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991.
Ahmadi Mostafa Rashedi Reza Ahmadjo Saeid Karimi Mahsa Zahmaty Majid Mortazavi Seyed Mohammad Mahdi 《Journal of Thermal Analysis and Calorimetry》2018,131(3):2523-2533
Journal of Thermal Analysis and Calorimetry - Development of olefin block copolymers (OBCs) based on new catalytic systems is challenging. We evaluate the performance of rac-ethylenebis(1-η... 相似文献
992.
993.
Vahid Mofid Zahra Emam-Djomeh Seyed Hadi Razavi Seyed Mohammad Taghi Gharibzahedi Farid Jahanbakhsh 《Journal of Dispersion Science and Technology》2018,39(4):469-477
Dynamic rheological measurements provide a valid determination of the ability of polymeric ingredients to compensate the reduced contribution of fat to texture and mouthfeel, as well as provide an emulsion that easily breaks down in commercial low-fat butters. In this study, the linear effects of pectin (PE, 0.5%) and xanthan gum (XG, 0.1%) and their interactions with locust bean gum (LBG, 0.2% and 0.4%), sodium-alginate (ALG, 0.2% and 0.4%), and modified starch (MS, 0.2% and 0.4%) on the flow behavior, dynamic rheological characteristics, and stability of reduced-fat butters containing 10% walnut oil (WO) were investigated. Results showed that the power law model can adequately fit the shear-rate/shear-stress data (0.888?≤?r?≤?0.992, p?0.01). Flow behavior index of all the butters was approximately in the range of 0.6–0.9, which corresponds to pseudoplastic behavior. They behaved like an elastic solid with G′?>?G″ at all frequencies. The samples prepared with PE–LBG (0.2% and 0.4%) and XG–ALG (0.4%) had the highest G′ values. The phase angle (G″/G′) decreased with increasing frequency from 0.03 to 15?Hz. The maximum apparent viscosity and stability were, respectively, found for WO butters formulated with XG–0.2% ALG and PE–0.4% LBG. 相似文献
994.
995.
Heman?Mirzapour Homayon?Ahmad?PanahiEmail authorView authors OrcID profile Elham?Moniri Alireza?Feizbakhsh 《Mikrochimica acta》2018,185(9):440
Magnetic nanoparticles (MNPs) modified with organic dendrimers are shown to be a viable sorbent of the microextraction of the drug rosuvastatin (RST; also known as Crestor). The MNPs were prepared from iron(II) chloride and iron(III) chloride and then coated with silicon dioxide. The coated MNPs produced by this method have diameters ranging from 10 to 60 nm according to scanning electron microscopy. The MNPs were further modified with organic dendrimers containing methyl methacrylate and ethylene diamine. The resulting MNPs were characterized by SEM, Fourier transform infra-red and thermal gravimetry analysis. Then, the efficacy of the modified MNPs with respect to the extraction of RST was studied. The adsorption of RST by MNPs can be best described by a Langmuir isotherm. Following elution with buffer, RST was quantified by HPLC. The method was applied to the determination of RST in (spiked) human blood plasma, urine, and in tablets. RST extraction efficiencies are 54.5% in plasma, 86.6% from the drug matrix, and 94.3% in urine. The highest adsorption capacity of the RST by the MNPs adsorbent was 61 mg?g?1. 相似文献
996.
4,13-Didecyl-1,7,10,16-tetraoxa-4,13-diazacyclooctadecane (kryptofix22DD) has been explored as a neutral ionophore for preparing polyvinyl chloride (PVC)-based membrane sensor selective to lead(II). The optimized membrane incorporating kryptofix22DD as the active material, nitrobenzene as plasticizer and sodium tetraphenylborate as an anion excluder and membrane modifier in PVC (in the weight ratio of 5.0: 63.0: 2.0: 30.0, respectively) was directly coated on the surface of graphite rod. The sensor exhibits a Nernstian slope (29.4 mV/decade) in the concentration range of 1.0 × 10–5 to 1.0 × 10–1 M Pb2+. The detection limit of the sensor is 6.5 × 10–6 M. The proposed sensor has a fast response time (~10 s), a satisfactory reproducibility and relatively long lifetime. The electrode shows high selectivity toward Pb2+ ion in comparison to other common cations. The proposed sensor is suitable for use in aqueous solutions in a wide pH range of 2.0–10.0. It was used as an indicator electrode for the end point detection in the potentiometric titration of Pb2+ ion with ethylenediaminetetraacetic acid (EDTA) and sodium iodide (NaI) solutions. The proposed sensor was successfully applied for the recovery of Pb2+ ions spiked in real water samples. 相似文献
997.
Maryam Honardoost Seyed Mohammad Ali Hosseini Rad 《Applied biochemistry and biotechnology》2018,184(2):524-537
Producing biodiesel from microalgae grown in wastewater is environment-friendly and cost-effective. The present study investigated the algae found in wastewater of a local dairy farm for their potential as biodiesel feedstocks. Thirteen native algal strains were isolated. On the basis of morphology and 16S/18S rRNA gene sequences, one strain was identified to be a member of cyanobacteria, while other 12 strains belong to green algae. After screening, two Scenedesmus strains out of the 13 microalgae isolates demonstrated superiority in growth rate, lipid productivity, and sedimentation properties, and therefore were selected for further scale-up outdoor cultivation. Both Scenedesmus strains quickly adapted to the outdoor conditions, exhibiting reasonably good growth and strong anti-contamination capabilities. In flat-plate photobioreactors (PBRs), algal cells accumulated predominantly neutral lipids that accounted for over 60% of total lipids with almost 70% being triacylglycerol. In addition, Scenedesmus obliquus had a high content of monounsaturated fatty acids, of which the amount of oleic acid (C18:1) was up to 27.11%. Based on these findings, the dairy farm wastewater-isolated Scenedesmus strains represent promising sources of low-cost, high-quality oil for biofuel production. 相似文献
998.
Alireza?KhataeeEmail author Mahsa?Haddad Irani-nezhad Javad?Hassanzadeh 《Mikrochimica acta》2018,185(3):190
It is reported that a mixture of WS2 nanosheets (WS2 NS) and silver nanoclusters (AgNCs) displays strongly enhanced peroxidase-mimicking activity. The catalytic effect of the mixture was studied by colorimetry, fluorometry, chemiluminescence (CL) and electrochemistry. The effect is interpreted in terms of a difference between the Fermi energy level of the two nanomaterials. This leads to the formation of charge separation regions which act as active sites for enzyme mimetic interaction with the substrates. The mixture of WS2 NS and AgNCs was exploited for the non-enzymatic determination of H2O2 and glucose. A stopped-flow method was applied as a sensitive CL detection system using the bicarbonate-H2O2 reaction. The mixture has a powerful peroxidase mimicking activity on the bicarbonate-H2O2 CL reaction, and this effect is much larger than that of any single constituent. In addition, the CL emission is improved several times by using the stopped-flow technique. Under optimum condition, H2O2 can be determined in the 2.5–1500 nM concentration range. Moreover, glucose levels in human serum can be quantified via glucose oxidase based oxidation which leads to the generation of H2O2. Using this CL assay, a linear relationship was obtained between the intensity of the CL emission and glucose concentration in the range of 0.03–20 μM, with a limit of detection (3S) of 13 nM. 相似文献
999.
Alireza Ranjbar-Motlagh 《Journal of Mathematical Analysis and Applications》2022,505(2):125508
The purpose of this article is to study the Besov type function spaces for maps which are defined on abstract metric-measure spaces. We extend some of the embedding theorems of the classical Besov spaces to the setting of abstract spaces. 相似文献
1000.
Shayesteh A Appadoo DR Gordon IE Bernath PF 《Journal of the American Chemical Society》2004,126(44):14356-14357
Gaseous ZnH2 and ZnD2 have been discovered in an emission source that combines an electrical discharge with a high-temperature furnace. High-resolution infrared emission spectra of ZnH2 and ZnD2 have been recorded with a Fourier transform spectrometer, and the antisymmetric stretching fundamental bands of 64ZnH2 and 64ZnD2 were detected near 1889.4 and 1371.6 cm-1, respectively. Rotational analysis of the bands yielded r0 bond distances of 1.535 271(1) and 1.531 836(9) A for linear 64ZnH2 and 64ZnD2, respectively. 相似文献