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41.
Innocent Nkurikiyimfura Yanmin Wang Bonfils Safari Emmanuel Nshingabigwi 《Particuology》2021,(1):181-200
Enhancing solar photovoltaic and thermal conversion performances may help develop more environmentally friendly hybrid photovoltaic/thermal(PV/T)systems that can be used in applications ranging from household to industrial scales.Owing to their enhanced thermal and optical properties,nanofluids have proven to be good candidates for designing PV/T systems with superior performances.As smart nanofluids,magnetic nanofluids(MNFs)can further enhance the performances of PV/T systems under external magnetic fields.This paper reviews recent developments in enhancing the electrical and thermal performances of PV/T systems using magnetic nanofluids.Various parameters affecting the performances are highlighted,and some areas for further investigations are discussed.The reviewed literature shows that PV/T systems with MNFs are promising.However,their performances need further investigation before they can be used in applications. 相似文献
42.
Tapas Kumar Mandal Nargish Parvin Sang W. Joo 《Particle & Particle Systems Characterization》2021,38(11):2100110
This study reports a fluorescence iron core-carbonized biocompatible hybrid poly(ethylene glycol) (PEG)-oriented nanogel (Fe2O3@C@PEG-COOH nanogel). The fluorescence Fe2O3@C@PEG-COOH nanogel is prepared using a facile one-pot polycondensation reaction without organic solvents or catalysts. The properties of the fluorescenceFe2O3@C@PEG-COOH nanogel are investigated by fluorescence spectroscopy, transmission electron microscopy, X-ray diffraction, and thermogravimetric analysis. A change in pH as a stimulus can trigger the release of loaded doxorubicin (DOX). Under acidic conditions, the nanogel releases the highly loaded drug slowly compared to the neutral and basic conditions, which is important for cancer treatment. The synthesized fluorescenceFe2O3@C@PEG-COOH nanogel is well dispersed in water and shows fluorescence with high photostability, good biocompatibility with a paramagnetic nature. Furthermore, the nanogel can act as a potential fluorescent probe for cell imaging. 相似文献
43.
A copper(II) ion-selective electrode based on a recently synthesized 2-quinolyl-2-phenylglyoxal-2-oxime (phenylglyoxal-alpha-monoxime) has been developed. The PVC-based membrane containing phenylglyoxal-alpha-monoxime, dibutyl phthalate as plasticizer, and sodium tetraphenylborate as anion excluder and membrane modifier, was directly coated on the surface of a platinum-wire electrode. The response of the electrode was linear with a near-Nernstian slope of 28.2 mV decade(-1) within the Cu2+ ion concentration range 1x10(-6)-1x10(-1) mol x L(-1). The response time for the proposed electrode to achieve a 95% steady potential for Cu2+ concentrations ranging from 1x10(-1) to 1x10(-6) mol x L(-1) is between 10 and 50 s, and the electrode is suitable for use within the pH range of 3 to 6.5. The electrode has a detection limit of 5x10(-7) mol x L(-1) Cu2+ and its selectivity relative to several alkali, alkaline earth, transition, and heavy metal ions was good. The coated-wire electrode could be used for at least two months without a considerable alteration of its potential. Applications of the electrode for determination of copper in milk powder samples and as an indicator electrode for potentiometric titration of Cu2+ ion using EDTA are reported. 相似文献
44.
Khorasani-Motlagh M Safari N Noroozifar M Saffari J Biabani M Rebouças JS Patrick BO 《Inorganic chemistry》2005,44(22):7762-7769
Three new verdoheme analogues with weakly coordinating anions, [OEOPFe(II)X], where OEOP is the monoanion of octaethyloxoporphyrin and X = PF(6), ClO(4), and BF(4), have been synthesized and characterized by spectroscopic methods. (1)H NMR spectroscopy reveals that the [OEOPFe(II)X] species are paramagnetic, and the iron is five-coordinate (S = 2). The oxidation of [OEOPFe(II)PF(6)] with dioxygen yields [(OEOPFe)(2)O](PF(6))(2). The structure of (mu-oxo)bis[(octaethyloxoporphinato)iron(III)] has been determined by X-ray diffraction analysis. The eight Fe-N bond distances have an average value of 2.077(3) Angstroms. The oxygen atom sits on the inversion center, and the average axial Fe-O bond length is 1.756(3) Angstroms. The average displacement of the iron(III) atom from the mean porphinato core is 0.60 Angstroms. Crystal data: crystal system, monoclinic; a = 8.7114(10) Angstroms; b = 26.102(4) Angstroms; c = 15.8323(14) Angstroms; beta = 104.134(6) degrees ; space group P2(1)/c; V = 3491.1(7) Angstroms (3); Z = 2; R1 = 0.0546, wR2 =0.1145 for data with I > 2sigma(I). 相似文献
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46.
Equilibrium and kinetic study of novel methyltrimethoxysilane magnetic titanium dioxide nanocomposite for methylene blue adsorption from aqueous media
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Parvin Alizadeh Eslami Mohammad Afzal Kamboh Hamid Rashidi Nodeh Wan Aini Wan Ibrahim 《应用有机金属化学》2018,32(6)
Novel magnetic titanium dioxide nanoparticles decorated with methyltrimethoxysilane (Fe3O4@TiO2‐MTMOS) were successfully fabricated via a sol–gel method at room temperature. The synthesized material was characterized using Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, thermogravimetric analysis and vibrating sample magnetometry. The removal efficiency of the adsorbent was evaluated through the adsorption of methylene blue (MB) dye from water samples. The adsorption isotherm and kinetics were evaluated using various models. The Langmuir model indicated a high adsorption capacity (11.5 mg g?1) of Fe3O4@TiO2‐MTMOS. The nanocomposite exhibited high removal efficiency (96%) and good regeneration (10 times) compared to Fe3O4 and Fe3O4@TiO2 at pH = 9.0. Based on the adsorption mechanism, electrostatic interaction plays a main role in adsorption since MB dye is cationic in nature at pH = 9, whereas the adsorbent acquired an anionic nature. The newly synthesized Fe3O4@TiO2‐MTMOS can be used as a promising material for efficient removal of MB dye from aqueous media. 相似文献
47.
Seyed Mohammad Seyedi Hamid Sadeghian Zohreh Safari 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):2297-2306
The synthesis of β,β′-diketodithioethers 4b–j from corresponding β,β′-dihydroxydithioethers 3b–j was carried out by a Swern oxidation using DMSO-oxalyl chloride as oxidizing agent. β,β′-Dihydroxydithioethers 3b–j were prepared by the reaction of two molar equivalents of epoxides 1b–j with dimercaptoethane 2 in the presence of a saturated aqueous solution of potassium carbonate. The reactivity behavior of imine formation of the β,β′-diketodithioethers 4b–j by 2,4-dinitrophenylhydrazine was also investigated, and a mechanism was proposed by using molecular orbital (MO) calculations. To confirm the proposed mechanism, the role of the thia function to activate hydrazone formation by measuring HOMO-LUMO energy levels was also demonstrated. 相似文献
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49.
An expeditious and effective method for synthesis of isoxazoline from aldoximes and activated alkenes using cetyltrimethylammonium cerium nitrate at room temperature is described. Reaction was completed within short time period in high yields at room temperature. 相似文献
50.
Valizadeh H Zakeri-Milani P Islambulchilar Z Tajerzadeh H 《Journal of AOAC International》2006,89(1):88-93
A simple reversed-phase high-performance liquid chromatography (HPLC) method with ultraviolet detection at 280 nm was developed for simultaneous quantitation of furosemide and hydrochlorothiazide along with phenol red as a nonabsorbable marker for in situ permeability studies in anaesthetized rats. A jejunal segment of approximately 10 cm was isolated and cannulated in both ends for inlet and outlet solution. The perfusate was collected every 10 min, and samples were analyzed using the developed method. The mobile phase was acetonitrile-water-triethylamine-glacial acetic acid (41.5 + 57.4 + 0.1 + 0.9, adjusted to pH 5.6) at a flow rate of 1 mL/min; the run time was 9 min. The calibration graphs were linear for all 3 compounds (r > 0.999) across the concentration range of 7.93-125 microg/mL for phenol red and 6.25-100 microg/mL for hydrochlorothiazide and furosemide. The limits of quantitation were 7.2, 8.9, and 6.8 microg/mL for furosemide, hydrochlorothiazide, and phenol red, respectively. The coefficients of variation for intraassay and interassay precision were less than or equal to 7.6%, and the accuracy was between 93.2-103.4%. Using the single pass intestinal perfusion technique and the suggested HPLC method for sample analysis, mean values of 0.25 x 10(-4) (+/-0.16) cm/s and 0.22 x 10(-4) (+/-0.13) cm/s were obtained for furosemide and hydrochlorothiazide, respectively. 相似文献