Abstract: The present work was conducted for Arsenic (III)
removal, which one of the most poisonous groundwater pollutants, by
synthetic nano size zerovalent iron (nZVI). Batch experiments were
performed to investigate the influence of As (III), nZVI
concentration, pH of solution and contact time on the efficiency of As
(III) removal. nZVI was synthesized by reduction of ferric chloride
by sodium borohydrid. SEM and XRD were used to determine
particle size and characterization of produced nanoparticles. Up to
99.9% removal efficiency for arsenic (III) was obtained by nZVI
dosage of 1 g/L at time equal to 10 min. and pH=7. It could be
concluded that the removal efficiency were enhanced with increasing
of ZVI dosage and reaction time, but decreased with increasing of
arsenic concentration and pH for nano sized ZVI. nZVI presented an
outstanding ability to remove As (III) due to not only a high surface
area and low particle size but also to high inherent activity.
Abstract: Particle detection in very noisy and low contrast images
is an active field of research in image processing. In this article, a
method is proposed for the efficient detection and sizing of subsurface
spherical particles, which is used for the processing of softly fused
Au nanoparticles. Transmission Electron Microscopy is used for
imaging the nanoparticles, and the proposed algorithm has been
tested with the two-dimensional projected TEM images obtained.
Results are compared with the data obtained by transmission optical
spectroscopy, as well as with conventional circular object detection
algorithms.
Abstract: Determination of nano particle size is substantial since
the nano particle size exerts a significant effect on various properties
of nano materials. Accordingly, proposing non-destructive, accurate
and rapid techniques for this aim is of high interest. There are some
conventional techniques to investigate the morphology and grain size
of nano particles such as scanning electron microscopy (SEM),
atomic force microscopy (AFM) and X-ray diffractometry (XRD).
Vibrational spectroscopy is utilized to characterize different
compounds and applied for evaluation of the average particle size
based on relationship between particle size and near infrared spectra
[1,4] , but it has never been applied in quantitative morphological
analysis of nano materials. So far, the potential application of nearinfrared
(NIR) spectroscopy with its ability in rapid analysis of
powdered materials with minimal sample preparation, has been
suggested for particle size determination of powdered
pharmaceuticals. The relationship between particle size and diffuse
reflectance (DR) spectra in near infrared region has been applied to
introduce a method for estimation of particle size. Back propagation
artificial neural network (BP-ANN) as a nonlinear model was applied
to estimate average particle size based on near infrared diffuse
reflectance spectra. Thirty five different nano TiO2 samples with
different particle size were analyzed by DR-FTNIR spectrometry and
the obtained data were processed by BP- ANN.
Abstract: Coarse and fine particulate matter were collected at a
residential area at Vashi, Navi Mumbai and the filter samples were
analysed for trace elements using PIXE technique. The trend of
particulate matter showed higher concentrations during winter than
the summer and monsoon concentration levels. High concentrations
of elements related to soil and sea salt were found in PM10 and
PM2.5. Also high levels of zinc and sulphur found in the particulates
of both the size fractions. EF analysis showed enrichment of Cu, Cr
and Mn only in the fine fraction suggesting their origin from
anthropogenic sources. The EF value was observed to be maximum
for As, Pb and Zn in the fine particulates. However, crustal derived
elements showed very low EF values indicating their origin from
soil. The PCA based multivariate studies identified soil, sea salt,
combustion and Se sources as common sources for coarse and
additionally an industrial source has also been identified for fine
particles.
Abstract: Cancer becomes one of the leading cause of death in
many countries over the world. Fourier-transform infrared (FTIR)
spectra of human lung cancer cells (A549) treated with PMF (natural
product extracted from PM 701) for different time intervals were
examined. Second derivative and difference method were taken in
comparison studies. Cesium (Cs) and Rubidium (Rb) nanoparticles in
PMF were detected by Energy Dispersive X-ray attached to Scanning
Electron Microscope SEM-EDX. Characteristic changes in protein
secondary structure, lipid profile and changes in the intensities of
DNA bands were identified in treated A549 cells spectra. A
characteristic internucleosomal ladder of DNA fragmentation was
also observed after 30 min of treatment. Moreover, the pH values
were significantly increases upon treatment due to the presence of Cs
and Rb nanoparticles in the PMF fraction. These results support the
previous findings that PMF is selective anticancer agent and can
produce apoptosis to A549 cells.
Abstract: Concrete performance is strongly affected by the
particle packing degree since it determines the distribution of the
cementitious component and the interaction of mineral particles. By
using packing theory designers will be able to select optimal
aggregate materials for preparing concrete with low cement content,
which is beneficial from the point of cost. Optimum particle packing
implies minimizing porosity and thereby reducing the amount of
cement paste needed to fill the voids between the aggregate particles,
taking also the rheology of the concrete into consideration. For
reaching good fluidity superplasticizers are required. The results from
pilot tests at Luleå University of Technology (LTU) show various
forms of the proposed theoretical models, and the empirical approach
taken in the study seems to provide a safer basis for developing new,
improved packing models.
Abstract: The possibility of using cassava residue containing
49.66% starch, 21.47% cellulose, 12.97% hemicellulose, and 21.86%
lignin as a raw material to produce glucose using enzymatic
hydrolysis was investigated. In the experiment, each reactor
contained the cassava residue, bacteria cells, and production medium.
The effects of particles size (40 mesh and 60 mesh) and strains of
bacteria (A002 and M015) isolated from Thai higher termites,
Microcerotermes sp., on the glucose concentration at 37°C were
focused. High performance liquid chromatography (HPLC) with a
refractive index detector was used to determine the quantity of
glucose. The maximum glucose concentration obtained at 37°C using
strain A002 and 60 mesh of the cassava residue was 1.51 g/L at 10 h.
Abstract: Smart Dust particles, are small smart materials used for generating weather maps. We investigate question of the optimal number of Smart Dust particles necessary for generating precise, computationally feasible and cost effective 3–D weather maps. We also give an optimal matching algorithm for the generalized scenario, when there are N Smart Dust particles and M ground receivers.
Abstract: Since injection engines have a considerable portion, in
consumption of energy and environmental pollution, using an
alternative source of energy with lower pollutant effects in this
regard is necessary.
Biodiesel fuel is a suitable alternative for gasoline in diesel
engines.
In this research the property of biodiesel, the function and the
pollution effects of diesel engine, when using 100% biodiesel, using
100% gasoline and mixing ratio of both fuels for comparing them,
have been investigated.
The researches have shown, using biodiesel fuel in prevalent
diesel engine, will reduce the pollutants such as Co, half burned
carbohydrate and suspended particles and a little increase in
oxidation will achieve while power consumption, particularly fuel
and thermal efficiency of diesel fuel has the same.
Abstract: This study determines the effect of naked and heparinbased
super-paramagnetic iron oxide nanoparticles on the human
cancer cell lines of A2780. Doxorubicin was used as the anticancer
drug, entrapped in the SPIO-NPs. This study aimed to decorate
nanoparticles with heparin, a molecular ligand for 'active' targeting
of cancerous cells and the application of modified-nanoparticles in
cancer treatment. The nanoparticles containing the anticancer drug
DOX were prepared by a solvent evaporation and emulsification
cross-linking method. The physicochemical properties of the
nanoparticles were characterized by various techniques, and uniform
nanoparticles with an average particle size of 110±15 nm with high
encapsulation efficiencies (EE) were obtained. Additionally, a
sustained release of DOX from the SPIO-NPs was successful.
Cytotoxicity tests showed that the SPIO-DOX-HP had higher cell
toxicity than the individual HP and confocal microscopy analysis
confirmed excellent cellular uptake efficiency. These results indicate
that HP based SPIO-NPs have potential uses as anticancer drug
carriers and also have an enhanced anticancer effect.
Abstract: The effects of down slope steepness on soil splash distribution under a water drop impact have been investigated in this study. The equipment used are the burette to simulate a water drop, a splash cup filled with sandy soil which forms the source area and a splash board to collect the ejected particles. The results found in this study have shown that the apparent mass increased with increasing downslope angle following a linear regression equation with high coefficient of determination. In the same way, the radial soil splash distribution over the distance has been analyzed statistically, and an exponential function was the best fit of the relationship for the different slope angles. The curves and the regressions equations validate the well known FSDF and extend the theory of Van Dijk.
Abstract: Nanostructured Iron Oxide with different
morphologies of rod-like and granular have been suc-cessfully
prepared via a solid-state reaction in the presence of NaCl, NaBr, NaI
and NaN3, respectively. The added salts not only prevent a drastic
increase in the size of the products but also provide suitable
conditions for the oriented growth of primary nanoparticles. The
formation mechanisms of these materials by solid-state reaction at
ambient temperature are proposed. The photocatalytic experiments
for congo red (CR) have demonstrated that the mixture of α-Fe2O3
and Fe3O4 nanostructures were more efficient than α-Fe2O3
nanostructures.
Abstract: The coalescer process is one of the methods for oily water treatment by increasing the oil droplet size in order to enhance the separating velocity and thus effective separation. However, the presence of surfactants in an oily emulsion can limit the obtained mechanisms due to the small oil size related with stabilized emulsion. In this regard, the purpose of this research is to improve the efficiency of the coalescer process for treating the stabilized emulsion. The effects of bed types, bed height, liquid flow rate and stage coalescer (step-bed) on the treatment efficiencies in term of COD values were studied. Note that the treatment efficiency obtained experimentally was estimated by using the COD values and oil droplet size distribution. The study has shown that the plastic media has more effective to attach with oil particles than the stainless one due to their hydrophobic properties. Furthermore, the suitable bed height (3.5 cm) and step bed (3.5 cm with 2 steps) were necessary in order to well obtain the coalescer performance. The application of step bed coalescer process in reactor has provided the higher treatment efficiencies in term of COD removal than those obtained with classical process. The proposed model for predicting the area under curve and thus treatment efficiency, based on the single collector efficiency (ηT) and the attachment efficiency (α), provides relatively a good coincidence between the experimental and predicted values of treatment efficiencies in this study.
Abstract: Application of nanoparticles as additives in membrane
synthesis for improving the resistance of membranes against fouling
has triggered recent interest in new membrane types. However, most
nanoparticle-enhanced membranes suffer from the tradeoff between
permeability and selectivity. In this study, nano-WS2 was explored as
the additive in membrane synthesis by non-solvent induced phase
separation. Blended PES-WS2 flat-sheet membranes with the
incorporation of ultra-low concentrations of nanoparticles (from 0.025
to 0.25%, WS2/PES ratio) were manufactured and investigated in
terms of permeability, fouling resistance and solute rejection.
Remarkably, a significant enhancement in the permeability was
observed as a result of the incorporation of ultra-low fractions of
nano-WS2 to the membrane structure. Optimal permeability values
were obtained for modified membranes with 0.10%
nanoparticle/polymer concentration ratios. Furthermore, fouling
resistance and solute rejection were significantly improved by the
incorporation of nanoparticles into the membrane matrix. Specifically,
fouling resistance of modified membrane can increase by around 50%.
Abstract: The peculiarities of the nanoscale structure-phase
states formed after electroexplosive carburizing and subsequent
electron-beam treatment of technically pure titanium surface in different regimes are established by methods of transmission electron
diffraction microscopy and physical mechanisms are discussed. Electroexplosive carburizing leads to surface layer formation
(40 m thickness) with increased (in 3.5 times) microhardness. It consists of β-titanium, graphite (monocrystals 100-150 nm,
polycrystals 5-10 nm, amorphous particles 3-5nm), TiC (5-10 nm), β-Ti02 (2-20nm). After electron-beam treatment additionally increasing the microhardness the surface layer consists of TiC.
Abstract: Today, cancer remains one of the major diseases that
lead to death. The main obstacle in chemotherapy as a main cancer
treatment is the toxicity to normal cells due to Multidrug Resistance
(MDR) after the use of anticancer drugs. Proposed solution to
overcome this problem is the use of MDR efflux inhibitor of cinchona
alkaloids which is delivered together with anticancer drugs
encapsulated in the form of polymeric nanoparticles. The particles
were prepared by the hydration method. The characterization of
nanoparticles was particle size, zeta potential, entrapment efficiency
and in vitro drug release. Combination nanoparticle size ranged 29-45
nm with a neutral surface charge. Entrapment efficiency was above
87% for the use quinine, quinidine or cinchonidine in combination
with etoposide. The release test results exhibited that the cinchona
alkaloids release released faster than that of etoposide. Collectively,
cinchona alkaloids can be packaged along with etoposide in
nanomicelles for better cancer therapy.
Abstract: The morphological parameter of a thin film surface
can be characterized by power spectral density (PSD) functions
which provides a better description to the topography than the RMS
roughness and imparts several useful information of the surface
including fractal and superstructure contributions. Through the
present study Nanoparticle copper/carbon composite films were
prepared by co-deposition of RF-Sputtering and RF-PECVD method
from acetylene gas and copper target. Surface morphology of thin
films is characterized by using atomic force microscopy (AFM). The
Carbon content of our films was obtained by Rutherford Back
Scattering (RBS) and it varied from .4% to 78%. The power values of
power spectral density (PSD) for the AFM data were determined by
the fast Fourier transform (FFT) algorithms. We investigate the effect
of carbon on the roughness of thin films surface. Using such
information, roughness contributions of the surface have been
successfully extracted.