Abstract: Construction cost in India is increasing at around 50
per cent over the average inflation levels. It have registered increase
of up to 15 per cent every year, primarily due to cost of basic
building materials such as steel, cement, bricks, timber and other
inputs as well as cost of labour. As a result, the cost of construction
using conventional building materials and construction is becoming
beyond the affordable limits particularly for low-income groups of
population as well as a large cross section of the middle - income
groups. Therefore, there is a need to adopt cost-effective construction
methods either by up-gradation of traditional technologies using local
resources or applying modern construction materials and techniques
with efficient inputs leading to economic solutions. This has become
the most relevant aspect in the context of the large volume of housing
to be constructed in both rural and urban areas and the consideration
of limitations in the availability of resources such as building
materials and finance. This paper makes an overview of the housing
status in India and adoption of appropriate and cost effective
technologies in the country.
Abstract: The field of biomedical materials plays an imperative
requisite and a critical role in manufacturing a variety of biological
artificial replacements in a modern world. Recently, titanium (Ti)
materials are being used as biomaterials because of their superior
corrosion resistance and tremendous specific strength, free- allergic
problems and the greatest biocompatibility compared to other
competing biomaterials such as stainless steel, Co-Cr alloys,
ceramics, polymers, and composite materials. However, regardless of
these excellent performance properties, Implantable Ti materials have
poor shear strength and wear resistance which limited their
applications as biomaterials. Even though the wear properties of Ti
alloys has revealed some improvements, the crucial effectiveness of
biomedical Ti alloys as wear components requires a comprehensive
deep understanding of the wear reasons, mechanisms, and techniques
that can be used to improve wear behavior. This review examines
current information on the effect of thermal and thermomechanical
processing of implantable Ti materials on the long-term prosthetic
requirement which related with wear behavior. This paper focuses
mainly on the evolution, evaluation and development of effective
microstructural features that can improve wear properties of bio
grade Ti materials using thermal and thermomechanical treatments.
Abstract: Recently, nanomaterials are developed in the form of nano-films, nano-crystals and nano-pores. Lanthanide phosphates as a material find extensive application as laser, ceramic, sensor, phosphor, and also in optoelectronics, medical and biological labels, solar cells and light sources. Among the different kinds of rare-earth orthophosphates, yttrium orthophosphate has been shown to be an efficient host lattice for rare earth activator ions, which have become a research focus because of their important role in the field of light display systems, lasers, and optoelectronic devices. It is in this context that the 4fn- « 4fn-1 5d transitions of rare earth in insulating materials, lying in the UV and VUV, are the aim of large number of studies .Though there has been a few reports on Eu3+, Nd3+, Pr3+,Er3+, Ce3+, Tm3+ doped YPO4. The 4fn- « 4fn-1 5d transitions of the rare earth dependent to the host-matrix, several matrices ions were used to study these transitions, in this work we are suggesting to study on a very specific class of inorganic material that are orthophosphate doped with rare earth ions. This study focused on the effect of Ce3+ concentration on the structural and optical properties of Ce3+ doped YPO4 yttrium orthophosphate with powder form prepared by the Sol Gel method.
Abstract: Steel corrosion in concrete is considered as a main
engineering problems for many countries and lots of expenses has been paid for their repair and maintenance annually. This problem
may occur in all engineering structures whether in coastal and offshore or other areas. Hence, concrete structures should be able to
withstand corrosion factors existing in water or soil. Reinforcing
steel corrosion enhancement can be measured by use of concrete
electrical resistance; and maintaining high electric resistivity in concrete is necessary for steel corrosion prevention. Lots of studies
devoted to different aspects of the subjects worldwide. In this paper, an evaluation of the effects of W/C ratio, cementitious materials, and
percent increase in silica fume were investigated on electric resistivity of high strength concrete. To do that, sixteen mix design
with one aggregate grading was planned. Five of them had varying amount of W/C ratio and other eleven mixes was prepared with
constant W/C ratio but different amount of cementitious materials.
Silica fume and super plasticizer were used with different proportions
in all specimens. Specimens were tested after moist curing for 28 days. A total of 80 cube specimens (50 mm) were tested for concrete
electrical resistance. Results show that concrete electric resistivity can be increased with increasing amount of cementitious materials
and silica fume.
Abstract: A specially designed flat plate was mounted vertically
over the axial line in the wind tunnel of the Aerospace Department of
the Pusan National University. The plate is 2 m long, 0.8 m high and 8
cm thick. The measurements were performed in velocity range from
15 to 60 m/s. A sand paper turbulizer was placed close to the plate nose
to provide fully developed turbulent boundary layer over the most part
of the plate. Strain balances were mounted in the trailing part of the
plate to measure the skin friction drag over removable insertions of
0.55×0.25m2 size. A set of the insertions was designed and
manufactured: 3mm thick polished metal surface and three compliant
surfaces. The compliant surfaces were manufactured of a silicone
rubber Silastic® S2 (Dow Corning company). To modify the
viscoelastic properties of the rubber, its composition was varied: 90%
of the rubber + 10% catalyst (standard), 92.5% + 7.5% (weak), 85% +
15% (strong). Modulus of elasticity and the loss tangent were
measured accurately for these materials in the frequency range from
40 Hz to 3 KHz using the unique proposed technique.
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: An attempt has been made to determine the strength
and impact properties of Cr-Mo steel weld and base materials by
varying the current during manual metal arc welding. Toughness over
a temperature range from -32 to 100°C of base, heat affected zone
(HAZ) and weld zones at three current settings are made. It is
observed that the deterioration in notch toughness at any zone with
the temperature decreases. The values of notch toughness for all
zones at -32°C are almost same for any current settings. The values
of notch toughness at HAZ area are higher than that of weld area due
to the coarsening of ferrite grain of HAZ occurs with higher heat
input. From microhardness and microstructure result, it can be
concluded that large inclusion content in weld deposit is the cause of
lower notch toughness value.
Abstract: Semiconductor materials with coatings have a wide range of applications in MEMS and NEMS. This work uses transfermatrix method for calculating the radiative properties. Dopped silicon is used and the coherent formulation is applied. The Drude model for the optical constants of doped silicon is employed. Results showed that for the visible wavelengths, more emittance occurs in greater concentrations and the reflectance decreases as the concentration increases. In these wavelengths, transmittance is negligible. Donars and acceptors act similar in visible wavelengths. The effect of wave interference can be understood by plotting the spectral properties such as reflectance or transmittance of a thin dielectric film versus the film thickness and analyzing the oscillations of properties due to constructive and destructive interferences. But this effect has not been shown at visible wavelengths. At room temperature, the scattering process is dominated by lattice scattering for lightly doped silicon, and the impurity scattering becomes important for heavily doped silicon when the dopant concentration exceeds1018cm-3 .
Abstract: This paper reviews designs of the built environment
from a sustainability perspective, emphasizing their importance in
achieving ecological and sustainable economic objectives. The built
environment has traditionally resulted in loss of biodiversity,
extinction of some species, climate change, excessive water use, land
degradation, space depletion, waste accumulation, energy
consumption and environmental pollution. Materials used like
plastics, metals, bricks, concrete, cement, natural aggregates, glass
and plaster have wreaked havoc on the earth´s resources, since they
have high levels of embodied energy hence not sustainable.
Additional resources are consumed during use and disposal phases.
Proposed designs for sustainability solutions include: ecological
sanitation and eco-efficiency systems that ensure social, economic,
environmental and technical sustainability. Renewable materials and
energy systems, passive cooling and heating systems and material
and energy reduction, reuse and recycling can improve the sector.
These ideas are intended to inform the field of ecological design of
the built environment.
Abstract: The pavement constructions on soft and expansive soils are not durable and unable to sustain heavy traffic loading. As a result, pavement failures and settlement problems will occur very often even under light traffic loading due to cyclic and rolling effects. Geotechnical engineers have dwelled deeply into this matter, and adopt various methods to improve the engineering characteristics of soft fine-grained soils and expansive soils. The problematic soils are either replaced by good and better quality material or treated by using chemical stabilization with various binding materials. Increased the strength and durability are also the part of the sustainability drive to reduce the environment footprint of the built environment by the efficient use of resources and waste recycle materials. This paper presents a series of laboratory tests and evaluates the effect of cement and fly ash on the strength and drainage characteristics of soil in Miri. The tests were performed at different percentages of cement and fly ash by dry weight of soil. Additional tests were also performed on soils treated with the combinations of fly ash with cement and lime. The results of this study indicate an increase in unconfined compression strength and a decrease in hydraulic conductivity of the treated soil.
Abstract: A piston cylinder based high pressure differential
thermal analyzer system is developed to investigate phase
transformations, melting, glass transitions, crystallization behavior of
inorganic materials, glassy systems etc., at ambient to 4 GPa and at
room temperature to 1073 K. The pressure is calibrated by the phase
transition of bismuth and ytterbium and temperature is calibrated
by using thermocouple data chart. The system developed is
calibrated using benzoic acid, ammonium nitrate and it has a
pressure and temperature control of ± 8.9 x 10 -4 GPa , ± 2 K
respectively. The phase transition of Asx Te100-x chalcogenides,
ferrous oxide and strontium boride are studied using the
indigenously developed system.
Abstract: Cerium-doped lanthanum bromide LaBr3:Ce(5%)
crystals are considered to be one of the most advanced scintillator
materials used in PET scanning, combining a high light yield, fast
decay time and excellent energy resolution. Apart from the correct
choice of scintillator, it is also important to optimise the detector
geometry, not least in terms of source-to-detector distance in order to
obtain reliable measurements and efficiency. In this study a
commercially available 25 mm x 25 mm BrilLanCeTM 380 LaBr3: Ce
(5%) detector was characterised in terms of its efficiency at varying
source-to-detector distances. Gamma-ray spectra of 22Na, 60Co, and
137Cs were separately acquired at distances of 5, 10, 15, and 20cm. As
a result of the change in solid angle subtended by the detector, the
geometric efficiency reduced in efficiency with increasing distance.
High efficiencies at low distances can cause pulse pile-up when
subsequent photons are detected before previously detected events
have decayed. To reduce this systematic error the source-to-detector
distance should be balanced between efficiency and pulse pile-up
suppression as otherwise pile-up corrections would need to be
necessary at short distances. In addition to the experimental
measurements Monte Carlo simulations have been carried out for the
same setup, allowing a comparison of results. The advantages and
disadvantages of each approach have been highlighted.
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: This paper deals with a new way for designing
external fixators applied in traumatology and orthopaedics. These
fixators can be applied in the treatment of open and unstable
fractures or for lengthening human or animal bones etc. The new
design is based on the development of Ilizarov and other techniques
(i.e. shape and weight optimalization based on composite materials,
application of smart materials, nanotechnology, low x-ray absorption,
antibacterial protection, patient's comfort, reduction in the duration
of the surgical treatment, and cost).
Abstract: This article presents the simulation, parameterization and optimization of an electromagnet with the C–shaped configuration, intended for the study of magnetic properties of materials. The electromagnet studied consists of a C-shaped yoke, which provides self–shielding for minimizing losses of magnetic flux density, two poles of high magnetic permeability and power coils wound on the poles. The main physical variable studied was the static magnetic flux density in a column within the gap between the poles, with 4cm2 of square cross section and a length of 5cm, seeking a suitable set of parameters that allow us to achieve a uniform magnetic flux density of 1x104 Gaussor values above this in the column, when the system operates at room temperature and with a current consumption not exceeding 5A. By means of a magnetostatic analysis by the finite element method, the magnetic flux density and the distribution of the magnetic field lines were visualized and quantified. From the results obtained by simulating an initial configuration of electromagnet, a structural optimization of the geometry of the adjustable caps for the ends of the poles was performed. The magnetic permeability effect of the soft magnetic materials used in the poles system, such as low– carbon steel (0.08% C), Permalloy (45% Ni, 54.7% Fe) and Mumetal (21.2% Fe, 78.5% Ni), was also evaluated. The intensity and uniformity of the magnetic field in the gap showed a high dependence with the factors described above. The magnetic field achieved in the column was uniform and its magnitude ranged between 1.5x104 Gauss and 1.9x104 Gauss according to the material of the pole used, with the possibility of increasing the magnetic field by choosing a suitable geometry of the cap, introducing a cooling system for the coils and adjusting the spacing between the poles. This makes the device a versatile and scalable tool to generate the magnetic field necessary to perform magnetic characterization of materials by techniques such as vibrating sample magnetometry (VSM), Hall-effect, Kerr-effect magnetometry, among others. Additionally, a CAD design of the modules of the electromagnet is presented in order to facilitate the construction and scaling of the physical device.
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: Novel acrylated epoxidized hemp oil (AEHO) based
bioresins were successfully synthesised, characterized and applied to
biocomposites reinforced with woven jute fibre. Characterisation of
the synthesised AEHO consisted of acid number titrations and FTIR
spectroscopy to assess the success of the acrylation reaction. Three
different matrices were produced (vinylester (VE), 50/50 blend of
AEHO/VE and 100% AEHO) and reinforced with jute fibre to form
three different types of biocomposite samples. Mechanical properties
in the form of flexural and interlaminar shear strength (ILSS) were
investigated and compared for the different samples. Results from the
mechanical tests showed that AEHO and 50/50 based neat bioresins
displayed lower flexural properties compared with the VE samples.
However when applied to biocomposites and compared with VE
based samples, AEHO biocomposites demonstrated comparable
flexural performance and improved ILSS. These results are attributed
to improved fibre-matrix interfacial adhesion due to surface-chemical
compatibility between the natural fibres and bioresin.
Abstract: In many buildings we rely on large footings to offer
structural stability. Designers often compensate for the lack of
knowledge available with regard to foundation-soil interaction by
furnishing structures with overly large footings. This may lead to a
significant increase in building expenditures if many large
foundations are present. This paper describes the interface material
law that governs the behavior along the contact surface of adjacent
materials, and the behavior of a large foundation under ultimate limit
loading. A case study is chosen that represents a common
foundation-soil system frequently used in general practice and
therefore relevant to other structures. Investigations include
compressing versus uplifting wind forces, alterations to the
foundation size and subgrade compositions, the role of the slab
stiffness and presence and the effect of commonly used structural
joints and connections. These investigations aim to provide the
reader with an objective design approach, efficiently preventing
structural instability.
Abstract: At the present, auto part industries have become higher challenge in strategy market. As this consequence, manufacturers need to have better response to customers in terms of quality, cost, and delivery time. Moreover, they need to have a good management in factory to comply with international standard maximum capacity and lower cost. This would lead companies to have to order standard part from aboard and become the major cost of inventory. The development of auto part research by recycling materials experiment is to compare the auto parts from recycle materials to international auto parts (CKD). Factors studied in this research were the recycle material ratios of PU-foam, felt, and fabric. Results of recycling materials were considered in terms of qualities and properties on the parameters such as weight, sound absorption, water absorption, tensile strength, elongation, and heat resistance with the CKD. The results were showed that recycling materials would be used to replace for the CKD.
Abstract: The aim of our work is to study phase composition,
particle size and magnetic response of Fe2O3/TiO2 nanocomposites
with respect to the final annealing temperature. Those nanomaterials
are considered as smart catalysts, separable from a liquid/gaseous
phase by applied magnetic field. The starting product was obtained
by an ecologically acceptable route, based on heterogeneous
precipitation of the TiO2 on modified g-Fe2O3 nanocrystals dispersed
in water. The precursor was subsequently annealed on air at
temperatures ranging from 200 oC to 900 oC. The samples were
investigated by synchrotron X-ray powder diffraction (S-PXRD),
magnetic measurements and Mössbauer spectroscopy. As evidenced
by S-PXRD and Mössbauer spectroscopy, increasing the annealing
temperature causes evolution of the phase composition from
anatase/maghemite to rutile/hematite, finally above 700 oC the
pseudobrookite (Fe2TiO5) also forms. The apparent particle size of
the various Fe2O3/TiO2 phases has been determined from the highquality
S-PXRD data by using two different approaches: the Rietveld
refinement and the Debye method. Magnetic response of the samples
is discussed in considering the phase composition and the particle
size.