Abstract: It is an established fact that polymers have several
physical limitations such as low stiffness and low resistance to
impact on loading. Hence, polymers do not usually have requisite
mechanical strength for application in various fields. The
reinforcement by high strength fibers provides the polymer
substantially enhanced mechanical properties and makes them more
suitable for a large number of diverse applications. This research
evaluates the effects of particulate Cow bone and Groundnut shell
additions on the mechanical properties and microstructure of cow
bone and groundnut shell reinforced epoxy composite in order to
assess the possibility of using it as a material for engineering
applications. Cow bone and groundnut shell particles reinforced with
epoxy (CBRPC and GSRPC) was prepared by varying the cow bone
and groundnut shell particles from 0-25 wt% with 5 wt% intervals. A
Hybrid of the Cow bone and Groundnut shell (HGSCB) reinforce
with epoxy was also prepared. The mechanical properties of the
developed composites were investigated. Optical microscopy was
used to examine the microstructure of the composites. The results
revealed that mechanical properties did not increase uniformly with
additions in filler but exhibited maximum properties at specific
percentages of filler additions. From the Microscopic evaluation, it
was discovered that homogeneity decreases with increase in % filler,
this could be due to poor interfacial bonding.
Abstract: In recent years a new method of combination
treatment for cancer has been developed and studied that has led to
significant advancements in the field of cancer therapy. Hyperthermia
is a traditional therapy that, along with a creation of a medically
approved level of heat with the help of an alternating magnetic AC
current, results in the destruction of cancer cells by heat. This paper
gives details regarding the production of the spherical nanocomposite
PVA/γ-Fe2O3 in order to be used for medical purposes such as tumor
treatment by hyperthermia. To reach a suitable and evenly distributed
temperature, the nanocomposite with core-shell morphology and
spherical form within a 100 to 200 nanometer size was created using
phase separation emulsion, in which the magnetic nano-particles γ-
Fe2O3 with an average particle size of 20 nano-meters and with
different percentages of 0.2, 0.4, 0.5 and 0.6 were covered by
polyvinyl alcohol. The main concern in hyperthermia and heat
treatment is achieving desirable specific absorption rate (SAR) and
one of the most critical factors in SAR is particle size. In this project
all attempts has been done to reach minimal size and consequently
maximum SAR. The morphological analysis of the spherical
structure of the nanocomposite PVA/γ-Fe2O3 was achieved by SEM
analyses and the study of the chemical bonds created was made
possible by FTIR analysis. To investigate the manner of magnetic
nanocomposite particle size distribution a DLS experiment was
conducted. Moreover, to determine the magnetic behavior of the γ-
Fe2O3 particle and the nanocomposite PVA/γ-Fe2O3 in different
concentrations a VSM test was conducted. To sum up, creating
magnetic nanocomposites with a spherical morphology that would be
employed for drug loading opens doors to new approaches in
developing nanocomposites that provide efficient heat and a
controlled release of drug simultaneously inside the magnetic field,
which are among their positive characteristics that could significantly
improve the recovery process in patients.
Abstract: Tuberculosis (TB) remains a leading cause of
infectious mortality. It is primarily transmitted by the respiratory
route, individuals with active disease may infect others through
airborne particles which releases when they cough, talk, or sing and
subsequently inhale by others. In order to study the effect of the
Bacilli Calmette-Guerin (BCG) vaccine after vaccination of TB
patient, a Vaccinated Susceptible Infected and Recovered (VSIR)
mathematical model is being developed to achieve the desired
objectives. The mathematical model, so developed, shall be used to
quantify the effect of BCG Vaccine to protect the immigrant young
adult person. Moreover, equations are to be established for the
disease endemic and free equilibrium states and subsequently utilized
in disease stability analysis. The stability analysis will give a
complete picture of disease annihilation from the total population if
the total removal rate from the infectious group should be greater
than total number of dormant infections produced throughout
infectious period.
Abstract: In this study, the experiments were carried out to
determine the best coolant for the quenching process among waterbased
silica, alumina, titania and copper oxide nanofluids (0.1 vol%).
A sphere made up off brass material was used in the experiments.
When the spherical test specimen was heated at high temperatures, it
was suddenly immersed into the nanofluids. All experiments were
carried out at saturated conditions and under atmospheric pressure.
After the experiments, the cooling curves were obtained by using the
temperature-time data of the specimen. The experimental results
showed that the cooling performance of test specimen depended on
the type of nanofluids. The silica nanoparticles enhanced the
performance of boiling heat transfer and it is the best coolant for the
quenching among other nanoparticles.
Abstract: Doxorubicin (DOX) is an anthracycline drug used to treat many cancer diseases. Similarly to other cytostatic drugs, DOX has serious side effects; the biggest obstacle is the cardiotoxicity. With the aim of lowering the negative side effects and to target the DOX into the tumor tissue, the different nanoparticles (NPs) are studied. The aim of this work was to synthetized different NPs and conjugated them with DOX and determine the binding capacity of the NPs. For this experiment, carbon nanotubes (CNTs), graphene oxide (GO), fullerene (FUL) and liposomes (LIP) were used. The highest binding capacity was observed in GO (85%). Subsequently the toxicity of NPs and NPs-DOX conjugates was analyzed in in vivo system (chicken embryos). Some NPs (GO) can increase the toxicity of DOX, whereas other NPs (LIP, CNTs) decrease DOX toxicity.
Abstract: Copper (I) oxide microparticles with the morphology
of cubic and hollow sphere were synthesized with the assistance of
surfactant as the shape controller. Both particles were then subjected
to study the catalytic activity and observed the results of shape effects
of catalysts on rate of catalytic reaction. The decolorizing reaction of
crystal violet and sodium hydroxide was chosen and measured the
decreasing of reactant with respect to times using spectrophotometer.
The result revealed that morphology of crystal had no effect on the
catalytic activity for crystal violet reaction but contributed to total
surface area predominantly.
Abstract: Image segmentation and color identification is an
important process used in various emerging fields like intelligent
robotics. A method is proposed for the manipulator to grasp and place
the color object into correct location. The existing methods such as
PSO, has problems like accelerating the convergence speed and
converging to a local minimum leading to sub optimal performance.
To improve the performance, we are using watershed algorithm and
for color identification, we are using EPSO. EPSO method is used to
reduce the probability of being stuck in the local minimum. The
proposed method offers the particles a more powerful global
exploration capability. EPSO methods can determine the particles
stuck in the local minimum and can also enhance learning speed as
the particle movement will be faster.
Abstract: To ensure targeting of apoferritin nanocarrier with
encapsulated doxorubicin drug, we used a peptide linker based on a
protein G with N-terminus affinity towards Fc region of antibodies.
To connect the peptide to the surface of apoferritin, the C-terminus of
peptide was made of cysteine with affinity to gold. The surface of
apoferritin with encapsulated doxorubicin (APODOX) was coated
either with gold nanoparticles (APODOX-Nano) or gold(III) chloride
hydrate reduced with sodium borohydride (APODOX-HAu). The
reduction with sodium borohydride caused a loss of doxorubicin
fluorescent properties and probably accompanied with the loss of its
biological activity. Fluorescent properties of APODOX-Nano were
similar to the unmodified APODOX; therefore it was more suited for
the intended use. To evaluate the specificity of apoferritin modified
with antibodies, ELISA-like method was used with the surface of
microtitration plate wells coated by the antigen (goat anti-human IgG
antibodies). To these wells, the nanocarrier was applied. APODOX
without the modification showed 5× lower affinity to the antigen than
APODOX-Nano modified gold and targeting antibodies (human IgG
antibodies).
Abstract: The novel 3D SnO cabbages self-assembled by
nanosheets were successfully synthesized via template-free
hydrothermal growth method under facile conditions. The XRD
results manifest that the as-prepared SnO is tetragonal phase. The
TEM and HRTEM results show that the cabbage nanosheets are
polycrystalline structure consisted of considerable single-crystalline
nanoparticles. Two typical Raman modes A1g=210 and Eg=112 cm-1
of SnO are observed by Raman spectroscopy. Moreover, galvanostatic
cycling tests has been performed using the SnO cabbages as anode
material of lithium ion battery and the electrochemical results suggest
that the synthesized SnO cabbage structures are a promising anode
material for lithium ion batteries.
Abstract: Development of new generation bio-tribological,
multilayer coatings opens an avenue for fabrication of future hightech
functional surfaces. In the presented work, nano-composite,
Cr/CrN+[Cr/ a-C:H implanted by metallic nanocrystals] multilayer
coatings have been developed for surface protection of medical tools.
Thin films were fabricated by a hybrid Pulsed Laser Deposition
technique. Complex microstructure analysis of nanomultilayer
coatings, subjected to mechanical and biological tests, were
performed by means of transmission electron microscopy (TEM).
Microstructure characterization revealed the layered arrangement of
Cr23C6 nanoparticles in multilayer structure. Influence of deposition
conditions on bio-tribological properties of the coatings was studied.
The bio-tests were used as a screening tool for the analyzed
nanomultilayer coatings before they could be deposited on medical
tools. Bio-medical tests were done using fibroblasts. The mechanical
properties of the coatings were investigated by means of a ball-ondisc
mechanical test. The micro hardness was done using Berkovich
indenter. The scratch adhesion test was done using Rockwell
indenter. From the bio-tribological point of view, the optimal
properties had the C106_1 material.
Abstract: We present a gas-liquid microfluidic system as a
reactor to obtain magnetite nanoparticles with an excellent degree of
control regarding their crystalline phase, shape and size. Several
types of microflow approaches were selected to prevent nanomaterial
aggregation and to promote homogenous size distribution. The
selected reactor consists of a mixer stage aided by ultrasound waves
and a reaction stage using a N2-liquid segmented flow to prevent
magnetite oxidation to non-magnetic phases. A milli-fluidic reactor
was developed to increase the production rate where a magnetite
throughput close to 450 mg/h in a continuous fashion was obtained.
Abstract: Electrodeposition is a simple and economic technique
for precision coating of different shaped substrates with pure metal,
alloy or composite films. Dc electrodeposition was used to produce
Cr, Co-Cr and Co-Cr/TiO2 nano-composite coatings from Cr(III)
based electrolytes onto 316L SS substrates. The effects of TiO2 nanoparticles
concentration on co-deposition of these particles along with
Cr content and microhardness of the coatings were investigated.
Morphology of the Cr, Co-Cr and Co-Cr/TiO2 coatings besides their
tribological behavior were studied. The results showed that increment
of TiO2 nanoparticles concentration from 0 to 30 g L-1 in the bath
increased their co-deposition and Cr content of the coatings from 0 to
3.5 wt.% and from 23.7 to 31.2 wt.%, respectively. Microhardness of
Cr coating was about 920 Hv which was higher than Co-Cr and even
Co-Cr/TiO2 films. Microhardness of Co-Cr and Co-Cr/TiO2 coatings
were improved by increasing their Cr and TiO2 content. All the
coatings had nodular morphology and contained microcracks.
Nodules sizes and the number of microcracks in the alloy and
composite coatings were lower than the Cr film. Wear results
revealed that the Co-Cr/TiO2 coating had the lowest wear loss
between all the samples, while the Cr film had the worst wear
resistance.
Abstract: Heat transfer due to forced convection of copper water
based nanofluid has been predicted by Artificial Neural network
(ANN). The present nanofluid is formed by mixing copper
nanoparticles in water and the volume fractions are considered here
are 0% to 15% and the Reynolds number are kept constant at 100.
The back propagation algorithm is used to train the network. The
present ANN is trained by the input and output data which has been
obtained from the numerical simulation, performed in finite volume
based Computational Fluid Dynamics (CFD) commercial software
Ansys Fluent. The numerical simulation based results are compared
with the back propagation based ANN results. It is found that the
forced convection heat transfer of water based nanofluid can be
predicted correctly by ANN. It is also observed that the back
propagation ANN can predict the heat transfer characteristics of
nanofluid very quickly compared to standard CFD method.
Abstract: Sol-enhanced Zn-Ni-Al2O3 nanocomposite coatings
were electroplated on mild steel by our newly developed solenhanced
electroplating method. In this method, transparent Al2O3 sol
was added into the acidic Zn-Ni bath to produced Zn-Ni-Al2O3nanocomposite
coatings. The chemical composition, microstructure and
mechanical properties of the composite and alloy coatings deposited
at two different agitation speed were investigated. The structure of all
coatings was single γ-Ni5Zn21 phase. The composite coatings possess
refined crystals with higher microhardness compared to Zn-Ni alloy
coatings. The wear resistance of Zn-Ni coatings was improved
significantly by incorporation of alumina nano particles into the
coatings. Higher agitation speed provided more uniform coatings
with smaller grain sized and slightly higher microhardness.
Considering composite coatings, high agitation speeds may facilitate
co-deposition of alumina in the coatings.
Abstract: Chitosan functionalized Fe3O4-Au core shell
nanoparticles have been prepared using a two-step wet chemical
approach using NaBH4 as reducing agent for formation of Au in
ethylene glycol. X-ray diffraction studies shows individual phases of
Fe3O4 and Au in the as prepared samples with crystallite size of 5.9
and 11.4 nm respectively. The functionalization of the core-shell
nanostructure with Chitosan has been confirmed using Fourier
transform infrared spectroscopy along with signatures of octahedral
and tetrahedral sites of Fe3O4 below 600cm-1. Mössbauer
spectroscopy shows decrease in particle-particle interaction in
presence of Au shell (72% sextet) than pure oleic coated Fe3O4
nanoparticles (88% sextet) at room temperature. At 80K, oleic acid
coated Fe3O4 shows only sextets whereas the Chitosan functionalized
Fe3O4 and Chitosan functionalized Fe3O4@Au core shell show
presence of 5 and 11% doublet, respectively.
Abstract: Al6061 alloy base matrix, reinforced with particles of
silicon carbide (10 wt %) and Graphite powder (1wt%), known as
hybrid composites have been fabricated by liquid metallurgy route
(stir casting technique) and optimized at different parameters like
applied load, sliding speed and sliding distance by taguchi method. A
plan of experiment generated through taguchi technique was used to
perform experiments based on L27 orthogonal array. The developed
ANOVA and regression equations are used to find the optimum
coefficient of friction and wear under the influence of applied load,
sliding speed and sliding distance. On the basis of “smaller the best”
the dry sliding wear resistance was analysed and finally confirmation
tests were carried out to verify the experimental results.
Abstract: A comprehensive CFD model is developed to
represent heterogeneous combustion and two burner designs of
supply sugar-cane bagasse into a furnace. The objective of this work
is to compare the insertion and burning of a Brazilian south-eastern
sugar-cane bagasse using a new swirl burner design against an actual
geometry under operation. The new design allows control the
particles penetration and scattering inside furnace by adjustment of
axial/tangential contributions of air feed without change their mass
flow. The model considers turbulence using RNG k-, combustion
using EDM, radiation heat transfer using DTM with 16 ray directions
and bagasse particle tracking represented by Schiller-Naumann
model. The obtained results are favorable to use of new design swirl
burner because its axial/tangential control promotes more penetration
or more scattering than actual design and allows reproduce the actual
design operation without change the overall mass flow supply.
Abstract: The use of engineered nanomaterials has increased as
a result of their positive impact on many sectors of the economy,
including agriculture. Silver nanoparticles (AgNPs) are now used to
enhance seed germination, plant growth, and photosynthetic quantum
efficiency and as antimicrobial agents to control plant diseases. In
this study, we examined the effect of AgNP dosage on the seed
germination of three plant species: corn (Zea mays L.), watermelon
(Citrullus lanatus [Thunb.] Matsum. & Nakai) and zucchini
(Cucurbita pepo L.). This experiment was designed to study the
effect of AgNPs on germination percentage, germination rate, mean
germination time, root length and fresh and dry weight of seedlings
for the three species. Seven concentrations (0.05, 0.1, 0.5, 1, 1.5, 2
and 2.5 mg/ml) of AgNPs were examined at the seed germination
stage. The three species had different dose responses to AgNPs in
terms of germination parameters and the measured growth
characteristics. The germination rates of the three plants were
enhanced in response to AgNPs. Significant enhancement of the
germination percentage values was observed after treatment of the
watermelon and zucchini plants with AgNPs in comparison with
untreated seeds. AgNPs showed a toxic effect on corn root
elongation, whereas watermelon and zucchini seedling growth were
positively affected by certain concentrations of AgNPs. This study
showed that exposure to AgNPs caused both positive and negative
effects on plant growth and germination.
Abstract: One of the main challenges in using the Discrete
Element Method (DEM) is to specify the correct input parameter
values. In general, the models are sensitive to the input parameter
values and accurate results can only be achieved if the correct values
are specified. For the linear contact model, micro-parameters such as
the particle density, stiffness, coefficient of friction, as well as the
particle size and shape distributions are required. There is a need for
a procedure to accurately calibrate these parameters before any
attempt can be made to accurately model a complete bulk materials
handling system. Since DEM is often used to model applications in
the mining and quarrying industries, a calibration procedure was
developed for materials that consist of relatively large (up to 40 mm
in size) particles. A coarse crushed aggregate was used as the test
material. Using a specially designed large shear box with a diameter
of 590 mm, the confined Young’s modulus (bulk stiffness) and
internal friction angle of the material were measured by means of the
confined compression test and the direct shear test respectively. DEM
models of the experimental setup were developed and the input
parameter values were varied iteratively until a close correlation
between the experimental and numerical results was achieved. The
calibration process was validated by modelling the pull-out of an
anchor from a bed of material. The model results compared well with
experimental measurement.
Abstract: High pressure turbine (HPT) blades of DV – 2 jet
engines are made from Ni – based superalloy. This alloy was
originally manufactured in the Soviet Union and referred as ŽS6K.
For improving alloy’s high temperature resistance are blades coated
with Al – Si diffusion layer. A regular operation temperature of HPT
blades vary from 705°C to 750°C depending on jet engine regime.
An overcrossing working temperature range causes degradation of
the protective coating as well as base material which microstructure
is formed by the gamma matrix and strengthening phase gamma
prime (forming small particles in the microstructure). Diffusion
processes inside the material during exposition of the material to high
temperatures causes mainly coarsening of the gamma prime particles,
thus decreasing its strengthening effect. Degradation of the Al – Si
coating caused its thickness growth. All the microstructure changes
and coating layer thickness growth results in decreasing of the turbine
blade operation lifetime.