Enzymatic Synthesis of Oleyl Oleate, a Liquid Wax Ester, in a Stirred Tank Reactor

High performance enzymatic synthesis of oleyl oleate, a liquid wax ester was successfully synthesized via enzymatic esterification reaction of oleic acid and oley alcohol. Immobilised Candida antartica lipase B (Novozym 435) was used as biocatalyst. The study was divided into four parts which are the optimisation of reaction synthesis at different scales, the reactor study in term of mixing efficiency, the stability of immobilised enzyme and the analysis and characterization of the product of the reaction. Preliminary synthesis of oleyl oleate was carried out in a small scale reaction with a total volume of 3.5 mL using screw-capped vials. Optimisation reaction study via conventional method of varying one parameter at-a-time approach was carried out. A high percentage conversion yield of >90% was achieved at optimum reaction time of 5 min, reaction temperature of 40-6O0C1 molar ratio of substrates (oleyl alcoholloleic acid) of 2:1, amount of enzyme of 0.4 g and organic solvents of Log P23.5 at fixed agitation speed of 150 rpm. Investigation in larger scale production of oleyl oleate was performed using 2 L stirred tank reactor (STR). The reaction was scaled-up to 300X with a total volume of 1.05 L. A high percentage conversion of oleyl oleate was achieved of >95% by conventional experiment method at reaction time of 30 min, agitation speed of 400 rpm, reaction temperature of 45-50°C, molar ratio of substrate (oleyl alcoholloleic acid) of 2:l and amount of enzyme of 90 g. The reaction synthesis was further optimised by response surface method (RSM) based on five-level, three-variable central composite rotatable design (CCRD) to evaluate the interactive effects of important parameters in larger scale processing. Generally, simultaneously increasing amount of enzyme, agitation speed and reaction temperature would improved the yields. A high percentage conversion of 97.4% was achieved under the optimum condition, which compared well with the maximum predicted value of 97.7%. In order to improve the production and productivity of oleyl oleate to the highest amount that can be produced in a 2 L STR, the reaction was synthesized in a solvent-free system. Maximum scaling-up of substrate concentration that can be achieved in the reactor vessel was 900X as compared to 300X previously. The production and productivity of oleyl oleate were successfully improved from 295.39 g/L/h to 705.76 g1Uh and 31 0.16 glh to 952.78 glh, respectively. Reactor study on the performance of 2 L STR as a mixing device was evaluated to improve the mixing efficiency. The rheological property of the reaction mixture exhibited Newtonian behaviour. Rushton turbine impeller showed better performance in degree of mixing, as compared to AL Hydrofoil impeller whereby a high Reynolds number of >lo4 was achieved at 400 rpm, which exhibit a turbulent flow pattern. There was significant effect to the mixing improvement on the enzyme particles distribution by using a 2 impellers system with spacing of 30 mm. The enzyme showed high stability against heat as shown by the high percentage conversion of wax ester. Novozym 435 retained its synthetic activity up to 9 uses and 4 uses in screw-capped vials and STR, respectively. The effect of shear forces due to the mechanical agitation speed on the enzyme morphology was determined by scanning electron microscope (SEM). Although small rupture on the surface of enzyme was observed when increasing the agitation speed, the enzyme activity was very high even at high agitation speed.Analysis of product was evaluated by spectroscopy method of Fourier transform-infrared spectroscopy (FT-IR) and gas chromatography-mass spectroscopy (GC-MS) to identify the product obtained. Characteristics of oleyl oleate were also examined, which include iodine value, saponification value, acid value and ester value. Solubility of oleyl oleate in methanol and ethanol was comparatively lower as compared to the solubility at higher chain length of alcohols. This compound seems compatible in most of oils and stable even after heating up to 90°C and overnight storage at room temperature

Identifying Business Potential for Small and Medium-Sized Enterprises (SMEs) Based on Developmental Plans in Penang, Malaysia

This study aims to identify the business potential possibilities for small and medium-sized enterprises (SMEs) and explore the ways in which such businesses and state, regional and national economic development planning may interact. Drawing insights from Penang’s development plans and/or blueprints, this paper generates a typology of such plans and maps them accordingly in terms of economic sector. In capturing the national and state development plan and/or policies for its economic progress, research methodology through a content analysis was done by referring to the documents issued by Penang and national agencies The strategies will help equip a way forward for SMEs to grow in response to these development plans. By participating in the main economic sectors this strategy will directly bring benefits for SMEs’ as they will be able to have wider access to markets, including government programs and incentives. When SMEs align their business model with what an economy is trying to achieve policy-wise, this endeavor will to a certain extent mitigate the common challenges that hinder SMEs’ growth

Determinants of Effective Financial Risk Management in Small Business: A Theoretical Framework

This paper aims to develop a theoretical model of potential determinants of effective financial risk management in small business. In achieving this objective, the methodology used includes library search and analyzing previous literature review on the subject of financial risk management and small business especially in Malaysia case study. The significant variables are namely the leadership, training programs, use of technology, entrepreneurship orientation (EO) and accounting information. This paper also hopes to strengthen the body of knowledge on how financial risk management helps small business towards success, besides to act as a reference for empirical research

Are sukuk debt or equity? A classification of sukuk by regulatory bodies and credit rating agencies / Rafisah Mat Radzi and Nurul Aini Muhamed.

Sukuk (Islamic bonds) are the Shariah (Islamic law) instrument that serves as an alternative to conventional bonds that are used in the modern capital market. In theory, sukuk represent a form of equity as they represent certificates conferring ownership to holders of an asset or pool of assets or claim to its cash flows. In practice, they have become known as Islamic bonds with their investors holding debt. Following the question of whether sukuk are debt or equity, this paper aims to classify sukuk from the perspective of regulatory bodies and credit rating agencies. Furthermore, to what extent the innovations in this Islamic instrument make it differ substantially from conventional bonds in practice will be examined

Design and Analysis of ‘Eco’ Car Chassis

Abstract‘Eco-Challenge’ race cars are built for fuel efficiency which means they must be lightweight and have low frictional resistance. However they are still subjected to normal car loading such as engine and driver weight, acceleration, braking and cornering forces. The challenge is to develop a lightweight chassis that can safely withstand the required loads. In addition, the chassis must also be able to protect the driver in the event of crash. A steel space frame was chosen for the design since it is the most effective and cost efficient structure and commonly used for single seater car. FEA was used to determine the strength and rigidity of the chassis subjected to the required loads. Results showed that chassis was able to withstand the required loads with minimal deflections

Asas perhubungan elektronik

Buku ini ditulis bertujuan untuk menjelaskan aspek-aspek asas yang penting dalam memahami sesuatu sistem perhubungan elektronik. Beberapa jenis sistem perhubungan yang umum dihuraikan dalam bentuk yang mudah untuk difahami. Ini meliputi sistem radio, televisyen, penghantaran isyarat digit dan rangkaian komputer. Kandungan buku ini telah disusun sebagai bahan pengajaran bagi pelajar peringkat Sarjana Muda Sains Industri (Fizik) di Fakulti Sains, Universiti Teknologi Malaysia. Walaupun begitu, buku ini dapat juga dijadikan sebagai bahan asas bagi kursus kejuruteraan lain, terutamanya Kejuruteraan Elektrik Perhubungan di peringkat universiti, kolej dan politeknik

Entrepreneurial Orientation, Psychological Capital, Entrepreneurial Strategy, and Firm Performance on Private Daycare in Indonesia: A Conceptual Paper

This paper aims to develop a conceptual model of the nexus of entrepreneurial orientation, psychological capital, entrepreneurial strategy, and firm performance in private daycare in Indonesia. This paper develops a conceptual model to look at the performance of daycare businesses in Indonesia based on a literature review by integrating relevant theories (such as entrepreneurial orientation, entrepreneurial strategies, and psychological capital) and logical reasoning. Research hypotheses are given to stimulate follow-up research. Based on the conceptual model, improving the performance of daycare business can be accomplished by the influence of the dimensions of entrepreneurial orientation, the role of business strategy mediation, and the moderation of psychological capital. It is hoped that empirical studies will be conducted to validate the relationship and interrelationships between related concepts and constructs in providing practical implications in the daycare business

Entrepreneurial Orientation, Psychological Capital, Entrepreneurial Strategy, and Firm Performance on Private Daycare in Indonesia: A Conceptual Paper

This paper aims to develop a conceptual model of the nexus of entrepreneurial orientation, psychological capital, entrepreneurial strategy, and firm performance in private daycare in Indonesia. This paper develops a conceptual model to look at the performance of daycare businesses in Indonesia based on a literature review by integrating relevant theories (such as entrepreneurial orientation, entrepreneurial strategies, and psychological capital) and logical reasoning. Research hypotheses are given to stimulate follow-up research. Based on the conceptual model, improving the performance of daycare business can be accomplished by the influence of the dimensions of entrepreneurial orientation, the role of business strategy mediation, and the moderation of psychological capital. It is hoped that empirical studies will be conducted to validate the relationship and interrelationships between related concepts and constructs in providing practical implications in the daycare business

The relationship between learning style and writing performance of young learners in PowerPoint assisted classes

This paper discusses the correlation between young learners’ writing performance and their learning styles when PowerPoint was used in teaching writing skills. This study focuses on the sensory learning styles which comprises visual, auditory, kinesthetic and tactile learning styles (perceptual learning style). Reid’s (1995) ‘Perceptual Learning Style Preferences’ questionnaire was used to ascertain the students’ learning styles and a correlation analysis between their learning styles and writing performance was run. The analysis shows that there is no statitistically significant difference between the writing performance of the young learners in computer-assisted class and the traditional class. Their learning styles did not have a significant influence on their performance