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41.
Hossein Abdolmohammad-Zadeh Elnaz Ebrahimzadeh 《Central European Journal of Chemistry》2010,8(3):617-625
A rapid dispersive liquid-liquid micro-extraction (DLLME) methodology based on the application of 1-hexylpyridinium hexafluorophosphate
[C6py][PF6] ionic liquid (IL) as an extractant solvent was applied for the pre-concentration of trace levels of cobalt prior to determination
by flame atomic absorption spectrometry (FAAS). 1-Phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) was employed as a chelator
forming a Co-PMBP complex to extract cobalt ions from aqueous solution into the fine droplets of [C6py][PF6]. Some effective factors that influence the micro-extraction efficiency include the pH, the PMBP concentration, the amount
of ionic liquid, the ionic strength, the temperature and the centrifugation time which were investigated and optimized. In
the optimum experimental conditions, the limit of detection (3s) and the enrichment factor were 0.70 μg L−1 and 60, respectively. The relative standard deviation (RSD) for six replicate determinations of 50 μg L−1 Co was 2.36%. The calibration graph using the pre-concentration system was linear at levels 2–166 μg L−1 with a correlation coefficient of 0.9982. The applicability of the proposed method was evaluated by the determination of
trace amounts of cobalt in several water samples.
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42.
Mohammad Yousefi Mojdeh Safari Maryam Bikhof Torbati Vahid Molla Kazemiha Hassan Sanati Amir Amanzadeh 《应用有机金属化学》2012,26(8):438-444
Since organotin complexes have been reported to show fewer side effects relative to other heavy metal anticancer compounds, in the present study we report for the first time four novel organotin(IV) derivatives with the general formula R2SnL2, where R = methyl (1), n‐butyl (2), phenyl (3), benzyl (4) and L = morpholine‐1‐carbodithioate (MCDT). The newly synthesized ligand was monodentate or bidentate, coordinating through a sulfur atom. The complexes were synthesized by directly mixing, refluxing and stirring the ligand, with diorganotin(IV) dichlorides in a suitable solvent. The complexes were found to be pure and their solid and solution phase structural configuration was investigated by FT‐IR, multinuclear NMR (1 H, 13 C, 119Sn) and mass spectrometry. Complex 2 was also studied for its thermal decomposition by thermogravimetry and differential thermal analysis. The results obtained on the basis of these techniques are in full concurrence with the proposed 1:2 (Sn:L) stoichiometry. The cytotoxic activity of the MCDT and diorganotin(IV) complexes (1–4) was tested against tumor cell lines – human cervix carcinoma HeLa and human myelogenous leukemia K562 – and normal immunocompetent cells: peripheral blood mononuclear cells PBMC. Results of bioassay demonstrated that organotin derivatives were in general more active than the anticancer drug cisplatin. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
43.
44.
Marc Escribà-Gelonch Elnaz Shahbazali Maarten Honing Volker Hessel 《Tetrahedron》2018,74(25):3143-3151
Process intensification commonly enables reaction acceleration and therefore continuous-flow/PAT is urgently needed. The low volumes typical for micro-flow pose challenges for online sampling operations in analytics. In this paper, a very fast process is combined with a modified ultra-high-performance liquid chromatography (UHPLC) system allowing for very fast sampling and analysis. Low-volume online sampling according to the needs posed by PAT for pharma quality control, is introduced here for UHPLC analysis of the photo-Claisen rearrangement in micro-flow. Chances and challenges are critically reviewed, including the reproducibility and robustness of the sampling. Furthermore, the ability and speed of the chosen set-up in order to capture process changes and adjust the process parameters properly is investigated. With the applied online sampling system, it was possible to perform, almost unattended and spending 12 times less sampling volume, a full factorial analysis of all relevant reaction conditions (243 experiments) in three days. Such quality-in-the-process-line (QuIProLi) online sampling avoided random errors due to automation. 相似文献
45.
Jouyban A Shaghaghi M Zoghi E Karami N Clark BJ Acree WE 《Journal of fluorescence》2011,21(6):2111-2116
Fluorescence intensities of propranolol and atenolol in binary solvent mixtures at various temperatures are measured and mathematical
models are proposed to represent the fluorescence intensity data. The results showed that the proposed models are able to
correlate/predict the data with reasonable error. The fluorescence intensity of pyridoxal HCl in binary solvents at 25 °C
is also determined and represented by the proposed model as an additional test probe. 相似文献
46.
Elnaz Ranjbakhsh Mohammad Izadyar Ali Nakhaeipour Aziz Habibi-Yangjeh 《International journal of quantum chemistry》2020,120(23):e26388
The photocatalytic yield of g-C3N4 for CO2 reduction was modified by phosphorus doping. Possible reaction pathways for CO2 reduction on the P-doped g-C3N4 (PCN) surface were investigated by density function theory calculations for the first time. The experimental results showed that P doping increases the carriers' lifetime, which improves the production of CH4 through the increase in the driving force of the electrons. The partial density of states of the PCN showed that the valence band maximum and conduction band minimum are composed of px, py, and, s orbitals of the N atoms and pz states of carbon, nitrogen, and phosphorus, respectively. Mechanism studies confirm that formic acid, formaldehyde, methanol, and methane are the most probable products. Methane, having positive adsorption energy, can be easily desorbed from the PCN surface, and the Gibbs activation energy of the final step is 1.98 eV. The formation of H2COOH is the rate-determining step. 相似文献
47.
Golipour-Chobar Elnaz Salimi Farshid Ebrahimzadeh Rajaei Gholamreza 《Monatshefte für Chemie / Chemical Monthly》2020,151(3):309-318
Monatshefte für Chemie - Chemical Monthly - Previous reports were shown that boron nitride nanostructures can be biocompatible and nontoxic. Therefore, interaction of lomustine as an... 相似文献
48.
Elnaz Ghasemi Ashraf S. Shahvelayati 《Phosphorus, sulfur, and silicon and the related elements》2016,191(5):746-750
Benzoylthioureidocarboxylic acids, prepared from benzoyl chlorides, potassium thiocyanate, and α-aminoacids, are used as acid components in the Ugi reaction to produce thiourea-peptoids in moderate to good yields. 相似文献
49.
Safaralizadeh Elnaz Darzi Simin Janitabar Mahjoub Ali Reza Abazari Reza 《Research on Chemical Intermediates》2017,43(2):1197-1209
Research on Chemical Intermediates - Using a simple impregnation process, the present study has introduced a novel route for the photosensitization of TiO2 nanoparticles using Sudan black B dye as... 相似文献
50.
Fragmentation reaction of highly sterically hindered TsiSiPhCl2 with some alcoholic sodium alkoxides
Kazem D. Safa Elnaz Hosseini Akbar Hassanpour Shahin Tofangdarzadeh 《Silicon Chemistry》2008,3(6):289-293
TsiSiPhCl2(1) was treated with boiling NaOEt/EtOH to give the fragmentation product of the type (Me3Si)2CHSiPh(OEt)2. Treatment of 1 with various alkoxides NaOR/ROH (R = n-Pr, n-Bu, iso-Bu, 2-Bu, amyl, iso-amyl, 2-amyl, CH2Ph) gave Me3SiCH2SiPh(OR)2 rather than the expected (Me3Si)2CHSiPh(OR)2. Study of the products showed that alkoxides as a nucleophile can not attack the silicon center bearing the (Me3Si)3C– group because of steric hindrance. It is suggested that the reaction proceeds through an elimination, analogous to E2 eliminations
of alkyl halides, involving synchronous attack of RO− at a Me3Si group, liberation of X−, and formation of (Me3Si)2C=SiPhCl. The reaction of NaOEt/EtOH with dichloride 1 takes different route from other alkoxides. 相似文献