Abstract: Polymerase chain reaction (PCR) assay and
conventional microbiological methods were used to detect bacterial
contamination of egg shells and egg content in different commercial
housing systems, open house system and evaporative cooling system.
A PCR assay was developed for direct detection using a set of
primers specific for the invasion by A gene (invA) of Salmonella spp.
PCR detected the presence of Salmonella in 2 samples of shell egg
from the evaporative cooling system, while conventional cultural
methods detected no Salmonella from the same samples.
Abstract: In the present work, study of the vibration of thin cylindrical shells made of a functionally gradient material (FGM) composed of stainless steel and nickel is presented. Material properties are graded in the thickness direction of the shell according to volume fraction power law distribution. The objective is to study the natural frequencies, the influence of constituent volume fractions and the effects of boundary conditions on the natural frequencies of the FG cylindrical shell. The study is carried out using third order shear deformation shell theory. The analysis is carried out using Hamilton's principle. The governing equations of motion of FG cylindrical shells are derived based on shear deformation theory. Results are presented on the frequency characteristics, influence of constituent volume fractions and the effects of free-free and clamped-clamped boundary conditions.
Abstract: In this article, biomechanical aspects of hen-s eggshell as a natural ceramic structure are studied. The images, taken by a scanning electron microscope (SEM), are used to investigate the microscopic aspects of the egg. It is observed that eggshell has a three-layered microstructure with different morphological and structural characteristics. Studies on the eggshell membrane (ESM) as a prosperous tissue suggest that it is placed to prevent the penetration of microorganisms into the egg. Finally, numerical models of the egg are presented to study the stress distribution and its deformation under different loading conditions. The effects of two different types of loading (hydrostatic and point loadings) on two different shell models (with constant and variable thicknesses) are investigated in detail.
Abstract: In order to obtaining the dynamic evolution image of Tungsten array for foam padding, and to research the form of interaction between Tungsten plasma and foam column, a shadow imaging system of four-frame ultraviolet probe laser (266nm)has been designed on 1MA pulse power device. The time resolution of the system is 2.5ns, and static space resolution is superior to 70μm. The radial shadowgraphy image reveals the whole process from the melting and expansion of solid wire to the interaction of the precursor plasma and the foam, from the pinch to rebound inflation. The image shows the continuous interaction of Tungsten plasma and foam in a form of “Raining" within a time of about 50ns, the plasma shell structure has not been found in the whole period of pinch. The quantitative analysis indicates the minimum pinching speed of the foam column is 1.0×106cm/s, and maximum pinching speed is 6.0×106cm/s, and the axial stagnation diameter is approx 1mm.
Abstract: Study of fire and explosion is very important mainly
in oil and gas industries due to several accidents which have been
reported in the past and present. In this work, we have investigated
the flammability of bio oil vapour mixtures. This mixture may
contribute to fire during the storage and transportation process. Bio
oil sample derived from Palm Kernell shell was analysed using Gas
Chromatography Mass Spectrometry (GC-MS) to examine the
composition of the sample. Mole fractions of 12 selected
components in the liquid phase were obtained from the GC-FID data
and used to calculate mole fractions of components in the gas phase
via modified Raoult-s law. Lower Flammability Limits (LFLs) and
Upper Flammability Limits (UFLs) for individual components were
obtained from published literature. However, stoichiometric
concentration method was used to calculate the flammability limits
of some components which their flammability limit values are not
available in the literature. The LFL and UFL values for the mixture
were calculated using the Le Chatelier equation. The LFLmix and
UFLmix values were used to construct a flammability diagram and
subsequently used to determine the flammability of the mixture. The
findings of this study can be used to propose suitable inherently
safer method to prevent the flammable mixture from occurring and
to minimizing the loss of properties, business, and life due to fire
accidents in bio oil productions.
Abstract: The storage of thermal energy as a latent heat of phase
change material (PCM) has created considerable interest among
researchers in recent times. Here, an attempt is made to carry out
numerical investigations to analyze the performance of latent heat
storage units (LHSU) employing phase change material. The
mathematical model developed is based on an enthalpy formulation.
Freezing time of PCM packed in three different shaped containers
viz. rectangular, cylindrical and cylindrical shell is compared. The
model is validated with the results available in the literature. Results
show that for the same mass of PCM and surface area of heat
transfer, cylindrical shell container takes the least time for freezing
the PCM and this geometric effect is more pronounced with an
increase in the thickness of the shell than that of length of the shell.
Abstract: The heat storage capacity of concrete in building shells is a major reason for excessively large electricity consumption induced by indoor air conditioning. In this research, the previously developed Smart Temperature Information Material (STIM) is embedded in two groups of exterior wall specimens (the control group contains reinforced concrete exterior walls and the experimental group consists of tiled exterior walls). Long term temperature measurements within the concrete are taken by the embedded STIM. Temperature differences between the control group and the experimental group in walls facing the four cardinal directions (east, west, south, and north) are evaluated. This study aims to provide a basic reference for the design of exterior walls and the selection of heat insulation materials.
Abstract: Thermal conductivity is an important characteristic of
a nanofluid in laminar flow heat transfer. This paper presents an
improved model for the prediction of the effective thermal
conductivity of nanofluids based on dimensionless groups. The
model expresses the thermal conductivity of a nanofluid as a function
of the thermal conductivity of the solid and liquid, their volume
fractions and particle size. The proposed model includes a parameter
which accounts for the interfacial shell, brownian motion, and
aggregation of particle. The validation of the model is verified by
applying the results obtained by the experiments of Tio2-water and
Al2o3-water nanofluids.
Abstract: Activated carbon was prepared from agricultural waste “almond (Prunus amygdalus) nut shells" by chemical activation with phosphoric acid as an activating agent at 450 °C for 24 hr soaking time. The physical and chemical properties were analyzed. The adsorption of chromium VI from aqueous solution on almond nut shell activated carbon (ASAC) was investigated. The adsorption process parameters pH, agitation speed, agitation time, adsorbent dose were optimized. 98% of Cr VI was sorbed at pH 2 and stirring speed 200 rpm.. Surface structure showed that ASAC has a spongy type structure showing large number of pores
Abstract: This work presents the hydrogen production from
steam gasification of palm kernel shell (PKS) at 700 oC in the
presence of 5% Ni/BEA and 5% Fe/BEA as catalysts. The steam
gasification was performed in two-staged reactors to evaluate the
effect of calcinations temperature and the steam to biomass ratio on
the product gas composition. The catalytic activity of Ni/BEA
catalyst decreases with increasing calcinations temperatures from 500
to 700 oC. The highest H2 concentration is produced by Fe/BEA
(600) with more than 71 vol%. The catalytic activity of the catalysts
tested is found to correspond to its physicochemical properties. The
optimum range for steam to biomass ratio if found to be between 2 to
4. Excess steam content results in temperature drop in the gasifier
which is undesirable for the gasification reactions.
Abstract: The pyrolysis of hazelnut shell, polyethylene oxide and their blends were carried out catalytically at 500 and 650 ºC. Potassium dichromate was chosen according to its oxidative characteristics and decomposition temperature (500 ºC) where decomposition products are CrO3 and K2CrO4. As a main effect, a remarkable increase in gasification was observed using this catalyst for pure components and blends especially at 500 ºC rather than 650 ºC contrary to the main observation in the pyrolysis process. The increase in gas product quantity was compensated mainly with decrease in solid product and additionally in some cases liquid products.
Abstract: The static stability analysis of stiffened functionally
graded cylindrical shells by isotropic rings and stringers subjected to
axial compression is presented in this paper. The Young's modulus of
the shell is taken to be function of the thickness coordinate. The
fundamental relations, the equilibrium and stability equations are
derived using the Sander's assumption. Resulting equations are
employed to obtain the closed-form solution for the critical axial
loads. The effects of material properties, geometric size and different
material coefficient on the critical axial loads are examined. The
analytical results are compared and validated using the finite element
model.
Abstract: This paper reports on the enhanced photoluminescence
(PL) of nanocomposites through the layered structuring of phosphor
and quantum dot (QD). Green phosphor of Sr2SiO4:Eu, red QDs of
CdSe/CdS/CdZnS/ZnS core-multishell, and thermo-curable resin
were used for this study. Two kinds of composite (layered and mixed)
were prepared, and the schemes for optical energy transfer between
QD and phosphor were suggested and investigated based on PL decay
characteristics. It was found that the layered structure is more effective
than the mixed one in the respects of PL intensity, PL decay and
thermal loss. When this layered nanocomposite (QDs on phosphor) is
used to make white light emitting diode (LED), the brightness is
increased by 37 %, and the color rendering index (CRI) value is raised
to 88.4 compared to the mixed case of 80.4.
Abstract: This paper aims to study decomposition behavior in
pyrolytic environment of four lignocellulosic biomass (oil palm shell,
oil palm frond, rice husk and paddy straw), and two commercial
components of biomass (pure cellulose and lignin), performed in a
thermogravimetry analyzer (TGA). The unit which consists of a
microbalance and a furnace flowed with 100 cc (STP) min-1 Nitrogen,
N2 as inert. Heating rate was set at 20⁰C min-1 and temperature
started from 50 to 900⁰C. Hydrogen gas production during the
pyrolysis was observed using Agilent Gas Chromatography Analyzer
7890A. Oil palm shell, oil palm frond, paddy straw and rice husk
were found to be reactive enough in a pyrolytic environment of up to
900°C since pyrolysis of these biomass starts at temperature as low as
200°C and maximum value of weight loss is achieved at about
500°C. Since there was not much different in the cellulose,
hemicelluloses and lignin fractions between oil palm shell, oil palm
frond, paddy straw and rice husk, the T-50 and R-50 values obtained
are almost similar. H2 productions started rapidly at this temperature
as well due to the decompositions of biomass inside the TGA.
Biomass with more lignin content such as oil palm shell was found to
have longer duration of H2 production compared to materials of high
cellulose and hemicelluloses contents.
Abstract: This paper deals with the status of solid waste pollution in touristic spots of North coastal Andhra Pradesh. Case studies of Eco tourism, cultural tourism and pilgrim tourism are elaborately discussed and the study is based on both primary and secondary data. Data collection includes field collection of solid waste, semi structured interviews and observation of tourists. Results indicate generation of 72% Non biodegradable material in Eco touristic places like RK beach Visakhapatnam, Araku Valley. Pydithalli Jathra is a famous cultural touristic attraction and more than one lakh people converge here. The solid waste at this spot includes 20% coconut shells, 50% plastic bottles and covers, 20% Banana peelings and remaining are food materials. Radhasapthami is the most important festival celebrated at famous sun temple Arasavalli of Srikakulam. Here solid waste includes 50% water bottles, plastic covers, 10% papers, 10% hair, 30% left out food material and Banana peelings.
Abstract: As the fossil fuels kept on depleting, intense research in developing hydrogen (H2) as the alternative fuel has been done to cater our tremendous demand for fuel. The potential of H2 as the ultimate clean fuel differs with the fossil fuel that releases significant amounts of carbon dioxide (CO2) into the surrounding and leads to the global warming. The experimental work was carried out to study the production of H2 from palm kernel shell steam gasification at different variables such as heating rate, steam to biomass ratio and adsorbent to biomass ratio. Maximum H2 composition which is 61% (volume basis) was obtained at heating rate of 100oCmin-1, steam/biomass of 2:1 ratio, and adsorbent/biomass of 1:1 ratio. The commercial adsorbent had been modified by utilizing the alcoholwater mixture. Characteristics of both adsorbents were investigated and it is concluded that flowability and floodability of modified CaO is significantly improved.
Abstract: In this study the mixed convection heat transfer in a
coil-in-shell heat exchanger for various Reynolds numbers and
various dimensionless coil pitch was experimentally investigated.
The experiments were conducted for both laminar and turbulent flow
inside coil and the effects of coil pitch on shell-side heat transfer
coefficient of the heat exchanger were studied. The particular
difference in this study in comparison with the other similar studies
was the boundary conditions for the helical coils. The results indicate
that with the increase of coil pitch, shell-side heat transfer coefficient
is increased.
Abstract: The objective of the research is to study and compare
response surface designs: Central composite designs (CCD), Box-
Behnken designs (BBD), Small composite designs (SCD), Hybrid
designs, and Uniform shell designs (USD) over sets of reduced models
when the design is in a spherical region for 3 and 4 design variables.
The two optimality criteria ( D and G ) are considered which larger
values imply a better design. The comparison of design optimality
criteria of the response surface designs across the full second order
model and sets of reduced models for 3 and 4 factors based on the
two criteria are presented.
Abstract: We have developed an analytic model for the radial pn-junction in a nanowire (NW) core-shell structure utilizing as a new
building block in different semiconductor devices. The potential distribution through the p-n-junction is calculated and the analytical expressions are derived to compute the depletion region widths. We
show that the widths of space charge layers, surrounding the core, are
the functions of core radius, which is the manifestation of so called classical size effect. The relationship between the depletion layer width and the built-in potential in the asymptotes of infinitely large
core radius transforms to square-root dependence specific for conventional planar p-n-junctions. The explicit equation is derived to
compute the capacitance of radial p-n-junction. The current-voltage behavior is also carefully determined taking into account the “short
base" effects.
Abstract: Customarily, the LMTD correction factor, FT, is used
to screen alternative designs for a heat exchanger. Designs with
unacceptably low FT values are discarded. In this paper, authors have
proposed a more fundamental criterion, based on feasibility of a
multipass exchanger as the only criteria, followed by economic
optimization. This criterion, coupled with asymptotic energy targets,
provide the complete optimization space in a heat exchanger network
(HEN), where cost-optimization of HEN can be performed with only
Heat Recovery Approach temperature (HRAT) and number-of-shells
as variables.