Abstract: The objective of this research is to mitigate and prevent
the alkali silica reactivity (ASR) in highway construction projects.
ASR is a deleterious reaction initiated when the silica content of the
aggregate reacts with alkali hydroxides in cement in the presence of
relatively high moisture content. The ASR results in the formation of
an expansive white colored gel-like material which forms the
destructive tensile stresses inside hardened concrete. In this research, different types of local aggregates available in the
State of Arkansas were mixed and mortar bars were poured according
to the ASTM specifications. Mortar bars expansion was measured
versus time and aggregates with potential ASR problems were
detected. Different types of supplementary cementitious materials
(SCMs) were used in remixing mortar bars with highly reactive
aggregates. Length changes for remixed bars proved that different
types of SCMs can be successfully used in reducing the expansive
effect of ASR. SCMs percentage by weight is highly dependent on
the SCM type. The result of this study will help avoiding future
losses due to ASR cracking in construction project and reduce the
maintenance, repair, and replacement budgets required for highways
network.
Abstract: Microstructure and fabric of soils play an important
role on structural properties e.g. stiffness and strength of compacted
earthwork. Traditional quality control monitoring based on moisturedensity
tests neither reflects the variability of soil microstructure nor
provides a direct assessment of structural property, which is the
ultimate objective of the earthwork quality control. Since stiffness
and strength are sensitive to soil microstructure and fabric, any
independent test methods that provide simple, rapid, and direct
measurement of stiffness and strength are anticipated to provide an
effective assessment of compacted earthen materials’ uniformity. In
this study, the soil stiffness gauge (SSG) and the dynamic cone
penetrometer (DCP) were respectively utilized to measure and
monitor the stiffness and strength in companion with traditional
moisture-density measurements of various earthen materials used in
Thailand road construction projects. The practical earthwork quality
control criteria are presented herein in order to assure proper
earthwork quality control and uniform structural property of
compacted earthworks.
Abstract: With the strengthened regulation on the mandatory use
of recycled aggregate, development of construction materials using
recycled aggregate has recently increased. This study aimed to secure
the performance of asphalt concrete mixture by developing
recycled-modified asphalt using recycled basalt aggregate from the
Jeju area. The strength of the basalt aggregate from the Jeju area used
in this study was similar to that of general aggregate, while the specific
surface area was larger due to the development of pores. Modified
asphalt was developed using a general aggregate-recycled aggregate
ratio of 7:3, and the results indicated that the Marshall stability
increased by 27% compared to that of asphalt concrete mixture using
only general aggregate, and the flow values showed similar levels.
Also, the indirect tensile strength increased by 79%, and the toughness
increased by more than 100%. In addition, the TSR for examining
moisture resistance was 0.95 indicating that the reduction in the
indirect tensile strength due to moisture was very low (5% level), and
the developed recycled-modified asphalt could satisfy all the quality
standards of asphalt concrete mixture.
Abstract: Medicinal and aromatic plants are promising and are characterized by the biosynthesis of odorous molecules that make up the so-called essential oils (EO), which have long been known for their antiseptic and therapeutic activity in folk medicine. Essential oils have many therapeutic properties. In herbal medicine, they are used for their antiseptic properties against infectious diseases of fungal origin, against dermatophytes, those of bacterial origin. The objective of this study was to evaluate the influence of drying in the shade on the water content and on the content of essential oils extracted from leaves of Eucalyptus camendulensis for better quality control of medicinal and aromatic plants. The water content of the Eucalyptus camendulensis plant material decreases during the drying process. It decreased from 100% to 0.006% for the drying in the shade after ten days. The moisture content is practically constant at the end of the drying period. The drying in the shade increases the concentration of essential oils of Eucalyptus camendulensis. When the leaves of Eucalyptus camendulensis plant are in the shade, the maximum of the essential oil content was obtained on the eighth day, the recorded value was 1.43% ± 0.01%. Beyond these periods, the content continuously drop in before stabilizing. The optimum drying time is between 6 and 9 days.
Abstract: There was a scenario present day that drying of fresh
fruits and vegetables by indirect solar drying by using mechanical
device; hence, an effort was made to develop a small scale solar
tunnel dryer (STD). Drying of spinach is carried out to analyze the
performance of the dryer and to study its drying characteristics. To
evaluate the performance of dryer the independent variables were
selected as air flow rate, loading density and shade net while collector
efficiency, drying efficiency, overall efficiency and specific energy
consumption were selected as responses during performing the
experiments. The spinach was dried from initial moisture content
88.21-94.04% (w.b.) to final moisture content 3.50-5.13% (w.b.). The
drying time considerably reduced as compared to open sun drying of
spinach as sun drying took 15 h for drying. The average collector
efficiency, drying efficiency and overall efficiency were in the range
28.73-61.15%, 11.63% to 22.13%, and 7.61-14.66%, respectively.
Abstract: The post-rain puddles problem that occurs in the first
yard of Prambanan Temple are often disturbing visitor activity. A
poodle layer and a drainage system had ever built to avoid such a
problem, but puddles still did not stop appearing after rain.
Permeability parameter needs to be determined by using a simpler
procedure to find exact method of solution. The instrument modelling
was proposed according to the development of field permeability
testing instrument. This experiment used a proposed Constant
Discharge method. Constant Discharge method used a tube poured
with constant water flow from unsaturated until saturated soil
condition. Volumetric water content (θ) were monitored by soil
moisture measurement device. The results were correlations between
k and θ which were drawn by numerical approach from Van
Genutchen model. Parameters θr optimum value obtained from the
test was at very dry soil. Coefficient of permeability with a density of
19.8 kN/m3 for unsaturated conditions was in range of 3 x 10-6
cm/sec (Sr=68%) until 9.98 x 10-4 cm/sec (Sr=82%). The equipment
and testing procedure developed in this research was quite effective,
simple and easy to be implemented on determining field soil
permeability coefficient value of sandy soil. Using constant discharge
method in proposed permeability test, value of permeability
coefficient under unsaturated condition can be obtained without
establish soil water characteristic curve.
Abstract: A clay soil classified as A-7-6 and CH soil according
to AASHTO and unified soil classification system respectively, was
stabilized using A-3 soil (AASHTO soil classification system). The
clay soil was replaced with 0%, 10%, 20%, to 100% A-3 soil,
compacted at both British Standard Light (BSL) and British Standard
Heavy (BSH) compaction energy levels and using Unconfined
Compressive Strength (UCS) as evaluation criteria. The Maximum
Dry Density (MDD) of the treated soils at both the BSL and BSH
compaction energy levels showed increase from 0% to 40% A-3 soil
replacement after which the values reduced to 100% replacement.
The trend of the Optimum Moisture Content (OMC) with varied A-3
soil replacement was similar to that of MDD but in a reversed order.
The OMC reduced from 0% to 40% A-3 soil replacement after which
the values increased to 100% replacement. This trend was attributed
to the observed reduction in void ratio from 0% to 40% replacement
after which the void ratio increased to 100% replacement. The
maximum UCS for the soil at varied A-3 soil replacement increased
from 272 and 770 kN/m2 for BSL and BSH compaction energy level
at 0% replacement to 295 and 795 kN/m2 for BSL and BSH
compaction energy level respectively at 10% replacement after which
the values reduced to 22 and 60 kN/m2 for BSL and BSH compaction
energy level respectively at 70% replacement. Beyond 70%
replacement, the mixtures could not be moulded for UCS test.
Abstract: The need to save time and cost of soil testing at the
planning stage of road work has necessitated developing predictive
models. This study proposes a model for predicting the dry density of
lateritic soils stabilized with corn cob ash (CCA) and blended cement
- CCA. Lateritic soil was first stabilized with CCA at 1.5, 3.0, 4.5 and
6% of the weight of soil and then stabilized with the same
proportions as replacement for cement. Dry density, specific gravity,
maximum degree of saturation and moisture content were determined
for each stabilized soil specimen, following standard procedure.
Polynomial equations containing alpha and beta parameters for CCA
and blended CCA-cement were developed. Experimental values were
correlated with the values predicted from the Matlab curve fitting
tool, and the Solver function of Microsoft Excel 2010. The correlation
coefficient (R2) of 0.86 was obtained indicating that the model could
be accepted in predicting the maximum dry density of CCA stabilized
soils to facilitate quick decision making in roadworks.
Abstract: The advancements in technology allow the
development of a new system that can continuously measure surface
soil erosion. Continuous soil erosion measurements are required in
order to comprehend the erosional processes and propose effective
and efficient conservation measures to mitigate surface erosion.
Mitigating soil erosion, especially in Mediterranean countries such as
Greece, is essential in order to maintain environmental and
agricultural sustainability. In this paper, we present the Automated
Soil Erosion Monitoring System (ASEMS) that measures surface soil
erosion along with other factors that impact erosional process.
Specifically, this system measures ground level changes (surface soil
erosion), rainfall, air temperature, soil temperature, and soil moisture.
Another important innovation is that the data will be collected by
remote communication. In addition, stakeholder’s awareness is a key
factor to help reduce any environmental problem. The different
dissemination activities that were utilized are described. The overall
outcomes were the development of a new innovative system that can
measure erosion very accurately. These data from the system help
study the process of erosion and find the best possible methods to
reduce erosion. The dissemination activities enhance the stakeholders
and public's awareness on surface soil erosion problems and will lead
to the adoption of more effective soil erosion conservation practices
in Greece.
Abstract: The development of composite materials and the
related design and manufacturing technologies is one of the most
important advances in the history of materials. Composites are
multifunctional materials having unprecedented mechanical and
physical properties that can be tailored to meet the requirements of a
particular application. Some composites also exhibit great resistance
to high-temperature corrosion, oxidation, and wear. Polymers are
widely used indoors and outdoors, therefore they are exposed to a
chemical environment which may include atmospheric oxygen, acidic
fumes, acidic rain, moisture heat and thermal shock, ultra-violet light,
high energy radiation, etc. Different polymers are affected differently
by these factors even though the amorphous polymers are more
sensitive. Ageing is also important and it is defined as the process of
deterioration of engineering materials resulting from the combined
effects of atmospheric radiation, heat, oxygen, water, microorganisms
and other atmospheric factors.
Abstract: The effects of wood ash from five common tropical
woods on the ignition point of four common tropical woods in
Nigeria were investigated. The ash and moisture contents of the wood
sawdust from Mahogany (Khaya ivorensis), Opepe (Sarcocephalus
latifolius), Abura (Mitragyna ciliata), Rubber (Heavea brasilensis)
and Poroporo (Sorghum bicolour) used, were determined using a
furnace (Vecstar furnaces, model ECF2, serial no. f3077) and oven
(Genlab laboratory oven, model MINO/040) respectively. The metal
contents of the five wood sawdust ash samples were determined
using a Perkin Elmer optima 3000 dv atomic absorption spectrometer
while the ignition points were determined using Vecstar furnaces
model ECF2. Poroporo had the highest ash content, 2.263g while
rubber had the least, 0.710g. The results for the moisture content
range from 2.971g to 0.903g. Magnesium metal had the highest
concentration of all the metals, in all the wood ash samples; with
mahogany ash having the highest concentration, 9.196ppm while
rubber ash had the least concentration of magnesium metal, 2.196
ppm. The ignition point results showed that the wood ashes from
mahogany and opepe increased the ignition points of the test wood
samples, Danta (Nesogordonia papaverifera), Ekpaya, Akomu
(Pycnanthus angolensis) and Oleku when coated on them while the
ashes from poroporo, rubber and abura decreased the ignition points
of the test wood samples when coated on them. However, Opepe saw
dust ash decreased the ignition point in one of the test wood samples,
suggesting that the metal content of the test wood sample was more
than that of the Opepe saw dust ash. Therefore, Mahogany and Opepe
saw dust ashes could be used in the surface treatment of wood to
enhance their fire resistance or retardancy. However, the caution to
be exercised in this application is that the metal content of the test
wood samples should be evaluated as well.
Abstract: Lyophilization, also called freeze-drying, is an
important dehydration technique mainly used for pharmaceuticals.
Food industry also uses lyophilization when it is important to retain
most of the nutritional quality, taste, shape and size of dried products
and to extend their shelf life. Vacuum-Induced during freezing cycle
(VI) has been used in order to control ice nucleation and,
consequently, to reduce the time of primary drying cycle of
pharmaceuticals preserving quality properties of the final product.
This procedure has not been applied in freeze drying of foods. The
present work aims to investigate the effect of VI on the lyophilization
drying time, final moisture content, density and reconstitutional
properties of mango (Mangifera indica L.) slices (MS) and mango
pulp-maltodextrin dispersions (MPM) (30% concentration of total
solids). Control samples were run at each freezing rate without using
induced vacuum. The lyophilization endpoint was the same for all
treatments (constant difference between capacitance and Pirani
vacuum gauges). From the experimental results it can be concluded
that at the high freezing rate (0.4°C/min) reduced the overall process
time up to 30% comparing process time required for the control and
VI of the lower freeze rate (0.1°C/min) without affecting the quality
characteristics of the dried product, which yields a reduction in costs
and energy consumption for MS and MPM freeze drying. Controls
and samples treated with VI at freezing rate of 0.4°C/min in MS
showed similar results in moisture and density parameters.
Furthermore, results from MPM dispersion showed favorable values
when VI was applied because dried product with low moisture
content and low density was obtained at shorter process time
compared with the control. There were not found significant
differences between reconstitutional properties (rehydration for MS
and solubility for MPM) of freeze dried mango resulting from
controls, and VI treatments.
Abstract: High moisture content in fruits generates post-harvest
problems such as mechanical, biochemical, microbial and physical
losses. Dehydration, which is based on the reduction of water activity
of the fruit, is a common option for overcoming such losses.
However, regular hot air drying could affect negatively the quality
properties of the fruit due to the long residence time at high
temperature. Power ultrasound (US) application during the
convective drying has been used as a novel method able to enhance
drying rate and, consequently, to decrease drying time. In the present
study, a new approach was tested to evaluate the effect of US on the
drying time, the final antioxidant activity (AA) and the total
polyphenol content (TPC) of banana slices (BS), mango slices (MS)
and guava slices (GS). There were also studied the drying kinetics
with nine different models from which water effective diffusivities
(Deff) (with or without shrinkage corrections) were calculated.
Compared with the corresponding control tests, US assisted drying
for fruit slices showed reductions in drying time between 16.23 and
30.19%, 11.34 and 32.73%, and 19.25 and 47.51% for the MS, BS
and GS respectively. Considering shrinkage effects, Deff calculated
values ranged from 1.67*10-10 to 3.18*10-10 m2/s, 3.96*10-10 and
5.57*10-10 m2/s and 4.61*10-10 to 8.16*10-10 m2/s for the BS, MS and
GS samples respectively. Reductions of TPC and AA (as DPPH)
were observed compared with the original content in fresh fruit data
in all kinds of drying assays.
Abstract: Comparative analysis of the properties of melon seed,
coconut fruit and their oil yield were evaluated in this work using
standard analytical technique AOAC. The results of the analysis
carried out revealed that the moisture contents of the samples studied
are 11.15% (melon) and 7.59% (coconut). The crude lipid content are
46.10% (melon) and 55.15% (coconut).The treatment combinations
used (leaching time, leaching temperature and solute: solvent ratio)
showed significant difference (p < 0.05) in yield between the
samples, with melon oil seed flour having a higher percentage range
of oil yield (41.30 – 52.90%) and coconut (36.25 – 49.83%). The
physical characterization of the extracted oil was also carried out.
The values gotten for refractive index are 1.487 (melon seed oil) and
1.361 (coconut oil) and viscosities are 0.008 (melon seed oil) and
0.002 (coconut oil). The chemical analysis of the extracted oils shows
acid value of 1.00mg NaOH/g oil (melon oil), 10.050mg NaOH/g oil
(coconut oil) and saponification value of 187.00mg/KOH (melon oil)
and 183.26mg/KOH (coconut oil). The iodine value of the melon oil
gave 75.00mg I2/g and 81.00mg I2/g for coconut oil. A standard
statistical package Minitab version 16.0 was used in the regression
analysis and analysis of variance (ANOVA). The statistical software
mentioned above was also used to optimize the leaching process.
Both samples gave high oil yield at the same optimal conditions. The
optimal conditions to obtain highest oil yield ≥ 52% (melon seed)
and ≥ 48% (coconut seed) are solute - solvent ratio of 40g/ml,
leaching time of 2hours and leaching temperature of 50oC. The two
samples studied have potential of yielding oil with melon seed giving
the higher yield.
Abstract: The purpose of the present work was to develop an innovative food product with good textural and sensorial characteristics. The product, a new type of bread, was prepared with wheat (90%) and lupin (10%) flours, without the addition of any conservatives. Several experiences were also done to find the most appropriate proportion of lupin flour. The optimized product was characterized considering the rheological, physical-chemical and sensorial properties. The water absorption of wheat flour with 10% of lupin was higher than that of the normal wheat flours, and Wheat Ceres flour presented the lower value, with lower dough development time and high stability time. The breads presented low moisture but a considerable water activity. The density of bread decreased with the introduction of lupin flour. The breads were quite white, and during storage the colour parameters decreased. The lupin flour clearly increased the number of alveolus, but the total area increased significantly just for the Wheat Cerealis bread. The addition of lupin flour increased the hardness and chewiness of breads, but the elasticity did not vary significantly. Lupin bread was sensorially similar to wheat bread produced with WCerealis flour, and the main differences are the crust rugosity, colour and alveolus characteristics.
Abstract: The main idea of this work is to investigate the effect
of knitted fabrics characteristics on moisture management properties.
Wetting and transport properties of single jersey, Rib 1&1 and
English Rib fabrics made out of cotton and blended Cotton/Polyester
yarns were studied. The dynamic water sorption of fabrics was
investigated under same isothermal and terrestrial conditions at
20±2°C-65±4% by using the Moisture Management Tester (MMT)
which can be used to quantitatively measure liquid moisture transfer
in one step in a fabric in multidirections: Absorption rate, moisture
absorbing time of the fabric's inner and outer surfaces, one-way
transportation capability, the spreading/drying rate, the speed of
liquid moisture spreading on fabric's inner and outer surfaces are
measured, recorded and discussed. The results show that fabric’s
composition and knit’s structure have a significant influence on those
phenomena.
Abstract: The moisture content of densified biomass is a
limiting parameter influencing the quality of this solid biofuel. It
influences its calorific value, density, mechanical strength and
dimensional stability as well as affecting its production process. This
paper deals with experimental research into the effect of moisture
content of the densified material on the final quality of biofuel in the
form of logs (briquettes or pellets). Experiments based on the singleaxis
densification of the spruce sawdust were carried out with a
hydraulic piston press (piston and die), where the densified logs were
produced at room temperature. The effect of moisture content on the
qualitative properties of the logs, including density, change of
moisture, expansion and physical changes, and compressive and
impact resistance were studied. The results show the moisture ranges
required for producing good-quality logs. The experiments were
evaluated and the moisture content of the tested material was
optimized to achieve the optimum value for the best quality of the
solid biofuel. The dense logs also have high-energy content per unit
volume. The research results could be used to develop and optimize
industrial technologies and machinery for biomass densification to
achieve high quality solid biofuel.
Abstract: This study intends to show the influence of the
hydrolytic degradation on the properties of the e-PTFE/NOMEX®
membranes used in fire-protective clothing. The modification of
water vapour permeability, morphology and chemical structure was
examined by MOCON Permatran, electron microscopy scanning
(SEM), and ATR-FTIR, respectively. A decrease in permeability to
water vapour of the aged samples was observed following closure of
transpiration pores. Analysis of fiber morphology indicates the
appearance of defects at the fibers surface with the presence of micro
cavities. ATR-FTIR analysis reveals the presence of a new absorption
band attributed to carboxylic acid terminal groups generated during
the amide bond hydrolysis.
Abstract: It is the patient compliance and stability in
combination with controlled drug delivery and biocompatibility that
forms the core feature in present research and development of
sustained biodegradable patch formulation intended for wound
healing. The aim was to impart sustained degradation, sterile
formulation, significant folding endurance, elasticity,
biodegradability, bio-acceptability and strength. The optimized
formulation comprised of polymers including Hydroxypropyl methyl
cellulose, Ethylcellulose, and Gelatin, and Citric Acid PEG Citric
acid (CPEGC) triblock dendrimers and active Curcumin. Polymeric
mixture dissolved in geometric order in suitable medium through
continuous stirring under ambient conditions. With continued stirring
Curcumin was added with aid of DCM and Methanol in optimized
ratio to get homogenous dispersion. The dispersion was sonicated
with optimum frequency and for given time and later casted to form a
patch form. All steps were carried out under strict aseptic conditions.
The formulations obtained in the acceptable working range were
decided based on thickness, uniformity of drug content, smooth
texture and flexibility and brittleness. The patch kept on stability
using butter paper in sterile pack displayed folding endurance in
range of 20 to 23 times without any evidence of crack in an
optimized formulation at room temperature (RT) (24 ± 2°C). The
patch displayed acceptable parameters after stability study conducted
in refrigerated conditions (8±0.2°C) and at RT (24 ± 2°C) up to 90
days. Further, no significant changes were observed in critical
parameters such as elasticity, biodegradability, drug release and drug
content during stability study conducted at RT 24±2°C for 45 and 90
days. The drug content was in range 95 to 102%, moisture content
didn’t exceeded 19.2% and patch passed the content uniformity test.
Percentage cumulative drug release was found to be 80% in 12h and
matched the biodegradation rate as drug release with correlation
factor R2>0.9. The biodegradable patch based formulation developed
shows promising results in terms of stability and release profiles.
Abstract: An approach was evaluated for the retrieval of soil
moisture of bare soil surface using bistatic scatterometer data in the
angular range of 200 to 700 at VV- and HH- polarization. The
microwave data was acquired by specially designed X-band (10
GHz) bistatic scatterometer. The linear regression analysis was done
between scattering coefficients and soil moisture content to select the
suitable incidence angle for retrieval of soil moisture content. The 250
incidence angle was found more suitable. The support vector
regression analysis was used to approximate the function described
by the input output relationship between the scattering coefficient and
corresponding measured values of the soil moisture content. The
performance of support vector regression algorithm was evaluated by
comparing the observed and the estimated soil moisture content by
statistical performance indices %Bias, root mean squared error
(RMSE) and Nash-Sutcliffe Efficiency (NSE). The values of %Bias,
root mean squared error (RMSE) and Nash-Sutcliffe Efficiency
(NSE) were found 2.9451, 1.0986 and 0.9214 respectively at HHpolarization.
At VV- polarization, the values of %Bias, root mean
squared error (RMSE) and Nash-Sutcliffe Efficiency (NSE) were
found 3.6186, 0.9373 and 0.9428 respectively.