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https://www.readbyqxmd.com/read/29331822/synthesis-of-uio-66-oh-zirconium-metal-organic-framework-and-its-application-for-selective-extraction-and-trace-determination-of-thorium-in-water-samples-by-spectrophotometry
#1
Zahra Safaei Moghaddam, Massoud Kaykhaii, Mostafa Khajeh, Ali Reza Oveisi
In this study, a zirconium-based metal-organic framework (Zr-MOF), named UiO-66-OH, was synthesized by the solvo-thermal method and characterized by Fourier transform-infrared spectroscopy (FTIR), powder X-ray diffraction (PXRD), and scanning electron microscopy (SEM). This Zr-MOF was then employed as a sorbent for selective extraction and preconcentration of thorium ions after their complexation with 2‑(2,4‑dihydroxyphenyl)‑3,5,7‑trihydroxychromen‑4‑one (morin) from environmental water samples prior to its spectrophotometrical determination...
January 5, 2018: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/29298033/correction-to-mass-spectrometric-determination-of-uranium-and-thorium-in-high-radiopurity-polymers-using-ultra-low-background-electroformed-copper-crucibles-for-dry-ashing
#2
Isaac J Arnquist, Eric W Hoppe, Mary Bliss, Jay W Grate
No abstract text is available yet for this article.
January 3, 2018: Analytical Chemistry
https://www.readbyqxmd.com/read/29289303/determination-of-ultra-trace-level-of-232th-in-seawater-by-icp-sfms-after-matrix-separation-and-preconcentration
#3
Irena Wysocka, Emilia Vassileva
This article describes the development and validation of an analytical procedure for the matrix separation, preconcentration and determination of sub-ng kg-1 levels 232Th in a small volume (20 mL) of seawater samples. The matrix separation and Th preconcentration was carried out using a commercially available ion-chelation system seaFAST-pico. The acidified to pH < 2 seawater samples were mixed on-line with the ammonium acetate buffer (pH of 6.0 ± 0.2) before loading on the column containing resin with iminodiacetic and ethylenediaminetriacetic functional groups...
February 13, 2018: Analytica Chimica Acta
https://www.readbyqxmd.com/read/29288909/on-the-feasibility-of-determining-the-230th-activity-in-minerals-without-the-addition-of-a-th-radiotracer
#4
Mohammad Hosseinpour Khanmiri, Roman V Bogdanov
The necessity of measuring the radioactivity of the 230Тh nuclide arises when attempting to solve a number of geochemical or geochronological problems based on the effects of radioactive disequilibrium in the 238U series. It is the authors' opinion that the use of the traditional α- and β-emitters of thorium as a radiotracer in order to determine the activity of 230Тh leads to various inconveniences and difficulties of a technical nature. The authors recommend using the 234Тh isotope contained in the study sample as the simplest and most natural way of measuring the chemical yield of the targeted nuclide (230Тh)...
December 20, 2017: Applied Radiation and Isotopes
https://www.readbyqxmd.com/read/29232498/electron-precise-actinide-pnictide-an-pn-bonds-spanning-non-metal-metalloid-and-metal-combinations-an-u-th-pn-p-as-sb-bi
#5
Stephen Liddle, Thomas Rookes, Elizabeth Wildman, Gabor Balazs, Benedict Gardner, Ashley Wooles, Matthew Gregson, Floriana Tuna, Manfred Scheer
We report the synthesis and characterisation of the compounds [An(TrenDMBS){Pn(SiMe3)2}] and [An(TrenTIPS){Pn(SiMe3)2}] [TrenDMBS = N(CH2CH2NSiMe2But)3, An = U, Pn = P, As, Sb, Bi; An = Th, Pn = P, As; TrenTIPS = N(CH2CH2NSiPri3)3, An = U, Pn = P, As, Sb; An = Th, Pn = P, As, Sb]. The U-Sb and Th-Sb moieties are unprecedented examples of any kind of An-Sb molecular bond, and the U-Bi bond is the first electron-precise one. The Th-Bi combination was too unstable to isolate, underscoring the fragility of these linkages...
December 12, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/29211691/long-term-monitoring-of-water-treatment-technology-designed-for-radium-removal-removal-efficiencies-and-norm-formation
#6
Liie Hill, Siiri Suursoo, Madis Kiisk, Alar Jantsikene, Nele Nilb, Rein Munter, Enn Realo, Rein Koch, Kaisa Putk, Maria Leier, Taavi Vaasma, Kadri Isakar
A drinking water treatment plant in Viimsi, Estonia, was monitored over three years for iron, manganese, radium-226, radium-228, as well as their daughter nuclides, in order to determine the efficiency of the treatment process, gain an insight into the removal mechanisms and interactions between radium, iron, and manganese, and assess the overall longevity and performance of the technology along with the possible build-up of NORM in the treatment process. During the study, samples were collected from raw water, first and second stage filtrate, consumer water, backwash water and filter materials...
December 6, 2017: Journal of Radiological Protection: Official Journal of the Society for Radiological Protection
https://www.readbyqxmd.com/read/29206451/correction-to-understanding-the-scarcity-of-thorium-peroxide-clusters
#7
Shane S Galley, Cayla E Van Alstine, Laurent Maron, Thomas E Albrecht-Schmitt
No abstract text is available yet for this article.
December 5, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/29153973/airborn-gamma-ray-spectrometric-data-as-guide-for-probable-hydrocarbon-accumulations-at-al-laqitah-area-central-eastern-desert-of-egypt
#8
Ahmed A Nigm, Mohamed A S Youssef, Fatema M Abdelwahab
An exploration method has been developed to understand the relation between the radiometric measurements and the subsurface petroleum accumulations, where subtle anomalous patterns of radiation flux are detected over subsurface hydrocarbon basins. This technique is mainly based on utilizing the aerial gamma-ray spectral data in the prospecting for petroleum in stratigraphic and structural traps. Al-Laqitah area, Central Eastern Desert, Egypt, was selected to apply this method on its recorded aerial gamma-ray spectrometric survey data...
November 1, 2017: Applied Radiation and Isotopes
https://www.readbyqxmd.com/read/29153089/chromatographic-separation-of-the-theranostic-radionuclide-111-ag-from-a-proton-irradiated-thorium-matrix
#9
Tara Mastren, Valery Radchenko, Jonathan W Engle, John W Weidner, Allison Owens, Lance E Wyant, Roy Copping, Mark Brugh, F Meiring Nortier, Eva R Birnbaum, Kevin D John, Michael E Fassbender
Column chromatographic methods have been developed to separate no-carrier-added (111)Ag from proton irradiated thorium targets and associated fission products as an ancillary process to an existing (225)Ac separation design. Herein we report the separation of (111)Ag both prior and subsequent to (225)Ac recovery using CL resin, a solvent impregnated resin (SIR) that carries an organic solution of alkyl phosphine sulfides (R3P = S) and alkyl phosphine oxides (R3P = O). The recovery yield of (111)Ag was 93 ± 9% with a radiochemical purity of 99...
January 15, 2018: Analytica Chimica Acta
https://www.readbyqxmd.com/read/29150802/ion-imprinted-electrospun-nanofibers-of-chitosan-1-butyl-3-methylimidazolium-tetrafluoroborate-for-the-dynamic-expulsion-of-thorium-iv-ions-from-mimicked-effluents
#10
Prakash Macchindra Gore, Latika Khurana, Suhail Siddique, Anjana Panicker, Balasubramanian Kandasubramanian
The present study explores the innocuous, biocompatible, and extremely competent molecularly imprinted chitosan/RTIL electrospun nanofibers having average diameter of 30 nm for the expulsion of thorium (IV) ions from the mimicked effluent waste. The extended Flory-Huggins theory and three-dimensional molecular modeling have been effectively premeditated via Materials Studio software for enumerating the inter-miscibility and compatibility (Chi parameter (χ) = 1.019, mixing energy (Emix) = 0.603 kcal/mol) of the chitosan/RTIL (1-butyl-3-methylimidazolium tetrafluoroborate)...
November 17, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/29148745/influence-of-counter-cation-hydration-enthalpies-on-the-formation-of-molecular-complexes-a-thorium-nitrate-example
#11
Geng Bang Jin, Jian Lin, Shanna L Estes, Suntharalingam Skanthakumar, Lynda Soderholm
The influence of counter-cations (A(n+)) in directing the composition of monomeric metal-ligand (ML) complexes that precipitate from solution are often overlooked despite the wide usage of A(n+) in materials synthesis. Herein we describe a correlation between the composition of ML complexes and A(+) hydration enthalpies found for two related series of Th-nitrate molecular compounds obtained by evaporating acidic aqueous Th-nitrate solutions in the presence of A(+) counter-ions. Analyses of their chemical composition and solid-state structures demonstrate that A(+) not only affects the overall solid-state packing of the Th-nitrato complexes but also influences the composition of the Th-nitrato monomeric anions themselves...
November 17, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/29144747/structural-variability-of-4f-and-5f-thiocyanate-complexes-and-dissociation-of-uranium-iii-thiocyanate-bonds-with-increased-ionicity
#12
Saptarshi Biswas, Shuwen Ma, Stefano Nuzzo, Brendan Twamley, Andrew T Russell, James A Platts, František Hartl, Robert J Baker
A series of complexes [Et4N][Ln(NCS)4(H2O)4] (Ln = Pr, Tb, Dy, Ho, Yb) have been structurally characterized, all showing the same structure, namely a distorted square antiprismatic coordination geometry, and the Ln-O and Ln-N bond lengths following the expected lanthanide contraction. When the counterion is Cs(+), a different structural motif is observed and the eight-coordinate complex Cs5[Nd(NCS)8] isolated. The thorium compounds [Me4N]4[Th(NCS)7(NO3)] and [Me4N]4[Th(NCS)6(NO3)2] have been characterized, and high coordination numbers are also observed...
November 16, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/29137748/a-novel-synthesis-of-a-new-thorium-iv-metal-organic-framework-nanostructure-with-well-controllable-procedure-through-ultrasound-assisted-reverse-micelle-method
#13
Ghasem Sargazi, Daryoush Afzali, Ali Mostafavi
Reverse micelle (RM) and ultrasound assisted reverse micelle (UARM) were applied to the synthesis of novel thorium nanostructures as metal organic frameworks (MOFs). Characterization with different techniques showed that the Th-MOF sample synthesized by UARM method had higher thermal stability (354°C), smaller mean particle size (27nm), and larger surface area (2.02×10(3)m(2)/g). Besides, in this novel approach, the nucleation of crystals was found to carry out in a shorter time. The synthesis parameters of UARM method were designed by 2(k-1) factorial and the process control was systematically studied using analysis of variance (ANOVA) and response surface methodology (RSM)...
March 2018: Ultrasonics Sonochemistry
https://www.readbyqxmd.com/read/29129866/determination-of-trace-fission-products-associated-with-thorium-and-hcl-matrix-by-inductively-coupled-plasma-mass-spectrometry-after-anion-exchange-separation
#14
Shuhua He, Mumei Chen, Zheng Li, Haixia Cong, Lan Zhang, Qinnuan Li
For the determination of μg-mg L(-1) of FPs in 100 g L(-1) of thorium matrix with HCl medium, a method, including anion-exchange pre-separation, evaporation and inductively coupled plasma mass spectrometry (ICP-MS) measurement, was developed. The procedure parameters, such as the matrix effect of thorium, the acidity of separation, the elution curve of thorium and FPs and the temperature of evaporation were optimized by batch equilibration, column elution and evaporation experiments. It was found that the average recovery of the FPs was in the range 80 - 110%, and the RSD values were in the range 2 - 15% utilizing prior anion exchange separation of FPs from thorium samples...
2017: Analytical Sciences: the International Journal of the Japan Society for Analytical Chemistry
https://www.readbyqxmd.com/read/29116766/probing-the-influence-of-acidity-and-temperature-to-th-iv-on-hydrolysis-nucleation-and-structural-topology
#15
Jian Lin, Meiying Qie, Linjuan Zhang, Xiaomei Wang, Yuejian Lin, Wei Liu, Hongliang Bao, Jianqiang Wang
Systematic control of the molar ratio between thorium hydroxides and selenic acid and their reaction temperature under hydrothermal conditions results in four novel thorium-based selenate complexes, namely, [Th8O4(OH)8(SeO4)6(H2O)16]·(SeO4)2·13H2O (Th-1), [Th8O4(OH)8(SeO4)8(H2O)13]·7H2O (Th-2), Th(OH)2(SeO4)H2O (Th-3), and Th3(SeO4)6(H2O)6·2.5H2O (Th-4), as well as the thorium mixed selenite selenate compound Th(SeO3)(SeO4) (Th-5). Smaller [H2SeO4]/[Th(IV)] ratio or lower temperature give rise to the formation of octameric [Th8(μ3-O)4(μ2-OH)8](16+) cores in Th-1/Th-2 and infinite [Th(μ2-OH)2H2O](2+) chains in Th-3, respectively...
November 8, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/29116079/a-mesoporous-cationic-thorium-organic-framework-that-rapidly-traps-anionic-persistent-organic-pollutants
#16
Yuxiang Li, Zaixing Yang, Yanlong Wang, Zhuanling Bai, Tao Zheng, Xing Dai, Shengtang Liu, Daxiang Gui, Wei Liu, Meng Chen, Lanhua Chen, Juan Diwu, Lingyan Zhu, Ruhong Zhou, Zhifang Chai, Thomas E Albrecht-Schmitt, Shuao Wang
Many environmental pollutants inherently exist in their anionic forms and are therefore highly mobile in natural water systems. Cationic framework materials that can capture those pollutants are highly desirable but scarcely reported. Here we present a mesoporous cationic thorium-based MOF (SCU-8) containing channels with a large inner diameter of 2.2 nm and possessing a high surface area of 1360 m(2) g(-1). The anion-exchange properties of SCU-8 were explored with many anions including small oxo anions like ReO4(-) and Cr2O7(2-) as well as anionic organic dyes like methyl blue and the persistent organic pollutant, perfluorooctane sulfonate (PFOS)...
November 7, 2017: Nature Communications
https://www.readbyqxmd.com/read/29100156/samarium-doped-boron-nitride-nanotubes
#17
Wellington Marcos da Silva, Tiago Hilário Ferreira, Carlos Antônio de Morais, Alexandre Soares Leal, Edésia Martins Barros Sousa
Boron nitride nanotubes doped in situ with samarium (Sm-doped BNNTs) were synthesized at 1150°C under atmosphere of NH3/N2 gas mixture by thermal chemical vapor deposition (TCVD) using samarium oxide that is a product of the process separation of thorium and uranium tailings. The samarium in the BNNTs sample was activated by neutron capture, in a nuclear reactor, producing (152)Sm radioisotopes. The STEM-EELS spectrum and neutron activation show energies attributed to the samarium confirming the in situ doping process during BNNTs growth...
October 31, 2017: Applied Radiation and Isotopes
https://www.readbyqxmd.com/read/29098984/long-term-monitoring-of-a-water-treatment-technology-designed-for-radium-removal-removal-efficiencies-and-norm-formation
#18
Liie Lumiste Hill, Siiri Suursoo, Madis Kiisk, Alar Jantsikene, Nele Nilb, Rein Munter, Enn Realo, Rein Koch, Kaisa Putk, Maria Leier, Taavi Vaasma, Kadri Isakar
A drinking water treatment plant in Viimsi, Estonia was monitored over three years for iron, manganese, radium-226, radium-228, and their daughter nuclides in order to determine the efficiency of the treatment process, get an insight of the removal mechanisms and interactions between radium, iron, and manganese, and assess the overall longevity and performance of the technology and possible build-up of NORM from the treatment process. During the study, samples were collected from raw water, first and second stage filtrate, consumer water, backwash water, and filter materials...
November 3, 2017: Journal of Radiological Protection: Official Journal of the Society for Radiological Protection
https://www.readbyqxmd.com/read/29071001/primary-hepatic-angiosarcoma-a-case-report-with-10-year-patient-medical-data
#19
Masanori Ogawa, Ryusuke Ae, Teppei Sasahara
In the current study, we report a case of a 46-year-old man who presented with sudden abdominal pain and was diagnosed with rupture of hepatic angiosarcoma (HAS). He underwent surgery, but died 13 days after the onset of the abdominal pain. Chronic exposure to carcinogens, such as thorium dioxide, arsenic, vinyl chloride, and radium, is associated with HAS. However, our patient had not been exposed to such carcinogens. He had submitted himself for annual medical checkups since he was employed. His liver was cirrhotic, and medical history data showed that he had had fatty liver for at least 10 years before HAS onset...
September 2017: Case Reports in Oncology
https://www.readbyqxmd.com/read/29068199/understanding-the-scarcity-of-thorium-peroxide-clusters
#20
Shane S Galley, Cayla E Van Alstine, Laurent Maron, Thomas E Albrecht-Schmitt
The reaction of Th(NO3)4·5H2O with 3 equiv of 2,2',6',2″-terpyridine (terpy) in a mixture of acetonitrile and methanol results in formation of the trinuclear thorium peroxide cluster [Th(O2)(terpy)(NO3)2]3. This cluster is assembled via bridging by μ-η(2):η(2) peroxide anions between thorium centers. It decomposes upon removal from the mother liquor to yield Th(terpy)(NO3)4 and Th(terpy)(NO3)4(EtOH). The peroxide formation appears to be radiolytic in origin and is, most likely, generated from radiolysis of water by short-lived daughters generated from (232)Th decay...
November 6, 2017: Inorganic Chemistry
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