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Lately, coated steel sheets have replaced bare steel in the automotive sectors due to their corrosion protection. Among them, zinc-coated high strength interstitial free (HIF) steel is widely used due to its durability, formability, good surface finish, impact resistance, and corrosion resistance. However, joining galvannealed (GA) steel using conventional fusion welding processes is challenging as it results in porosity and potentially harmful fumes. To overcome these challenges, this work uses a pulse MIG (metal inert gas) brazing technique to join the HIF-GA steel sheet with a lap joint configuration utilizing Cu-Si base filler wire (CuSi3Mn1) in an argon atmosphere. The study aims to evaluate the effect of heat input on bead geometry and Zn degradation in MIG brazed joints by adjusting the current from 40 to 60 A and brazing speed from 400 to 500 mm min−1. It is observed that the heat input is inversely proportional to the wetting angle and directly proportional to the bead width, leg length, and cross-sectional area. Heat input influences Zn degradation on both the front (at the toe) and back sides of the lap joint. The corrosion behavior of joints is studied using an electrochemical test (in 3.5% NaCl solution) and a salt spray test (in 5% NaCl solution). Further, the Zn degradation is analyzed with EDS line scanning to understand the corrosion resistance of the MIG brazed joints. A potentiostatic polarization study is also conducted to determine the corrosion rate using a Tafel plot. It is found that the lowest corrosion rate in base metal (BM) increased from 0.88 to 12.26 mm year−1with the increase in heat input from 61 to 113 J mm−1.

This article refers to an investigation of peristaltic transport of hybrid nanoparticle suspended blood through an endoscopic annulus with elastic walls in the existence of blood clotting under electromagnetic forces (EMF). The dual effects of Hall and ion-slip currents are accounted for. The energy equation is formulated invoking internal heat source and viscous-Ohmic dissipation terms. Blood is used as a base fluid, and silver and aluminum oxide nanoparticles are dispersed in order to have a hybrid blood suspension. The impacts of the geometrical shape of nanoparticles are examined. The governing partial differential equations (PDEs) for the proposed flow model are simplified under the assumption of long wavelength and low Reynolds number. The transformed non-linear coupled PDEs are solved analytically by employing the homotopy perturbation method (HPM) with Mathematica computational software. The graphical illustrations are presented to interpret various flow constraints of interest. Outcomes reflect that the Hall and ion slip parameters have diminishing behavior on the blood flow while the opposite fashion prevails on it for increasing Hartmann number. Augmenting Hall and ion slip parameters result in an upsurge in the blood temperature. Expanding the volume fraction of nanoparticles enhances the blood temperature. Hall and ion slip effects are to reduce the wall shear stress (WSS) at the peristaltic wall. The maximum amplitude of the heat transfer coefficient is computed for the brick shape of nanoparticles when compared to the other shapes of nanoparticles. The streamlines are configured with trapping ed bolus phenomena to outline the blood flow pattern in the endoscope. Our model may be pertinent to physiological systems, medical simulation devices, transport phenomena in pharmacology, nano-pharmacological delivery systems, surgical procedures, etc. In endoscopy, a magnetic force field is used in order to detect or treat diseases.

Uncertainty analysis of groundwater flow and solute transport model is important from the point of safety measures in the field of nuclear science and technology. Researchers have already carried out this uncertainty analysis using traditional Monte Carlo simulations. However, in practice, Monte Carlo simulation may not be possible because of lack of data obtained from the field experiments. Therefore, demand is to investigate the uncertainty by using imprecise based method. In order to fulfill this demand, we have carried out the parametric uncertainty analysis of solute transport model using a fuzzy set method. This paper, proposes an innovative methodology for solving advection diffusion equation describing tracer transport through geological media in presence of imprecise measurements of model parameters such as tracer dispersion coefficient and groundwater flow velocity. Measurement around most likely value provides a spread causing an imprecision of the model parameters. Imprecision is addressed as a fuzzy variable and the membership function of each such fuzzy variable is expressed in the form of a triangular fuzzy number. The governing advection dispersion equation is numerically solved using lattice Boltzmann scheme along with fuzzy parameters of the representative model and due to this the present numerical approach is named as fuzzy lattice Boltzmann. Uncertainty quantification of the solute concentration as solution of the governing fuzzy differential equation is carried out and by using this uncertainty modeling, advantage of the fuzzy lattice Boltzmann approach for obtaining the numerical solution of a fuzzy partial differential equation is shown.

Uncertainty analysis of solute transport model is an essential component for decision-making problem in the regulatory framework for safe discharge of liquid effluent in environment. Performance assessment of any industry is based on the violation of discharge limit stipulated on yearly basis by any regulatory body. Very often, regulatory bodies provide deterministic (point) solution of the solute concentration as limit of discharge which is derived using the closed-form solution. However, uncertainty of the model parameters of the governing advection dispersion equation with specific initial and field boundary conditions restricts user to obtain deterministic or closed-form solution of the solute transport model. This necessitates the numerical solution of the solute-transport model to fulfill the task of uncertainty quantification. The present paper proposes an innovative numerical method of solving solute-transport model in the presence of imprecise uncertain input parameters such as dispersivity and velocity of flow. Dispersivity and velocity of flow, both being measurable field parameters, generally posses an epistemic behavior, that is, imprecise. Therefore, uncertainty of these parameters is taken into account as triangular fuzzy number for its simplicity. Solute transport equation with these fuzzy (uncertain) parameters is numerically solved using differential quadrature method and fuzzy vertex method. Therefore, the present version of uncertainty modeling is named as fuzzy differential quadrature scheme of uncertainty modeling. The paper discusses the details of the differential quadrature method and fuzzy vertex method. The stability of the newly developed methodology of uncertainty modeling is assessed by comparing the numerical solution with possible analytical solution.

The source of geogenic arsenic (As) contaminating a shallow aquifer in West Bengal was traced to fine‐grained sediments deposited in an abandoned river channel. Along with As‐bearing phases, these sediments contain 0.46% codeposited organic carbon. The release of As and the geochemistry of groundwater within the channel‐fill deposits is investigated using a detailed mass balance model supported by aqueous, solid‐phase, and mineralogical data. The model describes the evolution of groundwater chemistry along a flow path extending from its recharge in an abandoned channel pond, through the channel fill, to the underlying aquifer. Variations in groundwater composition are explained in terms of mineral weathering of host sediments driven by organic carbon decay. Arsenic is released through the reductive dissolution of goethite and the weathering of chlorite. Concomitantly, some As is sequestered in precipitating vivianite. These competing processes reach equilibrium deeper in the channel‐fill sequence as groundwater As concentrations stabilize. The model yields estimates of mineral reaction (or precipitation) rates including rates of organic carbon oxidation (1.15 mmol C L−1a−1) and net As release ( 4.57×10−4mmol L−1a−1). Fine‐grained, slightly permeable, deposits such as channel fill containing reactive organic carbon and As‐bearing goethite and phyllosilicates are centers of intense chemical weathering conducive to As mobilization. Groundwater contamination by geogenic arsenic is impacting the health of over 100 million people across Asia. According to the World Health Organization, this is the largest mass poisoning in history. To advance understanding of the arsenic source and fundamental processes involved in its release, scientists from the Geological Surveys of Canada and India, and the University of British Columbia, undertook a joint research project in an affected village of West Bengal. This paper describes the geochemical evolution of groundwater as it flows through arsenic source sediments deposited in an abandoned river meander. A mass balance model was developed to explain groundwater composition and arsenic release in terms of the dissolution or precipitation of minerals found in the sediments. This study has yielded new knowledge of arsenic hosts and release processes, and it represents an important step toward the development of sound public health mitigation schemes in India and elsewhere. Chemical weathering of goethite and chlorite in channel‐fill silts releases AsSome released As is resequestered in precipitating vivianiteThe net arsenic release rate from source sediments is 34 μg L−1a−1

The work attempted to develop coated electrodes based on the microstructural design to improve the ballistic performance of weld metals of high strength armour steel. In the present investigation, three different types of coated electrodes were developed by systematic variations of flux composition starting with basic flux and addition of different ferroalloys in the electrode coating to obtain weld deposits with a microstructure predominantly martensite, bainite, and some retained austenite. Finally, butt joints were made using three developed electrodes and microstructures of the weld metals were exclusively characterized using optical microscopy, SEM, TEM and XRD along with nonmetallic inclusions study. It was observed that different types of electrodes mainly varied in the carbon content of the weld metals and with increasing carbon content of the weld metal, more martensite (71.29 %) with retained austenite (4.7 %) and less bainite (24.01 %) were observed.

Multi-material fabrication such as joining of steel and aluminium has become prominent now-a-days in automotive industries. Friction stir welding being a novel solid state welding process, has already established good joint strength between steel and aluminium; but fatigue strength of such dissimilar joint has not yet been explored. In the present study, the friction stir lap welding was performed at each rotation speed of 500, 1000, 1500 for two different travel speed i.e. 50 and 100 mm min−1at a constant probe depth of 2.5 mm. Among the six different joints, joint strength achieved of maximum (5 kN) and minimum (2 kN) under two parameter combination i.e. 1000 rpm 50 mm min−1and 500 rpm 100 mm min−1respectively, have been exclusively characterized by high cycle fatigue at R ratio 0.1. Furthermore, R ratio has been varied from +0.5, +0.3 to −0.5, −0.3 at a particular load amplitude which shows the endurance limit (106cycles) for both combination of parameters. The experimental results show that fatigue strength at 106cycles for both the FS welded lap joint is about 20 % of their respective failure load. Thus better fatigue strength is associated with the lap joint performed with the joint of maximum load. The fatigue behaviour of two FS joints has been correlated with the thickness of intermetallic compound and accumulation of dislocations observed by TEM.

AbstractBrachypeplus riangsp. nov. is described from Tripura state in India, bringing the total number of Indian species of the genus to two. The genus is re-described with detailed characterisation of different body parts including mouth parts and genitalia. The status of Brachypeplus omalinusMurray 1864 is examined.

DP590 steel sheets were joined by friction stir spot welding using polycrystalline cubic boron nitride tool with an objective to produce bond diameters similar to conventional spot welding nuggets. A range of spindle rotation (400–2400 rev min−1) and plunge speeds (0·03–3·8 mm s−1) were exercised to attain defect free welds in 1·6 mm thick sheets. A bond diameter of 4t1/2, alike minimum nugget diameter criteria for resistance spot welds, resulted in superior mechanical properties than conventional spot welds. The heat inputs corresponding to different welding parameters influenced the weld microstructure, including grain size, phases and their morphology. The bond diameter was higher for higher heat inputs. However, low heat input welds with weld time cycles ∼4 s produced more refined microstructure and exhibited similar strengths even with reduced bond size. Plug type failure was associated with larger bond diameters (∼7·1 mm), while interfacial failure was observed with smaller welds (∼5·4 mm).

A digital X-ray radiography methodology is proposed for quality assessment of aluminium–zinc coated steel dissimilar lap joints produced by a friction stir welding process. This methodology uses digital frame integration for acquisition of data to reduce the image noise followed by high pass filtering to sharpen the image by gradient operation and contrast adjustments to detect micro defects in FSW joints. The effect of welding parameters such as rotational and travel speed of weld tool and penetration depth on quality of the weld is studied. The new methodology has resulted in three-fold increase in signal-to-noise ratio (SNR) with improved defect detection sensitivity. The present study clearly shows that the weld tool rotational speed, travel speed and plunger depth have a decisive role on the quality of the weld obtained by the friction stir welding process.

Use of multimaterial fabrication such as aluminium to steel to reduce overall vehicular body weight has gained significant attention in the automotive industries. Since fusion welding of aluminium to steel is difficult, friction stir welding of the same is considered as an effective recourse. Quantitative studies on friction stir welding of aluminium to steel are thus important but scarce in the literature. We present here a numerical and experimental study on friction stir lap welding of AA6061 to high strength interstitial free coated steel sheets under different combinations of tool rotational speed and welding speed. The computed values of thermal cycle, torque and traverse force are found to be in good agreement with the corresponding experimentally measured values. The computed thermal cycles along the AA6061 to steel interfaces are related qualitatively with the experimentally measured trend and distribution in Fe–Al intermetallics along the weld joint interface.

In recent years, weld cladding are being applied in numerous industries as cost effective engineering solution to use a surface protection layer to protect carbon steel against corrosion attack. The desirable characteristics of cladding alloy are reasonable strength, weldability, resistance to general and localized corrosion attack. The duplex stainless steel having all the desirable characteristic is the candidate material for cladding. However, duplex weld metals have not been studied in detail as duplex stainless steels. Consequently, the properties of duplex weld metals are less well known and only partially understood. In the present study, the properties of duplex weld deposits of the 22 % Cr, 10 % Ni, 3 % Mo, and 0.12 % N type using GMAW process have been investigated. In particular, the influence of welding heat input and shielding gas composition in GMAW process on weld deposit microstructure, impact toughness and resistance to pitting corrosion have been studied. It is observed that concentration of nitrogen of weld deposits influenced by both heat input and shielding gas composition exerted significant effect on microstructure, low temperature toughness and resistance to pitting corrosion.

The mechanism and kinetics of the transient liquid phase diffusion bonding process in a 6061–15 wt-SiCp composite at 570°C, 0·2 MPa, with 200 µm thick copper foil interlayer, has been investigated by microstructural characterisation of the bond region using optical microscopy, scanning electron microscopy and electron probe microanalysis. The kinetics of isothermal solidification, representing the displacement of the solid/liquid interface y(in micrometres) as a function of time t(in seconds), followed a power law relationship y?=?157t0·07. According to this kinetic equation, the effective diffusivity of copper in the composite system was found to be ~106times higher than the lattice diffusivity, indicating the dominance of short circuit diffusion through the defect rich particle/matrix interface.

Abstract: Breithauptite (NiSb), a rare antimonide, is generally found associated with hydrothermal vein ores of Ni and Co. In India, it has so far been recorded only from the gold-quartz veins of the Kolar Gold Field. Occurrence of this antimonide in a sediment-hosted milieu however, has seldom been noted. We report here the identification and characterization of this rare phase in both the stratiform and the vein-type ores of the sediment-hosted Zn-Pb sulphide deposits and prospects within the Dariba-Rajpura-Bethumni metallogenic belt in Northwestern India. Metamorphic remobilization from the stratiform ores of the belt has been postulated as a possible mechanism for the conspicuous segregation of breithauptite as a discrete phase within these ores.

In this paper a convenient route for synthesizing Aucore−Pdshell bimetallic nanoparticles in toluene has been reported as a result of co-reduction of gold(III) and palladium(II) precursors in toluene. N,N-Dimethyldodecylamine was used as a capping agent for the core−shell particles, which not only imparts stability to the organosol but also controls morphology of the evolved particles. The particles were characterized using UV−visible, transmission electron microscopy, and X-ray diffraction measurements. All results substantiate the formation of core−shell structure of the synthesized particles.

The immobilization of gold nanoparticles in anion exchange resin and their quantitative retrieval by means of a cationic surfactant, cetylpyridinium chloride, is studied. The resin-bound gold nanoparticles (R−Au) have been used successfully as a solid-phase catalyst for the reduction of 4-nitrophenol by sodium borohydride. At the end of the reaction, the solid matrix remains activated and separated from the product. The recycling of catalyst particles after the quantitative reduction of 4-nitrophenol and the recovery of gold nanoparticles with unaffected particle morphology from the resin-bound gold nanoparticle entity have been reported.

A new fluorescent probe, methylamino derivative of pyrene, has been considered to characterize the concentration dependent emission behavior of an aqueous solution of anionic surfactants, viz., SDS, DSS, and SDBS. It was found that the emission of the probe is uniquely sensitive to the changes in surfactant (anionic) concentration due to the functional group effect of the probe over the parent moiety, pyrene. Here, 1-methylaminopyrene (MAP) showed significant quenching of emission well below the critical micellar concentration (cmc) of the surfactant. Excimer emission of the probe due to the formation of premicellar aggregates of the surfactant solutions at a concentration close to but below the cmc and again an enhanced emission of the probe above the cmc were observed as a consequence of definite MAP−surfactant interactions. These observations assisted the possible quantification of surfactant concentrations and their chain length dependent premicellar aggregate formations. Significant monomer emission in relation to probe distribution in micelle was analytically authenticated. Dynamic light scattering (DLS) studies revealed the incorporation of the probe molecules in the micellar core. The fluorophore emission showed nonlinear behavior when the surfactant concentration was far above the cmc. Abrupt changes in the emission characteristics in relation to the micellar concentration led to the determination of the cmc of the surfactants.

A prediction model has been developed for submerged arc weld-metal chemical composition in terms of flux ingredients with the help of statistical experiments for mixture (extreme vertices design). Bead-on-plate weld deposits as per statistical mixture design experiments were performed at the following welding parameters: current (400 A), voltage (26 V), speed (4.65 mm/s) and electrode extension (30 mm) using CaO–MgO–CaF2–Al2O3 flux system. The results show that some of the individual flux ingredients and their binary mixtures have a predominant effect on weld-metal oxygen, manganese, silicon, sulphur, nickel and carbon content. The predicted results show a reasonably good agreement with the experimental results, which were obtained by performing the actual experiments based on a randomly designed flux. Analysis of the experimental data indicate that several mechanisms such as basicity index, oxygen potential, oxide stability, viscosity, electrode chemical reaction, kinetics of slag–metal reaction, etc. are operating simultaneously to yield the final weld-metal composition.

Evolution of exclusively spherical tiny gold nanoparticle aggregates is reported by UV photoactivation of aqueous HAuCl4 solution in cetyltrimethylammonium chloride micelles. In the photoactivation process, citrate is introduced for the first time to obtain aggregates of interacting particles with a tight size distribution. It is seen that the spectrum is substantially altered from the usual Au plasma resonance while the particles are present in the aggregate. Due to the interparticle interaction, the solution renders a blue color. Blue−pink color transformation of the gold sol has been observed in relation to the change in the interparticle distances without any change in the aspect ratio of the particles.

A room-temperature wet chemical method of synthesis for sphere- and rod-shaped magnetic “solid solution” type Ni−Pt nanoparticles in cetyltrimethylammonium bromide (CTAB) micelle is reported. The particles have been found to be moderately monodispersed without adopting any further size-selection procedure. The composition of the alloy becomes tunable through adjustment of the ratio of the reactants. The temperature-dependent magnetic property, size distribution, and percentage composition of the alloyed structures are characterized by SQUID magnetometer, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and electron dispersive X-ray (EDX) analyses. The preferential evolution of nanorods over spherical particles in higher surfactant concentrations and the coalescence of the magnetic particles have been examined.

Single crystals of nonlinear optical material l-arginine acetate (LAA) (C6H14N4O2·CH3COOH), space group P21, were successfully grown for the first time by the temperature-lowering method and also by the slow evaporation method at constant temperature (30 °C) from its aqueous solution with pH at 6 and dimension of 21 × 15 × 3 mm³. Initially, solubility tests were carried out for four solvents such as water, water and methanol, water and ethanol, and water and acetone. Among the four solvents, the solubility of LAA was found to be the highest in water, so crystallization of LAA was done from its aqueous solution. Morphological analysis reveals that the crystal is a polyhedron with 16 developed faces with major face forms {100}, {001}, and {102} (pinacoids) parallel to the polar axis. As grown crystals were characterized by chemical analysis, density measurement, and X-ray powder diffraction studies. Infrared spectroscopy, thermogravimetric analysis, and differential thermal analysis measurements were performed to study the molecular vibration and thermal behavior of LAA crystals. Thermal analysis does not show any structural phase transition.

In anionic micelles, SDS has been found to remove the kinetic barrier for the reaction between methylene blue (MB) and arsine. The color bleaching (reduction) of SDS micelle bound MB by arsine gives a quantitative measure of arsenic concentration in the sub-parts-per-million levels for a test sample. Arsine is generated by reacting NaBH4 with arsenic-containing samples present along with the other reagents. The extent of the micelle-bound dye reduction is facilitated in the presence of Ag or Au nanoparticles. The micelles, in turn, help to increase the collision probability between the dye and arsine, whereas nanoparticles help the electron relay from AsH3 to the micelle-bound dye. This method depicts for the first time a simple, reproducible way to demonstrate nanoparticle-catalyzed dye reduction by arsine in an organized medium.

Formation of stable gold nanoparticles of different size and shape has been reported via UV photoactivation of HAuCl4 in variable concentrations of TX-100. It has been shown that smaller particles of gold preferentially dissolved by cyanide at a faster rate in air in comparison to that for the larger particles because of higher mobility and possibly because of lower redox potentials of the smaller particles. It is observed that smaller gold nanoparticles preferentially coalesce together at higher temperature in micelles. Temperature induced changes in the shape of the micelle provide the required template/capping condition for linear growth of gold nanoparticles.

Detergent‐grade zeolite 4A has been synthesized from the clays found in various parts of India. The process parameters for the synthesis of detergent‐grade zeolite, like the activation temperature for the chemical transformation of clay, the composition of the reacting mixture and finally the crystallization temperature, have been studied. Better metakaolinite formation has been observed at a calcination temperature of around 550 °C. The characterization of the synthesized zeolite by X‐ray diffraction study confirms its formation. Moreover, the calcium binding capacity 170 mg of CaO/gm as well as particle size in the range of 3–7 microns of this zeolite are found to be satisfactory characteristics to substitute phosphate in detergents.

In this work we have addressed the gold particle catalyzed eosin reduction in the presence of NaBH4. The catalytic activity of the gold nanoparticles is different for different size regimes (size domain dependent) of the particles. It has been shown that the kinetics of the catalytic rate has a bearing with the particle size (viz., surface area, mass, etc.). The kinetics of catalytic reduction revealed that for the same surface area of different particles, the catalytic rate does not increase proportionately with the decrease in size over the whole range of average diameter from 10 to 46 nm. The rate decreases first with the increase in particle size, and above 15 nm, it increases. Moreover, if the mass effect is also taken into account, that is, catalytic rate is determined in terms of per unit mass per unit surface area, then the resulting catalytic rate falls with the rise in particle size over the whole range of size studied. However, the rate was different for the two regimes. Photochemically prepared seed in conjunction with noniterative growth method was used for producing the catalyst particles of desired size. The small seed particles were produced by the UV irradiation of Au(III) ions present in aqueous Triton X-100 medium. The particles have been characterized by UV−visible spectrophotometric and TEM studies. Almost spherical and nearly monodispersed gold nanoparticles were obtained by this method.

Bimetallic gold and silver particles, a core−shell type structure, have been prepared by a UV-photoactivation technique. The optical absorption spectra are recorded and compared with various absorption profiles due to Au−Ag particles described in the literature. Initially Au particles formed by UV irradiation, which act as the seed particles, catalyzed the reduction of added silver ion in the presence of UV light to yield bimetallic (Aucore−Agshell) particles. Preferential dissolution of Au particles by cyanide and TEM images of the particles corroborates the “core−shell” type configuration.

Organic molecules containing a fluorophore−spacer−receptor (F−S−R) combination are a hot topic of contemporary research due to their wide applicability in information processing devices. This work is the first report of the use of metal ions and nanoparticles of coinage metals (Cu, Ag, Au) and platinum metals (Ni, Pt, Pd) in developing molecular photonic switches. In the presence of these metals, the photoinduced electron transfer (PET) normally responsible for fluorescence quenching of F−S−R molecules is hindered. These metal ions and their corresponding nanoparticles interact with the receptor (R) site, preventing its participation in PET, thus increasing the fluorescence of the F−S−R molecule. This is comparable to the “switching-on” operation of a light switch. However, beyond a certain critical concentration that varies from metal to metal, the quenching effect of the ions overrules their fluorescence enhancement (FE) effect and thus the fluorescence of the probe decreases. This is equivalent to the “switching-off” operation of a switch. Thus, digital instruments operating with the 1 (on) or 0 (off) principle can employ such metal ion/nanoparticle-probe combinations as efficient molecular photonic switches. Maintaining the critical concentration as a borderline, such systems can efficiently function as OR logic gates.

Dye reduction catalyzed by palladium nanoparticles has been investigated in water and surfactant media. The initial rate of dye reduction strongly depends on the nature of the reducing agent and dye. In most cases the rate becomes surface controlled and depends on the E1/2 values of the dye and the reducing agent. However, stronger reducing agents make the reduction process a diffusion controlled one. A detailed study has been carried out to understand the effect of surfactant on the reaction rate. A variation of the reaction rates has been observed in surfactants above and below the critical micelle concentration (cmc). Below the cmc, surfactants are adsorbed onto the Pd surface and act as a binding site for both the dye and the reducing agent. Above the cmc, surfactants form micelles which provide additional binding sites. Catalytic selectivity was also achieved by proper selection of reducing agent and surfactant.

Pharmacologically active compounds having poor permeability through several physiological barriers often limits their application. New age therapeutics such as peptides or nucleic acid-based agents are promising but their targeted delivery to the brain is challenging through conventional drug delivery methods. The objective of using carbon nano onions is to develop potential nanoscale carriers for effective diagnosis and targeted therapies. Pharmacokinetic and pharmacodynamic profiles of such nanocarriers can also be controlled, enhancing the drug concentration at target sites.This review critically evaluates the current status of the carbon nano onion mediated targeted delivery of the drugs through nasal pathway bypassing the biological barriers.This intranasal drug delivery system can escape the first-pass metabolism, increases the bioavailability of the drug to the targeted area reduces the dose of chemotherapeutic reagents having serious side effects.

Hereditary non-polyposis colorectal cancer (HNPCC) is an autosomal dominant condition predisposing to cancers of the colorectum and endometrium. Endometrial cancer is the most commonly occurring extracolonic cancer in HNPCC. Estimates of the cumulative incidence of endometrial cancer in women with mutations in the HNPCC genes range from 22-43%. In order to determine how frequently double primary cancers of the colorectum and endometrium are the result of a hereditary factor, we conducted a registry based study in Ontario and Quebec, Canada. We obtained pedigrees on 80 women diagnosed with double primary cancers of the colorectum and endometrium at less than 70 years of age. Family histories of cancer were obtained for all first degree relatives of these women and cancer rates were compared with age standardised provincial incidence rates in order to estimate the relative risks. There was a total of 82 cancers observed in relatives below the age of 55, compared with 31.2 expected, giving a relative risk of 2.6 (95% confidence interval (CI) 2.1-3.3). The relative risk for colorectal cancer below 55 was 16.1 (95% CI 11.6-21.8). This risk decreased with increasing age of onset of cancers in probands. For probands with both colorectal and endometrial cancer diagnosed under the age of 55, the relative risk of colorectal cancer in relatives below the age of 55 was 30.5 (95% CI 18.8-46.6). Similar patterns were observed for endometrial and pancreatic cancer. There were non-significant increases in rates of cancer of the oesophagus, stomach, small intestine, and bladder. There was no increased risk of breast cancer. The risk of lung cancer was decreased, especially in older relatives. Our findings indicate the presence of a significant genetic component of cancer in women with double primary cancers of the colorectum and endometrium.

The redox catalytic property of still-growing and final particles of palladium has been investigated using methylene blue (MB) and fluorescein (F) as redox probes. Reductions of MB by N2H4 and of F by NaBH4 were observed to be catalyzed by both the still-growing and the final Pd particles. In most cases the catalytic rate increases exponentially with the increase in catalyst precursor ion concentration, that is, [Pd^II] and [N2H4/NaBH4]. However, with the increase in [dye], the rate decreases in most cases, and this effect is more prominent for still-growing particles than final particles. The study shows that particle size has a significant role in influencing the catalytic property of the metal. Still-growing particles are smaller in size and render more catalytic activity provided they are sufficiently stable and their surface is not poisoned by the chemisorption of reactants or any other foreign ions/molecules. Palladized charcoal has been observed to be a much weaker catalyst than the two studied here because of its larger particle size and carbon-covered surface. An ion-exchange mechanism is proposed to explain the catalytic rate. The dye and the reducing agent are in equilibrium between the catalyst surface and bulk water. Thus, the rate of dye reduction depends on the surface concentration of dye and reducing agent.

Growing small particles of silver have been observed to be more efficient catalysts than stable colloidal particles. These growing particles catalyze the borohydride reduction of several organic dyes. The rate of the reduction catalyzed by growing particles is distinctly faster compared to that of stable and larger silver particles, which are the final products of growing particles. Catalysis is due to efficient particle-mediated electron transfer from the BH4^- ion to the dye. The catalytic activity of the particles depends on their size, E1/2 of the dye, and the dye−particle interaction. The presence of surfactant influences the catalytic property of the particles by controlling their growth, by inhibiting adsorption of reactants/products onto the particle surface, and by specific dye−surfactant interaction.

Results on the production cross sections ofW andZ bosons detected in the UA2 experiment are given based on a large sample ofW→eν andZ→e+e− decays. The measured cross sections are σWe = 660±15(stat)±37(syst)pb, σZe = 70.4±5.5(stat)±4.0(syst)pb and their ratioR=9.38−0.72+0.82(stat)±0.25(syst). In the framework of the Standard Model, the measured value ofR is used to determine the total width of theW, Γ(W)=2.30±0.19(stat)±0.06(syst) GeV.

Kinetics and thermodynamic parameters of Cr6+ separation by fly ash from aqueous solution has been evaluated. It was found that the separation process is partly diffusion controlled and endothermic in nature. The mass transfer coefficient increases with an increase in temperature. The activation energy and change of enthalpy were also evaluated and found to be 17.5 kJ/mol and 14.47 kcal/mol, respectively. The free energy of the process was small but positive, and it decreases with an increase of temperature. The change of entropy was found to be small and remains unchanged over the 30 to 50°C temperature range. This process follows the Langmuir isotherm model where Qo and b were also determined at different temperatures.

Hexavalent chromium has been separated from an aqueous solution by fly ash. The particle size distribution and physical properties of fly ash have been illustrated. It is observed that the percent removal of Cr6 + by fly ash is affected by its concentration in aqueous solution, temperature, particle size, and pH. Better separation is obtained at acidic pH and at higher temperature. Particle size has a nonsignificant effect on separation. The reaction kinetics of separation follows first-order kinetics more satisfactorily at higher temperature.