New insights into water's phase diagram using ammonium fluoride

Ice is a complex, yet highly relevant material and has been a rife area of research since the beginning of the 20th century.1-5 Understanding ice is expected to have consequences not just for furthering our appreciation of the different states of water, but also general chemistry, physics and geology.2, 6, 7 It has often been found that properties first observed in ice (e.g. stacking disorder) are also present in other materials.2, 6, 8, 9 This thesis largely builds on work performed by Shephard et al. which explored the effect of 2.5 mol% NH4F in ice, and astoundingly fully prevented ice II formation.10 Initially, the thesis focuses on the effect of adding NH4F to ice at ambient pressure, which is demonstrated to produce a denser material than pure ice. At 0.5 GPa, NH4F-ice solid solutions (≥ 12 mol%) surprisingly produce stable ice XII-type structures. Additionally, upon the mapping of the 2.5 mol% NH4F phase diagram to 1.7 GPa, it was found that phase-pure ice XII could be quenched at 1.1 GPa. Both ice XIItype structures did not require an amorphous precursor. The influence of NH4F in ice is explored in mixtures that are subjected to the compression conditions that yield high-density amorphous ice ‘pressure-induced amorphised’ upon their compression to 1.4 GPa at 77 K. Unexpectedly, the crossover of PIA to recrystallisation is determined as beginning on the water-rich side (35 mol% NH4F) of the solid solutions. Stacking disorder from the heating of NH4F II and III at ambient pressure is quantified. The materials reach a maximum cubicity of 77%, yet the stacking disorder obtained from each material is unique. Remarkably NH4F III did not transform to an amorphous phase upon heating. The final standalone chapter focuses on the ordering of ices V/XIII and IX with 0.01 M HCl doping

Meetings with refugees

Bachelor sykepleie, 2018Bakgrunn: Flyktninger kommer ofte fra krigsland og opplever turtur, fengsel og vanskeligheter før, under og etter flukten. Dette kan føre til at disse menneskene er traumatiserte og på grunn av dette får en psykiatrisk lidelse som diagnose. De traumatiske opplevelsene påvirker flyktningers hverdag og livskvalitet. Hensikt: Vi ønsker å finne ut av hvilke utfordringer som kan oppstå i møtet mellom sykepleier og flyktninger, og hvordan det kan påvirke kommunikasjon mellom dem. I tillegg ønsker vi å finne ut hvordan sykepleiere kan bidra til å skape gode møter med traumatiserte flyktninger som er innlagt i et psykiatrisk avdeling. Problemstilling: Hvordan kan vi som sykepleiere bidra til å skape best mulige møter med traumatiserte flyktninger ved hjelp av god kommunikasjon? Metode: Oppgaven er en litteraturstudie med et selvvalgt tema som bygger på pensumlitteratur, selvvalgt faglitteratur, forskningsartikler, praksis og personlige erfaringer. Resultat: De største utfordringene sykepleiere står overfor i møte med traumatiserte flyktninger er kommunikasjon på grunn av språkutfordringer- og kulturforskjeller. Kommunikasjonsutfordringer kan føre til at sykepleiere får vanskeligheter med å skape tillit, trygghet og tilfredsstillende møter med flyktninger. Konklusjon: Vi har kommet fram til at kommunikasjonsutfordringer kan oppstå på grunn av språkbarriere og pasientens kulturelle bakgrunn i møte mellom sykepleiere og flyktninger. Å bestille profesjonell tolk kan være en løsning når det kommer til språkutfordringer. Å samle kulturelle data kan hjelpe sykepleier å få kunnskap om pasientens tro, etnisitet, bakgrunn, livssyn, sykdomsoppfatning, holdninger og annen relevant bakgrunnsinformasjon. Menneske- til- menneske- forholdet kan hjelpe sykepleiere til å få innsikt og forståelse for pasientens opplevelser og hvordan de opplevelsene har påvirket pasientens hverdag

Ammonium Fluoride as a Hydrogen-disordering Agent for Ice

The removal of residual hydrogen disorder from various phases of ice with acid or base dopants at low temperatures has been a focus of intense research for many decades. As an antipode to these efforts, we now show using neutron diffraction that ammonium fluoride (NH4F) is a hydrogen-disordering agent for the hydrogen-ordered ice VIII. Cooling its hydrogen-disordered counterpart ice VII doped with 2.5 mol% ND4F under pressure leads to a hydrogen-disordered ice VIII with ~31% residual hydrogen disorder illustrating the long-range hydrogen-disordering effect of ND4F. The doped ice VII could be supercooled by ~20 K with respect to the hydrogen-ordering temperature of pure ice VII after which the hydrogen-ordering took place slowly over a ~60 K temperature window. These findings demonstrate that ND4F-doping slows down the hydrogen-ordering kinetics quite substantially. The partial hydrogen order of the doped sample is consistent with the antiferroelectric ordering of pure ice VIII. Yet, we argue that local ferroelectric domains must exist between ionic point defects of opposite charge. In addition to the long-range effect of NH4F-doping on hydrogen-ordered water structures, the design principle of using topological charges should be applicable to a wide range of other 'ice-rule' systems including spin ices and related polar materials.Comment: 23 pages, 4 figures, 2 table

Hybrid Organic-Inorganic Coordination Complexes as Tunable Optical Response Materials.

Novel lead and bismuth dipyrido complexes have been synthesized and characterized by single-crystal X-ray diffraction, which shows their structures to be directed by highly oriented π-stacking of planar fully conjugated organic ligands. Optical band gaps are influenced by the identity of both the organic and inorganic component. Density functional theory calculations show optical excitation leads to exciton separation between inorganic and organic components. Using UV-vis, photoluminescence, and X-ray photoemission spectroscopies, we have determined the materials' frontier energy levels and show their suitability for photovoltaic device fabrication by use of electron- and hole-transport materials such as TiO2 and spiro-OMeTAD respectively. Such organic/inorganic hybrid materials promise greater electronic tunability than the inflexible methylammonium lead iodide structure through variation of both the metal and organic components

Møter med flyktninger

Bakgrunn: Flyktninger kommer ofte fra krigsland og opplever turtur, fengsel og vanskeligheter før, under og etter flukten. Dette kan føre til at disse menneskene er traumatiserte og på grunn av dette får en psykiatrisk lidelse som diagnose. De traumatiske opplevelsene påvirker flyktningers hverdag og livskvalitet. Hensikt: Vi ønsker å finne ut av hvilke utfordringer som kan oppstå i møtet mellom sykepleier og flyktninger, og hvordan det kan påvirke kommunikasjon mellom dem. I tillegg ønsker vi å finne ut hvordan sykepleiere kan bidra til å skape gode møter med traumatiserte flyktninger som er innlagt i et psykiatrisk avdeling. Problemstilling: Hvordan kan vi som sykepleiere bidra til å skape best mulige møter med traumatiserte flyktninger ved hjelp av god kommunikasjon? Metode: Oppgaven er en litteraturstudie med et selvvalgt tema som bygger på pensumlitteratur, selvvalgt faglitteratur, forskningsartikler, praksis og personlige erfaringer. Resultat: De største utfordringene sykepleiere står overfor i møte med traumatiserte flyktninger er kommunikasjon på grunn av språkutfordringer- og kulturforskjeller. Kommunikasjonsutfordringer kan føre til at sykepleiere får vanskeligheter med å skape tillit, trygghet og tilfredsstillende møter med flyktninger. Konklusjon: Vi har kommet fram til at kommunikasjonsutfordringer kan oppstå på grunn av språkbarriere og pasientens kulturelle bakgrunn i møte mellom sykepleiere og flyktninger. Å bestille profesjonell tolk kan være en løsning når det kommer til språkutfordringer. Å samle kulturelle data kan hjelpe sykepleier å få kunnskap om pasientens tro, etnisitet, bakgrunn, livssyn, sykdomsoppfatning, holdninger og annen relevant bakgrunnsinformasjon. Menneske- til- menneske- forholdet kan hjelpe sykepleiere til å få innsikt og forståelse for pasientens opplevelser og hvordan de opplevelsene har påvirket pasientens hverdag

Antifungal activity in the methanolic, aqueous and hexane extracts of

The use of plants to cure specific ailments is as antique as human civilization. These days, in the modern era, there is a growing concern by public opinion regarding the use of synthetic medicine due to their side effects and cost. These facts led to the discovery of some economical and alternative drugs with fewer side-effects. In this study, methanolic, hexane and aqueous extracts of Capparis deciduas have been evaluated for their antifungal activity against medically important fungal strains – Candida albicans and Aspergillus niger using disc diffusion method at a dose of 1.8, 2.9, 6.5, 12.6, 25, 50 and 75 (µg/mL). Zone of inhibition for antifungal activity of these extracts was compared with that of a standard drug like fluconazole. The methanolic extracts of C. decidua showed significant activity against C. albicans (minimum inhibitory concentration (MIC): 1.8 µg/mL), for hexane extracts the MIC was 2.9 µg/mL and for aqueous extracts, no MIC can be observed. C. decidua did not show significant activity against A. niger . Our finding showed that C. decidua has antifungal activity and further phytochemical analyses of these plants should be carried out to determine the bioactive ingredients that may serve as a lead in the progress of novel research activities in the pharmaceuticals industry

Observation of the Reversible Ice III to Ice IX Phase Transition by Using Ammonium Fluoride as Anti-Ice II Agent

Ice III is a hydrogen-disordered phase of ice that is stable between about 0.2 and 0.35 GPa. Upon cooling, it transforms to its hydrogen-ordered counterpart ice IX within the stability region of ice II. Because of this metastability, detailed studies of the ice III to ice IX phase transition have so far not been carried out. Using ammonium fluoride doping to prevent the formation of ice II, we now present a detailed study on this phase transition using in-situ powder neutron diffraction. The a and c lattice constants are found to expand and contract, respectively, upon hydrogen ordering yielding an overall negative volume change. Interestingly, the anisotropy in the lattice constants persists when ice IX is fully formed and negative thermal expansion is observed. Analogous to the isostructural keatite and b-spodumenes, the negative thermal expansion can be explained through the build-up of torsional strain within in the a-b plane as the helical ‘springs’ within the structure expand upon heating. The reversibility of the phase transition was demonstrated for the first time upon heating. The ammonium fluoride doping induces additional residual hydrogen disorder in ice IX and is suggested to be a chemical way for ‘excitation’ of the ice-rules configurational manifold. Compared to ices II and VIII, the induced hydrogen disorder in ice IX is smaller which suggests a higher density of configurational states close to the ground state. This study highlights the importance of dopants for exploring water’s phase diagram and underpins the highly complex solid-state chemistry of ice

Phytoremediation of Cadmium: Physiological, Biochemical, and Molecular Mechanisms

Cadmium (Cd) is one of the most toxic metals in the environment, and has noxious effects on plant growth and production. Cd-accumulating plants showed reduced growth and productivity. Therefore, remediation of this non-essential and toxic pollutant is a prerequisite. Plant-based phytoremediation methodology is considered as one a secure, environmentally friendly, and cost-effective approach for toxic metal remediation. Phytoremediating plants transport and accumulate Cd inside their roots, shoots, leaves, and vacuoles. Phytoremediation of Cd-contaminated sites through hyperaccumulator plants proves a ground-breaking and profitable choice to combat the contaminants. Moreover, the efficiency of Cd phytoremediation and Cd bioavailability can be improved by using plant growth-promoting bacteria (PGPB). Emerging modern molecular technologies have augmented our insight into the metabolic processes involved in Cd tolerance in regular cultivated crops and hyperaccumulator plants. Plants’ development via genetic engineering tools, like enhanced metal uptake, metal transport, Cd accumulation, and the overall Cd tolerance, unlocks new directions for phytoremediation. In this review, we outline the physiological, biochemical, and molecular mechanisms involved in Cd phytoremediation. Further, a focus on the potential of omics and genetic engineering strategies has been documented for the efficient remediation of a Cd-contaminated environment