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21.
Hasanabadi Salman Sadrameli Seyed Mojtaba Soheili Hassan Moharrami Hamid Heyhat Mohammad Mahdi 《Journal of Thermal Analysis and Calorimetry》2019,136(3):1201-1216
Journal of Thermal Analysis and Calorimetry - High thermal conductivity in phase change materials (PCM) is preferred in thermal energy storage (TES) systems. Carbon additives are considered as... 相似文献
22.
Two modifications of the oxotellurate(VI) PbCuTeO5 were isolated as single crystals from product mixtures obtained from solid state reactions, whereas single crystals of the oxotellurates(IV) PbCuTe2O6 and [Pb2Cu2(Te4O11)](NO3)2 were grown under hydrothermal conditions. The crystal structures of all compounds comprise of characteristic coordination polyhedra, viz. nearly square [CuO4] plaquettes for divalent copper, octahedral [TeO6] units for hexavalent tellurium, trigonal‐pyramidal [TeO3] and bisphenoidal [TeO4] groups for tetravalent tellurium, and distorted [PbOx] polyhedra for divalent lead. PbCuTeO5 is dimorphic and crystallizes in a monoclinic and a triclinic modification, related by a translationengleiche group‐subgroup relation of index 2. PbCuTe2O6 represents the ideal composition of the rare mineral choloalite. The characteristic feature of the crystal structure of [Pb2Cu2(Te4O11)](NO3)2 is its layered set‐up, comprised of cationic [Pb2Cu2(Te4O11)]2+ ribbons (width approximately 6.7 Å) sandwiched between nitrate anions that are only weakly bound to the cationic layers. 相似文献
23.
Feng Li Melisa Rodas Ceballos Sepideh Keshan Balavandy Jingxi Fan Mohammad Mahdi Khataei Yadollah Yamini Fernando Maya 《Journal of separation science》2020,43(9-10):1854-1866
In the last 5 years, additive manufacturing (three‐dimensional printing) has emerged as a highly valuable technology to advance the field of analytical sample preparation. Three‐dimensional printing enabled the cost‐effective and rapid fabrication of devices for sample preparation, especially in flow‐based mode, opening new possibilities for the development of automated analytical methods. Recent advances involve membrane‐based three‐dimensional printed separation devices fabricated by print‐pause‐print and multi‐material three‐dimensional printing, or improved three‐dimensional printed holders for solid‐phase extraction containing sorbent bead packings, extraction disks, fibers, and magnetic particles. Other recent developments rely on the direct three‐dimensional printing of extraction sorbents, the functionalization of commercial three‐dimensional printable resins, or the coating of three‐dimensional printed devices with functional micro/nanomaterials. In addition, improved devices for liquid–liquid extraction such as extraction chambers, or phase separators are opening new possibilities for analytical method development combined with high‐performance liquid chromatography. The present review outlines the current state‐of‐the‐art of three‐dimensional printing in analytical sample preparation. 相似文献
24.
Mahdi Sadeghi Nadia Zandi Mahdi Bakhtiari 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(2):777-783
61Cu is positron emitter and can be used as the PET and molecular imaging. In this study cyclotron production of 61Cu via 61Ni(p,n)61Cu, natNi(p,x)61Cu, natNi(d,x)61Cu, natNi(α,x)61Cu, natZn(p,x)61Cu and 59Co(α,2n)61Cu reactions was investigated. The ALICE/ASH (hybrid and GDH models) and TALYS-1.2 codes were used to calculate excitation
functions for proton, alpha and deuteron induced on natNi, proton on 61Ni and natZn and also alpha-particle on 59Co targets that lead to the production of 61Cu radioisotopes using intermediate energy accelerators. In addition, we compared the data obtained from in this study with
the reported measurement by experimental data. Moreover, optimal thickness of the targets and physical yield were obtained
by stopping and range of ions in matter code for each reaction. Eventually 61Ni(p,n)61Cu and 59Co(α,2n)61Cu reaction to produce 61Cu in no-carrier added state with high production yield was suggested. Finally the natNi(p,x)61Cu reaction was employed to test the target preparation using electroplating technique. 相似文献
25.
Samadi N Manayi A Vazirian M Samadi M Zeinalzadeh Z Saghari Z Abadian N Mozaffarian VO Khanavi M 《Natural product research》2012,26(20):1931-1934
The essential oil obtained from the flowering parts of Anthemis altissima L. var. altissima was analysed by gas chromatography and gas chromatography mass spectroscopy. In this study, 34 compounds representing 98.76% of the essential oil were identified. The main components were α-terpineol (26.42%), β-pinene (9.23%), cis-chrysanthenyl acetate (6.30%), globulol (5.36%), n-tricosane (4.41%), terpinen-4-ol (4.08%) and 1,8 cineole (3.84%). Antibacterial activities of the essential oil and its two major components (α-terpineol and β-pinene) were determined using microdilution method against both Gram-positive (Staphylococcus aureus, Bacillus subtilis, Staphylococcus epidermidis) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae) bacteria. The essential oil showed a broad-spectrum antibacterial activity (MICs ranged from 3.13 to 6.25?μL?mL(-1)). It was found that α-terpineol with minimum inhibitory concentration (MIC) values of the range 0.87-1.56?μL?mL(-1) was a more potent antibacterial agent than β-pinene with MIC values of the range 1.56-6.25?μL?mL(-1). All of them, the essential oil, β-pinene and α-terpineol, were more effective against Gram-positive bacteria than Gram-negative ones. 相似文献
26.
New Polydentate Trimethylsilyl Chalcogenide Reagents for the Assembly of Polyferrocenyl Architectures 下载免费PDF全文
Mahmood Azizpoor Fard Bahareh Khalili Najafabadi Mahdi Hesari Prof. Dr. Mark S. Workentin Prof. Dr. John F. Corrigan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(23):7037-7047
A series of polychalcogenotrimethylsilane complexes Ar(CH2ESiMe3)n, (Ar=aryl; E=S, Se; n=2, 3, and 4) can be prepared from the corresponding polyorganobromide and M[ESiMe3] (M=Na, Li). These represent the first examples of the incorporation of such a large number of reactive ?ESiMe3 moieties onto an organic molecular framework. They are shown to be convenient reagents for the preparation of the polyferrocenylseleno‐ and thioesters from ferrocenoyl chloride. The synthesis, structures, and spectroscopic properties of the new silyl chalcogen complexes 1,4‐(Me3SiECH2)2(C6Me4) (E=S, 1 ; E=Se, 2 ), 1,3,5‐(Me3SiECH2)3(C6Me3) (E=S, 3 ; E=Se, 4 ) and 1,2,4,5‐(Me3SiECH2)4(C6H2) (E=S, 5 ; E=Se, 6 ) and the polyferrocenyl chalcogenoesters [1,4‐{FcC(O)ECH2}2(C6Me4)] (E=S, 7 ; E=Se, 8 ), [1,3,5‐{FcC(O)ECH2}3(C6Me3)] (E=S, 9 ; E=Se, 10 ) and [1,2,4,5‐{FcC(O)ECH2}4(C6H2)] (E=S, 11 illustrated; E=Se, 12 ) are reported. The new polysilylated reagents and polyferrocenyl chalcogenoesters have been characterized by multinuclear NMR spectroscopy (1H, 13C, 77Se), electrospray ionization mass spectrometry and, for complexes 1 , 2 , 3 , 4 , 7 , 8 , and 11 , single‐crystal X‐ray diffraction. The cyclic voltammograms of complexes 7 – 11 are presented. 相似文献
27.
A facile, one-pot synthesis of new phenanthridine derivatives by a three-component reaction between phenantridine, dialkyl acetylenedicarboxylates(DAADs), and aromatic aldehydes is described. The reaction is characterized by mild conditions, high selectivity, and tolerance to various functional groups. 相似文献
28.
Karim Akbari Dilmaghani Behzad Zeynizadeh Mahdi Yari 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1722-1728
The one-pot condensation of aromatic aldehydes, β-dicarbonyl compounds, and urea or thiourea in the presence of H2SO4 supported on silica gel or alumina (80% m/m) in refluxing n-hexane produces 3,4-dihydropyrimidin-2(1H)-ones and their sulfur derivatives in high to excellent yields. 相似文献
29.
The efficient market hypothesis (EMH) states that asset prices fully reflect all available information. As a result, speculators cannot predict the future behavior of asset prices and earn excess profits at least after adjusting for risk. Although initial tests of the EMH were performed on stock market data, the EMH was soon applied to other markets including foreign exchange (FX). This study uses the detrended fluctuation analysis (DFA) technique to test 01:12:2005–18:04:2010 Iranian Rial/US Dollar exchange rate time series data to see if it can be explained by the weak form of the EMH. Moreover, to determine changes in the degree of inefficiency over time, the whole period has been divided into four subperiods. The study shows that the Iranian Forex market (the Rial/Dollar case) is weak-form inefficient over the whole period and in each of the subperiods. However, the degree of inefficiency is not constant over time. The findings suggest that profitable risk-adjusted trades could be made using past data. 相似文献
30.
Mahdi Tohidian Mohadeseh Nouri Elham Jaafarnia Amir Hossein Haghighi 《Journal of Macromolecular Science: Physics》2015,54(1):17-31
The preparation and characterization of a new type of nanocomposite polyelectrolyte membrane, based on DuPont Nafion/imidazole-modified nanosilica (Im-Si), for direct methanol fuel cell applications is described. Related to the interactions between the protonated imidazole groups, grafted on the surface of nanosilica, and negatively charged sulfonic acid groups of Nafion, new electrostatic interactions can be formed in the interface of Nafion and Im-Si which result in both lower methanol permeability and also higher proton conductivity. Physical characteristics of these manufactured nanocomposite membranes were investigated by scanning electron microscopy, thermogravimetry analysis, differential scanning calorimetry, Fourier transform infrared spectroscopy, water uptake, methanol permeability, and ion-exchange capacity, as well as proton conductivity. The Nafion/Im-Si membranes showed higher proton conductivity, lower methanol permeability and, as a consequence, higher selectivity parameter in comparison to the neat Nafion or Nafion/silica membranes. The obtained results indicated that the Nafion/Im-Si membranes could be utilized as promising polyelectrolyte membranes for direct methanol fuel cell applications. 相似文献