Proses Penghasilan Bromelin daripada Batang Nenas

A proteolytic enzyme called bromelin can be produced from pineapple stem by precipitating it from pineapple stem juice and separating the precipitate from the juice. Acetone is used as the precipitant. The precipitating process is performed twice and the second precipitate is taken as the bromelin product. This process is not well understood and is not amenable to mathematical modelling. The main aim of the present study is to identify process variables such as the precipitant: juice ratio, precipitation time and centrifugation time in every stage which have a significant effect on the yield and activity of bromelin. Factor analysis is used. This study found that the centrifugation times in both stages, precipitation and centrifugation times in the second stage affect the yield of bromelin. The enzyme activity is affected by the precipitant: juice ratio, the precipitation and centrifugation times in the first stage,' precipitant: juice ratio and precipitation time in the second stage. This process is currently being optimised

ANALYSIS OF CAPITAL STRUCTURE AND FINANCIAL PERFORMANCE IN THE JORDANIAN INSURANCE SECTOR

Purpose of the study: This paper aims to examine the impact of capital structure and financial performance of listed insurance companies in Jordon. Methodology: This study used secondary data that was collected from Amman stock exchange and annual report of the selected insurance companies from the year 2007-2017. The static panel data analysis technique is used to examine the impact of capital structure on firm’s performance. The capital structure is measured using short-term debt, long-term debt, and equity financing. Whereas financial performance is measured using Return on Asset (ROA), Return on equity (ROE), and Tobin’s Q. Main Findings: The study findings suggest that capital structure influence the profitability of the listed insurance firms in Jordan. The results also reveal a significantly positive relation between long-term debt to total assets to profitability indicators, namely, return on assets (ROA), return on equity (ROE) and Tobin’s Q. On the other hand, the results also reveal a short-term debt has a significant positive relationship with return on equity (ROE) and returns on assets (ROA). However, a relationship between short-term debt and Tobin’s Q is not statistically significant. Applications of this study: The result of this study may assist the insurance sector in Jordon in making decisions regarding capital structure, which is to significantly rely on equity financing or debt financing to reduce financing risk such as agency cost that borne by the equity holders of the Jordanian insurance firms. Novelty/Originality of this study: The study noted that insurance firms generally play a crucial role in the economic development of every country. This study provides evidence that Jordanian insurance firms need to diversify their sources of financing and not rely significantly on debt financing, as the results prove that equity financing is a profitable source of financing

Synthesis and optical properties of ZnO-TeO2 glass system

Problem statement: Systematic series of ZnO-TeO2 glasses with mole fraction of 0.10-0.40 ZnO content with an interval of 0.05 were studied to obtain their physical and optical properties. Approach: All the glass samples were synthesized by rapid melting quenching method under controlled conditions, while their refractive indices (n) were measured by the EL X-02C high precision ellipsometer. The room temperature absorption of all glass samples were determined using Camspec M350 double beam UV-visible spectrophotometer. The infrared (IR) spectra of each glass samples were recorded with Thermo Nicolet Fourier Transform-Infrared (FT-IR) spectrophotometer. Their physical properties were measured and the amorphous nature was confirmed by the x-ray diffraction technique. Results: The increase of refractive index of the TeO2-ZnO glasses with the addition of ZnO was best explained in terms of either electron density or polarizability of the ions. The absorption edge shift to higher energy (shorter wavelength) with increasing ZnO content was observed in this glass. The optical band gap (Eopt) of zinc tellurite glass decreases with increasing of ZnO content probably due to the increment of Non-Bridging Oxygen (NBO) ion contents which eventually shifted the band edge to lower energies. Conclusion/Recommendation: The physical and optical properties of zinc tellurite glasses were found generally affected by the changes in the glass composition. FTIR spectra of zinc tellurite glass revealed broad, weak and strong absorption bands in the investigated range of wave numbers from 4000-400 cm-1 which associated with their corresponding bond modes of vibration and the glass structure. The addition of ZnO into TeO2 glass network shifted the major band from 626 cm-1 (for pure TeO2 glass) to the band at around 669 cm-1

Photopyroelectric measurement of thermal diffusivity of solids based on the theory of thermal wave interferometry

A standard photopyroelectric configuration was used for the measurement of thermal diffusvity of solids by considering the phenomena of thermal wave interference. The thermal wave generated within the samples will be partially reflected and transmitted upon striking at the medium boundaries. The effect of infinite multiple reflection of the thermal wave within the samples was extensively discussed by Bennett and Patty in the generation of photoacoustic signal. In this work where sample surface heating was assumed and a thermally thick condition was applied, only one thermal wave reflection back into sample was considered, that is by the top pyroelectric coating, but with a series of transmitted wave into pyroelectric film from the upper and the lower pyroelectric-coating interface in the generation of photopyroelectric signal. A normalisation procedure was used to eliminate the number of unnecessary parameters needed to be known before one can determine the thermal diffusivity of the sample. With the appropriate sample-pyroelectric detector dimension, the thermal diffusivity of any solid sample is readily being determined. The method was experimentally tested for aluminum, copper, and nickel, and the values obtained were close to the literature values

Development of Hybrid PV Wind Harvesting Energy for Electric Vehicles

The technology of electric vehicles (EV) is conventionally using battery to operate the motor. However it has one major disadvantage on energy storage capacity. Basically the battery needs to be recharged every day at the charging station which usually takes hours to fully charged. In this paper, the concept of battery charging using the hybrid PV-Wind for electric vehicles energy source is presented. The prototype of photovoltaic (PV) and wind energy harvesting has been developed to overcome this problem in the most effective way. This prototype will harvest the energy from both PV and wind to recharge the battery in electric vehicles so that the car can travel in longer time and distance. Three experiments have been conducted to analyze the best system namely PV system, wind generator system and hybrid PV wind system. Based on the experiment that has been carried out, it can be concluded that the hybrid PV wind system is the best compared to the other two because the current generated by hybrid PV wind is the highest which is 1A compared to 0.51A by PV system and 0.67A by wind system, respectively. The high current value is significantly means that the time taken to fully charge the battery is faster and this will lead to decrease the time used for the charging process

Development of hybrid PV wind harvesting energy for electric vehicles

The technology of electric vehicles (EV) is conventionally using battery to operate the motor. However it has one major disadvantage on energy storage capacity. Basically the battery needs to be recharged every day at the charging station which usually takes hours to fully charged. In this paper, the concept of battery charging using the hybrid PV-Wind for electric vehicles energy source is presented. The prototype of photovoltaic (PV) and wind energy harvesting has been developed to overcome this problem in the most effective way. This prototype will harvest the energy from both PV and wind to recharge the battery in electric vehicles so that the car can travel in longer time and distance. Three experiments have been conducted to analyze the best system namely PV system, wind generator system and hybrid PV wind system. Based on the experiment that has been carried out, it can be concluded that the hybrid PV wind system is the best compared to the other two because the current generated by hybrid PV wind is the highest which is 1A compared to 0.51A by PV system and 0.67A by wind system, respectively. The high current value is significantly means that the time taken to fully charge the battery is faster and this will lead to decrease the time used for the charging process

Electrical conductivity studies in polycrystalline (CuSe)1-xSex

This studies are directed towards measuring the electrical conductivity of the (CuSe)1-xSex metal chalcogenide semi-conductor composites, with different stoichiometric compositions of Se (x = 0, 0.2, 0.4, 0.5, 0.6, 0.8,1.0) in bulk form. The electrical conductivity measurement was carried out at room temperature, using the parallel plate technique. The (CuSe) 1-xSex composites were prepared using solid state reaction, by varying the ratio of CuSe:Se, in the reaction mixture. The electrical conductivity of (CuSe) 1-xSex was determined to be in the range of 1.17 x 10-8 to 1.02 x 10-1 S/cm. The finding indicated that the electrical conductivity value tended to decrease as the concentration of Se increased. The effect of the concentration of Se, on electrical conductivity of (CuSe) 1-xSex composites, is discussed in this paper