1,691 research outputs found
Foundation Problems in a Developing City
Foundation problems are normally associated with type of sub strata, soil, rock or any other foreign material\u27 met with, and/or if choice of foundation is not compatible with them. In developing cities, the development stress is on highly developed congested areas, limiting the sub soil investigation, and plans to have high rise buildings, requiring deep foundations and sometimes execution of these posing site problems. The collapse of a multi-storeyed structure caused, according to geotechnical engineers due to overlooking the existence of a drain and a few cases of composite foundations are described
Transformations of q-boson and q-fermion algebras
We investigate the algebras satisfied by q-deformed boson and fermion
oscillators, in particular the transformations of the algebra from one form to
another. Based on a specific algebra proposed in recent literature, we show
that the algebra of deformed fermions can be transformed to that of undeformed
standard fermions. Furthermore we also show that the algebra of q-deformed
fermions can be transformed to that of undeformed standard bosons.Comment: 7 pages, RevTe
Generalized symmetric nonextensive thermostatistics and q-modified structures
We formulate a convenient generalization of the q-expectation value, based on
the analogy of the symmetric quantum groups and q-calculus, and show that the
q->q^{-1} symmetric nonextensive entropy preserves all of the mathematical
structure of thermodynamics just as in the case of non-symmetric Tsallis
statistics. Basic properties and analogies with quantum groups are discussed.Comment: 9 pages, 1 figure. To appear in Mod. Phys. Lett.
CFRP strengthened continuous concrete beams.
yesThis paper reports the testing of five reinforced concrete continuous beams strengthened in flexure with externally bonded carbon-fibre-reinforced polymer (CFRP) laminates. All beams had the same geometrical dimensions and internal steel reinforcement. The main parameters studied were the position and form of the CFRP laminates. Three of the beams were strengthened using different arrangements of CFRP plate reinforcement, and one was strengthened using CFRP sheets. The performance of the CFRP-strengthened beams was compared with that of an unstrengthened control beam. Peeling failure was the dominant mode of failure for all the strengthened beams tested. The beam strengthened with both top and bottom CFRP plates produced the highest load capacity. It was found that the longitudinal elastic shear stresses at the adhesive/concrete interface calculated at beam failure were close to the limiting value recommended in Concrete Society Technical Report 55
Elementary Quantum Mechanics in a Space-time Lattice
Studies of quantum fields and gravity suggest the existence of a minimal
length, such as Planck length \cite{Floratos,Kempf}. It is natural to ask how
the existence of a minimal length may modify the results in elementary quantum
mechanics (QM) problems familiar to us \cite{Gasiorowicz}. In this paper we
address a simple problem from elementary non-relativistic quantum mechanics,
called "particle in a box", where the usual continuum (1+1)-space-time is
supplanted by a space-time lattice. Our lattice consists of a grid of
rectangles, where , the lattice
parameter, is a fundamental length (say Planck length) and, we take to
be equal to . The corresponding Schrodinger equation becomes a
difference equation, the solution of which yields the -eigenfunctions and
-eigenvalues of the energy operator as a function of . The
-eigenfunctions form an orthonormal set and both -eigenfunctions and
-eigenvalues reduce to continuum solutions as
The corrections to eigenvalues because of the assumed lattice is shown to be
We then compute the uncertainties in position and momentum,
for the box problem and study the consequent modification
of Heisenberg uncertainty relation due to the assumption of space-time lattice,
in contrast to modifications suggested by other investigations such as
\cite{Floratos}
Preparation, Characterization and In Vitro Drug Release Studies of 6-mercaptopurine Thin Film
Oral thin films of 6-mercaptopurine were fabricated from mucoadhesive polymer, chitosan and polyvinylpyrrolidone for the purpose of prolonging drug release and improving its bioavailability. All fabricated film formulations prepared were smooth and translucent, with good flexibility. The weight and thickness of all the formulations were found to be uniform. These films were also evaluated for surface pH, folding endurance, swelling percentage (% S) and in vitro disintegration time. Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FTIR) were used to evaluate the physico-chemical nature of the films. In-vitro drug release have shown enhanced release profiles for thin films compared to pure drug and the release patterns have been found to be pH dependant. The results of the study reveals that fabrication of 6-MP oral thin film by using solvent cast technology is a simple and an efficient method for drug delivery to achieve desired therapeutic compliance.Keywords: 6-mercaptopurine; In Vitro Drug Release; SEM; FTI
Generalized thermodynamics of q-deformed bosons and fermions
We study the thermostatistics of q-deformed bosons and fermions obeying the
symmetric algebra and show that it can be built on the formalism of q-calculus.
The entire structure of thermodynamics is preserved if ordinary derivatives are
replaced by an appropriate Jackson derivative. In this framework, we derive the
most important thermodynamic functions describing the q-boson and q-fermion
ideal gases in the thermodynamic limit. We also investigate the semi-classical
limit and the low temperature regime and demonstrate that the nature of the
q-deformation gives rise to pure quantum statistical effects stronger than
undeformed boson and fermion particles.Comment: 8 pages, Physical Review E in pres
Pressure-induced amorphization and polyamorphism in one-dimensional single crystal TiO2 nanomaterials
The structural phase transitions of single crystal TiO2-B nanoribbons were
investigated in-situ at high-pressure using the synchrotron X-ray diffraction
and the Raman scattering. Our results have shown a pressure-induced
amorphization (PIA) occurred in TiO2-B nanoribbons upon compression, resulting
in a high density amorphous (HDA) form related to the baddeleyite structure.
Upon decompression, the HDA form transforms to a low density amorphous (LDA)
form while the samples still maintain their pristine nanoribbon shape. HRTEM
imaging reveals that the LDA phase has an {\alpha}-PbO2 structure with short
range order. We propose a homogeneous nucleation mechanism to explain the
pressure-induced amorphous phase transitions in the TiO2-B nanoribbons. Our
study demonstrates for the first time that PIA and polyamorphism occurred in
the one-dimensional (1D) TiO2 nanomaterials and provides a new method for
preparing 1D amorphous nanomaterials from crystalline nanomaterials.Comment: 4 figure
Detailed Balance and Intermediate Statistics
We present a theory of particles, obeying intermediate statistics ("anyons"),
interpolating between Bosons and Fermions, based on the principle of Detailed
Balance. It is demonstrated that the scattering probabilities of identical
particles can be expressed in terms of the basic numbers, which arise naturally
and logically in this theory. A transcendental equation determining the
distribution function of anyons is obtained in terms of the statistics
parameter, whose limiting values 0 and 1 correspond to Bosons and Fermions
respectively. The distribution function is determined as a power series
involving the Boltzmann factor and the statistics parameter and we also express
the distribution function as an infinite continued fraction. The last form
enables one to develop approximate forms for the distribution function, with
the first approximant agreeing with our earlier investigation.Comment: 13 pages, RevTex, submitted for publication; added references; added
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STABILITY INDICATING HPLC METHOD FOR DETERMINATION OF VILAZODONE HYDROCHLORIDE
Objective: The aim and objective of this study was to develop and validate Stability Indicating HPLC method for determination of Vilazodone Hydrochloride.Methods: The method was carried out on a Phenomenex, C18 (250x4.6 mm, 5 µm) Column using a mixture of Acetonitrile: Water (50:50v/v), pH adjusted to 3.3 with Glacial Acetic Acid for separation. The flow rate was adjusted at 1 ml/min and Detection was carried out at 240 nm.Results: The retention time of vilazodone hydrochloride was found to be 2.3 min. The calibration curve was found to be linear in the range 25-75µg/ml with a correlation coefficient (R2=0.996). The limit of detection and limit of quantitation were found to be 4.78µg/ml and 14.48µg/ml respectively. The % recovery of vilazodone hydrochloride was found to be in the range of 98.21±0.08 % to 99.07±0.64%. The proposed method was successfully applied for the estimation of vilazodone hydrochloride in marketed tablet formulation.Vilazodone Hydrochloride was subjected to forced degradation under Acidic, Alkaline, Oxidation, Dry Heat and Photolytic degradation conditions. Vilazodone hydrochloride showed 3.12% degradation under acidic condition, 4.78% under alkaline condition, 7.8% under oxidation condition, 3.53% under dry heat condition and 4.9% under photolytic condition.Acid degradation impurity was identified and characterised by LC-MS/MS was found to be 1-(4-Penten-1-yl) piperazine having molecular weight 154.253 (m/z 155.08) and Molecular Formula C9H18N2.Conclusion: A simple, precise, rapid and accurate Stability Indicating HPLC method has been developed and validated for the determination of Vilazodone Hydrochloride in presence of its degradation products as per the ICH Guidelines.Â
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