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Personalgruppens psykologi

Personalgruppens psykologi ger en grundläggande översikt över de psykologiska processer som kännetecknar en personalgrupp. Enkelt och lättillgängligt presenterar författarna teorier och begrepp som kan fungera som redskap för att förstå arbetslagets och samarbetets psykologiska villkor. Teori varvas med praktiska övningar och resonemang kring hur samarbetsproblem och konflikter kan förebyggas och

ON KANNAN-GERAGHTY MAPS AS AN EXTENSION OF KANNAN MAPS

Extending the concept of weakly Kannan maps on metric spaces, we study the maps as $f:X\rightarrow X$ on a metric space $(X, d)$ satisfying condition $d(f(x), f(y)) \leq (1/2)\beta(d(x, y))[d(x ,f(x)) + d(y, f(y))]$ for every $x, y\in X$ and a function $\beta: [0, \infty)\rightarrow [0,1)$ where for every sequence $t=\{t_n\}$ of non-negative real numbers satisfying $\beta(t_n)\rightarrow 1,$ while

Self-reported quality of life before, during, and after pregnancy in women with CHD

Background:Adults with CHD are a growing patient group and childbirth is a relatively new phenomenon. EQ-5D is commonly used to measure health-related quality of life. We sought to investigate EQ-5D status before, during, and after pregnancy in women with CHD.Methods:We identified 128 pregnancies in 86 CHD women giving birth in Skåne County during 2009–2021. Repeated measures ANOVA was performed t

Layer-by-layer deposition of open-pore mesoporous TiO 2- Nafion® film electrodes

The formation of variable thickness TiO 2 nanoparticle- Nafion® composite films with open pores is demonstrated via a layer-by-layer deposition process. Films of about 6 nm diameter TiO 2 nanoparticles grow in the presence of Nafion® by "clustering" of nanoparticles into bigger aggregates, and the resulting hierarchical structure thickens with about 25 nm per deposition cycle. Film growth is chara

Growth-collapse mechanism of PEI-CTAB films at the air-water interface

We reveal a growth-collapse mechanism for self-assembled films of polyethyleneimine (PEI) and cetyltrimethylammonium bromide (CTAB) at the air-water interface. The work involved the quantification of film thickness on the micron scale through tracking oscillations in the amplitude and phase angles using single-angle, single-wavelength ellipsometry. Our results allow us to propose the following int

Incorporation of sparingly soluble species in mesostructured surfactant-polymer films

Recently we have investigated the formation of novel thick, solid, mesostructured films of polymer/surfactant mixtures which form spontaneously at the air-solution interface. Here we report studies of the effect of adding a series of sparingly soluble species to the precursor solution, to alter the mesostructure of cetyltrimethylammonium bromide/polyethylenimine films and to investigate the incorp

Further Improvements in the Long-Range Order of MCM-41 Materials

Synthetic methods for making an all-silica MCM-41 mesoporous silicate of high long-range order are reported. The product shows up to seven orders of X-ray diffraction and good stability under calcination conditions. The greatest improvement in structure occurs when the pH is held between 9 and 10 during synthesis and the sulfate anion is present.

Current understanding of formation mechanisms in surfactant-templated materials

Surfactant-templated materials are created through self-assembly in solutions containing both surfactant micelles and an inorganic species. The resulting materials are composites containing an organized surfactant micelle array encapsulated in the inorganic material. Removal of the surfactants generates nanoscale pores which replicate the highly organized micelle phase, producing high surface area

Probing hysteresis during sorption of cyclohexane within mesoporous silica using NMR cryoporometry and relaxometry

The conventional data analysis methods for obtaining a pore size distribution (PSD) from gas sorption data make several critical assumptions that impact significantly on the accuracy of the PSD thereby obtained. In particular, assumptions must be made concerning the nature of the pore-filling or emptying process in adsorption, or desorption, respectively. The possibility of pore-pore interactions

Electro-deposition of thin cellulose films at boron-doped diamond substrates

Cellulose films of variable thickness are electro-deposited from aqueous alkaline thiourea solution onto polished boron-doped diamond substrates in an anodic process. Films with "net-like" topography are formed and shown to consist of both cellulose-I and cellulose-II components. Properties of these films are investigated. When immersed in aqueous electrolyte solution, ion partitioning into the el

Association of titania with nonionic block copolymers in ethanol : The early stages of templating and film formation

We have prepared self-supporting, free-standing titania-surfactant mesostructured films via spontaneous growth on the surface of ethanolic solutions, as an alternative synthetic route to evaporation induced self-assembly. The initial stages of surfactant templating and interfacial film formation in alcoholic solutions of titania with a polyethylene-poly(ethylene glycol) surfactant have been observ

Interactions and film formation in polyethylenimine-cetyltrimethylammonium bromide aqueous mixtures at low surfactant concentration

The interactions involved in aqueous mixtures of polyethyleneimine (PEI) and cetyltrimethylammonium bromide (CTAB) were studied under dilute conditions. The phase diagram of this polyelectrolyte-surfactant system of similar charge was constructed by determining the CAC and CMC* values at different PEI concentrations, using surface-tension and conductivity measurements, respectively. Formation of t

Nanoscum : Solid nanostructured films at the air-water interface

The formation of solid films at the air-solution interface is a common phenomenon, however, these films have largely not been explored from a materials point of view. In solutions containing inorganic species with surfactants these films, which can be several microns thick, have a highly organised nanoscale structure aligned with respect to the interface. More recently similar polyelectrolyte-surf

Robust ordered cubic mesostructured polymer/silica composite films grown at the air/water interface

Polymer/silica composite films, stable to calcination, were produced using catanionic surfactant mixtures (hexadecyltrimethylammonium bromide (CTAB) and sodium dodecyl sulfate (SDS)) and polymers (polyethylenimine (PEI) or polyacrylamide (PAAm)) at the air/water interface. Film formation processes were probed by time-resolved neutron reflectivity measurements. Grazing incidence X-ray diffraction (

Evolution of non-ionic surfactant-templated silicate films at the air-liquid interface

Spontaneous growth of non-ionic surfactant-templated thin films at the air-water interface was investigated using three techniques: Brewster angle microscopy (BAM), time-resolved off-specular X-ray reflectivity and grazing incidence X-ray diffraction (GIXD). Experiments were also carried out to study the evolution of micelles in the subphase solution using small-angle neutron scattering (SANS). Fi

Atomistic structure of a micelle in solution determined by wide Q-range neutron diffraction

The accepted picture of the structure of a micelle in solution arises from the idea that the surfactant molecules self-assemble into a spherical aggregate, driven by the conflicting affinity of their head and tail groups with the solvent. It is also assumed that the micelles size and shape can be explained by simple arguments involving volumetric packing parameters and electrostatic interactions.

Silica gels with tunable nanopores through templating of the L3 phase

We describe a detailed synthesis of a silicified inorgaric/organic nanoporous monolithic composite conforming to the lyotropic liquid crystalline L3 phase. The pore dimensions of the silicified L3 phase scale with the solvent volume fraction in the synthesis reaction mixture. Changing the solvent fraction in the initial solution changes the ultimate pore diameter in the silicate, providing a simpl