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Kosmos
Astronomia Astrofizyka
Inne

Kultura
Sztuka dawna i współczesna, muzea i kolekcje

Metoda
Metodologia nauk, Matematyka, Filozofia, Miary i wagi, Pomiary

Materia
Substancje, reakcje, energia
Fizyka, chemia i inżynieria materiałowa

Człowiek
Antropologia kulturowa Socjologia Psychologia Zdrowie i medycyna

Wizje
Przewidywania Kosmologia Religie Ideologia Polityka

Ziemia
Geologia, geofizyka, geochemia, środowisko przyrodnicze

Życie
Biologia, biologia molekularna i genetyka

Cyberprzestrzeń
Technologia cyberprzestrzeni, cyberkultura, media i komunikacja

Działalność
Wiadomości | Gospodarka, biznes, zarządzanie, ekonomia

Technologie
Budownictwo, energetyka, transport, wytwarzanie, technologie informacyjne

Asian Journal of Applied Sciences

The biomedical, chemical, drug and food industries have great demand of an
alcohol sensor with high sensitivity and selectivity which can operate at low
temperature. In this study, CuO thin films were deposited on well cleaned glass
substrates by spray pyrolysis technique for 0.1, 0.2 and 0.3 molar concentrations
of copper chloride precursor solutions and at a substrate temperature of 300°C
and at an air pressure of 0.4 kg cm-2. X-ray diffraction patterns
of the prepared films revealed the formation of CuO thin films having monoclinic
structure with a grain size ranging from 35 to 54 nm. The microstrain and dislocation
densities are found to decrease with increase in molar concentration. The surface
morphology and the elemental composition of the deposited samples were analyzed
using SEM and EDAX. The change in resistivity of the films was studied with
respect to the change in temperature using two probe method. From Laser Raman
spectral studies, the characteristic Raman peaks of the prepared samples were
observed. The ethanol gas sensing properties of the prepared films were studied
for 100 and 200 ppm ethanol vapour.

http://scialert.net/abstract/?doi=ajaps.2014.671.684 2014/09/30 - 04:56

A series of sandwiched films in the configuration, Ni(100 nm)/Al(t)/Ni(100
nm); t = 10 nm, 20 nm,……, 100 nm (labeled as NAN1, NAN2,………,
NAN10) were produced by thermal and electron beam gun evaporation techniques.
The films were deposited onto the glass substrates held at 200°C, under
high vacuum conditions in a Hindhivac coating unit. The structure, grain size
and interplanar distances were probed by X-Ray Diffraction (XRD). The grain
sizes obtained were in the order of few nanometers and decreased with increasing,
t. Electrical resistivity in the temperature range from 4 to 300 K has been
measured in an Oxford Instruments make resistivity measurement setup. The resistivity
decreased nonlinearly and continuously with increasing temperature for the films
NAN1, NAN3 and NAN7 similar to that of a semiconductor. Mott’s small polaron
hopping and variable range hopping models due to Mott and Greave have been employed
to understand resistivity variation with temperature. In the remaining films
resistivity decreased up to some temperature and increased thereafter. This
indicated a kind of transition occurring in these films from Metallic to Semiconductor
(MST). These results are significant as neither of the constituent layers in
the present films is semiconducting by nature. The resistivity variation with
temperature of some of these films has been analyzed using semi-classical conductivity
model of Boltzman which incorporates quantum corrections in to it. It is for
the first time that the sandwiched films of the present configuration have been
investigated for structure and low temperature resistivity and data analyzed
thoroughly.

http://scialert.net/abstract/?doi=ajaps.2014.685.695 2014/09/30 - 04:56

The benefits of Organic Field Effect Transistors (OFETs), such as economical,
large area fabrication and flexibility, have recently attracted much attention.
Utilitarian transistors demand low threshold voltage, high mobility, large on/off
ratio and stability. Innovation in organic semiconductors is crucial to obtaining
these specifications. The requirement for high mobility and low operating voltages
is the motivation for using high dielectric constant materials in Organic Field
Effect Transistors (OFETs). In this study the fabrication and performance of
an OFET with silica nanoparticle (dielectric constant of silica~3.9) as dielectric
layer is reported. The device is fabricated with, bottom contact architecture
with Poly (3-hexylthiophene) (P3HT) as active layer and aluminium as electrode.

http://scialert.net/abstract/?doi=ajaps.2014.696.704 2014/09/30 - 04:56

The Laves phases binary intermetallic compound HfTi2 is one of the
potential candidates for the storage of hydrogen. The knowledge on thermal properties
of hydrogenated HfTi2 is important in order to use this material
for hydrogen storage application. This study has reported important thermal
properties such as phonon frequency distribution, defect modes, mean square
displacement and diffusion parameters of H in the hydrogenated HfTi2
using lattice dynamical investigation involving green’s function method
and scattering of phonons by defect space atoms.

http://scialert.net/abstract/?doi=ajaps.2014.705.712 2014/09/30 - 04:56

Lanthanum modified lead zirconate titanate (PZT) thin film with molecular formula
Pb0.92La0.08[Zr0.52Ti0.48]0.98O3
(PLZT) was prepared by spin coating of sol-gel solution on Pt/SiO2/Si
substrate. Effect of different chelating ligands (Formamide, poly ethylene oxide,
ethylene glycol) on phase formation, microstructure and electrical properties
of PLZT thin films were studied to improve the quality of the film for MEMS
application. The XRD patterns of the thin films revealed single phase formation
of PLZT material with varying crystal structures for different chelating ligands.
The Atomic Force Microscopy (AFM) images of these thin films showed surface
profiles of 7.3 nm for formamide, 3.78 nm for Poly Ethylene Oxide (PEO) and
2.11 nm for Ethylene Glycol (EG). The dielectric and ferroelectric properties
of PLZT film prepared with formamide showed higher spontaneous polarization
(Ps) (39.68 μC/cm2), remanent polarization (Pr)
(12.09 μC/cm2), dielectric permittivity (1840) and piezoelectric
coefficient d33 (415 pm/V) compared to the films prepared with PEO
and EG as chelating agents.

http://scialert.net/abstract/?doi=ajaps.2014.713.720 2014/09/30 - 04:56

The transition metal chalcogenide nanostructures of NiSe and CoSe in different
states namely cationic, anionic and neutral are completely simulated and optimized
successfully by B3LYP/LanL2DZ basis set. Stability of transition metal chalcogenide
structures has been conversed by using calculated energy and vibrational studies.
Electronic properties of NiSe and CoSe are studied in terms of HOMO-LUMO gap,
electron affinity and ionization potential. The point symmetry and dipole moment
of NiSe and CoSe are also reported. This study is concentrated in enhancing
electronic properties of transition metal chalcogenide which is most applicable
to solar cells, lithium ion batteries and as catalyst.

http://scialert.net/abstract/?doi=ajaps.2014.721.728 2014/09/30 - 04:56

Manganese containing Diluted Magnetic Semiconductors (DMS) have recently attracted
much attention due to their potential applications in solar selective coatings,
solar cells, sensors, photoconductors etc. Among the available DMSs, Manganese
Sulphide (MnS) is broadly studied because of its magneto-optical properties
and wide band gap nature. In present study, first time, MnS thin films were
deposited onto glass substrates by nebulizer technique using the precursor solutions
of manganese chloride (MnCl2.4H2O) and thiourea (SC(NH)2)2
at a temperature of 350°C. The molar concentrations were varied from
0.25-1.5 M. The structural, optical and morphological studies of deposited films
were carried out using x-ray diffractometer, UV-Vis-NIR spectrophotometer and
scanning electron microscope, respectively. X-ray diffraction results revealed
the crystallinity of MnS films improved with increasing precursor solution concentration.
The absorption edges shift towards lower wavelength region, indicating a systematic
raise in energy band gap with increasing precursor solution concentration up
to 1.0 M which attributed to the lower defect density near the band edge. The
broad emission peak at 420 nm corresponding to the band edge emission was observed
in the PL spectra. The morphological study revealed the polycrystalline nature
of the deposited MnS thin film.

http://scialert.net/abstract/?doi=ajaps.2014.729.736 2014/09/30 - 04:56

High purity Indium oxide pellets were used to prepare In2O3
thin films using e-beam evaporation. Ultrasonically cleaned substrates were
used for the deposition of In2O3 thin films. The thin
films were deposited at a substrate temperature of 673 K under 3x10-5
torr vacuum. The crystallinity of the In2O3 thin films
was investigated using GIXRD. The films were found to be polycrystalline in
nature and crystallizes in a cubic structure with preferred (2 2 2) orientation.
The surface morphology, thickness and compositional analysis were investigated
for these films using Scanning Electron Microscope (SEM) and Energy Dispersive
X-Ray Spectroscopy (EDS). Thickness of the films was found to be 369 nm. Optical
transmission measurements were carried out on In2O3 thin
films using UV-VIS spectrophotometer in the wavelength range 300-1000 nm and
it was confirmed that these thin films exhibits good transparency with an average
transparency (90%) in visible region. The optical band gap was estimated from
the optical transmittance data. The optical constants like optical band gap
and other parameters were calculated from the optical absorption data. These
films were found to be promising materials for TCO applications.

http://scialert.net/abstract/?doi=ajaps.2014.737.744 2014/09/30 - 04:56

Ion Beam Sputtering (IBS) technique has been used to prepare a series of hydroxyapatite
(HA) thin films on Ti and Ti alloy substrates for biomedical application. We
report the effect of Post Deposition Heat Treatment (PDHT) on the structural,
compositional and surface characteristics of HA films deposited on Ti-6Al-4V.
The films underwent PDHT for 2 h at 300, 400, 500 and 600°C under air environment.
After PDHT, the structure and the chemical composition of the films were characterized
using Rutherford Backscattering Spectrometry (RBS), X-ray Diffraction (XRD),
Fourier transform infrared absorption spectrometry (FTIR) and Scanning Electron
Microscopy (SEM). The results showed that the crystallinity of HA increased
with temperature. However, SEM results revealed that some cracks were observed
if the temperature of PDHT was higher than 600°C. FTIR measurements showed
that the existence of hydroxyl and phosphate bands in all films increased with
temperature. RBS analysis indicated that the as-deposited films had a low Ca/P
ratio which increased to stoichiometric value with increasing PDHT temperature.
From this study we suggest that 600°C is probably the best PDHT temperature
to obtain a better characterization and surface properties of HA film produced
by IBS. It can also be concluded that IBS can be used as an alternative method
for deposit HA film on titanium alloy substrate.

http://scialert.net/abstract/?doi=ajaps.2014.745.752 2014/09/30 - 04:56

Vanadium pentoxide (V2O5) solution was synthesized by
melt quenching method. Ultrasonically and chemically cleaned quartz substrates
were dip coated with V2O5 solution by withdrawal speed
of 2 cm min-1 and the films dry at Room Temperature (RT). The prepared
films were subjected for annealing at different temperatures 473, 573 and 673
K for 1 h. The crystallinity of the V2O5 films was examined
by X-ray Diffraction (XRD). XRD pattern of the V2O5 thin
films confirmed the polycrystallinity of the film with orthorhombic structure
with preferred orientation along (0 0 1) direction. Optical and electrical characteristics
of the V2O5 thin films were studied by optical double
beam UV-Visible spectrophotometry and two probe techniques. The optical results
show that the optical optical bandgap (Eg) was found to decrease
with increasing annealing temperature. The dependence of the crystallite size,
optical bandgap (Eg) and activation energy (Ea) has been
reported for V2O5 thin films.

http://scialert.net/abstract/?doi=ajaps.2014.753.760 2014/09/30 - 04:56

Ti-C-N hard coatings were deposited on high speed steel substrates using reactive
magnetron sputtering. Surface morphology and cross section micrographs have
shown dense columnar microstructure. Compressive stresses were created in the
coatings by increasing substrate bias during the deposition at various thicknesses
of coatings. Decrease in compressive stress with depth was observed in depth
dependent stress study using grazing incidence X-ray diffraction study. Pole
figure analysis of the coatings confirmed the strong (111) fibre texture. Mechanical
properties of coatings are evaluated using nano indentation. Average hardness
and modulus values obtained are 34 GPa and 310 GPa, respectively. Post-mortem
analysis of Vickers indented zone shows revealed concentric square cracks.

http://scialert.net/abstract/?doi=ajaps.2014.761.767 2014/09/30 - 04:56

The ternary compounds cadmium lead telluride have been prepared by oxalic acid
method. Thin films were coated on glass substrates by vacuum evaporation method
(Hindhivac 12A4). The structural properties of the material have been studied
using X-ray diffraction technique. The result shows that material is crystalline
in nature and the peaks in the XRD graph of CdPbTe corresponds to cubic structure.
The lattice parameter and grain size have been calculated. The surface morphology
of the thin film is studied using Scanning Electron Microscope (SEM). The SEM
analysis shows that surface of the film is uniform and crystalline in nature.
Thicknesses of the films have been determined by gravimetric method. The optical
absorbance and transmittance have been studied by using UV spectrophotometer
in the range of wavelength 300-1100 nm. The optical band gap of this material
is found to be 1.24 ev.

http://scialert.net/abstract/?doi=ajaps.2014.768.773 2014/09/30 - 04:56

The different structures of PbO such as hexagonal sheet, tubular, bucky ball
and cone super cells were constructed and optimized using density functional
theory. The total energy of PbO super cells were calculated and it is inferred
that the stability of the super cells depends on the number of atoms, more number
of atoms increases the stability of the super cell. The bonding capability depends
on the electronic charge of the molecule. The molecular electronic configurations
were analyzed using Mulliken population analysis. The electronic properties
of PbO super cells were discussed in terms of density of states. The reported
results will provide the information about the realistic structures of PbO super
cells which helps in the synthesis of new nanomaterial.

http://scialert.net/abstract/?doi=ajaps.2014.774.779 2014/09/30 - 04:56

MgO thin film was deposited on a siliconglass substrate using home built spray
pyrolysis method at 230°C. Aqueous solution of 50 mL containing magnesium
chloride hexahydrate was sprayed as a fine mist at a pressure of 2 kg cm-2
with a flow rate of 3 mL min-1 on a preheated glass substrate. The
optical property, structural property and surface morphology of the film was
analyzed without any post annealing and those properties were studied by photoluminescence
spectroscopy, X-ray diffraction (XRD), UV-VIS spectrophotometer, Field Emission
Scanning Electron Microscopy (FESEM) and the obtained results were discussed.

http://scialert.net/abstract/?doi=ajaps.2014.780.785 2014/09/30 - 04:56

Nano crystalline zinc oxide (ZnO) films were fabricated by dip coating of ZnO
hydrogel. Zinc nitrate hexahydrate and sodium carboxymethyl cellulose were used
to prepare the hydrogel. The dip coated samples were annealed at 400°C to
obtain the high quality thin films. The films were characterized by X-Ray Diffraction
(XRD) which indicated that the films are single phase with the wurtzite structure.
Surface morphology of the nanoparticles were studied by Field Emission Secondary
Electron Microscopy (FESEM) and optical properties were studied by photo luminescence
spectroscopy. Further, gas sensing behaviour were checked for the coated films
for ammonia and acetaldehyde vapours at room temperature.

http://scialert.net/abstract/?doi=ajaps.2014.786.791 2014/09/30 - 04:56

The detection of pathogenic organisms is an important aspect of the routine
monitoring of contaminants in food. In this study, we developed a new concept
of measuring bacterial concentration present in food samples using Magnetic
Nanoparticles with congo red dye. Magnetic Nanoparticles (MNPs) were synthesized
by Chemical co-precipitation method which is often preferred for production
of MNPs as it’s the best method to improve homogeneity compared to physical
or biological synthesis methods. Chitosan from amine group when coated with
chemically synthesized MNPs was used to rapidly capture bacteria due to the
binding of protein-receptor interactions. Finally, the surface modified chitosan-magnetite
nanocomposite particles were recovered from the reaction mixture by using an
external permanent magnet. Thus the obtained surface modified MNP’s with
pathogens were isolated and incubated at 37°C for few minutes and then,
conjugated with 10 μL of Red light emitting dye/marker which emit light
upon supply of input light source to detect fluorescence and measure the OD
(optical density). The assay was measured at absorbance wavelength of 498 nm
using fluorescence spectroscopy (Perkin Elmer). Optical Density (OD) or the
intensity output gives the measure of bacterial concentration in food. This
method of food borne pathogen detection provides a high throughput for the analysis
of pathogenic microbes in food samples and also could detect bacterial concentration
in few minutes when compared to existing conventional and immunological method
of detection.

http://scialert.net/abstract/?doi=ajaps.2014.792.797 2014/09/30 - 04:56

A new approach has been proposed to synthesis pure ZnO nanoparticles from zinc
nitrate hexa-hydrate precursor and sodium carboxymethyl cellulose capping agent.
The resulting nanoparticles were characterized by X-ray Diffraction (XRD), Fourier
Transform Infra-red (FTIR) spectroscopy, photoluminescence spectroscopy and
Field Emission Scanning Electron Microscopy (FESEM). The XRD results showed
that particle size is in the range of few nanometers with hexagonal wurtzite
structure. Photoluminescence and FESEM results suggested that the adopted method
can be successfully utilized for the preparation of size controlled nanocrystalline
ZnO powder.

http://scialert.net/abstract/?doi=ajaps.2014.798.803 2014/09/30 - 04:56

Niobium nitride (NbN) thin films deposited by DC reactive magnetron sputtering
on oxidized silicon and glass substrates at room temperature were found to be
superconducting in the range of ~11.4-12.3 K depending on the sputtering conditions.
All the NbN thin films showed a negative temperature co-efficient of resistance
above 25 K indicating the presence of disorder. The superconducting transition
temperature (Tc), onset temperature (To) at which temperature
dependence of resistance becomes positive and width of the superconducting transition
(ΔTc) did not show direct correlation to the resistivity measured
at 300 K. The optical properties of the films were measured using a rotating
polarizer type spectroscopic ellipsometer in the energy range of 1.5-5 eV under
ambient conditions. Assuming the low frequency dependence of real part of the
dielectric function is indicative of a metallic behavior, we have found that
this metallicity is not correlated to all the three superconducting properties
measured.

http://scialert.net/abstract/?doi=ajaps.2014.804.808 2014/09/30 - 04:56

The fabrication of thin film based capacitors with different metal electrodes
(Al, Cu) and their application towards void fraction measurement is carried
out in this study. Void fraction is a measure of empty spaces in any medium.
The void fraction is measured as capacitance in the capillary tube and processed
through embedded system. The thin film capacitor is designed on a capillary
tube through thermal evaporation technique with the above given metal elements.
Capillary tube with different diameters ranging from 5-10 mm and length of 7
inch were used and deposited with metal elements mentioned above with a small
distance between them. The capillary tube is used as insulator with metal elements
deposited above them as metal electrodes. Changes in capacitance value due to
the voids were measured through LCR/Z meter. Before coating the electrodes on
the capillary tubes, the films were characterized for their structural, morphological
and electrical properties to obtain capacitors with desired value of capacitance.

http://scialert.net/abstract/?doi=ajaps.2014.809.813 2014/09/30 - 04:56

Magnonic crystals are periodic composites of magnetic materials for propagating
spin waves. The periodic modulation in magnonic crystal plays a vital role in
the formation of bandgaps at the Brillouin Zone (BZ) boundaries leading towards
possible applications in spin wave filters. In this study, we explore the possibility
of tailoring the magnonic bandgap in one-dimensional (1D) square antidot waveguide
structures by micromagnetic simulation. The space-time variations of magnetization
in these structures are obtained by solving the Landau-Lifshitz-Gilbert (LLG)
equation using OOMMF by applying spatially and temporally varying “sinc”
function normal to the waveguide plane in presence of a bias field of strength
1.01 and 0.505 T along the length of the waveguide. The dispersion relations
are obtained by 2D discrete Fourier transform of the space-time data. We have
investigated how the bias field affects the magnonic band structures and the
corresponding bandgaps for four different materials. From the results we clearly
observe a downward shifting of bandgaps towards lower frequency when the biasing
field is decreased while the width of the bandgap remains same. Hence, it provides
a simplest way for designing spin wave filters of different frequency regimes.

http://scialert.net/abstract/?doi=ajaps.2014.814.818 2014/09/30 - 04:56

To solve the problem of drag force calculation between pick-ups mechanics of
Beach Cleaner and sand, based on Finite Volume Method (FVM) in FLUENT, a model
was built and converted the pick-ups sand shear motion into sand pick-ups erosion
motion. By introducing Standard K-ε turbulence model and SIMPLE algorithm
with pressure-correction,the force of pick-ups in different sand depth conditions
was analyzed. By adopting Least-Squares Method in MATLAB, the simulation and
experimental curves of pick-up force were fitted respectively and reached the
function expressions, connecting the pick-up forces with sand depth. The results
indicate: The relative errors of impact force values of sand from the FLUENT
simulation and experimental values from field test decrease to ±4.5%
and the fitting lines of simulation and experiment agree closely and prove that
the simulation models and methods are feasible to compute the drag force.

http://scialert.net/abstract/?doi=ajaps.2014.652.661 2014/09/24 - 18:10

In this study, we compare three meta-heuristics approaches: hill-climbing,
simulated annealing and late acceptance hill-climbing algorithm, for solving
traveling salesman problem. All algorithms were tested on seven traveling salesman
problem instances listed in LIBTSP datasets. Each algorithm was implemented
and evaluated independently using its parameter. Performance were compared between
all algorithms and evaluated in terms of objective function that calculated
to find the optimal rout within several selected routes. The main conclusion
is that late acceptance hill-climbing algorithm performs better than simulated
annealing and simple hill-climbing as far as solution quality is concerned whilst
simple hill-climbing gives the worst performance according to its poorness in
global search.

http://scialert.net/abstract/?doi=ajaps.2014.662.670 2014/09/24 - 18:10

The cooperation of Relay-Based Cellular Network (RBCN) and Orthogonal Frequency-Division Multiple Access (OFDMA) techniques provide rich of promising solutions especially in terms of Radio Resource Management (RRM). However, the main challenge of this cooperation is managing the resources in a dynamic system in the midst of co-channel interference. Allocating of the RRM associated schemes have been developed to overcome these interferences and to operate the relays in a dynamic and opportunistic manner. The deployments of these RRM schemes have enormous matrices of combination analyzing these performances are of vital essence. There are different simulator tools to address these needs such as NS2, OPNet, OMNet++, etc. An effort to enrich these repositories of simulators is to provide a discrete customization of analyzing the main aim of the study. A discrete event simulation for RBCN evaluation using a general-purpose programming language has been solved. The performance analysis orientation is on Signal-to Interference-plus-Noise Ratio (SINR) algorithm with specific focus on the transmission reliability of relays for channel fading in terms of spectral efficiency for downlink of OFDMA relay-based cellular networks. The developed simulator has been extensively tested and has proven to be a valid and substantial simulator.

http://scialert.net/abstract/?doi=ajaps.2014.589.606 2014/09/17 - 03:36

The Zn1-xCdxS (0≤×≤1) thin films have been prepared using a low cost and simple spray pyrolysis technique onto preheated glass substrates at temperature 523 K. The surface morphology, structural, optical and electrical properties of the as-deposited and annealed Zn0.20Cd0.80S films were studied by optical microscopy, Energy Dispersive X-ray (EDX), X-Ray Diffraction (XRD), UV-visible spectroscopy and Vander Pauw method, respectively. The films are shown inhomogeneous surfaces, less defined grain boundaries. The elemental analysis (EDX) revealed that the deposited films are of Zn, Cd and S compositions. X-ray diffraction patterns indicated that the as-deposited films are amorphous in nature and the annealed film is found to be crystalline structure. The average grain size of the annealed film is found to be 8-47 nm and its value increases with the increase of annealing temperature. Various optical constants viz., optical band gap, extinction coefficient, refractive index and dielectric constant have been studied. The direct optical band gap energy of the as-deposited and annealed films is varied from 3.64-2.40 eV and 2.62-2.1 eV, respectively. The dc electrical conductivity increases with the increase of temperature and also with Cd doping.

http://scialert.net/abstract/?doi=ajaps.2014.607.620 2014/09/17 - 03:36

Cell Free Supernatants (CFS) containing bacteriocin of Enterococcus faecium NM2 (E. faecium NM2) isolated from urine inhibited many gram-positive and gram-negative pathogenic bacteria. It also inhibited the Candida albicans M2 fungus. The antibiotic sensitivity test of the indicator bacteria showed that these strains were resistant to 60-75% of the antibiotics used. The E. faecium NM2 bacteriocin was purified by ammonium sulphate precipitation and gel filtration and a 3600 fold-increase in specific activity of bacteriocin was obtained. The purified bacteriocin showed an apparent molecular mass of Ca, 5 KDa. Amino acid analysis showed that the E. faecium NM2 bacteriocin consists of 16 amino acids with high content of glycine, alanine, glutamic acid and asparagine. The E. faecium NM2 bacteriocin was designated enterocin NM2 and showed a bactericidal action on sensitive bacterial strains used. Enterocin NM2 could be classified as a novel variant within class IIc bacteriocins.

http://scialert.net/abstract/?doi=ajaps.2014.621.634 2014/09/17 - 03:36

Chitra river is an important water body in Southwestern Bangladesh in terms
of fish production. Fisheries resources in this river are on the decline due
to over exploitation, manmade pollution and inadequate management of inland
waters. The present study was conducted to explore the diversity and to check
the conservation status of fish fauna in the Chitra river. Fish samples were
collected fortnightly from seven sampling stations of the Chitra River at Jessore
district in Southwestern Bangladesh during August 2011 to July 2012. A total
of 53 species of fish under 10 orders and 23 families were recorded. Cypriniformes
were most leading order constituting 33.96% of the total fish population followed
by Siluriformes (22.64%), Perciformes (24.53%), Clupeiformes (1.89%), Synbranchiformes
(5.66%), Osteoglossiformes (1.89%), Beloniformes (1.89%), Mugiliformes (3.77%),
Anguiliformes (1.89%) and Tetraodontiformes (1.89%). Fishes in this river is
seriously affected by the various kinds of human development interventions and
activities, especially in the areas of agriculture, forestry, fisheries, urbanization,
industries, chemicals, minerals, transport and tourism. Estimates from these
indices were indication of low fish species composition and richness and unevenness
in the population of fish in river Chitra. For sustainability of fishery resources,
an adequate knowledge of species composition, diversity and relative abundance
of water bodies must be understood and vigorously pursued. Therefore, there
is a need for the conservation and sustainable management of the fisheries resources
of Chitra water body by relevant agencies.

http://scialert.net/abstract/?doi=ajaps.2014.635.643 2014/09/17 - 03:36

This study examines the issues of the organized crime social consequences assessment and its impact on the shadow economy of Kazakhstan. The study is based on the results of studies of a number of scientists who had used an economic approach to the organize crime and considere it as an institution of the criminal enterprise. However, the Kazakhstan evaluation system of the shadow economy size does not consider the impact of the criminal factors in general and organized crime in particular. At the same time, such American scientists as Levitt and Venkatesh, who had conducted a detailed financial analysis of a separate drug gang, have proposed a possible algorithm of such calculation in 1998. Based on their scheme, the authors propose a set of measures for evaluating the real impact of organized crime on the shadow economy of Kazakhstan.

http://scialert.net/abstract/?doi=ajaps.2014.644.651 2014/09/17 - 03:36

The cooperation of Relay-Based Cellular Network (RBCN) and Orthogonal Frequency-Division Multiple Access (OFDMA) techniques provide rich of promising solutions especially in terms of Radio Resource Management (RRM). However, the main challenge of this cooperation is managing the resources in a dynamic system in the midst of co-channel interference. Allocating of the RRM associated schemes have been developed to overcome these interferences and to operate the relays in a dynamic and opportunistic manner. The deployments of these RRM schemes have enormous matrices of combination analyzing these performances are of vital essence. There are different simulator tools to address these needs such as NS2, OPNet, OMNet++, etc. An effort to enrich these repositories of simulators is to provide a discrete customization of analyzing the main aim of the study. A discrete event simulation for RBCN evaluation using a general-purpose programming language has been solved. The performance analysis orientation is on Signal-to Interference-plus-Noise Ratio (SINR) algorithm with specific focus on the transmission reliability of relays for channel fading in terms of spectral efficiency for downlink of OFDMA relay-based cellular networks. The developed simulator has been extensively tested and has proven to be a valid and substantial simulator.

http://scialert.net/abstract/?doi=ajaps.2014.589.606 2014/09/17 - 03:35

The Zn1-xCdxS (0≤×≤1) thin films have been prepared using a low cost and simple spray pyrolysis technique onto preheated glass substrates at temperature 523 K. The surface morphology, structural, optical and electrical properties of the as-deposited and annealed Zn0.20Cd0.80S films were studied by optical microscopy, Energy Dispersive X-ray (EDX), X-Ray Diffraction (XRD), UV-visible spectroscopy and Vander Pauw method, respectively. The films are shown inhomogeneous surfaces, less defined grain boundaries. The elemental analysis (EDX) revealed that the deposited films are of Zn, Cd and S compositions. X-ray diffraction patterns indicated that the as-deposited films are amorphous in nature and the annealed film is found to be crystalline structure. The average grain size of the annealed film is found to be 8-47 nm and its value increases with the increase of annealing temperature. Various optical constants viz., optical band gap, extinction coefficient, refractive index and dielectric constant have been studied. The direct optical band gap energy of the as-deposited and annealed films is varied from 3.64-2.40 eV and 2.62-2.1 eV, respectively. The dc electrical conductivity increases with the increase of temperature and also with Cd doping.

http://scialert.net/abstract/?doi=ajaps.2014.607.620 2014/09/17 - 03:35

Cell Free Supernatants (CFS) containing bacteriocin of Enterococcus faecium NM2 (E. faecium NM2) isolated from urine inhibited many gram-positive and gram-negative pathogenic bacteria. It also inhibited the Candida albicans M2 fungus. The antibiotic sensitivity test of the indicator bacteria showed that these strains were resistant to 60-75% of the antibiotics used. The E. faecium NM2 bacteriocin was purified by ammonium sulphate precipitation and gel filtration and a 3600 fold-increase in specific activity of bacteriocin was obtained. The purified bacteriocin showed an apparent molecular mass of Ca, 5 KDa. Amino acid analysis showed that the E. faecium NM2 bacteriocin consists of 16 amino acids with high content of glycine, alanine, glutamic acid and asparagine. The E. faecium NM2 bacteriocin was designated enterocin NM2 and showed a bactericidal action on sensitive bacterial strains used. Enterocin NM2 could be classified as a novel variant within class IIc bacteriocins.

http://scialert.net/abstract/?doi=ajaps.2014.621.634 2014/09/17 - 03:35

Chitra river is an important water body in Southwestern Bangladesh in terms
of fish production. Fisheries resources in this river are on the decline due
to over exploitation, manmade pollution and inadequate management of inland
waters. The present study was conducted to explore the diversity and to check
the conservation status of fish fauna in the Chitra river. Fish samples were
collected fortnightly from seven sampling stations of the Chitra River at Jessore
district in Southwestern Bangladesh during August 2011 to July 2012. A total
of 53 species of fish under 10 orders and 23 families were recorded. Cypriniformes
were most leading order constituting 33.96% of the total fish population followed
by Siluriformes (22.64%), Perciformes (24.53%), Clupeiformes (1.89%), Synbranchiformes
(5.66%), Osteoglossiformes (1.89%), Beloniformes (1.89%), Mugiliformes (3.77%),
Anguiliformes (1.89%) and Tetraodontiformes (1.89%). Fishes in this river is
seriously affected by the various kinds of human development interventions and
activities, especially in the areas of agriculture, forestry, fisheries, urbanization,
industries, chemicals, minerals, transport and tourism. Estimates from these
indices were indication of low fish species composition and richness and unevenness
in the population of fish in river Chitra. For sustainability of fishery resources,
an adequate knowledge of species composition, diversity and relative abundance
of water bodies must be understood and vigorously pursued. Therefore, there
is a need for the conservation and sustainable management of the fisheries resources
of Chitra water body by relevant agencies.

http://scialert.net/abstract/?doi=ajaps.2014.635.643 2014/09/17 - 03:35

This study examines the issues of the organized crime social consequences assessment and its impact on the shadow economy of Kazakhstan. The study is based on the results of studies of a number of scientists who had used an economic approach to the organize crime and considere it as an institution of the criminal enterprise. However, the Kazakhstan evaluation system of the shadow economy size does not consider the impact of the criminal factors in general and organized crime in particular. At the same time, such American scientists as Levitt and Venkatesh, who had conducted a detailed financial analysis of a separate drug gang, have proposed a possible algorithm of such calculation in 1998. Based on their scheme, the authors propose a set of measures for evaluating the real impact of organized crime on the shadow economy of Kazakhstan.

http://scialert.net/abstract/?doi=ajaps.2014.644.651 2014/09/17 - 03:35

Monitoring of contaminated water and soil in waste disposal sites is normally
carried out by chemical analysis of surface water, leachate and soils as well
as by geophysical measurements. Leachate is defined as any contaminated liquid
or wastewater generated from rain water percolating through solid waste materials,
accumulating contaminants and moving into subsurface and surrounding areas.
A study was carried out to detect the leachate movement at Sungai Sedu landfill
located on ten square acres near Banting town. Geologically, the study area
is underlined by Holocene marine clay of Gula and Beruas Formations sitting
on top of metasedimentary rocks of Kenny Hill formation. Geophysical surveys
using techniques 2D electrical resistivity imaging, Vertical Resistivity Profiling
(VRP) as well as geochemical analysis on soil and water samples were used in
this study to investigate the level of leachate migration from the dumping spot
into the surrounding areas. This was based on characterizing the measured electrical
resistivities and analyzing the heavy metal concentrations. The 2D electrical
imaging surveys were carried out on 8 profiles while the VRP surveys were conducted
in 6 boreholes. Based on resistivity imaging sections, the leachate was detected
to migrate at about 3-5 m depth. Basically the resistivity of leachate is less
than 1 Ωm. The concentrations of heavy metals also showed that the leachate
has migrated into the nearby river. The concentrations of heavy metals in river
bank soil, leachate and surface water samples are high and exceeded the background
values especially Ni, Mn, Zn, Cr and As. Conductivity of the river bank soil,
leachate, surface water and the surrounding soil samples were approximately
around 6600 and 20000-50000 μS cm-1, respectively with pH values
of 3-5. The high concentrations of heavy metals and soil conductivities indicate
the possibility of leachate migration from the dumping site to contaminate the
nearby river, soil and groundwater of the study area.

http://scialert.net/abstract/?doi=ajaps.2014.518.535 2014/07/07 - 11:12

In the recent past, the applications of artificial intelligence in data analysis and prediction has indisputably increased. Fuzzy Logic (FL) and Artificial Neural Networks (ANN) find extensive applicability with the aim of achieving human-like or superior performance. FL is used in the fields of consumer products, industrial process control, medical instrumentation and portfolio selection while ANN applications include system identification and control, decision making, patter recognition, sequence recognition, visualization, data mining and financial applications. FL and ANN have the ability to learn from its environment and to improve its performance through learning. This study presents application of FL and ANN in predicting the 28 day compressive strength of self-compacting concrete containing mineral and chemical admixtures. This becomes extremely advantageous in predicting the compressive strength of Self Compacting Concrete (SCC) mixes containing binary, ternary or quaternary blends. The results obtained from the fuzzy logic prediction model and from ANN training, testing and validation were compared with the experimental values from the literature and its performance was evaluated in terms of root mean square error, correlation coefficient, coefficient of performance, mean absolute error and percentage mean relative error.

http://scialert.net/abstract/?doi=ajaps.2014.536.551 2014/07/07 - 11:12

Street production is a major contributor of heavy metals to the environment. Soil samples were collected from seven sampling stations around Udu River in the vicinity of a steel plant and two sampling stations as control from around Ovwuvwe stream for two years (two dry and two rainy seasons). Heavy metals were determined by flame atomic absorption spectroscopy after digestion with 2M HNO3 and physicochemical parameters determined by various standard methods. Important results are pH (5.85±0.32), Fe (3110±1500 mg kg-1), Pb (126±40 mg kg-1), Cd (9.2±6.4 mg kg-1), Zn (112±41 mg kg-1), Ni (44±50 mg kg-1) and Cu (18.3±8.2 mg kg-1). The average concentrations of all the metals with the exception of Cu exceeded different soil guideline values with which they were compared. Most sampling stations are polluted with heavy metals, the contamination factor of the heavy metals exceeded unity in most sampling sites. The Pollution Load Index (PLI) of stations A and C are 4.03 for each, respectively, they were ranked as moderately polluted to highly polluted and they are the most polluted sampling stations. It was also observed that sampling stations nearer the steel plant are more polluted than others.

http://scialert.net/abstract/?doi=ajaps.2014.552.567 2014/07/07 - 11:12

The study describes the process of implementing a Learning Management System
(LMS) Moodle in training activities. The principle of organization of e-learning
based on open source Moodle was described. It illustrates the process of creating
courses, download lectures, testing in selected Learning Management System Moodle.
Adaptation of Moodle to information resources of educational activity is carried
out. The study also discusses the modernization of the learning process in the
Learning Management System Moodle, allowing partially automate the process of
learning by creating tests for the control of knowledge. Creation module of
questions that gives teachers a tool that can be used based on the lecture material
introduced into the Learning Management System Moodle, to programmatically generate
a certain kind of questions and answers to them.

http://scialert.net/abstract/?doi=ajaps.2014.568.580 2014/07/07 - 11:12

One of the current global challenges is protection of the environment. Due to increased deterioration in overall global ecological safety and the environment’s sharp deterioration in certain countries and regions, the global consequences for outstanding environmental problems indicate that states must unite their efforts to prevent threats to mankind. This study is devoted to some ecological aspects of international customs law. Biodiversity loss, environmental pollution, resource degradation and climate change are among the most serious environmental challenges. The primary objective of this study was to analyze specific examples of international customs law instruments that include relevant prohibitions and restrictions to address such challenges.

http://scialert.net/abstract/?doi=ajaps.2014.581.588 2014/07/07 - 11:12

Most of water supply infrastructures were put in place during India’s
independence period and some pipelines are over 70 years old. Ageing and uncertainty
on its performance under increased and varying demand pattern puts tremendous
pressure on water authorities to rehabilitate the existing system for complete
revamping the system. Complete revamping does not only mount the cost to the
water authority but also makes potential inconvenience to the consumer in terms
of getting new connection with new line. Hence, it is essential to rehabilitate
the pipes which are more sensitive in serving the locality. Rehabilitating the
existing system is generally done by either replacing the existing pipes with
same or higher diameter or laying parallel pipe with existing. The optimal selection
of such a combination is a furious task to water authorities. In the present
study, a combined simulation-optimization modeling approach is developed using
EPANET simulation engine. Differential evolution algorithm is adopted to arrive
at the optimal solution. The demonstration proves that if the required data
are available, the rehabilitation and expansion can be performed in an optimal
manner using the model presented.

http://scialert.net/abstract/?doi=ajaps.2014.375.390 2014/06/16 - 14:10

Most of water supply infrastructures were put in place during India’s
independence period and some pipelines are over 70 years old. Ageing and uncertainty
on its performance under increased and varying demand pattern puts tremendous
pressure on water authorities to rehabilitate the existing system for complete
revamping the system. Complete revamping does not only mount the cost to the
water authority but also makes potential inconvenience to the consumer in terms
of getting new connection with new line. Hence, it is essential to rehabilitate
the pipes which are more sensitive in serving the locality. Rehabilitating the
existing system is generally done by either replacing the existing pipes with
same or higher diameter or laying parallel pipe with existing. The optimal selection
of such a combination is a furious task to water authorities. In the present
study, a combined simulation-optimization modeling approach is developed using
EPANET simulation engine. Differential evolution algorithm is adopted to arrive
at the optimal solution. The demonstration proves that if the required data
are available, the rehabilitation and expansion can be performed in an optimal
manner using the model presented.

http://scialert.net/abstract/?doi=ajaps.2014.375.390 2014/06/16 - 14:10

Air entrainment at the hydraulic structure is considered as one of the economical
means of air-water transmission of atmospheric gases such as nitrogen and oxygen.
The content of Dissolved Oxygen (DO) in the water helps to assess the quality
of water. Enhancing the DO level in water course helps in the survival of terrestrial
animals, fish and other aquatic organisms. More over, oxygen is needed for all
algae, macrophytes and also for numerous chemical reactions that are vital for
stream and lake functioning. Air-water transfer process can be administrated
in the natural flowing channel by providing appropriate stepped cascade according
to the site condition and availability of driving head for flow. The change
in form of energy at the cascade and subsequent formation of turbulence in the
flow at the immediate vicinity of downstream side of structure creates entrainment
of air to water. This study describes the experimental investigation on the
water aeration process at stepped cascade aerator with constant slope for different
water quality flow. Large size stepped cascade aerator model is constructed
in the laboratory to test its performance for three distinct qualities of water.
The data is obtained for different step sizes by keeping slope as constant.

http://scialert.net/abstract/?doi=ajaps.2014.391.402 2014/06/16 - 14:10