Abstract: In this paper we consider the equation of motion for
the F (R, T) gravity on their property of conformal invariance. It
is shown that in the general case, such a theory is not conformal
invariant. Studied special cases for the functions v and u in which
can appear properties of the theory. Also we consider cosmological
aspects F (R, T) theory of gravity, having considered particular case
F (R, T) = μR+νT^2. Showed that in this case there is a nonlinear
dependence of the parameter equation of state from time to time,
which affects its evolution.
Abstract: This study is to fill up a research gap on examining the
differences in normative beliefs (namely acceptance of weaknesses,
acceptance of provoked aggression, and acceptance of unprovoked
aggression) among different subtypes of aggressors and
non-aggressors (reactive aggressors, proactive aggressors,
reactive-proactive aggressors, and non-aggressors). 2,236 students
(1,372 males and 864 females), aged from 11 to 18, completed a
self-reported questionnaire. Results revealed that (a) schoolchildren
with reactive-proactive aggression have the highest acceptance of
provoked aggression, the highest acceptance of unprovoked
aggression, and the lowest acceptance of weakness; (b) schoolchildren
with proactive aggression have higher acceptance of unprovoked
aggression and lower acceptance of weakness than reactive aggressors;
and (c) schoolchildren without aggression have the lowest acceptance
of provoked aggression, the lowest acceptance of unprovoked
aggression, and the highest acceptance of weakness.
Abstract: The development of allometric models is crucial to
accurate forest biomass/carbon stock assessment. The aim of this
study was to develop a set of biomass prediction models that will
enable the determination of total tree aboveground biomass for
savannah woodland area in Niger State, Nigeria. Based on the data
collected through biometric measurements of 1816 trees and
destructive sampling of 36 trees, five species specific and one site
specific models were developed. The sample size was distributed
equally between the five most dominant species in the study site
(Vitellaria paradoxa, Irvingia gabonensis, Parkia biglobosa,
Anogeissus leiocarpus, Pterocarpus erinaceous). Firstly, the
equations were developed for five individual species. Secondly these
five species were mixed and were used to develop an allometric
equation of mixed species. Overall, there was a strong positive
relationship between total tree biomass and the stem diameter. The
coefficient of determination (R2 values) ranging from 0.93 to 0.99 P
< 0.001 were realised for the models; with considerable low standard
error of the estimates (SEE) which confirms that the total tree above
ground biomass has a significant relationship with the dbh. F-test
values for the biomass prediction models were also significant at p
Abstract: Activated carbons (M4P0, M4P2, and M5P2) used in
this research were produced from palm shell and polyetherether
ketone (PEEK) via carbonization, impregnation and microwave
activation. The adsorption/desorption process was carried out using
static volumetric adsorption. Regeneration is important in the overall
economy of the process and waste minimization. This work focuses
on the thermal regeneration of the CO2 exhausted microwave
activated carbons. The regeneration strategy adopted was thermal
with nitrogen purge desorption with N2 feed flow rate of 20 ml/min
for 1 h at atmospheric pressure followed by drying at 150oC.Seven
successive adsorption/regeneration processes were carried out on the
material. It was found that after seven adsorption regeneration cycles;
the regeneration efficiency (RE) for CO2 activated carbon from palm
shell only (M4P0) was more than 90% while that of hybrid palm
shell-PEEK (M4P2, M5P2) was above 95%. The cyclic adsorption
and regeneration shows the stability of the adsorbent materials.
Abstract: Surface modification and functionalization has been
an important tool for scientists in order to open new frontiers in
nanoscience and nanotechnology. Desired surface characteristics for
the intended applications can be achieved with surface
functionalization.
In this work, the effect of water soluble ligands on the adsorption
capabilities of silver nanoparticles onto AC which was synthesized
from German beech wood was investigated. Sodium borohydride
(NaBH4) and polyvinyl alcohol (PVA) were used as the ligands.
Silver nanoparticles with different surface coatings have average
sizes range from 10 to 13 nm. They were synthesized in aqueous
media by reducing Ag (I) ion in the presence of ligands. These
particles displayed adsorption tendencies towards AC when they
were mixed together and shaken in distilled water.
Silver nanoparticles (NaBH4-AgNPs) reduced and stabilized by
NaBH4 adsorbed onto AC with a homogenous dispersion of
aggregates with sizes in the range of 100-400 nm. Beside, silver
nanoparticles, which were prepared in the presence of both NaBH4
and PVA (NaBH4/PVA-Ag NPs), demonstrated that NaBH4/PVA-Ag
NPs adsorbed and dispersed homogenously but, they aggregated with
larger sizes on the AC surface (range from 300 to 600 nm). In
addition, desorption resistance of Ag nanoparticles were investigated
in distilled water. According to the results AgNPs were not desorbed
on the AC surface in distilled water.
Abstract: In this paper, the author studied the possibilities of
using Rice Husk Ash (RHA) available in India; to produce concrete.
Experiments conducted with RHA obtained from West Bengal, India;
to replace cement partially to produce concrete of grade M10, M15,
M20, M25 and M30. The concrete produced in the laboratory by
replacing cement by 5%, 10%, 15%, 20%, 25% and 30% RHA.
Compressive strength tests carried out to determine the strength of
concrete. Cost analysis and comparison done to show the cost
effectiveness of RHA Concrete. Traditional uses of Rice Husk in
India pointed out and the advantages of using RHA in making
concrete highlighted. Suggestion provided regarding prospective
application of RHA concrete in India; which in turn will definitely
reduce the cost of concrete and environmental friendly due to
utilization of waste and replacement of Cement.
Abstract: A new concept of response system is proposed for
filling the gap that exists in reducing vulnerability during immediate
response to natural disasters. Real Time Early Response Systems
(RTERSs) incorporate real time information as feedback data for
closing control loop and for generating real time situation assessment.
A review of the state of the art on works that fit the concept of
RTERS is presented, and it is found that they are mainly focused on
manmade disasters. At the same time, in response phase of natural
disaster management many works are involved in creating early
warning systems, but just few efforts have been put on deciding what
to do once an alarm is activated. In this context a RTERS arises as a
useful tool for supporting people in their decision making process
during natural disasters after an event is detected, and also as an
innovative context for applying well-known automation technologies
and automatic control concepts and tools.
Abstract: Potato (Solanum tuberosum L.) is one of the major
vegetable crops that are grown world –wide because of its economic
importance. This experiment investigated the effect of local sands
(River Base, Al-Ekader and Karbala) on number and total weight of
minitubers. Statistical analysis revealed that there were no significant
differences among sand cultures in number of stem/plant, chlorophyll
index and tubers dry weight. River Base sand had the highest plant
height (74.9 cm), leaf number/plant number (39.3), leaf area (84.4
dcm2⁄plant), dry weight/plant (26.31), tubers number/plant (8.5),
tubers weight/plant (635.53 gm) and potato tuber yields/trove (28.60
kg), whereas the Karbala sand had lower performance. All the
characters had positive and significant correlation with yields except
the traits number of stem and tuber dry weight.
Abstract: The seismic responses of steel buildings with semirigid
post-tensioned connections (PC) are estimated and compared
with those of steel buildings with typical rigid (welded) connections
(RC). The comparison is made in terms of global and local response
parameters. The results indicate that the seismic responses in terms of
interstory shears, roof displacements, axial load and bending
moments are smaller for the buildings with PC connection. The
difference is larger for global than for local parameters, which in turn
varies from one column location to another. The reason for this
improved behavior is that the buildings with PC dissipate more
hysteretic energy than those with RC. In addition, unlike the case of
buildings with WC, for the PC structures the hysteretic energy is
mostly dissipated at the connections, which implies that structural
damage in beams and columns is not significant. According to these
results, steel buildings with PC are a viable option in high seismicity
areas because of their smaller response and self-centering connection
capacity as well as the fact that brittle failure is avoided.
Abstract: The aim of this work is to build a model based on
tissue characterization that is able to discriminate pathological and
non-pathological regions from three-phasic CT images. With our
research and based on a feature selection in different phases, we are
trying to design a neural network system with an optimal neuron
number in a hidden layer. Our approach consists of three steps:
feature selection, feature reduction, and classification. For each
region of interest (ROI), 6 distinct sets of texture features are
extracted such as: first order histogram parameters, absolute gradient,
run-length matrix, co-occurrence matrix, autoregressive model, and
wavelet, for a total of 270 texture features. When analyzing more
phases, we show that the injection of liquid cause changes to the high
relevant features in each region. Our results demonstrate that for
detecting HCC tumor phase 3 is the best one in most of the features
that we apply to the classification algorithm. The percentage of
detection between pathology and healthy classes, according to our
method, relates to first order histogram parameters with accuracy of
85% in phase 1, 95% in phase 2, and 95% in phase 3.
Abstract: In this research (using induction furnace process)
nodular iron with three different percentages of copper (residual,
0.5% and 1,2%) was obtained. Chemical analysis was performed by
mass spectrometry and microstructures were characterized by Optical
Microscopy (ASTM E3) and Scanning Electron Microscopy (SEM).
The study of mechanical behavior was carried out in a mechanical
test machine (ASTM E8) and a Pin on disk tribometer (ASTM G99)
was used to assess wear resistance. It is observed that the dissolution
of copper in crystal lattice increases the pearlite structure improving
the wear and hardness behavior, but producing a contrary effect on
the energy absorption.
Abstract: Composite material based on Fe3Si micro-particles
and Mn-Zn nano-ferrite was prepared using powder metallurgy
technology. The sol-gel followed by autocombustion process was
used for synthesis of Mn0.8Zn0.2Fe2O4 ferrite. 3 wt.% of mechanically
milled ferrite was mixed with Fe3Si powder alloy. Mixed micro-nano
powder system was homogenized by the Resonant Acoustic Mixing
using ResodynLabRAM Mixer. This non-invasive homogenization
technique was used to preserve spherical morphology of Fe3Si
powder particles. Uniaxial cold pressing in the closed die at pressure
600 MPa was applied to obtain a compact sample. Microwave
sintering of green compact was realized at 800°C, 20 minutes, in air.
Density of the powders and composite was measured by
Hepycnometry. Impulse excitation method was used to measure
elastic properties of sintered composite. Mechanical properties were
evaluated by measurement of transverse rupture strength (TRS) and
Vickers hardness (HV). Resistivity was measured by 4 point probe
method. Ferrite phase distribution in volume of the composite was
documented by metallographic analysis.
It has been found that nano-ferrite particle distributed among
micro- particles of Fe3Si powder alloy led to high relative density
(~93%) and suitable mechanical properties (TRS >100 MPa, HV
~1GPa, E-modulus ~140 GPa) of the composite. High electric
resistivity (R~6.7 ohm.cm) of prepared composite indicate their
potential application as soft magnetic material at medium and high
frequencies.
Abstract: The development of the United Arab Emirates (UAE)
into a regional trade, tourism, finance and logistics hub has
transformed its real estate markets. However, speculative activity and
price volatility remain concerns. UAE residential market values
(MV) are exposed to fluctuations in capital flows and migration
which, in turn, are affected by geopolitical uncertainty, oil price
volatility and global investment market sentiment. Internally, a
complex interplay between administrative boundaries, land tenure,
building quality and evolving location characteristics fragments UAE
residential property markets. In short, the UAE Residential Valuation
System (UAE-RVS) confronts multiple challenges to collect, filter
and analyze relevant information in complex and dynamic spatial and
capital markets. A robust (RVS) can mitigate the risk of unhelpful
volatility, speculative excess or investment mistakes. The research
outlines the institutional, ontological, dynamic and epistemological
issues at play. We highlight the importance of system capabilities,
valuation standard salience and stakeholders trust.
Abstract: This study examines analytically the effect of tsunami loads on reinforced concrete (RC) frame buildings. The impact of tsunami wave loads and waterborne objects are analyzed using a typical substandard full-scale two-story RC frame building tested as part of the EU-funded Ecoleader project. The building was subjected to shake table tests in bare condition, and subsequently strengthened using Carbon Fiber Reinforced Polymers (CFRP) composites and retested. Numerical models of the building in both bare and CFRP-strengthened conditions are calibrated in DRAIN-3DX software to match the test results. To investigate the response of wave loads and impact forces, the numerical models are subjected to nonlinear dynamic analyses using force time-history input records. The analytical results are compared in terms of displacements at the floors and at the “impact point” of a boat. The results show that the roof displacement of the CFRP-strengthened building reduced by 63% when compared to the bare building. The results also indicate that strengthening only the mid-height of the impact column using CFRP is more effective at reducing damage when compared to strengthening other parts of the column. Alternative solutions to mitigate damage due to tsunami loads are suggested.
Abstract: Biofuels production has come forth as a future
technology to combat the problem of depleting fossil fuels. Bio-based
ethanol production from enzymatic lignocellulosic biomass
degradation serves an efficient method and catching the eye of
scientific community. High cost of the enzyme is the major obstacle
in preventing the commercialization of this process. Thus main
objective of the present study was to optimize composition of
medium components for enhancing cellulase production by newly
isolated strain of Bacillus tequilensis. Nineteen factors were taken
into account using statistical Plackett-Burman Design. The significant
variables influencing the cellulose production were further employed
in statistical Response Surface Methodology using Central
Composite Design for maximizing cellulase production. The
optimum medium composition for cellulase production was: peptone
(4.94 g/L), ammonium chloride (4.99 g/L), yeast extract (2.00 g/L),
Tween-20 (0.53 g/L), calcium chloride (0.20 g/L) and cobalt chloride
(0.60 g/L) with pH 7, agitation speed 150 rpm and 72 h incubation at
37oC. Analysis of variance (ANOVA) revealed high coefficient of
determination (R2) of 0.99. Maximum cellulase productivity of 11.5
IU/ml was observed against the model predicted value of 13 IU/ml.
This was found to be optimally active at 60oC and pH 5.5.
Abstract: This study evaluated the use of raw or processed
Prosopis juliflora (Meskit) pods as a major ingredient in a formulated
ration to provide an alternative non-conventional concentrate for
livestock feeding in Oman. Dry Meskit pods were reduced to lengths
of 0.5- 1.0 cm to ensure thorough mixing into three diets. Meskit
pods were subjected to two types of treatments; roasting and soaking.
They were roasted at 150оC for 30 minutes using a locally-made
roasting device (40 kg barrel container rotated by electric motor and
heated by flame gas cooker). Chopped pods were soaked in tap water
for 24 hours and dried for 2 days under the sun with frequent turning.
The Meskit-pod-based diets (MPBD) were formulated and pelleted
from 500 g/kg ground Meskit pods, 240 g/kg wheat bran, 200 g/kg
barley grain, 50 g/kg local dried sardines and 10 g/kg of salt. Twenty
four 10 months-old intact Omani male lambs with average body
weight of 27.3 kg (± 0.5 kg) were used in a feeding trial for 84 days.
They were divided (on body weight basis) and allocated to four diet
combination groups. These were: Rhodes grass hay (RGH) plus a
general ruminant concentrate (GRC); RGH plus raw Meskit pods
(RMP) based concentrate; RGH plus roasted Meskit pods (ROMP)
based concentrate; RGH plus soaked Meskit pods (SMP) based
concentrate Daily feed intakes and bi-weekly body weights were
recorded. MPBD had higher contents of crude protein (CP), acid
detergent fibre (ADF) and neutral detergent fibre (NDF) than the
GRC. Animals fed various types of MPBD did not show signs of ill
health. There was a significant effect of feeding ROMP on the
performance of Omani sheep compared to RMP and SMP. The
ROMP fed animals had similar performance to those fed the GRC in
terms of feed intake, body weight gain and feed conversion ratio
(FCR).This study indicated that roasted Meskit pods based diet may
be used instead of the commercial concentrate for feeding Omani
sheep without adverse effects on performance. It offers a cheap
alternative source of protein and energy for feeding Omani sheep.
Also, it might help in solving the spread impact of Meskit trees,
maintain the ecosystem and helping in preserving the local tree
species.
Abstract: The aim of this paper is to perform experimental
modal analysis (EMA) of reinforced concrete (RC) square slabs.
EMA is the process of determining the modal parameters (Natural
Frequencies, damping factors, modal vectors) of a structure from a
set of frequency response functions FRFs (curve fitting). Although,
experimental modal analysis (or modal testing) has grown steadily in
popularity since the advent of the digital FFT spectrum analyzer in
the early 1970’s, studying all types of members and materials using
such method have not yet been well documented. Therefore, in this
work, experimental tests were conducted on RC square slab
specimens of dimensions 600mm x 600mmx 40mm. Experimental
analysis was based on freely supported boundary condition.
Moreover, impact testing as a fast and economical means of finding
the modes of vibration of a structure was used during the
experiments. In addition, Pico Scope 6 device and MATLAB
software were used to acquire data, analyze and plot Frequency
Response Function (FRF). The experimental natural frequencies
which were extracted from measurements exhibit good agreement
with analytical predictions. It is showed that EMA method can be
usefully employed to investigate the dynamic behavior of RC slabs.
Abstract: PLA emerged as a promising polymer because of its
property as a compostable, biodegradable thermoplastic made from
renewable sources. PLA can be polymerized from monomers
(Lactide or Lactic acid) obtained by fermentation processes from
renewable sources such as corn starch or sugarcane. For PLA
synthesis, ring opening polymerization (ROP) of Lactide monomer is
one of the preferred methods. In the literature, the technique mainly
developed for ROP of PLA is based on metal/bimetallic catalyst (Sn,
Zn and Al) or other organic catalysts in suitable solvent. However,
the PLA synthesized using such catalysts may contain trace elements
of the catalyst which may cause toxicity. This work estimated the
usefulness and drawbacks of using different catalysts as well as effect
of alternative energies and future aspects for PLA production.
Abstract: Thin ZnO films are deposited on glass substrates via
sol–gel method and dip-coating. The films are prepared from zinc
acetate dehydrate as a starting reagent. After that the as-prepared
ZnO sol is aged for different periods (0, 1, 3, 5, 10, 15 and 30 days).
Nanocrystalline thin films are deposited from various sols. The
effect ZnO sols aging time on the structural and photocatalytic
properties of the films is studied. The films surface is studied by
Scanning Electron Microscopy. The effect of the aging time of the
starting solution is studied in the photocatalytic degradation of
Reactive Black 5 (RB5) by UV-vis spectroscopy. The experiments
are conducted upon UV-light illumination and in complete darkness.
The variation of the absorption spectra shows the degradation of RB5
dissolved in water, as a result of the reaction, occurring on the surface
of the films and promoted by UV irradiation. The initial
concentrations of dye (5, 10 and 20 ppm) and the effect of the aging
time are varied during the experiments. The results show, that the
increasing aging time of starting solution with respect to ZnO
generally promotes photocatalytic activity. The thin films obtained
from ZnO sol, which is aged 30 days have best photocatalytic
degradation of the dye (97,22%) in comparison with the freshly
prepared ones (65,92%). The samples and photocatalytic
experimental results are reproducible. Nevertheless, all films exhibit
a substantial activity in both UV light and darkness, which is
promising for the development of new ZnO photocatalysts by sol-gel
method.
Abstract: Since columns are the most important elements of the
structures, failure of one column in a critical location can cause a
progressive collapse. In this respect, the repair and strengthening of
columns is a very important subject to reduce the building failure and
to keep the columns capacity. Twenty columns with different
parameters is tested and analysis. Eleven typical confined reinforced
concrete (RC) columns with different types of techniques are
assessment. And also, four confined concrete columns with plastic
tube (PVC) are tested with and with four paralleling tested of
unconfined plain concrete. The techniques of confined RC columns
are mortar strengthening, Steel rings strengthening, FRP
strengthening. Moreover, the technique of confined plain concrete
(PC) column is used PVC tubes. The columns are tested under
uniaxial compressive loads studied the effect of confinement on the
structural behavior of circular RC columns. Test results for each
column are presented in the form of crack patterns, stress-strain
curves. Test results show that confining of the RC columns using
different techniques of strengthening results significant improvement
of the general behavior of the columns and can used in construction.
And also, tested confined PC columns with PVC tubes results shown
that the confined PC with PVC tubes can be used in economical
building. The theoretical model for predicted column capacity is
founded with experimental factor depends on the confined techniques
used and the strain reduction.