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This paper presents the oil uptake of porous sorbent polymer sheets consisting of ultra‐high molecular weight polyethylene. A comprehensive set of experiments are performed showing the saturation contact time, retention value, mechanical properties, oil pick‐up ratio, pick‐up density, and dynamic dripping profile. Kinetic modeling of the oil sorption is also provided. The experimental results show a good correlation with the pseudo‐second order model. The sheets exhibit high oil uptake speeds, requiring less than 2 min in contact with the oil to reach saturation. The sheets fulfill the criteria of high uptake kinetics, high sorption capacity, and high mechanical strength simultaneously. Those characteristics enable their use in practical spill response. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
23.
Mandana Amiri Elham Ghasempour Abolfazl Bezaatpour 《Journal of Solid State Electrochemistry》2014,18(4):1005-1013
The adsorption processes of alizarin onto hydrophilic carbon nanoparticles (Emperor 2000?) are investigated. The significant increase in voltammetric responses for pre-adsorbed alizarin compared with those for solution confirms high affinity of alizarin to carbon nanoparticles (possibly due to π–π stacking interaction between aromatic rings of alizarin and surface-sulfonated carbon nanoparticles). To obtain the optimum of adsorption conditions, the effects of pH, agitation rate, and adsorption time are investigated. Under square wave voltammetry conditions, the peak current for the reduction of alizarin shows a linear relationship with concentration in the range from 2.0 to 10.0 nM. The limit of detection is estimated 5.8?×?10?9 mol L?1. Next, alizarin is applied as a receptor for sensing of trace vanadium in acetate buffer pH 5. Linear calibration curves are obtained for vanadium in the range of 1.0?×?10?6 to 1.0?×?10?4 mol L?1 and the limit of detection is estimated 9.6?×?10?8 mol L?1. Determination of vanadium in real samples such as sea and tap water is demonstrated. 相似文献
24.
Alireza Najafi Chermahini Mehdi Rezapour Abbas Teimouri 《Journal of inclusion phenomena and macrocyclic chemistry》2014,79(1-2):205-214
A density functional theory based on interaction of alkali metal cations (Li+, Na+, K+, Rb+ and Cs+) with cyclic peptides constructed from 3 or 4 alanine molecule (CyAla3 and CyAla4), has been investigated using mixed basis set (C, H, O, Li+, Na+ and K+ using 6-31+G(d), and the heavier cations: Rb+ and Cs+ using LANL2DZ). The minimum energy structures, binding energies, and various thermodynamic parameters of free ligands and their metal cations complexes have been determined with B3LYP and CAM-B3LYP functionals. The order of interaction energies were found to be Li+ > K+ > Na+ > Rb+ > Cs+ and Li+ > Na+ > K+ ? Rb+ > Cs+, calculated at CAM-B3LYP level for the M/CyAla3 and M/CyAla4 complexes, respectively. Their selectivity trend shows that the highest cation selectivity for Li+ over other alkali metal ions has been achieved on the basis of thermodynamic analysis. The main types of driving force host–guest interactions are investigated, the electron-donating O offers lone pair electrons to the contacting LP* of alkali metal cations. 相似文献
25.
Jens Moons Dr. Francisco de Azambuja Jelena Mihailovic Karoly Kozma Dr. Katarina Smiljanic Mehran Amiri Prof. Tanja Cirkovic Velickovic Prof. May Nyman Prof. Tatjana N. Parac-Vogt 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(23):9179-9186
The selective hydrolysis of proteins by non-enzymatic catalysis is difficult to achieve, yet it is crucial for applications in biotechnology and proteomics. Herein, we report that discrete hafnium metal-oxo cluster [Hf18O10(OH)26(SO4)13⋅(H2O)33] ( Hf18 ), which is centred by the same hexamer motif found in many MOFs, acts as a heterogeneous catalyst for the efficient hydrolysis of horse heart myoglobin (HHM) in low buffer concentrations. Among 154 amino acids present in the sequence of HHM, strictly selective cleavage at only 6 solvent accessible aspartate residues was observed. Mechanistic experiments suggest that the hydrolytic activity is likely derived from the actuation of HfIV Lewis acidic sites and the Brønsted acidic surface of Hf18 . X-ray scattering and ESI-MS revealed that Hf18 is completely insoluble in these conditions, confirming the HHM hydrolysis is caused by a heterogeneous reaction of the solid Hf18 cluster, and not from smaller, soluble Hf species that could leach into solution. 相似文献
26.
Nosrati Sahar Molavipordanjani Sajjad Emami Saeed Abedi Seyed Mohammad Talebpour Amiri Fereshteh Hosseinimehr Seyed Jalal 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(1):205-211
This study presents [99mTc]BPTG-1 and [99mTc]BPTG-2 for glioblastoma imaging. In vitro cellular uptakes of these radiotracers were examined in SKOV-3, MCF-7, U87-MG, HT-29, and A549 cell lines. U87-MG cell line displayed the highest radiotracers uptakes. Biodistribution study in U87-MG tumor bearing mice revealed higher uptake of radiotracers in tumor than muscle and brain. Liver, intestine, and kidneys displayed the highest radioactivity uptakes. The main route of radiotracers elimination was hepatobiliary. Due to the brain uptake of these radiotracers, they are promising radiotracers for future studies in the diagnosis of glioblastoma.
相似文献27.
Kohzadian Alireza Filian Hossein Kordrostami Zahra Zare Abdolkarim Ghorbani-Choghamarani Arash 《Research on Chemical Intermediates》2020,46(3):1941-1953
Research on Chemical Intermediates - In this paper, a rapid, easy and very efficient method for the synthesis of bis(pyrazolyl)methanes has been reported in the presence of nickel–guanidine... 相似文献
28.
Aziz Ahmadi-khaneghah Alireza Pourali 《International Journal of Polymer Analysis and Characterization》2020,25(6):444-456
Abstract In this work, three epoxy resins including diglycidyl ethers of N,N′-bis(2-hydroxyethyl)pyromellitimide (DIDGE), bisphenol-A (BADGE), and polyethylene glycol (PEDGE) were isothermally cured by an amine curing agent possessing N,N′-disubstituted pyromellitimide units (denoted by DIDAM). DIDGE resin was synthesized from the reaction of N,N′-bis(2-hydroxyethyl)pyromellitimide with an excess of epichlorohydrin. Also, DIDAM curing agent was prepared from the reaction of pyromellitic dianhydride with an excess of ethylene diamine. Completion of the isothermal curing processes was approved by both Fourier transform-infrared spectroscopy and non-isothermal differential scanning calorimetry (DSC). The DSC traces showed only the phase transitions related to the thermal degradation of the resulting thermosets. According to the thermogravimetric analyses, the DIDGE/DIDAM thermoset showed higher thermal stability at temperatures above 425?°C than the other two thermosets. While BADGE/DIDAM and PEDGE/DIDAM thermosets showed about 70% weight loss in the thermal range of 400–850?°C, DIDGE/DIDAM thermoset was encountered with only about 40% weight loss. The glass transition temperatures (Tg ) of the resulting thermosets were determined using tan δ vs temperature plots obtained from dynamic mechanical thermal analysis. The Tg values of BADGE/DIDAM, DIDGE/DIDAM, and PEDGE/DIDAM thermosets were found to be 211?°C, 189?°C, and 81?°C, respectively. 相似文献
29.
Masoumeh Ghasempour Alireza Iranbakhsh Mostafa Ebadi Zahra Oraghi Ardebili 《等离子体物理论文集》2020,60(4):e201900159
The plasma-primed seeds of Catharanthus roseus were cultured in a hormone-free culture medium under sterile conditions. Plasma of 30 or 60 s improved root length (mean = 41.4%) and biomass (mean = 47%), whereas plasma of 90 s delayed plant growth. The plasma treatments enhanced concentrations of photosynthetic pigments and soluble phenols. Plasma of 90 s increased the proline level. With a similar trend, plasma priming induced activities of phenylalanine ammonia-lyase, catalase (about twofold) and peroxidase (31%) enzymes. Plasma also upregulated the expressions of deacetylvindoline O-acetyltransferase gene by an average of 7.8 times. Similarly, the plasma-treated seedlings contained higher concentrations of alkaloids (mean = 72%). Here, molecular evidence is provided on the plasma-associated modifications in secondary metabolism. 相似文献
30.
Amirhassan Amiri Hamid Reza Saadati-Moshtaghin Abbas Abdar Farokhzad Mohammadi Zonoz 《International journal of environmental analytical chemistry》2013,93(11):1017-1029
ABSTRACTIn this work, the magnetic sorbent was developed by covalent binding of a Schiff base ligand, N,N’-bis(3-salicyliden aminopropyl)amine (salpr), on the surface of silica coated magnetic nanoparticles (Salpr@SCMNPs). The core-shell nanoparticle was applied for the magnetic solid-phase extraction (MSPE) combined with dispersive liquid-liquid microextraction (DLLME) of phenolic compounds from water samples prior to gas chromatography-flame ionisation detector (GC?FID). Characterisation of the Salpr@SCMNPs was performed with different physicochemical methods such as Fourier transform infrared (FT-IR), scanning electron microscopy (SEM) and vibrating sample magnetometer (VSM). Variables affecting the performance of both extraction steps such as pH of the water sample, the sorbent amount, the desorption conditions, the extraction time; and extraction solvent were studied. Under the optimised conditions, the analytical performances were determined with a linear range of 0.01–100 ng mL?1 and a limit of detection at 0.003–0.02 ng mL?1 for all of the analytes studied. The intra-day (n = 5) and inter-day (n = 3) relative standard deviations (RSD%) of three replicates were each demonstrated in the range of 6.9–8.9% and 7.3–10.1%, respectively. The proposed method was executed for the analysis of real water samples, whereby recoveries in the range of 92.9–99.0% and RSD% lower than 6.1% were attained. 相似文献