Pickering emulsions with a remarkable transmittance of up to 86% across the visible spectrum have been prepared without adjusting the refractive index (RI) of the stabilizing particles to those of ...the aqueous and oil phases. Commercially available hydrophilic silica particles with a diameter of 20 nm, which are hydrophobized partially in situ, were used to stabilize water droplets with diameters below 400 nm in IsoparM. In this system, the stabilizing particles and the emulsion droplets act as one single scattering object, which renders RI-matching of the particles unnecessary. By either evaporation of some water from the droplets or addition of an appropriate organic liquid to the oil phase, it is possible to match the RI of the droplets (aqueous phase + particles) with that of the continuous phase, which minimizes scattering and results in highly transparent emulsions.
Understanding the infrared (IR) spectral response of materials as a function of their morphology is not only of fundamental importance but also of contemporary practical need in the analysis of ...biological and synthetic materials. While significant work has recently been reported in understanding the spectra of particles with well-defined geometries, we report here on samples that consist of collections of particles. First, we theoretically model the importance of multiple scattering effects and computationally predict the impact of local particles’ environment on the recorded IR spectra. Both monodisperse and polydisperse particles are considered in clusters with various degrees of packing. We show that recorded spectra are highly dependent on the cluster morphology and size of particles but the origin of this dependence is largely due to the scattering that depends on morphology and not absorbance that largely depends on the volume of material. The effect of polydispersity is to reduce the fine scattering features in the spectrum, resulting in a closer resemblance to bulk spectra. Fourier transform-IR (FT-IR) spectra of clusters of electromagnetically coupled poly(methyl methacrylate) (PMMA) spheres with wavelength-scale diameters were recorded and compared to simulated results. Measured spectra agreed well with those predicted. Of note, when PMMA spheres occupy a volume greater than 18% of the focal volume, the recorded IR spectrum becomes almost independent of the cluster’s morphological changes. This threshold, where absorbance starts to dominate the signal, exactly matches the percolation threshold for hard spheres and quantifies the transition between the single particle and bulk behavior. Our finding enables an understanding of the spectral response of structured samples and points to appropriate models for recovering accurate chemical information from in IR microspectroscopy data.
Gegenstand dieser Open Access Publikation sind die Auswirkungen automatisierter und vernetzter Fahrzeuge auf die Europäische Stadt sowie die Voraussetzungen, unter denen diese Technologie einen ...positiven Beitrag zur Stadtentwicklung leisten kann. Dabei vertreten die Autorinnen und Autoren zwei Thesen, die im wissenschaftlichen Diskurs bislang wenig Beachtung fanden: Automatisierte und vernetzte Fahrzeuge werden sich für lange Zeit nicht in allen Teilräumen der Stadt durchsetzen. Dies hat zur Folge, dass bislang angenommene Wirkungen - von der Verkehrssicherheit bis zur Verkehrsleistung sowie räumliche Effekte - neu bewertet werden müssen. Um einen positiven Beitrag dieser Technologie zur Mobilität der Zukunft sicherzustellen, müssen verkehrs- und siedlungspolitische Regulationen weiterentwickelt werden. Etablierte territoriale, institutionelle und organisatorische Grenzen sind zeitnah zu hinterfragen. Trotz oder wegen der bestehenden großen Unsicherheiten befinden wir uns am Beginn einer Phase des Gestaltens - in der Technologieentwicklung, aber eben auch in der Politik, Stadtplanung, Verwaltung und der Zivilgesellschaft. Die Autorinnen und Autoren Ein interdisziplinäres Team an der Fakultät für Architektur und Raumplanung der TU Wien hat die vorliegenden Forschungsergebnisse gemeinsam erarbeitet. Das Projekt wurde als Ladenburger Kolleg von der Daimler und Benz Stiftung gefördert.
AR-TO-KID is an application produced for preschool children between ages five to six years old with an Augmented Reality (AR) application. The significant purpose of AR-TO-KID is to improve the ...pronunciation of the children in English. Hence, this paper discusses an AR application with speech input. The detection of the children speech input when they need to pronounce the words correctly, and they need to have critical thinking to identify the environment suit with the 3D objects that they will utter the word. Educational technology should be interactive and attractive for 5 to 6 years old preschool children learning; however, some at preschool teachers still used the conventional methods in teaching and children are not fully engaged with the method. Therefore, this project is to design and develop an interactive AR tool called AR-TO-KID for preschool children in pronunciation learning and teaching. This paper presents the evaluation and testing for preschool children with non-native English speaking. The article ends with results and discussion.
Long-term performance and fouling behavior of four full-scale nanofiltration (NF) plants, treating anoxic groundwater at 80% recovery for drinking water production, were characterized and compared ...with oxic NF and reverse osmosis systems. Plant operating times varied between 6 and 10 years and pretreatment was limited to 10µm pore size cartridge filtration and antiscalant dosage (2–2.5mgL−1) only. Membrane performance parameters normalized pressure drop (NPD), normalized specific water permeability (Kw) and salt retention generally were found stable over extended periods of operation (>6 months). Standard acid–base cleanings (once per year or less) were found to be sufficient to maintain satisfying operation during direct NF of the described iron rich (≤8.4mgL−1) anoxic groundwaters.
Extensive autopsies of eight NF membrane elements, which had been in service since the plant startup (6–10 years), were performed to characterize and quantify the material accumulated in the membrane elements. Investigations using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), total organic carbon (TOC) and adenosine triphosphate (ATP) measurements revealed a complex mixture of organic, biological and inorganic materials. The fouling layers that developed during half to one year of operation without chemical cleaning were very thin (<2µm). Most bio(organic) accumulates were found in the lead elements of the installations while inorganic precipitates/deposits (aluminosilicates and iron(II)sulfides) were found in all autopsied membrane elements.
The high solubility of reduced metal ions and the very slow biofilm development under anoxic conditions prevented rapid fouling during direct NF of the studied groundwaters. When compared to oxic NF and RO systems in general (e.g. aerated ground waters or surface waters), the operation and performance of the described anoxic installations (with minimal pretreatment) can be described as very stable.
•Anoxic feed water enables stable long term NF performance at 4 full-scale plants.•Anoxic conditions prevent rapid iron and biological fouling.•Direct NF: 10μm cartridge filtration and antiscalant dosage only.•Cleaning once per year is sufficient to maintain stable NF performance.•Slow performance decline by composite fouling (biological and (in)organic).
Stressed by complex internal flows, fish has a special locomotion feature different from the cruise in a jet fish pump. Based on the high-speed photography and dynamic mesh technologies, the present ...paper proposed a new numerical simulation methodology to study the impact of fish locomotion on the internal flow in a jet fish pump. The results show that both single fish and fish shoal can cause wall static pressure peaks. Fish causes a rise of static pressure around its body and the pressure increment increases as primary flow rate grows. Fish shoal can result in a decrease of the measured value of mixed flow rate, yet the locomotion of single fish shows no significant effect on it. As the rise of axial velocity difference between internal flow and fish, a low axial velocity region closed to fish body downstream expands. Fish locomotion has a significant effect on the recirculation region. The recirculation region firstly breaks and then forms again when fish passes through this region. The investigation results are helpful to understand the change of flow field in jet fish pumps disturbed by fish and provide reference for design and optimization of jet fish pumps. This new methodology also provides a solution for simulating of moving object in flow fields.
•A new numerical simulation methodology is proposed to study fish locomotion in a jet fish pump.•Effects of fish locomotion on the pressure distribution are discussed in a jet fish pump.•Impacts of fish shoal transportation on measured values of flow rates are analyzed.
Contamination by fungi and bacteria during the in vitro propagation of plants leads to considerable losses of biological material and precludes phytosanitary certification. The anti-microbial effect ...of silver nanoparticles (AgNPs) may be an alternative for the eradication of in vitro contaminants. This study evaluated the microbicidal activity of AgNPs on a recurrent fungus during the micropropagation of stevia (
Stevia rebaudiana
Bertoni). First, the fungus was isolated and identified at a molecular level by the sequencing and analysis of the ITS4/ITS5 rDNA region
.
The results of the phylogenetic analysis of various fungal species showed that the strain under study (16-166-H) belongs to the genus
Sordaria
and is 99.64% similar to
S. tomento-alba
(strain CBS 260.78). Subsequently, the inhibition of the growth of
S. tomento-alba
was tested under different concentrations of AgNPs (0, 25, 50, 100, and 200 mg L
−1
), observing that 50 and 100 mg L
−1
achieve ca. 50% growth inhibition (IC
50
), while 200 mg L
−1
produces a drastic inhibition. On the other hand, the shape and size of AgNPs was examined using transmission electron microscopy (TEM), and the transport and accumulation of AgNPs in
S. tomento-alba
cells were monitored through multiphoton microscopy. The morphological and fluorescence analyses showed that AgNPs display different sizes, with larger nanoparticles retained in fungal cell walls while smaller AgNPs penetrate into fungal cells. Probably, apoplastic and symplastic mechanisms involved in the accumulation and transport of AgNPs affect the metabolic processes of the fungus, thus inhibiting its growth. These results suggest that AgNPs possess antifungal activity and can be used in the eradication of contaminants during the in vitro culture of plant species.
Key message
The microbicidal potential of AgNPs in the micropropagation of different plant species.
Conventional two-dimensional as well as established three-dimensional cell culture systems exhibit a high modulus of elasticity, which largely do not represent the stiffness of human organs. This ...chapter describes a protocol to establish 3D cell cultures of human adipose tissue-derived mesenchymal stromal cells (hAT-MSC) on low stiffness silicon scaffolds. These feature a defined growing environment with a stiffness close to physiology, thus being useful for in vitro investigations for multiple applications.
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