Dae-Won Park

Korea Maritime and Ocean University · Division of Electronics and Electrical Engineering

Heterogeneous catalysts based on defective metal-organic frameworks (MOFs) have attracted wide attention due to their facile formation of defects during synthesis. Herein, two MOFs, MOF-801(D) and MOF-801(P), were synthesized by a solvothermal method using a modulation approach. The synthesized MOFs were characterized by using PXRD, N2 BET, TGA, NH...

In CO2 transformation catalysis, the synthesis of cyclic carbonates using two classes of MOF catalysts viz., zeolitic imidazolate frameworks (ZIF) and MOFs with carboxylate-capped SBUs have gained large attention. Herein we propose the strategy of employing a unified multifunctional framework formed in the metal-centered assembly of imidazole and a...

Three-dimensional amino acid backbone Cu-aspartate metal organic frameworks {[Cu(l-asp)(1,4-bpy)0.5].H2O}n (CuAspBpy) were prepared from copper salt, l-aspartic acid linker, and 4,4′-bipyridyl cross-linker by solvothermal and microwave methods. The synthesized CuAspBpy was characterized and used as a catalyst for the synthesis of propylene carbonat...

Crystalline porous materials (CPM)-200-In and CPM-200-In/Mg metal-organic frameworks (MOFs) were synthesized by a solvothermal method and were characterized by using powder X-ray diffraction (PXRD), FT-IR, Brunauer–Emmett–Teller (BET), temperature programmed desorption (TPD), TGA, XPS, and SEM-EDS. They were used as heterogeneous catalysts for the...

Two new entangled Cu(II)-based metal–organic frameworks (MOFs) have been synthesized, namely [Cu(BDC)(BPDB)0.5]n (PNU-25) and [Cu(NH2-BDC)(BPDB)0.5]n (PNU-25-NH2), using a H2O-MeOH solvent mixture. Both the PNU-25 and PNU-25-NH2 MOF materials were characterized by various analytical techniques and their catalytic potential of CO2 fixation into cycl...

An Al3+-based metal-organic framework (MOF), CAU-11-COOH, with a V-shaped ligand, DPSDA (3,3'-4,4'-diphenylsulfonetetracarboxylic dianhydride), was prepared using the solvothermal method, and was characterized using powder X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, ele...

Two aluminum-based DUT (Dresden University of Technology) metal organic frameworks were synthesized, and their structural and chemical properties were exploited for the cycloaddition reaction of CO2 and epoxide under solvent-free condition. Both the catalysts have the same supramolecular architecture but different ligands. DUT-5 (Al(OH)(bpdc), bpdc...

A series of highly thermally and hydrolytically stable porous solid with intriguing properties of zirconium- and hafnium-based metal-organic frameworks (Dresden University of Technology (DUT) series) was synthesized. The DUT metal-organic frameworks were found to be effective catalysts for both epoxide-CO2 cycloaddition reactions and the catalytic...

A hierarchically micro- and mesoporous MIL-88-NH2 metal organic framework was prepared through an easy template directed methodology. Hierarchically porous MIL-88-NH2 promoted the CO2 fixation reactions with epoxide to yield cyclic carbonates at atmospheric pressure, low reaction temperature and solventless condition. Significant conversion of epox...

We synthesized two new adenine-based Zn(II)/Cd(II) metal-organic frameworks (MOFs), namely, [Zn2(H2O)(stdb)2(5H-Ade)(9H-Ade)2] n (PNU-21) and [Cd2(Hstdb)(stdb)(8H-Ade)(Ade)] n (PNU-22), containing auxiliary dicarboxylate ligand (stdb = 4,4'-stilbenedicarboxylate). Both MOFs were characterized by multiple analytical techniques such as single-crystal...

Vanadium containing 3D MOF, MIL-47 displayed excellent synergistic catalysis with alkyl ammonium halides (TBAX) in the room temperature fixation of CO2. Theoretical intrinsic-reaction-coordinate calculations were performed at the level of M06/LACVP**++ implemented in Jaguar v8.5 software to ascertain the mechanistic pathways of catalysis. A homogen...

The synthesis of heterogeneous catalysts with multiple active sites for the synthesis of cyclic carbonate from epoxide and CO 2 has long been of great interest. Herein, we synthesized zinc metal-based multi-variate metal organic frameworks (MOFs) by incorporating different functionalized ligands into a single framework. Chemically functionalized 1,...

This study demonstrates a facile approach for modifying the UiO‐66‐NH2 metal‐organic framework by incorporating imidazolium‐based ionic liquids to form bifunctional heterogeneous catalysts for the cycloaddition of epoxides to CO2. Methylimidazolium (ILA) and methylbenzimidazolium (ILB)‐based IL units were introduced into the pore walls of UiO‐66‐NH...

A zinc-based zeolitic imidazolium framework ZIF-71 was synthesized at room temperature and its structural and physical properties were exploited for the CO2-epoxide cycloaddition reactions. ZIF-71 is found to catalyze the synthesis of cyclic carbonates under both high (120 °C, co-catalyst free) and low temperature (room temperature, with co-catalys...

A two-dimensional Zn-based metal-organic framework has been synthesized by using Zn(II) ions and H2SDC (4,4′-stilbenedicarboxylic acid) under solvothermal conditions. The framework having a trinuclear Zn3-(RCO2)6 SBUs connected by the 4,4′-stilbenedicarboxylic acid to form a hexagonal network, shows a two-dimensional structure and displays high the...

A Ni based metal organic framework Ni2(BDC)2(DABCO) has been synthesized by using Ni(II) ions and BDC (1,4-benzendicarboxylic acid) and DABCO (1,4-diazabicyclo[2.2.2]octane) ligands under solvothermal conditions. The prepared catalyst has been analyzed using various physicochemical techniques such as PXRD, FT-IR, ICP-OES, XPS, NH3-TPD, CO2-TPD, and...

A pyridinium-based ionic liquid-decorated 1D MOF (IL-[In2(dpa)3(1,10-phen)2]) was developed as a bifunctional heterogeneous catalyst system for CO2-oxirane coupling reactions. An aqueous-microwave route was employed as competent with the hydrothermal pathway for the synthesis of [In2(dpa)3(1,10-phen)2] MOF, and the IL-[In2(dpa)3(1,10-phen)2] cataly...

Two highly stable isoreticular metal-organic frameworks comprising chains of zirconium coordinated with linkers of 1,4-H2BDC (1,4-benzenedicarboxylic acid) and 4,4′-H2BPDC (4,4′-biphenyldicarboxylic acid), denoted as MIL-140A and MIL-140C, were synthesized. The catalytic activity of these frameworks was studied for the coupling reaction of CO2 and...

The aqueous synthesis of a bimetallic metal organic framework (MOF) with Ni and Co as the active metal centers and benzene-1,4-dicarboxylic acid as a linker has been achieved rapidly in high yield using microwave irradiation. The synthesized MOF is investigated for its catalytic efficacy in the synthesis of cyclic carbonates from epoxides and CO2....

The correlation between dimensionality and active sites on deciding the catalytic performance of an MOF catalyst in CO2-epoxide cycloaddition reactions has been studied. Seven In(III) based MOFs built from carboxylic and N-donor ligands, possessing different dimensionalities and distinct coordination environments were chosen as solid acid catalysts...

A multilinker non-interpenetrated metal-organic framework, UMCM-15, was synthesized by using microwave power as an alternative energy-efficient tool for the first time. The synergistic catalytic activity, when combined with a co-catalyst containing a strongly nucleophilic anion, was studied in the solventless room temperature cycloaddition between...

Zeolitic imidazolate framework ZIF-23 was prepared and used as catalyst for the solventless synthesis of cyclic carbonate from CO2 and propylene oxide with or without TBAB co-catalyst. ZIF-23 catalysts were prepared by a solvothermal or microwave method and they were characterized by various physicochemical techniques such as XRD, FT-IR, BET, TGA,...

The catalytic potential of a chloro-functionalized zeolitic imidazolate framework ZIF-95 was investigated for the solventless cycloaddition of carbon dioxide with epoxides. The reaction parameters were optimized and moderate set of reaction conditions (80 °C and 1.2 MPa CO2 pressure) were chosen for the detailed catalytic study. Eventhough ZIF-95 a...

An energy efficient and economically viable bimetallic heterogeneous catalyst system composed of Co and Zn as active centers and 2-methylimidazole as a linker has been synthesized in water at room temperature. The synthesized material (CZ-ZIF) possesses a sodalite topology, similar to the parent materials, ZIF-8 and ZIF-67, with a high surface area...

A dual-porous three-dimensional (3D) metal-organic framework [Zn4O(2,6-NDC)(BTB)4/3] (MOF-205, BET = 4200 m2/g) has been synthesized using microwave power as an alternative energy source for the first time, and its catalytic activity has been exploited for the CO2-epoxide coupling reactions to produce five membered cyclic carbonates under solvent-f...

The standalone catalytic potential of common organic bases such as imidazole, pyridine and dimethylaminopyridine (DMAP) for the solvent-free cycloaddition of CO2 with epoxides yielding five-membered cyclic carbonates is reported here. Appreciable conversion of various epoxides with excellent selectivity towards the desired products was materialized...

The efficacy of microwave irradiation in the quaternization of amino-functionalized MIL-53 metalorganic framework (MOF) as well as the catalytic activity of the resultant MOF in the cycloaddition of carbon dioxide with epoxides under solvent-free conditions has been studied. A series of NH2-MIL-53 were synthesized and quaternized by reacting alkyl...

The concept of bio-metal-organic framework (bio-MOF) catalysts for CO2 transformation was devised using l-glutamic acid as the natural surrogate for synthetic ligands, and demonstrated their catalytic efficacy for the first time, in the cycloaddition of CO2 with epoxides, supplemented with the structure-DFT correlation. The water stable amino acid...

A water stable zinc-MOF (ZnGlu) catalyst was facilely prepared from the proteinogenic amino acid, l-glutamic acid at room temperature in aqueous medium. CO2 fixations were promoted by the ZnGlu catalyst's inherently coordinated water and externally added water in yielding cyclic carbonate and cyclic urethane at room temperature. This eliminates the...

A novel approach of employing a dual-porous metal organic framework (MOF) in CO2 fixation at room temperature was demonstrated using a micro–mesoporous MOF, UMCM-1-NH2, in the synthesis of various five-membered cyclic carbonates under solventless conditions. Mesopores allow easy guest diffusion and molecular accessibility, while micropores are pred...

In this study, zeolitic imidazolate framework (ZIF-90) was synthesized from Zn(NO3)2·4H2O and imidazolate-2-carboxyaldehyde (ICA), then it was post-functionalized to form F-ZIF-90 using hydrazine followed by quaternization. The ZIFs were characterized by elemental analysis (EA), BET, XRD, 13C NMR, FT-IR, and SEM. The surface area and pore volume of...

The catalytic oxidation of hydrogen sulfide (H2S) in the presence of ammonia was studied over niobium pentoxide supported on Fe-pillared clay catalysts (Nb/Fe-PILCs). The synthesized catalysts were characterized by various techniques such as X-ray diffraction, BET method, X-ray photoelectron spectroscopy, temperature-programmed reduction, temperatu...

Cycloaddition of carbon dioxide and epoxides was investigated using zinc halide based Lewis acidic ionic liquids (ILs) as catalysts. ILs such as 1-butyl-3-methylimidazolium bromide (BMImBr), 1-butylpyridinium bromide (BPyBr), tetra-n-butylammonium bromide (TBABr) were mixed with zinc halide and supported on silica gel to produce heterogeneous catal...

Polystyrene-supported quaternized ammonium salt catalysts (PS-alkyl-AX) were synthesized and characterized by various physicochemical analytic methods such as EA, FT-IR, XPS, and SEM. The reactivity of the catalysts was investigated for the synthesis of allyl glycidyl carbonate from CO2 and allyl glycidyl ether under mild reaction conditions. The P...

An environmentally clean, binary catalytic system of naturally occurring α-amino acids (AAs)/H2O has been found to deliver promising yields of propylene carbonate (PC) from propylene oxide (PO) and CO2 under moderate reaction conditions. Among the various AA systems tested, the highest yield of PC from PO-CO2 coupling was achieved with the L-His/H2...

The synthesis of glycerol carbonate by glycerolysis of urea was investigated under mild conditions, using immobilized metal-containing ionic liquid catalysts. Three different catalysts were prepared, with the following supports: (1) polystyrene (PS), (2) commercial silica (CS), and (3) chitosan (CH). The glycerolysis of urea was considered to inclu...

This paper dealt with the propagation characteristics of acoustic signals produced by partial discharges and the positioning of PD origin in insulation oil to develop insulation diagnostic techniques of oil-immerged transformers. Electrode systems such as needle to plane, plane to plane, and particle electrodes were fabricated to simulate some defe...

In this study, we designed and fabricated the LED navigation lighting system which complements the disadvantages of conventional light and improves luminous performance. A 5.6 W LED module was fabricated to replace a 60 W incandescent lamp, and its diameter was minimized to dispose itself on the focal point of conventional lens. To improve heat rad...

Ionic liquids immobilized onto structurally modified polyethylene glycol (PEG) were prepared through the reaction of 1-(2-hydroxyl-ethyl)-3-alkyl-imidazolum chloride and PEG-succinic acid. Elemental analysis, SEM, C-13 NMR and FT-IR showed that the immobilized ionic liquid groups were well incorporated onto the PEG support. The PEG-supported ionic...

The catalytic oxidation of hydrogen sulfide over V2O5 supported on Al-pillared clay (V/Al-PILCs) was studied. The synthesized catalysts were examined using a variety of characterization techniques such as XRD, BET, XPS, 51V NMR, H2-TPR and NH3-TPD. A catalytic activity study performed by using V/Al-PILC catalysts showed that H2S was successfully co...

This paper dealt with the radiated electromagnetic wave detection of partial discharge (PD) in oil for insulation diagnostics of oil-immersed transformers. Three types of electrode system were fabricated to simulate the insulation defects that could occur in oil-immersed transformers. Frequency components of radiated electromagnetic wave in oil was...

In this study, various ionic liquids immobilized onto montmorillonite clay (IL-MMT) were prepared by ion-exchange reaction between the ionic liquids and ions in the clay interlayer. Tetra-alkyl ammonium chlorides were used as the ionic liquid precursors. The IL-MMTs were characterized by elemental analyses (EA), BET, XRD, 13C NMR, FT-IR, and SEM. T...

An efficient method of utilizing microwave irradiation for the quaternization of chitosan (QCHT) has been investigated. QCHT catalysts have been characterized by various physicochemical methods such as FT-IR, XRD, XPS, TGA, EDS, SEM, EA, and BET. They exhibited excellent activity for the solvent-free cycloaddition of CO2 and allyl glycidyl ether (A...

A novel attempt of using quaternized chitosan (QCHT) as a catalyst for the cycloaddition reaction of allyl glycidyl ether (AGE) and CO2 under solvent-free conditions has been made. The surface quaternization of CHT has been characterized by means of various physicochemical methods, such as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (...

In this study, tetraoctyl ammonium chloride (TOAC) ionic liquid supported on K+-montmorillonite clay (K10) was prepared by the adsorption of the ionic liquid onto the clay. The TOAC-K10 was characterized by elemental analysis (EA), BET, 13C NMR, 27Al NMR, SEM, TEM, and FT-IR. The surface area and average pore diameter of the TOAC-K10 decreased with...

This paper dealt with the measurement and analysis of electromagnetic waves generated by partial discharge (PD) in insulation oil to develop insulation diagnostic techniques for oil-immersed transformers. Two types of narrow-band monopole antennas with resonant frequency of 500 MHz and 1 GHz were designed and fabricated. Electrode system which cons...

The synthesis of dimethyl carbonate(DMC) is a promising reaction for the use of naturally abundant carbon dioxide. DMC has gained considerable interest owing to its versatile chemical reactivity and unique properties such as high oxygen content, low toxicity, and excellent biodegradability. In this study, the synthesis of DMC through the transester...

A double metal cyanide (DMC) complex based on (Zn3[Co(CN)6]2), an effective catalyst for the ring opening polymerization of epoxides and the copolymerization of carbon dioxide with epoxides, was successfully utilized for the solvent-free cycloaddition of CO2 to styrene oxide (SO) by the introduction of cetyltrimethylammonium bromide (CTAB) as a com...

Poly(ethylene oxide) (PEO)-based polymer electrolytes containing amorphous silica attached ionic liquid (IL) were studied in order to improve electrochemical and interfacial properties. An imidazolium salt such as IL was attached to modified ceramic fillers. The modified ceramic fillers were amorphous silica with the immobilized 1-methyl-3-propyl-i...

This paper proposes a reduced-scale simulator that can replace numerical analytic methods for the estimation of potential distribution caused by ground faults in various grounding systems. The simulator consists of a hemispherical electrolytic tank, a three-dimensional potential probe, a grounding electrode, and a data acquisition module. The poten...

This paper dealt with the fabrication of a partial discharge (PD) analyzer for insulation diagnosis of power facilities like transformers, cables and gas-insulated switchgears. An analytic algorithm for the phase (), the magnitude (q), and the pulse count (n) of PD pulse was designed and a time-frequency (TF) map algorithm was applied in the system...

This paper dealt with the frequency component analysis of acoustic signals produced by corona and series-arc discharges as a diagnostic technique for closed-switchboards. Corona and series-arc discharge were simulated by a needle-plane electrode and an arc generator specified in UL1699, respectively. Acoustic signal was detected by a wideband acous...

Ionic liquids (ILs) immobilized onto a structurally modified Merrifield peptide resin (MPR) were prepared through the reaction of imidazole with alkoxylated MPR. Elemental analysis and scanning electron microscopy (SEM) observations showed that the immobilized IL groups were effectively incorporated on the support. The MPR-supported ILs (MPR-ILs) p...

Bundle of CeO2 nanowires have been successfully synthesized by a simple hydrothermal process using Ce(NO3)3·6H2O as cerium source and NaH2PO4·2H2O as mineralizer, into which no surfactant or template was introduced. The synthesized nanowires were characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), ener...

The selective catalytic oxidation of hydrogen sulfide to elemental sulfur in a continuous-flow fixed-bed reactor was studied over V2O5-supported Fe-pillared clay (V/Fe-PILC) catalysts. The synthesized catalysts were characterized by X-ray diffraction (XRD), surface area–pore volume measurements, chemical analysis, X-ray photoelectron spectroscopy (...

We studied oxidative stress in cinnamon clownfish exposed to hypoosmotic (35 psu → 17.5 psu and 17.5 psu with prolactin (PRL)) and low temperature (28°C → 24°C and 20°C) conditions by measuring the expression and activity of Cu/Zn-superoxide dismutase (Cu/Zn-SOD), catalase (CAT), and glutathione peroxidase (GPX). The expression and activity of the...

Ship ballast water affects various marine species in a port or in a coastal area. The International Maritime Organization (IMO) adopted “the Convention on Ballast Water Management” in February 2004 and insisted that all ships be equipped with a ballast water treatment system beginning 2010. As basic study on a low power consumption ballast water tr...

This paper presents a comparative analysis on step and the touch voltages generated by either a sine and a ring wave voltage generator; this analysis was done as a basic study in order to develop a small and lightweight ground meter. A ring wave generator using pulsed power technology was fabricated; an experimental grounding system specified in In...

This study focuses on the selective catalytic oxidation of hydrogen sulfide (H2S) over vanadia supported on TiO2-pillared clay catalysts (V/Ti-PILCs) in the presence of ammonia and water. The synthesized V/Ti-PILC catalysts were characterized by chemical analysis, surface area/pore volume measurements, Fourier transform infrared (FTIR) spectroscopy...

In this paper, we dealt with the design and fabrication of a medium pressure ultra-violet (UV) lamp and a magnetic ballast which are main components for ballast water treatment systems (BWTS). To acquire an optimal discharge condition of UV lamp, electrical and optical characteristics depending on the argon gas volume and the amount of mercury were...

In this study, a series of imidazolium-based ionic liquids (ILs) having carboxylic acid moieties were synthesized and used as new homogeneous catalysts to synthesize cyclic carbonates from CO2 and epoxides. Even in the absence of any co-catalyst and organic solvent, carboxylic-acid-functionalized ILs showed better catalytic activity in the coupling...

A series of carboxyl-group-functionalized imidazolium-based ionic liquids (CILs) were synthesized and grafted onto silica gel. The catalytic activity of the resulting heterogeneous catalysts toward the synthesis of cyclic carbonatevia cycloaddition reactions of epoxide and CO2 was studied. The effect on the reaction of the grafted ILs' structures a...

Ionic liquids on ordered mesoporous silica were prepared and their catalytic performance in the synthesis of dimethyl carbonate (DMC) was investigated. The ionic liquids were immobilized on chloropropyl-functionalized MCM-41 (CP-MS41) through the quaternization of trialkylamines. The supported ionic liquids were proven to be an effective heterogene...

Ionic liquids immobilized onto structurally modified Merrifield peptide resin (MPR) were prepared through the reaction of imidazole with alkoxylated MPR. Elemental analysis and SEM images showed that the immobilized ionic liquid groups were well incorporated onto the support. The MPR-supported ionic liquids (MPR-IL) proved to be effective heterogen...

Microwave-assisted cycloaddition of CO2 to phenyl glycidyl ether (PGE) was carried out under solvent-free conditions using silica-supported ionic liquids as catalysts. Various immobilized ionic liquid catalysts were prepared with different silica supports such as commercial and amorphous silica, SBA-15, and MCM-41. The effect of these supports on t...

Highly cross-linked porous poly(N-vinylimidazole-co-divinylbenzene) (PVIm) beads of various pore sizes and specific surface areas were synthesized by suspension polymerization. The surfaces of the PVIm beads were then modified with various alkyl halides to obtain various ionic liquid-grafted porous polymer beads (PVIm-RX), which were then used as h...

In this study, we analyzed the frequency spectrum of the electromagnetic waves radiated by an electric discharge as a basic method for developing an on-line diagnostic technique for power equipment installed inside closed-switchboards. In order to simulate local and series discharges caused by an electric field concentration and poor connections, t...

In this paper, we performed an insulation diagnosis technique for oil-immersed power transformers by an acoustic detection method. Electrode system such as needle to plane electrode was fabricated to simulate a defect of power transformers. In addition, the frequency spectrum of acoustic signals with partial discharge (PD) in insulating oil was ana...

This paper dealt with the design, fabrication and application of a risk voltage measurement system (RVMS) which analyzes the step and touch voltages in electrical grounding systems. The RVMS supply 300 V and 1.4 A in ranges from 40 Hz to 1 kHz as the test power source. A DAQ module having resolution of 400 kS/s and 16 bit is equipped with 7 inputs...

A variety of imidazolium-based ionic liquids (ILs) have been widely developed to effectively catalyze the cycloaddition reactions of CO2 and epoxides. To further improve the catalytic performance of those IL catalysts, we incorporated various metal chlorides (CoCl2, NiCl2, CuCl2, ZnCl2, and MnCl2) into silica-grafted 1-methyl-3-[(triethoxysilyl)pro...

A series of vanadia-doped iron-oxide-pillared clays (V/Fe-PILCs) with various amounts of vanadia were prepared and their performance for the selective catalytic oxidation of H(2)S was investigated. V/Fe-PILCs were characterized using X-ray diffraction (XRD), surface area- and pore volume measurements, chemical analysis, Fourier-transform infrared (...

The basic performance of the ground system is evaluated as the ground resistance by applying low frequency current below 1 kHz. However, characteristics of the ground system should be analyzed by high frequency current up to 1 MHz since transient currents having a few hundred kHz component flow during a line-to-ground fault and/or a lightning strik...

In this paper, we studied the application of low pressure ultra-violet (UV) lamps for the development of an energy saving ship's ballast water treat (BWT) device. We proposed the optimal arrangement of UV lamps by analyzing the energy radiated from medium- and low-pressure UV lamps. Based on the experimental results, we manufactured a disinfection...

The absorption rate (RA ) of carbon dioxide was measured into an aqueous nanometer-sized colloidal silica solution of 0–31 wt% and NaOH of 0–2 kmol/m3 in a flat-stirred vessel for various sizes and speeds of 25 °C and 101.3 N/m2 to obtain the volumetric liquid-side mass transfer coefficient (kL aL ) of CO2. The film theory accompanied by chemical r...

Ionic liquid immobilized on commercial silica catalysts proved to be an effective heterogeneous catalyst for the synthesis of dimethyl carbonate (DMC) from transesterification of ethylene carbonate (EC) with methanol. The immobilized 1-n-alkyl imidazolium halide ionic liquid on commercial silica (RImX-CS) was characterized by EA, BET, FT-IR, 13C NM...

In this study, ionic liquids immobilized on mesoporous MCM41 were prepared and their catalytic performance was tested in the synthesis of glycerol carbonate from transesterification of ethylene carbonate with glycerol. The ionic liquids were generated on chloropropyl functionalized MCM41 (CP-MCM41) via the immobilization of trialkylamines. The quat...

In the present work, titania-pillared clay (Ti-PILC) and zirconia-pillared clay (Zr-PILC) were synthesized, and their catalytic performance was studied for the selective oxidation of H2S to elemental sulfur. The obtained pillared clays (PILCs) were characterized by X-ray fluorescence spectroscopy (XRF), infrared (FTIR) spectroscopy, BET surface are...

In this paper, we analyzed the frequency spectrum of radiated electromagnetic pulses generated by series arc- and corona- discharges as a basic study to develop an on-line diagnostic technique for power facilities installed inside closed-switchboards. To simulate series arc and corona discharges, five types of electrode system which consists of nee...

A series of zirconium-doped nano-titania (Zr/TiO(2)) with various amounts of Zr were prepared by sol-gel method using titanium(iv) isopropoxide and zirconium nitrate as precursors. Zr/TiO(2) samples were characterized using X-ray diffraction (XRD), surface area-pore volume measurements, infrared (FTIR) spectroscopy, UV-vis-diffuse reflectance spect...