Abstract: Industries produce millions of cubic meters of effluent
every year and the wastewater produced may be released into the
surrounding water bodies, treated on-site or at municipal treatment
plants. The determination of organic matter in the wastewater
generated is very important to avoid any negative effect on the
aquatic ecosystem. The scope of the present work is to assess the
physicochemical composition of the wastewater produced from one
of the brewery industry in South Africa. This is to estimate the
environmental impact of its discharge into the receiving water bodies
or the municipal treatment plant. The parameters monitored for the
quantitative analysis of brewery wastewater include biological
oxygen demand (BOD5), chemical oxygen demand (COD), total
suspended solids, volatile suspended solids, ammonia, total oxidized
nitrogen, nitrate, nitrite, phosphorus and alkalinity content. In
average, the COD concentration of the brewery effluent was 5340.97
mg/l with average pH values of 4.0 to 6.7. The BOD5 and the solids
content of the wastewater from the brewery industry were high. This
means that the effluent is very rich in organic content and its
discharge into the water bodies or the municipal treatment plant could
cause environmental pollution or damage the treatment plant. In
addition, there were variations in the wastewater composition
throughout the monitoring period. This might be as a result of
different activities that take place during the production process, as
well as the effects of peak period of beer production on the water
usage.
Abstract: Particle size distribution, the most important
characteristics of aerosols, is obtained through electrical
characterization techniques. The dynamics of charged nanoparticles
under the influence of electric field in Electrical Mobility
Spectrometer (EMS) reveals the size distribution of these particles.
The accuracy of this measurement is influenced by flow conditions,
geometry, electric field and particle charging process, therefore by
the transfer function (transfer matrix) of the instrument. In this work,
a wire-cylinder corona charger was designed and the combined fielddiffusion
charging process of injected poly-disperse aerosol particles
was numerically simulated as a prerequisite for the study of a
multichannel EMS. The result, a cloud of particles with no uniform
charge distribution, was introduced to the EMS. The flow pattern and
electric field in the EMS were simulated using Computational Fluid
Dynamics (CFD) to obtain particle trajectories in the device and
therefore to calculate the reported signal by each electrometer.
According to the output signals (resulted from bombardment of
particles and transferring their charges as currents), we proposed a
modification to the size of detecting rings (which are connected to
electrometers) in order to evaluate particle size distributions more
accurately. Based on the capability of the system to transfer
information contents about size distribution of the injected particles,
we proposed a benchmark for the assessment of optimality of the
design. This method applies the concept of Von Neumann entropy
and borrows the definition of entropy from information theory
(Shannon entropy) to measure optimality. Entropy, according to the
Shannon entropy, is the ''average amount of information contained in
an event, sample or character extracted from a data stream''.
Evaluating the responses (signals) which were obtained via various
configurations of detecting rings, the best configuration which gave
the best predictions about the size distributions of injected particles,
was the modified configuration. It was also the one that had the
maximum amount of entropy. A reasonable consistency was also
observed between the accuracy of the predictions and the entropy
content of each configuration. In this method, entropy is extracted
from the transfer matrix of the instrument for each configuration.
Ultimately, various clouds of particles were introduced to the
simulations and predicted size distributions were compared to the
exact size distributions.
Abstract: Typical load-bearing biological materials like bone,
mineralized tendon and shell, are biocomposites made from both
organic (collagen) and inorganic (biomineral) materials. This
amazing class of materials with intrinsic internally designed
hierarchical structures show superior mechanical properties with
regard to their weak components from which they are formed.
Extensive investigations concentrating on static loading conditions
have been done to study the biological materials failure. However,
most of the damage and failure mechanisms in load-bearing
biological materials will occur whenever their structures are exposed
to dynamic loading conditions. The main question needed to be
answered here is: What is the relation between the layout and
architecture of the load-bearing biological materials and their
dynamic behavior? In this work, a staggered model has been
developed based on the structure of natural materials at nanoscale and
Finite Element Analysis (FEA) has been used to study the dynamic
behavior of the structure of load-bearing biological materials to
answer why the staggered arrangement has been selected by nature to
make the nanocomposite structure of most of the biological materials.
The results showed that the staggered structures will efficiently
attenuate the stress wave rather than the layered structure.
Furthermore, such staggered architecture is effectively in charge of
utilizing the capacity of the biostructure to resist both normal and
shear loads. In this work, the geometrical parameters of the model
like the thickness and aspect ratio of the mineral inclusions selected
from the typical range of the experimentally observed feature sizes
and layout dimensions of the biological materials such as bone and
mineralized tendon. Furthermore, the numerical results validated with
existing theoretical solutions. Findings of the present work emphasize
on the significant effects of dynamic behavior on the natural
evolution of load-bearing biological materials and can help scientists
to design bioinspired materials in the laboratories.
Abstract: Transparent nickel doped cobalt sulfide was fabricated
on a SnO2:F electrode and tested as an efficient electrocatalyst and as
an alternative to the expensive platinum counter electrode. In order to
investigate how this electrode could affect the electrical
characteristics of a dye-sensitized solar cell, we manufactured cells
with the same TiO2 photoanode sensitized with dye (N719) and
employing the same quasi-solid electrolyte, altering only the counter
electrode used. The cells were electrically and electrochemically
characterized and it was observed that the ones with the Ni doped
CoS2 outperformed the efficiency of the cells with the Pt counter
electrode (3.76% and 3.44% respectively). Particularly, the higher
efficiency of the cells with the Ni doped CoS2 counter electrode (CE)
is mainly because of the enhanced photocurrent density which is
attributed to the enhanced electrocatalytic ability of the CE and the
low charge transfer resistance at the CE/electrolyte interface.
Abstract: Distillery spentwash contains high chemical oxygen
demand (COD), biological oxygen demand (BOD), color, total
dissolved solids (TDS) and other contaminants even after biological
treatment. The effluent can’t be discharged as such in the surface
water bodies or land without further treatment. Reverse osmosis (RO)
treatment plants have been installed in many of the distilleries at
tertiary level in many of the distilleries in India, but are not properly
working due to fouling problem which is caused by the presence of
high concentration of organic matter and other contaminants in
biologically treated spentwash. In order to make the membrane
treatment a proven and reliable technology, proper pre-treatment is
mandatory. In the present study, ultra-filtration (UF) for pretreatment
of RO at tertiary stage has been performed. Operating
parameters namely initial pH (pHo: 2–10), trans-membrane pressure
(TMP: 4-20 bars) and temperature (T: 15-43°C) were used for
conducting experiments with UF system. Experiments were
optimized at different operating parameters in terms of COD, color,
TDS and TOC removal by using response surface methodology
(RSM) with central composite design. The results showed that
removal of COD, color and TDS was 62%, 93.5% and 75.5%
respectively, with UF, at optimized conditions with increased
permeate flux from 17.5 l/m2/h (RO) to 38 l/m2/h (UF-RO). The
performance of the RO system was greatly improved both in term of
pollutant removal as well as water recovery.
Abstract: The goal of this experiment is to evaluate the
effectiveness of different leachate pre-treatment options in terms of
COD and ammonia removal. This research focused on the evaluation
of physical-chemical methods for pre-treatment of leachate that
would be effective and rapid in order to satisfy the requirements of
the sewer discharge by-laws. The four pre-treatment options
evaluated were: air stripping, chemical coagulation, electrocoagulation
and advanced oxidation with sodium ferrate. Chemical
coagulation reported the best COD removal rate at 43%, compared to
18% for both air stripping and electro-coagulation, and 20% for
oxidation with sodium ferrate. On the other hand, air stripping was
far superior to the other treatment options in terms of ammonia
removal with 86%. Oxidation with sodium ferrate reached only 16%,
while chemical coagulation and electro-coagulation removed less
than 10%. When combined, air stripping and chemical coagulation
removed up to 50% COD and 85% ammonia.
Abstract: Waste Load Allocation (WLA) strategies usually
intend to find economic policies for water resource management.
Water quality trading (WQT) is an approach that uses discharge
permit market to reduce total environmental protection costs. This
primarily requires assigning discharge limits known as total
maximum daily loads (TMDLs). These are determined by monitoring
organizations with respect to the receiving water quality and
remediation capabilities. The purpose of this study is to compare two
approaches of TMDL assignment for WQT policy in small catchment
area of Haraz River, in north of Iran. At first, TMDLs are assigned
uniformly for the whole point sources to keep the concentrations of
BOD and dissolved oxygen (DO) at the standard level at checkpoint
(terminus point). This was simply simulated and controlled by
Qual2kw software. In the second scenario, TMDLs are assigned
using multi objective particle swarm optimization (MOPSO) method
in which the environmental violation at river basin and total treatment
costs are minimized simultaneously. In both scenarios, the equity
index and the WLA based on trading discharge permits (TDP) are
calculated. The comparative results showed that using economically
optimized TMDLs (2nd scenario) has slightly more cost savings rather
than uniform TMDL approach (1st scenario). The former annually
costs about 1 M$ while the latter is 1.15 M$. WQT can decrease
these annual costs to 0.9 and 1.1 M$, respectively. In other word,
these approaches may save 35 and 45% economically in comparison
with command and control policy. It means that using multi objective
decision support systems (DSS) may find more economical WLA,
however its outcome is not necessarily significant in comparison with
uniform TMDLs. This may be due to the similar impact factors of
dischargers in small catchments. Conversely, using uniform TMDLs
for WQT brings more equity that makes stakeholders not feel that
much envious of difference between TMDL and WQT allocation. In
addition, for this case, determination of TMDLs uniformly would be
much easier for monitoring. Consequently, uniform TMDL for TDP
market is recommended as a sustainable approach. However,
economical TMDLs can be used for larger watersheds.
Abstract: Construction projects are information intensive in
nature and involve many activities that are related to each other.
Wireless technologies can be used to improve the accuracy and
timeliness of data collected from construction sites and shares it with
appropriate parties. Nonetheless, the construction industry tends to be
conservative and shows hesitation to adopt new technologies. A main
concern for owners, contractors or any person in charge on a job site
is the cost of the technology in question. Wireless technologies are
not cheap. There are a lot of expenses to be taken into consideration,
and a study should be completed to make sure that the importance
and savings resulting from the usage of this technology is worth the
expenses. This research attempts to assess the effectiveness of using
the appropriate wireless technologies based on criteria such as
performance, reliability, and risk. The assessment is based on a utility
function model that breaks down the selection issue into alternatives
attribute. Then the attributes are assigned weights and single
attributes are measured. Finally, single attribute are combined to
develop one single aggregate utility index for each alternative.
Abstract: In this work new macroporous Ni electrodes modified
with Au nanoparticles for hydrogen production have been developed.
The supporting macroporous Ni electrodes have been obtained by
means of the electrodeposition at high current densities. Then, the Au
nanoparticles were synthesized and added to the electrode surface.
The electrocatalytic behaviour of the developed electrocatalysts was
studied by means of pseudo-steady-state polarization curves,
electrochemical impedance spectroscopy (EIS) and hydrogen
discharge curves. The size of the Au synthetized nanoparticles shows
a monomodal distribution, with a very sharp band between 10 and 50
nm. The characteristic parameters d10, d50 and d90 were 14, 20 and
31 nm respectively. From Tafel polarization data has been concluded
that the Au nanoparticles improve the catalytic activity of the
developed electrodes towards the HER respect to the macroporous Ni
electrodes. EIS permits to obtain the electrochemically active area by
means of the roughness factor value. All the developed electrodes
show roughness factor values in the same order of magnitude. From
the activation energy results it can be concluded that the Au
nanoparticles improve the intrinsic catalytic activity of the
macroporous Ni electrodes.
Abstract: Let us consider that the entire universe is composed of
a single hydrogen atom within which the electron is moving around
the proton. In this case, according to classical theories of physics,
radiation, photons respectively, should be absorbed by the electron.
Depending on the number of photons absorbed, the electron radius of
rotation around the proton is established. Until now, the principle of
photons absorption by electrons and the electron transition to a new
energy level, namely to a higher radius of rotation around the proton,
is not clarified in physics. This paper aims to demonstrate that
radiation, photons respectively, have mass and negative electrostatic
charge similar to electrons but infinitely smaller. The experiments
which demonstrate this theory are simple: thermal expansion,
photoelectric effect and thermonuclear reaction.
Abstract: This article aims to analyze the static stability and
pseudostatic slope by using different methods such as: Bishop
method, Junbu, Ordinary, Morgenstern-price and GLE. The two
dimensional modeling of slope stability under various loading as: the
earthquake effect, the water level and road mobile charges. The
results show that the slope is stable in the static case without water,
but in other cases, the slope lost its stability and give unstable. The
calculation of safety factor is to evaluate the stability of the slope
using the limit equilibrium method despite the difference between the
results obtained by these methods that do not rely on the same
assumptions. In the end, the results of this study illuminate well the
influence of the action of water, moving loads and the earthquake on
the stability of the slope.
Abstract: In this paper, we proposed a novel SCR (Silicon Controlled
Rectifier) - based ESD (Electrostatic Discharge) protection device for I/O
and power clamp. The proposed device has a higher holding voltage
characteristic than conventional SCR. These characteristics enable to have
latch-up immunity under normal operating conditions as well as superior full
chip ESD protection. The proposed device was analyzed to figure out
electrical characteristics and tolerance robustness in term of individual
design parameters (D1, D2, D3). They are investigated by using the
Synopsys TCAD simulator. As a result of simulation, holding voltage
increased with different design parameters. The holding voltage of the
proposed device changes from 3.3V to 7.9V. Also, N-Stack structure ESD
device with the high holding voltage is proposed. In the simulation results,
2-stack has holding voltage of 6.8V and 3-stack has holding voltage of
10.5V. The simulation results show that holding voltage of stacking
structure can be larger than the operation voltage of high-voltage
application.
Abstract: Hybrid electric vehicles can reduce pollution and
improve fuel economy. Power-split hybrid electric vehicles (HEVs)
provide two power paths between the internal combustion engine
(ICE) and energy storage system (ESS) through the gears of an
electrically variable transmission (EVT). EVT allows ICE to operate
independently from vehicle speed all the time. Therefore, the ICE can
operate in the efficient region of its characteristic brake specific fuel
consumption (BSFC) map. The two-mode powertrain can operate in
input-split or compound-split EVT modes and in four different fixed
gear configurations. Power-split architecture is advantageous because
it combines conventional series and parallel power paths. This
research focuses on input-split and compound-split modes in the
two-mode power-split powertrain. Fuzzy Logic Control (FLC) for an
internal combustion engine (ICE) and PI control for electric machines
(EMs) are derived for the urban driving cycle simulation. These
control algorithms reduce vehicle fuel consumption and improve ICE
efficiency while maintaining the state of charge (SOC) of the energy
storage system in an efficient range.
Abstract: This paper deals with the study of reflection and
transmission characteristics of acoustic waves at the interface of a
semiconductor half-space and elastic solid. The amplitude ratios
(reflection and transmission coefficients) of reflected and transmitted
waves to that of incident wave varying with the incident angles have
been examined for the case of quasi-longitudinal wave. The special
cases of normal and grazing incidence have also been derived with
the help of Gauss elimination method. The mathematical model
consisting of governing partial differential equations of motion and
charge carriers’ diffusion of n-type semiconductors and elastic solid
has been solved both analytically and numerically in the study. The
numerical computations of reflection and transmission coefficients
has been carried out by using MATLAB programming software for
silicon (Si) semiconductor and copper elastic solid. The computer
simulated results have been plotted graphically for Si
semiconductors. The study may be useful in semiconductors,
geology, and seismology in addition to surface acoustic wave (SAW)
devices.
Abstract: Removal of the widespread used drug paracetamol
from water was investigated using activated carbon originated from
dende coconut mesocarp and babassu coconut mesocarp. Kinetic and
equilibrium data were obtained at different values of pH. Both
activated carbons showed high efficiency when pH ≤ pHPZC as the
carbonil group of paracetamol molecule are adsorbed due to
positively charged carbon surface. Microporosity also played an
important role in such process. Pseudo-second order model was better
adjusted to the kinetic results. Equilibrium data may be represented
by Langmuir equation.
Abstract: In the present work, Electrochemical Impedance
Spectrocopy (EIS) is applied to study the transport of different metal
cations through a cation-exchange membrane. This technique enables
the identification of the ionic-transport characteristics and to
distinguish between different transport mechanisms occurring at
different current density ranges. The impedance spectra are
dependent on the applied dc current density, on the type of cation and
on the concentration.
When the applied dc current density increases, the diameter of the
impedance spectra loops increases because all the components of
membrane system resistance increase. The diameter of the impedance
plots decreases in the order of Na(I), Ni(II) and Cr(III) due to the
increased interactions between the negatively charged sulfonic
groups of the membrane and the cations with greater charge. Nyquist
plots are shifted towards lower values of the real impedance, and its
diameter decreases with the increase of concentration due to the
decrease of the solution resistance.
Abstract: Coal is an important non-renewable energy source of
and can be associated with radioactive elements. In Figueira city,
Paraná state, Brazil, it was recorded high uranium activity near the
coal mine that supplies a local thermoelectric power plant. In this
context, the radon activity (Rn-222, produced by the Ra-226 decay in
the U-238 natural series) was evaluated in groundwater, river water
and effluents produced from the acid mine drainage in the coal reject
dumps. The samples were collected in August 2013 and in February
2014 and analyzed at LABIDRO (Laboratory of Isotope and
Hydrochemistry), UNESP, Rio Claro city, Brazil, using an alpha
spectrometer (AlphaGuard) adjusted to evaluate the mean radon
activity concentration in five cycles of 10 minutes. No radon activity
concentration above 100 Bq.L-1, which was a previous critic value
established by the World Health Organization. The average radon
activity concentration in groundwater was higher than in surface
water and in effluent samples, possibly due to the accumulation of
uranium and radium in the aquifer layers that favors the radon
trapping. The lower value in the river waters can indicate dilution and
the intermediate value in the effluents may indicate radon absorption
in the coal particles of the reject dumps. The results also indicate that
the radon activities in the effluents increase with the sample
acidification, possibly due to the higher radium leaching and the
subsequent radon transport to the drainage flow. The water samples
of Laranjinha River and Ribeirão das Pedras stream, which,
respectively, supply Figueira city and receive the mining effluent,
exhibited higher pH values upstream the mine, reflecting the acid
mine drainage discharge. The radionuclides transport indicates the
importance of monitoring their activity concentration in natural
waters due to the risks that the radioactivity can represent to human
health.
Abstract: This study was carried out to investigate the adverse
effect of industrial wastewater on surface water quality in Gebeng
industrial estate, Pahang, Malaysia. Surface water was collected from
six sampling stations. Physicochemical parameters were
characterized based on in-situ and ex-situ analysis according to
standard methods by American Public Health Association (APHA).
Selected heavy metals were determined by using Inductively Coupled
Plasma Mass Spectrometry (ICP MS). The results revealed that the
concentration of heavy metals such as Pb, Cu, Cd, Cr and Hg were
high in samples. The results also showed that the value of Pb and Hg
were higher in the wet season in comparison to dry season.
According to Malaysia National Water Quality Standard (NWQS)
and Water Quality Index (WQI) all the sampling station were
categorized as class IV (highly polluted). The present study revealed
that the adverse effects of careless disposal of wastes and directly
discharge of effluents affected on surface water quality. Therefore,
the authorities should implement the laws to ensure the proper
practices of wastewater management for environmental sustainability
around the study area.
Abstract: The capability of exploiting the electronic charge and
spin properties simultaneously in a single material has made diluted
magnetic semiconductors (DMS) remarkable in the field of
spintronics. We report the designing of DMS based on zinc-blend
ZnO doped with Cr impurity. The full potential linearized augmented
plane wave plus local orbital FP-L(APW+lo) method in density
functional theory (DFT) has been adapted to carry out these
investigations. For treatment of exchange and correlation energy,
generalized gradient approximations have been used. Introducing Cr
atoms in the matrix of ZnO has induced strong magnetic moment
with ferromagnetic ordering at stable ground state. Cr:ZnO was found
to favor the short range magnetic interaction that
reflect tendency of Cr clustering. The electronic structure of ZnO is
strongly influenced in the presence of Cr impurity atoms where
impurity bands appear in the band gap.
Abstract: The textile industry plays a major role in the economy
of India and on the other side of the coin it is the major source for
water pollution. As azo dyes is the largest dye class they are
extensively used in many fields such as textile industry, leather
tanning industry, paper production, food, color photography,
pharmaceuticals and medicine, cosmetic, hair colorings, wood
staining, agricultural, biological and chemical research etc. In
addition to these, they can have acute and/or chronic effects on
organisms depending on their concentration and length of exposure
when they discharged as effluent in the environment. The aim of this
study was to assess the genotoxic and histotoxic potentials of
environmentally relevant concentrations of C. I. Reactive Red 120
(RR 120) on Catla catla, important edible freshwater fingerlings. For
this, healthy Catla catla fingerlings were procured from the
Government Fish Farm and acclimatized in 100 L capacity and
continuously aerated glass aquarium in laboratory for 15 days.
According to APHA some physic-chemical parameters were
measured and maintained such as temperature, pH, dissolve oxygen,
alkalinity, total hardness. Water along with excreta had been changed
every 24 hrs. All fingerlings were fed artificial food palates once a
day @ body weight. After 15 days fingerlings were grouped in 5 (10
in each) and exposed to various concentrations of RR 120 (Control,
10, 20, 30 and 40 mg.l-1) and samples (peripheral blood and gills,
kidney) were collected and analyzed at 96 hrs. All results were
compared with the control. Micronuclei (MN), nuclear buds (NB),
fragmented-apoptotic (FA) and bi-nucleated (BN) cells in blood
smears and in tissues (gills and kidney cells) were observed.
Prominent histopathological alterations were noticed in gills such as
aneurism, hyperplasia, degenerated central axis, lifting of gill
epithelium, curved secondary gill lamellae etc. Similarly kidney
showed some detrimental changes like shrunken glomeruli with
increased periglomerular space, degenerated renal tubules etc. Both
haematological and histopathological changes clearly reveal the toxic
potential of RR 120. This work concludes that water pollution
assessment can be done by these two biomarkers which provide
baseline to the further chromosomal or molecular work.