Search results for " mixtures"
showing 10 items of 885 documents
Micelles in Mixtures of Sodium Dodecyl Sulfate and a Bolaform Surfactant
2006
Mixtures composed of water, sodium dodecyl sulfate (SDS), and a bolaform surfactant with two aza-crown ethers as polar headgroups (termed Bola C-16) were investigated by modulating the mole ratios between the components. The two surfactants have ionic and nonionic, but ionizable, headgroups, respectively. The ionization is due to the complexation of alkali ions by the aza-crown ether unit(s). Structural, thermodynamic, and transport properties of the above mixtures were investigated. Results from surface tension, translational self-diffusion, and small angle neutron scattering ( SANS) are reported and discussed. Interactions between the two surfactants to form mixed micelles result in a com…
Selective hemicellulose hydrolysis of Scots pine sawdust
2019
The depletion of fossil resources is driving forward the search for new and alternative renewable feedstocks in the production of renewable chemicals, which could replace the petroleum-based ones. One such feedstock is pine (Pinus sylvestris) sawdust, which is generated enormous amounts in Finnish sawmills yearly. However, prior to the utilization in high-value applications, it needs to be fractionated into its constituents. In this work, the objective was to produce monomeric hemicellulose sugars from pine sawdust without degrading cellulose or lignin simultaneously. The influence of the reaction temperature and time, as well as acid type and concentration, was studied. Based on the result…
Comparison of oxidoreductive enzyme activities in three coal tar creosote-contaminated soils
2019
This study used laboratory experiments to compare the effects of coal tar creosote on the activity of oxidoreductive enzymes in sandy loam, loamy sand and sandy clay loam soils. Different amounts of coal tar creosote were added to soil samples as follows: 0 (control), 2, 10 or 50 g kg–1 dry matter. The activity of soil dehydrogenases (DHAs), o-diphenol oxidase (o-DPO), catalase (CAT), nitrate reductase (NR) and peroxidases (POX) was determined. Contamination of soil with coal tar creosote affected oxidoreductase activity. Oxidoreductive enzyme activity following soil contamination with coal tar creosote was in the following order: DHAs > CAT > NR > POX > o-DPO in…
Prenatal air pollution exposure and growth and cardio-metabolic risk in preschoolers
2020
Objectives: We investigated the association between outdoor air pollutants exposure in the first trimester of pregnancy, and growth and cardio-metabolic risk at four years of age, and evaluated the mediating role of birth weight. Methods: We included mother-child pairs (N = 1,724) from the Spanish INMA birth cohort established in 2003-2008. First trimester of pregnancy nitrogen dioxide (NO2) and fine particles (PM2.5) exposure levels were estimated. Height, weight, waist circumference, blood pressure, and lipids were measured at four years of age. Body mass index (BMI) trajectories from birth to four years were identified. Results: Increased PM2.5 exposure in the first trimester of pregnanc…
Additional file 1 of Cellular response to spinal cord injury in regenerative and non-regenerative stages in Xenopus laevis
2021
Additional file 1: Figure S1. Cellular response to spinal cord injury in R- and NR-stages. (A) Centriolar satellite ultrastructure (arrowheads) in cells surrounding the rostral stump. (B) Radial projection of cells lining the central canal (yellow shadow). (C) Neutrophil in the injury site at 2 dpt in animals at NF stage 50. (C-E) Cells lining a rosette structure at 6 dpt are characterized by a (D) basal collagen lamina (blue shadow), (E) interdigitations and adherent junctions (arrowheads), and (F) intermediate filaments (arrowheads). Graphs of the number of red blood cells/μm2 × 105 at (G) 2 and 6 dpt in NF stage 50, and (H) at 2 and 6 dpt in NF stage 66. Graphs of the number of macrophag…
Combustion behavior of black liquors : droplet swelling and influence of liquor composition
2017
The combustion of black liquor (BL) in a recovery boiler is a central process in a kraft pulp mill for recovering the cooking chemicals and for producing heat and power. This work explored the most important combustion behavior of BL, the swelling of in-flight droplets, from the viewpoint of liquor composition. It also studied the combustion behavior of BL droplets obtained from two biorefining subprocesses (carbonation and hot-water pretreatment, HWP) and sulfur-free pulping alternatives (soda-anthraquinone (AQ) and oxygen-alkali pulping). The formation of a plastic state essential for the swelling of BL droplet was found to result from the melting of an array of carbohydrate-derived aliph…
Priming effect increases with depth in a boreal forest soil
2016
Abstract Climate warming increases labile carbon (C) inputs to soil through increased photosynthesis and C allocation belowground. This could counterintuitively lead to losses of soil C via priming effects (PE): the stimulation of soil organic matter (SOM) decomposition caused by labile C addition. Systematic quantification of PEs in different ecosystems is needed. We measured PEs of free-living soil microbes in different layers of a boreal forest soil, and found that the relative magnitude of the PE increased with soil depth. The relationship between relative PE and the added glucose amount also depended on the soil layer. Our results indicate that the decomposition of SOM in deeper soil l…
“Anything taking shape?” : Capturing various layers of small group collaborative problem solving in an experiential geometry course in initial teache…
2022
Collaborative problem solving (CPS) is widely recognized as a prominent 21st-century skill to be mastered. Until recently, research on CPS has often focused on problem solution by the individual; the interest in investigating how the theorized problem-solving constructs function as broader social units, such as pairs or small groups, is relatively recent. Capturing the complexity of CPS processes in group-level interaction is challenging. Therefore, a method of analysis capturing various layers of CPS was developed that aimed for a deeper understanding of CPS as a small-group enactment. In the study, small groups of teacher education students worked on two variations of open-ended CPS tasks…
DEPS-testin luotettavuus ja pätevyys aikuisilla selkäpotilailla
2017
The Depression Scale (DEPS) is a patient-reported outcome instrument developed to recognize depressive symptoms. This study measured the psychometric properties of the DEPS among patients with degenerative spinal disease. Altogether 637 patients were included in the analysis. Main research question was whether the DEPS would meet pertinent psychometric criteria for reliability and validity. The results of analyses supported the DEPS instrument as a reliable and valid test to measure depressive symptoms among adult patients with spinal disease fulfilling the psychometric criteria. nonPeerReviewed
Aerosolization Performance of Jet Nebulizers and Biopharmaceutical Aspects
2019
In this work, 13 jet nebulizers, some of which in different configurations, were investigated in order to identify the biopharmaceutical constraints related to the quality attributes of the medicinal products, which affect their safety, efficiency, compliance, and effectiveness. The aerosolization parameters, including the aerosol output, aerosol output rate, mass median aerodynamic diameter, and fine particle fraction, were determined according to the European Standard EN 13544-1, using sodium fluoride as a reference formulation. A comparison between the aerosol output nebulization time and the fine particle fraction displayed a correlation between the aerosol quality and the nebulization …