scholarly journals Coherent X-ray Imaging: Bridging the Gap between Atomic and Micro-scale Investigations

2014 ◽  
Vol 68 (1) ◽  
pp. 66-72 ◽  
Author(s):  
Marco Stampanoni ◽  
Andreas Menzel ◽  
Ben Watts ◽  
Kevin S. Mader ◽  
Oliver Bunk
Keyword(s):  
X Ray ◽  
Micro Scale ◽  
X Ray Imaging

Potential of combined neutron and X-ray imaging to quantify local carbon contents in soil

2020 ◽  
Author(s):  
Genoveva Burca ◽  
Stephen Hillier ◽  
Pawala Ariyathilaka ◽  
Jumpei Fukumasu ◽  
Anke Herrmann ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Clay Content ◽  
Pore Network ◽  
Soil Samples ◽  
X Rays ◽  
X Ray ◽  
3 Dimensional ◽  
Micro Scale ◽  
X Ray Imaging ◽  
Neutron Attenuation

<p>Soil organic carbon (SOC) is of key importance for soil functioning. It strongly impacts soil fertility, greenhouse gas emissions, nutrient retention, and contaminant degradation. The soil pore network determines how oxygen, water and nutrients are transported and exchanged in soil, and the architecture of the soil is therefore equally fundamental to soil functions. For a thorough understanding of the microbial habitat, the soil pore network architecture needs to be evaluated alongside with the spatial distribution of SOC, but the challenge ahead is the 3-D visualization of organic carbon at the micro-scale. At present, such visualizations are undertaken using staining agents, but their non-specific binding to other features in the soil aggravates evaluation of organic carbon at the micro-scale.</p><p>In the present study, we investigated the potential and limitations of using joint white-beam neutron and X-ray imaging for mapping the 3-dimensional organic carbon distribution in soil. This approach is viable because neutron and X-ray beams have complementary attenuation properties. Soil minerals consist to a large part of silicon and aluminium, elements which are relatively translucent to neutrons but attenuate X-rays. In contrast, attenuation of neutrons is strong for hydrogen, which is abundant in SOC, while hydrogen barely attenuates X-rays. When considering dried soil samples, the complementary attenuation for neutrons and X-rays may be used to quantify the fractions of air, SOC and minerals for any imaged voxel in a bi-modal 3-dimensional image, i.e. a combined neutron and X-ray image.</p><p>We collected neutron data at the IMAT beamline at the ISIS facility and X-ray data at the I12 beamline at the Diamond Light source, both located within the Rutherford Appleton Laboratory, Harwell, UK. The neutron image clearly showed variations in neutron attenuation within soil aggregates at approximately constant X-ray attenuations. This indicates a constant bulk density with varying organic matter and/or mineralogy. For samples with identical mineral composition, neutron attenuation data of sieved and repacked soil samples exhibited a large coefficient of determination (R<sup>2</sup>) in a regression between volumetric SOC content and neutron attenuation (0.9). Even larger R<sup>2</sup> (0.93) were obtained when the volumetric clay content was also included into the regression. However, when comparing soil samples with different mineralogy, R<sup>2</sup> dropped to 0.24 and 0.37, depending whether the clay content was considered or not. To improve the method, it is necessary to include specifics of the soil mineralogy. Here, analysing the time-of-flight neutron attenuation data collected at the IMAT beamline will provide further insights. In summary, our approach yielded promising results. We anticipate that quantitative 3-D imaging of organic carbon contents in soil will be possible in the near future.</p>

Hollow microcapsules for sensing micro-scale flow motion in X-ray imaging method

2008 ◽  
Vol 6 (3) ◽  
pp. 419-424 ◽  
Author(s):  
Guk Bae Kim ◽  
Nam Yun Lim ◽  
Sang Joon Lee
Keyword(s):  
Imaging Method ◽  
X Ray ◽  
Micro Scale ◽  
X Ray Imaging ◽  
Flow Motion

scholarly journals 4D micro-scale, phase-contrast X-ray imaging and computed tomography of HMX-based polymer-bonded explosives during thermal runaway

2021 ◽  
Vol 226 ◽  
pp. 478-489
Author(s):  
G.R. Parker ◽  
D.S. Eastwood ◽  
M. Storm ◽  
K. Vitharana ◽  
E.M. Heatwole ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Phase Contrast ◽  
Thermal Runaway ◽  
X Ray ◽  
Micro Scale ◽  
X Ray Imaging ◽  
Polymer Bonded Explosives

Defects of Platelet Function Recognized by X-Ray Imaging and Scanning Electron Microscopy

1985 ◽  
Vol 43 ◽  
pp. 610-613
Author(s):  
M.G. Baldini ◽  
S. Morinaga ◽  
D. Minasian ◽  
R. Feder ◽  
D. Sayre ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Cell Biology ◽  
Imaging Technique ◽  
Human Platelets ◽  
X Rays ◽  
X Ray ◽  
X Ray Imaging ◽  
Complex Phenomena ◽  
Scanning Electron

Contact X-ray imaging is presently developing as an important imaging technique in cell biology. Our recent studies on human platelets have demonstrated that the cytoskeleton of these cells contains photondense structures which can preferentially be imaged by soft X-ray imaging. Our present research has dealt with platelet activation, i.e., the complex phenomena which precede platelet appregation and are associated with profound changes in platelet cytoskeleton. Human platelets suspended in plasma were used. Whole cell mounts were fixed and dehydrated, then exposed to a stationary source of soft X-rays as previously described. Developed replicas and respective grids were studied by scanning electron microscopy (SEM).

Designing high-resolution slow scan CCD-based TEM camera systems

1992 ◽  
Vol 50 (2) ◽  
pp. 946-947
Author(s):  
James F. Mancuso ◽  
William B. Maxwell ◽  
Russell E. Camp ◽  
Mark H. Ellisman
Keyword(s):  
Fiber Optics ◽  
Ccd Camera ◽  
High Energy ◽  
Phosphor Layer ◽  
X Ray ◽  
Light Production ◽  
Camera Systems ◽  
X Ray Imaging ◽  
Electron Image ◽  
Scintillating Fiber

The imaging requirements for 1000 line CCD camera systems include resolution, sensitivity, and field of view. In electronic camera systems these characteristics are determined primarily by the performance of the electro-optic interface. This component converts the electron image into a light image which is ultimately received by a camera sensor.Light production in the interface occurs when high energy electrons strike a phosphor or scintillator. Resolution is limited by electron scattering and absorption. For a constant resolution, more energy deposition occurs in denser phosphors (Figure 1). In this respect, high density x-ray phosphors such as Gd2O2S are better than ZnS based cathode ray tube phosphors. Scintillating fiber optics can be used instead of a discrete phosphor layer. The resolution of scintillating fiber optics that are used in x-ray imaging exceed 20 1p/mm and can be made very large. An example of a digital TEM image using a scintillating fiber optic plate is shown in Figure 2.

Ionic homeostasis and subcellular element compartmentation

1990 ◽  
Vol 48 (2) ◽  
pp. 150-151
Author(s):  
Ann LeFurgey ◽  
Peter Ingram ◽  
J.J. Blum ◽  
M.C. Carney ◽  
L.A. Hawkey ◽  
...  
Keyword(s):  
Leishmania Major ◽  
Ionic Homeostasis ◽  
X Ray ◽  
Functional Studies ◽  
Cell Compartments ◽  
X Ray Imaging ◽  
Resolution Electron ◽  
Multiple Cell ◽  
Role Of Zn

Subcellular compartments commonly identified and analyzed by high resolution electron probe x-ray microanalysis (EPXMA) include mitochondria, cytoplasm and endoplasmic or sarcoplasmic reticulum. These organelles and cell regions are of primary importance in regulation of cell ionic homeostasis. Correlative structural-functional studies, based on the static probe method of EPXMA combined with biochemical and electrophysiological techniques, have focused on the role of these organelles, for example, in maintaining cell calcium homeostasis or in control of excitation-contraction coupling. New methods of real time quantitative x-ray imaging permit simultaneous examination of multiple cell compartments, especially those areas for which both membrane transport properties and element content are less well defined, e.g. nuclei including euchromatin and heterochromatin, lysosomes, mucous granules, storage vacuoles, microvilli. Investigations currently in progress have examined the role of Zn-containing polyphosphate vacuoles in the metabolism of Leishmania major, the distribution of Na, K, S and other elements during anoxia in kidney cell nuclel and lysosomes; the content and distribution of S and Ca in mucous granules of cystic fibrosis (CF) nasal epithelia; the uptake of cationic probes by mltochondria in cultured heart ceils; and the junctional sarcoplasmic retlculum (JSR) in frog skeletal muscle.

Dynamic X-ray imaging of the penetration of boron carbide

2000 ◽  
Vol 10 (PR9) ◽  
pp. Pr9-583-Pr9-588 ◽  
Author(s):  
W. A. Gooch ◽  
M. S. Burkins ◽  
G. Hauver ◽  
P. Netherwood ◽  
R. Benck
Keyword(s):  
Boron Carbide ◽  
X Ray ◽  
X Ray Imaging

X-Ray Imaging

2020 ◽  
Author(s):  
Keyword(s):  
X Ray ◽  
X Ray Imaging
Sign in / Sign up

Export Citation Format

Share Document