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Seemingly simple yet surprisingly difficult to probe, excess protons in water constitute complex quantum objects with strong interactions with the extended and dynamically changing hydrogen-bonding network of the liquid. Proton hydration plays pivotal roles in energy transport in hydrogen fuel cells and signal transduction in transmembrane proteins. While geometries and stoichiometry have been widely addressed in both experiment and theory, the electronic structure of these specific hydrated proton complexes has remained elusive. Here we show, layer by layer, how utilizing novel flatjet technology for accurate x-ray spectroscopic measurements and combining infrared spectral analysis and calculations, we find orbital-specific markers that distinguish two main electronic-structure effects: Local orbital interactions determine covalent bonding between the proton and neigbouring water molecules, while orbital-energy shifts measure the strength of the extended electric field of the proton. © 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.

Climate change is generally expected to have a positive effect on weathering rates, due to the strong temperature dependence of the weathering process. Important feedback mechanisms such as changes in soil moisture, tree growth and organic matter decomposition can affect the response of weathering rates to climate change. In this study, the dynamic forest ecosystem model ForSAFE, with mechanistic descriptions of tree growth, organic matter decomposition, weathering, hydrology and ion exchange processes, is used to investigate the effects of future climate scenarios on base cation weathering rates. In total, 544 productive coniferous forest sites from the Swedish National Forest Inventory are modelled, and differences in weathering responses to changes in climate from two Global Climate Models are investigated. The study shows that weathering rates at the simulated sites are likely to increase, but not to the extent predicted by a direct response to elevated air temperatures. Besides the result that increases in soil temperatures are less evident than those in air temperature, the study shows that soil moisture availability has a strong potential to limit the expected response to increased temperature. While changes in annual precipitation may not indicate further risk for more severe water deficits, seasonal differences show a clear difference between winters and summers. Taking into account the seasonal variation, the study shows that reduced soil water availability in the summer seasons will strongly limit the expected gain in weathering associated with higher temperatures.

Ion accelerators have demonstrated tremendous versatility in their research applications throughout several decades. Starting predominantly as nuclear physics tools, they subsequently provided novel insights into fundamental atomic physics. Nowadays small and medium size accelerators are routinely employed in several branches of materials science. As research questions increasingly drive the need for analyses and material modification experiments performed in-situ and/or in-operando, facilities must adapt to service such a need. In this work, we highlight capabilities for in-situ and in-operando composition depth profiling and materials modification, developed with instrumentation at the Tandem Laboratory at Uppsala University. An overview of available ion sources and accelerators is given. We then exemplify the specific capabilities of the available end stations for materials synthesis, sample modification and device operation either during simultaneous ion beam based characterization or with such characterization performed in-situ before and after the application of various modification steps. Describing specific recent examples and potential future applications, we illustrate the impact of the present national research infrastructure.

This dissertation covers the development and calibration of the Jovian plasma Dynamics and Composition analyzer (JDC). JDC is together with five other sensors a part of the Particle Environment Package (PEP), one of the payloads of the European Space Agency's JUpiter ICy moons Explorer (JUICE) mission. The JUICE mission is designed to broaden our understanding of the Jovian system including Jupiter, the four Galilean moons (Io, Europa, Ganymede and Callisto) and Jupiter's vast magnetosphere. JUICE is planned to launch in 2023. The PEP payload will study the plasma environment around Jupiter and its moons in great detail. As one of the sensors of PEP, JDC will measure the energy distribution of positive and negative ions as well as electrons in an energy range from a few eV/q up to 35keV/q. The field of view covered by JDC spans over a full hemisphere. JDC also determines the mass of particles using the time-of-flight principle. Alternatively, there is the possibility to determine the distribution of particle arrival times to study their distribution in the time domain. In this thesis, ion-optical, mechanical, electrical, thermal, radiation shielding and instrument operation related design solutions are presented and discussed. Special attention was paid to the performance of the channel electron multipliers used as time-of-flight start detectors. To verify their performance throughout the whole mission, a full lifetime test for these detectors was successfully performed. As a result of this test a qualitative performance model for channel electron multipliers was developed. Another experiment included in this work is the determination of the residual gas pressure evolution inside of JDC. A sufficiently low residual gas pressure is required for safe operation of JDC's high voltage systems. Finally, the performance of the JDC linear electric field reflectron was verified using a dedicated prototype. The last part of this work describes the methods used for instrument, Den här avhandlingen behandlar utvecklingen och kalibreringen av instrumentetJovian plasma Dynamics and Composition analyzer (JDC). JDC utgör tillsammans med fem andra sensorer Particle Environment Package (PEP), som är ett av experimenten på European Space Agency:s rymdsond Jupiter Icy moons Explorer (JUICE). JUICE uppdrag är att bredda och fördjupa vår kunskap om Jupiter-systemet. Rymdsonden ska skjutas upp 2023 och studera Jupiter, Jupiters magnetosfär och de fyra Galileiska månarna (Io, Europa, Ganymedes och Callisto). Instrumentpaketet PEP är konstruerat för att undersöka plasmamiljön kring Jupiter och dess månar i detalj. Sensorn JDC har som sin specifika uppgift att observera energifördelningen hos positiva och negativa joner samt elektroner i ett energiområde från några få eV/q (elektronvolt per laddningsenhet) upp till 35 keV/q. JDC:s synfält är en hel hemisfär och instrumentet använder flygtidsprincipen för att bestämma massorna hos de partiklar som observeras. Det finns också en möjlighet att istället registrera partiklarnas ankomsttider för att titta på fördelningen i tidsdomänen. I avhandlingen presenteras jonoptiska, mekaniska, elektriska och termiska konstruktionslösningar för JDC. Aspekter relaterade till strålningsskärmning och drift av instrumentet diskuteras också. Vi tittar särskilt på prestandan hos de kanalelektronmultiplikatorer som används som startdetektorer i flygtidssystemet. För att undersöka hur de kommer att fungera under den långa expeditionen har ett livstidstest utförts. Utgående från resultaten har en kvalitativ prestandamodell tagits fram. Ett annat experiment som avhandlingen behandlar är undersökningen av hur residualgastrycket utvecklas inuti JDC. För att de högspänningssystem som finns inuti instrumentet ska fungera utan risk för överslag måste trycket vara tillräckligt lågt. Slutligen diskuteras användningen av en särskild prototyp för att verfiera funktionaliteten hos den så kallade ’reflektronen’, en av JDC:s centrala delar., Various Pagination.

Ion accelerators have demonstrated tremendous versatility in their research applications throughout several decades. Starting predominantly as nuclear physics tools, they subsequently provided novel insights into fundamental atomic physics. Nowadays small and medium size accelerators are routinely employed in several branches of materials science. As research questions increasingly drive the need for analyses and material modification experiments performed in-situ and/or in-operando, facilities must adapt to service such a need. In this work, we highlight capabilities for in-situ and in-operando composition depth profiling and materials modification, developed with instrumentation at the Tandem Laboratory at Uppsala University. An overview of available ion sources and accelerators is given. We then exemplify the specific capabilities of the available end stations for materials synthesis, sample modification and device operation either during simultaneous ion beam based characterization or with such characterization performed in-situ before and after the application of various modification steps. Describing specific recent examples and potential future applications, we illustrate the impact of the present national research infrastructure.

In this work, we report on a new lead(II) coordination complex [Pb2L2(CH3CN)(ClO4)2]·2H2O (1·2H2O), which was readily synthesized from a mixture of Pb(ClO4)2·3H2O and 1-(pyridine-2-yl)benzylidene-4-phenylthiosemicarbazide (HL). The crystal structure analysis of 1·2H2O evidenced that the lead(II) cation is N,N',S-chelated by the tridentate pincer type L with formation of a [PbL]+ coordination species, which dimerizes through a couple of reciprocal bridging Pb–S bonds, yielding the [Pb2L2]2+ complex cation. The metal centers within this cation are linked by two Pb∙∙∙N tetrel bonds through the bridging acetonitrile molecule with the formation of a [Pb2L2(CH3CN)]2+ building unit. These units are glued by reciprocal Pb∙∙∙S tetrel bonds, yielding a 1D supramolecular polymeric chain. The lead(II) cations interact also with disordered oxygen atoms of both the minor and major occupancies of the perchlorate anions either through covalent Pb–O bonds or Pb∙∙∙O tetrel bonds, respectively. 1D polymeric chains resemble an expanded hexagonal projection and span along the a axis, yielding a grid-like crystal packing, where the cavities are filled by lattice water molecules. The interactions have been studied using DFT calculations and characterized by using the quantum theory of atoms-in-molecules (QTAIM) and the non-covalent interaction plot (NCIplot) computational tools. © 2022 The Author(s)

Ion accelerators have demonstrated tremendous versatility in their research applications throughout several decades. Starting predominantly as nuclear physics tools, they subsequently provided novel insights into fundamental atomic physics. Nowadays small and medium size accelerators are routinely employed in several branches of materials science. As research questions increasingly drive the need for analyses and material modification experiments performed in-situ and/or in-operando, facilities must adapt to service such a need. In this work, we highlight capabilities for in-situ and in-operando composition depth profiling and materials modification, developed with instrumentation at the Tandem Laboratory at Uppsala University. An overview of available ion sources and accelerators is given. We then exemplify the specific capabilities of the available end stations for materials synthesis, sample modification and device operation either during simultaneous ion beam based characterization or with such characterization performed in-situ before and after the application of various modification steps. Describing specific recent examples and potential future applications, we illustrate the impact of the present national research infrastructure.

Water resources are of great importance in the world's agriculture, especially regarding the scarcity of these resources. That calls for attention appropriate for analysis, study, and research in all issues and aspects that would contribute to the development and maintenance of those resources and achieve the maximum possible levels of quality and efficiency of use. The study was conducted during the fall season of 2020 to study groundwater quality (well water) in the city of Al-Qaim of Anbar Province to explain its suitability for agricultural exploitation in the region. The study included seven sites in Al-Qaim (Rtemi, Medicis, Eastern Akash, Okesha, Sawab, Albu-Hayat, and Al-Karah) to assess the validity of irrigation. The pH, Electrical conductivity (EC), positive ions (K+, Na+, Mg2+, Ca2+), and negative ions (HCO3, Cl-2, SO4) and CO3 were measured. The results showed that the studied well water is acceptable for irrigation purposes in terms of pH value, as for the electrical connection, it was six wells within the class (C2), which is adequate for irrigation for medium-salty crops, except for one well, which is a fine well within class C3 suitable for irrigation of high salinity crops. The total hardness values were low and did not pose any risk; as for the positive and negative ions, they were within the permissible limits within the specified classifications. By measuring the positive ions, the Sodium Adsorption Ratio (SAR) value was calculated and determined to be within the class S1, which means that the groundwater in the region is suitable for irrigation., Validerad;2022;Nivå 1;2022-04-27 (sofila)

This dissertation covers the development and calibration of the Jovian plasma Dynamics and Composition analyzer (JDC). JDC is together with five other sensors a part of the Particle Environment Package (PEP), one of the payloads of the European Space Agency's JUpiter ICy moons Explorer (JUICE) mission. The JUICE mission is designed to broaden our understanding of the Jovian system including Jupiter, the four Galilean moons (Io, Europa, Ganymede and Callisto) and Jupiter's vast magnetosphere. JUICE is planned to launch in 2023. The PEP payload will study the plasma environment around Jupiter and its moons in great detail. As one of the sensors of PEP, JDC will measure the energy distribution of positive and negative ions as well as electrons in an energy range from a few eV/q up to 35keV/q. The field of view covered by JDC spans over a full hemisphere. JDC also determines the mass of particles using the time-of-flight principle. Alternatively, there is the possibility to determine the distribution of particle arrival times to study their distribution in the time domain. In this thesis, ion-optical, mechanical, electrical, thermal, radiation shielding and instrument operation related design solutions are presented and discussed. Special attention was paid to the performance of the channel electron multipliers used as time-of-flight start detectors. To verify their performance throughout the whole mission, a full lifetime test for these detectors was successfully performed. As a result of this test a qualitative performance model for channel electron multipliers was developed. Another experiment included in this work is the determination of the residual gas pressure evolution inside of JDC. A sufficiently low residual gas pressure is required for safe operation of JDC's high voltage systems. Finally, the performance of the JDC linear electric field reflectron was verified using a dedicated prototype. The last part of this work describes the methods used for instrument, Den här avhandlingen behandlar utvecklingen och kalibreringen av instrumentetJovian plasma Dynamics and Composition analyzer (JDC). JDC utgör tillsammans med fem andra sensorer Particle Environment Package (PEP), som är ett av experimenten på European Space Agency:s rymdsond Jupiter Icy moons Explorer (JUICE). JUICE uppdrag är att bredda och fördjupa vår kunskap om Jupiter-systemet. Rymdsonden ska skjutas upp 2023 och studera Jupiter, Jupiters magnetosfär och de fyra Galileiska månarna (Io, Europa, Ganymedes och Callisto). Instrumentpaketet PEP är konstruerat för att undersöka plasmamiljön kring Jupiter och dess månar i detalj. Sensorn JDC har som sin specifika uppgift att observera energifördelningen hos positiva och negativa joner samt elektroner i ett energiområde från några få eV/q (elektronvolt per laddningsenhet) upp till 35 keV/q. JDC:s synfält är en hel hemisfär och instrumentet använder flygtidsprincipen för att bestämma massorna hos de partiklar som observeras. Det finns också en möjlighet att istället registrera partiklarnas ankomsttider för att titta på fördelningen i tidsdomänen. I avhandlingen presenteras jonoptiska, mekaniska, elektriska och termiska konstruktionslösningar för JDC. Aspekter relaterade till strålningsskärmning och drift av instrumentet diskuteras också. Vi tittar särskilt på prestandan hos de kanalelektronmultiplikatorer som används som startdetektorer i flygtidssystemet. För att undersöka hur de kommer att fungera under den långa expeditionen har ett livstidstest utförts. Utgående från resultaten har en kvalitativ prestandamodell tagits fram. Ett annat experiment som avhandlingen behandlar är undersökningen av hur residualgastrycket utvecklas inuti JDC. För att de högspänningssystem som finns inuti instrumentet ska fungera utan risk för överslag måste trycket vara tillräckligt lågt. Slutligen diskuteras användningen av en särskild prototyp för att verfiera funktionaliteten hos den så kallade ’reflektronen’, en av JDC:s centrala delar., Various Pagination.

Water resources are of great importance in the world's agriculture, especially regarding the scarcity of these resources. That calls for attention appropriate for analysis, study, and research in all issues and aspects that would contribute to the development and maintenance of those resources and achieve the maximum possible levels of quality and efficiency of use. The study was conducted during the fall season of 2020 to study groundwater quality (well water) in the city of Al-Qaim of Anbar Province to explain its suitability for agricultural exploitation in the region. The study included seven sites in Al-Qaim (Rtemi, Medicis, Eastern Akash, Okesha, Sawab, Albu-Hayat, and Al-Karah) to assess the validity of irrigation. The pH, Electrical conductivity (EC), positive ions (K+, Na+, Mg2+, Ca2+), and negative ions (HCO3, Cl-2, SO4) and CO3 were measured. The results showed that the studied well water is acceptable for irrigation purposes in terms of pH value, as for the electrical connection, it was six wells within the class (C2), which is adequate for irrigation for medium-salty crops, except for one well, which is a fine well within class C3 suitable for irrigation of high salinity crops. The total hardness values were low and did not pose any risk; as for the positive and negative ions, they were within the permissible limits within the specified classifications. By measuring the positive ions, the Sodium Adsorption Ratio (SAR) value was calculated and determined to be within the class S1, which means that the groundwater in the region is suitable for irrigation., Validerad;2022;Nivå 1;2022-04-27 (sofila)

The hydrogen-bonding interaction is studied in imidazolium-based mesogenic ionic liquids in their isotropic, smectic, and solid phases and in a nanoconfined state by proton solid-state nuclear magnetic resonance (NMR). In the smectic phase, the more basic anions form stronger hydrogen bonds. A small decrease of H-bonding in the mesophase with respect to that in the isotropic phase is associated with the presence of a layered assembly with high orientational order and limited conformational freedom. Hydrogen bond strength is not sensitive to the cation structural modification as long as the aprotic nature of the material is preserved. The strong cation-anion hydrogen bonding observed in the smectic phases provides direct support for the presence of ionic sublayers which form in ionic liquid crystals regardless of the location and alignment of the charged group in the cation, particularly irrespective of whether the charged group occupies a terminal or central position in the cation structure. A comparison of the results obtained in isotropic, liquid-crystalline, and solid states shows that in the bulk materials the dynamic state of ions ranging from high reorientational and translational freedom to partial orientation and positional order to full immobilization, respectively, has no strong impact on the cation-anion hydrogen bond strength. On the other hand, nanoconfinement of ionic liquid crystals led to hydrogen bond disruption due to competing interactions of anions with a solid interface., QC 20230602

Ion accelerators have demonstrated tremendous versatility in their research applications throughout several decades. Starting predominantly as nuclear physics tools, they subsequently provided novel insights into fundamental atomic physics. Nowadays small and medium size accelerators are routinely employed in several branches of materials science. As research questions increasingly drive the need for analyses and material modification experiments performed in-situ and/or in-operando, facilities must adapt to service such a need. In this work, we highlight capabilities for in-situ and in-operando composition depth profiling and materials modification, developed with instrumentation at the Tandem Laboratory at Uppsala University. An overview of available ion sources and accelerators is given. We then exemplify the specific capabilities of the available end stations for materials synthesis, sample modification and device operation either during simultaneous ion beam based characterization or with such characterization performed in-situ before and after the application of various modification steps. Describing specific recent examples and potential future applications, we illustrate the impact of the present national research infrastructure.

Ion accelerators have demonstrated tremendous versatility in their research applications throughout several decades. Starting predominantly as nuclear physics tools, they subsequently provided novel insights into fundamental atomic physics. Nowadays small and medium size accelerators are routinely employed in several branches of materials science. As research questions increasingly drive the need for analyses and material modification experiments performed in-situ and/or in-operando, facilities must adapt to service such a need. In this work, we highlight capabilities for in-situ and in-operando composition depth profiling and materials modification, developed with instrumentation at the Tandem Laboratory at Uppsala University. An overview of available ion sources and accelerators is given. We then exemplify the specific capabilities of the available end stations for materials synthesis, sample modification and device operation either during simultaneous ion beam based characterization or with such characterization performed in-situ before and after the application of various modification steps. Describing specific recent examples and potential future applications, we illustrate the impact of the present national research infrastructure.

This dissertation covers the development and calibration of the Jovian plasma Dynamics and Composition analyzer (JDC). JDC is together with five other sensors a part of the Particle Environment Package (PEP), one of the payloads of the European Space Agency's JUpiter ICy moons Explorer (JUICE) mission. The JUICE mission is designed to broaden our understanding of the Jovian system including Jupiter, the four Galilean moons (Io, Europa, Ganymede and Callisto) and Jupiter's vast magnetosphere. JUICE is planned to launch in 2023. The PEP payload will study the plasma environment around Jupiter and its moons in great detail. As one of the sensors of PEP, JDC will measure the energy distribution of positive and negative ions as well as electrons in an energy range from a few eV/q up to 35keV/q. The field of view covered by JDC spans over a full hemisphere. JDC also determines the mass of particles using the time-of-flight principle. Alternatively, there is the possibility to determine the distribution of particle arrival times to study their distribution in the time domain. In this thesis, ion-optical, mechanical, electrical, thermal, radiation shielding and instrument operation related design solutions are presented and discussed. Special attention was paid to the performance of the channel electron multipliers used as time-of-flight start detectors. To verify their performance throughout the whole mission, a full lifetime test for these detectors was successfully performed. As a result of this test a qualitative performance model for channel electron multipliers was developed. Another experiment included in this work is the determination of the residual gas pressure evolution inside of JDC. A sufficiently low residual gas pressure is required for safe operation of JDC's high voltage systems. Finally, the performance of the JDC linear electric field reflectron was verified using a dedicated prototype. The last part of this work describes the methods used for instrument, Den här avhandlingen behandlar utvecklingen och kalibreringen av instrumentetJovian plasma Dynamics and Composition analyzer (JDC). JDC utgör tillsammans med fem andra sensorer Particle Environment Package (PEP), som är ett av experimenten på European Space Agency:s rymdsond Jupiter Icy moons Explorer (JUICE). JUICE uppdrag är att bredda och fördjupa vår kunskap om Jupiter-systemet. Rymdsonden ska skjutas upp 2023 och studera Jupiter, Jupiters magnetosfär och de fyra Galileiska månarna (Io, Europa, Ganymedes och Callisto). Instrumentpaketet PEP är konstruerat för att undersöka plasmamiljön kring Jupiter och dess månar i detalj. Sensorn JDC har som sin specifika uppgift att observera energifördelningen hos positiva och negativa joner samt elektroner i ett energiområde från några få eV/q (elektronvolt per laddningsenhet) upp till 35 keV/q. JDC:s synfält är en hel hemisfär och instrumentet använder flygtidsprincipen för att bestämma massorna hos de partiklar som observeras. Det finns också en möjlighet att istället registrera partiklarnas ankomsttider för att titta på fördelningen i tidsdomänen. I avhandlingen presenteras jonoptiska, mekaniska, elektriska och termiska konstruktionslösningar för JDC. Aspekter relaterade till strålningsskärmning och drift av instrumentet diskuteras också. Vi tittar särskilt på prestandan hos de kanalelektronmultiplikatorer som används som startdetektorer i flygtidssystemet. För att undersöka hur de kommer att fungera under den långa expeditionen har ett livstidstest utförts. Utgående från resultaten har en kvalitativ prestandamodell tagits fram. Ett annat experiment som avhandlingen behandlar är undersökningen av hur residualgastrycket utvecklas inuti JDC. För att de högspänningssystem som finns inuti instrumentet ska fungera utan risk för överslag måste trycket vara tillräckligt lågt. Slutligen diskuteras användningen av en särskild prototyp för att verfiera funktionaliteten hos den så kallade ’reflektronen’, en av JDC:s centrala delar., Various Pagination.

The synthesis and crystallographic site occupancy were investigated for MgAl2O4 with and without mechanical activation of the precursor powders. Heating to 1200 °C or higher resulted in the formation of a single spinel phase regardless of whether the powders were mechanically activated or not. Neutron diffraction analysis was used to determine cation site occupancy and revealed that mechanical activation resulted in a lower degree of cation site inversion compared to the nonactivated materials, which indicated that the powders were closer to thermodynamic equilibrium. This is the first study to characterize the effects of mechanical activation on crystallographic site occupancy in magnesium aluminate spinel using neutron diffraction. © 2022 by the authors.

This dissertation covers the development and calibration of the Jovian plasma Dynamics and Composition analyzer (JDC). JDC is together with five other sensors a part of the Particle Environment Package (PEP), one of the payloads of the European Space Agency's JUpiter ICy moons Explorer (JUICE) mission. The JUICE mission is designed to broaden our understanding of the Jovian system including Jupiter, the four Galilean moons (Io, Europa, Ganymede and Callisto) and Jupiter's vast magnetosphere. JUICE is planned to launch in 2023. The PEP payload will study the plasma environment around Jupiter and its moons in great detail. As one of the sensors of PEP, JDC will measure the energy distribution of positive and negative ions as well as electrons in an energy range from a few eV/q up to 35keV/q. The field of view covered by JDC spans over a full hemisphere. JDC also determines the mass of particles using the time-of-flight principle. Alternatively, there is the possibility to determine the distribution of particle arrival times to study their distribution in the time domain. In this thesis, ion-optical, mechanical, electrical, thermal, radiation shielding and instrument operation related design solutions are presented and discussed. Special attention was paid to the performance of the channel electron multipliers used as time-of-flight start detectors. To verify their performance throughout the whole mission, a full lifetime test for these detectors was successfully performed. As a result of this test a qualitative performance model for channel electron multipliers was developed. Another experiment included in this work is the determination of the residual gas pressure evolution inside of JDC. A sufficiently low residual gas pressure is required for safe operation of JDC's high voltage systems. Finally, the performance of the JDC linear electric field reflectron was verified using a dedicated prototype. The last part of this work describes the methods used for instrument, Den här avhandlingen behandlar utvecklingen och kalibreringen av instrumentetJovian plasma Dynamics and Composition analyzer (JDC). JDC utgör tillsammans med fem andra sensorer Particle Environment Package (PEP), som är ett av experimenten på European Space Agency:s rymdsond Jupiter Icy moons Explorer (JUICE). JUICE uppdrag är att bredda och fördjupa vår kunskap om Jupiter-systemet. Rymdsonden ska skjutas upp 2023 och studera Jupiter, Jupiters magnetosfär och de fyra Galileiska månarna (Io, Europa, Ganymedes och Callisto). Instrumentpaketet PEP är konstruerat för att undersöka plasmamiljön kring Jupiter och dess månar i detalj. Sensorn JDC har som sin specifika uppgift att observera energifördelningen hos positiva och negativa joner samt elektroner i ett energiområde från några få eV/q (elektronvolt per laddningsenhet) upp till 35 keV/q. JDC:s synfält är en hel hemisfär och instrumentet använder flygtidsprincipen för att bestämma massorna hos de partiklar som observeras. Det finns också en möjlighet att istället registrera partiklarnas ankomsttider för att titta på fördelningen i tidsdomänen. I avhandlingen presenteras jonoptiska, mekaniska, elektriska och termiska konstruktionslösningar för JDC. Aspekter relaterade till strålningsskärmning och drift av instrumentet diskuteras också. Vi tittar särskilt på prestandan hos de kanalelektronmultiplikatorer som används som startdetektorer i flygtidssystemet. För att undersöka hur de kommer att fungera under den långa expeditionen har ett livstidstest utförts. Utgående från resultaten har en kvalitativ prestandamodell tagits fram. Ett annat experiment som avhandlingen behandlar är undersökningen av hur residualgastrycket utvecklas inuti JDC. För att de högspänningssystem som finns inuti instrumentet ska fungera utan risk för överslag måste trycket vara tillräckligt lågt. Slutligen diskuteras användningen av en särskild prototyp för att verfiera funktionaliteten hos den så kallade ’reflektronen’, en av JDC:s centrala delar., Various Pagination.

This dissertation covers the development and calibration of the Jovian plasma Dynamics and Composition analyzer (JDC). JDC is together with five other sensors a part of the Particle Environment Package (PEP), one of the payloads of the European Space Agency's JUpiter ICy moons Explorer (JUICE) mission. The JUICE mission is designed to broaden our understanding of the Jovian system including Jupiter, the four Galilean moons (Io, Europa, Ganymede and Callisto) and Jupiter's vast magnetosphere. JUICE is planned to launch in 2023. The PEP payload will study the plasma environment around Jupiter and its moons in great detail. As one of the sensors of PEP, JDC will measure the energy distribution of positive and negative ions as well as electrons in an energy range from a few eV/q up to 35keV/q. The field of view covered by JDC spans over a full hemisphere. JDC also determines the mass of particles using the time-of-flight principle. Alternatively, there is the possibility to determine the distribution of particle arrival times to study their distribution in the time domain. In this thesis, ion-optical, mechanical, electrical, thermal, radiation shielding and instrument operation related design solutions are presented and discussed. Special attention was paid to the performance of the channel electron multipliers used as time-of-flight start detectors. To verify their performance throughout the whole mission, a full lifetime test for these detectors was successfully performed. As a result of this test a qualitative performance model for channel electron multipliers was developed. Another experiment included in this work is the determination of the residual gas pressure evolution inside of JDC. A sufficiently low residual gas pressure is required for safe operation of JDC's high voltage systems. Finally, the performance of the JDC linear electric field reflectron was verified using a dedicated prototype. The last part of this work describes the methods used for instrument, Den här avhandlingen behandlar utvecklingen och kalibreringen av instrumentetJovian plasma Dynamics and Composition analyzer (JDC). JDC utgör tillsammans med fem andra sensorer Particle Environment Package (PEP), som är ett av experimenten på European Space Agency:s rymdsond Jupiter Icy moons Explorer (JUICE). JUICE uppdrag är att bredda och fördjupa vår kunskap om Jupiter-systemet. Rymdsonden ska skjutas upp 2023 och studera Jupiter, Jupiters magnetosfär och de fyra Galileiska månarna (Io, Europa, Ganymedes och Callisto). Instrumentpaketet PEP är konstruerat för att undersöka plasmamiljön kring Jupiter och dess månar i detalj. Sensorn JDC har som sin specifika uppgift att observera energifördelningen hos positiva och negativa joner samt elektroner i ett energiområde från några få eV/q (elektronvolt per laddningsenhet) upp till 35 keV/q. JDC:s synfält är en hel hemisfär och instrumentet använder flygtidsprincipen för att bestämma massorna hos de partiklar som observeras. Det finns också en möjlighet att istället registrera partiklarnas ankomsttider för att titta på fördelningen i tidsdomänen. I avhandlingen presenteras jonoptiska, mekaniska, elektriska och termiska konstruktionslösningar för JDC. Aspekter relaterade till strålningsskärmning och drift av instrumentet diskuteras också. Vi tittar särskilt på prestandan hos de kanalelektronmultiplikatorer som används som startdetektorer i flygtidssystemet. För att undersöka hur de kommer att fungera under den långa expeditionen har ett livstidstest utförts. Utgående från resultaten har en kvalitativ prestandamodell tagits fram. Ett annat experiment som avhandlingen behandlar är undersökningen av hur residualgastrycket utvecklas inuti JDC. För att de högspänningssystem som finns inuti instrumentet ska fungera utan risk för överslag måste trycket vara tillräckligt lågt. Slutligen diskuteras användningen av en särskild prototyp för att verfiera funktionaliteten hos den så kallade ’reflektronen’, en av JDC:s centrala delar., Various Pagination.

To reduce undesired iron leaching in Fenton reaction and to realize reusability of catalyst, chitosan-coated activated carbon cloth support loaded with nano zero-valent iron (ACC–CH–nZVI) was applied as a heterogeneous Fenton catalyst to treat melanoidin wastewater. Chitosan coating on ACC by chemical crosslinking results in 6% chitosan on ACC subsequently loading 3.5% iron. At optimum conditions, ACC–CH–nZVI leads to 88.4% and 76.2% of color and chemical oxygen demand (COD) removal, respectively, upon treating synthetic melanoidin wastewater of 8000 mg/l COD. The corresponding weight ratio of consumed H2O2 to COD is 1.02, far below the stoichiometric ratio 2.125, indicating the economic value of this catalyst. Reusability of ACC–CH–nZVI is demonstrated for five cycles of treatment with minimal iron leaching (<2%). The high removal efficiency and very low levels of iron leaching suggests that ACC–CH–nZVI is a highly efficient and cost-effective catalyst for Fenton-like oxidation of non-biodegradable organic wastes in water., QC 20201202

In this work we report a new Hg(II) coordination compound [Hg(HL)(SCN)2], which was readily obtained from a mixture of Hg(SCN)2 and N'-(1-(pyridin-2-yl)ethylidene)nicotinohydrazide (HL). The metal cation is chelated by the organic ligand in a N,N',O tridentate manner through the 2-Py and amide nitrogen donors, and carbonyl oxygen atom. The coordination sphere is filled by the sulfur donors of two thiocyanate anions, thus yielding a pentacoordinated geometry, which is best described as being about 64% along the pathway of distortion from the ideal square pyramidal toward trigonal bipyramidal structure. In addition, the metal center forms two types of the Hg⋯N spodium bonds, which are formed with the 3-Py nitrogen atom of a symmetry related molecule and with the nitrogen atom of one thiocyanate ligand of another molecular unit. These Hg⋯N spodium bonds enlarge the coordination environment of the metal cation in between a capped trigonal prism close to pentagonal bipyramid. In addition a 1D zig-zag-like polymeric chain is formed, which is further reinforced by bilateral C–H⋯O hydrogen bonds. These chains are interlinked through N–H⋯N hydrogen bonds and additionally glued by π⋯π interactions between the 2-Py rings. Thus, considering all the Hg⋯N spodium and N–H⋯N hydrogen bonds, a supramolecular 2D layer is formed with a binodal 3,4-connected hcb topology. The 2D layers are interlinked through a myriad of π⋯π interactions. According to the Hirshfeld surface analysis, the crystal packing of [Hg(HL)(SCN)2] is mainly characterized by intermolecular H⋯H, H⋯C, H⋯N and H⋯S contacts comprised from 15.9 to 22.3%, followed by less significant H⋯O, C⋯C, C⋯N, N⋯S and Hg⋯N contacts comprised from 2.8 to 6.3%. The intermolecular H⋯C, H⋯N, H⋯O, H⋯S and C⋯C contacts are highly favoured in the molecular surface of [Hg(HL)(SCN)2], while the N⋯S contacts are less favoured, and remaining contacts are significantly impoverished. Finally, density functional theory (DFT) calculations at the

Electrolytic deposition (ELD) and electrophoretic deposition (EPD) are relevant methods for creating functional layers of solid oxide fuel cells (SOFCs). This review discusses challenges, new findings and prospects for the implementation of these methods, with the main emphasis placed on the use of the ELD method. Topical issues concerning the formation of highly active SOFC electrodes using ELD, namely, the electrochemical introduction of metal cations into a porous electrode backbone, the formation of composite electrodes, and the electrochemical synthesis of perovskite-like electrode materials are considered. The review presents examples of the ELD formation of the composite electrodes based on porous platinum and silver, which retain high catalytic activity when used in the low-temperature range (400–650 °C). The features of the ELD/EPD co-deposition in the creation of nanostructured electrode layers comprising metal cations, ceramic nanoparticles, and carbon nanotubes, and the use of EPD to create oriented structures are also discussed. A separate subsection is devoted to the electrodeposition of CeO2-based film structures for barrier, protective and catalytic layers using cathodic and anodic ELD, as well as to the main research directions associated with the deposition of the SOFC electrolyte layers using the EPD method. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

Lead halide perovskites have become a leading material in the field of emerging photovoltaics and optoelectronics. Significant progress has been achieved in improving the intrinsic properties and environmental stability of these materials. However, the stability of lead halide perovskites to ionising radiation has not been widely investigated. In this study, we investigated the radiolysis of lead halide perovskites with organic and inorganic cations under X-ray irradiation using synchrotron based hard X-ray photoelectron spectroscopy. We found that fully inorganic perovskites are significantly more stable than those containing organic cations. In general, the degradation occurs through two different, but not mutually exclusive, pathways/mechanisms. One pathway is induced by radiolysis of the lead halide cage into halide salts, halogen gas and metallic lead and appears to be catalysed by defects in the perovskite. The other pathway is induced by the radiolysis of the organic cation which leads to formation of organic degradation products and the collapse of the perovskite structure. In the case of Cs0.17FA0.83PbI3, these reactions result in products with a lead to halide ratio of 1 : 2 and no formation of metallic lead. The radiolysis of the organic cation was shown to be a first order reaction with regards to the FA+ concentration and proportional to the X-ray flux density with a radiolysis rate constant of 1.6 × 10-18 cm2 per photon at 3 keV or 3.3 cm2 mJ-1. These results provide valuable insight for the use of lead halide perovskite based devices in high radiation environments, such as in space environments and X-ray detectors, as well as for investigations of lead halide perovskites using X-ray based techniques., QC 20220318

Ameso-functionalization strategy has successfully been applied to the synthesis of novel 1,3,7-triazapyrene derivatives of calixarenes. The key synthetic step in these transformations providing the direct C-C bond formation is nucleophilic substitution of hydrogen (SNH) in 1,3,7-triazapyrene. General photophysical characteristics for these macrocyclic compounds, as well as features in emission properties upon addition of various metal cations have been elaborated. Studies using NMR spectroscopy have also shown a mutual effect of both calix[4]arene and 1,3,7-triazapyrene moieties on the coordination process. The complex stoichiometry and binding constants for Al3+and Fe3+guests have been explored with titration experiments. © The Royal Society of Chemistry 2021.

Biochars have been shown as promising materials for cadmium remediation. However, the different precursors and the pyrolysis process operating conditions can yield very different surface functional groups, and as a result, different cadmium sorption mechanisms can be observed in biochars. Herein we present the results of cadmium sorption on biochars produced from the pyrolysis of different agro-residues, namely, coffee husk, quinoa straw, and oil palm kernel shell. The adsorption isotherms were used to determine the influence of the biochar's physicochemical characteristics to their sorption behavior. The biochars prepared from quinoa residues showed much higher cadmium uptakes than the other biochars. The concentration of base cations was found to be a critical factor for cadmium sorption. Although the quinoa biochars presented large uptakes, it was found that base cations were supported on the biochars and could be removed by leaching. Results from this study suggest that concentration of base cations on biochars could be used as predictors of the biochar capabilities for the removal of cadmium in aqueous solution. Copyright © 2020 American Chemical Society.

Biochars have been shown as promising materials for cadmium remediation. However, the different precursors and the pyrolysis process operating conditions can yield very different surface functional groups, and as a result, different cadmium sorption mechanisms can be observed in biochars. Herein we present the results of cadmium sorption on biochars produced from the pyrolysis of different agro-residues, namely, coffee husk, quinoa straw, and oil palm kernel shell. The adsorption isotherms were used to determine the influence of the biochar's physicochemical characteristics to their sorption behavior. The biochars prepared from quinoa residues showed much higher cadmium uptakes than the other biochars. The concentration of base cations was found to be a critical factor for cadmium sorption. Although the quinoa biochars presented large uptakes, it was found that base cations were supported on the biochars and could be removed by leaching. Results from this study suggest that concentration of base cations on biochars could be used as predictors of the biochar capabilities for the removal of cadmium in aqueous solution. Copyright © 2020 American Chemical Society.

Molecularly imprinted polymers have emerged as cost-effective and rugged artificial selective sorbents for combination with different sensors. In this study, quaternary ammonium cations, as functional monomers, were systematically evaluated to design imprinted polymers for glyphosate as an important model compound for electrically charged and highly water-soluble chemical compounds. To this aim, a small pool of monomers were used including (3-acrylamidopropyl)trimethylammonium chloride, [2-(acryloyloxy)ethyl]trimethylammonium chloride, and diallyldimethylammonium chloride. The simultaneous interactions between three positively charged monomers and glyphosate were preliminary evaluated using statistical design of the experiment method. Afterwards, different polymers were synthesized at the gold surface of the quartz crystal microbalance sensor using optimized and not optimized glyphosate-monomers ratios. All synthesized polymers were characterized using atomic force microscopy, contact angle, Fourier-transform infrared, and X-ray photoelectron spectroscopy. Evaluated functional monomers showed promise as highly efficient functional monomers, when they are used together and at the optimized ratio, as predicted by the statistical method. Obtained results from the modified sensors were used to develop a simple model describing the binding characteristics at the surface of the different synthesized polymers. This model helps to develop new synthesis strategies for rational design of the highly selective imprinted polymers and to use as a sensing platform for water soluble and polar targets. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

A detailed study on the single-molecule ferroelectric property of Preyssler-type polyoxometalates (POMs), [M3+P5W30O110](12-) (M = La, Gd, and Lu), is performed by density functional theory calculations. Linked to one H2O molecule, the cation (M3+) encapsulated in the cavity of the Preyssler framework is off-centered, and it generates a permanent dipole, which is essential for a ferroelectric ground state. Accompanied with a 180 degrees rotation of H2O, the switching of M3+ between two isoenergetic sites on both sides of the cavity results in a calculated barrier of 1.15 eV for Gd3+, leading to the inversion of electric polarization. The height of the barrier is in good agreement with the experimentally measured barrier for the Tb3+ ion, whose ionic radius is similar to Gd3+. The total polarization value of the crystal is estimated to be 4.7 mu C/cm(2) as calculated by the modern theory of polarization, which is quite close to the experimental value. Considering that the order of contributions to the polarization is M3+-H2O > counter-cations (K+) > [P5W30O110](15-), the interconversion of M3+-H2O between the two isoenergetic sites is predicted to be the main origin of ferroelectricity with a polarization contribution of 3.4 mu C/cm(2); the K+ counter-cations contribute by 1.2 mu C/cm(2) and it cannot be disregarded, while the framework appears to contribute negligibly to the total polarization. Our study suggests that a suitable choice of M3+-H2O could be used to tune the single-molecule ferroelectricity in Preyssler-type polyoxometalates.

We report on the development of a novel laser crystal with broadband emission properties at similar to 2 mu m - a Tm3+, Li+-codoped calcium tantalum gallium garnet (Tm:CLTGG). The crystal is grown by the Czochralski method. Its structure (cubic, sp. gr . la (3) over bard, a = 12.5158(0) angstrom) is refined by the Rietveld method. Tm:CLTGG exhibits a relatively high thermal conductivity of 4.33 Wm(-1) K-1. Raman spectroscopy confirms a weak concentration of vacancies due to the charge compensation provided by Li+ codoping. The transition probabilities of Tm3+ ions are determined using the modified Judd-Ofelt theory yielding the intensity parameters Omega(2) = 5.185, Omega(4) = 0.650, Omega(6) = 1.068 [10(-20) cm(2)] and alpha = 0.171 [10(-4) cm]. The crystal-field splitting of the Tm3+ multiplets is revealed at 10 K. The first diode-pumped Tm:CLTGG laser generates 1.08 W at similar to 2 mu m with a slope efficiency of 23.8%. The Tm3+ ions in CLTGG exhibit significant inhomogeneous spectral broadening due to the structure disorder (a random distribution of Ta5+ and Ga3+ cations over octahedral and tetrahedral lattice sites) leading to smooth and broad gain profiles (bandwidth: 130 nm) extending well above 2 mu m and rendering Tm:CLTGG suitable for femtosecond pulse generation. (C) 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

Dendronized polyethers give rise to columnar LC structures which can successfully act as cation transport materials. Therefore, we prepared two different materials, based on Poly(epichlorohydrin-co-ethylene oxide) (PECH-co-EO) grafted with methyl 3,4,5-tris[4-(n-dodecan-1-yloxy)benzyloxy] benzoate, containing 20% or 40% modified units, respectively. The obtained polymers were characterized by differential scanning calorimetry (DSC), X-ray diffraction and optical microscopy between crossed polars (POM) and compared to the unmodified PECH-co-EO. In order to reach efficient transport properties, homeotropically oriented membranes were prepared by a fine-tuned thermal annealing treatment and were subsequently investigated by dynamic mechanical thermal analysis (DMTA) and dielectric thermal analysis (DETA). We found that the presence of the dendrons induces a main chain partial crystallization of the polyether chain and coherently increases the polymer Tg. This effect is more evident in the oriented membranes. As for copolymer orientation upon annealing, the cooling rate and the annealing temperature were the most crucial factors. DMTA and DETA confirmed that grafting with the dendron strongly hinders copolymer motions, but did not show great differences between unoriented and oriented membranes, regardless of the amount of dendrons.

This study presents a novel mixed-mode weak cation-exchange (WCX) material. This material was prepared by means of the functionalization of a mesoporous divinylbenzene (DVB) resin with maleic acid (maleic acid-DVB), which yielded a high carboxylic moiety content resulting in WCX interactions as well as suitable specific surface area for reversed-phase interactions. After the optimization of the solid-phase extraction (SPE) protocol to enhance the selectivity of the sorbent, this material was evaluated as a novel WCX sorbent in the SPE of a group of drugs from environmental water samples. The method is based on SPE followed by liquid chromatography (LC) coupled to high resolution mass spectrometry (HRMS) with an Orbitrap analyzer, and was validated and applied for the determination of basic drugs in river, effluent and influent wastewater samples. Maleic acid-DVB sorbent yielded suitable recovery rates (57% to 89%) and an acceptable matrix effect ( < 32%) thanks to the effective washing step included when these environmental waters were loaded through the novel resin. The method was applied to different environmental water samples and some basic drugs were suitably quantified in these environmental samples. (c) 2021 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ )

Pr2NiO4+δ oxide with a layered Ruddlesden–Popper structure is a promising material for SOFC cathodes and oxygen separation membranes due to a high oxygen mobility provided by the cooperative mechanism of oxygen migration involving both interstitial oxygen species and apical oxygen of the NiO6 octahedra. Doping by Ca improves thermodynamic stability and increases electronic conductivity of Pr2 − xCaxNiO4+δ, but decreases oxygen mobility due to decreasing the oxygen excess and appearing of 1–2 additional slow diffusion channels at x ≥ 0.4, probably, due to hampering of cooperative mechanism of migration. However, atomic-scale features of these materials determining oxygen migration require further studies. In this work characteristics of oxygen diffusion in Pr2 − xCaxNiO4+δ (x = 0–0.6) are compared with results of the surface analysis by X-ray photoelectron spectroscopy and modeling of the interstitial oxygen migration by the plane-wave density functional theory calculations. According to the X-ray photoelectron spectroscopy data, the surface is enriched by Pr for undoped sample and by Ca for doped ones. The O1s peak at ~531 eV corresponding to a weakly bound form of surface oxygen located at Pr cations disappears at ~500 °C. Migration of interstitial oxygen was modeled for a I4/mmm phase of Pr2NiO4+δ. The interstitial oxygen anion repulses the apical one in the NiO6 octahedra pushing it into the tetrahedral site between Pr cations. The calculated activation barrier of this migration is equal to 0.585 eV, which reasonably agrees with the experimental value of 0.83 eV obtained by the oxygen isotope exchange method. At the same time, for the model compound Ca2NiO4+δ, obtained by isomorphic substitution of Pr by Ca in Pr2NiO4+δ, calculations implied formation of the peroxide ion comprised of interstitial and lattice oxygen species not revealed in the case of incomplete substitution (up to PrCaNiO4+δ composition). Hence, calculations in the framework of the plane-wave den

The motivation of this work is driven by the feasible hydrogen production, through the reaction between iron-bearing phases, i.e. RO phase, metallic Fe in steel slag and steam. The RO phase can be regarded as (Mn,Mg,Ca)xFe1-xO wüstite that divalent iron is partially substituted by foreign cations of magnesium, manganese and calcium. The reaction behavior in terms of hydrogen generation variation in the temperature range of 500–1000 °C has been studied. It was found that the hydrogen production rate was strongly temperature dependent. Under isothermal conditions, the steel slag-steam reaction proceeded rapidly during the first 2000s. Beyond this, the rate of the reaction decreased significantly due to the formation of (Mg,Mn,Ca)yFe3-yO4 ferrite layer. The theoretical hydrogen generation capacity for steel slag was found to be proportional to the substitution level of foreign cations, i.e. Mg, Mn, Ca in wüstite. The underlying phase transitions, as well as the structural changes were discussed in detail by combing the XRD, SEM-EDS, XPS and VSM analysis. The kinetics analysis showed that the slag-steam reaction agreed well with the three-dimensional diffusion (D3) model and the corresponding activation energy for diffusion was estimated as 105.76 kJ/mol. Moreover, it was noticed that the magnetic properties of steel slag after steam oxidation was greatly enhanced, and the maximum specific magnetic susceptibility was 1.8E-4 m3/kg at 800 °C. This demonstrated steam oxidation could significantly improve the magnetism of steel slag and provide the possibility of iron recovering through magnetic separation. Based on the findings, the novel concept of the steam modification process towards highly efficient utilization of steel slag along its cooling path was proposed. It allowed us to envision the potentials that implementing management of energy production, iron recovery, and volumetric stabilization., QC 20200322

A concept of interlayer-sensitized photoluminescence (PL) of quasi-2D hybrid perovskite (PVK) with a π-conjugated optically interacting organic cation layer is introduced and demonstrated. A rod-shaped aggregation-induced enhanced emission (AIEE) organic cation (BPCSA+), well fitted into the lattice size of 2D PVK layers, is designed and synthesized to prolong the exciton lifetime in a condensed layer assembly in the PVK. The BPCSA+ promotes the PL of this hybrid PVK up to 10-folds from that of a non-π-conjugated organic cation (OA) 2D PVK. Notably, different from PL of OA 2D PVK, the increased PL intensity of BPCSA 2D PVKs with an increase of the BPCSA ratio in the PVK indicates a critical photon-harvesting contribution of BPCSA. The films of BPCSA 2D PVKs are incredibly stable in ambient environments for more than 4 months and even upon direct contact with water. Additionally, due to the strong two-photon absorption property of BPCSA, the BPCSA 2D PVK displays superior emission properties upon two-photon excitation with a short wavelength IR laser. Thus, the AIEE sensitization system for quasi-2D PVK hybrid system can make a drastic improvement in performance as well as in the stability of the PVK emitter and PVK based nonlinear optical devices., QC 20200630

The domain switching by ion beam irradiation of single-domain Y-cut plates of congruent lithium niobate doped by 5 mol% MgO was studied. Dot irradiation resulted in the formation of wedge-like domains grown along Z- polar direction. The nonlinear dependences of the domain sizes on irradiation conditions were obtained. The model of domain growth on non-polar cut was proposed in frame of kinetic approach. The absence of the domain merging along Z- polar direction was attributed to the deceleration of the forward growth by electrostatic interaction of the positive charges at the charged domain walls and injected positive ions. © 2020, © 2020 Taylor & Francis Group, LLC.

The dehydration of the CPO-27-M (M-MOF-74, M = Zn, Co, Ni, Mg, Mn, Cu) metal-organic framework series has been investigated comprehensively using in situ variable temperature powder X-ray diffraction (VT-PXRD) and thermal analysis (TG) coupled with mass spectrometry (MS). Significant differences in the order of water desorption from different adsorption sites on heating are found with varying metal cation in the otherwise isostructural material. For all CPO-27-M (except M = Cu), water is bonded significantly more strongly to the accessible open metal sites, and these water molecules are only desorbed at higher temperatures than the other water molecules. CPO-27-Cu is an exception, where all water molecules desorb simultaneously and at much lower temperatures (below 340 K). MS and TG data show that all CPO-27-M start to release traces of CO2 already at 300–350 K, and thus long before bulk thermal decomposition is observed. Only for CPO-27-Co, the CO2 release is essentially constant on its baseline between 450 and 700 K, and it is the only CPO-27-M member that shows a stable plateau in the TG in this region. Additional rehydration studies on CPO-27-Co show that the MOF incorporates any water molecules present until the pores are fully loaded. CPO-27-Co consequently behaves as an efficient trap for any water present.

The single-phase oxide PrBaCo 2 O 6−δ and composites (100 − y)PrBaCo 2 O 6−δ -yCe 0.8 Sm 0.2 O 1.9 (y = 10–30 wt.%) were investigated as cathode materials for intermediate-temperature solid oxide fuel cells. The chemical compatibility, cation interdiffusion, thermal expansion and dc conductivity were studied. As a result, strong interdiffusion of Pr and Sm was found between PrBaCo 2 O 6−δ and Ce 0.8 Sm 0.2 O 1.9 . This leads to only insignificantly decreasing thermal expansion coefficient of composite with increasing fraction of Ce 0.8 Sm 0.2 O 1.9 and, thus, mixing PrBaCo 2 O 6−δ with Ce 0.8 Sm 0.2 O 1.9 does not improve thermal expansion behavior of the cathode material. Moreover, formation of poorly-conducting BaCeO 3 , caused by chemical interaction between the double perovskite and doped ceria, was shown to lead to pronounced drop in the electrical conductivity of the composite cathode material with increasing Ce 0.8 Sm 0.2 O 1.9 content. © 2019 by the authors.

Design of materials for solid oxide fuel cells cathodes and oxygen separation membranes and studying their oxygen transport characteristics are important problems of modern hydrogen energy. In the current work, fundamentals of such materials design based on characterization of their oxygen mobility by oxygen isotope exchange with C18O2 and 18O2 in flow and closed reactors for samples of Ruddlesden - Popper-type oxides Ln2-xCaxNiO4+δ, perovskite-fluorite nanocomposites PrNi0.5Co0.5O3-δ - Ce0.9Y0.1O2-δ, etc. are presented. Fast oxygen transport was demonstrated for PNC - YDC (DO ~10-8 cm2/s at 700°C) nanocomposites due to domination of the fast diffusion channel involving oxygen of the fluorite phase with incorporated Pr cations and developed perovskite-fluorite interfaces. For LnCNO materials a high oxygen mobility (DO ~10-7 cm2/s at 700°C) provided by the cooperative mechanism of its migration was demonstrated. Depending on Ca dopant content and Ln cation nature, in some cases 1-2 additional channels of the slow diffusion appear due to decreasing the interstitial oxygen content and increasing the energy barrier for oxygen jumps due to cationic size effect. Optimized by the chemical composition and nanodomain structure materials of these types demonstrated a high performance as SOFC cathodes and functional layers in asymmetric supported oxygen separation membranes. © The Authors, published by EDP Sciences, 2019.

Monoethylene glycol (MEG) regeneration plants often use pretreatment vessels to precipitate divalent cations, such as Fe2+, Ca2+, and Mg2+, in order to avoid or reduce fouling in downstream reboilers and heat exchangers. This pretreatment process operates under alkaline conditions and moderate temperatures (~ 80 °C) to accelerate the formation of low-solubility divalent salts. The objective of the present research was to determine whether the pretreatment process could be minimized, without negatively impacts on the MEG regeneration process from to the formation of scale on the heater bundle in the presence of low concentrations of divalent cations in the rich MEG stream. Scale formation was analyzed under MEG regeneration process conditions using a dynamic scale loop (DSL) test and verification experiments were performed in a MEG regeneration and reclamation pilot plant, both with and without pretreatment conditions. The scaling tendencies of several rich MEG–brine mixtures were evaluated at different pH pretreatment levels and dissolved CO2 concentrations. An evaluation temperature of 180 °C was chosen to match the skin temperature of the reboiler heater bundle during the MEG regeneration process. The experiments of pH 7.24 showed high amounts of precipitation scale within the reboiler due to high remaining concentrations of mineral ions. In addition, small concentrations of calcium and magnesium ions led to the precipitation of calcite, dolomite, and magnesium hydroxide on the reboiler bundle and within associated filtered outputs even when a pretreatment vessel was present. These results were confirmed by the differential pressure build-up and Scanning Electron Microscopy analyses for each experimental condition. Another interesting finding is that pH increased within the reboiler due to CO2 gas boiling off at high operating temperatures, thus contributing to increased alkalinity levels, which in turn promoted scale formation. These results indicate that pretrea

Monoethylene glycol (MEG) regeneration plants often use pretreatment vessels to precipitate divalent cations, such as Fe2+, Ca2+, and Mg2+, in order to avoid or reduce fouling in downstream reboilers and heat exchangers. This pretreatment process operates under alkaline conditions and moderate temperatures (~ 80 °C) to accelerate the formation of low-solubility divalent salts. The objective of the present research was to determine whether the pretreatment process could be minimized, without negatively impacts on the MEG regeneration process from to the formation of scale on the heater bundle in the presence of low concentrations of divalent cations in the rich MEG stream. Scale formation was analyzed under MEG regeneration process conditions using a dynamic scale loop (DSL) test and verification experiments were performed in a MEG regeneration and reclamation pilot plant, both with and without pretreatment conditions. The scaling tendencies of several rich MEG–brine mixtures were evaluated at different pH pretreatment levels and dissolved CO2 concentrations. An evaluation temperature of 180 °C was chosen to match the skin temperature of the reboiler heater bundle during the MEG regeneration process. The experiments of pH 7.24 showed high amounts of precipitation scale within the reboiler due to high remaining concentrations of mineral ions. In addition, small concentrations of calcium and magnesium ions led to the precipitation of calcite, dolomite, and magnesium hydroxide on the reboiler bundle and within associated filtered outputs even when a pretreatment vessel was present. These results were confirmed by the differential pressure build-up and Scanning Electron Microscopy analyses for each experimental condition. Another interesting finding is that pH increased within the reboiler due to CO2 gas boiling off at high operating temperatures, thus contributing to increased alkalinity levels, which in turn promoted scale formation. These results indicate that pretrea

There is an urgent need for reliable seawater phosphate measuring tools to better assess eutrophication. Today, most accepted sensing approaches are based on the established colorimetric molybdenum blue assay. It requires one to modify the sample to strongly acidic conditions and to add various reagents, principally molybdate and reducing agent (e.g., ascorbic acid), to form a blue colored phosphate complex that is subsequently detected spectrophotometrically. The associated need for large sample and mobile phase reservoirs and mixing coils are, unfortunately, not ideally adapted for the development of operationally simple in situ sensing instruments. It is here demonstrated for the first time that the key reagents needed to achieve phosphate detection by the molybdate method may be delivered by passive counter transport across ion-exchange membranes. A cation-exchange Donnan exclusion membrane placed in contact with a sample flow (450 μm thick) is shown to provide the strongly acidic conditions (pH ∼ 1) necessary for phosphate determination. Proton transport is driven, via cation-exchange, by the high sodium content of the seawater sample. Molybdate was similarly released through an anion-exchange membrane by chloride counter transport. Consequently, an in-line flow system containing the two membrane modules in series was used for delivering both hydrogen and molybdate ions into the sample to form the desired phosphomolybdate complex for subsequent spectrophotometric detection. A linear calibration in the range of 0.1-10 μM phosphate (3-300 ppb inorganic P) was achieved, which is sufficiently attractive for environmental work. A range of seawater samples was tested and the results from this membrane delivery device showed no significant differences compared to the classical molybdate assay chosen as the reference method., QC 20190625

Absorption modes and the reactivity of nonhalogenated ionic liquids (ILs) at inorganic oxide surfaces of γ-Al2O3, MgO, and SiO2 particles were characterized using multinuclear (11B, 31P, and 29Si) solid-state magic-angle-spinning NMR, FTIR, and Raman spectroscopy. ILs are composed of the trihexyl(tetradecyl)phosphonium cation, [P6,6,6,14]+, and bis(mandelato)borate, [BMB]-, or bis(salicylato)borate, [BScB]-, anions. Spectroscopic measurements were performed on room-temperature (298 K) samples and samples exposed to 15 h at 373 K. The single-pulse 11B NMR data of heated [P6,6,6,14][BMB] mixed with the inorganic oxides showed a significant change in the spectra of the anion for all three oxides. In contrast, no such spectral changes were detected for heated [P6,6,6,14][BScB] mixed with the inorganic oxides. 31P MAS NMR data for the IL/metal oxide systems revealed interactions between [P6,6,6,14]+ and the surfaces of oxides. A significant intensity of 31P CP-MAS NMR signals indicated a low mobility of cations in these systems. The existence of strongly adhered surface layers of ILs on SiO2 particles was also confirmed by 1H-29Si CP-MAS NMR spectroscopy. FTIR and Raman spectroscopic data revealed strong interactions between the anions and the inorganic surfaces, and there is a strong correlation with the data obtained from NMR spectroscopy. Although their chemical structures are rather similar, the [BScB]- anion is more stable than the [BMB]- anion at the inorganic oxide surfaces., Export Date: 22 October 2018; Article; Correspondence Address: Shah, F.U.; Chemistry of Interfaces, Luleå University of TechnologySweden; email: faisha@ltu.se; Funding details: LTU, Luther Theological University; Funding details: 621-2013-5171, VR, Vetenskapsrådet; Funding details: 621-2014-4694, VR, Vetenskapsrådet; Funding details: KAW2012.0078, Knut och Alice Wallenbergs Stiftelse; Funding text: The Knut and Alice Wallenberg Foundation (project number KAW2012.0078), Swedish Research Council (projects numbers 621-2013-5171 (O.N.A. and F.U.S.) and 621-2014-4694 (S.G.)), and the Norrbotten Research Council (NoFo) are gratefully acknowledged for supporting this work. We also thank the Foundation in memory of J. C. and Seth M. Kempe and the laboratory fond at LTU for providing grants, from which FTIR and Raman spectrometers have been purchased and a Varian/Chemagnetics CMX-360 NMR spectrometer at LTU has been upgraded. QC 20181022

In this work we have experimentally studied the impact of bentonite clay on the process of radiation-induced copper corrosion in anoxic water. The motivation for this is to further develop our understanding of radiation-driven processes occurring in deep geological repositories for spent nuclear fuel where copper canisters containing the spent nuclear fuel will be embedded in compacted bentonite. Experiments on radiation-induced corrosion in the presence and absence of bentonite were performed along with experiments elucidating the impact irradiation on the Cu2+ adsorption capacity of bentonite. The experiments presented in this work show that the presence of bentonite clay has no or very little effect on the magnitude of radiation-induced corrosion of copper in anoxic aqueous systems. The absence of a protective effect similar to that observed for radiation-induced dissolution of UO2 is attributed to differences in the corrosion mechanism. This provides further support for the previously proposed mechanism where the hydroxyl radical is the key radiolytic oxidant responsible for the corrosion of copper. The radiation effect on the bentonite sorption capacity of Cu2+ (reduced capacity) is in line with what has previously been reported for other cations. The reduced cation sorption capacity is partly attributed to a loss of Al-OH sites upon irradiation., Export Date: 13 February 2018; Article; CODEN: RPCHD; Correspondence Address: Jonsson, M.; School of Chemical Science and Engineering, Applied Physical Chemistry, KTH Royal Institute of TechnologySweden; email: matsj@kth.se; Funding details: SKB, Svensk Kärnbränslehantering. QC 20180326

A terpyridine- and guanine-functionalized peptide was developed that could form different morphologies by self-assembly or coordination with Fe2+ in dimethyl sulfoxide. The self-assembly of the peptide is attributed to the G-quartet formation of a guanine moiety and intermolecular terpyridine π-π stacking. Upon the addition of Fe2+, a Fe2+-(terpyridine)2 complex is formed that turns the square-planar self-assembly to a three-dimensional self-assembly. As a consequence, a variety of interesting morphologies and chemical properties were observed. The self-assembled polymers were studied by nuclear magnetic resonance spectroscopy, ultraviolet-visible and fluorescence spectroscopy, viscosity measurement, circular dichroism, Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, dynamic light scattering, and atomic force microscopy. This external stimuli driven self-assembly of a peptide may be further applied to drug delivery applications., Export Date: 13 February 2018; Article; Correspondence Address: Wu, J.; Key Laboratory for Advanced Materials, Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science and TechnologyChina; email: jcwu@ecust.edu.cn; Funding details: CSC, China Scholarship Council; Funding details: 21778017; Funding details: 91529101; Funding details: 21572057. QC 20180227

We present a combined experimental and theoretical study of the photodissociation of the bisanthenequinone (C28H12O2) cation, Bq+. The experiments show that, upon photolysis, the Bq+ cation does not dehydrogenate, but instead fragments through the sequential loss of the two neutral carbonyl groups, causing the formation of five-membered carbon cycles. Quantum chemical calculations confirm this Bq+ → [Bq - CO]+ → [Bq - 2CO]+ sequence as the energetically most favorable reaction pathway. For the first CO loss, a transition state with a barrier of ∼3.2 eV is found, substantially lower than the lowest calculated H loss dissociation pathway (∼4.9 eV). A similar situation applies for the second CO loss channel (∼3.8 eV vs. ∼4.7 eV), but where the first dissociation step does not strongly alter the planar PAH geometry, the second step transforms the molecule into a bowl-shaped one., Export Date: 13 February 2018; Article; CODEN: CHPLB; Correspondence Address: Chen, T.; Department of Theoretical Chemistry and Biology, School of Biotechnology, Royal Institute of TechnologySweden; email: chen@strw.leidenuniv.nl; Funding details: 2015-06501, VR, Vetenskapsrådet. QC 20180228

New tripod-type 2,2′-bipyridine ligand consisting of a central polyaminocarboxylic moiety for the coordination to lanthanide cations and three appended 5-phenyl-2,2′-bipyridine fragments for the coordination to various transition metal cations have been prepared. A europium complex of this ligand was prepared, and its photophysical properties and a luminescent response towards transition metal salts (particularly, CdI2, Cd(OAc)2, Zn(ClO4)2, Cu(OAc)2, and HgCl2) have been studied. Europium cation luminescence quenching in the presence of transition metal salts in solution was observed in all cases. In addition, it was observed that the fluorescent response of the europium complex was quite individual depending on the type of the metal salt. The obtained data were compared with the earlier published data for some lanthanide complexes bearing additional sites for the chelation of transition metal cations. © 2018 Published by NRC Research Press.

It is well documented that the interlayer space of clay minerals, notably smectites (e.g., montmorillonite), can be intercalated with wide variety of inorganic cations or organic cations through ion exchange reactions or using other physical and chemical means of interaction. When the modification of smectite is performed with organic cations, their properties change from hydrophilic to hydrophobic. Therefore, the resulting materials become efficient sorbents of organic contaminants in wastewater, e.g., as sorbing materials in landfill liners etc. Organophilic montmorillonite is prepared through exchange of smectite interlayer cations with long chain (C16-C18) alkylammonium-based ions (surfactants). Ionic liquids containing long chain cations (mostly imidazolium based) are another alternative to conventional nanoparticle modifiers. The review provides an overview of available clay based intercalated materials with various ionic liquids and surfactants, their effectiveness in removal of organic contaminants, and potential applications in environmentally friendly technologies. Present review is providing a platform for understanding the structure, properties and potential applications of organically modified clay materials, especially emphasizing water treatment. © SGEM2018.

Here, 15 LnF3 nanocrystals are synthesized using coprecipitation method with citrate stabilization to allow the fast, easy, and reproducible synthesis of several nanoscaled structures in water. General trends related to the behavior of LnF3 nanocrystals are highlighted due to their broad range of application in several fields (e.g., medical applications). The same nature for all Ln3+ cations is expected due to the internal role of f orbitals. However, we found that the use of different lanthanide elements is crucial in the final size, shape, assembly, and crystalline structure. In addition, the decrease of the cation size of the lanthanide series changes the behavior of these compounds, resulting in hexagonal, orthorhombic, and cubic crystalline structures. In addition, we are able to tune the cubic crystalline phase to pure orthorhombic by modifying the pH of the system using HBF4 instead of tetramethylammonium citrate. Via 11B NMR, we demonstrated the mechanism of HBF4 as fluorinating agent if an additional source of F– is not added during the synthesis. 1H NMR and IR techniques were performed to unravel the picture of the surface chemistry of the two representative metal cations (Y and La). Finally, HRTEM and SAED were performed to uncover the shape of the obtained nanocrystals and the preferential orientation of the assembled particles, giving crucial information on the involved mechanisms. This study reveals not only the dependence of the crystalline structure on the used metal and pH but also ability to achieve LnF3 assembled particles depending on the final shape and temperature.

Two-dimensional (2D) layered materials with a high intercalation pseudocapacitance have long been investigated for Li+-ion-based electrochemical energy storage. By contrast, the exploration of guest ions other than Li+ has been limited, although promising. The present study investigates intercalation/deintercalation behaviors of various metal ions in 2D layered MnO2 with various interlayer distances, K-birnessite nanobelt (K-MnO2), its protonated form (H-MnO2), and a freeze-dried sample of exfoliated nanosheets. Series of metal ions, such as monovalent Li+, Na+, and K+ and divalent Mg2+, exhibit reversible intercalation during charge/discharge cycling, delivering high-rate pseudocapacitances. In particular, the freeze-dried MnO2 of exfoliated nanosheets restacked with the largest interlayer spacing and a less compact 3D network exhibits the best rate capability and a stable cyclability over 5000 cycles. Both theoretical calculation and kinetic analysis reveal that the increased interlayer distance facilitates the fast diffusion of cations in layered MnO2 hosts. The results presented herein provide a basis for the controllable synthesis of layered nanostructures for high-rate electrochemical energy storage using various single- and multivalent ions., QC 2017-06-08

A new ditopic ligand based on diethylenetriamine-N,N,N'',N''-tetraacetate (DTTA) and 5-phenyl-2,2′-bipyridine has been synthesized. The improved method for the synthesis of DTTA tert-butyl ester has been developed. The water-soluble Eu3+∗DTTA complex of this ligand has been prepared, and its photophysical properties have been studied. Due to the presence of an extra chelating unit, 5-phenyl-2,2′-bipyridine, this Eu3+∗DTTA complex demonstrated a strong fluorescence response to the Zn2+ cation (fluorescence enhancement) and the simultaneous fluorescent and phosphorescent response (fluorescence and phosphorescence quenching) to the Cu2+ or Ni2+ cations in aqueous solutions. © 2016 Published by NRC Research Press.

Atomistic simulations have been performed to investigate the microscopic structural organization of aqueous solutions of trihexyltetradecylphosphonium bis(oxalato)borate ([P6,6,6,14][BOB]) ionic liquid (IL). The evolution of the microscopic liquid structure and the local ionic organization of IL/water mixtures as a function of the water concentration is visualized and systematically analyzed via radial and spatial distribution functions, coordination numbers, hydrogen bond network, and water clustering analysis. The microscopic liquid structure in neat IL is characterized by a connected apolar network composed of the alkyl chains of [P6,6,6,14] cations and isolated polar domains consisting of the central segments of [P6,6,6,14] cations and [BOB] anions, and the corresponding local ionic environment is described by direct contact ion pairs. In IL/water mixtures with lower water mole fractions, the added water molecules are dispersed and embedded in cavities between neighboring ionic species and the local ionic structure is characterized by solvent-shared ion pairs through cation-water-anion triple complexes. With a gradual increase in the water concentration in IL/water mixtures, the added water molecules tend to aggregate and form small clusters, intermediate chain-like structures, large aggregates, and eventually a water network in water concentrated simulation systems. A further progressive dilution of IL/water mixtures leads to the formation of self-organized micelle-like aggregates characterized by a hydrophobic core and hydrophilic shell consisting of the central polar segments in [P6,6,6,14] cations and [BOB] anions in a highly branched water network. The striking structural evolution of the [P6,6,6,14][BOB] IL/water mixtures is rationalized by the competition between favorable hydrogen bonded interactions and strong electrostatic interactions bet, QC 20150601

Alkylammonium lead(ii) iodide materials (APbI3), based on the general formula of CH3-(CH2)n-NH3PbI3, may lead to a monumental leap in developing affordable photovoltaics. Herein, we correlate the structure and function relationships of alkylammonium lead(ii) iodide in solar cells. We investigated changes in the structure of APbI3 materials by varying the alkylammonium cations in their structure. As the size of the alkylammonium cation increased, the crystallographic unit cell increased in size and yielded lower symmetry crystals. High symmetry materials, those with cubic symmetry, showed the highest conductivity, the smallest bandgap, and produced the best performing solar cells. Structural changes were investigated by X-ray crystallography, X-ray powder diffraction, and Raman scattering., QC 20150602.Correction in: Journal of Materials Chemistry A, vol. 3, issue 17, page 9317. Doi: 10.1039/c5ta90073e, WOS: 000353420800051, Scopus: 2-s2.0-84928485590