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2021 ◽  
Author(s):  
Henrik Rosenkvist

Abstract While the Swedish negator inte may be doubled in a final clause-external position, in both standard Swedish and dialects, many dialects also allow a final, clause-internal particle (e, i or ai) in negated clauses. FNPs occur in a coherent area around the Baltic Sea, and in contrast with doubling negation, they are possible both after both inte and aldrig ‘never’. FNPs are also used in questions and exclamations, contexts that disallow doubling negation. These particles may have developed from the former Swedish negator ej or from the common inte. An argument for the former alternative is that other dialectal phenomena that spread from central Sweden during the late Middle Ages have approximately the same geographic distribution. In the final section of the paper, some typological consequences and implications are discussed. Furthermore, it is argued that syntactic studies of non-standard varieties may reveal new insights of typological relevance.


Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3648
Author(s):  
Jiali Zhai ◽  
Bo Fan ◽  
San H. Thang ◽  
Calum J. Drummond

Non-lamellar lyotropic liquid crystalline (LLC) lipid nanoparticles contain internal multidimensional nanostructures such as the inverse bicontinuous cubic and the inverse hexagonal mesophases, which can respond to external stimuli and have the potential of controlling drug release. To date, the internal LLC mesophase responsiveness of these lipid nanoparticles is largely achieved by adding ionizable small molecules to the parent lipid such as monoolein (MO), the mixture of which is then dispersed into nanoparticle suspensions by commercially available poly(ethylene oxide)–poly(propylene oxide) block copolymers. In this study, the Reversible Addition-Fragmentation chain Transfer (RAFT) technique was used to synthesize a series of novel amphiphilic block copolymers (ABCs) containing a hydrophilic poly(ethylene glycol) (PEG) block, a hydrophobic block and one or two responsive blocks, i.e., poly(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyl acrylate) (PTBA) and/or poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA). High throughput small angle X-ray scattering studies demonstrated that the synthesized ABCs could simultaneously stabilize a range of LLC MO nanoparticles (vesicles, cubosomes, hexosomes, inverse micelles) and provide internal particle nanostructure responsiveness to changes of hydrogen peroxide (H2O2) concentrations, pH and temperature. It was found that the novel functional ABCs can substitute for the commercial polymer stabilizer and the ionizable additive in the formation of next generation non-lamellar lipid nanoparticles. These novel formulations have the potential to control drug release in the tumor microenvironment with endogenous H2O2 and acidic pH conditions.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Blaž Tropenauer ◽  
Dušan Klinar ◽  
Janvit Golob

Abstract Spent Pot Lining (SPL) cathode pot, waste from the aluminium smelting process needs detoxification from cyanides, washing out water-soluble salts and extraction of the cryolite (Na3AlF6) decomposition products to be recycled. Revealed cryolite decomposition mechanism with NaOH opens possibilities to explore its critical role in the reactive extraction process. Common Na+ ion from NaOH hinders the solubility of the product but also drives mass transfer to the reaction site. Reaction mass balance provides adequate liquid to solid ratio (L/S) and NaOH concentration range. A newly developed kinetic model based on Whitman film theory and NaOH mass flow enables prediction of the reaction time to decompose cryolite to a low enough level. Results show that the internal particle resistance to transport (1/ks) is 19 times larger than the external (1/kl) one and governs the whole process.


2021 ◽  
Author(s):  
Anne Pluymakers ◽  
Auke Barnhoorn ◽  
Richard Bakker

<p>Not all rocks are perfect. Frequently heterogeneities will be present, either in the form of pre-existing fractures, or in the form of sealed fractures. To date, investigation of sample heterogeneity, specifically tensile strength and strength anisotropy has focused on layered rocks, such as shales, sandstones and gneisses. Data is lacking on the effect of single planar heterogeneities, such as pre-existing fractures or stylolites, even though these frequently occur in geo-energy settings.</p><p>We have performed Brazilian Disc tests on limestone samples containing planar heterogeneities, investigating Brazilian test Strength (BtS) and the effects of orientation on strength. We used prefractured Indiana limestone to represent a planar heterogeneity without cohesion and Treuchtlinger Marmor samples with central stylolites to represent a planar heterogeneity of unknown strength (as an example of a sealed fracture). The planar discontinuity was set at different rotation angles of approximately 0–20–30–45–60–90⁰, where 90⁰ (steep angle) is parallel to the principal loading direction, and 0⁰ (low angle) to the horizontal axis of the sample. All experiments were filmed, and where possible Particle Image Velocimetry was used to determine internal particle motion. Moreover, we used a 2D Comsol model in which we simplified the stylolite surface as a sinusoid. The model was used to qualitatively determine how i) a different period of the sinusoid and ii) relative strength of sinusoid/matrix affect the results.</p><p>Our results show that all imperfect samples are weaker than intact samples. The 2D Comsol model indicates that the qualitative results remain unaffected by changing the period (assumed to be representative of roughness) of the cohesive heterogeneity, nor by the relative strength contrast: the location of the first fracture remains unaffected. For both heterogeneity types, the fracture patterns can be divided into four categories, with two clear endmembers, and a more diffusive subdivision in between.</p><p>For a cohesion-less heterogeneity:</p><ul><li>steep angles lead to frictional sliding along the interface, and only a small hypothesized permeability increase.</li> <li>Intermediate angles lead to a combination of tensile failure of the matrix and sliding along the interface, where for steeper angles more new fractures form which follow the path of the existing fracture.</li> <li>Low angles lead to closure of the old fracture and new tensile failure.</li> </ul><p>For a cohesive heterogeneity of unknown cohesion:</p><ul><li>Steep angles lead to intensive failure of the heterogeneous zone, attributed to the presence of a stress concentrator.</li> <li>Intermediate angles lead to partial failure along the heterogeneous zone, and the formation of new fractures in the matrix, potentially instigated by mode II failure to accommodate motion.</li> <li>Low angles lead to the formation of a new fracture plus opening within the heterogeneous zone.</li> </ul><p>These results imply that hydrofracture (i.e. creating tensile stresses) of a stylolite-rich zone will lead to more fractures than fractures in a homogeneous zone, where the orientation of the stylolites and bedding will control the orientation of the permeable pathways.</p>


2020 ◽  
Vol 32 (1) ◽  
pp. 3-15
Author(s):  
M Schümann ◽  
D Yu Borin ◽  
J Morich ◽  
S Odenbach

Magnetorheological elastomers are a class of smart hybrid material where magnetic microparticles are embedded in an elastomer matrix. The combination of elastic and magnetic properties leads to highly complex material behaviour, which is strongly affected by the arrangement and the magnetically induced motion of the magnetic particles. Thus, the knowledge of the internal particle structure is key to gain a deeper understanding of the complex material behaviour. In this paper, X-ray microtomography was applied to analyse the internal particle structure of a magnetorheological elastomer containing magnetically hard NdFeB-particles. A stepwise magnetisation of the material enabled a detailed characterisation of the occurring non-reversible chain formation process. Furthermore, the application of magnetic fields during measurements enabled an analysis of a mostly reversible particle motion occurring in connection with the magnetorheological effect. The collected tomography data of the particle structure was evaluated on a single particle basis as well as by means of a direction-dependent pair correlation function. To provide a scale bridging between macroscopic and microscopic properties, the found results regarding the particle motion were linked to mechanical and magnetic properties of the material.


Author(s):  
Kota Fujiwara ◽  
Yuki Nakamura ◽  
Kohei Yoshida ◽  
Akiko Kaneko ◽  
Yutaka Abe

Abstract Nuclear power plant (NPP) safety has become a public issue since the Fukushima daiichi NPP accident. In order to evaluate the risks caused by severe accidents (SAs), it is very important to understand the on-site source term events. One of the important unsolved source term events is the decontamination efficiency of fission products (FPs) in the suppression chamber by pool scrubbing. Therefore, a mechanistic model to analyze the particle decontamination efficiency by pool scrubbing is highly regarded. Despite the demand, particle decontamination mechanism by pool scrubbing has never been understood due to the complexity of phenomena. In our experiment, we aim to develop a reliable mechanistic model to evaluate particle decontamination efficiency of pool scrubbing by conducting separate effect tests. As to obtain the fundamental process of particle decontamination from gas to liquid-phase, we focused on decontamination factor (DF) of particle from a single bubble. However, it is very difficult to calculate the initial particle concentration inside the bubble. Therefore, in our experiment, we developed a method to measure the internal particle concentration inside the bubble by combining image processing and particle measurement. By using the experimental results, we succeeded to obtain reasonable DF for glycerin particles and CsI particles as a simulant particle for FPs. From the experimental results, detailed particle decontamination efficiency for various submergence were measured. The results tend show that DF increase linearly as submergence increases which suggests that DF is constant on bubble rise region. Moreover, the fact that glycerin particle with larger particle diameter takes a higher value shows that particle diameter significantly affects DF.


2019 ◽  
Vol 10 ◽  
pp. 2594-2608 ◽  
Author(s):  
Arianna Gennari ◽  
Julio M Rios de la Rosa ◽  
Erwin Hohn ◽  
Maria Pelliccia ◽  
Enrique Lallana ◽  
...  

This study is about linking preparative processes of nanoparticles with the morphology of the nanoparticles and with their efficiency in delivering payloads intracellularly. The nanoparticles are composed of hyaluronic acid (HA) and chitosan; the former can address a nanoparticle to cell surface receptors such as CD44, the second allows both for entrapment of nucleic acids and for an endosomolytic activity that facilitates their liberation in the cytoplasm. Here, we have systematically compared nanoparticles prepared either A) through a two-step process based on intermediate (template) particles produced via ionotropic gelation of chitosan with triphosphate (TPP), which are then incubated with HA, or B) through direct polyelectrolyte complexation of chitosan and HA. Here we demonstrate that HA is capable to quantitatively replace TPP in the template process and significant aggregation takes place during the TPP–HA exchange. The templated chitosan/HA nanoparticles therefore have a mildly larger size (measured by dynamic light scattering alone or by field flow fractionation coupled to static or dynamic light scattering), and above all a higher aspect ratio (R g/R H) and a lower fractal dimension. We then compared the kinetics of uptake and the (antiluciferase) siRNA delivery performance in murine RAW 264.7 macrophages and in human HCT-116 colorectal tumor cells. The preparative method (and therefore the internal particle morphology) had little effect on the uptake kinetics and no statistically relevant influence on silencing (templated particles often showing a lower silencing). Cell-specific factors, on the contrary, overwhelmingly determined the efficacy of the carriers, with, e.g., those containing low-MW chitosan performing better in macrophages and those with high-MW chitosan in HCT-116.


2019 ◽  
Vol 59 (2) ◽  
pp. 905-918
Author(s):  
Weitong Pan ◽  
Xueli Chen ◽  
Gance Dai ◽  
Fuchen Wang

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