scholarly journals Brilliant angle-independent structural colours preserved in weevil scales from the Swiss Pleistocene

2020 ◽  
Vol 16 (4) ◽  
pp. 20200063
Author(s):  
Luke T. McDonald ◽  
Suresh Narayanan ◽  
Alec Sandy ◽  
Vinodkumar Saranathan ◽  
Maria E. McNamara
Keyword(s):  
Fossil Record ◽  
Evolutionary History ◽  
Three Dimensional ◽  
Far Field ◽  
Poor Knowledge ◽  
X Ray ◽  
Evolutionary Origins ◽  
X Ray Scattering ◽  
Colour Palette ◽  
Scanning Electron

Extant weevils exhibit a remarkable colour palette that ranges from muted monochromatic tones to rainbow-like iridescence, with the most vibrant colours produced by three-dimensional photonic nanostructures housed within cuticular scales. Although the optical properties of these nanostructures are well understood, their evolutionary history is not fully resolved, in part due to a poor knowledge of their fossil record. Here, we report three-dimensional photonic nanostructures preserved in brightly coloured scales of two weevils, belonging to the genus Phyllobius or Polydrusus , from the Pleistocene (16–10 ka) of Switzerland. The scales display vibrant blue, green and yellow hues that resemble those of extant Phyllobius/Polydrusus . Scanning electron microscopy and small-angle X-ray scattering analyses reveal that the subfossil scales possess a single-diamond photonic crystal nanostructure. In extant Phyllobius/Polydrusus , the near-angle-independent blue and green hues function primarily in crypsis. The preservation of far-field, angle-independent structural colours in the Swiss subfossil weevils and their likely function in substrate matching confirm the importance of investigating fossil and subfossil photonic nanostructures to understand the evolutionary origins and diversification of colours and associated behaviours (e.g. crypsis) in insects.

X-ray imaging with ultra-small-angle X-ray scattering as a contrast mechanism

2004 ◽  
Vol 37 (5) ◽  
pp. 757-765 ◽  
Author(s):  
L. E. Levine ◽  
G. G. Long
Keyword(s):  
Small Angle ◽  
Imaging Technique ◽  
Three Dimensional ◽  
Sample Volume ◽  
Contrast Imaging ◽  
X Ray ◽  
X Ray Scattering ◽  
X Ray Imaging ◽  
Contrast Mechanism ◽  
Ray Scattering

A new transmission X-ray imaging technique using ultra-small-angle X-ray scattering (USAXS) as a contrast mechanism is described. USAXS imaging can sometimes provide contrast in cases where radiography and phase-contrast imaging are unsuccessful. Images produced at different scattering vectors highlight different microstructural features within the same sample volume. When used in conjunction with USAXS scans, USAXS imaging provides substantial quantitative and qualitative three-dimensional information on the sizes, shapes and spatial arrangements of the scattering objects. The imaging technique is demonstrated on metal and biological samples.

Facile Fabrication of Flower-Like LLM-105 Three-Dimensional Microstructures

2011 ◽  
Vol 239-242 ◽  
pp. 2942-2945 ◽  
Author(s):  
Jin Chen ◽  
Li Li Wang ◽  
Guang Cheng Yang ◽  
Zhi Qiang Qiao ◽  
Fu De Nie
Keyword(s):  
Cross Sections ◽  
Three Dimensional ◽  
Raw Material ◽  
Differential Scanning Calorimetric ◽  
Recrystallization Process ◽  
X Ray ◽  
Facile Fabrication ◽  
Lower Temperature ◽  
Scanning Electron ◽  
Poor Solvent

Flower-like LLM-105 three-dimensional microstructures, which consisted of LLM-105 microrods with rectangular cross-sections, were prepared via a smiple template- and surfactant-free recrystallization process using [Bmim]CF3SO3as good solvent and water as poor solvent. A tentative mechanism for the growth of the flower-like LLM-105 three-dimensional microstructures was proposed on the basis of the analysis of X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). Comparing with LLM-105 raw material, the thermal decomposition took place at lower temperature and the weight loss has increased for the flower-like three-dimensional microstructures in the differential scanning calorimetric/thermogravimetric (DSC/TG) measurements.

Three-dimensional structure of the calcite–water interface by surface X-ray scattering

2004 ◽  
Vol 573 (2) ◽  
pp. 191-203 ◽  
Author(s):  
P. Geissbühler ◽  
P. Fenter ◽  
E. DiMasi ◽  
G. Srajer ◽  
L.B. Sorensen ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Dimensional Structure ◽  
Water Interface ◽  
X Ray ◽  
Three Dimensional Structure ◽  
X Ray Scattering ◽  
Ray Scattering

scholarly journals Supercritical CO2extraction of porogen phase: An alternative route to nanoporous dielectrics

2004 ◽  
Vol 19 (11) ◽  
pp. 3224-3233 ◽  
Author(s):  
J.A. Lubguban ◽  
S. Gangopadhyay ◽  
B. Lahlouh ◽  
T. Rajagopalan ◽  
N. Biswas ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Selective Extraction ◽  
Porous Structures ◽  
Saxs Data ◽  
3D Images ◽  
X Ray ◽  
X Ray Scattering ◽  
Through Diffusion ◽  
Organosilicate Thin Films ◽  
Poly Propylene

We present a supercritical CO2(SCCO2) process for the preparation of nanoporous organosilicate thin films for ultralow dielectric constant materials. The porous structure was generated by SCCO2extraction of a sacrificial poly(propylene glycol) (PPG) from a nanohybrid film, where the nanoscopic domains of PPG porogen are entrapped within the crosslinked poly(methylsilsesquioxane) (PMSSQ) matrix. As a comparison, porous structures generated by both the usual thermal decomposition (at approximately 450 °C) and by a SCCO2process for 25 and 55 wt% porogen loadings were evaluated. It is found that the SCCO2process is effective in removing the porogen phase at relatively low temperatures (<200 °C) through diffusion of the supercritical fluid into the phase-separated nanohybrids and selective extraction of the porogen phase. Pore morphologies generated from the two methods are compared from representative three-dimensional (3D) images built from small-angle x-ray scattering (SAXS) data.

The formation and characterization of three-dimensional gold nanocrystal superlattices

2007 ◽  
Vol 222 (11/2007) ◽  
Author(s):  
Michael G. Constantinides ◽  
Heinrich M. Jaeger ◽  
Xuefa Li ◽  
Jin Wang ◽  
Xiao-Min Lin
Keyword(s):  
Thermal Stability ◽  
Three Dimensional ◽  
Grazing Incidence ◽  
Gold Nanocrystals ◽  
X Ray ◽  
X Ray Scattering ◽  
Drop Drying ◽  
Nanocrystal Superlattices ◽  
Gold Nanocrystal

Highly-ordered, three-dimensional superlattices were self-assembled from dodecanethiol-ligated gold nanocrystals using a simple drop-drying technique. The superlattices had the shape of truncated pyramids (frustums) and reached lateral dimensions of several micrometers. The formation and thermal stability were studied by grazing-incidence small-angle x-ray scattering. We found that the superlattice frustums adopt a

Pore and mineral structure of rock using nano-tomographic imaging

2015 ◽  
Vol 1744 ◽  
pp. 235-240 ◽  
Author(s):  
Jukka Kuva ◽  
Mikko Voutilainen ◽  
Antero Lindberg ◽  
Joni Parkkonen ◽  
Marja Siitari-Kauppi ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Three Dimensional ◽  
Potassium Feldspar ◽  
Dimensional Structure ◽  
Good Tool ◽  
X Ray ◽  
Mineral Structure ◽  
Micrometer Scale ◽  
Scanning Electron

ABSTRACTIn order to better understand the micrometer-scale structure of rock and its transport properties which arise from it, seven monomineral samples from two sites (Olkiluoto and Sievi, Finland) were studied with micro- and nanotomography and scanning electron microscopy. From the veined gneiss of Olkiluoto we studied biotite, potassium feldspar, plagioclase (composition of oligoclase) and cordierite, and from Sievi tonalite biotite and two grains of plagioclase (albite). These minerals were the main minerals of these samples. Samples were carefully separated and selected using heavy liquid separation and stereomicroscopy, their three dimensional structure was imaged using X-ray tomography, and their precise mineral composition was determined using scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM/EDS). The micrometer-scale mineral structure of these samples was observed together with their pores and fissures, and alteration effects were identified whenever applicable. Nanotomography combined with SEM analysis was concluded to be a good tool for analyzing effects of alteration in monomineral samples.

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