Results 21 to 30 of about 291 (152)

High-Resolution Compact On-Chip Spectrometer Based on an Echelle Grating With Densely Packed Waveguide Array

IEEE Photonics Journal, 2019
We design a 121-channel on-chip spectrometer based on an echelle grating with densely packed waveguide array on 220-nm silicon-on-insulator platform.
Keqi Ma, Kaixuan Chen, Ning Zhu, Liu Liu, Sailing He   +4 more
doaj   +1 more source

Grating monochromator wavelength calibration using an echelle grating wavelength meter [PDF]

Optics Express, 2019
Monochromators are a common utility for the spectral calibration of spectrometers. To guarantee traceability of characterization measurements to SI-standards, monochromators used as secondary standards must be properly calibrated. Common calibration procedures are based on the measurement of spectral lines emitted by gas-discharge lamps or lasers.
openaire   +3 more sources

Geological processes shaping freshwater biodiversity: a synthesis of global evidence

Biological Reviews, Volume 101, Issue 3, Page 1568-1581, June 2026.
ABSTRACT Recent genomic data highlight the key roles of geological processes in shaping the diversification and biogeography of freshwater lineages. Specifically, physical processes such as tectonic uplift, erosion, glaciation, lake formation, and sea‐level fluctuation contribute extensively to the evolution of biotic diversity within and among ...
Jonathan M. Waters, Christopher P. Burridge, David Craw, James S. Albert   +3 more
wiley   +1 more source

Phylogenetic and Environmental Insights Into the Biogeography of the Western Blacknose Dace, Rhinichthys obtusus

Ecology and Evolution, Volume 16, Issue 6, June 2026.
Pleistocene glaciations have shaped freshwater fish evolution and distribution patterns across North America. This study investigated the phylogeographical history of the Western Blacknose Dace (Rhinichthys obtusus) using mitochondrial genomic data, revealing three major clades that diverged 2–1.5 million years ago during Pleistocene glaciations when ...
Adelina Rodriguez, Timothy S. Earley, Samuel Taylor, Thomas E. Dowling, Phillip M. Harris, Jeremy Wright, Antonio Machado‐Allison, Barry Chernoff   +7 more
wiley   +1 more source

Oases of endemism: Regional aquifer desert springs serve as biodiversity hotspots preserving vulnerable endemic taxa in the Great Basin and Mojave Desert regions

Limnology and Oceanography, Volume 71, Issue 6, June 2026.
Abstract Spring ecosystems in arid regions often serve as crucial biodiversity hotspots by providing some of the only reliable sources of surface water. However, anthropogenic activities and climate change have severely degraded spring ecosystems worldwide, emphasizing the need for large‐scale multidisciplinary studies informing conservation efforts ...
Matthew J. Forrest, Donald W. Sada, Matthew S. Edwards, Robert K. Burton, Richard D. Norris   +4 more
wiley   +1 more source

Nanoscale Ordering of Magnetosomes Under the Influence of a Magnetic Field Investigated by Small‐Angle X‐Ray Scattering

Small Structures, Volume 7, Issue 6, June 2026.
Recently, the synthetic Rhodospirillum rubrum ‘magneticum’ has been shown to enable the light‐driven production of magnetosomes (MAGs) in high yields. These membrane‐enveloped magnetic nanoparticles represent promising alternatives to their chemically synthesized analogs for many applications in the biotechnological and biomedical field.
Dieter Skroblin, Sabine Rosenfeldt, Simon Markert, Jakob J. Beierl, Dirk Schüler, Anna S. Schenk, Frank Mickoleit, Christian Gollwitzer   +7 more
wiley   +1 more source

Experimental methods in chemical engineering: Atomic absorption spectrometry—AAS

The Canadian Journal of Chemical Engineering, Volume 104, Issue 5, Page 2206-2224, May 2026.
Abstract Elements absorb electromagnetic radiation (light) of a specific wavelength in proportion to the number of atoms in its path. As the atoms absorb this light energy, electrons rise from the ground state to an excited state. In atomic absorption spectrometry (AAS), high temperatures produce clouds of atoms from the sample (atomization) and ...
Emily Cintia Tossi de A. Costa, Jildimara de Jesus Santana, Viviane de Oliveira Campos, Felipe Fernandes Barbosa, Gregory S. Patience   +4 more
wiley   +1 more source

New Climatology of Martian Water Vapor Column Abundance Derived From NOMAD LNO Nadir Observations Over Martian Years 34–38

Journal of Geophysical Research: Planets, Volume 131, Issue 4, April 2026.
Abstract We present a new climatology of Martian water vapor column abundance derived from nadir dayside observations made by the Nadir and Occultation for MArs Discovery (NOMAD) instrument suite as part of the ExoMars Trace Gas Orbiter (TGO) mission. H2O vertical column densities are retrieved by applying an Optimal Estimation inversion scheme to the ...
F. Hendrick, S. Robert, I. Thomas, S. Aoki, F. Daerden, L. Trompet, L. Neary, J. Erwin, Y. Willame, A. Piccialli, Z. Flimon, B. Ristic, M. R. Patel, G. Bellucci, M. A. López‐Valverde, M. D. Smith, A. C. Vandaele   +16 more
wiley   +1 more source

Optical System Design of an Echelle Spectrometer Based on a Digital Micromirror Device

Optics
The echelle spectrometer utilizes an echelle grating as the primary dispersive element, combined with a prism or planar grating for cross-dispersion, to form a two-dimensional spectral image on an area-array Charge-Coupled Device (CCD).
Jia Liu, Ruikai Zhang, Yangdong Zhou, Dewu Li, Yixin Wang, Lu Yin   +5 more
doaj   +1 more source

Commissioning an Inexpensive Off‐The‐Shelf Spectrograph for Radial‐Velocity Studies

Astronomische Nachrichten, Volume 347, Issue 2, February 2026.
ABSTRACT We present a way to set up an inexpensive out of the shelf spectrograph at a local observatory. Stability and resolution of the spectrograph are high enough for radial velocity determination of binary stars or determination of stellar characteristics. Even some exoplanets might be detectable via the radial velocity method.
Lukas Stock, Andreas Schrimpf
wiley   +1 more source