Abstract: The elastic properties and fracture of two-dimensional
graphene were calculated purely from the atomic bonding (stretching
and bending) based on molecular mechanics method. Considering the
representative unit cell of graphene under various loading conditions,
the deformations of carbon bonds and the variations of the interlayer
distance could be realized numerically under the geometry constraints
and minimum energy assumption. In elastic region, it was found that
graphene was in-plane isotropic. Meanwhile, the in-plane deformation
of the representative unit cell is not uniform along armchair direction
due to the discrete and non-uniform distributions of the atoms. The
fracture of graphene could be predicted using fracture criteria based on
the critical bond length, over which the bond would break. It was
noticed that the fracture behavior were directional dependent, which
was consistent with molecular dynamics simulation results.
Abstract: In this study, the feasibility of incorporating ceramic
waste from bricks (perforated brick and double hollow brick) and
extruded polystyrene (XPS) waste, is analysed.
Results show that it is possible to incorporate up to 25% of
ceramic waste and 4% of XPS waste over the weight of gypsum in a
gypsum matrix. Furthermore, with the addition of ceramic waste an
8% of surface hardness increase and a 25% of capillary water
absorption reduction can be obtained. On the other hand, with the
addition of XPS, a 26% reduction of density and a 37% improvement
of thermal conductivity can be obtained.
The obtained results are favorable to use these materials in order to
produce prefabricated gypsum and also as material for interior
cladding walls.
Abstract: Currently, continuous two-phase decanter process
used for olive oil production is the more internationally widespread.
The wastewaters generated from this industry (OMW) are a real
environmental problem because of its high organic load. Among
proposed treatments for these wastewaters, advanced oxidation
technologies (Fenton, ozone, photoFenton, etc.) are the most
favourable. The direct application of these processes is somewhat
expensive. Therefore, the application of a previous stage based on a
flocculation-sedimentation operation is of high importance. In this
research five commercial flocculants (three cationic, and two anionic)
have been used to achieve the separation of phases (liquid clarifiedsludge).
For each flocculant, different concentrations (0-1000 mg/L)
have been studied. In these experiments, sludge volume formed and
the final water quality were determined. The final removal
percentages of total phenols (11.3-25.1%), COD (5.6-20.4%), total
carbon (2.3-26.5%), total organic carbon (1.50-23.8%), total nitrogen
(1.45-24.8%), and turbidity (27.9-61.4%) were determined. The
variation on electric conductivity reduction percentage (1-8%) was
also determined. Finally, the best flocculants with highest removal
percentages have been determined (QG2001 and Flocudex CS49).
Abstract: This paper aims to study the effect of cold work
condition on the microstructure of Cu-1.5wt%Ti, and Cu-3.5wt%Ti
and hence mechanical properties. The samples under investigation
were machined, and solution heat treated. X-ray diffraction technique
is used to identify the different phases present after cold deformation
by compression and also different heat treatment and also measuring
the relative quantities of phases present. The metallographic
examination is used to study the microstructure of the samples. The
hardness measurements were used to indicate the change in
mechanical properties. The results are compared with the mechanical
properties obtained by previous workers. Experiments on cold
compression followed by aging of Cu-Ti alloys have indicated that
the most efficient hardening of the material results from continuous
precipitation of very fine particles within the matrix. These particles
were reported to be β`-type, Cu4Ti phase. The β`-β transformation
and particles coarsening within the matrix as well as long grain
boundaries were responsible for the overaging of Cu-1.5wt%Ti and
Cu-3.5wt%Ti alloys. It is well known that plate-like particles are β –
type, Cu3Ti phase. Discontinuous precipitation was found to start at
the grain boundaries and expand into grain interior. At the higher
aging temperature, a classic Widmanstätten morphology forms giving
rise to a coarse microstructure comprised of α and the equilibrium
phase β. Those results were confirmed by X-ray analysis, which
found that a few percent of Cu3Ti, β precipitates are formed during
aging at high temperature for long time for both Cu- Ti alloys (i.e.
Cu-1.5wt%Ti and Cu-3.5wt%Ti).
Abstract: Haynes 25 alloy (also known as L-605 alloy) is cobalt
based super alloy which has widely applications such as aerospace
industry, turbine and furnace parts, power generators and heat
exchangers and petroleum refining components due to its excellent
characteristics. However, the workability of this alloy is more
difficult compared to normal steels or even stainless. In present work,
an experimental investigation was performed under cryogenic
cooling to determine cutting tool wear patterns and obtain optimal
cutting parameters in turning of cobalt based superalloy Haynes 25.
In experiments, uncoated carbide tool was used and cutting speed (V)
and feed rate (f) were considered as test parameters. Tool wear
(VBmax) were measured for process performance indicators.
Analysis of variance (ANOVA) was performed to determine the
importance of machining parameters.
Abstract: In this paper, some limit properties for mixing random
variables sequences were studied and some results on weak law of
large number for mixing random variables sequences were presented.
Some complete convergence theorems were also obtained. The results
extended and improved the corresponding theorems in i.i.d random
variables sequences.
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: We used live E. coli containing synthetic genetic
oscillators to study how the degree of synchrony between the genetic
circuits of sister cells changes with temperature. We found that both
the mean and the variability of the degree of synchrony between the
fluorescence signals from sister cells are affected by temperature.
Also, while most pairs of sister cells were found to be highly
synchronous in each condition, the number of asynchronous pairs
increased with increasing temperature, which was found to be due to
disruptions in the oscillations. Finally we provide evidence that these
disruptions tend to affect multiple generations as opposed to
individual cells. These findings provide insight in how to design
more robust synthetic circuits and in how cell division can affect their
dynamics.
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: In this paper, the energy saving and human thermal
comfort in a typical office room are investigated. The impact of a
combined system of exhaust inlet air with light slots located at the
ceiling level in a room served by displacement ventilation system is
numerically modelled. Previous experimental data are used to
validate the Computational Fluid Dynamic (CFD) model. A case
study of simulated office room includes two seating occupants, two
computers, two data loggers and four lamps. The combined system is
located at the ceiling level above the heat sources. A new method of
calculation for the cooling coil load in Stratified Air Distribution
(STRAD) system is used in this study. The results show that 47.4%
energy saving of space cooling load can be achieved by combing the
exhaust inlet air with light slots at the ceiling level above the heat
sources.
Abstract: The effect of processing on plasma lipid profile and
atherogenic indices of rats fed Artocarpus heterophyllus seed diets at
different concentrations were investigated. Fifty five rats were used
for this study, they were divided into eleven groups of five rats each
(one control group and ten test groups), the test groups were fed raw,
boiled, roasted, fermented and soaked diets at 10% and 40%
concentrations. The study lasted for thirty five days. The diets led to
significant decrease (p
Abstract: Mustard leaves are rich in folates, vitamin A, K and
B-complex. Mustard greens are low in calories and fats and rich in
dietary fiber. They are rich in potassium, manganese, iron, copper,
calcium, magnesium and low in sodium. It is very rich in antioxidants
and Phytonutrients. For the optimization of process variables
(moisture content and mustard leave powder), the experiments were
conducted according to central composite Face Centered Composite
design of RSM. The mustard leaves powder was replaced with
composite flour (a combination of rice, chickpea and corn in the ratio
of 70:15:15). The extrudate was extruded in a twin screw extruder at
a barrel temperature of 120°C. The independent variables were
mustard leaves powder (2-10 %) and moisture content (12-20 %).
Responses analyzed were bulk density, water solubility index, water
absorption index, lateral expansion, antioxidant activity, total
phenolic content, and overall acceptability. The optimum conditions
obtained were 7.19 g mustard leaves powder in 100g premix having
16.8% moisture content (w.b).
Abstract: This study aims at developing a novel cold asphalt
concrete binder course mixture by using Ordinary Portland Cement
(OPC) as a replacement for conventional mineral filler (0%-100%)
with new by-product material (LJMU-A2) used as a supplementary
cementitious material. With this purpose, cold asphalt concrete binder
course mixtures with cationic emulsions were studied by means of
stiffness modulus whereas water sensitivity was assessed by
measuring the stiffness modulus ratio before and after sample
conditioning.
The results indicate that a substantial enhancement in the stiffness
modulus and a considerable improvement of water sensitivity
resistance is achieved by adding LJMU-A2 to the cold asphalt
mixtures as a supplementary cementitious material. Moreover, the
addition of LJMU-A2 to those mixtures leads to a stiffness modulus
after 2-day curing compared to that obtained with Portland cement,
which occurs after 7-day curing.
Abstract: Mitigating soil erosion, especially in Mediterranean
countries such as Greece, is essential in order to maintain
environmental and agricultural sustainability. In this paper, scientific
publications related to soil erosion studies in Greece were reviewed
and categorized. To accomplish this, the online search engine of
Scopus was used. The key words were “soil”, “erosion” and
“Greece.” An analysis of the published articles was conducted at
three levels: i) type of publication, ii) chronologic and iii) thematic. A
hundred and ten publications published in scientific journals were
reviewed. The results showed that the awareness regarding the soil
erosion in Greece has increased only in the last decades. The
publications covered a wide range of thematic categories such as the
type of studied areas, the physical phenomena that trigger and
influence the soil erosion, the negative anthropogenic impacts on
them, the assessment tools that were used in order to examine the
threat and the proper management. The analysis of these articles was
significant and necessary in order to find the scientific gaps of soil
erosion studies in Greece and help enhance the sustainability of soil
management in the future.
Abstract: Background: Delayed onset muscle soreness (DOMS)
is the most common symptom when ordinary individuals and athletes
are exposed to unaccustomed physical activity, especially eccentric
contraction which impairs athletic performance, ordinary people
work ability and physical functioning. Multitudes of methods have
been investigated to reduce DOMS. One of the valuable methods to
control DOMS is repeated bout effect (RBE) as a prophylactic
method. Purpose: To compare the repeated bout effect of
submaximal eccentric with maximal isometric contraction on induced
DOMS. Methods: Sixty normal male volunteers were assigned
randomly into three equal groups: Group A (first study group): 20
subjects received submaximal eccentric contraction on non-dominant
elbow flexors as a prophylactic exercise. Group B (second study
group): 20 subjects received maximal isometric contraction on nondominant
elbow flexors as a prophylactic exercise. Group C (control
group): 20 subjects did not receive any prophylactic exercises.
Maximal isometric peak torque of elbow flexors and patient related
elbow evaluation (PREE) scale were measured for each subject 3
times before, immediately after, and 48 hours after induction of
DOMS. Results: Post-hoc test for maximal isometric peak torque and
PREE scale immediately and 48 hours after induction of DOMS
revealed that group (A) and group (B) resulted in significant decrease
in maximal isometric strength loss and elbow pain and disability
rather than control group (C), but submaximal eccentric group (A)
was more effective than maximal isometric group (B) as it showed
more rapid recovery of functional strength and less degrees of elbow
pain and disability. Conclusion: Both submaximal eccentric
contraction and maximal isometric contraction were effective in
prevention of DOMS but submaximal eccentric contraction produced
a greater protective effect against muscle damage induced by
maximal eccentric exercise performed 2 days later.
Abstract: This paper presents Carrier Sense Multiple Access
(CSMA) communication models based on SoC design methodology.
Such a model can be used to support the modeling of the complex
wireless communication systems. Therefore, the use of such
communication model is an important technique in the construction
of high-performance communication. SystemC has been chosen
because it provides a homogeneous design flow for complex designs
(i.e. SoC and IP-based design). We use a swarm system to validate
CSMA designed model and to show how advantages of incorporating
communication early in the design process. The wireless
communication created through the modeling of CSMA protocol that
can be used to achieve communication between all the agents and to
coordinate access to the shared medium (channel).
Abstract: Interstitial free steels possess better formability and
have many applications in automotive industries. Forming limit
diagrams (FLDs) indicate the formability of materials which can be
determined by experimental and finite element (FE) simulations.
FLDs were determined experimentally by LDH test, utilizing optical
strain measurement system for measuring the strains in different
width specimens and by FE simulations in Interstitial Free (IF) and
Interstitial Free High Strength (IFHS) steels. In this study, the
experimental and FE simulated FLDs are compared and also the
stress based FLDs were investigated.
Abstract: Market is an important factor for start-ups to look into
during decision-making in product development and related areas.
Emerging country markets are more uncertain in terms of information
availability and institutional supports. The literature review of market
uncertainty reveals the need for identifying factors representing the
market uncertainty. This paper identifies factors for market
uncertainty using Exploratory Factor Analysis (EFA) and confirmed
the number of factor retention using an alternative factor retention
criterion ‘Parallel Analysis’. 500 entrepreneurs, engaged in start-ups
from all over India participated in the study. This paper concludes
with the factor structure of ‘market uncertainty’ having dimensions of
uncertainty in industry orientation, uncertainty in customer
orientation and uncertainty in marketing orientation.
Abstract: Mobil Producing Nigeria Unlimited (MPNU), a
subsidiary of ExxonMobil and the highest crude oil & condensate
producer in Nigeria has its operational base and an oil terminal, the
Qua Iboe terminal (QIT) located at Ibeno, Nigeria. Other oil
companies like Network Exploration and Production Nigeria Ltd,
Frontier Oil Ltd; Shell Petroleum Development Company Ltd; Elf
Petroleum Nigeria Ltd and Nigerian Agip Energy, a subsidiary of the
Italian ENI E&P operate onshore, on the continental shelf and in deep
offshore of the Atlantic Ocean, respectively with the coastal waters of
Ibeno, Nigeria as the nearest shoreline. This study was designed to
delineate the oil-polluted sites in Ibeno, Nigeria using
microbiological and physico-chemical characterization of soils,
sediments and ground and surface water samples from the study area.
Results obtained revealed that there have been significant recent
hydrocarbon inputs into this environment as observed from the high
counts of hydrocarbonoclastic microorganisms in excess of 1% at all
the stations sampled. Moreover, high concentrations of THC, BTEX
and heavy metals contents in all the samples analyzed corroborate the
high recent crude oil input into the study area. The results also
showed that the pollution of the different environmental media
sampled were of varying degrees, following the trend: ground water
> surface water > sediments > soils.
Abstract: Land Use Land Cover (LULC) changes due to human
activities and natural causes have become a major environmental
concern. Assessment of temporal remote sensing data provides
information about LULC impacts on environment. Land Surface
Temperature (LST) is one of the important components for modeling
environmental changes in climatological, hydrological, and
agricultural studies. In this study, LULC changes (September 7, 1984
and July 8, 2014) especially in agricultural lands together with
population changes (1985-2014) and LST status were investigated
using remotely sensed and census data in South Marmara Watershed,
Turkey. LULC changes were determined using Landsat TM and
Landsat OLI data acquired in 1984 and 2014 summers. Six-band TM
and OLI images were classified using supervised classification
method to prepare LULC map including five classes including Forest
(F), Grazing Land (G), Agricultural Land (A), Water Surface (W),
Residential Area-Bare Soil (R-B) classes. The LST image was also
derived from thermal bands of the same dates.
LULC classification results showed that forest areas, agricultural
lands, water surfaces and residential area-bare soils were increased as
65751 ha, 20163 ha, 1924 ha and 20462 ha respectively. In
comparison, a dramatic decrement occurred in grazing land (107985
ha) within three decades. The population increased 29% between
years 1984-2014 in whole study area. Along with the natural causes,
migration also caused this increase since the study area has an
important employment potential. LULC was transformed among the
classes due to the expansion in residential, commercial and industrial
areas as well as political decisions. In the study, results showed that
agricultural lands around the settlement areas transformed to
residential areas in 30 years.
The LST images showed that mean temperatures were ranged
between 26-32°C in 1984 and 27-33°C in 2014. Minimum
temperature of agricultural lands was increased 3°C and reached to
23°C. In contrast, maximum temperature of A class decreased to
41°C from 44°C. Considering temperatures of the 2014 R-B class and
1984 status of same areas, it was seen that mean, min and max
temperatures increased by 2°C.
As a result, the dynamism of population, LULC and LST resulted
in increasing mean and maximum surface temperatures, living
spaces/industrial areas and agricultural lands.