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Donnan Dialysis Removal of Nitrate from Water: Effects of Process Parameters  [PDF]
Thouraya Turki, Raghda Hamdi, Mohamed Tlili, Mohamed Ben Amor
American Journal of Analytical Chemistry (AJAC) , 2015, DOI: 10.4236/ajac.2015.66055
Abstract: Excess or lack of levels of nitrate in drinking water is harmful to the human health, the concentration of NO-3 ions must be maintained at 50 mg/l. Donnan dialysis (DD) used as a driving force of the concentration gradient is an effective and simple technique for nitrate removal. In this paper, the transport of nitrate through an AMX anion-exchange membrane has been studied as a function of driving ion nature, receiver phase concentration, flow rate, temperature and agitation rate under Donnan dialysis condition. It was observed that the hydrodynamic conditions and temperature were the main variables affecting the transmembrane flow. As the driving ion, the chloride ion is more efficient than the hydrogeneocarbonate ion. The systematic study of the different parameters involved showed that the nitrate removal efficiency obtained with a feed synthetic nitrate solution (62 ppm) was off 96%. This efficiency slightly decreases for a tap water containing the same nitrate concentration; it was about 84%. This can be attributed to the complex ionic composition of the natural water.
Binding effects in multivalent Gibbs-Donnan equilibrium  [PDF]
Martin Castelnovo,Alex Evilevitch
Physics , 2005, DOI: 10.1209/epl/i2005-10425-3
Abstract: The classical Gibbs-Donnan equilibrium describes excess osmotic pressure associated with confined colloidal charges embedded in an electrolyte solution. In this work, we extend this approach to describe the influence of multivalent ion binding on the equilibrium force acting on a charged rod translocating between two compartments, thereby mimicking ionic effects on force balance during in vitro DNA ejection from bacteriophage. The subtle interplay between Gibbs-Donnan equilibrium and adsorption equilibrium leads to a non-monotonic variation of the ejection force as multivalent salt concentration is increased, in qualitative agreement with experimental observations.
Nonuniform Donnan Equilibrium within Bacteriophages Packed with Dna  [PDF]
Theo Odijk,Flodder Slok
Quantitative Biology , 2003,
Abstract: The curvature stress of DNA packed inside a phage is balanced against its electrostatic self-interaction. The DNA density is supposed nonuniform and as a result the Donnan effect is also inhomogeneous. The coarse-grained DNA density is a nonlinear function of the DNA radius of curvature at a given position inside the bacteriophage. It turns out that a region (or regions) exists totally free from DNA. The size of such holes is computed.
Donnan equilibrium and the osmotic pressure of charged colloidal lattices  [PDF]
M. N. Tamashiro,Yan Levin,Marcia C. Barbosa
Physics , 1998, DOI: 10.1007/s100510050192
Abstract: We consider a system composed of a monodisperse charge-stabilized colloidal suspension in the presence of monovalent salt, separated from the pure electrolyte by a semipermeable membrane, which allows the crossing of solvent, counterions, and salt particles, but prevents the passage of polyions. The colloidal suspension, that is in a crystalline phase, is considered using a spherical Wigner-Seitz cell. After the Donnan equilibrium is achieved, there will be a difference in pressure between the two sides of the membrane. Using the functional density theory, we obtained the expression for the osmotic pressure as a function of the concentration of added salt, the colloidal volume fraction, and the size and charge of the colloidal particles. The results are compared with the experimental measurements for ordered polystyrene lattices of two different particle sizes over a range of ionic strengths and colloidal volume fractions.
Paracrine Transformation to Autocrine Autonomy in Tumor Cell Proliferation and Spread. Is the Neoplastic Blood Supply a Functional Determinant of Clonality In Inducing Biologic Tumor Progressiveness?
Lawrence M. Agius
International Journal of Molecular Medicine and Advance Sciences , 2011,
Abstract: A theory of selectivity in terms of clonal progression of neoplasms might directly implicate a primary susceptibility of blood supply systems in transformation of paracrine responsiveness to autocrine autonomy. Subsequent neoplastic evolution might constitute forms of establishment of aberrant vascularity in inducing a clonality of tumor cell subpopulations that are integrally a single system of progression through transformation. In various ways, the active processes of tumor cell proliferation and spread through infiltration and metastases would paradoxically constitute systems of operative autonomy within a context of evolving influence. Indeed, clonality of neoplastic progression might involve a transformation that integrally evolves simply as patterns of aberrant blood supply both in initial establishment and in subsequent evolution towards higher tumor grades. In simple terms, perhaps, one might speak of different modes of evolving transformation of tumor cells as clonally derived cells centered on aberrant blood supply that is inherently a point of reference in terms even of basic malignant transformation as a carcinogenic event. Beyond even considerations of strict initial malignant transformation, however, aberrant blood supply systems would constitute a persistent source of transformation in establishing neoplastic progression in terms largely of biologic attributes of clonality towards transformation of paracrine responsiveness to autocrine autonomy.
Optimization of Chromium (Vi) Removal by Donnan Dialysis  [PDF]
I. Marzouk, L. Dammak, L. Chaabane, B. Hamrouni
American Journal of Analytical Chemistry (AJAC) , 2013, DOI: 10.4236/ajac.2013.46039

The removal of chromium (VI) from aqueous solutions by Donnan dialysis has been investigated in this paper. In this process, two anion-exchange membranes (AEMs) were used: Selemion? AMV and Neosepta? AFN. The amount of chromium (VI) removed was determined in terms of the following parameters: initial concentration of chromium (VI), type of anion-exchange membrane, concentration of counter-ion and magnetic stirring rate. A 24 full factorial design analysis was performed to screen the parameters affecting the Cr (VI) removal efficiency. Using the experimental results, a linear mathematical model representing the influence of the different parameters as well as their interactions was obtained. Analysis of the variance (ANOVA), the F-test and the student’s test shows that the type of anion-exchange membrane is the most significant parameter affecting the chromium (VI) removal. The statistical analysis of the experimental data assumes it to be a normal distribution.

An experiment on multibubble sonoluminescence spectra in sodium chloride solution
Zhan Chen,JunFeng Xu,Wei Huang,WeiZhong Chen,GuoQing Miao
Chinese Science Bulletin , 2008, DOI: 10.1007/s11434-008-0216-6
Abstract: We investigated experimentally the spectra of MBSL in sodium chloride water solution with krypton as dissolved gas. We observed and compared the spectra of hydroxyl ion at 310 nm and that of sodium atom at 589 nm. It has been found that under the same experimental condition, the intensity of sodium atom spectra is obviously higher than that of the hydroxyl ion spectra, and is more sensitive to the experimental condition. The krypton content, the concentration of sodium chloride solution, and the driving sound pressure obviously affect the spectra intensity in certain range.
Gibbs-Donnan Potential as a Tool for Membrane Vesicles Polarization  [PDF]
Mazur Iuliia, Kosterin Sergiy, Veklich Tetyana, Shkrabak Oleksandr
Journal of Biophysical Chemistry (JBPC) , 2014, DOI: 10.4236/jbpc.2014.52009
It has been theoretically predicted that under conditions leading to Gibbs-Donnan equilibrium in case when size of one compartment is very different from another (as in system “membrane vesicle/liposomes—incubation medium”) stable transmembrane potential can be formed, which value is sufficient to fit requirement of real transmembrane potential. Four partial cases were considered with different location and charge of impermeable ion and it was concluded that locations of impermeable ions in medium provide stable transmembrane potential with sufficient value of 60 - 70 mV. Potential-sensitive probe, such as DiOC6(3) and oxonol VI, were used to confirm the calculated potential. According to the change in fluorescence level and emission/excitation shift, a stable and relatively high transmembrane potential can be formed if salt of impermeable ion is located in incubation medium. Impermeable cations and anions may be used to create positive and negative transmembrane potential respectively.
The Residue Determinant  [PDF]
Simon Scott
Mathematics , 2004,
Abstract: The purpose of this paper is to present the construction of a canonical determinant functional on elliptic pseudodifferential operators associated to the Guillemin-Wodzicki residue trace. The resulting functional is multiplicative, a local invariant, and not defined by a regularization procedure. The residue determinant is consequently a quite different object to the zeta function (quasi-) determinant, which is non-local and non-multiplicative.
On the Quillen determinant  [PDF]
Kenro Furutani
Mathematics , 2003, DOI: 10.1016/j.geomphys.2003.07.001
Abstract: We explain the bundle structures of the {\it Determinant line bundle} and the {\it Quillen determinant line bundle} considered on the connected component of the space of Fredholm operators including the identity operator in an intrinsic way. Then we show that these two are isomorphic and that they are non-trivial line bundles and trivial on some subspaces. Also we remark a relation of the {\it Quillen determinant line bundle} and the {\it Maslov line bundle}.
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