scholarly journals Acoustically Manipulating Internal Structure of Disk-in-Sphere Endoskeletal Droplets

2021 ◽  
Author(s):  
Gazendra Shakya ◽  
Tao Yang ◽  
Yu Gao ◽  
Apresio Fajrial ◽  
Baowen Li ◽  
...  
Keyword(s):  
Internal Structure ◽  
Directed Assembly ◽  
Nano Particles ◽  
Driving Frequency ◽  
Physical Mechanisms ◽  
On Demand ◽  
Intracellular Organelles ◽  
First Time ◽  
Complicated Nature ◽  
Internal Architecture

Abstract Manipulation of micro/nano particles has been well studied and demonstrated by optical, electromagnetic, and acoustic approaches, or their combinations. Manipulation of internal structure of droplet/particle is rarely explored and remains challenging due to its complicated nature. Here we demonstrated the manipulation of internal structure of disk-in-sphere endoskeletal droplets using acoustic wave for the first time. We developed a model to investigate the physical mechanisms behind this novel phenomenon. Theoretical analysis of the acoustic interactions indicated that these assembly dynamics arise from a balance of the primary and secondary radiation forces. Additionally, the disk orientation was found to change with acoustic driving frequency, which allowed on-demand, reversible adjusting disk orientations with respect to the substrate. This novel dynamic behavior leads to unique reversible arrangements of the endoskeletal droplets and their internal architecture, which may provide a new avenue for directed assembly of novel hierarchical colloidal architectures and intracellular organelles or intra-organoid structures.

scholarly journals An exceptionally preserved conulariid from Ordovician erratics of Northern European Lowlands

PalZ ◽  
2021 ◽  
Author(s):  
Consuelo Sendino ◽  
Martin M. Bochmann
Keyword(s):  
Internal Structure ◽  
Late Pleistocene ◽  
Point Of View ◽  
Three Dimensions ◽  
Northern European ◽  
Current Location ◽  
Transport Direction ◽  
First Time ◽  
Erratic Boulder

AbstractA conulariid preserved in three dimensions from Ordovician fluvioglacial erratics of the Northern European Lowlands (North German Plain) is described under open nomenclature. It is assigned to the genus Conularia with similarities to Baltoscandian conulariids. The lithology of the erratic boulder and fauna contained in it provide important information on the origin and transport direction of the sediment preserved in a kame from the Saalian glaciation. This paper deals with the site of origin of the boulder in Baltoscandia analysing the comprised palaeofauna, from a palaeostratigraphic and palaeogeographic point of view, from its deposition in Ordovician times until its arrival at its current location in the Late Pleistocene. It also reveals for the first time the internal structure of the conulariid aperture.

scholarly journals PHOTOCHEMICAL DEGRADATION OF PHENOL WITH THE PARTICIPATION OF TiO2 NANOPARTICLES AND ETHYL-3,3,5,5-TETRACIANO-2-HYDROXIDE-2-METIL-4,6-DIPHENYL CYCLOHEXANE CARBOXYLATE

2021 ◽  
pp. 101-105
Author(s):  
E.M. Gadirova ◽  
Keyword(s):  
Tio2 Nanoparticles ◽  
Uv Irradiation ◽  
Uv Spectroscopy ◽  
Nano Particles ◽  
Photochemical Degradation ◽  
Cyclohexane Carboxylate ◽  
Photochemical Decomposition ◽  
First Time

The photochemical decomposition of phenol with the participation of TiO2 nano-particles and ethyl-3,3,5,5-tetraciano-2-hydroxide-2-metil-4,6-diphenyl cyclohexane carboxylate by UV spectroscopy was studied for the first time. It has been shown, that UV irradiation of this mixture during 1 hour brings to 52% decomposition of phenol

scholarly journals Effects of Calcium Phosphate Nanoparticles on Ca-PO4 Composite

2007 ◽  
Vol 86 (4) ◽  
pp. 378-383 ◽  
Author(s):  
H.H.K. Xu ◽  
M.D. Weir ◽  
L. Sun ◽  
S. Takagi ◽  
L.C. Chow
Keyword(s):  
Volume Fraction ◽  
High Strength ◽  
Nano Particles ◽  
Nano Silica ◽  
Ion Release ◽  
Mass Fractions ◽  
Calcium Phosphate Nanoparticles ◽  
Filler Mass ◽  
First Time ◽  
Filler Level

Nano-particles of dicalcium phosphate anhydrous (DCPA) were synthesized for the first time. The objectives of this study were to incorporate DCPA nano-particles into resin for Ca-PO4 release to combat dental caries, and to investigate the filler level effects. Nano-DCPA and nano-silica-fused silicon nitride whiskers at a 1:1 ratio were used at filler mass fractions of 0–75%. The flexural strengths in MPa (mean ± SD; n = 6) of DCPA-whisker composites ranged from (106 ± 39) at 0% fillers to (114 ± 23) at 75% fillers, similar to (112 ± 22) of a non-releasing composite (TPH) (p > 0.1). The composite with 75% fillers in a NaCl solution (133 mmol/L, pH = 7.4, 37°C) yielded a Ca concentration of (0.65 ± 0.02) mmol/L and PO4 of (2.29 ± 0.07) mmol/L. Relationships were established between ion-release and DCPA volume fraction VDCPA: Ca = 4.46 VDCPA1.6, and = 66.9 VDCPA2.6. Nano-DCPA-whisker PO4 composites had high strength and released high levels of Ca-PO4 requisite for remineralization. These new nano-composites could provide the needed combination of stress-bearing and caries-inhibiting capabilities.

Seeing the Big Picture

2001 ◽  
Author(s):  
Leslee Bartlet
Keyword(s):  
Internal Structure ◽  
Subject Matter ◽  
Educational Philosophy ◽  
Community Of Learners ◽  
Group Discussions ◽  
Initial Impression ◽  
Big Picture ◽  
First Time

When someone walks into our community of learners for the first time, his or her initial impression is often one of chaos. How can you tell what anyone is doing? Why are those children under the table? Who is watching the ones in the hall? The range of activity may include a lone reader curled high in a loft, an animated group involved in a dice game, or several students in elaborate costume refining the dialogue of their latest play. A visitor may also be hard put to identify the teacher among the four or five adults scattered throughout the room. That suited gentleman on his knees by the computers? The guy in jeans and T-shirt at a table, laughing with five children over a storybook? The woman in a flowing skirt sitting cross-legged on the floor, surrounded by young mathematicians intently measuring their row of brightly colored cubes? All look equally engaged with the students—no one is sitting at the desk in the corner! If the visitor pauses more than a moment or two, however, at least one of the adults (and, most likely, several children) will excuse him- or herself from the group and approach the newcomer: While from the outside it may seem impossible to detect much of anything, once you're in the know—on the inside—the slightest variation in activity is immediately apparent. All well-run classrooms, regardless of educational philosophy, have a highly developed internal structure that is invisible to the uninitiated, consisting of the philosophy and practices that help participants determine expectations for themselves and others. These are the “cultural” guidelines—surrounding subject matter, group discussions, playtime, and so on—that allow students to settle into a familiar pattern and free them to explore their learning. This internal structure determines how children learn with their teacher, each other, the parents, and the materials they use in the classroom. It's the structure that sets up boundaries for communication, outlining when and how students relate to one another during the day.

scholarly journals Sunspot Seismology Theory

1990 ◽  
Vol 142 ◽  
pp. 149-157
Author(s):  
Joseph M. Davila
Keyword(s):  
Current Knowledge ◽  
Active Regions ◽  
Wavelength Dependence ◽  
Wave Power ◽  
Subsurface Structure ◽  
Scattering Process ◽  
Mode Wave ◽  
Physical Mechanisms ◽  
First Time

Recent observations have demonstrated that sunspots can absorb significant p-mode wave power, and that this absorption has a well defined wavelength dependence. These observations open, for the first time, the potential to deduce semi-empirically the subsurface structure of sunspots and active regions. Several physical mechanisms have been proposed to explain the absorption. In this paper, the proposed mechanisms are reviewed and their viability in view of the current knowledge of the scattering process is discussed.

Self Organized Growth in Thulium Doped Gaas Using MBE

1996 ◽  
Vol 422 ◽  
Author(s):  
M. R. Bennett ◽  
K. E. Singer ◽  
A. C. Wright ◽  
Z. H. Jafri
Keyword(s):  
Quantum Wires ◽  
Strain Relaxation ◽  
Solubility Limit ◽  
Growth Conditions ◽  
Nano Particles ◽  
Uniform Size ◽  
Self Organized ◽  
High Resolution Tem ◽  
Doping Profiles ◽  
First Time

AbstractThe growth of epitaxial GaAs doped with the rare earth thulium (Tm) by MBE is reported for the first time. The nature of the incorporation of Tm has been studied using SIMS, RBS, TEM, PL and DCXRD. Sharp doping profiles have been observed by SIMS from samples doped in a staircase structure. Under standard GaAs growth conditions, TEM has revealed a solubility limit of ∼5×1019cm−3, above which Tm precipitates as spherical nano-particles of uniform size (1.3–1.7nm). High resolution TEM has provided no evidence for strain relaxation around these precipitates. Growth at higher substrate temperatures (≥620°C) or at As:Ga ratios close to stoichiometry, results in the formation of precipitate wires and/or bifurcated structures (“quantum trees”) aligned approximately in the direction of growth. Such behaviour is in common with that of Er in GaAs and suggests that the precipitates result from the self-organised growth of TmAs. Mechanisms for the formation of the quantum wires and trees are suggested. Initial photoluminescence spectra from these samples show two groups of narrow Tm3+ intra 4f transition lines corresponding to the 3H5 – 3H6 (∼1.01eV/1.2μm) and 3H4 – 3H6 (∼ 0.71eV/1.7μm) transitions. The spectra exhibit an excellent correlation with those obtained from samples grown by MOVPE and also those implanted with Tm by other groups.

scholarly journals Programming function into mechanical forms by directed assembly of silk bulk materials

2016 ◽  
Vol 114 (3) ◽  
pp. 451-456 ◽  
Author(s):  
Benedetto Marelli ◽  
Nereus Patel ◽  
Thomas Duggan ◽  
Giovanni Perotto ◽  
Elijah Shirman ◽  
...  
Keyword(s):  
Self Assembly ◽  
Biological Function ◽  
Bulk Material ◽  
Directed Assembly ◽  
Water Soluble ◽  
Infrared Light ◽  
Bulk Materials ◽  
Protein Matrix ◽  
On Demand ◽  
Water Based

We report simple, water-based fabrication methods based on protein self-assembly to generate 3D silk fibroin bulk materials that can be easily hybridized with water-soluble molecules to obtain multiple solid formats with predesigned functions. Controlling self-assembly leads to robust, machinable formats that exhibit thermoplastic behavior consenting material reshaping at the nanoscale, microscale, and macroscale. We illustrate the versatility of the approach by realizing demonstrator devices where large silk monoliths can be generated, polished, and reshaped into functional mechanical components that can be nanopatterned, embed optical function, heated on demand in response to infrared light, or can visualize mechanical failure through colorimetric chemistries embedded in the assembled (bulk) protein matrix. Finally, we show an enzyme-loaded solid mechanical part, illustrating the ability to incorporate biological function within the bulk material with possible utility for sustained release in robust, programmably shapeable mechanical formats.

scholarly journals Studies on Marine Flagellates IV. Morphology and Microanatomy of a new Species of Chrysochromulina

1958 ◽  
Vol 37 (1) ◽  
pp. 209-228 ◽  
Author(s):  
Mary Parke ◽  
Irene Manton ◽  
B. Clarke
Keyword(s):  
Electron Microscopy ◽  
New Species ◽  
Internal Structure ◽  
Surface Membrane ◽  
The Body ◽  
Diagnostic Characters ◽  
Unsaturated Fat ◽  
Fat Bodies ◽  
First Time ◽  
A New Species

The description of a new species of the genus Chrysochromulina, C. chiton, includes for the first time some evidence from the electron microscopy of sections in addition to the techniques previously used. Important diagnostic characters are the exceptionally large scales, which are shown to be of two kinds, the larger being saucer-shaped, and the smaller plate-like with a narrow rim flexed towards the upper surface; the structure and arrangement of the two types of scale on the body are described. Anatomical facts are given for the first time for the internal structure of the haptonema; in this species this organ consists of three concentric membranes surrounding a ring of seven fibres or tubes, the centre of the haptonema being hollow; this combination of characters distinguishes the organ fundamentally from a flagellum. Microanatomical facts are also given for the following major cell organs: the nucleus, the chromatophores including the pyrenoids, mitochondria, putative golgi material, muciferous bodies, the flagellar bases (preliminary observations only). Other distinguishable cytoplasmic components include the surface membrane, unsaturated fat bodies, vesicles of various kinds and granular protoplasm in the interstices.

Giant Piezoelectric and Dielectric Relaxations in Statistical Mixtures

2006 ◽  
Vol 115 ◽  
pp. 209-214
Author(s):  
A.I. Chernobabov ◽  
A.V. Turik ◽  
G.S. Radchenko ◽  
S.A. Turik
Keyword(s):  
Dielectric Permittivity ◽  
Aspect Ratio ◽  
Heterogeneous Systems ◽  
Dielectric Constants ◽  
Dielectric Spectra ◽  
Physical Mechanisms ◽  
Dielectric Relaxations ◽  
First Time

The effective complex piezoelectric and dielectric constants of disordered heterogeneous systems of the type of statistical mixtures with the components in the form of spheroid-shaped particles equally oriented but randomly arranged in space were studied. It has been found for the first time that in such systems there appears a giant piezoelectric enhancement accompanied by a giant relaxation of piezoelectric coefficients and the dielectric permittivity. Piezoelectric and dielectric spectra differ significantly from the Debye ones and are of Davidson-Cole type. The influence of the aspect ratio of spheroids on the effects under consideration was studied. The physical mechanisms responsible for the anomalies in the behavior of piezoelectric coefficients and the dielectric permittivity were considered.

scholarly journals Formation of nanoscopic CaF2via a fluorolytic sol–gel process for antireflective coatings

2015 ◽  
Vol 3 (8) ◽  
pp. 1716-1723 ◽  
Author(s):  
Alexander Rehmer ◽  
Kerstin Scheurell ◽  
Erhard Kemnitz
Keyword(s):  
Sol Gel ◽  
Nano Particles ◽  
Antireflective Coatings ◽  
Sol Gel Process ◽  
Sol Gel Synthesis ◽  
First Time

For the first time transparent antireflective CaF2-coatings were prepared from clear CaF2-sols obtained via the fluorolytic sol–gel synthesis and containing homo-dispersed CaF2 nano-particles.

Sign in / Sign up

Export Citation Format

Share Document