Abstract: In this article was evaluated the protective effect of
the alternative concrete obtained from the binary mixture of fly ash,
and iron and steel slag. After mixing the cement with aggregates,
structural steel was inserted in the matrix cementitious. The study
was conducted comparatively with specimens exposed to natural
conditions free of chloride ion. The chloride ion effect on the
specimens accelerated under controlled conditions (3.5% NaCl and
25°C temperature). The impedance data were acquired in a range of 1
mHz to 100 kHz.
Abstract: In this study, nuclear magnetic resonance
spectroscopy and nuclear quadrupole resonance spectroscopy
parameters of 14N (Nitrogen in imidazole ring) in N–H…O hydrogen
bonding for Histidine hydrochloride monohydrate were calculated via
density functional theory. We considered a five-molecule model
system of Histidine hydrochloride monohydrate. Also we examined
the trends of environmental effect on hydrogen bonds as well as
cooperativity. The functional used in this research is M06-2X which
is a good functional and the obtained results has shown good
agreement with experimental data. This functional was applied to
calculate the NMR and NQR parameters. Some correlations among
NBO parameters, NMR and NQR parameters have been studied
which have shown the existence of strong correlations among them.
Furthermore, the geometry optimization has been performed using
M062X/6-31++G(d,p) method. In addition, in order to study
cooperativity and changes in structural parameters, along with
increase in cluster size, natural bond orbitals have been employed.
Abstract: Hybrid bioreactor having both suspended-growth and
attached-growth bacteria is found a novel and excellent bioreactor
system for treating the municipal wastewater containing inhibitory
substrates too. In this reactor a fraction of substrate is used by
suspended biomass and the remaining by attached biomass resulting
in the competition between the two growths for the substrate. The
combination of suspended and attached growth provides the system
with enhanced biomass concentration and sludge age more than those
in ASP. Similar to attached growth system, the hybrid bioreactor
ensures considerable efficiency for treating toxic and refractory
substances in wastewater. For the process design of hybrid bioreactor
a suitable mathematical model is required. Although various
mathematical models were developed on hybrid bioreactor in due
course of time in earlier research works, none of them was found
having a specific simplified solution of the corresponding models and
without having any drawback. To overcome this drawback authors
already developed a simplified mathematical model for process
design of a hybrid bioreactor. The present paper briefly highlights on
the various aspects of process design of an aerobic hybrid bioreactor
for the treatment of municipal wastewater.
Abstract: Semiconductor crystals smaller than about 10 nm,
known as quantum dots, have properties that differ from large
samples, including a band gap that becomes larger for smaller
particles. These properties create several applications for quantum
dots. In this paper new shapes of quantum dot arrays are used to
enhance the photo physical properties of gold nano-particles. This
paper presents a study of the effect of nano-particles shape, array, and
size on their absorption characteristics.
Abstract: The mixed micellization of adiphenine hydrochloride (ADP) with 1-decyl-3-methylimidazolium chloride (C10mim.Cl), was investigated at different mole fractions and temperatures by surface tension measurements. The synergistic behavior (i.e., non-ideal behavior) for binary mixtures was explained by the deviation of critical micelle concentration (cmc) from ideal critical micelle concentration (cmc*), micellar mole fraction (Xim) from ideal micellar mole fraction (Xiideal), the values of interaction parameter (β) and activity coefficients (fi) (for both mixed micelles and mixed monolayer). The excess free energy (ΔGex) for the ADP- C10mim.Cl binary mixtures explain the stability of mixed micelles in comparison to micelles of pure ADP and C10mim.Cl. Interfacial parameters, i.e., Gibbs surface excess (Гmax), minimum head group area at air/ water
interface (Amin), and free energy of micellization (ΔG0m) were also evaluated for the systems.
Abstract: Co metal supported on SiO2 and Al2O3 catalysts with
a metal loading varied from 30 of 70 wt.% were evaluated for
decomposition of methane to COx free hydrogen and carbon
nanomaterials. The catalytic runs were carried out from 550-800oC
under atmospheric pressure using fixed bed vertical flow reactor. The
fresh and spent catalysts were characterized by BET surface area
analyzer, XRD, SEM, TEM and TG analysis. The data showed that
50% Co/Al2O3 catalyst exhibited remarkable higher activity at 800oC
with respect to H2 production compared to rest of the catalysts.
However, the catalytic activity and durability was greatly declined at
higher temperature. The main reason for the catalytic inhibition of Co
containing SiO2 catalysts is the higher reduction temperature of
Co2SiO4. TEM images illustrate that the carbon materials with
various morphologies, carbon nanofibers (CNFs), helical-shaped
CNFs and branched CNFs depending on the catalyst composition and
reaction temperature were obtained.
Abstract: Surface modification and functionalization has been
an important tool for scientists in order to open new frontiers in
nanoscience and nanotechnology. Desired surface characteristics for
the intended applications can be achieved with surface
functionalization.
In this work, the effect of water soluble ligands on the adsorption
capabilities of silver nanoparticles onto AC which was synthesized
from German beech wood was investigated. Sodium borohydride
(NaBH4) and polyvinyl alcohol (PVA) were used as the ligands.
Silver nanoparticles with different surface coatings have average
sizes range from 10 to 13 nm. They were synthesized in aqueous
media by reducing Ag (I) ion in the presence of ligands. These
particles displayed adsorption tendencies towards AC when they
were mixed together and shaken in distilled water.
Silver nanoparticles (NaBH4-AgNPs) reduced and stabilized by
NaBH4 adsorbed onto AC with a homogenous dispersion of
aggregates with sizes in the range of 100-400 nm. Beside, silver
nanoparticles, which were prepared in the presence of both NaBH4
and PVA (NaBH4/PVA-Ag NPs), demonstrated that NaBH4/PVA-Ag
NPs adsorbed and dispersed homogenously but, they aggregated with
larger sizes on the AC surface (range from 300 to 600 nm). In
addition, desorption resistance of Ag nanoparticles were investigated
in distilled water. According to the results AgNPs were not desorbed
on the AC surface in distilled water.
Abstract: Evaluated nuclear decay data for the 217Po nuclide is
presented in the present work. These data include recommended
values for the half-life T1/2, α-, β-- and γ-ray emission energies and
probabilities. Decay data from 221Rn α and 217Bi β—decays are
presented. Q(α) has been updated based on the recent published work
of the Atomic Mass Evaluation AME2012. In addition, the logft
values were calculated using the Logft program from the ENSDF
evaluation package. Moreover, the total internal conversion electrons
and the K-shell to L-shell and L-shell to M-shell and to N-shell
conversion electrons ratios K/L, L/M and L/N have been calculated
using Bricc program. Meanwhile, recommendation values or the
multi-polarities have been assigned based on recently measurement
yield a better intensity balance at the 254 keV and 264 keV gamma
transitions.
Abstract: Zinc oxide (ZnO) is one of the light emitting materials in ultraviolet (UV) region. In addition, ZnO nanostructures are also attracting increasing research interest as buildingblocks for UV optoelectronic applications. We have succeeded in synthesizing vertically-aligned ZnO nanostructures by laser interference patterning, which is catalyst-free and non-contact technique. In this study, vertically-aligned ZnO nanowall arrays were synthesized using two-beam interference. The maximum height and average thickness of the ZnO nanowalls were about 4.5µm and 200 nm, respectively.UV lasing from a piece of the ZnO nanowall was obtained under the third harmonic of a Q-switched Nd:YAG laser excitation, and the estimated threshold power density for lasing was about 150 kW/cm2. Furthermore, UV lasing from the vertically-aligned ZnO nanowall was also achieved. The results indicate that ZnO nanowalls can be applied to random laser.
Abstract: A nanocrystalline thin film of ZnSe was successfully
electrodeposited on copper substrate using a non-aqueous solution
and subsequently annealed in air at 400°C. XRD analysis indicates
the polycrystalline deposit of (111) plane in both the cases. The
sharpness of the peak increases due to annealing of the film and
average grain size increases to 20 nm to 27nm. SEM photograph
indicate that grains are uniform and densely distributed over the
surface. Annealing increases the average grain size by 20%. The EDS
spectroscopy shows the ratio of Zn & Se is 1.1 in case of annealed
film. AFM analysis indicates the average roughness of the film
reduces from 181nm to 165nm due to annealing of the film. The
bandgap also decreases from 2.71eV to 2.62eV.
Abstract: Mechanical stress has a strong effect on the magnitude
of the Barkhausen-noise in structural steels. Because the
measurements are performed at the surface of the material, for a
sample sheet, the full effect can be described by a biaxial stress field.
The measured Barkhausen-noise is dependent on the orientation of
the exciting magnetic field relative to the axis of the stress tensor.
The sample inhomogenities including the residual stress also
modifies the angular dependence of the measured Barkhausen-noise.
We have developed a laboratory device with a cross like specimen
for bi-axial bending. The measuring head allowed performing
excitations in two orthogonal directions. We could excite the two
directions independently or simultaneously with different amplitudes.
The simultaneous excitation of the two coils could be performed in
phase or with a 90 degree phase shift. In principle this allows to
measure the Barkhausen-noise at an arbitrary direction without
moving the head, or to measure the Barkhausen-noise induced by a
rotating magnetic field if a linear superposition of the two fields can
be assumed.
Abstract: The detection of the polymer melt state during
manufacture process is regarded as an efficient way to control the
molded part quality in advance. Online monitoring rheological
property of polymer melt during processing procedure provides an
approach to understand the melt state immediately. Rheological
property reflects the polymer melt state at different processing
parameters and is very important in injection molding process
especially. An approach that demonstrates how to calculate
rheological property of polymer melt through in-process
measurement, using injection molding as an example, is proposed in
this study. The system consists of two sensors and a data acquisition
module can process the measured data, which are used for the
calculation of rheological properties of polymer melt. The rheological
properties of polymer melt discussed in this study include shear rate
and viscosity which are investigated with respect to injection speed
and melt temperature. The results show that the effect of injection
speed on the rheological properties is apparent, especially for high
melt temperature and should be considered for precision molding
process.
Abstract: Micro-alloyed steel components are used in
automotive industry for the necessity to make the manufacturing
process cycles shorter when compared to conventional steel by
eliminating heat treatment cycles, so an important saving of costs and
energy can be reached by reducing the number of operations. Microalloying
elements like vanadium, niobium or titanium have been
added to medium carbon steels to achieve grain refinement with or
without precipitation strengthening along with uniform
microstructure throughout the matrix. Present study reports the
applicability of medium carbon vanadium micro-alloyed steel in hot
forging. Forgeability has been determined with respect to different
cooling rates, after forging in a hydraulic press at 50% diameter
reduction in temperature range of 900-11000C. Final microstructures,
hardness, tensile strength, and impact strength have been evaluated.
The friction coefficients of different lubricating conditions, viz.,
graphite in hydraulic oil, graphite in furnace oil, DF 150 (Graphite,
Water-Based) die lubricant and dry or without any lubrication were
obtained from the ring compression test for the above micro-alloyed
steel. Results of ring compression tests indicate that graphite in
hydraulic oil lubricant is preferred for free forging and dry lubricant
is preferred for die forging operation. Exceptionally good forgeability
and high resistance to fracture, especially for faster cooling rate has
been observed for fine equiaxed ferrite-pearlite grains, some amount
of bainite and fine precipitates of vanadium carbides and
carbonitrides. The results indicated that the cooling rate has a
remarkable effect on the microstructure and mechanical properties at
room temperature.
Abstract: In this research (using induction furnace process)
nodular iron with three different percentages of copper (residual,
0.5% and 1,2%) was obtained. Chemical analysis was performed by
mass spectrometry and microstructures were characterized by Optical
Microscopy (ASTM E3) and Scanning Electron Microscopy (SEM).
The study of mechanical behavior was carried out in a mechanical
test machine (ASTM E8) and a Pin on disk tribometer (ASTM G99)
was used to assess wear resistance. It is observed that the dissolution
of copper in crystal lattice increases the pearlite structure improving
the wear and hardness behavior, but producing a contrary effect on
the energy absorption.
Abstract: Doxorubicin, also known as Adriamycin, is an
anthracycline class of drug used in cancer chemotherapy. It is used in
the treatment of non-Hodgkin’s lymphoma, multiple myeloma, acute
leukemia, breast cancer, lung cancer, endometrium cancer and ovary
cancers. It functions via intercalating DNA and ultimately killing
cancer cells. The major side effects of doxorubicin are hair loss,
myelosuppression, nausea & vomiting, oesophagitis, diarrhea, heart
damage and liver dysfunction. The minor modifications in the
structure of compound exhibit large variation in the biological
activity, has prompted us to carry out the synthesis of sulfonamide
derivatives. Sulfonamide is an important feature with broad spectrum
of biological activity such as antiviral, antifungal, diuretics, antiinflammatory,
antibacterial and anticancer activities. Structure of the
synthesized compound N-(1-methyl-2-oxo-2-N-methyl anilinoethyl)
benzene sulfonamide confirmed by proton nuclear magnetic
resonance (1H NMR),13C NMR, Mass and FTIR spectroscopic tools
to assure the position of all protons and hence stereochemistry of the
molecule. Further we have reported the binding potential of
synthesized sulfonamide analogues in comparison to doxorubicin
drug using Auto Dock 4.2 software. Computational binding energy
(B.E.) and inhibitory constant (Ki) has been evaluated for the
synthesized compound in comparison of doxorubicin against Poly
(dA-dT).Poly (dA-dT) and Poly (dG-dC).Poly (dG-dC) sequences.
The in vitro cytotoxic study against human breast cancer cell lines
confirms the better anticancer activity of the synthesized compound
over currently in use anticancer drug doxorubicin. The IC50 value of
the synthesized compound is 7.12 μM whereas for doxorubicin is 7.2
μM.
Abstract: A quartz crystal microbalance (QCM) nanosensor was developed to detect lysozyme enzyme by functionalizing its gold surface with the attachment of poly(methacroyl-L-phenylalanine) (PMAPA) nanoparticles. PMAPA was chosen as a hydrophobic matrix. The hydrophobic nanoparticles were synthesized by micro-emulsion polymerization method. Hydrophobic QCM nanosensor was tested for real time detection of lysozyme enzyme from aqueous solution. The kinetic and affinity studies were determined by using lysozyme solutions with different concentrations. The responses related with mass (Δm) and frequency (Δf) shifts were used to evaluate adsorption properties.
Abstract: In order to detect and quantify the phenolic contents
of a wastewater with biosensors, two working electrodes based on
modified Poly(Pyrrole) films were fabricated. Enzyme horseradish
peroxidase was used as biomolecule of the prepared electrodes.
Various phenolics were tested at the biosensor. Phenol detection was
realized by electrochemical reduction of quinones produced by
enzymatic activity. Analytical parameters were calculated and the
results were compared with each other.
Abstract: In this article a comparison was made between Cu and
TiO2 supported catalysts on activated carbon for ozone
decomposition reaction. The activated carbon support in the case of
TiO2/AC sample was prepared by physicochemical pyrolysis and for
Cu/AC samples the supports are chemically modified carbons. The
prepared catalysts were synthesized by impregnation method. The
samples were annealed in two different regimes- in air and under
vacuum. To examine adsorption efficiency of the samples BET
method was used. All investigated catalysts supported on chemically
modified carbons have higher specific surface area compared to the
specific surface area of TiO2 supported catalysts, varying in the range
590÷620 m2/g. The method of synthesis of the precursors had
influenced catalytic activity.
Abstract: Many aluminum motorcycle parts produced by a high
pressure die casting. Some parts such as fuel caps were a thin and
complex shape. This part risked for porosities and blisters on surface
if it only depended on an experience of mold makers for mold design.
This research attempted to use CAST-DESIGNER software
simulated the high pressure die casting process with the same process
parameters of a motorcycle fuel cap production. The simulated results
were compared with fuel cap products and expressed the same
porosity and blister locations on cap surface. An average of absolute
difference of simulated results was obtained 0.094 mm when
compared the simulated porosity and blister defect sizes on the fuel
cap surfaces with the experimental micro photography. This
comparison confirmed an accuracy of software and will use the
setting parameters to improve fuel cap molds in the further work.
Abstract: The borate glasses are known by their structural
characterized by existence of unit’s structural composed by triangles
and tetrahedrons boron in different configurations depending on the
percentage of B2O3 in the glass chemical composition. In this paper,
effect of lithium oxide addition on the thermal and physical
properties of an alumina borate glass, was investigated. It was found
that the boron abnormality has a significant effect in the change of
glass properties according to the addition rate of lithium oxide.