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The Geological and Geomorphological study in Upper Ganga basin has been attempted in parts of de Uttarkashi,Chamoli, Pauri and Tehri districts an area of 10000 Sq.kms in parts of QA sheet 53Jand 53 N on1:50000 scale of Garhwal Himalaya U.P presently known as Uttrakhand State of Union of India. Out of total area of study, an area about 3500 sq.Kms has been selected for detailed Geological, Geomorphological and Sedimentological study. The area of Upper Ganga basin consisting ofAlaknanda,Bhagirathi,Bhilangna, Nandakini, Mandakini, Pindar, Dhauli- Ganga Bal- Ganga , Madhmeshwar Ganga and Berhi Ganga The Alaknanda is chracterised by six terraces followed by Bhagirathi with five terraces , Bhilangna Nandakini four terraces Mandakini /Pindar/Dhauli-Ganga /Balganga three terraces , Madhmshwar Ganga two terracesand Bberhi Ganga one terrace,amidst theseAlaknanda is trunk stream and others are tributaries. Geomorphologically the area is divided in to seven geomorphicunitsviz High relief formerly glaciated area, Structural hills, Denudational hills, Area of mass wasting, High level dissected fans, river Terraces and Present day flood plain of Alaknanda and its tributaries . These units area developed in response to lithology to erosional land depositional activities and tectonic in which they are embedded. Each unit is characterized by drainage, diagnostic geomorphic landform elements and features, photo charcters and morphogenetic expression. The other geomorphic features and elements identified in the area are point bar, channel bar, alluvial fans ,talus cone , rock cut terracesfan cut terraces , abandoned channel ,epigenetic gorges, strand lines landslides ,rock fall scree and scree slope, retreating scarp, abandoned cirque, arêtes, threshold, horn peak and glacial lake. The area genetically comprised of terraces of three domains, viz. Glacial, Fluvio-glacia and Fluvial which represent distinct environment of sedimentation of Pleistocene, late Pleistocene and Holocene time during Quaternary period. The Glacial terraces are identified at an average elevation of 1150 m above MSL, the fluvio-glacial terraces at an average elevation of 975m above MSL and Fluvial terraces at an average elevation between 650 to 900 m above MSL. &nbsp

A review of earlier studies of the Deccan Trap occurrences of parts of Ratlam, Mandsaur, Jhabua, Dhar, Khargone, Indore, Ujjain and Shajapur districts of Madhya Pradesh, India was carried out of the area falling between latitudes 2200000 to 2400000N and longitudes 7400000 to 7600000 in Survey of India Quadrangle sheet Nos. 46I, 46J, 46M and 46N.The main objectives of the study were to synthesize the data on the Deccan Trapbasaltic lava flows , their types ,their diagnostic characteristics with special emphasis on delineating and identifying the various megacryst horizons , their levels with specific elevation above m.s.l. to build up the litho-stratigraphy for regional correlation. Broadly the area exhibits the Proterozoic Aravalli Supergroup, the Cretaceous, Bagh and Lameta Groups and the Deccan basaltic lava flows with intruded dykes and sills. The Aravalli Supergroup is represented by the Udaipur, Lunavada and Champaner Groups. The Udaipur Group consists mainly of hornblende gneiss, marble and calc-silicate, carbonaceous phyllites and chlorite schist. The Lunavada Group comprises dolomitic limestone (Phosphate bearing), quartzite, muscovite quartzite, quartz muscovite schist, feldspathised quartzite, gneissic feldspathic rock and biotitic gneiss. The Champaner Group is represented by dolomite, phyllite, slates and basic intrusives. The Aravalli Super group of rocks is also intruded by serpentinite, pyroxinite, granite and basic rocks. The Aravalli Supergroup of rocks is unconformably overlain by Cretaceous marine sedimentary deposits of Bagh Group. It includes Lower arenaceous and Upper calcareous units and occurs as discontinuous outcrops. These are almost horizontally to sub horizontally disposed. The Bagh Group is represented by three units / Formations i.e. Nimar sandstone overlain by nodular limestone and subsequently by coralline limestone. The Lameta Group of rocks is noticed in the area east and South East of Bagh exposures, overlying the Nimar sandstones. These rocks predominantly consist of limestone, gritty sandstone and conglomerate and generally exhibit hummocky topography and sometimes display solution channels. These are mostly horizontally to sub-horizontally disposed with an average thickness of 5- 6 m. The Deccan Trap has occupied a very long stretch of area which consists of a sequence of 121 basaltic lava flows with a cumulative thickness of about 610 m. These flows represent a sequence of cyclic lava eruptions with fine to medium grained a aphyric to sparsely / moderately / highly / mega porphyritic lava. About two third of the total flows exhibit Aa characters and the rest are compound and simple Pahoehoe. Some of these flows consist of megacryst units containing feldspar laths varying in size round two to five cm. These megacryst horizons have been identified at different elevations in Quadrangles 46I, J, M, N and on the basis of these horizons, various flows have been grouped into to six Formations which have specific nomenclatures and stratigraphic status. These formations are in the order of antiquity 1) Mandleshwar formation, 2) Choral formation,3) Dhar formations 4) Indore Formation 5) Bargonda Formation and 6) Singarchori Formation. Full sequence is exposed only in quadrangle 46N whereas the Quadrangles 46I, J, M do not exhibit Bargonda and Singarchori Formations. An attempt has been made to correlate the various Formations in degree sheets 46 I, J, M, N with the surroundings Geological Quadrangles. The Megacryst bearing lava- flows act as marker horizons for this purpose. A large number of dykes and dyke swamps of basaltic as well as doleritic compositions have been marked around the Narmada River. The intensity of the dykes is more in the oldest Mandleshwar Formations and it gradually decreases in increasing order of antiquity towards the younger Bargonda and Singarchori Formations. The general trend of these dykes varies from East North East – West South West to E-W running sub parallel to the Narmada lineament, besides a few dykes also cut across this lineament trend and oriented along NNW-SSE to N-S direction. The Length of these dykes varies from about 200 m to 20 Km with width varying from a few meters to as much as 200 m. The possibility exists that these dykes may have been actually feeders through which periodic eruptions of tholiitic basaltic lava took place resulting in formation of such a thick pile of lava flows. Besides as many as seven Intertrapean fossiliferous sedimentary horizons have been recognized within the basal part of the flows. These demonstrate episodic nature of volcanic activity, long periods of quiescence and resilience. The overall study of various lava flow s and their interrelations their relative dispositions thinning /swelling and pinching nature. Their relative elevations, occurrence of marker megacryst units, change in lava characters, overall gradient of lava flows and their relation to preexisting topography and slope elements reveals that the sources of lava eruptions of Older Formations are situated somewhere in the west and south west whereas those of Younger Formations are located in the Eastern part of Mhow of the area studied. &nbsp

This research study explores the effects of entropy generations on the pulsatile blood flow through a w-shape curved stenosed channel. The mathematical formulations of this physical problem are derived from the couple equations of momentum and energy. These equations are first normalized, and then solved numerically using the explicit finite difference technique. Subsequently, the solutions of these equations are utilized in the calculation of the Bejan number (Be) and entropy generations (NG). To simplify this problem, a few assumptions are taken into consideration; for instance, a mild stenotic condition is assumed in order to reduce the order of differential equations. The results are based on various velocity graphs sketched under the influence of the curvature (Rc) and magnetic (M) parameters. The magnitude of velocity as well as streamline profiles are highly affected due to the curvature effects of channel wall. The results demonstrate that the value of Bejan (Be) number is highly influenced by increasing the value of curvature parameter (Rc) as depicted in the graphs. Similarly, the shape of velocity profile reduces to symmetric in the unbent vessel. Moreover, it is also observed that the magnitude of velocity has decelerated in the presence of magnetic field.

For ambient radio-frequency (RF) energy harvesting, the available power levels are quite low, and it is highly desirable that the rectifying diodes do not consume any power at all. Contrary to semiconducting diodes, a tunnelling diode – also known as a metal-insulator-metal (MIM) diode – can provide zero-bias rectification, provided the two metals have different work functions. This could result in a complete passive rectenna system. Despite great potential, MIM diodes have not been investigated much in the GHz-frequency regime due to challenging nano-fabrication requirements. In this work, we investigate zero-bias MIM diodes for RF energy-harvesting applications. We studied the surface roughness issue for the bottom metal of the MIM diode for various deposition techniques such as sputtering, atomic layer deposition (ALD) and electron-beam (e-beam) evaporation for crystalline metals as well as for an amorphous alloy, namely ZrCuAlNi. A surface roughness of sub-1 nm has been achieved for both the crystalline metals as well as the amorphous alloy, which is vital for the reliable operation of the MIM diode. An MIM diode comprising of a Ti-ZnO-Pt combination yields a zero-bias responsivity of 0.25 V− 1 and a dynamic resistance of 1200 Ω. Complete RF characterisation has been performed by integrating the MIM diode with a coplanar waveguide transmission line. The input impedance varies from 100 Ω to 50 Ω in the frequency range of between 2 GHz and 10 GHz, which can be easily matched to typical antenna impedances in this frequency range. Finally, a rectified DC voltage of 4.7 mV is obtained for an incoming RF power of 0.4 W at zero bias. These preliminary results of zero-bias rectification indicate that complete, passive rectennas (a rectifier and antenna combination) are feasible with further optimisation of MIM devices.

This paper reports the synthesis of polypyrrole–titanium(IV)phosphate (PPy–TiP) nanocomposite as a synthetic adsorbent for the adsorptive removal of Cr(VI) ions from aqueous solutions. Facile in situ chemical oxidative polymerization of pyrrole in presence of titanium(IV)phosphate (TiP) formed PPy–TiP nanocomposite. The prepared PPy–TiP nanocomposite was characterized by FT-IR, FE-SEM, TEM, EDAX and BET analysis. A strong interaction between PPy and TiP particles was observed, and the nanocomposite showed remarkable adsorption of Cr(VI) ions from aqueous solutions. In order to optimize the conditions for maximum adsorption of Cr(VI) ions, batch process was used and the effects of contact time, initial concentration, pH, point of zero charge measurement and adsorbent doses were investigated. The equilibrium isotherm data were fitted using Langmuir and Freundlich isotherms. The adsorption process based on the thermodynamic parameters was spontaneous and endothermic. Dubinin–Radushkevich (D–R) isotherm was used to calculate the mean free energy, which showed that the adsorption process involves chemical forces, hence chemical in nature. The kinetics data were evaluated using the pseudo-first-order and pseudo-second order kinetics model, and it was found that data was best fitted by the pseudo-second-order model for adsorption of Cr(VI) supporting that the adsorption mainly consisted of chemisorption. The desorption studies were also performed by batch process and ∼100% desorption of Cr(VI) ions was achieved using 0.5 M NaOH solution as eluent.

Twenty five spring wheat genotypes were evaluated for terminal heat stress tolerance in field environments in the Agro Ecological Zone-11 of Bangladesh, during 2009-2010 cropping season. The experiments were conducted at Wheat Research Centre, Bangladesh Agricultural Research Institute, using randomized block design with three replicates under non-stress (optimum sowing) and stress (late sowing) conditions. Seven selection indices for stress tolerance including mean productivity (MP), geometric mean productivity (GMP), tolerance (TOL), yield index (YI), yield stability index (YSI), stress tolerance index (STI) and stress susceptibility index (SSI) were calculated based on grain yield of wheat under optimum and late sowing conditions. The results revealed significant variations due to genotypes for all characters in two sowing conditions. Principal component analysis revealed that the first PCA explained 0.64 of the variation with MP, GMP, YI and STI. Using MP, GMP, YI and STI, the genotypes G-05 and G-22 were found to be the best genotypes with relatively high yield and suitable for both optimum and late heat stressed conditions. The indices SSI, YSI and TOL could be useful parameters in discriminating the tolerant genotypes (G-12, G-13, and G-14) that might be recommended for heat stressed conditions. It is also concluded from the present studies that biomass, grain filling rate and spikes number m-2 are suitable for selecting the best genotypes under optimum and late sowing conditions because these parameters are highly correlated with MP, GMP, YI and STI. However, high ground cover with long pre heading stage and having high grain filling rate would made a genotype tolerant to late heat to attain a high grain yield in wheat.

Zinc hexacyanoferrate nanocubes have been synthesized following an extremely simple method and characterized by elemental analysis, thermal analysis, infrared spectroscopic and X-ray diffraction techniques. Field emission scanning electron microscopic image showed that it consisted of sharp cubic particles with size ranging from 83 to 164 nm. Catalytic activity of nanocubic zinc hexacyanoferrate has been studied for solvent-free oxidation of benzyl alcohol using H 2 O 2 as oxidant under the optimum conditions of certain parameters such as benzyl alcohol to H 2 O 2 molar ratio, the amount of catalyst, reaction time and temperature.

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.

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.

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.

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.

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

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.

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.

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.

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.

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.

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 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.