Reinforcement of Lime Ash Particles in LDPE - Pages 119-123

^{N. Khan, Z. Ahmed, M.A. Wasif and A. Nafees}

https://doi.org/10.6000/1927-5129.2018.14.17

Published: 6 April 2018

Abstract: This study presents findings from an experimental investigation on the reinforcement of Lime ash particles (LAP) synthesized from coal fly ash, CaO, and CaSO₄ in Low density Polyethylene (LDPE).

The Lime ash particles are synthesized by reinforcing 0 to 30 weight percentages of LAP in virgin LDPE using compression moulding. The mechanical properties of composites are studied and results showed that by adding LAP in LDPE as filler the Tensile Strength and Impact Strength of the composite decreases due to poor interfacial bonding between filler particles and LDPE but Hardness and Flexural Properties increases due to improved properties of surface.

Keywords: Lime ash particles, fillers, reinforcement, LDPE, polymer.

Review of Pharmacological Activities of Vetiveria zizanoide (Linn) Nash - Pages 235-238

Saroosh Zahoor, Sammia Shahid and Urooj Fatima

https://doi.org/10.6000/1927-5129.2018.14.36

Published: 22 June 2018

Abstract: Vetiveria zizanioides (Linn) Nash is a perennial magical grass of family poaceae commonly known as Khas which is highly valued grass due to its adventitious root system. It is widely distributed in the Pakistan. It is cultivated in all provinces of Pakistan due to its great economic importance. This grass grows plain ascending up to 1200m. Mostly roots stem and leaves were used for treatment of different diseases by ancestors. Adventitious roots contain essential oil which used for multipurpose such as perfumery and in pharmacological industry. Vetiver oil contains approximately 150 compounds, including sesquiterpenoide, hydrocarbons. Phytochemical analysis of leaves shows the presence of flavonoides, saponins, tannins and phenols. Various tribes of India used this tuft grass for commercial purposes. Khas serve as broom, for cooling, roof of huts and as medicine for different diseases such as sunstroke, ulcer, fever, epilepsy and in skin diseases. In this study we summaries the magical pharmacological activities of Vetiveria zizanioides such as anti inflammatory, antibacterial, antifungal, and anti malarial, anti tubercular, anti hyperglycemic, anti hepatoprotective and antioxidant activity.

Keywords: Pharmacological activities, Khas, perfume, traditional medicine, biodiversity.

Relation between Luminosity and Surface Rotation of Spotted Stars- Pages 1-8

^{Ingila Rahim1 and Muhammad Rashid Kamal Ansari}

https://doi.org/10.6000/1927-5129.2018.14.01

Published: 2 February 2018

Abstract: This communications explores the existence of a possible relationship between Luminosity and surface rotation for the study of the evolution of spotted stars using the data of Kepler’s and DI spotted stars. For the determination of such a relationship between luminosity and rotation the dependency of rotational shear on effective temperature is to be reviewed first. The strong dependence of rotational shear on the effective temperature in the range of 3000K and 6000K is confirmed by a power law. This dependence in turn introduces rotation as an evolutionary parameter for the study of the evolution of spotted stars. Multivariate Linear regression, Log-Log multivariate and Nonlinear Multivariate (2, 2) Degree models are constructed to determine the Luminosity of Kepler’s and Doppler imaging spotted stars with rotational shear, relative differential rotation and radius as independent variables. In this regard Log-Log model and Nonlinear Multivariate (2, 2) Degree model is best suited as compared to the linear model. In the next stage Log-Log model is applied to the main sequence Kepler’s stars (excluding giants) and also to the stars in the individual spectral classes A, F, G, K, and M. The model appears best for main sequence stars and also for the stars in the individual classes F-M. Applying the model on DI spotted stars the standard errors indicate that the adequacy of the model for DI spotted stars data is weak. A description of stellar motions and description of data and model used is given in the introduction.

Keywords: Stellar spots, Stellar Evolution, Sunspots, Differential Rotation, Kepler’s Stars, Doppler Imaging stars

Role of Metal Ions, Surfactants and Solvents on Enzymatic Activity of Partial Purified Glucoamylase from Aspergillus niger ER05 - Pages 141-146
Erum Hanif, Shah Ali Ul Qader and Raheela Rahmat Zohra

https://doi.org/10.6000/1927-5129.2018.14.21

Published: 13 April 2018

Abstract: The glucoamylase requirement of different industries should vary in their physiochemical and functional properties, so the investigation of new sources for the novel enzymes is the only solution. The current study describe the production of glucoamylase from Aspergillus niger ER05 in a submerged fermentation. The enzyme then partially purified and then effect of thirteen different metal ions (Cs⁺, K⁺, Na⁺, Ba²⁺, Ca²⁺ Co²⁺, Cu²⁺ , Hg²⁺, Mg²⁺, Mn²⁺, Ni²⁺, Zn²⁺ , Fe³⁺), surfactant as well as organic solvent on catalytic performance of glucoamylase was studied. A newly isolated Aspergillus niger ER05 is hyper producing strain of glucoamylase. Specific activity for the crude enzyme was found to be 6.87 KU/mg. The crude enzyme was partially purified via fractional ammonium sulphate precipitation. Ammonium sulphate saturation from 40-80% was found suitable to precipitate the enzyme. After dialyzing precipitates, the specific activities were found to be 66.33KU/mg with percent yield of 26.5. The inhibitory influence of all metal studies was interestingly found on glucoamylase activity. The strong inhibition was demonstrated in presence of Hg²⁺, Ni²⁺, Zn²⁺, Cu²⁺, Fe³⁺. Only Na⁺ ions were able to maintain the 101% relative activity at 1mM concentration. The SDS completely inhibits the enzyme activity and in presence of tween-80 and triton X-100 glucoamylase exhibited less than 45% relative activity. Furthermore, formaldehyde, isopropanol, ethanol, methanol, and DMSO stabilized the enzyme activity while chloroform inhibits enzyme activity by 48%.

Keywords: Activators, inhibitors, metal ions, surfactants, organic solvents, glucose, Aspergillus niger.