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排序方式: 共有198条查询结果,搜索用时 0 毫秒
31.
Teslime Erşan Didem Giray Dilgin Elif Kumrulu Umur Kumrulu Yusuf Dilgin 《Electroanalysis》2023,35(4):e202200295
This work describes the sensitive voltammetric determination of favipiravir (FAV) based on its reduction for the first time with a low-cost and disposable pencil graphite electrode (PGE). In addition, the determination of FAV was also performed based on its oxidation. Differential pulse (DP) voltammograms recorded in 0.5 M H2SO4 for the reduction of FAV show that peak currents increase linearly in the range of 1.0 to 600.0 μM with a limit of detection of 0.35 μM. The acceptable recovery values (98.9–106.0 %) obtained from a pharmaceutical tablet, real human urine, and artificial blood serum samples spiked with FAV confirm the high accuracy of the proposed method. 相似文献
32.
The γ-hydroxypropyl-functionalised diiron dithiolate complex [Fe2(CO)6(μ-SCH2CH2CH2OH)2] is prepared upon thermolysis of Fe3(CO)12 and HO(CH2)3SH and further reaction with dppm (dppm = Ph2PCH2PPh2) affords [Fe2(CO)4(μ-dppm)(μ-SCH2CH2CH2OH)2]. From the reaction of Fe3(CO)12 with dppm(S2) a minor product is the tetrairon cluster, [{Fe2(CO)6(μ-SCH2CH2CH2OH)}2(μ4-S)], the mode of formation of which is unclear. It has been crystallographically characterised and adopts a μ4-S bridged double butterfly structure which is compared with other crystallographically characterised complexes of this type.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
33.
Using the effective potential method, we computed one-loop corrections to the mass matrix of neutral Higgs bosons of the Non-Holomorphic Supersymmetric Standard Model (NHSSM) with explicit CP violation, where the radiative corrections due to the quarks and squarks of the third generation were taken into account. We observed that the non-holomorphic trilinear couplings can compete with the holomorphic ones in CP violating issues for the mass and mixing of the neutral Higgs bosons. 相似文献
34.
Ertekin E Winkler MT Recht D Said AJ Aziz MJ Buonassisi T Grossman JC 《Physical review letters》2012,108(2):026401
Hyperdoping has emerged as a promising method for designing semiconductors with unique optical and electronic properties, although such properties currently lack a clear microscopic explanation. Combining computational and experimental evidence, we probe the origin of sub-band-gap optical absorption and metallicity in Se-hyperdoped Si. We show that sub-band-gap absorption arises from direct defect-to-conduction-band transitions rather than free carrier absorption. Density functional theory predicts the Se-induced insulator-to-metal transition arises from merging of defect and conduction bands, at a concentration in excellent agreement with experiment. Quantum Monte Carlo calculations confirm the critical concentration, demonstrate that correlation is important to describing the transition accurately, and suggest that it is a classic impurity-driven Mott transition. 相似文献
35.
Elif Parlak 《Journal of Dispersion Science and Technology》2018,39(10):1403-1408
Water insoluble sulfonated cellulose was prepared and applied for Cu2+ removal from water. The effects of sorbent dose, initial solution pH, temperature and initial Cu2+ concentration on the removal performance of sulfonated cellulose were investigated. Isothermal data were modeled with the Langmuir and Freundlich isotherm models. The Cu2+ sorption onto sulfonated cellulose followed the Langmuir isotherm model with the maximum sorption capacity of 8.2?mg-Cu2+/g. Removal of Cu2+ showed rapid initial kinetics; in 3?min removal of Cu2+ reached equilibrium status. Thermodynamic study revealed an exothermic sorption process. In addition, sulfonated cellulose is a kind of green and renewable sorbent because it can be easily regenerated by 0.1?M HCl. 相似文献
36.
Elif Gungor Mustafa Burak Coban Hulya Kara Yasemin Acar 《Journal of Cluster Science》2018,29(3):533-540
A new open-cubane MnIII, [{(H2O)MnIIIL}{MnIIIL}]2·2(CH3OH).2(CH3CH2OH)·2Cl, 1 where H 2 L=[N-(2-hydroxyethyl)-3-methoxysalicylaldimine] has been synthesized and characterized by element analysis, FT-IR, solid UV–Vis spectroscopy and single crystal X-ray diffraction. The crystal structure determination shows an open-cubane tetranuclear complex. The Mn1 (Mn1i) ions is hexacoordinate by NO5 donor sets while the Mn2 (Mn2i) is pentacoordinate by NO4 donor sets. The solid state photoluminescence properties of complex 1 and its ligand H 2 L have been investigated under UV light at 349 nm in the visible region. H 2 L exhibits blue emission while complex 1 shows orange-red emission at room temperature. Variable-temperature magnetic susceptibility measurements on the complex 1 in the range 2–300 K indicate an antiferromagnetic interaction. 相似文献
37.
Anthony Birri Graeme Hogarth Elif Subasi 《Journal of organometallic chemistry》2007,692(12):2448-2455
Allyl-palladium dithiocarbamate complexes, [Pd(allyl)(S2CNR2)], have been prepared from the addition of dithiocarbamate salts to [Pd(allyl)(μ-Cl)]2 and TGA and DSC studies have been carried out in order to assess their potential as MOCVD precursors to palladium sulfides. For comparison [(η3-C4H7)Pd(S2PPh2)] and [Pd(S2CNMeR)2] (R = Bu, Hex) have also been prepared and tested as precursors. The unsymmetrical dithiocarbamate complex, [(η3-C3H5)Pd(S2CNMeHex)], which has a melting point of 65 °C was selected as the best single source precursor and thin films of predominantly Pd2.8S were deposited on glass slides. The crystal structures of [(η3-C4H7)Pd(S2CNMe2)], [(η3-C4H7)Pd(S2CNPr2)], [(η3-C4H7)Pd(S2PPh2)] and [Pd(S2CNMeBu)2] are reported. All except [(η3-C4H7)Pd(S2CNPr2)] show weak intermolecular S?H or Pd?H interactions. 相似文献
38.
Elif Varhan Oral Özge Tokul-Ölmez İsmail Yener Mehmet Firat Zeki Tunay Pınar Terzioğlu 《Analytical letters》2019,52(2):320-336
Aerial parts and roots of the 12 Allium species collected from five localities of Turkey were studied for trace elements (Ag, As, Cd, Co, Cr, Cu, Ni, Pb, Se, Tl, V, and Zn) using inductively coupled plasma mass spectrometry (ICP-MS). A tomato leaves certified reference material was used to characterize the accuracy and precision of the analysis. Each Allium species contained Se (315–2740?µg/kg), Tl (2.75–71?µg/kg), V (77–6790?µg/kg), and Zn (3.73–26.6?mg/kg) which can meet the necessary daily intake of these minerals. In addition, chemometric analyses were performed using correlation analysis, principal component analysis, and hierarchical cluster analysis to determine the association of 12 trace elements in the Allium species. Using chemometrics, the distribution of elements between aerial parts and roots, and geographic collection localities of Allium species were also examined. This study is important the consumers because of the wide consumption of Allium species. This report is the first detailed characterization of the metal content of Allium species. 相似文献
39.
As communication systems evolve to better cater to the needs of machine-type applications such as remote monitoring and networked control, advanced perspectives are required for the design of link layer protocols. The age of information (AoI) metric has firmly taken its place in the literature as a metric and tool to measure and control the data freshness demands of various applications. AoI measures the timeliness of transferred information from the point of view of the destination. In this study, we experimentally investigate AoI of multiple packet flows on a wireless multi-user link consisting of a transmitter (base station) and several receivers, implemented using software-defined radios (SDRs). We examine the performance of various scheduling policies under push-based and pull-based communication scenarios. For the push-based communication scenario, we implement age-aware scheduling policies from the literature and compare their performance with those of conventional scheduling methods. Then, we investigate the query age of information (QAoI) metric, an adaptation of the AoI concept for pull-based scenarios. We modify the former age-aware policies to propose variants that have a QAoI minimization objective. We share experimental results obtained in a simulation environment as well as on the SDR testbed. 相似文献
40.