadata for subsequent inclusion in the ISHAM-ITS database (http://its.mycologylab.org).
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| 5. |
- Adolphi, Florian, et al.
(författare)
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Persistent link between solar activity and Greenland climate during the Last Glacial Maximum
- 2014
-
Ingår i: Nature Geoscience. - 1752-0908 .- 1752-0894. ; 7:9, s. 662-666
-
Tidskriftsartikel (refereegranskat)abstract
- Changes in solar activity have previously been proposed to cause decadal- to millennial-scale fluctuations in both the modern and Holocene climates(1). Direct observational records of solar activity, such as sunspot numbers, exist for only the past few hundred years, so solar variability for earlier periods is typically reconstructed from measurements of cosmogenic radionuclides such as Be-10 and C-14 from ice cores and tree rings(2,3). Here we present a high-resolution Be-10 record from the ice core collected from central Greenland by the Greenland Ice Core Project (GRIP). The record spans from 22,500 to 10,000 years ago, and is based on new and compiled data(4-6). Using C-14 records(7,8) to control for climate-related influences on Be-10 deposition, we reconstruct centennial changes in solar activity. We find that during the Last Glacial Maximum, solar minima correlate with more negative delta O-18 values of ice and are accompanied by increased snow accumulation and sea-salt input over central Greenland. We suggest that solar minima could have induced changes in the stratosphere that favour the development of high-pressure blocking systems located to the south of Greenland, as has been found in observations and model simulations for recent climate(9,10). We conclude that the mechanism behind solar forcing of regional climate change may have been similar under both modern and Last Glacial Maximum climate conditions.
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| 6. |
- Ahmed, Aisha S, et al.
(författare)
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NF-κB-Associated Pain-Related Neuropeptide Expression in Patients with Degenerative Disc Disease.
- 2019
-
Ingår i: International Journal of Molecular Sciences. - : MDPI AG. - 1661-6596 .- 1422-0067. ; 20:3
-
Tidskriftsartikel (refereegranskat)abstract
- The role of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) has been highlighted in mechanisms underlying inflammatory and neuropathic pain processes. The present study was designed to investigate whether NF-κB signaling is associated with pain-related neuropeptide expression in patients with chronic back pain related to degenerative disc disease (DDD). Intervertebral disc (IVD) tissues were collected from forty DDD patients undergoing disc replacement or fusion surgery, and from eighteen postmortem (PM) control subjects. RELA, NFKB1, CGRP, TAC1, TRPV1, and MMP-3 gene expression were analyzed by RT-qPCR, while NF-κB subunit RelA and NF-κB1⁻DNA binding in nuclear extracts and calcitonin gene related peptide (CGRP), substance P (SP), and transient receptor potential, subfamily V, member 1 (TRPV1) protein levels in cytosolic extracts of tissues were assessed by enzyme-linked immunosorbent assay (ELISA). An upregulated NF-κB1⁻DNA binding, and higher CGRP and TRPV1 protein levels were observed in DDD patients compared to PM controls. In DDD patients, NF-κB1⁻DNA binding was positively correlated with nuclear RelA levels. Moreover, NF-κB1⁻DNA binding was positively associated with TRPV1 and MMP-3 gene and SP and TRPV1 protein expression in DDD patients. Our results indicate that the expression of SP and TRPV1 in IVD tissues was associated with NF-κB activation. Moreover, NF-κB may be involved in the generation or maintenance of peripheral pain mechanisms by the regulation of pain-related neuropeptide expression in DDD patients.
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| 7. |
- Andersson, Svante, 1962-, et al.
(författare)
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A Glocal marketing model
- 2009. - 1
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Ingår i: Glocal Marketing. - Lund. - 9789144055558 ; , s. 391-396
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Bokkapitel (refereegranskat)
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| 8. |
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| 9. |
- Andersson, Svante, 1962-, et al.
(författare)
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Early Internationalizing Firms
- 2009. - 1
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Ingår i: Glocal marketing. - Lund. - 9789144055558 ; , s. 45-64
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Bokkapitel (refereegranskat)
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| 10. |
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| 11. |
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| 12. |
- Andersson, Svante, 1962-, et al.
(författare)
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Mega-sport football events’ influence on destination images : A study of the 2016 UEFA European Football Championship in France, the 2018 FIFA World Cup in Russia, and the 2022 FIFA World Cup in Qatar
- 2021
-
Ingår i: Journal of Destination Marketing & Management. - Amsterdam : Elsevier. - 2212-571X .- 2212-5752. ; 19
-
Tidskriftsartikel (refereegranskat)abstract
- The purpose of this study is to examine whether mega-sport events influence visitors' destination images and to explore which factors influence their perceptions of and intentions to attend a mega-sport event in certain destinations. We examine visitors' perceptions of the 2016 UEFA European Football Championship in France, the 2018 FIFA World Cup in Russia, and the upcoming 2022 FIFA World Cup in Qatar through a structured questionnaire published on the Facebook group Camp Sweden, a community of Swedish football supporters. We find differences among supporters’ destination image after they attended the mega-sport football events. The study also shows that positive destination images after visits were based on whether the destinations were able to satisfy important factors for supporters when visiting the destination. Qatar will be challenged to improve its destination image, as supporters do not connect factors important for visiting destinations with their current perceptions of Qatar. © 2020 Elsevier Ltd
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| 13. |
- Andersson, Svante, 1962-, et al.
(författare)
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Sustainable development considerations in supply chains : Firms' relationships with stakeholders in their business sustainability practices—A triangular comparison
- 2022
-
Ingår i: Business Strategy and the Environment. - Oxford : John Wiley & Sons. - 0964-4733 .- 1099-0836. ; 32:4, s. 1885-1899
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Tidskriftsartikel (refereegranskat)abstract
- This study aims to investigate focal firms' business sustainability relationships in connection with their stakeholders in supply chain networks. A questionnaire survey was sent to a sample consisting of large Swedish firms, with 107 usable questionnaires returned. The results reveal which stakeholders are of interest for firms in sustainability efforts. The results are compared with earlier findings from Norway and Spain in a triangular approach. The former is a similar country, while the latter is different to Sweden in several ways. In addition, the study uncovers which stakeholders in the supply chain network should be considered. The study also demonstrates how firms can implement business sustainability in their supply chain networks and shows the extent to which different stakeholders are considered in sustainability efforts. The study contributes to sustainability research and stakeholder theory in supply chain networks. Opposite to earlier findings, this study showed only minor influences from national culture and institutions on firms' sustainable business practices in supply chain networks. © 2022 The Authors. Business Strategy and The Environment published by ERP Environment and John Wiley & Sons Ltd.
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| 14. |
- Andersson, Svante, 1962-, et al.
(författare)
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Sustainable development—Direct and indirect effects between economic, social, and environmental dimensions in business practices
- 2022
-
Ingår i: Corporate Social Responsibility and Environmental Management. - Oxford : John Wiley & Sons. - 1535-3958 .- 1535-3966. ; 29:5, s. 1158-1172
-
Tidskriftsartikel (refereegranskat)abstract
- This study investigates the direct and indirect effects between economic, social and environmental dimensions of triple bottom line (TBL), based on a questionnaire survey and cross-industrial sample in Sweden. The analyses apply partial least squares structural equation models. The study tests the direct and indirect effects between economic, social, and environmental dimensions of TBL and offers additional validity and reliability to establish the measurement and structural properties between the dimensions of TBL. The study extends earlier findings by explicitly discussing how the three TBL goals relate to each other and shows how the dynamic capability view can be a fruitful lens to investigate business sustainability. Some differences in sustainability business practices caused by differences in national cultures are identified. Sustainability reporting in a strong uncertainty avoidance (UA) country happens in accordance with regulations and laws. Conversely, for weak UA cultures, reporting and compliance with regulations are ways to build trust with stakeholders. That is, reporting is more transparent and widespread in weak UA countries. The study also provides a foundation to guide companies' actions of business sustainability. The model shows companies how to establish the order of actions undertaken across economic, social, and environmental dimensions. In addition, it clarifies that the economic dimension exerts an effect on the social and environmental dimensions. The model also grasps long-term economic performance by including competitiveness and brand value, while earlier research mainly has focused on more short-term measurements as return on assets. © 2022 The Authors. Corporate Social Responsibility and Environmental Management published by ERP Environment and John Wiley & Sons Ltd.
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| 15. |
- Andersson, Svante, 1962-, et al.
(författare)
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The International Entrepreneur
- 2009. - 1
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Ingår i: Glocal Marketing. - Lund : Studentlitteratur. - 9789144055558 ; , s. 257-276
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Bokkapitel (refereegranskat)
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| 16. |
- Andersson, Svante, 1962-, et al.
(författare)
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Think Globally and Act Locally
- 2009. - 1
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Ingår i: Glocal Marketing. - Lund : Studentlitteratur. - 9789144055558 ; , s. 13-26
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Bokkapitel (refereegranskat)
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| 17. |
- Andersson, Tomas, et al.
(författare)
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Photon energy influence on valence photoelectron spectra of silver clusters
- 2012
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Ingår i: Journal of Physics, Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 388:15, s. 152028-
-
Tidskriftsartikel (refereegranskat)abstract
- Silver clusters in the size range of ∼102 constituent atoms have been studied using photoelectron spec-troscopy. The 5s and 4d valence bands have been probed with 40 and 60.5 eV photon energies. Differences in the valence band spectral features have been observed and are discussed in view of earlier results on copper clusters and in terms of differences in mean free path for electrons of different energies.
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| 18. |
- Andersson, Tomas, et al.
(författare)
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Plasmon single- and multi-quantum excitation in free metal clusters as seen by photoelectron spectroscopy
- 2011
-
Ingår i: Journal of Chemical Physics. - : AIP Publishing. - 0021-9606 .- 1089-7690. ; 134:9, s. 094511-
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Tidskriftsartikel (refereegranskat)abstract
- Plasmons are investigated in free nanoscale Na, Mg, and K metal clusters using synchrotron radiation-based x-ray photoelectron spectroscopy. The core levels for which the response from bulk and surface atoms can be resolved are probed over an extended binding energy range to include the plasmon loss features. In all species the features due to fundamental plasmons are identified, and in Na and K also those due to either the first order plasmon overtones or sequential plasmon excitation are observed. These features are discussed in view of earlier results for planar macroscopic samples and free clusters of the same materials.
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| 19. |
- Andersson, Tomas, et al.
(författare)
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The electronic structure of free aluminum clusters: Metallicity and plasmons
- 2012
-
Ingår i: Journal of Chemical Physics. - : AIP Publishing. - 0021-9606 .- 1089-7690. ; 136:20
-
Tidskriftsartikel (refereegranskat)abstract
- The electronic structure of free aluminum clusters with similar to 3-4 nm radius has been investigated using synchrotron radiation-based photoelectron and Auger electron spectroscopy. A beam of free clusters has been produced using a gas-aggregation source. The 2p core level and the valence band have been probed. Photoelectron energy-loss features corresponding to both bulk and surface plasmon excitation following photoionization of the 2p level have been observed, and the excitation energies have been derived. In contrast to some expectations, the loss features have been detected at energies very close to those of the macroscopic solid. The results are discussed from the point of view of metallic properties in nanoparticles with a finite number of constituent atoms. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4718362]
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| 20. |
- Arion, Tiberiu, et al.
(författare)
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New insight into the Auger decay process in O-2: The coincidence perspective
- 2012
-
Ingår i: Journal of Electron Spectroscopy and Related Phenomena. - : Elsevier BV. - 0368-2048 .- 1873-2526. ; 185:8-9, s. 234-243
-
Tidskriftsartikel (refereegranskat)abstract
- Photoelectron-Auger electron coincidence spectroscopy is a powerful tool for the investigation of Auger decay processes with different core-ionized intermediate states. In this paper we describe an investigation into the Auger decay of the O-2 molecule, with the purpose of bringing new insight into the dynamics of the core hole decay mechanism. Using a novel experimental approach to measuring such coincidence spectra we report the highest resolution Auger spectrum of O-2 recorded hitherto. In our approach, we have combined the advantages of these coincidence spectra with the high resolution and excellent signal-to-noise ratios of non-coincident Auger spectra and a state-of-the-art fit analysis. In this way we have derived information about the potential energy curves of the final states W-3 Delta(u), B-3 Pi(g), and B' (3)Sigma(-)(u) and concluded that the corresponding Auger transitions are formed to a large part by strongly overlapping vibrational progressions. The present findings are compared to earlier results reported in the literature confirming some theoretical predictions. (C) 2012 Elsevier B.V. All rights reserved.
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| 21. |
- Arup, Ulf, et al.
(författare)
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Lavar Lichenes
- 2015
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Ingår i: Rödlistade arter i Sverige 2015. - 9789187853104 ; , s. 72-79
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 22. |
- Arup, Ulf, et al.
(författare)
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Rödlista över lavar Lichenes
- 2020
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Ingår i: Rödlistade arter i Sverige 2020. - 9789187853548 - 9789187853555 ; , s. 89-96
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 23. |
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| 24. |
- Baev, A, et al.
(författare)
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Picturing molecular femtosecond processes through an ultra-fast controllable X-ray shutter
- 2003
-
Ingår i: Chemical Physics. - 0301-0104 .- 1873-4421. ; 289, s. 51-56
-
Tidskriftsartikel (refereegranskat)abstract
- We show that frequency detuning in a resonant X-ray scattering experiment acts as an X-ray camera shutter by regulating the duration time of the scattering process. The camera shutter can be used to select processes at different time scales for observation. This is illustrated by a resonant Auger study of the ultra-fast dissociation of the core-excited HF molecule. We present experimental results and first principle simulations of the molecular fraction in the resonant Auger spectra of HF which is a dynamical parameter that well illustrates X-ray shutter controlled dissociation.
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| 25. |
- Bao, Zhuo, et al.
(författare)
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Detailed Theoretical and Experimental Description of Normal Auger Decay in O2
- 2008
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Ingår i: Journal of Physics B. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 41:12, s. 125101-
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Tidskriftsartikel (refereegranskat)abstract
- The normal Auger electron spectrum of the O-2 molecule is assigned in detail on the basis of ab initio valence configuration interaction (CI) wavefunctions. Potential energy curves of the ground state, the core-ionized states and the doubly charged final states are calculated and Auger decay rates are obtained with the one-centre approximation. Using the lifetime vibrational interference method, band shapes are obtained for all contributions to the Auger spectrum. The calculated Auger electron spectrum allows us to identify all features observed experimentally. Significant differences to previous assignments are reported. A quantitative simulation of the spectrum is given on the basis of a curve-fitting procedure, in which the energetic positions and intensities of the theoretical bands were optimized. Besides providing a basis for a refined analysis of the spectrum, the fit allows us to assess the accuracy of the calculation. As expected for this level of theory, the absolute accuracy of the valence CI energies is found to be about 0.3 eV. The inherent error of the one-centre transition rates is less than 5% of the most intense transition in the spectrum. The frequently questioned one-centre Auger transition rates are shown to be rather appropriate if applied with reasonable wavefunctions and if the vibrational band structure of the molecular spectrum is properly taken into account.
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| 26. |
- Bao, Zhuo, 1977-
(författare)
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Synchrotron Radiation Studies of Free and Adsorbed Molecules
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis contains two parts. The first part concerns the research work on free molecules using synchrotron-radiation-related techniques. Auger electron spectra of two free open-shell molecules, O2 and NO, were studied experimentally and theoretically. Photoionization experimental technique with tunable synchrotron radiation source was used to induce core-level electron ionization and obtain the KVV normal Auger electron spectra. A quantitative assignment of O2 normal Auger spectrum was obtained by applying ab initio CI calculations and LVI Auger line shape simulations including the bond length dependence of Auger transition rates. The photon energy dependence of normal Auger electron spectra was focused on with photon energies in the vicinities of core-ionization threshold energies. Consequently, the MAPCI (Molecular Auger Post Collision Interaction) theory was developed. Taking the near-threshold O2 normal Auger spectrum as an example, the two extreme cases of MAPCI effect, “atomic-like PCI” and “molecular PCI”, were discovered and discussed. The effect of shape resonance on near-threshold molecular normal Auger spectrum was discussed taking NO near threshold normal Auger spectra as example.The second part deals with research work on the chemisorption of small epoxy organic molecules, ethylene oxide, methyl oxirane, on Si (100) surfaces. Synchrotron radiation related techniques, UPS, XPS and NEXAFS, were applied. Based on the valence photoemission spectra, C 1s and Si 2p XPS spectra, the epoxy ring opening reactions of these molecules in chemisorption process were proved. Further tentative search for the surface-adsorbate CDAD effect was performed, and no evident circular dichroism was confirmed.
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| 27. |
- Bergersen, Henrik, et al.
(författare)
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First observation of vibrations in core-level photoelectron spectra of free neutral molecular clusters
- 2006
-
Ingår i: Chemical Physics Letters. - : Elsevier BV. - 0009-2614 .- 1873-4448. ; 429:1-3, s. 109-113
-
Tidskriftsartikel (refereegranskat)abstract
- Core-level photoelectron spectra of free neutral methane clusters have been recorded. These spectra exhibit well-resolved surface and bulk features as well as vibrational fine structure. The vibrational structure in the cluster signal is well reproduced by a theoretical model that assumes independent contributions from inter- and intramolecular modes. The intramolecular contribution to the vibrational line-shape is taken to be equal to that of the monomer in the gas phase, while the intermolecular part is simplified to line broadening. An estimate of the cluster size has been made on the basis of the observed surface-to-bulk intensity ratio.
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| 28. |
- Bergersen, Henrik, 1978-
(författare)
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Free Neutral Clusters and Liquids Studied by Electron Spectroscopy and Lineshape Modeling
- 2008
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The electronic and geometrical structure of free neutral clusters and liquids have been studied using synchrotron-radiation based photoelectron and Auger electron spectroscopy in combination with lineshape modeling. A novel experimental setup has been developed for studies of liquids, based on the liquid microjet technique. Theoretical lineshapes have been computed using both classical (molecular dynamics) and quantum mechanical (mainly density functional theory) methods.Clusters are finite ensembles of atoms or molecules, ranging in size from a few to several thousand atoms. Apart from being fundamentally interesting, clusters are also promising as building blocks for nano-technology. In this thesis results are presented for rare-gas and molecular clusters, ranging from weakly van-deer-Waals bonded to hydrogen bonded. It is shown that the combination of core-level photoelectron spectroscopy (XPS) and lineshape modeling can be used to estimate the sizes of clusters. A model for treating the effect of inter-molecular nuclear relaxation upon ionization is proposed. The structure of single-component molecular clusters are investigated by molecular dynamics simulations, validated against XPS data. Finally, the radial structure of a two-component molecular cluster is investigated by XPS.Liquids have been studied for centuries, but still many questions remain regarding the microscopic properties. With the recent development of the liquid microjet technique, new insight into the atomic structure can be obtained. In this thesis we study aqueous solutions using photoelectron and Auger electron spectroscopy (AES). We investigate the structure of surface active molecules by XPS, study the Auger decay after core-level ionization in aqueous potassium chloride (KCl), and follow the changes in molecular structure of glycine as a function of pH.
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| 29. |
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| 30. |
- Bergersen, Henrik, et al.
(författare)
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Two size regimes of methanol clusters produced by adiabatic expansion
- 2006
-
Ingår i: Journal of Chemical Physics. - : AIP Publishing. - 0021-9606 .- 1089-7690. ; 125:18, s. 184303-
-
Tidskriftsartikel (refereegranskat)abstract
- Free neutral methanol clusters produced by adiabatic expansion have been studied by photoelectron spectroscopy and line shape modeling. The results show that clusters belonging to two distinct size regimes can be produced by changing the expansion conditions. While the larger size regime can be well described by line shapes calculated for clusters consisting of hundreds of molecules, the smaller size regime corresponds to methanol oligomers, predominantly of cyclic structure. There is little contribution from dimers to the spectra.
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| 31. |
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| 32. |
- Bjoerstroem, Cecilia M., et al.
(författare)
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Multilayer formation in spin-coated thin films of low-bandgap polyfluorene: PCBM blends
- 2005
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Ingår i: Journal of Physics: Condensed Matter. ; 17:50, s. L529-L534
-
Tidskriftsartikel (refereegranskat)abstract
- Blends of the low-bandgap polymer poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-5,5-(4',7'-di-2-thienyl- 2',1',3'-benzothiadiazole)] (APFO-3) and the fullerene deriv. [6,6]-phenyl-C61-butyric acid Me ester (PCBM) were spin-coated from chloroform soln. into thin films, which were examd. with dynamic secondary ion mass spectrometry. For blends with high PCBM content, the depth profiles show compn. waves that were caused by surface-directed phase sepn. during spin-coating. The formation of such multilayer structures by spontaneous self-stratification probably has implications for optimization strategies for the performance of org. solar cells. [on SciFinder (R)]
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| 33. |
- Björström, Cecilia M., et al.
(författare)
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Multilayer formation in spin-coated thin films of low-bandgap polyfluorene:PCBM blends
- 2005
-
Ingår i: Journal of Physics. - Philadelphia : Institute of Physics Publishing (IOPP). - 0953-8984 .- 1361-648X. ; 17:50, s. L529-L534
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Tidskriftsartikel (refereegranskat)abstract
- Blends of the low-bandgap polymer poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-5,5- (4',7'-di-2-thienyl-2',1',3'-benzothiadiazole] (APFO-3) and the fullerene derivative [6,6]-phenyl–C61–butyric acid methyl ester (PCBM) were spin-coated from chloroform solution into thin films, which were examined with dynamic secondary ion mass spectrometry. For blends with high PCBM content, the depth profiles show composition waves that were caused by surface-directed phase separation during spin-coating. The formation of such multilayer structures by spontaneous self-stratification is likely to have implications for optimization strategies for the performance of organic solar cells
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| 34. |
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| 35. |
- Born, Artur, et al.
(författare)
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Quantification of Ni L-2,L-3 core-hole relaxation pathways utilizing Auger photoelectron coincidence spectroscopy
- 2021
-
Ingår i: Physical Review B. - : American Physical Society. - 2469-9950 .- 2469-9969. ; 103:11
-
Tidskriftsartikel (refereegranskat)abstract
- Ni LVV Auger spectra, in coincidence with the corresponding 2p(1/2), 2p(3/2), and 6 eV satellite photoelectrons, have been used to examine electron correlation and itinerance effects in Ni. In coincidence with the 2p(3/2) core level, the Auger spectral shape is represented by localized 3d(8) and itinerant valence final states with an additional 3d(7) Auger shake-up contribution. The spectra in coincidence with the 6 eV satellite probe the decay of localized 2p(5)3d(9) double hole states, leading to 3d(7) final states. It is found that a fraction of the double hole states delocalize before the Auger decay. A similar delocalization is observed for the double hole states produced by the L2L3M45 Coster-Kronig process, and the delocalization rates have been determined.
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| 36. |
- Bueno, AM, et al.
(författare)
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Influence of chemical bonds on the lifetime of the molecular-field-split 2p levels in H2S
- 2003
-
Ingår i: Physical Review A (Atomic, Molecular and Optical Physics). - 1050-2947. ; 67, s. 22714:1-7
-
Tidskriftsartikel (refereegranskat)abstract
- Different lifetime broadenings in molecular-field-split 2p core levels in H2S are predicted theoretically and are identified in an experimental investigation of the S 2p Auger electron spectrum. The measurements were performed for the transition to the vibrationally resolved X(1)A(1) ground state of H2S2+. The lifetimes of the 3e(1/2) and 5e(1/2) levels of the 2p ionized molecule are found to be 64 and 74 meV, respectively. This unambiguous determination of the lifetime difference of 10+/-1 meV is only possible as the 4e(1/2)-->X(1)A(1)(2b(1)(-2)) decay channel that overlaps the 5e(1/2)-->X(1)A(1)(2b(1)(-2)) channel is practically suppressed in Auger decay in H2S. The lifetime difference is confirmed by ab initio calculations. A theoretical analysis shows that it results from the mutual orientation of the core hole in the intermediate states and the valence electron density in the sulfur 3p orbitals. Both are strongly influenced by the chemical bond. Thus the observed effect is the direct result of a fundamental property of molecular electronic structure.
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| 37. |
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| 38. |
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| 39. |
- Callaghan, Michael, et al.
(författare)
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Codes of ethics artifacts in Australia, Canada and Sweden : A longitudinal study
- 2013
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Ingår i: Looking Forward, Looking Back. - Ruston, LA : Academy of Marketing Science. - 9783319241845 - 9783319241821 ; , s. 108-108
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Konferensbidrag (refereegranskat)abstract
- Based on the Partnership Model of Corporate Ethics (Wood 2002), this longitudinal study examined the measures in place to communicate the ethos of the corporate codes of ethics to internal stakeholders in three countries: Australia, Canada and Sweden. This paper reports the comparative codification of ethics amongst the top companies in these countries over three time periods: 2001-2002, 2005-2006 and 2010-2011.
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| 40. |
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| 41. |
- Cappel, Ute B, et al.
(författare)
-
Electronic structure dynamics in a low bandgap polymer studied by time-resolved photoelectron spectroscopy.
- 2016
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Ingår i: Physical Chemistry, Chemical Physics - PCCP. - : Royal Society of Chemistry. - 1463-9076 .- 1463-9084. ; 18:31, s. 21921-9
-
Tidskriftsartikel (refereegranskat)abstract
- Means to measure the temporal evolution following a photo-excitation in conjugated polymers are a key for the understanding and optimization of their function in applications such as organic solar cells. In this paper we study the electronic structure dynamics by direct pump-probe measurements of the excited electrons in such materials. Specifically, we carried out a time-resolved photoelectron spectroscopy (TRPES) study of the polymer PCPDTBT by combining an extreme ultraviolet (XUV) high harmonic generation source with a time-of-flight spectrometer. After excitation to either the 1st excited state or to a higher excited state, we follow how the electronic structure develops and relaxes on the electron binding energy scale. Specifically, we follow a less than 50 fs relaxation of the higher exited state and a 10 times slower relaxation of the 1st excited state. We corroborate the results using DFT calculations. Our study demonstrates the power of TRPES for studying photo-excited electron energetics and dynamics of solar cell materials.
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| 42. |
- Cappel, Ute B, et al.
(författare)
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Partially Reversible Photoinduced Chemical Changes in a Mixed-Ion Perovskite Material for Solar Cells.
- 2017
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Ingår i: ACS Applied Materials and Interfaces. - : American Chemical Society (ACS). - 1944-8244 .- 1944-8252. ; 9:40, s. 34970-34978
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Tidskriftsartikel (refereegranskat)abstract
- ) with the element specificity and chemical sensitivity of core-level photoelectron spectroscopy. By carrying out measurements at a synchrotron beamline optimized for low X-ray fluxes, we are able to avoid sample changes due to X-ray illumination and are therefore able to monitor what sample changes are induced by visible illumination only. We find that laser illumination causes partially reversible chemistry in the surface region, including enrichment of bromide at the surface, which could be related to a phase separation into bromide- and iodide-rich phases. We also observe a partially reversible formation of metallic lead in the perovskite structure. These processes occur on the time scale of minutes during illumination. The presented methodology has a large potential for understanding light-induced chemistry in photoactive materials and could specifically be extended to systematically study the impact of morphology and composition on the photostability of metal halide perovskites.
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| 43. |
- Carlegrim, Elin, 1979-
(författare)
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Preparation and characterization of an organic-based magnet
- 2007
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In the growing field of spintronics there is a strong need for development of flexible lightweight semi-conducting magnets. Molecular organic-based magnets are attractive candidates since it is possible to tune their properties by organic chemistry, making them so-called “designer magnets”. Vanadium tetracyanoethylene, V(TCNE)x, is particularly interesting since it is a semiconductor with Curie temperature above room temperature (TC~400 K). The main problem with these organic-based magnets is that they are extremely air sensitive. This thesis reports on the frontier electronic structure of the V(TCNE)x by characterization with photoelectron spectroscopy (PES) and near edge x-ray absorption fine structure (NEXAFS) spectroscopy. It also presents a new and more flexible preparation method of this class of organic-based thin film magnets. The result shows improved air stability of the V(TCNE)x prepared with this method as compared to V(TCNE)x prepared by hitherto used methods.
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| 44. |
- Céolin, Denis, et al.
(författare)
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A rotatable electron spectrometer for multicoincidence experiments
- 2010
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Ingår i: Review of Scientific Instruments. - : AIP Publishing. - 1089-7623 .- 0034-6748. ; 81:6
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Tidskriftsartikel (refereegranskat)abstract
- We have developed a rotatable hemispherical spectrometer with good energy and angular resolution, which can be positioned with the lens axis arbitrarily within a solid angle of 1 pi. The collection angle of the emitted electrons with respect to the polarization axis of the light is set by means of a three-axes goniometer, operating under vacuum. An important requirement for this setup was the possibility to perform coincidences between the electron analyzed by the spectrometer and one or several other particles, such as ions, electrons, or photons. The lens system and the hemispheres have been designed to accommodate such experimental demands, regarding parameters such as the resolving power, the acceptance angle, or the width of the kinetic energy window which can be recorded for a given pass energy. We have chosen to detect the impact position of the electron at the focal plane of the hemispherical analyzer with a delay line detector and a time-to-digital converter as acquisition card rather than using a conventional charge-coupled device camera. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3449333]
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| 45. |
- Chatterjee, Sanjukta, 1985-
(författare)
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Structural and Physical Effects of Carbon Nanofillers in Thermoplastic and Thermosetting Polymer Systems
- 2012
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Ever since the discovery of carbon nano materials like carbon nanotube (CNT) and graphene, this class of materials has gained significant attention due to their exotic properties. The principle idea of my present research project is to understand the novel improvements induced in polymer matrices with inclusion of the nanofillers. This thesis is thematically divided into three parts. In the first part we introduce principle materials that we use for preparation of composites. Methods of nanofiller preparation and different nanocomposites as previously reported in literature are discussed to formulate the basis of our study. Different dispersion techniques are discussed which facilitate uniform nanofiller distribution. A variety of experimental methods are described which were employed to investigate the structure and properties of the composites. In the second part we discuss in details polyamide-12 (PA12) composites using CNT and graphene as fillers. A marked improvement is recorded in the toughness of the films with incorporation of CNT, dispersed in PA12 using a surfactant. Electrical percolation is also achieved in the otherwise insulating matrix. With PA-12 fibers we explored the effect of fiber processing and CNT incorporation in the mechanical properties. Extensive wide angle x-ray diffraction was carried out to interpret the structural modifications brought about by CNT in the matrix. The final part of the thesis deals with a thermosetting polymer, epoxy composites. CNT, Graphene and also a mixture of the two nanofillers were used as reinforcing agents. Appreciable improvement was recorded in the mechanical properties, electrical and thermal conductivity of the composites. Detailed optical and electron microscopy was carried out to get a vivid idea of the micro-structure and dispersion. The presented work demonstrates the significant ability of carbon nanofillers to reinforce polymer matrices enhancing their mechanical, electrical and thermal properties and opening a wide horizon for a variety of applications.
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| 46. |
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| 47. |
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| 48. |
- Feifel, Raimund, et al.
(författare)
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From localised to delocalised electronic states in free Ar, Kr and Xe clusters
- 2004
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Ingår i: European Physical Journal D. Atomic, Molecular, Optical and Plasma Physics. - : Springer Science and Business Media LLC. - 1434-6060 .- 1434-6079. ; 30:3, s. 343-351
-
Tidskriftsartikel (refereegranskat)abstract
- We present new results for the inner valence levels of clusters of the three inert gases Ar, Kr and Xe based on photoelectron spectroscopy studies. The inner valence levels are compared to the localised core levels and to the delocalised outer valence levels. This comparison shows a gradual change from a relatively localised behaviour for Ar inner valence 3s, over the intermediate case of Kr inner valence 4s, to a more delocalised behaviour for Xe inner valence 5s. This change correlates well with the ratio between the orbital sizes and the interatomic distances. The Kr4s intermediate case is found to exhibit characteristics of both localised and delocalised behaviour.
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| 49. |
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| 50. |
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