Abstract: The effect of the inclusion of thyme and rosemary
essential oils into chitosan films, as well as the microbiological and
physical properties when storing chitosan film with and without the
mentioned inclusion was studied. The film forming solution was
prepared by dissolving chitosan (2%, w/v), polysorbate 80 (4% w/w
CH) and glycerol (16% w/w CH) in aqueous lactic acid solutions
(control). The thyme (TEO) and rosemary (REO) essential oils (EOs)
were included 1:1 w/w (EOs:CH) on their combination 50/50
(TEO:REO). The films were stored at temperatures of 5, 20, 33°C
and a relative humidity of 75% during four weeks. The films with
essential oil inclusion did not show an antimicrobial activity against
strains. This behavior could be explained because the chitosan only
inhibits the growth of microorganisms in direct contact with the
active sites. However, the inhibition capacity of TEO was higher than
the REO and a synergic effect between TEO:REO was found for S.
enteritidis strains in the chitosan solution.
Some physical properties were modified by the inclusion of
essential oils. The addition of essential oils does not affect the
mechanical properties (tensile strength, elongation at break, puncture
deformation), the water solubility, the swelling index nor the DSC
behavior. However, the essential oil inclusion can significantly
decrease the thickness, the moisture content, and the L* value of
films whereas the b* value increased due to molecular interactions
between the polymeric matrix, the loosing of the structure, and the
chemical modifications. On the other hand, the temperature and time
of storage changed some physical properties on the chitosan films.
This could have occurred because of chemical changes, such as
swelling in the presence of high humidity air and the reacetylation of
amino groups. In the majority of cases, properties such as moisture
content, tensile strength, elongation at break, puncture deformation,
a*, b*, chrome, 7E increased whereas water resistance, swelling
index, L*, and hue angle decreased.
Abstract: Chemical Reaction Optimization (CRO) is an
optimization metaheuristic inspired by the nature of chemical
reactions as a natural process of transforming the substances from
unstable to stable states. Starting with some unstable molecules with
excessive energy, a sequence of interactions takes the set to a state of
minimum energy. Researchers reported successful application of the
algorithm in solving some engineering problems, like the quadratic
assignment problem, with superior performance when compared with
other optimization algorithms. We adapted this optimization
algorithm to the Printed Circuit Board Drilling Problem (PCBDP)
towards reducing the drilling time and hence improving the PCB
manufacturing throughput. Although the PCBDP can be viewed as
instance of the popular Traveling Salesman Problem (TSP), it has
some characteristics that would require special attention to the
transactions that explore the solution landscape. Experimental test
results using the standard CROToolBox are not promising for
practically sized problems, while it could find optimal solutions for
artificial problems and small benchmarks as a proof of concept.
Abstract: Welfare may be considered to be a subjective
experience; it has a biological function that is related to the fitness
and survival of the animal accordingly, researches have suggested
that welfare is compromised when the animal's evolutionary fitness is
reduced. This study was carried out to explain the effect of some
managerial stressors as handling and restraint on behavioral patterns
and biochemical parameters of rats. A total of 24 (12 males & 12
females) Sprague-Dawley rats (12 months & 150-180g) were allotted
into 3 groups, handled group (4 male & 4 female), restrained group (4
male & 4 female) and control group (4 males & 4 females).
The obtained results revealed that time spent feeding, drinking,
movement and cage exploration frequencies increased significantly in
handled rats than other groups, while lying time and licking increased
significantly in restrained rats than handled and controls. Moreover,
social behavior decreased in both stressed groups than control.
Triglycerides were significantly increased in handled rats than
other groups, while total lipid, total protein and globulin significantly
increased in both treated groups than control. Corticosterone
increased in restrained and handled rats than control ones. Moreover,
there was an increment in packed cell volume significantly in
restrained rats than others. These deducted that if we want to study
the effect of stress on animal welfare it is necessary to study the
effect of such stressors on animal’s behavior and physiological
responses.
Abstract: Food as perishable goods represents a specific and
sensitive part in the supply chain theory, since changing physical or
chemical characteristics considerably influence the approach to stock
management. The most delicate phase of this process is
transportation, where it becomes difficult to ensure the stable
conditions which limit deterioration, since the value of the
deterioration rate could be easily influenced by the mode of
transportation. The fuzzy definition of variables allows one to take
these variations into account. Furthermore, an appropriate choice of
the defuzzification method permits one to adapt results to real
conditions as far as possible. In this article those methods which take
into account the relationship between the deterioration rate of
perishable goods and transportation by ship will be applied with the
aim of (a) minimizing the total cost function, defined as the sum of
the ordering cost, holding cost, disposing cost and transportation
costs, and (b) improving the supply chain sustainability by reducing
environmental impact and waste disposal costs.
Abstract: Alkylated silicon nanocrystals (C11-SiNCs) were
prepared successfully by galvanostatic etching of p-Si(100) wafers
followed by a thermal hydrosilation reaction of 1-undecene in
refluxing toluene in order to extract C11-SiNCs from porous silicon.
Erbium trichloride was added to alkylated SiNCs using a simple
mixing chemical route. To the best of our knowledge, this is the first
investigation on mixing SiNCs with erbium ions (III) by this
chemical method. The chemical characterization of C11-SiNCs and
their mixtures with Er3+(Er/C11-SiNCs) were carried out using X-ray
photoemission spectroscopy (XPS). The optical properties of C11-
SiNCs and their mixtures with Er3+ were investigated using Raman
spectroscopy and photoluminescence (PL). The erbium mixed
alkylated SiNCs shows an orange PL emission peak at around 595
nm that originates from radiative recombination of Si. Er/C11-SiNCs
mixture also exhibits a weak PL emission peak at 1536 nm that
originates from the intra-4f transition in erbium ions (Er3+). The PL
peak of Si in Er/C11-SiNCs mixture is increased in the intensity up to
three times as compared to pure C11-SiNCs. The collected data
suggest that this chemical mixing route leads instead to a transfer of
energy from erbium ions to alkylated SiNCs.
Abstract: Strong anion exchange resins with QN+OH-, have the
potential to be developed and employed as heterogeneous catalyst for
transesterification, as they are chemically stable to leaching of the
functional group. Nine different SIERs (SIER1-9) with QN+OH-were
prepared by suspension polymerization of vinylbenzyl chloridedivinylbenzene
(VBC-DVB) copolymers in the presence of n-heptane
(pore-forming agent). The amine group was successfully grafted into
the polymeric resin beads through functionalization with
trimethylamine. These SIERs are then used as a catalyst for the
transesterification of triacetin with methanol. A set of differential
equations that represents the Langmuir-Hinshelwood-Hougen-
Watson (LHHW) and Eley-Rideal (ER) models for the
transesterification reaction were developed. These kinetic models of
LHHW and ER were fitted to the experimental data. Overall, the
synthesized ion exchange resin-catalyzed reaction were welldescribed
by the Eley-Rideal model compared to LHHW models,
with sum of square error (SSE) of 0.742 and 0.996, respectively.
Abstract: Developing young people’s employability is a key
policy issue for ensuring their successful transition to the labour
market and their access to career oriented employment. The youths of
today irrespective of their gender need to acquire the knowledge,
skills and attitudes that will enable them to create or find jobs as well
as cope with unpredictable labour market changes throughout their
working lives. In a study carried out to determine the influence of
gender on job-competencies requirements of chemical-based
industries and undergraduate-competencies acquisition by chemists
working in the industries, all chemistry graduates working in twenty
(20) chemical-based industries that were randomly selected from six
sectors of chemical-based industries in Lagos and Ogun States of
Nigeria were administered with Job-competencies required and
undergraduate-competencies acquired assessment questionnaire. The
data were analysed using means and independent sample t-test. The
findings revealed that the population of female chemists working in
chemical-based industries is low compared with the number of male
chemists; furthermore, job-competencies requirements are found not
to be gender biased while there is no significant difference in
undergraduate-competencies acquisition of male and female
chemists. This suggests that females should be given the same
opportunity of employment in chemical-based industries as their male
counterparts. The study also revealed the level of acquisition of
undergraduate competencies as related to the needs of chemicalbased
industries.
Abstract: Liposome plays an important role in medical and
pharmaceutical science as e.g. nano scale drug carriers. Liposomes
are vesicles of varying size consisting of a spherical lipid bilayer and
an aqueous inner compartment. Magnet-driven liposome used for the
targeted delivery of drugs to organs and tissues. These liposome
preparations contain encapsulated drug components and finely
dispersed magnetic particles.
Liposomes are vesicles of varying size consisting of a spherical
lipid bilayer and an aqueous inner compartment that are generated in
vitro. These are useful in terms of biocompatibility, biodegradability,
and low toxicity, and can control biodistribution by changing the size,
lipid composition, and physical characteristics. Furthermore,
liposomes can entrap both hydrophobic and hydrophilic drugs and are
able to continuously release the entrapped substrate, thus being useful
drug carriers. Magnetic liposomes (MLs) are phospholipid vesicles
that encapsulate magneticor paramagnetic nanoparticles. They are
applied as contrast agents for magnetic resonance imaging (MRI).
The biological synthesis of nanoparticles using plant extracts plays
an important role in the field of nanotechnology. Green-synthesized
magnetite nanoparticles-protein hybrid has been produced by treating
Iron (III) / Iron (II) chloride with the leaf extract of Datura inoxia.
The phytochemicals present in the leaf extracts act as a reducing as
well stabilizing agents preventing agglomeration, which include
flavonoids, phenolic compounds, cardiac glycosides, proteins and
sugars.
The magnetite nanoparticles-protein hybrid has been trapped
inside the aqueous core of the liposome prepared by reversed phase
evaporation (REV) method using oleic and linoleic acid which has
been shown to be driven under magnetic field confirming the
formation magnetic liposome (ML). Chemical characterization of
stealth magnetic liposome has been performed by breaking the
liposome and release of magnetic nanoparticles. The presence iron
has been confirmed by colour complex formation with KSCN and
UV-Vis study using spectrophotometer Cary 60, Agilent.
This magnet driven liposome using nanoparticles-protein hybrid
can be a smart vesicles for the targeted drug delivery.
Abstract: In this research, waterglass based aerogel powder was
prepared by sol–gel process and ambient pressure drying. Inspired by
limited dust releasing, aerogel powder was introduced to the PET
electrospinning solution in an attempt to create required bulk and
surface structure for the nanofibers to improve their hydrophobic and
insulation properties. The samples evaluation was carried out by
measuring density, porosity, contact angle, heat transfer, FTIR, BET,
and SEM. According to the results, porous silica aerogel powder was
fabricated with mean pore diameter of 24 nm and contact angle of
145.9º. The results indicated the usefulness of the aerogel powder
confined into nanofibers to control surface roughness for
manipulating superhydrophobic nanowebs with water contact angle
of 147º. It can be due to a multi-scale surface roughness which was
created by nanowebs structure itself and nanofibers surface
irregularity in presence of the aerogels while a layer of fluorocarbon
created low surface energy. The wettability of a solid substrate is an
important property that is controlled by both the chemical
composition and geometry of the surface. Also, a decreasing trend in
the heat transfer was observed from 22% for the nanofibers without
any aerogel powder to 8% for the nanofibers with 4% aerogel
powder. The development of thermal insulating materials has become
increasingly more important than ever in view of the fossil energy
depletion and global warming that call for more demanding energysaving
practices.
Abstract: The tomato is a very important crop, whose
cultivation in the Mediterranean basin is severely affected by the
phytoparasitic weed Phelipanche ramosa. The semiarid regions of
the world are considered the main areas where this parasitic weed is
established causing heavy infestation as it is able to produce high
numbers of seeds (up to 500,000 per plant), which remain viable for
extended period (more than 20 years). In this paper the results
obtained from eleven treatments in order to control this parasitic
weed including chemical, agronomic, biological and biotechnological
methods compared with the untreated test under two plowing depths
(30 and 50 cm) are reported. The split-plot design with 3 replicates
was adopted. In 2014 a trial was performed in Foggia province
(southern Italy) on processing tomato (cv Docet) grown in the field
infested by Phelipanche ramosa. Tomato seedlings were transplant
on May 5, on a clay-loam soil. During the growing cycle of the
tomato crop, at 56-78 and 92 days after transplantation, the number
of parasitic shoots emerged in each plot was detected. At tomato
harvesting, on August 18, the major quantity-quality yield parameters
were determined (marketable yield, mean weight, dry matter, pH,
soluble solids and color of fruits). All data were subjected to analysis
of variance (ANOVA) and the means were compared by Tukey's test.
Each treatment studied did not provide complete control against
Phelipanche ramosa. However, among the different methods tested,
some of them which Fusarium, gliphosate, radicon biostimulant and
Red Setter tomato cv (improved genotypes obtained by Tilling
technology) under deeper plowing (50 cm depth) proved to mitigate
the virulence of the Phelipanche ramose attacks. It is assumed that
these effects can be improved combining some of these treatments
each other, especially for a gradual and continuing reduction of the
“seed bank” of the parasite in the soil.
Abstract: To develop AZ91D magnesium alloys with improved
properties, we have applied TiN and VN/TiN multilayer coatings
using DC magnetron sputter technique. Coating structure, surface
morphology, chemical bonding and corrosion resistance of coatings
were analyzed by x-ray diffraction (XRD), scanning electron
microscope (SEM), x-ray photoelectron spectroscopy (XPS), and
tafel extrapolation method, respectively. XPS analysis reveal that VN
overlayer reacts with oxygen at the VN/TiN interface and forms more
stable TiN layer. Morphological investigations and the corrosion
results show that VN/TiN multilayer thin film coatings are quite
effective to optimize the corrosion resistance of Mg alloys.
Abstract: Machining parameters are very important in
determining the surface quality of any material. In the past decade,
some new engineering materials were developed for the
manufacturing industry which created a need to conduct an
investigation on the impact of the said parameters on their surface
roughness. Polyurethane (PU) block is widely used in the automotive
industry to manufacture parts such as checking fixtures that are used
to verify the dimensional accuracy of automotive parts. In this paper,
the design of experiment (DOE) was used to investigate on the effect
of the milling parameters on the PU block. Furthermore, an analysis
of the machined surface chemical composition was done using
scanning electron microscope (SEM). It was found that the surface
roughness of the PU block is severely affected when PU undergoes a
flood machining process instead of a dry condition. In addition the
stepover and the silicon content were found to be the most significant
parameters that influence the surface quality of the PU block.
Abstract: Bamboo is extensively used in construction industry.
Low durability of bamboo due to fungus infestation and termites
attack under storage puts certain constrains for it usage as modern
structural material. Looking at many chemical formulations for
bamboo treatment leading to severe harmful environment effects,
research on eco-friendly preservatives for bamboo treatment has been
initiated world-over. In the present studies, eco-friendly preservative
for bamboo treatment has been developed. To validate its application
for structural purposes, investigation of effect of treatment on
compressive strength has been investigated. Neemoil (25%)
integrated with copper naphthenate (0.3%) on dilution with kerosene
oil impregnated into bamboo culm at 2 bar pressure, has shown
weight loss of only 3.15% in soil block analysis method. The results
from compressive strength analysis using HEICO Automatic
Compression Testing Machine reveal that preservative treatment has
not altered the structural properties of bamboo culms. Compressive
strength of control (11.72 N/mm2) and above treated samples (11.71
N/mm2) was found to be comparable.
Abstract: This study presents an attempt to evaluate the
antioxidant potential and antimicrobial activity of methanolic extract,
and essential oils prepared from the leaves of sage (Salvia officinalis
L.). The content of polyphenol in the methanolic extracts from the
leaves of Salvia officinalis was determined spectrophotometrically,
calculated as gallic acid and catechin equivalent. The essential oils
and methanol extract were also subjected to screenings for the
evaluation of their antioxidant activities using 2, 2-diphenyl-1-
picrylhydrazyl (DPPH) test. While the plant essential oils showed
only weak antioxidant activities, its methanol extract was
considerably active in DPPH (IC50 = 37.29 μg/ml) test. Appreciable
total polyphenol content (31.25 mg/g) was also detected for the plant
methanol extract as gallic acid equivalent in the Folin–Ciocalteu test.
The plant was also screened for its antimicrobial activity and good to
moderate inhibitions were recorded for its essential oils, and
methanol extracts against most of the tested microorganisms.
The present investigation revealed that this plant had rich source
of antioxidant properties. It is for this reason that sage has found
increasing application in food formulations.
Abstract: The edge waviness in hot rolled steel is a common
defect. Variables that affect such defect include raw material and
machine. These variables are necessary to consider to understand
such defect. This research studied the defect of edge waviness for SS
400 of metal sheet manufacture. Defect of metal sheets were divided
into two groups. The specimens were investigated on chemical
composition and mechanical properties to find the difference. The
results of investigation showed that the difference was not significant.
Therefore the roll mill machine should be used to adjust to support
another location on a roller to avoide edge waviness.
Abstract: Carbon nanotube is one of the most attractive materials
for the potential applications of nanotechnology due to its excellent
mechanical, thermal, electrical and optical properties. In this paper we
report a supercapacitor made of nickel foil electrodes, coated with
multiwall carbon nanotubes (MWCNTs) thin film using
electrophoretic deposition (EPD) method. Chemical vapor deposition
method was used for the growth of MWCNTs and ethanol was used as
a hydrocarbon source. High graphitic multiwall carbon nanotube was
found at 750oC analyzing by Raman spectroscopy. We observed the
electrochemical performance of supercapacitor by cyclic
voltammetry. The electrodes of supercapacitor fabricated from
MWCNTs exhibit considerably small equivalent series resistance
(ESR), and a high specific power density. Electrophoretic deposition
is an easy method in fabricating MWCNT electrodes for high
performance supercapacitor.
Abstract: In this study, microcrystalline cellulose (MCC) was
extracted from oil palm empty fruit bunch (EFB) cellulose which was
earlier isolated from oil palm EFB fibre. In order to isolate the
cellulose, the chlorination method was carried out. Then, the MCC
was prepared by simultaneous ultrasonic and alkali treatment from
the isolated α-cellulose. Based on mass balance calculation, the yields
for MCC obtained from EFB was 44%. For fiber characterization, it
is observed that the chemical composition of the hemicellulose and
lignin for all samples decreased while composition for cellulose
increased. The structural property of the MCC was studied by X-ray
diffraction (XRD) method and the result shows that the MCC
produced is a cellulose-I polymorph, with 73% crystallinity.
Abstract: Corrosion inhibitors are widely used in concrete
industry to reduce the corrosion rate of steel rebar which is present in
contact with aggressive environments. The present work aims to
using Zamzam water from well located within the Masjid al-Haram
in Mecca, Saudi Arabia 20 m (66 ft) east of the Kaaba, the holiest
place in Islam as corrosion inhibitor for steel in rain water and
simulated acid rain. The effect of Zamzam water was investigated by
electrochemical impedance spectroscopy (EIS) and Potentiodynamic
polarization techniques in Department of Civil Engineering - IUT
Saint-Nazaire, Nantes University, France. Zamzam water is
considered to be one of the most important steel corrosion inhibitor
which is frequently used in different industrial applications. Results
showed that zamzam water gave a very good inhibition for steel
corrosion in rain water and simulated acid rain.
Abstract: The present study was conducted to evaluate the
potential applicability of biological trickling filter system for the
treatment of simulated textile wastewater containing reactive azo
dyes with bacterial consortium under non-sterile conditions. The
percentage decolorization for the treatment of wastewater containing
structurally different dyes was found to be higher than 95% in all
trials. The stable bacterial count of the biofilm on stone media of the
trickling filter during the treatment confirmed the presence,
proliferation, dominance and involvement of the added microbial
consortium in the treatment of textile wastewater. Results of
physicochemical parameters revealed the reduction in chemical
oxygen demand (58.5-75.1%), sulphates (18.9-36.5%), and
phosphates (63.6-73.0%). UV-Visible and FTIR spectroscopy
confirmed decolorization of dye containing wastewater was ultimate
consequence of biodegradation. Toxicological studies revealed the
nontoxic nature of degradative metabolites.
Abstract: In this work, a polyaniline/Iron oxide (PANI/Fe2O3)
composite was chemically prepared by oxidative polymerization of
aniline in acid medium, in presence of ammonium persulphate as an
oxidant and amount of Fe2O3. The composite was characterized by a
scanning electron microscopy (SEM). The prepared composite has
been used as adsorbent to remove Tartrazine dye form aqueous
solutions.
The effects of initial dye concentration and temperature on the
adsorption capacity of PANI/Fe2O3 for Tartrazine dye have been
studied in this paper.
The Langmuir and Freundlich adsorption models have been used
for the mathematical description of adsorption equilibrium data. The
best fit is obtained using the Freundlich isotherm with an R2 value of
0.998. The change of Gibbs energy, enthalpy, and entropy of
adsorption has been also evaluated for the adsorption of Tartrazine
onto PANI/ Fe2O3. It has been proved according the results that the
adsorption process is endothermic in nature.