bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of surfactants on antibacterial drugs – A brief review
Authors: Mohd Hamzah Mohd Amir Asyraf , Aruldass Claira Arul , Ahmad Wan Azlina , Setu Siti Aminah 
Published: October 2017

More than half of the reported new discovered/invented drugs are ones with poor solubility, absorption or both. These are the crucial issues that can affect the bioavailability of the drugs. Therefore, improving solubility of poor-soluble drugs is absolutely important. One of the methods to solubilize them in biological fluids is using surfactants. Surfactants are an amphiphilic organic compound containing hydrophilic and lipophilic parts that allow it to reduce the surface tension between two opposite polar phases. Several popular methods used to determine critical micelle concentration which includes surface tension, conductivity and UV-vis spectroscopy. These surfactants plays number of roles in antibacterial compound synthesis include size reduction agent, stabilizer, solubilizer and drug-carrier. This review will also critically discuss on the roles of surfactants in antibacterial compound synthesis/production and its effect on the antibacterial activity of the drugs.
On the dominating number, independent number and the regularity of the relative co-prime graph of a group
Authors: Abd Rhani Norarida , Mohd Ali Nor Muhainiah , Sarmin Nor Haniza , Erfanian Ahmad 
Published: October 2017

Let H be a subgroup of a finite group G. The co-prime graph of a group is defined as a graph whose vertices are elements of G and two distinct vertices are adjacent if and only if the greatest common divisor of order of x and y is equal to one. This concept has been extended to the relative co-prime graph of a group with respect to a subgroup H, which is defined as a graph whose vertices are elements of G and two distinct vertices x and y are joined by an edge if and only if their orders are co-prime and any of x or y is in H. Some properties of graph such as the dominating number, degree of a dominating set of order one and independent number are obtained. Lastly, the regularity of the relative co-prime graph of a group is found.
Pyrolysis of torrefied oil palm wastes for better biochar
Authors: Aliyu Aminu Safana , Abdullahi Nurhayati , Sulaiman Fauziah 
Published: October 2017

The objective of this research work is to investigate the effect of torrefaction on the pyrolysis product. Biomass materials such as empty fruit bunch (EFB), mesocarp fibre (MF) and palm shell (PKS) were torrefied and pyrolyzed. The experiment conditions were set to be respectively at 220 o C of temperature, 10 o C/min of heating rate and 30 minutes holding time for torrefaction and at 650 oC of temperature, 20 o C/min heating rate and 2 hours holding time for pyrolysis. Nitrogen flow rate of 2L/min was maintained for both experiments. The torrefied biomass contains high carbon content and low oxygen content than the raw biomass. Also, the biochar derived from torrefied biomass have high fixed carbon content than the biochar derived from untorrefied biomass. The maximum higher heating value (HHV) of about 31.2 MJkg-1 is obtained in the biochar derived from the torrefied shell. Though, all the biomass materials used in this research have exhibited a positive outcome after being torrefied and pyrolyzed. It is clear from scanning electron microscopy (SEM) images that the biochar (b) and (d) derived from torrefied biomass could be better in the application of soil amendment and water retention due to a large number of uniform holes. Therefore, it can be concluded that pyrolysis of torrefied biomass improved the quality of biochar than the biochar obtained from untorrefied biomass.
Direct synthesis of ZSM-5 from kaolin and the influence of organic template
Authors: Prasetyoko Didik , Rustam Rustam , Ediati Ratna , Septiyana Berty , Zein Yusuf Muhammad , Bahruji Hasliza , Qoniah Imroatul , Hartati Hartati , Nur Hadi 
Published: October 2017

We investigated the transformation of kaolin to ZSM-5 using hydrothermal synthesis method and the influence of organic template as a structure-directing agent. The formation of ZSM-5 from kaolin occurred via dissolution of kaolin to form amorphous silica. Zeolite-like analcime produced when the hydrothermal treatment was extended to 18 h. We found synergistic effect of using a mixture of TPAOH and TPABr organic template to enhance kaolin dissolution, initiate ZSM-5 formation and inhibit the transformation of ZSM-5 to analcime.
Microstructure and superconducting properties of Ag-substituted YBa2-xAgxCu3O7- δ ceramics prepared by sol-gel method
Authors: Ramli Fariesha Farha , Abd Wahab Norazidah , Hashim Azhan 
Published: October 2017

Superconductor YBa2-xAgxCu3O7- δ in a bulk form has been developed through modified sol-gel processing. The preparation involved dissolving metal organic precursor in a mixture of propanoic acid and propylamine which then undergo for annealing at 900 °C for 5 hours and sintering at 950 °C for 5 hours. The bulk samples were characterized using X-ray diffractogram (XRD), resistivity measurement technique and Scanning Electron Microscope (SEM). The highest TC value was found at 84 K for x=0.05. The value decrease as the Ag concentration increase. The highest JC value measured for x =0.05 were 5.977 A/cm2 at 50 K and 4.748 A/cm2 a 60 K. 123 phase remains as orthorhombic for all samples. SEM micrograph showed the clear grains for the pure samples and it became not visible as the Ag concentration increase.
The independence polynomial of n-th central graph of dihedral groups
Authors: Najmuddin Nabilah , Sarmin Nor Haniza , Erfanian Ahmad , Rahmat Hamisan 
Published: October 2017

An independent set of a graph is a set of pairwise non-adjacent vertices while the independence number is the maximum cardinality of an independent set in the graph. The independence polynomial of a graph is defined as a polynomial in which the coefficient is the number of the independent set in the graph. Meanwhile, a graph of a group G is called n-th central if the vertices are elements of G and two distinct vertices are adjacent if they are elements in the n-th term of the upper central series of G. In this research, the independence polynomial of the n-th central graph is found for some dihedral groups.
Brucea javanica seeds as source of potential natural antioxidants to improve biodiesel thermal and oxidative stability
Authors: Hasni Khalil Ullah , Zulkiflee Lubes Zul Ilham , Mohamad Jamaludin , Varman Mahendra 
Published: October 2017

Biodiesel is one of the most promising renewable energy derived from biological sources. Biodiesel is clean and renewable biofuel but its oxidative stability is low. To increase oxidative stability of biodiesel, natural antioxidants are considered as potential compounds to be used. The purpose of the work was to investigate and determine the antioxidation potential of Brucea javanica seeds by applying different antioxidant assays such as 2,2-diphenyl-1-picrylhydrazyl (DPPH), metal chelating and ferric reducing antioxidant power (FRAP). Furthermore, Total phenolic content (TPC) and Total flavonoid content (TFC) tests were done. Among the three extracts of Brucea javanica seeds, ethyl acetate extract showed the highest total phenolic content (98.5 ±0.1mg GAE/g dry extract). The highest total flavonoid content (20 ± 0.4mg QAE/g of dry weight) and DPPH inhibition activity 90%. Ethyl acetate extract also exhibited the highest chelating activity with 59% inhibition in the metal chelating assay. However, the Rancimat showed a maximum of 69hour induction period (IP) in biodiesel when gallic acid is added.
Improved absorbance of holmium activated magnesium-zinc-sulfophosphate glass
Authors: Jupri Siti Aishah , Ghoshal Sib Krishna , Omar Muhammad Firdaus , Sharma Sunita 
Published: October 2017

Constant efforts are dedicated to overcome the limitations of phosphate based glass system, where sulfophosphate glasses (SPGs) played a key role. Rare earth ions (REIs) doped magnesium zinc SPG (MZSPG) systems are technologically prospective due to their several unique attributes. Construction of integrated light ampliﬁer and solid state laser needs the maximum gain within small component dimensions. Thus, Ho3+ ions doped SPGs are believed to meet this demand. Ho3+ ions having sharp optical absorption peaks in the spectral range of 200–900 nm is useful for diversified applications. Conversely, SPGs comprising of oxides of sulphur, phosphorous and at least one other component with SO42- ions contents lower than PO43- with low melting temperature makes them a distinctive class of technologically potential disordered system. In this view, modification of Ho3+ ions absorbance inside SPGs network is challenging. To achieve this goal, following melt-quenching route we prepared a series of Ho3+-doped MZSPG system of composition (60-x)P2O5-(20)ZnSO4-(20)MgO–(x)Ho2O3, where x = 0.0, 0.5, 1.0, 1.5 2.0, and 2.5 mol%. The influence of Ho2O3 concentration on the density, refractive index, and optical absorption properties of the synthesized glass system is examined. The density and refractive index is found to increase with increasing Ho2O3 concentration. The absorption spectra revealed nine prominent peaks centered at 387, 418, 450, 484, 538, 642, 1148 and 1945 nm. The glass absorbance is enhanced with increasing Ho3+ contents. Optical band gap energy is found to range from 3.847 to 3.901 eV. The reduction of Urbach energy from 0.257 to 0.191 eV with increasing Ho3+ contents verified the shrinkage of glass network structure and lowering of defect mediated disorder. In-depth investigations on the structural and optical properties of MZSPG system are underway to achieve the milestones set for photonic devices.
Modified absorption attributes of neodymium doped magnesium-zinc-sulfophosphate glass
Authors: Yusof Nur Nabihah , Ghoshal Sib Krishna , Omar Muhammad Firdaus 
Published: October 2017

Rare-earth doped glass systems with improved absorption and emission features are greatly demanding for diverse applications. In this endavour, selection of right glass host, modifier, rare earth ions with optimized composition is the key issue. This communication reports the conventional melt-quench synthesis of neodymium (Nd3+) doped magnesium-zinc- sulfophosphate glass system of the form (60-x)P2O5-20MgO-20ZnSO4-xNd2O3 (x = 0, 0.5, 1, 1.5, 2.0 and 2.5 mol%). The influence of varying Nd3+ contents on the physical (density, molar volume, molar refractivity, refractive index and electronic polarizability) and absorption properties of the prepared glass system is determined. The amorphousity of the obtained samples is confirmed by XRD analysis. The glass refractive indices (ranged from 1.85 to 1.90) and densites (between 2.63 to 2.77 g.cm-3) are found to increase with increasing concentration of Nd3+ ion. Furthermore, the energies associated with the direct and indirect optical transitions across the forbidden gap are observed to reduce with the increase of Nd3+ ion concentration. Meanwhile, the increase of Urbach energy with increasing Nd3+doping is ascribed to the interaction of rare earth ions with the ligands of the glass network and subsequent transformation of weak bonds into defects. The room temperature UV–Vis-NIR spectra revealed eleven absorption band corresponding to the transitions from the ground state to various excited states of the Nd3+ ion. Incorporation of Nd3+ ion is discerned to enhance the glass absorbance appreciably together with the alteration of physical properties. Present findings may be beneficial for the advancement of Nd3+ ions doped magnesium-zinc-sulfophosphate glass system based photonic devices especially for infrared solid state laser.
First-principles calculations of antimony sulphide Sb2S3
Authors: Radzwan Afiq , Ahmed Rashid , Shaari Amiruddin , Lawal Abdullahi , Xuan Ng Ying 
Published: October 2017

The structural, electronic and optical properties of Sb2S3 have been investigated using full-potential linearized augmented plane wave method within density functional theory (DFT) framework, treating exchange-correlation potential with Engel-Vosko generalized gradient approximation (EV-GGA). Electronic properties calculations were performed with and without taken into account the effects of spin-orbit coupling (SOC) . From our results we found that structural properties,density of states and band structure are in good agreement with experimental results.The effects of SOC and relativistic on electronic properties were found to be negligible. However, optical properties, namely, imaginary and real parts of dielectric function, reflectivity, absorption coefficient, refractive index, extinction coefficient and energy loss function were calculated and analyized.Optical gap of 1.61 eV proves that Sb2S3 metal chalcogenides is a promising material for solar cell device.
Antibacterial finishing of a dyed cotton fabrics using diospyros mespiliformis leaves extracts
Authors: Balarabe Sulaiman , Habibu Shehu , Gumel Sani Muhammad , Ladan Magaji , Birniwa Abdullahi Haruna , Koki Isa Baba , Usman Sharif Nafiu 
Published: October 2017

In this study, leaves of Diospyros mespiliformis was extracted using ethanol and macerated with chloroform and ethyl acetate and later screened for antibacterial properties. The antibacterial analysis was performed qualitatively via disc diffusion method (AATCC 147) against Escherichia coli and Staphylococcus aureus as gram negative and gram positive bacteria respectively. The extract shows a significant activity on the isolated micro-organisms as evidenced by a clear zone of inhibition, more so in the ethyl acetate petri dish indicating its potentials in preventing microbial growth. The extract was then used to dye cotton fabrics by pre-mordanting, simultaneous mordanting and post-mordanting processes. The materials were assessed for fastness properties, such as fastness to washing, light, pressing and rubbing based on AATCC standards. The results show a good to moderate fastness properties suggesting that extract of Diospyros mespiliformis can be successfully used for dyeing of cotton fabric in textile industries thereby reducing the pollution and environmental hazards associated with the use of conventional synthetic chemical dyes.
On the generalized commuting and non-commuting graph for metacyclic 3-groups
Authors: Zamri Siti Norziahidayu Amzee , Sarmin Nor Haniza , El-Sanfaz Mustafa Anis , Rahmat Hamisan 
Published: October 2017

Let be a metacyclic 3-group and let be a non-empty subset of such that . The generalized commuting and non-commuting graphs of a group is denoted by and respectively. The vertex set of the generalized commuting and non-commuting graphs are the non-central elements in the set such that where Two vertices in are joined by an edge if they commute, meanwhile, the vertices in are joined by an edge if they do not commute.
MHD natural convection of ferrofluid from a fixed vertical plate with aligned, transverse magnetic field and convective boundary condition
Authors: Ilias Mohd Rijal , Rawi Noraihan Afiqah , Shafie Sharidan 
Published: October 2017

The present study analyzed the influence of aligned and transverse magnetic field on two dimensional natural convection boundary layer flow of a ferrofluid over a semi-infinte fixed vertical plate in the presence of convective boundary condition. It is assumed that the left surface of the plate is in contact with a hot fluid while the cold fluid on the right surface. Two different base fluids (water and kerosene) containing magnetite (Fe3O4) as ferroparticle are considered. The governing boundary layer equations along with the appropriate boundary conditions are transformed to a set of ordinary differential equations using similarity variables. The resultant system of equations is then solved numerically by using Keller-Box method. Numerical results for the skin friction coefficient and local Nusselt number were presented whilst the velocity and temperature profiles illustrated graphically and analyzed. The effect of the inclined angle, magnetic field parameter, volume fraction, Grashof number and Biot number on the flow field were discussed. It is found that the heat transfer rate at the plate surface with Fe3O4- kerosene ferrofluid is higher than Fe3O4- water.
Gold Nanoparticles Embedded on the Surface of Polyvinyl Alcohol Layer
Authors: Nur Hadi , Md. Nasir Sasha 
Published: October 2017

A novel method for synthesizing polyvinyl alcohol (PVA) embedded gold film is presented. Gold particles, in the size range of 20 to 180 nm, were first prepared by the conventional Turkevitch method by the reduction of gold, hydrogen tetrachloroaurate (HAuCl4) with sodium citrate in water. The resulting gold nanoparticles were characterized by ultra violet-visible (UV-Vis) absorption spectroscopy, dark-field microscopy, transmission electron microscopy (TEM) and field emission electron microscopy (FESEM). In the preparation of PVA embedded gold film, PVA was functionalized with (3-mercaptopropyl) trimethoxysilane (MPTMS) which produced a thiol functionality on the surface. Then, gold particles were embedded on the surface of partially dried functionalized PVA where the gold particles are chemisorbed onto the thiol groups. Their physical properties were studied using Fourier transform infra red spectroscopy (FTIR), FESEM, TEM and UV-Vis diffuse reflectance (UV-Vis DR). Considering that the gold nanoparticles in solution cannot possibly be recovered and reused, the PVA embedded gold film on the other hand, has potential to be reused multiple of times.
Students’ Experience on Their Communicative Learning Teaching in English Speaking Class
Authors: Abas Aslinda , Jaffri Hadijah 
Published: October 2017

This study aims to determine the effectiveness of activities such as oral presentations, role play and group discussions in students’ achievement. The implementation of oral teaching activities have been carried out within the timeframe set by the researchers to study if there is a connection between these activities and the achievement of MUET Speaking among students in Maahad Johor. The combinations of quantitative and qualitative methods were used with the involvement of 70 samples completed a questionnaire for the quantitative data. Through pilot tests conducted, items used in the questionnaire over the validity of the set (> 0.6). The results showed that there was no relationship between oral activities conducted and the achievement in MUET Speaking among students in Maahad Johor with p = 0,962, which is more than the value of α = 0.05. In order to confirm this finding, the researcher then used interview sessions to obtain information in details. Results of interviews with 4 respondents found that they gave a very positive opinion on those oral activities that have been carried out. According to them, they have learnt several Speaking methods, but its effectiveness has not been seen in the achievement of MUET Speaking. Therefore, some recommendations have been listed in improving the achievement of MUET Speaking in the future.
A Questionnaire-based Approach on Technology Acceptance Model for Integrated Multiple Ankle Technology Device on Patient Psychology
Authors: Mohd Latip Hadafi Fitri , Omar A. H. , Jing Tan Mei , Shahrom Ardiyansyah 
Published: October 2017

Sports injury is an issue that frequently occurs among athletes. The most common sports injuries are ankle sprains. Hence, to overcome this problem, the National Sports Institute and the Malaysia Sport School has set up special clinics for athletes undergoing rehabilitation treatment. In RMK 10 (2010-2015), the government aims to provide the best medical facilities and producing high value medical device. In spite of the advancement and variety of available ankle rehabilitation technology device, there is an eminent need to investigate the current position on the acceptance of these rehabilitation devices to assist patient recovery. Therefore, in this study technology acceptance model is designed to investigate the user acceptance on ankle rehabilitation technology device application in healthcare industry. The purpose of this study is to design a quantitative approach based on the technology acceptance model questionnaire as its primary research methodology. It utilized quantitative approach based on Technology Acceptance Model (TAM) to evaluate the system of ankle rehabilitation technology device. The related constructs for evaluation are: Perceived of Usefulness, Perceived Ease of Use, User Satisfaction and Attribute of Usability. All these constructs are modified to suit the context of the study. Moreover, this study outlines the details of each construct and its relevance toward the research issue. The outcome of the study represents series of approaches that will be apply to check the suitability of an ankle rehabilitation technology device on patient in healthcare industry and how well it achieve the aims and objectives of the design.
Supports From Parents, Optimism, and Life Satisfaction in Early Adolescents
Authors: Chong Shue Ling , Baharudin Rozumah 
Published: October 2017

This study examined influences of father and mother support, and optimism on life satisfaction in early adolescents (n = 814; mean age = 13.66 years old) in Malaysia, as well as its variation across gender. Participants were recruited using Probability Proportional to Size (PPS) sampling method from secondary school of four educational zones in Kuala Lumpur. Questionnaires comprising demographic items and measures of the social support, optimism and life satisfaction were self-administered by the students at their respective schools. Data were analyzed using descriptive and inferential statistics including Structural Equation Modeling (SEM) via AMOS. Adolescents who received greater support from their parents reported better life satisfaction. Optimism has an indirect effect on relationship between support from mother and life satisfaction. The model was found as not stable across gender. Support from mother contributed to optimism, and optimism contributed to life satisfaction among adolescent boys, while effect was not found among adolescent girls. Findings imply the importance of considering these variables in prevention and intervention efforts involving early adolescents.
Suicide A Selfish Act Or Selfless Act: Does It Really Matter?
Authors: Sandelararan Annie Margaret , Cheah Phaik Kin , Lee Wan Ying 
Published: October 2017

Globally, over 800,000 people die by suicide every year with one death every forty seconds. There are more deaths from suicide than from war and homicide together (World Health Organization, 2000). Some researchers concluded that suicide is as an act of eternal response to impermanent problems. One perspective is that suicidal behaviour a selfish act. Conversely, other quarters believe that suicidal behaviour is a selfless act. This study aimed to discuss the religious perspectives of suicide from the Christianity, Islam, Hinduism and Buddhism views. As, in the context of religion not all suicides are regarded as selfish acts. This study found that Hinduism accepts a man's right to end his life through the non-violent practice of fasting to death or to save one's honor. Suicide is morally valid if it is practiced one under divine command. Also at the same time, recommendations on suicide prevention in different religious contexts were addressed.