A Probabilistic‐Statistical Model of Change of Particle Size Distribution in Settlers and Tanks

A probabilistic and statistical model of changes in the particle size distribution of the dispersed phase of low‐concentrated suspensions has been developed. The applicability of the method is theoretically substantiated. It is demonstrated that changes in the particle size distribution, in particular in the field of gravity, can be described by the Fokker‐Planck‐Kolmogorov equation.     

Desulfurization of Tall Oil Rosin

Tall oil rosin has limited application due to the presence of sulfur compounds. By treatments with acetic acid and 2‐ethoxyethanol the total sulfur content of tall oil rosin was reduced from 630 to 48 ppm.     

Lipid Emulsions Differentially Affect LPS-Induced Acute Monocytes Inflammation: In Vitro Effects on Membrane Remodeling and Cell Viability

The aim of this study was to assess how lipid emulsions for parenteral nutrition affect lipopolysaccharide (LPS)‐induced acute monocyte inflammation in vitro. An 18 h long LPS induced human monocyte leukemia cell stimulation was performed and the cell‐growth medium was supplemented with three different industrial lipid emulsions: Intralipid^®, containing long‐chain triglycerides (LCT—soybean oil); Medialipid^®, containing LCT (soybean oil) and medium‐chain triglycerides (MCT—coconut oil); and SMOFlipid^®, containing LCT, MCT, omega‐9 and ‐3 (soybean, coconut, olive and fish oils). Cell viability and apoptosis were assessed by Trypan blue exclusion and flow cytometry respectively. Monocyte composition and membrane remodeling were studied using gas chromatography and NR12S staining. Microparticles released in supernatant were measured by prothrombinase assay. After LPS challenge, both cellular necrosis and apoptosis were increased (threefold and twofold respectively) and microparticle release was enhanced (sevenfold) after supplementation with Medialipid^® compared to Intralipid^®, SMOFlipid^® and monocytes in the standard medium. The monocytes differentially incorporated fatty acids after lipid emulsion challenge. Finally, lipid‐treated cells displayed microparticles characterized by disrupted membrane lipid order, reflecting lipid remodeling of the parental cell plasma membrane. Our data suggest that lipid emulsions differentially alter cell viability, monocyte composition and thereby microparticle release. While MCT have deleterious effects, we have shown that parenteral nutrition emulsion containing LCT or LCT and MCT associated to n‐3 and n‐9 fatty acids have no effect on endotoxin‐induced cell death and inflammation.     

Improvement of sound absorption and flexural compliance of porous alumina-mullite ceramics by engineering the microstructure and segmentation into topologically interlocked blocks

Ceramic plates composed of topologically interlocked osteomorphic blocks with mono- and bimodal pore size distributions are fabricated by combining freeze gelation and sacrificial templating and trialled for sound absorption. These blocks present a concavo-convex geometry that constrains their movement solely by the contact with the neighbors. Our studies show that by using porous osteomorphic blocks, enhanced sound absorption coefficient (α) of 0.97 at 420 Hz can be reached, indicating that the gaps between blocks have a significant effect on the sound absorption at frequencies lower than 600 Hz, whereas the bimodal porosity of the block material enhances sound absorption for higher frequencies. Indentation tests confirm the advantages of the topologically interlocked structures, such as a spectacularly high flexural compliance, as compared to monolithic parts made from the same material. We concluded that materials design based on topological interlocking leads to an excellent combination of mechanical and sound absorption properties.     

Impact of Cold Ischemia on Mitochondrial Function in Porcine Hearts and Blood Vessels

The effects of cold storage using Custodiol^® (Histidine-Tryptophan-Ketoglutarate, HTK) or isotonic saline solution on mitochondrial function in hearts (left and rights ventricles) and various blood vessels of pigs were investigated. Hearts, saphenous veins, internal-mammary-arteries and aortas of male landrace pigs were harvested and exposed to cold ischemia in either saline or Custodiol-HTK solution. Mitochondrial function was measured in situ in permeabilized fibers by high-resolution respirometry. Mitochondrial respiratory capacities (maximal respiration rates) were similar in the right and left ventricle in controls and after 14 h of cold storage were significantly better preserved in Custodiol-HTK than in saline solution. Mitochondrial respiration rates in various blood vessels including aorta, arteries and veins were less than 5% of myocardium rates. In contrast to the pig heart, in some blood vessels, like veins, mitochondrial function remained stable even after 24 h of cold ischemia. HTK-Custodiol protection of mitochondrial function after prolonged cold ischemia was observed in the myocardium but not in blood vessels. HTK-Custodiol solution thus offers significant protection of myocardial mitochondria against cold ischemic injury and can be used as efficient preservation solution in organ transplantation but probably has no benefit for blood vessels preservation. Analysis of mitochondrial function can be used as a valuable approach for the assessment of cold ischemic injury in various tissues including pig heart and various blood vessels.     

Determining Aerosol Volatility Parameters Using a “Dual Thermodenuder” System: Application to Laboratory-Generated Organic Aerosols

Thermodenuders (TD) are a tool widely used for measuring aerosol volatility in the laboratory and field. Extracting the parameters that dictate organic aerosol volatility from TD data is challenging because gas-particle partitioning rarely reaches equilibrium inside a TD operating under atmospheric conditions, thus a wide variety of parameter sets can explain observed evaporation. Component volatilities (as represented by saturation vapor pressure, C_sat), cannot be directly extracted due to uncertainties in potential limitations to mass transfer (represented by mass accommodation coefficient, α) and components’ enthalpies of evaporation (ΔH_vap). To address these limitations, we have developed a “dual TD” experimental approach in which one line uses a temperature-stepping TD (TS-TD) with a relatively long residence time (RT) and the other operates isothermally at variable residence time (VRT-TD). Data from this approach are used in tandem with an optimizing evaporation kinetics model to extract the values of parameters dictating volatility (C_sat, and associated values of ΔH_vap and α). The system was evaluated using laboratory generated dicarboxylic acid aerosols (adipic acid and succinic acid). Excellent agreement with previously published evaporation data collected with other TD systems was observed. Parameter values reported in the literature for the tested acids vary widely, but our results are generally consistent with those from studies that allow for nonunity values of α. For example, our results suggest that α for these aerosols are of order 0.1, in agreement with results determined by Saleh et al. (2009, 2012). Modeling results suggest that the addition of VRT-TD data provides tighter constraint on feasible ΔH_vap and α values. The dual TD approach presented here does not rely on equilibration in the TD and thus can be directly applied to extract volatility parameters for more complex laboratory and ambient organic aerosol systems.

Copyright 2015 American Association for Aerosol Research     

Theory of chromatography of ring-shaped block copolymers

A theory is developed for describing liquid chromatography of ring diblock and multiblock copolymers. The chromatographic behavior of ring block copolymers at different adsorption interactions is analyzed theoretically and compared with that of linear block copolymers; typical chromatograms are simulated by using the theory. In particular, it is shown that under the critical interaction condition for one block the chromatographic retention of a ring diblock copolymer is dependent of the length of the ‘critical’ block; this behavior differs qualitatively from that of a linear diblock copolymer. Ring copolymers are always more retained than linear ones, therefore such copolymers can be separated. Especially good separation of heterogeneous ring and linear block copolymers is predicted at near-critical interaction conditions. According to the theory, ring diblocks and multiblocks can be separated as well, if one component of a copolymer is adsorbing, while the other one is not adsorbing.     

Physicochemical and optical properties of glasses in the Ga<Subscript>4</Subscript>Ge<Subscript>21</Subscript>Se<Subscript>50</Subscript>-Sb<Subscript>2</Subscript>Se<Subscript>3</Subscript> system

This paper reports on the results of an investigation into the concentration behavior of the glass-forming ability, heat resistance, glass transition temperature, density, refractive index, transparent spectral region, and impurity optical absorption of glasses in the Ga₄Ge₂₁Se₅₀-Sb₂Se₃ system. The data obtained indicate that glasses in the Ga₄Ge₂₁Se₅₀-Sb₂Se₃ system with a high Sb₂Se₃ content are of interest as materials for use in fiber optics.     

Multiple anion···π interactions with a soft selenium atom: Accommodation of NCSe anions inside hydrophobic pockets of adamantane/1,2,4-triazole coordination framework

A new framework coordination polymer {[Cd₃(tr₂ad)₆](NCSe)₆·12H₂O}_n [tr₂ad-4,4′-(adamantane-1,3-diyl)bis(1,2,4-triazole)] exhibits 3D primitive cubic topology adopted by trinuclear [Cd₃(tr)₁₂] net nodes and tridentate tr₂ad links. The structure reveals unprecedented multiple anion ···π interactions employing the soft Se site of the ambifunctional NCSe^? anion and three triazole groups pre-arranged on a tricadmium matrix. The framework generates hydrophobic pockets serving for hosting the uncoordinated anions by a concerted action of Se···π and CH···Se interactions.     

Composition and properties of complexes between anionic liposomes and diblock copolymers with cationic and poly(ethylene oxide) blocks

A series of cationic diblock copolymers were synthesized via sequential anionic polymerization of 2‐vinylpyridine and ethylene oxide and further quaternization of the resulting diblock copolymers with dimethyl sulfate. Diblock copolymers with a degree of polymerization (DP) of the cationic block equal to 40 and DP of the poly(ethylene oxide) (PEO) block equal to 45, 210 and 450, as well as a cationic homopolymer with DP = 40 (control), were adsorbed on the surface of anionic liposomes of 40–60 nm in diameter. The liposomes were constructed with egg lecithin admixed with 0.1 mole fraction of a doubly anionic lipid, cardiolipin. The liposome–polymer complexes were characterized using electrophoretic mobility measurements, dynamic light scattering, conductivity, fluorescence and UV spectroscopy, and differential scanning calorimetry. Adsorption of the polymers causes the liposomes to aggregate; the only exception is the diblock copolymer with DP of the PEO block of 450, which shows an aggregation‐preventing effect. In all cases, the integrity of liposomes is retained upon their complexation with polymers. The diblock copolymer with a short PEO block induces clustering of anionic lipid in the outer leaflet of the membrane; this effect becomes less pronounced with increasing DP of the PEO block. The differences in behaviour of the diblock copolymers are explained in terms of copolymer cluster formation via hydrogen bonding between neighbouring PEO blocks. These observations are important for interpretation of biological effects produced by cationic polymers and selection of cationic polymers for biomedical applications. © 2017 Society of Chemical Industry