Publications by authors named "Hamid Emadi"

5 Publications

  • Page 1 of 1

0D to 3D Pr metal-organic networks crystal engineered for optimal iodine adsorption.

Acta Crystallogr B Struct Sci Cryst Eng Mater 2020 Oct 19;76(Pt 5):779-788. Epub 2020 Aug 19.

Institute of Low Temperature and Structure Research, Polish Academy of Science, PO Box 1410, Wroclaw, 50950, Poland.

Four new praseodymium(III) metal-organic compounds varying in dimensionality from 0D to 3D have been designed and synthesized based on N-heterocyclic polycarboxylic acids, including pyridine-2,6-dicarboxylic acid (Hpydc) and pyrazine-2,3-dicarboxylic acid (Hpzdc). Altering the concentration of piperazine (pip, ancillary ligand) enables control over the dimensionality of the compound by switching between the 0D [Hpip][Hpip][Pr(pydc)]·4HO (I) and the 1D {[Pr(pydc)(Hpydc)(HO)]·4HO} (II) coordination polymer (CP). Upon replacing Hpydc with Hpzdc, CP II is converted to the 2D CP [Pr(pzdc)(Hpzdc)(HO)] (III) and using the metalloligand [Zn(Hpzdc)(HO)], the 3D heterometallic CP {[PrZn(pzdc)(HO)]·2HO} (IV) is formed. Compound IV shows high stability in the absence of uncoordinated solvent molecules and is stable up to 400°C, even in the presence of humidity. Therefore, IV was utilized for iodine adsorption in the vapour phase and in the presence of humidity. The results confirm the remarkable potential of IV for reversible adsorption of iodine vapour.
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http://dx.doi.org/10.1107/S2052520620009336DOI Listing
October 2020

Liquid Calibration Phantoms in Ultra-Low-Dose QCT for the Assessment of Bone Mineral Density.

J Clin Densitom 2020 Jan - Mar;23(1):108-116. Epub 2019 Feb 22.

Medical Physics Department, School of Medicine, Iran University of Medical Sciences, Tehran, Iran. Electronic address:

Introduction: Cortical bone is affected by metabolic diseases. Some studies have shown that lower cortical bone mineral density (BMD) is related to increases in fracture risk which could be diagnosed by quantitative computed tomography (QCT). Nowadays, hybrid iterative reconstruction-based (HIR) computed tomography (CT) could be helpful to quantify the peripheral bone tissue. A key focus of this paper is to evaluate liquid calibration phantoms for BMD quantification in the tibia and under hybrid iterative reconstruction-based-CT with the different hydrogen dipotassium phosphate (KHPO) concentrations phantoms.

Methodology: Four ranges of concentrations of KHPO were made and tested with 2 exposure settings. Accuracy of the phantoms with ash gravimetry and intermediate KHPO concentration as hypothetical patients were evaluated. The correlations and mean differences between measured equivalent QCT BMD and ash density as a gold standard were calculated. Relative percentage error (RPE) in CT numbers of each concentration over a 6-mo period was reported.

Results: The correlation values (R was close to 1.0), suggested that the precision of QCT-BMD measurements using standard and ultra-low dose settings were similar for all phantoms. The mean differences between QCT-BMD and the ash density for low concentrations (about 93 mg/cm) were lower than high concentration phantoms with 135 and 234 mg/cm biases. In regard to accuracy test for hypothetical patient, RPE was up to 16.1% for the low concentration (LC) phantom for the case of high mineral content. However, the lowest RPE (0.4 to 1.8%) was obtained for the high concentration (HC) phantom, particularly for the high mineral content case. In addition, over 6 months, the KHPO concentrations increased 25% for 50 mg/cm solution and 0.7 % for 1300 mg/cm solution in phantoms.

Conclusion: The excellent linear correlations between the QCT equivalent density and the ash density gold standard indicate that QCT can be used with submilisivert radiation dose. We conclude that using liquid calibration phantoms with a range of mineral content similar to that being measured will minimize bias. Finally, we suggest performing BMD measurements with ultra-low dose scan concurrent with iterative-based reconstruction to reduce radiation exposure.
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http://dx.doi.org/10.1016/j.jocd.2019.02.005DOI Listing
February 2019

Synthesis of some transition metal (M: Mn, Co, Ni, Cu, Zn, Ag, Cd) sulfide nanostructures by hydrothermal method.

Adv Colloid Interface Sci 2017 Aug 16;246:52-74. Epub 2017 Jun 16.

Department of Chemistry, Kosar University of Bojnord, Bojnord, Islamic Republic of Iran.

The design of nanostructures with favored shape, particle size and structure is one of the most important fields of nanoscience. To reach this target hydrothermal method is one of the most applicable methods which allow us to obtain favored structures by changing some parameters. This review focuses on synthesis of some transition metal sulfides by hydrothermal method because of technological importance of this group of material. The common sulfides of Mn, Co, Ni, Cu, Zn, Ag and Cd are introduced and a mechanism proposed for their synthesis. The effects of temperature and time reaction, surfactant, reactants concentration, metal and sulfur sources and etc. on the morphology, particle size and some properties of the products are investigated. SEM and TEM images show the morphology and size of the as-synthesized samples. Chemical composition of the samples is characterized by XRD, EDS and etc. The magnetic, optical and thermoelectric properties of the metal sulfides are investigated.
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http://dx.doi.org/10.1016/j.cis.2017.06.007DOI Listing
August 2017

Sonochemical synthesis and characterization of NiMoO4 nanorods.

Ultrason Sonochem 2013 Jan 29;20(1):418-24. Epub 2012 Aug 29.

Institute of Nano Science and Nano Technology, University of Kashan, Kashan, PO Box 87317-51167, Islamic Republic of Iran.

NiMoO(4) nanorods have been successfully synthesized by sonochemical method process by using Ni(CH(3)COO)(2) · 4H(2)O and (NH(4))(6)Mo(7)O(24) · 4H(2)O as starting materials. Some parameters including ultrasonic power, ultrasonic irradiation time, stirring effect, solvent effect, and surfactant effect were investigated to reach optimum condition. The as synthesized nanostructures were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmittance electron microscopy (TEM), photoluminescence (PL) spectroscopy, Fourier transform infrared (FT-IR) spectra and energy dispersive X-ray microanalysis (EDX). Facile preparation and separation are important features of this route. This work has provided a general, simple, and effective method to control the composition and morphology of NiMoO(4) in aqueous solution, which will be important for inorganic synthesis methodology.
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http://dx.doi.org/10.1016/j.ultsonch.2012.08.012DOI Listing
January 2013

Photoclinic. Actinomycetoma.

Arch Iran Med 2011 Jul;14(4):299-300

Department of Infectious Diseases, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran.

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http://dx.doi.org/0011144/AIM.0017DOI Listing
July 2011