Mechanism by which three-dimensional ordered mesoporous CeO2 promotes the activity of VOx-MnOx/CeO2 catalysts for NOx abatement: Atomic-scale insight into the catalytic cycle

The synaptic connections in cat retina that link photoreceptors to ganglion cells have been analyzed quantitatively. Our approach has been to prepare serial, ultrathin sections and photograph en montage at low magnification (˜2000X) in the electron microscope. Six series, 100-300 sections long, have been prepared over the last decade. They derive from different cats but always from the same region of retina, about one degree from the center of the visual axis. The material has been analyzed by reconstructing adjacent neurons in each array and then identifying systematically the synaptic connections between arrays. Most reconstructions were done manually by tracing the outlines of processes in successive sections onto acetate sheets aligned on a cartoonist's jig. The tracings were then digitized, stacked by computer, and printed with the hidden lines removed. The results have provided rather than the usual one-dimensional account of pathways, a three-dimensional account of circuits. From this has emerged insight into the functional architecture.

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Fabrication and Excellent Catalytic Performance of Three-dimensional Ordered Mesoporous Molybdenum Oxides

Journal of Inorganic Materials ◽

10.3724/sp.j.1077.2014.13233 ◽

2014 ◽

Vol 29 (2) ◽

pp. 124-130 ◽

Cited By ~ 3

Author(s):

Yu-Cheng DU ◽

Guang-Wei ZHENG ◽

Qi MENG ◽

Li-Ping WANG ◽

Hai-Guang FAN ◽

...

Keyword(s):

Three Dimensional ◽

Catalytic Performance ◽

Molybdenum Oxides ◽

Ordered Mesoporous ◽

Excellent Catalytic Performance

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Completely non-fused electron acceptor with 3D-interpenetrated crystalline structure enables efficient and stable organic solar cell

Nature Communications ◽

10.1038/s41467-021-25394-w ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Lijiao Ma ◽

Shaoqing Zhang ◽

Jincheng Zhu ◽

Jingwen Wang ◽

Junzhen Ren ◽

...

Keyword(s):

Organic Solar Cell ◽

Low Cost ◽

Three Dimensional ◽

Molecular Geometry ◽

Interpenetrating Network ◽

Fused Ring ◽

Molecule Design ◽

End Capping ◽

Conversion Efficiencies ◽

Insight Into

AbstractNon-fullerene acceptors (NFAs) based on non-fused conjugated structures have more potential to realize low-cost organic photovoltaic (OPV) cells. However, their power conversion efficiencies (PCEs) are much lower than those of the fused-ring NFAs. Herein, a new bithiophene-based non-fused core (TT-Pi) featuring good planarity as well as large steric hindrance was designed, based on which a completely non-fused NFA, A4T-16, was developed. The single-crystal result of A4T-16 reveals that a three-dimensional interpenetrating network can be formed due to the compact π–π stacking between the adjacent end-capping groups. A high PCE of 15.2% is achieved based on PBDB-TF:A4T-16, which is the highest value for the cells based on the non-fused NFAs. Notably, the device retains ~84% of its initial PCE after 1300 h under the simulated AM 1.5 G illumination (100 mW cm−2). Overall, this work provides insight into molecule design of the non-fused NFAs from the aspect of molecular geometry control.

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Porous Characteristics of Three-Dimensional Disordered Graphene Networks

Crystals ◽

10.3390/cryst11020127 ◽

2021 ◽

Vol 11 (2) ◽

pp. 127

Author(s):

YongChao Wang ◽

YinBo Zhu ◽

HengAn Wu

Keyword(s):

Pore Size ◽

Low Temperatures ◽

Gas Adsorption ◽

Three Dimensional ◽

Md Simulations ◽

Structural Features ◽

Atomic Scale ◽

Critical Factors ◽

Chlorination Process ◽

Porous Morphology

The porous characteristics of disordered carbons are critical factors to their performance on hydrogen storage and electrochemical capacitors. Even though the porous information can be estimated indirectly by gas adsorption experiments, it is still hard to directly characterize the porous morphology considering the complex 3D connectivity. To this end, we construct full-atom disordered graphene networks (DGNs) by mimicking the chlorination process of carbide-derived carbons using annealing-MD simulations, which could model the structure of disordered carbons at the atomic scale. The porous characteristics, including pore volume, pore size distribution (PSD), and specific surface area (SSA), were then computed from the coordinates of carbon atoms. From the evolution of structural features, pores grow dramatically during the formation of polyaromatic fragments and sequent disordered framework. Then structure is further graphitized while the PSD shows little change. For the obtained DGNs, the porosity, pore size, and SSA increase with decreasing density. Furthermore, SSA tends to saturate in the low-density range. The DGNs annealed at low temperatures exhibit larger SSA than high-temperature DGNs because of the abundant free edges.

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The distribution of myosin II in Dictyostelium discoideum slug cells.

The Journal of Cell Biology ◽

10.1083/jcb.115.5.1267 ◽

1991 ◽

Vol 115 (5) ◽

pp. 1267-1274 ◽

Cited By ~ 12

Author(s):

S Eliott ◽

P H Vardy ◽

K L Williams

Keyword(s):

Cell Motility ◽

Dictyostelium Discoideum ◽

Immunofluorescence Microscopy ◽

Molecular Genetic ◽

Myosin Ii ◽

Three Dimensional ◽

Homogeneous Distribution ◽

Multicellular Development ◽

Insight Into

While the role of myosin II in muscle contraction has been well characterized, less is known about the role of myosin II in non-muscle cells. Recent molecular genetic experiments on Dictyostelium discoideum show that myosin II is necessary for cytokinesis and multicellular development. Here we use immunofluorescence microscopy with monoclonal and polyclonal antimyosin antibodies to visualize myosin II in cells of the multicellular D. discoideum slug. A subpopulation of peripheral and anterior cells label brightly with antimyosin II antibodies, and many of these cells display a polarized intracellular distribution of myosin II. Other cells in the slug label less brightly and their cytoplasm displays a more homogeneous distribution of myosin II. These results provide insight into cell motility within a three-dimensional tissue and they are discussed in relation to the possible roles of myosin II in multicellular development.

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Thermal Design of Highly-Efficient Thermoelectric Materials With Atomic-Scale Three-Dimensional Phononic Crystals

Volume 10: Mechanics of Solids and Structures, Parts A and B ◽

10.1115/imece2007-43538 ◽

2007 ◽

Author(s):

Jean-Numa Gillet ◽

Yann Chalopin ◽

Sebastian Volz

Keyword(s):

Thermal Conductivity ◽

Bulk Material ◽

Phononic Crystal ◽

Three Dimensional ◽

Mean Free Path ◽

Dispersion Curves ◽

Phononic Crystals ◽

Thermal Design ◽

Atomic Scale ◽

Thermal Insulating

Owing to their thermal insulating properties, superlattices have been extensively studied. A breakthrough in the performance of thermoelectric devices was achieved by using superlattice materials. The problem of those nanostructured materials is that they mainly affect heat transfer in only one direction. In this paper, the concept of canceling heat conduction in the three spatial directions by using atomic-scale three-dimensional (3D) phononic crystals is explored. A period of our atomic-scale 3D phononic crystal is made up of a large number of diamond-like cells of silicon atoms, which form a square supercell. At the center of each supercell, we substitute a smaller number of Si diamond-like cells by other diamond-like cells, which are composed of germanium atoms. This elementary heterostructure is periodically repeated to form a Si/Ge 3D nanostructure. To obtain different atomic configurations of the phononic crystal, the number of Ge diamond-like cells at the center of each supercell can be varied by substitution of Si diamond-like cells. The dispersion curves of those atomic configurations can be computed by lattice dynamics. With a general equation, the thermal conductivity of our atomic-scale 3D phononic crystal can be derived from the dispersion curves. The thermal conductivity can be reduced by at least one order of magnitude in an atomic-scale 3D phononic crystal compared to a bulk material. This reduction is due to the decrease of the phonon group velocities without taking into account that of the phonon average mean free path.

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Analysis of SiC CVD Growth in a Horizontal Hot-Wall Reactor by Experiment and 3D Modelling

Materials Science Forum ◽

10.4028/www.scientific.net/msf.556-557.61 ◽

2007 ◽

Vol 556-557 ◽

pp. 61-64

Author(s):

Y. Shishkin ◽

Rachael L. Myers-Ward ◽

Stephen E. Saddow ◽

Alexander Galyukov ◽

A.N. Vorob'ev ◽

...

Keyword(s):

Growth Rate ◽

Growth Process ◽

Three Dimensional ◽

Chemical Species ◽

3D Modelling ◽

Complete Model ◽

Cvd Growth ◽

Dimensional Simulation ◽

Insight Into ◽

Hot Zone

A fully-comprehensive three-dimensional simulation of a CVD epitaxial growth process has been undertaken and is reported here. Based on a previously developed simulation platform, which connects fluid dynamics and thermal temperature profiling with chemical species kinetics, a complete model of the reaction process in a low pressure hot-wall CVD reactor has been developed. Close agreement between the growth rate observed experimentally and simulated theoretically has been achieved. Such an approach should provide the researcher with sufficient insight into the expected growth rate in the reactor as well as any variations in growth across the hot zone.

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New insight into the role of inclusions in hydrogen-induced degradation of fracture toughness: three-dimensional imaging and modeling

The Philosophical Magazine A Journal of Theoretical Experimental and Applied Physics ◽

10.1080/14786435.2021.1876267 ◽

2021 ◽

pp. 1-21

Author(s):

K.M.M. Rahman ◽

W. Qin ◽

J.A. Szpunar ◽

J. Kozinski ◽

M. Song ◽

...

Keyword(s):

Fracture Toughness ◽

Three Dimensional ◽

Three Dimensional Imaging ◽

Insight Into

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The Three-Dimensional Surface Topographic Characterisation of Diamond Grinding Wheels

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.126-128.690 ◽

2010 ◽

Vol 126-128 ◽

pp. 690-695

Author(s):

David Lee Butler

Keyword(s):

Measurement Techniques ◽

Three Dimensional ◽

Surface Measurement ◽

Grinding Wheel ◽

Profile Measurement ◽

Detailed Knowledge ◽

Grinding Wheels ◽

Diamond Grinding ◽

Insight Into ◽

Dimensional Surface

Surface measurement using three-dimensional stylus instruments is a relatively new technique that offers numerous advantages over more traditional profilometry methods. The information generated is, unlike profile measurement, less subjective and more statistical providing additional insight into the surface structure. One application of surface measurement that has encountered problems when using the profilometry method is that of grinding wheel characterisation. The wheel surface texture (topography) and the conditions under which it is generated have a profound effect upon the grinding performance as characterised by the grinding forces, power consumption, temperature, and surface integrity of components. A detailed knowledge of the nature of the topography of the grinding wheel would provide further insight into surface interactions between the wheel and workpiece as well as enabling improved control of the grinding process in general. In this paper four diamond grinding wheels of 91 and 181 micron grit size were subjected to differing dressing conditions to produce varying final wheel topographies. Three-dimensional surface measurement techniques were employed to quantitatively characterise the topographic change and provide an aerial estimation of the number of cutting grains. The results demonstrate that the techniques can distinguish between a worn and dressed wheel. In addition, the parametric values generated from the various surfaces can aid the user in determining when re-dressing is required.

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