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The hepatobiliary system refers to the liver, gall bladder and bile ducts – organs that are involved with the production, Storage, transport and release of bile, a secretion that prepared fats for further digestion There are numerous conditions that can harm the hepatobiliary system, some of which are life threatening and ultimately, require surgery and/or liver transplantation. Liver damage can occur from a variety of sources: infections with viruses (hepatitis A, B, and C viruses), exposure to toxic drugs or chemicals, excessive use of alcohol, genetic disorders, diabetes, heart failure, cancer and shock In many cases, the liver is able to repair itself; in others, a variety of treatments may be effective. However, if liver damage is severe, the organ may not recover, resulting in liver failure which is life threatening. Once this happens, the patient may need a new liver.

Blend membranes made of chitosan (CS) and poly(vinyl pyrrolidone) (PVP), were synthesized and characterized for their ion exchange capacity (IEC) and Swelling Index to investigate their applicability in direct methanol fuel cells (DMFC). These membranes were assessed for their intermolecular interactions and thermal stability using FT-IR, X-ray diffraction methods, and TGA. Their methanol permeability and proton conductivity were also estimated and compared to that of Nafion 117. In addition to being effective methanol barriers, the membranes have a high ion exchange capacity (IEC) and possess adequate thermal stability. Crosslinking the polymer blend using glutaraldehyde and sulfuric acid has been particularly effective in producing a reduction of methanol permeability from 9.2 × 10 −8 cm 2 s −1 for CS/PVP blend to 7.3 × 10 −8 cm 2 s −1 for crosslinked CS/PVP blend (GS-CS/PVP) and enhancing the conductivity from 0.019 S cm −1 for CS/PVP blend to 0.024 S cm −1 for GS-CS/PVP, thereby rendering it more suitable for a DMFC. Low methanol permeability, excellent physico-mechanical properties and above all, the cost effectiveness could make their use in DMFC quite attractive.

Prevention of chemical processing disasters largely depends on assessment of thermal stability, mutual compatibility, and decomposition characteristics of materials used in the process. Such studies also facilitate a priori evaluation of vulnerability in operations and can be conveniently organized in the “process development studies” phase of the selected process. However, investigations conducted after the accidents invariably reveal that almost all the major incidents could have been avoided. This suggests an inadequate safety assessment and the vulnerability of a chosen process. Recent literature indicates that, in addition to the areas previously discussed, specific attention should be paid to the behavior of process materials under critical conditions. Quantification of a potential hazard, before an accident, often leads to modifications in design of the equipment and operating conditions, for example, to avoid serious accidents. © 2006 American Institute of Chemical Engineers Process Saf Prog, 2006

Hydropericardium syndrome has caused huge economic losses to the poultry industry in Pakistan. The disease was reported for the first time in 1987 at Angara Goth, a broiler producing area near Kara...

The viability of using polyion complex (PIC) membranes made by blending 84% deacetylated chitosan and sodium alginate biopolymers for direct methanol fuel cell (DMFC) was investigated. The membranes were characterized by FTIR to verify the polyion complex formation, XRD to observe the effects of blending on crystallinity, DSC and TGA to assess the thermal stability, and tensile testing for mechanical stability. Absorption studies were carried out to evaluate the interaction with water and methanol. The blend was found to be suitable for DMFC applications because of the low methanol permeability (4.6 × 10 −8 cm 2 /s at 50 vol.% methanol concentration), excellent physico-mechanical properties and relatively high proton conductivity (0.042 S cm −1 ). Above all, the cost effectiveness and simple fabrication technique involved in the synthesis of such PICs make their applicability in DMFC quite attractive and cost-effective.

The paper presents the application of information technology (IT) tools to a laboratory course for measurement, analysis, design, and simulation of typical electric and electronic circuits. It shows modern computer data acquisition systems used for measurement of real circuits, mathematical software IT tools used for theoretical analysis and design, and circuit simulation software IT tools used for the development of a virtual laboratory. It illustrates how spreadsheets and other IT tools are used for data recording and/or result comparisons among measurement, theoretical calculation, and simulation. The paper shows the mechanisms and approaches developed for strong correlation between theories and hands-on experimentation using modern computer tools for the purpose of quality education of the laboratory course in electric and electronic circuits.

Fuel cells represent a clean alternative to current technologies for utilizing hydrocarbon fuel resources. Polymer electrolyte membrane fuel cells (PEMFCs) have acquired due importance as they are best suited for applications where a quick start up is required such as in automobiles. The prime requirements of fuel cell membranes are high proton conductivity, low methanol/water permeability, good mechanical and thermal stability and moderate price. Membranes and the operating parameters together have a profound influence on performance of PEMFCs. Perfluorinated ionomers, hydrocarbon and aromatic polymers and acid–base complexes have been described in the review. The performance of this special class of polymers, considering their structure–property relationship and the current research involving their applicability in fuel cell systems are presented. Modifications made to Nafion ® membranes, the conceptual design of substitutes for perfluorosulfonic acid materials and modifications made to aromatic membranes to render them suitable for this application have been summarized. Promising avenues for further research in this area have been identified. © 2005 Published by Elsevier B.V.

The separation of Pb2+ from aqueous solutions was studied using a fibrous type polypyrrole thorium(IV) phosphate cation-exchanger column. This type of organic–inorganic composite material was prepared by incorporating polypyrrole into inorganic precipitate of Th(IV) phosphate, providing a new class of hybrid cation-exchangers with good ion-exchange capacity, higher stability, reproducibility and selectivity for heavy metals. The physico-chemical properties of this material were determined using some instrumental analyses. Ion-exchange capacity, pH-titrations, elution and distribution behavior etc. were also carried out to understand the ion-exchange behavior of the material. On the basis of distribution studies, the material was found to be highly selective for Pb(II) and its selectivity was examined by achieving some important binary separations like Pb(II)–Zn(II), Pb(II)–Al(III), Pb(II)–Mg(II), Zn(II)–Hg(II) etc. on its column that indicate its utility in environmental pollution control in one-way or other. For the determination of Pb(II) ions in solutions, a new heterogeneous precipitate based selective ion-sensitive membrane electrode was developed by means of this composite cation-exchanger as electroactive material. The membrane electrode is mechanically stable, with a quick response time, and can be operated over a wide pH range. The selectivity coefficients were determined by mixed solution method and revealed that the electrode is selective for Pb(II) in presence of interfering cations. The practical utility of this membrane electrode has been established by employing it as an indicator electrode in the potentiometric titration of Pb(II).

The viability of using composite membranes of heteropolyacid (HPA)/polysulfone (PSF), HPA/sulfonated polysulfone (SPSF) for use in proton exchange membrane fuel cells (PEMFC) was investigated. PSF and its sulfonated polymer, SPSF was solution-blended with phosphotungstic acid, a commercially available HPA. Fourier transform infrared (FTIR) spectroscopy of the HPA–40/SPSF composite exhibited band shifts showing a possibility of intermolecular hydrogen bonding interaction between the HPA additive and the sulfonated polymer. The composite membranes exhibited improved mechanical strength and low water uptake. The conductivity of the composite membrane, HPA–40/SPSF, consisting of 40 wt % HPA and 60 wt % SPSF [with a degree of Sulfonation (DS) of 40%] exhibited a conductivity 0.089 S/cm at room temperature that linearly increased upto 0.14 S/cm at 120 °C, whereas the widely used commercial membrane Nafion 117, exhibited a room temperature conductivity of 0.1 S/cm that increased to only 0.12 S/cm at 120 °C. In contrast, the composite of HPA–40/PSF exhibited a proton conductivity of 0.02 S/cm at room temperature that increased only to 0.07 S/cm at a temperature of 100 °C. The incorporation of HPA into SPSF not only rendered the membranes suitable for elevated temperature operation of PEMFC but also provides an inexpensive alternative compared to Nafion. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1538–1547, 2005

Membranes made of poly(vinyl alcohol) (PVA) and its ionic blends with sodium alginate (SA) and chitosan were synthesized and characterized for their ion-exchange capacity (IEC) and swelling index values to investigate their applicability in direct methanol fuel cells (DMFCs). These membranes were assessed for their intermolecular interactions, thermal stabilities, and mechanical strengths with Fourier transform infrared spectroscopy, X-ray diffraction methods, differential scanning calorimetry, thermogravimetric analysis, and tensile testing, respectively. Methanol permeability and proton conductivity were also estimated and compared to that of Nafion 117. In addition to being effective methanol barriers, the membranes had a considerably high IEC and thermal and mechanical stabilities. The addition of small amounts of anionic polymer was particularly instrumental in the significant reduction of methanol permeability from 8.1 × 10−8 cm2/s for PVA to 6.9 × 10−8 cm2/s for the PVA–SA blend, which rendered the blend more suitable for a DMFC. Low methanol permeability, excellent physicomechanical properties, and above all, cost effectiveness could make the use of these blends in DMFCs quite attractive. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 95: 1154–1163, 2005

Ionically cross-linked polyelectrolyte complex (PEC) membranes of cationic chitosan (CS) and anionic poly(acrylic acid) (PAAc) were synthesized and assessed for applicability in fuel cells. CS and PAAc were blended in different weight ratios and the resulting membranes were posttreated to enable the formation of the polyelectrolyte complex. The ionic cross-linking occurring on blending the polyelectrolytes excludes the need of using other cross-linking agents. These membranes were extensively characterized for morphology, their intermolecular interactions, thermal stability, and physicomechanical properties using SEM, FTIR, DSC, sorption studies, and tensile testing, respectively. Methanol permeability and proton conductivity were estimated and compared with respective values for Nafion 117. PEC membranes exhibited high ion exchange capacity (IEC), high proton conductivity, low methanol permeability, and adequate thermal and mechanical stability. Among the blends synthesized, the membrane blend with 50 wt...

Commercial polymers with aryl backbones such as polystyrene (PS), polycarbonate (PC), polysulfone (PSf) and poly (phenylene oxide) (PPO) were sulfonated using suitable reagents, and assessed for their potential to serve as proton exchange membranes (PEM) in fuel cells (FCs). The membranes thus synthesized were characterized by Fourier transform infra-red (FTIR) and 1 H NMR to verify sulfonation and to identify the sites available for proton conduction. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) studies were carried out to investigate the thermal stability of the sulfonated membranes. Surface morphology and tensile strength were evaluated by scanning electron microscopy (SEM) and UTM, respectively. Sorption experiments were conducted to observe the interaction of sulfonated polymers with water and methanol. The ion exchange capacity (IEC), which is a measure of proton conductivity, and the degree of substitution (DS) were evaluated and found to be comparable with the commercially available Nafion membranes. Sulfonated polycarbonate (SPC) was found to possess all the requisite properties of a PEM; namely, high IEC (0.57 meq./g), tensile strength (157 N/mm2) and thermal stability (Tg=120 °C) besides low affinity towards methanol (%sorption=2.97). The study reveals the possibility of developing inexpensive and sturdy fuel cell membranes, which could provide attractive alternatives to substitute the expensive commercially available membranes.

Hydrazine hydrate is now produced worldwide by an ecofriendly process using ammonia and hydrogen peroxide as reactants, with methylethylketone (MEK) and acetamide being other active ingredients. Ketazine is an intermediate product during the formation of which, phase separation occurs between an upper organic layer enriched in ketazine and lower aqueous phase containing substantial amounts of acetamide (30 wt.%) and methylethylketone (5%) which have to be recycled in the form of a concentrated solution after partial removal of water (60%). The membrane based pervaporation (PV) technique has been successfully applied using the chemically compatible and highly hydrophilic chitosan membrane to dehydrate the highly alkaline aqueous layer. The effect of operating parameters such as feed composition and barrier thickness on membrane performance with respect to acetamide separation and water flux has been evaluated. High degree of acetamide separation was achieved along with reasonably good water flux and MEK separation.

Reverse osmosis (RO) is a well-established process for water desalination and effluent treatment and it is anticipated that its application could be extended to complex mixtures of industrial effluents. Pilot-scale experiments using a spiral-wound thin-film composite (TFC) polyamide membrane were carried out to investigate the potential of RO for processing a composite effluent, which was a mixture of various wastewaters from bulk drug and pharmaceutical factories. Separation performance was evaluated at various feed pressures (0–70 bar) and feed concentrations (2–30 gdm−3), and was found to improve with increasing pressure. High rejection of dissolved solids (∼98%), COD, BOD and almost complete removal of color were achieved with reasonable flux rates and water recovery. The effect of concentration polarization and fouling on flux and rejection rates as functions of time was evaluated. An approximate cost estimate for an aerobic process vis-a-vis a RO membrane process for treatment of the composite effluent is presented. Copyright © 2003 Society of Chemical Industry

Pilot-scale reverse osmosis (RO) studies were carried out to determine the feasibility of the process for treating the wastewater from a vegetable oil industry. The effect of varying feed pressure (0–69 bar) and feed TDS concentration (0.54–5.2% w/v) on separation performance of the thin film composite (TFC) polyamide RO membrane was determined. At original effluent composition and feed pressure of 55.2 bar, high rejection of TDS (99.4%) and COD (98.2%) along with complete rejection of color and BOD was achieved with a reasonably high flux of 52.5 l/(m2 h). The flux and percent rejection of pollutants improved significantly with increasing transmembrane pressure at constant feed concentration but decreased with increasing feed TDS concentration. RO was found to be very suitable for treating oil effluents having TDS concentrations upto 52215 ppm.

Microgel electrophoresis of single cells or nuclei (DNA comet assay) was investigated to identify irradiated spices. Ten spices treated with radiation doses in the range of 0 to 20 kGy were analyzed. After electrophoresis, radiation-damaged DNA appeared as a comet, whereas in nonirradiated spices round or conical spots appeared. Shape, length, and intensity of comets were also dose-dependent. Detection was successful in poppy seeds, cardamom seeds, caraway seeds, and nigella seeds, but not in pomegranate seeds, ginger root, and juniper berries, where lysis was insufficient, and also not in black peppercorns, nutmeg seed, and rosemary leaves, where extraction of cells or nuclei failed. Nevertheless, for some irradiated foods the DNA comet assay is a rapid and inexpensive screening test. L'electrophorese sur microgel de cellules ou de noyaux uniques (test de la comete) est evaluee pour identifier des epices irradiees. 10 epices traitees par des doses d'irradiation de 0 a 20 kGy sont analysees. Apres l'electrophorese, l'ADN endommage par la radiation apparait en forme de comete alors que dans les epices non traitees, des points ronds ou coniques apparaissent. Cette methode n'est pas efficace pour toutes les epices, mais elle est rapide et peu onereuse.

The fracture properties of small, cylindrical samples of endosperm machined from single kernels of several varieties of wheat were measured using three methods: compression, wedge fracture and indentation. In addition, dynamic compression tests were also performed in impact loading. Density measurements using a variable density liquid gradient were carried out on machined endosperm samples that had previously been tested for fracture properties, enabling direct comparisons between their density and fracture properties. Within each variety, a distribution of density and hardness values was found. Soft wheat varieties (Riband, Apollo) showed a broad distribution of density with medians in the range 1340 to 1395 kg/m3, whilst hard varieties such as Mercia and a durum wheat exhibited much narrower distributions and higher mean densities, Mercia being skewed towards higher densities, with a median at around 1410 kg/m3. A considerable amount of overlap in density between the soft and hard variety occurred, with both containing a significant proportion of harder and higher density wheat grains, and the major difference appearing to be the presence in the soft wheat of a large proportion of lower density endosperm in the range 1280 to 1360 kg/m3. The differences in density between endosperm samples were attributed to variations in endosperm porosity, which were correlated with the fracture properties of the endosperm. It is proposed that increased levels of porosity weaken the endosperm structure and are responsible in part for soft endosperm texture. The relationship between endosperm density and fracture properties was non-linear, the failure stress and fracture toughness increasing rapidly as the density approached a limiting value corresponding to the density expected for pore-free endosperm. This indicates that endosperm is a notch sensitive material, where the pores concentrate applied stresses and can act as sites of crack initiation. It was shown that the notch sensitivity of endosperm is qualitatively consistent with models of brittle fracture based on fracture mechanics theory, i.e. stress concentration by voids.

The main causes of nocturia, or voiding at night, are reduced bladder capacity and nocturnal polyuria. The authors discuss lifestyle changes that may help address this bothersome symptom, and outline the available treatment choices. Copyright © 2011 Wiley Interface Ltd

Cyanoacrylate glue was originally discovered by Coover and colleagues at the Kodak Research Laboratories [Tennessee] in 1942 [1] with methyl-2-cyanoacrylate becoming commercially available as ‘Eastman #910’0, later ‘Super Glue’ in 1958 [2]. Today cyanoacrylate glues such as methyl 2-cyanoacrylate, ethyl-2-cyanoacrylate (commonly sold under trade names like Super Glue and Krazy Glue – Figs. 2–4) are widely available and commonly used by the general public in domestic and industrial environments. The surgical applications of cyanoacrylate glues were suggested soon after their commercial release, in 1959 [3] and their use first reported in the literature in 1969 [4]. In 1998, 2-octyl-cyanoacrylate received United States Food and Drug Administration (FDA) approval as a tissue adhesive in skin closure. Today it is employed in most surgical specialities and being applied in novel circumstances in an ever increasing number of procedures [5–7]. Cyanoacrylate glues bond rapidly via an exothermic reaction which inevitably has the potential to cause burns. Surprisingly, given the widespread availability of cyanoacrylate glues such injuries are very rarely reported. We here present a case of an accidental burn following spillage of cyanoacrylate glue onto cotton fabric trousers.

Through the application of modern geostatistical analysis and inversion techniques drawn from contemporary seismic interpretation methods a number of 1D resistivity data have been re-modeled and visualized in 3D space. The resultant model extends the original interpretation of the data to depict alluvium layers as lithological and structural units within the bedrock. By tuning the variogram parameters used in this approach it is possible to visualize the individual lithofacies and geomorphological features in the subsurface rock units. In this study an electrical resistivity data set collected in the 1980’s as part of a groundwater study in an area of the Peshawar basin of Pakistan has been re-examined. Limited borehole log data have been combined with local outcrop information to calibrate the data. The Himalayan orogeny has uplifted and generated significant faulting in the bedrock of the area resulting in the formation of several clay-filled depressions. Paleo-streams have reworked the clays and the resultant sediments have been deposited as prograding fan shaped bodies and lacustrine deposits with inter-layered sand-gravel and clay-silt facies. The Naranji area aquifer has thus formed as a result of local tectonic activity with fluvial erosion and deposition and is characterized by coarse sediments with high electrical resistivities.

Some investigations on the preparative procedures of fibrous polyacrylonitrile thorium (IV) phosphate (PANThP) are reported. This new fibrous ion exchanger has been characterized on the basis of SEM and the ion exchange studies. The distribution studies reveal that the exchanger is highly selective for Pb(II). On this basis some useful binary separations of Pb(II) from other metal ions have been performed on its column indicating its useful environmental applications.

Crosslinked chitosan membranes were synthesized using glutaraldehyde and characterized by infra-red (IR) and wide-angle X-ray diffraction (WAXD) spectroscopic methods. The membranes were applied for the pervaporation-based dehydration of the highly hazardous and hypergolic unsymmetrical dimethylhydrazine liquid propellant. The characterization techniques were an efficient tool in identifying polymer–liquid interaction sites and the separation mechanisms involved. The crosslinked polymer was found to have good potential for the separation of the aqueous azeotrope of the propellant (20 wt%) and its enrichment to >90% purity. An equilibrium sorption study examined the preferential affinity of the membrane amongst the two penetrating liquids. The pervaporation performance of the membrane was evaluated by varying the experimental parameters of feed composition, membrane thickness and permeate pressure, and found to be promising. © 2001 Society of Chemical Industry

We extend Hardy's discrete inequality to multiple series. For an r -fold series the correct constant is ( c p ) r , where c p is the constant in Hardy's original theorem. This constant is optimum and the inequality is strict unless all variables in it are 0.

Performance of certain modified ethylcellulose (EC) membranes was investigated for the recovery of propylene from a gas mixture, having the same composition as the absorber tail gas (ATG) of a fluid catalytic cracking unit of HPCL refinery, Vishakhapatnam. The mixture contains C 1 –C 5 hydrocarbons and non-hydrocarbons such as CO, CO 2 , H 2 and N 2 . Various metals such as silver, ruthenium, palladium and iridium were incorporated into EC membranes to modify the membrane permeation properties for selectively increasing the propylene flux by facilitating its transport. Ethylcellulose membranes appeared to have good potential for the commercial recovery of propylene from a hydrocarbon rich off-gas mixture containing the olefin as a major constituent. A reasonably high selectivity of 5.1 accompanied by high transport rates was obtained for propylene with respect to propane in the multicomponent mixture. Amongst the metal-incorporated membranes, the best results were obtained with a silver (5 wt.%)-EC membrane which yielded a permeate stream of around 65 mol% propylene. The permeation of the various other hydrocarbon components present in the ATG mixture through the metal incorporated EC membranes was also analyzed. Interaction of the metal ions with the membrane matrix has been explained by characterizing the films with the help of FTIR, WAXD and SEM–EDX techniques.

Monomethylhydrazine (MMH) is a well-known liquid propellant used as fuel for launching of rockets and satellites. The desalted reaction liquor of MMH contains about 2 wt % of the propellant (balance water), which also forms an azeotrope with water at 35% MMH concentration. Removal of water to obtain pure MMH by conventional separation methods such as distillation is hazard prone and expensive. The potential of the membrane-based pervaporation technique has been investigated in this study for enriching aqueous solutions of MMH. Ethylcellulose membrane, which is selected on the basis of estimations of Flory−Huggins interaction parameters and Hansen's solubility parameter, gives promising results and is resistant to chemical attack by MMH. The effect of operating parameters such as feed concentration and membrane thickness on flux and selectivity are evaluated. Finally aging studies have been carried out to determine the life of the membrane in the propellant medium.

Adsorption thermodynamics has been studied on the beads of hybrid inorganic ion exchanger: styrene supported zirconium (IV) tungstophosphate for a pesticide phosphamidon at 30, 45 and 60°C. As a result some thermodynamic parameters like Freundlich constants, thermodynamic equilibrium constant (K0), standard free energy changes (ΔG0), standard enthalpy change (ΔH0) and standard entropy changes (ΔS0) have been evaluated.

Ethylcellulose membrane has been selected on the basis of Hansen's solubility parameter and Flory–Huggins interaction parameter for the enrichment of hydrazine and monomethylhydrazine (MMH) liquid propellants by pervaporation. An extensive study of the overall mass transfer resistance experienced by the permeants has been conducted. The resistance values were quantitatively estimated by changing the membrane thickness and calculating the corresponding flux. Due to its lower sorption, and fewer interactions, the membrane showed least desorption resistance towards water and thus it is permselective with respect to water. Results of pervaporation selectivity obtained in separation of water–hydrazine and water–MMH mixtures at azeotropic compositions have been correlated. Higher sorption of MMH and hydrazine did not result in preferential separation inspite of lower membrane resistance. Experimental results clearly showed that desorption resistance and diffusivity were predominant over the respective solubilities. To confirm the reasons for these phenomena, FTIR and DSC spectra of membranes soaked in pure hydrazine, MMH, water and hydrazine hydrate were compared.

Correlations were developed to predict total and dynamic liquid holdup in terms of drift flux model, hold up ratio, and gas and liquid Reynolds numbers for the experimental data of the present study covering air-water and air-MEA systems for three different packing and a wide range of literature data. These corelations predict the present data and most of the literature data with an RMS deviation less than 0.1. The present static liquid holdup data was found to agree with the correlation due to Saez and Carbonell (1985).

Separation of hydrazine from aqueous solutions with ethylcellulose membranes has been investigated by using the pervaporation technique. The effect of membrane thickness, concentration polarization, and feed concentration on flux and selectivity were evaluated. A separation mechanism is proposed based on the measurements of sorption, and diffusion coefficients, and estimations of Flory-Huggins interaction parameters and Hansen's solubility parameter. States of water, hydrazine, and hydrazine hydrate are explained with DSC spectra. The specific interaction sites in ethylcellulose matrix where the solvent interacts extensively with the polymer have been identified by FTIR analysis.

Membrane-based separation of olefin–paraffin mixtures and the subsequent scaling-up of the process is gaining a lot of importance in today's chemical and petrochemical industry. The performance of polymeric membranes made of poly (phenylene oxide), polysulfone, cellulose acetate and ethylcellulose was investigated for the separation of propylene from propane. Ethylcellulose was found to have good potential for recovering propylene from propane–propylene mixtures commercially. The performance of single stage permeators equipped with ethylcellulose membrane was simulated by comparing mathematical models available in literature for counter-current and cocurrent flow patterns. The derivations were cast in a form suitable for computer calculation. The permeate compositions and the membrane area requirements were determined as functions of stage cut, stage pressure ratio and feed composition. A study of multistage cascade calculation for obtaining propylene of polymer grade purity has been presented for the two flow patterns. The performances of all the membranes were simulated and compared for single stage separation for countercurrent flow pattern. Comprehensive characterisation of polymeric membranes through experimental studies was essential to suggest the most optimum configuration of commercial separation system.

Specific interaction sites of ethylcellulose (EC) with water and monomethyl hydrazine (MMH) and its hydrate have been studied by Fourier transform infrared spectra. Measurements of diffusion and sorption coefficients of MMH and water in EC were made from the reduced sorption curves to determine the overall selectivity of the membrane. Flow patterns across the membrane were examined under an optical microscope (OM) equipped with a differential interference contrast (DIC) facility. Correlation of the front velocity and the diffusivity has been used to calculate and compare these values of diffusion coefficient with that obtained from reduced sorption curve. Desorption of MMH hydrate from EC has been attributed to polymer relaxation phenomena. The physical aging process of the membrane has been monitored by FTIR analysis and mechanical strength evaluation. These studies showed that the EC membrane can be used for prolonged periods in MMH and, as such, is suitable for the separation of MMH–water solutions. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 689–700, 1999

Incorporation of a polymer material into an inorganic ion exchanger provides a class of hybrid ion exchangers with a good ion exchange capacity, high stability, reproducibility and selectivity for heavy metals. Such a type of ion exchanger ‘polyaniline Sn(IV) arsenophosphate’ has been synthesized by mixing polyaniline into inorganic material. This material is characterized using X-ray, IR, TGA studies in addition to ion exchange capacity, pH-titration, elution and distribution behaviour. On the basis of distribution studies, the material has been found to be highly selective for Pb(II). Kinetic study of exchange for the metal ions has been performed and some physical parameters such as self diffusion coefficient D0, energy Ea and entropy ΔS* of activation have been determined.

Unsymmetrical dimethylhydrazine and monomethylhydrazine are the two well-known liquid propellants. Substantial amounts of sodium chloride present in the aqueous unsymmetrical dimethylhydrazine and monomethylhydrazine reaction liquors. Pervaporation experiments have been conducted using dense chitosan membrane for desalting of these reaction liquors. The effect of membrane thickness, salt concentration in the feed, and permeate pressures on flux and % rejection have been studied and discussed to optimize the conditions. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 141–149, 1999

Studies of the states of water, hydrazine and hydrated hydrazine in ethylcellulose membrane were made for various mass fractions of solvents using differential scanning calorimetry (d.s.c.). Four or five energetically distinct states of these species in the membrane were identified and their quantitative estimations made. A new peak of enthalpy of mixing was identified at higher temperatures. Such a significant peak has not been previously recorded or discovered by d.s.c.

Tests with mixture of gases were carried out at room temperature (30±2°C) to determine selectivities and permeabilities of propylene and propane. The ideal selectivities of the membranes towards the olefin were also evaluated. Metal-incorporated poly (2,6-dimethyl-1,4-phenylene-oxide), (PPO) membrane was used for facilitating transport of the olefin through the membranes. The metals incorporated were Silver (Ag(I)), Palladium (Pd(II)), Ruthenium (Ru(III)) and Iridium (Ir(III)). PPO showed high ideal selectivities with respect to propylene. Among the metal-incorporated PPO membranes, significantly improved flux and selectivity was obtained especially for Ru(III) and Pd(II). Pd–PPO membranes exhibited two-fold improvement in propylene permeance with improved selectivity from 3.44 to 5.33. The membranes were characterised by Fourier Transform Infra Red spectroscopy (FTIR), Inductively Coupled Atomic Emission Spectroscopy (ICP-AES), Wide Angle X-ray-Diffraction (WAXD) and density measurements to understand the structural characteristics of the membrane responsible for the observed behaviour. From IR results the metals particularly Ru, Pd, Ag, Ir were found to interact with the polymer. The improved selectivity values of the metal incorporated polymers have been explained by a decrease in the effective distance ( d eff ) between the adjacent intersegmental chains due to formation of metal–ion complex with the polymer matrix and hence a decrease in the free volume of the polymer upon metal incorporation. However, the significant improvements in the propylene permeabilities have been realised mainly due to the selective transport of propylene molecules mediated by the incorporation of selected metal ions.

The solubility parameter of chitin and chitosan was determined by group contribution methods (GCM) and the values were compared with the values determined from maximum intrinsic viscosity, surface tension, the Flory-Huggins interaction parameter and dielectric constant values. The values, thus, obtained were confirmed by values obtained from GCM. The solubility parameters of chitosan determined by these methods are more or less equal and the average is approximately 41 J1/2/cm 3/2. A method for estimating the overall solubility parameter of chitosan having any degree of deacetylation is proposed.

Specific interaction sites of ethylcellulose with water, hydrazine, and the mixtures of hydrazine hydrate and water have been studied by FTIR spectra. Measurements of diffusion and sorption coefficients of these materials in ethylcellulose were made to determine the overall selectivity. Aging studies of the membrane including an accelerated aging test have also been conducted. The influence of aging on physico-chemical and mechanical properties were assessed by FTIR studies and mechanical tests. These studies showed that the ethylcellulose membrane can be used for prolonged periods in hydrazine hydrate and as such is suitable for the separation of hydrazine−water mixtures.

The kinetics of adsorption of the pesticide phosphamidon on beads of antimoy (V) phosphate cation exchanger have been studied. Physical parameters such as order of reaction, rate constant, activation energy, enthalpy of activation, entropy of activation and free energy of activation have been obtained. The adsorption behaviour is found to be second order during the first 15 min and thereafter, up to 180 min, it is first order.

The removal of ozone destroying atomic chlorine or its reservoirs by atmospheric electrical charging is reviewed for three different heights and regimes. Atmospheric electrification provides electrons which can attach to chlorine atoms of high electron affinity, inhibiting its catalytic destruction of ozone. In one scheme electrons are emitted from an isolated photocathode platform by either a closed circuit current configuration or the concurrent release of positively charged water droplets. Two other remediation schemes are described to illustrate the diversity of electrical charging. Laboratory testing can verify measuring equipment for ion composition and validate remediation concepts. It also offers a check on computer modeling. We also respond to comments ofViggiano et al. [Science 267 (1995) 82] regarding practicality of our ozone mitigation scheme.

A new analytical solution for the cumulative batch grinding equation for first-order breakage has been proposed. Knowledge of two basic parameters of attrition, the selection and breakage functions, is sufficient to solve the equation. The conservation equation of the weight fraction for different size intervals has been discretised with the maximum size as the last grid. This mode of dividing size is unlike the other methods commonly used. The advantage of this method is that not only does it involve no iterative technique but it does not rely on any approximation either. Moreover, it is computationally extremely simple and straightforward.

Reticulocyte responses to low-dose erythropoietin (EPO) were monitored using automated flow cyto-metric analysis. Sixteen adult dialysis patients were treated with 1,000 U of recombinant human EPO (rHuEPO), subcutaneously, thrice weekly (mean dose 15.7, SD 3.7 U/kg). The reticulocyte count (baseline 31.1, SD 19.1 times 109/L) increased in 14 patients in the first week, with a peak response occurring at Week 2 (mean 57.3, SD 26.5 times 109/L, p < 0.01). There was a wide spectrum of response, the maximal absolute increment ranging from 6.8–69.7 times 109/L (maximal percentage increase 19–863%), Overall there was no relationship between the early increment in reticulocyte count and hemoglobin (Hb) response over the ensuing 4 months. Nine patients became transfusion independent (mean Hb increasing from 6.9, SD 0.8–9.2, SD 1.2 g/dl). Two patients had poor reticulocyte increments and no significant change in Hb. The remaining 5 patients responded partially with a brisk reticulocyte response and a marked reduction in transfusion dependency, but without a sustained increase in Hb. On investigation, all had gastrointestinal bleeding (melena in 1, commencing after initiation of treatment, positive fecal occult bloods in 4), whereas none of the other patients showed evidence of blood loss. It is notable that the erythron was sensitive to this modest dose of rHuEPO in the majority of patients as evidenced by the reticulocyte response. The results provide useful information in the management of patients on rHuEPO. A small or inappar-ent reticulocyte response suggests a confounding factor; a poor Hb response in the presence of active reticulocyte synthesis points to occult blood loss or hemolysis.

After convectional drying, bean seeds (Nadwislanski variety) were subjected to impact trials conducted in a specially constructed centrifugal impactor. The influences of rotational speed of 1000-2500 rev/min, seed moisture content of 14-21% w.b., and drying air temperature of 25-55°C on seed damage and germination were examined. To make the results more useful, a theoretical analysis of the mechanical forces acting on the seed was conducted to determine impact velocities. Values of impact velocity, below 4·0m/s and seed moisture contents above 18% w.b. were associated with acceptable seed damage of 5%. The test conditions, within the ranges given above, had little effect on seed germination capacity.

1. The inheritance of various plumage colour variants and their underlying interactions were investigated in a large flock of Japanese quail maintained at CARI (India) by conducting reciprocal crosses between four breeding stocks inheriting Pharaoh, White Breasted, White and Brown plumages, followed by test crosses. 2. Based on the proportion of plumage-colour types in the progeny, putative genotypes were determined for parents and offspring for each of the crosses. 3. The White and Brown phenotypes were attributed to the Panda (S) and Roux (Br) loci respectively in agreement with contemporary quail stocks. 4. The White Breasted plumage type present in our stock was caused by a novel mutation with dominant gene action at an autosomal locus that was not allelic to either Panda or the White feather locus. 5. A recessive epistatic action of the Panda locus (S) on White Breasted (Wb) resulted in a White colour phenotype. 6. A novel phenotype, White Breasted-Brown was co-expressed with the Br and Wb loci. 7. It was concluded that breeding for customized feather colour phenotypes in Japanese quail using colour mutations was feasible and would be advantageous in order to overcome the limitations of legislation to protect wildlife in India.

Purified mango cationic and anionic isoperoxidases catalyse the oxidation of guaiacol, o-dianisidine and 2,2′-azino-di-3-ethyl-benzothiazoline sulphonate (ABTS) at different rates. For an anionic isoperoxidase (A1) o-dianisidine is the most susceptible substrate, whereas for a cationic isoperoxidase (C1) ABTS is oxidised more rapidly. For indoleacetic acid (IAA), mixtures of anionic isoperoxidases catalysed the oxidation at higher rates than cationic isoperoxidases relative to their peroxidase activity towards o-dianisidine. For four purified isoenzymes the greatest rate of oxidation of IAA was found for A1. For dihydroxyfumarate (DHFA), mixtures of cationic isoperoxidases catalysed the oxidation at approximately twice that observed for anionic isoperoxidases per unit of peroxidase activity. Likewise, purified mango cationic isoperoxidases (C1 and C2) oxidised DHFA at a rate three times greater than that for the anionic isoperoxidases of identical peroxidase activity towards o-dianisidine. The mango anionic peroxidases have a greater molecular mass than the cationic isoenzymes. Molecular weights determined by gel filtration of 40 000, 44 000, 22 000 and 27 000 were found for mango isoperoxidases A1, A2, C1 and C2.

Three-dimensional (3D) short fatigue crack growth behaviour in a cast magnesium alloy, Elektron 21, was studied using a combination of X-ray diffraction contrast tomography (DCT) and microtomography at the European Synchrotron Radiation Facility. A 3D map of grain shapes and crystallographic orientations was produced in a miniature fatigue specimen using DCT. A focused ion beam instrument was used to introduce small notches in selected grains. Synchrotron microtomography was used to study the evolution of fatigue cracks from these notches during interrupted in situ fatigue cycling. Stage I crack growth occurred preferentially on the basal plane of the magnesium hexagonal close packed crystal, with local crack growth rates between 4 and 40 nm cycle. Retardations in the local crack growth rate were observed in certain grains and at certain grain boundaries. The observed interactions between the crack and the polycrystalline microstructure can be explained using Schmid factors and a development of the tilt-twist model of Zhai and Wilkinson (Zhai T, Wilkinson AJ, Martin JW. Acta Mater 2000;48;4917). Copyright 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Responses of fifty varieties/lines of Gossypium hirsutum L. to three NaCl salinity levels i.e., control, 10 dS/m and 20 dS/m, were compared at seedling stage. The results revealed that increase in NaCl salinity, after 30 days growth, considerably affected the root and shoot lengths, but the effect was more pronounced on roots. Based upon absolute salt tolerance and relative salt tolerance, using root length and shoot length data, three varieties/lines i.e., NIAB 78, B 557 and MNH 522 were found to be salt tolerant, and by contrast Qalandri, MNH 147 and BP52NC63 were found to be salt sensitive. In order to confirm the selection of the tolerant and sensitive varieties/lines, it was considered to study substrate salt tolerance of the selected varieties, the uptake of Na + and K + in the leaves, and then K + /Na + ratio. The estimates of broadsense heritability of root length was high, suggesting that improvement in salinity tolerance in Gossypium hirsutum L. is possible exploiting the existing variation through selection and breeding.

Electrodialysis of aqueous solutions of acetic and nitric acids encountered in the industrial practice of deacidification of raw glyoxal solutions has been carried out to investigate the permselectivity of the system. The dependence of the permselectivity coefficient τ on experimental parameters such as flow velocity (V), current density (I), concentration of anions (Ci), etc. has been evaluated. A correlation between τ and the critical parameters has been obtained. Well-known theoretical equations have been used to calculate τ at limiting current density Ilim and as I approaches zero. Calculated results are compared with observed values. Limitations of theoretical procedures when applied to a system containing a weak acid are explained.