Layered macrocycles with flexibility and tunable dynamic properties for wide-range thermoresponsive color changes

Layered materials exhibit unique properties, such as intercalation and exfoliation, originating from the two-dimensional anisotropic nanostructures. A variety of inorganic and organic layered materials have been synthesized for design of...

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Two-dimensional inorganic analogues of graphene: transition metal dichalcogenides

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2015.0318 ◽

2016 ◽

Vol 374 (2076) ◽

pp. 20150318 ◽

Cited By ~ 42

Author(s):

Manoj K. Jana ◽

C. N. R. Rao

Keyword(s):

Transition Metal ◽

Transition Metal Dichalcogenides ◽

Single Layer ◽

Layered Materials ◽

Two Dimensional ◽

2D Layered Materials ◽

Wide Range ◽

Buckminster Fullerene ◽

Metal Dichalcogenides ◽

Layered Transition Metal

The discovery of graphene marks a major event in the physics and chemistry of materials. The amazing properties of this two-dimensional (2D) material have prompted research on other 2D layered materials, of which layered transition metal dichalcogenides (TMDCs) are important members. Single-layer and few-layer TMDCs have been synthesized and characterized. They possess a wide range of properties many of which have not been known hitherto. A typical example of such materials is MoS 2 . In this article, we briefly present various aspects of layered analogues of graphene as exemplified by TMDCs. The discussion includes not only synthesis and characterization, but also various properties and phenomena exhibited by the TMDCs. This article is part of the themed issue ‘Fullerenes: past, present and future, celebrating the 30th anniversary of Buckminster Fullerene’.

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Aromatic Volatile Composition of Celery and Celeriac Cultivars

HortScience ◽

10.21273/hortsci.25.5.556 ◽

1990 ◽

Vol 25 (5) ◽

pp. 556-559 ◽

Cited By ~ 19

Author(s):

Fredy Van Wassenhove ◽

Patrick Dirinck ◽

Georges Vulsteke ◽

Niceas Schamp

Keyword(s):

Volatile Compounds ◽

Chromatographic Method ◽

Apium Graveolens ◽

Volatile Components ◽

Two Dimensional ◽

Qualitative Composition ◽

Volatile Composition ◽

Wide Range ◽

Gas Chromatographic Method ◽

Identification And Quantification

A two-dimensional capillary gas chromatographic method was developed to separate and quantify aromatic volatiles of celery in one analysis. The isolation, identification, and quantification of the volatile compounds of four cultivars of blanching celery (Apium graveolens L. var. dulce) and six cultivars of celeriac (Apium graveolens L. var. rapaceum) are described. The qualitative composition of Likens-Nickerson extracts of both cultivars is similar. The concentration of terpenes and phthalides, the key volatile components, found in various cultivars of both celery and celeriac varied over a wide range.

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Preparation of two-dimensional [Bi2O2]-based layered materials: Progress and prospects

APL Materials ◽

10.1063/5.0052300 ◽

2021 ◽

Vol 9 (6) ◽

pp. 060905

Author(s):

Yan Liang ◽

Xuehan Zhou ◽

Wen Li ◽

Hailin Peng

Keyword(s):

Layered Materials ◽

Two Dimensional

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Simulation Verification of the Contact Parameter Influence on the Forces’ Course of Cereal Grain Impact against a Stiff Surface

Applied Sciences ◽

10.3390/app11020466 ◽

2021 ◽

Vol 11 (2) ◽

pp. 466

Author(s):

Włodzimierz Kęska ◽

Jacek Marcinkiewicz ◽

Łukasz Gierz ◽

Żaneta Staszak ◽

Jarosław Selech ◽

...

Keyword(s):

Dynamic Properties ◽

Decisive Role ◽

Force Sensor ◽

Contact Forces ◽

Correct Selection ◽

Contact Parameter ◽

Cereal Grain ◽

Wide Range ◽

The Impact ◽

Selection Of

The continuous development of computer technology has made it applicable in many scientific fields, including research into a wide range of processes in agricultural machines. It allows the simulation of very complex physical phenomena, including grain motion. A recently discovered discrete element method (DEM) is used for this purpose. It involves direct integration of equations of grain system motion under the action of various forces, the most important of which are contact forces. The method’s accuracy depends mainly on precisely developed mathematical models of contacts. The creation of such models requires empirical validation, an experiment that investigates the course of contact forces at the moment of the impact of the grains. To achieve this, specialised test stations equipped with force and speed sensors were developed. The correct selection of testing equipment and interpretation of results play a decisive role in this type of research. This paper focuses on the evaluation of the force sensor dynamic properties’ influence on the measurement accuracy of the course of the plant grain impact forces against a stiff surface. The issue was examined using the computer simulation method. A proprietary computer software with the main calculation module and data input procedures, which presents results in a graphic form, was used for calculations. From the simulation, graphs of the contact force and force signal from the sensor were obtained. This helped to clearly indicate the essence of the correct selection of parameters used in the tests of sensors, which should be characterised by high resonance frequency.

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Prediction of Wide Range Two-Dimensional Refractivity Using an IDW Interpolation Method from High-Altitude Refractivity Data of Multiple Meteorological Observatories

Applied Sciences ◽

10.3390/app11041431 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1431

Author(s):

Sungsik Wang ◽

Tae Heung Lim ◽

Kyoungsoo Oh ◽

Chulhun Seo ◽

Hosung Choo

Keyword(s):

High Altitude ◽

Korean Peninsula ◽

Interpolation Method ◽

Atmospheric Condition ◽

Propagation Path ◽

Two Dimensional ◽

Data Set ◽

Wide Range ◽

Atmospheric Data ◽

Terrain Surface

This article proposes a method for the prediction of wide range two-dimensional refractivity for synthetic aperture radar (SAR) applications, using an inverse distance weighted (IDW) interpolation of high-altitude radio refractivity data from multiple meteorological observatories. The radio refractivity is extracted from an atmospheric data set of twenty meteorological observatories around the Korean Peninsula along a given altitude. Then, from the sparse refractive data, the two-dimensional regional radio refractivity of the entire Korean Peninsula is derived using the IDW interpolation, in consideration of the curvature of the Earth. The refractivities of the four seasons in 2019 are derived at the locations of seven meteorological observatories within the Korean Peninsula, using the refractivity data from the other nineteen observatories. The atmospheric refractivities on 15 February 2019 are then evaluated across the entire Korean Peninsula, using the atmospheric data collected from the twenty meteorological observatories. We found that the proposed IDW interpolation has the lowest average, the lowest average root-mean-square error (RMSE) of ∇M (gradient of M), and more continuous results than other methods. To compare the resulting IDW refractivity interpolation for airborne SAR applications, all the propagation path losses across Pohang and Heuksando are obtained using the standard atmospheric condition of ∇M = 118 and the observation-based interpolated atmospheric conditions on 15 February 2019. On the terrain surface ranging from 90 km to 190 km, the average path losses in the standard and derived conditions are 179.7 dB and 182.1 dB, respectively. Finally, based on the air-to-ground scenario in the SAR application, two-dimensional illuminated field intensities on the terrain surface are illustrated.

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Size effects in two-dimensional layered materials modeled by couple stress elasticity

Frontiers of Structural and Civil Engineering ◽

10.1007/s11709-021-0707-y ◽

2021 ◽

Author(s):

Wipavee Wongviboonsin ◽

Panos A. Gourgiotis ◽

Chung Nguyen Van ◽

Suchart Limkatanyu ◽

Jaroon Rungamornrat

Keyword(s):

Size Effects ◽

Couple Stress ◽

Layered Materials ◽

Two Dimensional ◽

Couple Stress Elasticity

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Is contact angle a cause or an effect? – A cautionary tale

E3S Web of Conferences ◽

10.1051/e3sconf/202014603004 ◽

2020 ◽

Vol 146 ◽

pp. 03004

Author(s):

Douglas Ruth

Keyword(s):

Contact Angle ◽

Solid Surface ◽

Contact Angles ◽

Two Dimensions ◽

Experimental Results ◽

Flow In Porous Media ◽

Two Dimensional ◽

Wide Range ◽

Fluid Drop ◽

Surrounding Fluid

The most influential parameter on the behavior of two-component flow in porous media is “wettability”. When wettability is being characterized, the most frequently used parameter is the “contact angle”. When a fluid-drop is placed on a solid surface, in the presence of a second, surrounding fluid, the fluid-fluid surface contacts the solid-surface at an angle that is typically measured through the fluid-drop. If this angle is less than 90°, the fluid in the drop is said to “wet” the surface. If this angle is greater than 90°, the surrounding fluid is said to “wet” the surface. This definition is universally accepted and appears to be scientifically justifiable, at least for a static situation where the solid surface is horizontal. Recently, this concept has been extended to characterize wettability in non-static situations using high-resolution, two-dimensional digital images of multi-component systems. Using simple thought experiments and published experimental results, many of them decades old, it will be demonstrated that contact angles are not primary parameters – their values depend on many other parameters. Using these arguments, it will be demonstrated that contact angles are not the cause of wettability behavior but the effect of wettability behavior and other parameters. The result of this is that the contact angle cannot be used as a primary indicator of wettability except in very restricted situations. Furthermore, it will be demonstrated that even for the simple case of a capillary interface in a vertical tube, attempting to use simply a two-dimensional image to determine the contact angle can result in a wide range of measured values. This observation is consistent with some published experimental results. It follows that contact angles measured in two-dimensions cannot be trusted to provide accurate values and these values should not be used to characterize the wettability of the system.

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Robust anomalous metallic states and vestiges of self-duality in two-dimensional granular In-InOx composites

npj Quantum Materials ◽

10.1038/s41535-021-00329-2 ◽

2021 ◽

Vol 6 (1) ◽

Author(s):

Xinyang Zhang ◽

Bar Hen ◽

Alexander Palevski ◽

Aharon Kapitulnik

Keyword(s):

Magnetic Field ◽

Metallic Phase ◽

Broadband Noise ◽

Two Dimensional ◽

Conventional Theory ◽

Logarithmic Divergence ◽

Self Duality ◽

Low Field ◽

Wide Range ◽

Low Temperature Resistance

AbstractMany experiments investigating magnetic-field tuned superconductor-insulator transition (H-SIT) often exhibit low-temperature resistance saturation, which is interpreted as an anomalous metallic phase emerging from a ‘failed superconductor’, thus challenging conventional theory. Here we study a random granular array of indium islands grown on a gateable layer of indium-oxide. By tuning the intergrain couplings, we reveal a wide range of magnetic fields where resistance saturation is observed, under conditions of careful electromagnetic filtering and within a wide range of linear response. Exposure to external broadband noise or microwave radiation is shown to strengthen the tendency of superconductivity, where at low field a global superconducting phase is restored. Increasing magnetic field unveils an ‘avoided H-SIT’ that exhibits granularity-induced logarithmic divergence of the resistance/conductance above/below that transition, pointing to possible vestiges of the original emergent duality observed in a true H-SIT. We conclude that anomalous metallic phase is intimately associated with inherent inhomogeneities, exhibiting robust behavior at attainable temperatures for strongly granular two-dimensional systems.

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Energetics of mesoscale cell turbulence in two-dimensional monolayers

Communications Physics ◽

10.1038/s42005-021-00530-6 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Shao-Zhen Lin ◽

Wu-Yang Zhang ◽

Dapeng Bi ◽

Bo Li ◽

Xi-Qiao Feng

Keyword(s):

Kinetic Energy ◽

Tumor Metastasis ◽

Cell Types ◽

Boltzmann Distribution ◽

Scaling Exponent ◽

Biological Processes ◽

Two Dimensional ◽

Cell Monolayers ◽

Wide Range ◽

Epithelial Cell Monolayers

AbstractInvestigation of energy mechanisms at the collective cell scale is a challenge for understanding various biological processes, such as embryonic development and tumor metastasis. Here we investigate the energetics of self-sustained mesoscale turbulence in confluent two-dimensional (2D) cell monolayers. We find that the kinetic energy and enstrophy of collective cell flows in both epithelial and non-epithelial cell monolayers collapse to a family of probability density functions, which follow the q-Gaussian distribution rather than the Maxwell–Boltzmann distribution. The enstrophy scales linearly with the kinetic energy as the monolayer matures. The energy spectra exhibit a power-decaying law at large wavenumbers, with a scaling exponent markedly different from that in the classical 2D Kolmogorov–Kraichnan turbulence. These energetic features are demonstrated to be common for all cell types on various substrates with a wide range of stiffness. This study provides unique clues to understand active natures of cell population and tissues.

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