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1. Hysteretic Three-State Redox Interconversion among Zigzag Bisquinodimethanes with Non-fused Benzene Rings and Twisted Tetra-/Dications with [5]/[3]Acenes Exhibiting Near-Infrared Absorptions

Author:
Ishigaki, Yusuke; Harimoto, Takashi; Sugawara, Kazuma; Suzuki, Takanori
Source:
Journal of the American Chemical Society 2021 v.143 no.9 pp. 3306-3311
ISSN:
1520-5126
Subject:
X-radiation,   etc   ; anthracenes; benzene; oxidation;     Show all 4 Subjects
Abstract:
... Octaaryl-substituted bisquinodimethanes (BQDs) with a zigzag structure were designed as redox-switchable molecules that undergo four-electron oxidation to produce tetracationic pentacenes with a doubly twisted structure. In contrast to one-stage four-electron oxidation of BQDs, stepwise two-electron reduction of tetracationic pentacenes occurs to give dicationic anthracenes and then the original B ...
DOI:
10.1021/jacs.1c00189

2. Quantitative Reconstruction of Polychromatic X-ray Fluorescence Computed Tomography Using Transmission Tomography

Author:
Gao, Bo; Laforce, Brecht; Vincze, Laszlo; Hoorebeke, Luc Van; Boone, Matthieu N.
Source:
Analytical chemistry 2021 v.93 no.4 pp. 2082-2089
ISSN:
1520-6882
Subject:
X-radiation,   etc   ; analytical chemistry; fluorescence;     Show all 3 Subjects
Abstract:
... Through measuring the intensity of the fluorescence X-rays emitted by the elements of interest, X-ray fluorescence computed tomography (XFCT) is capable of mapping the elemental distribution inside an object without destructively sectioning it. With the recent advances in XFCT utilizing polychromatic microfocus X-ray sources, it is expected that the popularity of such imaging modality will rise fu ...
DOI:
10.1021/acs.analchem.0c03828

3. Iodinated trihalomethanes formation in iopamidol-contained water during ferrate/chlor(am)ination treatment

Author:
Li, Mian; Zhang, Tian-Yang; Xu, Bin; Hu, Chen-Yan; Dong, Zheng-Yu; Wang, Zhen; Tang, Yu-Lin; Yu, Shui-Li; Pan, Yang; Xian, Qiming
Source:
Chemosphere 2021 v.272 pp. 129568
ISSN:
0045-6535
Subject:
X-radiation,   etc   ; chlorination; disinfection; iodine; pH; toxicity;     Show all 6 Subjects
Abstract:
... Iopamidol is a commonly used iodinated X-ray contrast media in medical field, and its residue in water can react with disinfectants to form highly toxic iodinated disinfection by-products (I-DBPs). This study investigated the degradation of iopamidol and formation of DBPs, especially iodinated trihalomethanes (I-THMs), during ferrate (Fe(VI)) pre-oxidation and subsequent chlor(am)ination under raw ...
DOI:
10.1016/j.chemosphere.2021.129568

4. Core growth of detonation nanodiamonds under high-pressure annealing

Author:
Bogdanov, Denis; Bogdanov, Alexander; Plotnikov, Vladimir; Makarov, Sergey; Yelisseyev, Alexander; Chepurov, Aleksei
Source:
RSC advances 2021 v.11 no.21 pp. 12961-12970
ISSN:
2046-2069
Subject:
X-radiation,   etc   ; gasification; graphene; hardness; nanodiamonds;     Show all 5 Subjects
Abstract:
... The present paper reports the results of a study of the X-ray and Raman spectra of detonation nanodiamonds after high-pressure–high-temperature (HPHT) annealing at different temperatures. The experiments were carried out using a multi-anvil high-pressure apparatus of the “split-sphere” type (BARS) at 5 GPa and 1100–1500 °C. It was found that HPHT annealing at 1500 °C led to the growth of nanodiamo ...
DOI:
10.1039/d1ra00270h

5. In-situ X-ray fluorescence to investigate iodide diffusion in opalinus clay: Demonstration of a novel experimental approach

Author:
Jaquenoud, Max; Elam, William T.; Grundl, Tim; Gimmi, Thomas; Jakob, Andreas; Schefer, Senecio; Cloet, Veerle; De Cannière, Pierre; Van Loon, Luc R.; Leupin, Olivier X.
Source:
Chemosphere 2021 v.269 pp. 128674
ISSN:
0045-6535
Subject:
X-radiation,   etc   ; clay; data collection; fluorescence; iodides;     Show all 5 Subjects
Abstract:
... During the last two decades, the Mont Terri rock laboratory has hosted an extensive experimental research campaign focusing on improving our understanding of radionuclide transport within Opalinus Clay. The latest diffusion experiment, the Diffusion and Retention experiment B (DR-B) has been designed based on an entirely different concept compared to all predecessor experiments. With its novel exp ...
DOI:
10.1016/j.chemosphere.2020.128674

6. Judd–Ofelt parameters and X-ray irradiation results of MNb₂O₆:Eu³⁺ (M = Sr, Cd, Ni) phosphors synthesized via a molten salt method

Author:
İlhan, Mustafa; Ekmekçi, Mete Kaan; Keskin, İlker Çetin
Source:
RSC advances 2021 v.11 no.18 pp. 10451-10462
ISSN:
2046-2069
Subject:
X-radiation,   etc   ; ceramics; irradiation; photoluminescence; temperature;     Show all 5 Subjects
Abstract:
... Trivalent Eu-activated MNb₂O₆ (M = Sr, Cd, Ni) ceramic phosphors were produced using the molten salt route, which involves a low sintering temperature and provides improved homogeneity. The photoluminescence (PL) and radioluminescence (RL) spectra of phosphors exhibited characteristic Eu³⁺ emissions with ⁵F₀ → ⁷Fⱼ transitions, and strong peaks occurred at the ⁵D₀ → ⁷F₂ transition. The PL and RL em ...
DOI:
10.1039/d0ra10834k

7. Island formation of Er(trensal) single-ion magnets on graphene observed on the micrometer scale

Author:
Dreiser, Jan; Wäckerlin, Christian; Buzzi, Michele; Pedersen, Kasper S.; Bendix, Jesper
Source:
RSC advances 2021 v.11 no.16 pp. 9421-9425
ISSN:
2046-2069
Subject:
X-radiation,   etc   ; electron microscopy; erbium; graphene;     Show all 4 Subjects
Abstract:
... We have studied the morphology of Er(trensal) single-ion molecular magnets adsorbed on graphene/Ru(0001) using X-ray photoemission electron microscopy (X-PEEM). By exploiting the elemental contrast at the erbium M₅ edge we observe the formation of molecular islands of homogeneous height with a lateral size of several micrometers. The graphene/Ru(0001) substrate exhibits two different signal levels ...
DOI:
10.1039/d1ra00783a

8. Mineralogical phase transformation of Fe containing sphalerite at acidic environments in the presence of Cu2+

Author:
Zhang, Yisheng; Zhao, Hongbo; Meng, Xiaoyu; Ou, Pengfei; Lv, Xin; Zhang, Luyuan; Liu, Lixin; Chen, Fashang; Qiu, Guanzhou
Source:
Journal of hazardous materials 2021 v.403 pp. 124058
ISSN:
0304-3894
Subject:
X-radiation,   etc   ; drainage; pH; phase transition; zinc;     Show all 5 Subjects
Abstract:
... Dissolution of the exposed sphalerite (marmatite) in abandoned mining sites and tailings may exacerbate acid and metalliferous drainage (AMD) hazards. Cupric ions are inevitable ions in AMD systems but its action mechanism on the dissolution of sphalerite is still unclear. In this work, the possible phase transition from sphalerite to chalcopyrite is firstly discovered in acidic cupric ions soluti ...
DOI:
10.1016/j.jhazmat.2020.124058

9. Single-crystal X-ray structure determinations of vardenafil, vardenafil dihydrate, vardenafil monohydrochloride trihydrate and vardenafil dihydrochloride hexahydrate

Author:
Wu, Dedong; Atassi, Faraj
Source:
Zeitschrift für Naturforschung 2021 v.76 no.1 pp. 45-53
ISSN:
1865-7117
Subject:
X-radiation,   etc   ; X-ray diffraction; crystal structure;     Show all 3 Subjects
Abstract:
... The crystal and molecular structures of vardenafil (free, unprotonated base), vardenafil dihydrate and the hydrochloride salts, vardenafil monohydrochloride trihydrate and vardenafil dihydrochloride hexahydrate, were determined by single-crystal X-ray diffraction. The crystal structure of vardenafil monohydrochloride trihydrate is in good agreement with the published crystal structure obtained by ...
DOI:
10.1515/znb-2020-0083

10. Pore-Scale X-ray Imaging of Wetting Alteration and Oil Redistribution during Low-Salinity Flooding of Berea Sandstone

Author:
Andrews, Edward; Muggeridge, Ann; Garfi, Gaetano; Jones, Alistair; Krevor, Samuel
Source:
Energy & fuels 2021 v.35 no.2 pp. 1197-1207
ISSN:
1520-5029
Subject:
X-radiation,   etc   ; energy; oils; petroleum; salinity; sandstone;     Show all 6 Subjects
Abstract:
... Observations over a range of scales show that lowering the salinity of injected water can alter the wetting state of a rock, making it more water-wet. However, there remains a poor understanding of how this alteration affects the distribution of fluids over the pore and pore-network scale and how this wetting alteration leads to oil recovery. In this work, we observe how oil and brine redistribute ...
DOI:
10.1021/acs.energyfuels.0c03299

11. In operando visualization of electrolyte stratification dynamics in lead-acid battery using phase-contrast X-ray imaging

Author:
Takamatsu, Daiko; Hirano, Tatsumi; Yoneyama, Akio; Kimura, Takayuki; Harada, Motoko; Terada, Masayuki; Okoshi, Tetsuro
Source:
Chemical communications 2020 v.56 no.66 pp. 9553-9556
ISSN:
1364-548X
Subject:
X-radiation,   etc   ; batteries; electrolytes;     Show all 3 Subjects
Abstract:
... An understanding of electrolyte stratification behaviours in lead-acid battery electrolytes during battery operation is important for optimal operation and design of lead-acid batteries for vehicle applications. In this paper, we present an in operando phase-contrast X-ray imaging technique for quantitatively visualizing electrolyte stratification dynamics that arise in electrolytes during battery ...
DOI:
10.1039/d0cc03592k

12. Superhydrophobic self-similar nonwoven-titanate nanostructured materials

Author:
Sharma, Sumit; Rawal, Amit; Tóth, Ildikó Y; Vásárhelyi, Lívia; Kozma, Gábor; Kukovecz, Ákos; Jee, Shyam; Ayaydin, Ferhan
Source:
Journal of colloid and interface science 2021 v.598 pp. 93-103
ISSN:
0021-9797
Subject:
X-radiation,   etc   ; air; hydrophobicity; micro-computed tomography; nanowires; wettability;     Show all 6 Subjects
Abstract:
... Self-similarity is a scale-invariant irregularity that can assist in designing a robust superhydrophobic material. A combinatorial design strategy involving self-similarity and dual-length scale can be employed to create a new library of a doubly re-entrant, disordered, and porous network of superhydrophobic materials. Asymmetric wettability can be engineered in nonwoven materials by rendering the ...
DOI:
10.1016/j.jcis.2021.03.045

13. Removal of humic acid and Cr(Ⅵ) from water using ZnO–30N-zeolite

Author:
Wang, Lingling; Dionysiou, Dionysios D.; Lin, Jianming; Huang, Yuxian; Xie, Xiaolan
Source:
Chemosphere 2021 v.279 pp. 130491
ISSN:
0045-6535
Subject:
X-radiation,   etc   ; chromium; humic acids; pollutants; water purification;     Show all 5 Subjects
Abstract:
... The mutual influence of humic acid and Cr(Ⅵ) on water purification using ZnO–30N-zeolite was investigated in the laboratory. The removal of humic acid by ZnO–30N-zeolite with both pollutants present reached 90% in 5 min. With humic acid alone, more than one day was required to reach the same level of removal. Synergy between humic acid and chromium was thus demonstrated in their removal process by ...
DOI:
10.1016/j.chemosphere.2021.130491

14. Proximal sensor-enhanced soil mapping in complex soil-landscape areas of Brazil

Author:
SILVA, Sérgio H.G.; WEINDORF, David C.; FARIA, Wilson M.; PINTO, Leandro C.; MENEZES, Michele D.; GUILHERME, Luiz R.G.; CURI, Nilton
Source:
Pedosphere 2021 v.31 no.4 pp. 615-626
ISSN:
1002-0160
Subject:
X-radiation,   etc   ; algorithms; fluorescence; landscapes; magnetic susceptibility; prediction; Brazil;     Show all 7 Subjects
Abstract:
... Portable X-ray fluorescence (pXRF) spectrometry and magnetic susceptibility (MS) via magnetometer have been increasingly used with terrain variables for digital soil mapping. However, this methodology is still emerging in many countries with tropical soils. The objective of this study was to use proximal soil sensor data associated with terrain variables at varying spatial resolutions to predict s ...
DOI:
10.1016/S1002-0160(21)60007-3

15. Diffracted X-ray blinking measurements of interleukin 15 receptors in the inner/outer membrane of living NK cells

Author:
Chang, Jaewon; Baek, Yonugseok; Lee, Injee; Sekiguchi, Hiroshi; Ichiyanagi, Kouhei; Mio, Kazuhiro; Nozawa, Shunsuke; Fukaya, Ryo; Adachi, Shin-ichi; Kuramochi, Masahiro; Sasaki, Yuji C.
Source:
Biochemical and biophysical research communications 2021 v.556 pp. 53-58
ISSN:
0006-291X
Subject:
X-radiation,   etc   ; interleukin-15; interleukin-2; research; transmembrane proteins;     Show all 5 Subjects
Abstract:
... Interleukin 15 receptor (IL-15R) is a transmembrane signalling protein consisting of 3 subsets: α, β (IL-15Rβ), and γ (γc). IL-2 and IL-15 share the signalling domains IL-15Rβ and γc, although they bind to intrinsic α-subsets and non-signalling domains. Additionally, IL-2 and IL-15 play different roles; therefore, there have been many observations of the dynamic behaviours of IL-15R, which are lin ...
DOI:
10.1016/j.bbrc.2021.03.144

16. Core-scale investigation of the effect of heterogeneity on the dynamics of residual and dissolution trapping of carbon dioxide

Author:
Kim, Kue-Young; Kim, Minji; Oh, Junho
Source:
Journal of hydrology 2021 v.596 pp. 126109
ISSN:
0022-1694
Subject:
X-radiation,   etc   ; carbon dioxide; drainage; energy; imbibition; remediation;     Show all 6 Subjects
Abstract:
... Geologic heterogeneity, which commonly exists in target reservoirs for CO₂ sequestration, has a significant effect on CO₂ trapping. In this study, we performed Darcy-scale multiphase flow experiments on a heterogeneous rock with in-situ imaging techniques to obtain X-ray images of CO₂ saturation during both drainage and imbibition. Residual trapping was assessed using the initial-residual characte ...
DOI:
10.1016/j.jhydrol.2021.126109

17. Towards accurate and precise positions of hydrogen atoms bonded to heavy metal atoms

Author:
Woińska, Magdalena; Chodkiewicz, Michał L.; Woźniak, Krzysztof
Source:
Chemical communications 2021 v.57 no.30 pp. 3652-3655
ISSN:
1364-548X
Subject:
X-radiation,   etc   ; X-ray diffraction; heavy metals; hydrides; hydrogen; neutrons;     Show all 6 Subjects
Abstract:
... A comparison of five X-ray structures of transition-metal-bound hydride complexes, successfully refined using Hirshfeld Atom Refinement (HAR) against low resolution X-ray diffraction data (including the positions and ADPs of all hydrogen atoms), with neutron structures shows that using aspherical atomic scattering factors instead of spherical ones results in systematic elongation of metal–hydrogen ...
DOI:
10.1039/d0cc07661a

18. Elemental concentration of tomato paste and respective packages through particle-induced X-ray emission

Author:
Debastiani, Rafaela; Iochims dos Santos, Carla Eliete; Maciel Ramos, Mateus; Sobrosa Souza, Vanessa; Yoneama, Maria Lucia; Amaral, Livio; Ferraz Dias, Johnny
Source:
Journal of food composition and analysis 2021 v.97 pp. 103770
ISSN:
0889-1575
Subject:
X-radiation,   etc   ; cardboard; food composition; storage time; tomato paste; tomatoes;     Show all 6 Subjects
Abstract:
... The elemental concentrations of three brands of Brazilian tomato paste packed in cans and Tetra Pak® cardboard boxes were determined through the Particle-Induced X-ray Emission (PIXE) technique. The elements Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, Mn, Fe, Ni, Cu, Zn, Br and Rb were identified in the tomato pastes. The metallic cannisters are characterized primarily by the presence of Fe and Sn, while ...
DOI:
10.1016/j.jfca.2020.103770

19. Recapitulating the Binding Affinity of Nrf2 for KEAP1 in a Cyclic Heptapeptide, Guided by NMR, X-ray Crystallography, and Machine Learning

Author:
Ortet, Paula C.; Muellers, Samantha N.; Viarengo-Baker, Lauren A.; Streu, Kristina; Szymczyna, Blair R.; Beeler, Aaron B.; Allen, Karen N.; Whitty, Adrian
Source:
Journal of the American Chemical Society 2021 v.143 no.10 pp. 3779-3793
ISSN:
1520-5126
Subject:
X-radiation,   etc   ; X-ray diffraction; geometry; hydrophobicity; ligands; peptides; proline;     Show all 7 Subjects
Abstract:
... Macrocycles, including macrocyclic peptides, have shown promise for targeting challenging protein–protein interactions (PPIs). One PPI of high interest is between Kelch-like ECH-Associated Protein-1 (KEAP1) and Nuclear Factor (Erythroid-derived 2)-like 2 (Nrf2). Guided by X-ray crystallography, NMR, modeling, and machine learning, we show that the full 20 nM binding affinity of Nrf2 for KEAP1 can ...
DOI:
10.1021/jacs.0c09799

20. Synthesis of 25X-BOMes and 25X-NBOHs (X = H, I, Br) for pharmacological studies and as reference standards for forensic purposes

Author:
Alves de Barros, Wellington; Queiroz, Marcelo Pereira; da Silva Neto, Leonardo; Borges, Graziele Martins; Martins, Felipe Terra; de Fátima, Ângelo
Source:
Tetrahedron letters 2021 v.66 pp. 152804
ISSN:
0040-4039
Subject:
X-radiation,   etc   ; forensic sciences; hydroxybenzaldehyde; reference standards; synthesis;     Show all 5 Subjects
Abstract:
... An expeditious method is reported for the synthesis of three NBOHs (25H-, 25I- and 25B-NBOH; 9–38% overall yield) and three NBOMes (25H-, 25I- and 25B-NBOMe; 7–33% overall yield) from salicylaldehyde and 2-methoxyaldehyde, respectively. The X-ray structures of 25H-, 25I- and 25B-NBOH.HCl were also determined. Our approach should provide a general entry for preparing such a class of substances for ...
DOI:
10.1016/j.tetlet.2020.152804