Performance assessment of active vs passive pixel x‐ray angiography detector systems using a bias‐corrected channelized Hotelling observer and adult patient‐equivalent experimental conditions

The ultimate sensitivity of microchemical analysis using x-ray emission rests in selecting those experimental conditions which will maximize the measured peak-to-background (P/B) ratio. This paper presents the results of calculations aimed at determining the influence of incident beam energy, detector/specimen geometry and specimen composition on the P/B ratio for ideally thin samples (i.e., the effects of scattering and absorption are considered negligible). As such it is assumed that the complications resulting from system peaks, bremsstrahlung fluorescence, electron tails and specimen contamination have been eliminated and that one needs only to consider the physics of the generation/emission process.The number of characteristic x-ray photons (Ip) emitted from a thin foil of thickness dt into the solid angle dΩ is given by the well-known equation

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Zeolite NaP1 Functionalization for the Sorption of Metal Complexes with Biodegradable N-(1,2-dicarboxyethyl)-D,L-aspartic Acid

Materials ◽

10.3390/ma14102518 ◽

2021 ◽

Vol 14 (10) ◽

pp. 2518

Author(s):

Dorota Kołodyńska ◽

Yongming Ju ◽

Małgorzata Franus ◽

Wojciech Franus

Keyword(s):

Experimental Data ◽

Aspartic Acid ◽

Ph Value ◽

Complexing Agents ◽

X Ray Diffraction ◽

Experimental Conditions ◽

Modified Zeolite ◽

X Ray ◽

Slow Release Fertilizers ◽

Pseudo Second Order

The possibility of application of chitosan-modified zeolite as sorbent for Cu(II), Zn(II), Mn(II), and Fe(III) ions and their mixtures in the presence of N-(1,2-dicarboxyethyl)-D,L-aspartic acid, IDHA) under different experimental conditions were investigated. Chitosan-modified zeolite belongs to the group of biodegradable complexing agents used in fertilizer production. NaP1CS as a carrier forms a barrier to the spontaneous release of the fertilizer into soil. The obtained materials were characterized by Fourier transform infrared spectroscopy (FTIR); surface area determination (ASAP); scanning electron microscopy (SEM-EDS); X-ray fluorescence (XRF); X-ray diffraction (XRD); and carbon, hydrogen, and nitrogen (CHN), as well as thermogravimetric (TGA) methods. The concentrations of Cu(II), Zn(II), Mn(II), and Fe(III) complexes with IDHA varied from 5–20 mg/dm3 for Cu(II), 10–40 mg/dm3 for Fe(III), 20–80 mg/dm3 for Mn(II), and 10–40 mg/dm3 for Zn(II), respectively; pH value (3–6), time (1–120 min), and temperature (293–333 K) on the sorption efficiency were tested. The Langmuir, Freundlich, Dubinin–Radushkevich, and Temkin adsorption models were applied to describe experimental data. The pH 5 proved to be appropriate for adsorption. The pseudo-second order and Langmuir models were consistent with the experimental data. The thermodynamic parameters indicate that adsorption is spontaneous and endothermic. The highest desorption percentage was achieved using the HCl solution, therefore, proving that method can be used to design slow-release fertilizers.

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An anti-settling sample delivery instrument for serial femtosecond crystallography

Journal of Applied Crystallography ◽

10.1107/s0021889812024557 ◽

2012 ◽

Vol 45 (4) ◽

pp. 674-678 ◽

Cited By ~ 42

Author(s):

Lukas Lomb ◽

Jan Steinbrener ◽

Sadia Bari ◽

Daniel Beisel ◽

Daniel Berndt ◽

...

Keyword(s):

Constant Flow ◽

Syringe Pump ◽

Experimental Conditions ◽

Flow Rates ◽

X Ray ◽

Constant Flow Rate ◽

Significant Impairment ◽

Working Principle ◽

After Hours ◽

Serial Femtosecond Crystallography

Serial femtosecond crystallography (SFX) using X-ray free-electron laser (FEL) sources has the potential to determine the structures of macromolecules beyond the limitation of radiation damage and without the need for crystals of sufficient size for conventional crystallography. In SFX, a liquid microjet is used to inject randomly oriented crystals suspended in their storage solution into the FEL beam. Settling of crystals in the reservoir prior to the injection has been found to complicate the data collection. This article details the development of an anti-settling sample delivery instrument based on a rotating syringe pump, capable of producing flow rates and liquid pressures necessary for the operation of the injector. The device has been used successfully with crystals of different proteins, with crystal sizes smaller than 20 µm. Even after hours of continuous operation, no significant impairment of the experiments due to sample settling was observed. This article describes the working principle of the instrument and sets it in context with regard to the experimental conditions used for SFX. Hit rates for longer measuring periods are compared with and without the instrument operating. Two versions of the instrument have been developed, which both deliver sample at a constant flow rate but which differ in their minimum liquid flow rates and maximum pressures.

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Photocatalytic Degradation of Methylene Blue over Co-Ag3VO4 under Visible Light Irradiation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.335-336.1385 ◽

2011 ◽

Vol 335-336 ◽

pp. 1385-1390 ◽

Cited By ~ 1

Author(s):

Shuo Wiei Zhao ◽

Hui Xu ◽

Hua Ming Li ◽

Yuan Guo Xu

Keyword(s):

Methylene Blue ◽

Photocatalytic Activity ◽

Visible Light ◽

Visible Light Irradiation ◽

Absorption Edge ◽

Diffuse Reflectance Spectroscopy ◽

Dye Degradation ◽

Light Irradiation ◽

Experimental Conditions ◽

X Ray

In order to improve the photocatalytic activity, Co was successfully loaded into Ag3VO4 by using impregnation process. The samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS) and diffuse reflectance spectroscopy (DRS). The XRD and SEM–EDS analyses revealed that Co ion was dispersed on Ag3VO4. The DRS results indicated that the absorption edge of the Co–Ag3VO4 catalyst shifted to longer wavelength. The enhanced photocatalytic activity of Co–Ag3VO4 for Methylene Blue(MB) dye degradation under visible light irradiation was due to its wider absorption edge and higher separation rate of photo-generated electron and holes. In the experimental conditions, it is demonstrated that the MB was effectively degraded by more than 95% within 40 min when the Co–Ag3VO4 catalyst was calcined at 300°C with 1 wt.% Co content.

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Can a channelized Hotelling observer assess image quality in acquired mammographic images of an anthropomorphic breast phantom including image processing?

Medical Physics ◽

10.1002/mp.13342 ◽

2019 ◽

Vol 46 (2) ◽

pp. 714-725 ◽

Cited By ~ 1

Author(s):

C. Balta ◽

R. W. Bouwman ◽

I. Sechopoulos ◽

M. J. M. Broeders ◽

N. Karssemeijer ◽

...

Keyword(s):

Image Processing ◽

Image Quality ◽

Mammographic Images ◽

Hotelling Observer ◽

Breast Phantom ◽

Channelized Hotelling Observer

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Use of a channelized Hotelling observer to assess CT image quality and optimize dose reduction for iteratively reconstructed images

Journal of Medical Imaging ◽

10.1117/1.jmi.4.3.031213 ◽

2017 ◽

Vol 4 (03) ◽

pp. 1 ◽

Cited By ~ 3

Author(s):

Christopher P. Favazza ◽

Andrea Ferrero ◽

Lifeng Yu ◽

Shuai Leng ◽

Kyle L. McMillan

Keyword(s):

Image Quality ◽

Dose Reduction ◽

Ct Image ◽

Hotelling Observer ◽

Ct Image Quality ◽

Channelized Hotelling Observer

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Analysis of grape fruits and grape seed for their major , minor and trace elemental contact by XRF technique

Baghdad Science Journal ◽

10.21123/bsj.8.2.618-624 ◽

2011 ◽

Vol 8 (2) ◽

pp. 618-624

Author(s):

Baghdad Science Journal

Keyword(s):

Radiation Source ◽

Grape Seed ◽

Medical Studies ◽

Grape Seeds ◽

Experimental Conditions ◽

Experimental Procedure ◽

X Ray ◽

Minor Elements ◽

A Value ◽

Trace Elemental

Grapes and grape seeds are important samples employed for environmental medical studies . The air of this work was to identify and concentration calculation of the elements in grapes fruit and thier seeds by using X-Ray fluoresces technique (XRF) . Samples were collected from Abo Ghraib of Baghdad city ,the grape seeds were obtained from those samples . Both samples were taken under experimental procedure to obtain the sample which were ready for analysis . The samples were then submitted to experimental conditions using a radiation source and then samples were applied for counting analysis shows the elements Na , Mg , Al , Si , P , S , Cl , K , Ca , and Sr as major components of the samples. Fe , Sr , I , Ba and V were found an minor elements other elements Cr , Cu , Sn , Sb , Te gave a value of 5 – 10 ppm , Co , Ni , Rb , Ag ,Cd < 5 ppm for the samples of grape seeds . The analysis of grape seeds present Sr , Ca , K , Cl , S , Si , P as major components of the samples, and gave a values for Cr and Rb , Sn , Sb and Te (5 – 10 ppm) , while Co , Rb , Ni , Ag ,Cd (Less than 5 ppm) .

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