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The purpose of this paper is to introduce bio-inspired FeN₄-S-C black nano-electrocatalyst for the oxygen reduction reaction (ORR) in an alkaline medium. The FeN₄-S-C derived without pyrolysis of precursors in high temperature is recognized as a new electrocatalyst for the ORR in an alkaline electrolyte. For the proper design of bio-inspired nano-electrocatalyst for the ORR performance, chlorinated iron (II) phthalocyanine nanoparticles were used as templates for achieving the active sites in aqueous KOH by rotating disk electrode methods. The most active FeN₄-S-C catalyst exhibited a remarkable ORR activity in the alkaline medium. The objectives of this paper are to investigate the possibility of nanoscale particles size (Ëœ5nm) of electrocatalyst, to achieve four-electron transfer mechanism and to exhibit much superior catalytic stability in measurements. This paper will shed light on bio-inspired FeN₄-S-C materials for the ORR catalysis in alkaline fuel cells.

The paper presents a new bio-inspired nano-electrocatalyst for the ORR, which has activity nearby platinum/carbon electrocatalyst. Chlorinated iron phthalocyanine nanoparticles have been used as FeN₄ template, which is the key point for the ORR. Bio-inspired nano-electrocatalyst has been fabricated using chlorinated iron phthalocyanine, sodium sulphide and carbon black.

The particles’ size was 5 nm and electron transfer number was 4.

The catalyst that is used in this method should be weighed carefully. In addition, the solvent should be a saturated solution of NaCl in water.

The method provides a simple and practical solution to improving the synthesis of iron-based catalyst for ORR.

The method for the synthesis of bio-inspired electrocatalyst was novel and can find numerous applications in industries, especially as ORR non-precious metal catalyst.

Environmental issues and lack of drinking water have forced researchers to find some alternatives to wastewater treatment. Because dyes are used in a variety of industrial applications such as textile and pharmaceutical, wastewater of these factories leads to several environmental problems. Using catalysis under ultraviolet-irradiation (photocatalysis) is one of the cases that is used in wastewater treatment. The purpose of this work is the photocatalytic degradation of dye (Reactive Red 198) and pharmaceutical (tetracycline) using MIL-53(Fe) and MIL-100(Fe).

In this work, Reactive Red 198 (RR198), an anionic dye and tetracycline as a pharmaceutical are tested with two catalysts, MIL-53(Fe) and MIL-100(Fe). Catalyst synthesis method and characterization were discussed by X-ray diffraction, scanning electron microscopy and Fourier Transform Infrared analyses, and their results are described in detail.

Dye concentration varies among 15, 20, 30 and 40 mg/L for MIL-100(Fe) for which the removal percent is 97%, 94%, 89% and 58% and for MIL-53(Fe), dye concentration increases from 20 to 40, 60 and 80 mg/L, the removal percent of which is 98%, 88%, 75% and 50%. Pharmaceutical degradation by MIL-53(Fe) and MIL-100(Fe) was 75% and 80%, respectively.

Photocatalytic degradation of RR198 and tetracycline using MIL-53(Fe) and MIL-100(Fe) was not studied in detail.

A structural and textural characterization study has been performed to investigate the adherence of zeolite-based catalyst washcoated onto honey-comb-type cordierite monoliths. The supports were characterized by the scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS), X-ray diffraction (XRD) and Brunauer–Emmett–Teller (BET) techniques.

SEM/EDS provided quantitative estimate of the washcoated monolith as the elemental composition of catalyst coating. The XRD pattern deduced that the zeolite-based catalysts were successfully mounted on the cordierite support, showing the characteristic peaks of zeolites (Zeolite Socony Mobil–5; ZSM-5) at Braggs angles of 7.88°, 8.76°, 23.04°, 23.88° and 24.36°, whereas the characteristic peak of cordierite is seen at a Braggs angle of 10.44°.

The BET results proved that a monolayer of zeolite may serve the need for surface area and porosity. This was evident in the increase of surface area of washcoated support as against the bare support. The obtained isotherms were of Type IV, illustrating the presence of mesopores. The adsorption and desorption isotherm branches coincided over the interval 0 < P/P0 < 0.50 and 0 < P/P0 < 0.45, showing N₂ reversible adsorption for the two samples, respectively.

It was concluded that the composite materials which are ZSM-5 (Si/Al = 25) and precursors of the transition salts of copper, zinc and ceria powders were deposited on the catalyst supports, establishing the success of the coating procedure relative to the adherence of the catalyst compositions on the ceramic support.

This paper aims to address the polymerization of 1-decene by [Emim]Cl/AlCl₃ ionic liquid and the film-forming properties of the product compared with commercially available base stocks.

Experiments were carried out to investigate the influence of [Emim]Cl/AlCl₃ mole ratio, catalyst dosage, reaction temperature, reaction time and water on the polyreaction. Poly alpha-olefin (PAO) is prepared under optimal reaction condition. Film-forming properties of PAO have been compared with those of Group I, Group II and Group III base stocks, which are selected with approximately the same viscosity.

Experimental results show that after a 4-h reaction time, yield of PAO can be higher than 85 per cent and viscosity index can be up to 160 with [Emim] Cl/AlCl₃ mole ratio of 2:1, catalyst dosage of 3 per cent wt. and water content of 20 ppm. A strong influence of water on reaction is observed. With approximately the same viscosity, PAO shows the superiority in film thickness at low-sliding speeds compared with Group I and Group II base stocks. At high temperature, PAO provides a thicker film than other base stocks.

In recent years, there has been considerable interest in ionic liquids. As a novel catalyst, it has so many advantages including low corrosion, low toxicity, low cost and a potentially wide range of properties compared with traditional catalysts. This paper reports the polymerization of 1-decene by [Emim]Cl/AlCl₃ ionic liquid and the study on lubricating properties of PAO compared with mineral base stocks.

Public finance watchdogs and guardians of the public purse. These are just two of the labels branded on Auditors General over the years. Since their initiation into value for money audit only three decades ago, they have continually been exposing cases of public financing laxity. Each time the auditors approach a government organization, their reputation invariably precedes them. But what happens when the controllers decide to turn over a new leaf and become catalysts for change and improvement who have come to help managers improve their public organizations? Auditees, totally unaccustomed to seeking help from auditors, are understandably befuddled. On the other side of the coin, auditors are equally inexperienced at providing assistance to auditees. There is many a slip twixt cup and lip before the role confusion dissipates.

The aim of this study is the synthesis and characterization of motor and hydraulic oils based on complex esters of dicarboxylic acids and polyol esters. The esters have been prepared by polyesterification of adipic or sebacic acids with polyethylene glycol and by subsequent reaction with 2‐ethylhexanol using a new high active catalyst tetraoktyltitanate (TOT)‐TlCl. The synthesis of pentaerythritol esters of monocarboxylic acids has also been undertaken in the presence of the same catalyst. The catalyst reduces the time and temperature required for the reaction to produce esters with characteristics of standard motor and hydraulic oils.

The purpose of this paper is to numerically investigate the effects of the shape on the performance of the cathode catalyst agglomerate used in polymer electrolyte fuel cells (PEFCs). The shapes investigated are slabs, cylinders and spheres.

Three 1D models are developed to represent the slab like, cylindrical and spherical agglomerates, respectively. The models are solved for the concentration of the dissolved oxygen using a finite element software, COMSOL Multiphysics®. “1D” and “1D axisymmetric” schemes are used to model the slab like and cylindrical agglomerates, respectively. There is no one-dimensional scheme available in COMSOL Multiphysics® for spherical coordinate systems. To resolve this, the governing equation in “1D” scheme is mathematically modified to match that of the spherical coordinate system.

For a given length of the diffusion path, the variation in the performances of the investigated agglomerates is dependent on the operational overpotential. Under low magnitudes of the overpotentials, where the performance is mainly limited by reaction, the slab-like agglomerate outperforms the spherical and cylindrical agglomerates. In contrast, under high magnitudes of the overpotentials where the agglomerate performance is mainly limited by diffusion, the spherical and cylindrical agglomerates outperform the slab-like agglomerate.

The current advances in the nano-fabrication technology gives more flexibility in designing the catalyst layers in PEFCs to the desired structures. If the design of the agglomerate catalyst is to be assessed, the current micro-scale modelling offers an efficient and rapid way forward.

The current micro-scale modelling is an efficient alternative to developing a full (or half) fuel cell model to evaluate the effects of the agglomerate structure.

Lauroyl peroxide can be produced by reaction of lauroyl chloride with hydrogen alkali metal peroxides, e.g. it can be produced by treatment of lauroyl chloride with hydrogen peroxide and potassium hydroxide. It has also been prepared by reacting a mixture of lauroyl chloride, lauric anhydride and phosphorous trichloride in benzene, with a mixture of hydrogen peroxide, water, sodium phosphate and caustic soda. It can be dried in the form of an emulsion by centrifuging.

This study focused upon the role, function and scope of the financial management systems operating in the small business sector of the economy. The research sought to understand why in certain firms robust financial systems exist whereas in others they are seen to be weak. To this end the role of the accounting profession as it effects financial management systems was investigated. The study produced some interesting results. Bookkeeping systems adopted for financial accounting scored positively which may well be linked to the high preponderance of integrated computer systems adopted by firms. Management accounting systems did not score as well as financial accounting overall. Whilst smaller businesses were most likely to be dissatisfied with their management accounting systems, long established firms were as likely to be dissatisfied with their financial and management accounting systems than more recently established entities.

This study aims to investigate the coupling reaction of epoxide and CO₂ catalysed by alkali metal salts in the presence of ß-cyclodextrin (ß-CD) derivatives to generate cyclic carbonates at various conditions.

The coupling reaction was catalysed by alkali metal salts. The effects of the co-catalysts were investigated by using the conversion rate of raw materials. The affecting factors, such as reaction temperature, amount of the co-catalyst and reaction time, were explored. The possible mechanism of the coupling reaction was discussed.

Results showed that the structure of ß-CD is an important factor influencing the catalytic activity for the coupling reaction of epoxide with CO₂. The catalytic system of 2,3,6-trimethyl-ß-CD with potassium iodide (KI) showed a high catalytic activity. The protocol was expanded to various epoxides, which provided the corresponding cyclic carbonates in excellent yields. The apparent decrease in the yields was not detected after four recycling times. Moreover, the mechanism for the synergetic effect of the catalyst was proposed.

The coupling reactions were achieved in the presence of different structure of ß-CD as co-catalysts. The affecting of substituent of ß-CD were investigated.