Accurate contrast determination for X-ray speckle visibility spectroscopy.

J Synchrotron Radiat

Linac Coherent Light Source, SLAC National Accelerator Laboratory, USA.

Published: July 2020

X-ray speckle visibility spectroscopy using X-ray free-electron lasers has long been proposed as a probe of fast dynamics in noncrystalline materials. In this paper, numerical modeling is presented to show how the data interpretation of visibility spectroscopy can be impacted by the nonidealities of real-life X-ray detectors. Using simulated detector data, this work provides a detailed analysis of the systematic errors of several contrast extraction algorithms in the context of low-count-rate X-ray speckle visibility spectroscopy and their origins are discussed. Here, it was found that the finite detector charge cloud and pixel size lead to an unavoidable `degeneracy' in photon position determination, and that the contrasts extracted using different algorithms can all be corrected by a simple linear model. The results suggest that experimental calibration of the correction coefficient at the count rate of interest is possible and essential. This allows computationally lightweight algorithms to be implemented for on-the-fly analysis.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7336177PMC
http://dx.doi.org/10.1107/S1600577520006773DOI Listing

Publication Analysis

Top Keywords

visibility spectroscopy
16
x-ray speckle
12
speckle visibility
12
spectroscopy x-ray
8
x-ray
5
accurate contrast
4
contrast determination
4
determination x-ray
4
visibility
4
spectroscopy
4

Similar Publications

Newborn screening for acylcarnitine-related inherited metabolic diseases (IMDs) is a critical test after birth. Conventional extraction methods require shaking with heating, centrifugation, nitrogen blowing, redissolution, etc., and the total time is more than 1 h.

View Article and Find Full Text PDF

Near-infrared fluorogenic RNA for in vivo imaging and sensing.

Nat Commun

January 2025

Interdisciplinary Science Center, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 100101, Beijing, China.

Fluorogenic RNA aptamers have various applications, including use as fluorescent tags for imaging RNA trafficking and as indicators of RNA-based sensors that exhibit fluorescence upon binding small-molecule fluorophores in living cells. Current fluorogenic RNA:fluorophore complexes typically emit visible fluorescence. However, it is challenging to develop fluorogenic RNA with near-infrared (NIR) fluorescence for in vivo imaging and sensing studies.

View Article and Find Full Text PDF

Rapid on-site colorimetric detection of arsenic(V) by NH-MIL-88(Fe) nanozymes-based ultraviolet-visible spectroscopic and smartphone-assisted sensing platforms.

Anal Chim Acta

January 2025

College of Resources and Environment, Southwest University, Chongqing, 400716, China; Key Laboratory of Biomedical Analytics (Southwest University), Chongqing Science and Technology Bureau, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, China. Electronic address:

Background: Because arsenate (As(V)) is a highly toxic pollutant, timely on-site monitoring of its concentration is crucial for mitigating potential environmental and health hazards. Traditional on-site detection methods for As(V) often face limitations of long response time and low sensitivity. Nanozymes are nanomaterials that exhibit enzyme-like catalytic activity.

View Article and Find Full Text PDF

Magnetic optimizing surface-enhanced Raman scattering (SERS) strategy of detection and in-situ monitoring of photodegradation of Benzo[a]pyrene in water.

Anal Chim Acta

January 2025

The Education Ministry Key Laboratory of Resource Chemistry, Joint International Research Laboratory of Resource Chemistry, Ministry of Education, Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Municipal Education Committee Key Laboratory of Molecular Imaging Probes and Sensors, Shanghai Frontiers Science Center of Biomimetic Catalysis and College of chemistry and materials science, School of Environmental and Geographical Sciences. Shanghai Normal University, Shanghai, 200234, People's Republic of China. Electronic address:

Background: Polycyclic aromatic hydrocarbons (PAHs) are one of the most dangerous persistent organic pollutants in the environment. Due to the discharge of chemical plants and domestic water, the existence of PAHs in sea water and lake water is harmful to human health. A method for rapid detection and removal of PAHs in water needs to be developed.

View Article and Find Full Text PDF

Photocurrent Generation by Plant Light-Harvesting Complexes is Enhanced by Lipid-Linked Chromophores in a Self-Assembled Lipid Membrane.

J Phys Chem B

January 2025

Department of Life Science and Applied Chemistry, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan.

The light-harvesting pigment-protein complex II (LHCII) from plants can be used as a component for biohybrid photovoltaic devices, acting as a photosensitizer to increase the photocurrent generated when devices are illuminated with sunlight. LHCII is effective at photon absorption in the red and blue regions of the visible spectrum, however, it has low absorption in the green region (550-650 nm). Previous studies have shown that synthetic chromophores can be used to fill this spectral gap and transfer additional energy to LHCII, but it was uncertain whether this would translate into an improved performance for photovoltaics.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!