Adsorption of Ni(SO4) on Malaysian rubber-wood ash

The possible use of wood ash as an adsorbent of nickel sulphate from dilute solutions and the effect of operating parameters were investigated in this study. The rate constants of adsorption were determined at different concentrations and temperatures. The applicability of the first-order reversible equation and an empirical kinetic model were tested to understand the kinetics of nickel sulphate removal at different concentrations. Pore diffusion was found as the rate-controlling step. The Langmuir and Freundlich isotherms were applied to find out the adsorption parameters. The activation energy of adsorption was -11.54 kJ mol-1. The value of the enthalpy change was ?H=-10.35 kcal mol-1.

Why do people non-demand reveal in hypothetical double referenda for public goods?

Hypothetical contingent valuation surveys used to elicit values for environmental and other public goods often employ variants of the referendum mechanism due to the cognitive simplicity and familiarity of respondents with this voting format. One variant, the double referendum mechanism, requires respondents to state twice how they would vote for a given policy proposal given their cost of the good. Data from these surveys often exhibit anomalies inconsistent with standard economic models of consumer preferences. There are a number of published explanations for these anomalies, mostly focusing on problems with the second vote. This article investigates which aspects of the hypothetical task affect the degree of nondemand revelation and takes an individual-based approach to identifying people most likely to non-demand reveal. A clear profile emerges from our model of a person who faces a negative surplus i.e. a net loss in the second vote and invokes non self-interested, non financial motivations during the decision process.

”Bricks vs. Clicks”: The impact of manufacturer encroachment with a dealer leasing and selling of durable goods

In durable goods markets, many brand name manufacturers, including IBM, HP, Epson, and Lenovo, have adopted dual-channel supply chains to market their products. There is scant literature, however, addressing the product durability and its impact on players’ optimal strategies in a dual-channel supply chain. To fill this void, we consider a two-period dual-channel model in which a manufacturer sells a durable product directly through both a manufacturer-owned e-channel and an independent dealer who adopts a mix of selling and leasing to consumers. Our results show that the manufacturer begins encroaching into the market in Period 1, but the dealer starts withdrawing from the retail channel in Period 2. Moreover, as the direct selling cost decreases, the equilibrium quantities and wholesale prices become quite angular and often nonmonotonic. Among other results, we find that both the dealer and the supply chain may benefit from the manufacturer’s encroachment. Our results also indicate that both the market structure and the nature of competition have an important impact on the player’s (dealer’s) optimal choice of leasing and selling.

Leisure goods, education attainment and fertility choice

This paper proposes a novel mechanism for the fertility decline that occurred across the world since the late nineteenth century. It suggests that the rise in the cost of children relative to leisure goods in the process of development contributed to the decline in fertility. The paper develops a unified growth model in which children are substitutes for leisure goods in the parental utility function. The theory suggests that the rise in income, the decline in the relative price of leisure goods and the increase in educational attainment in the process of development speed up the demographic transition from high to low fertility and contributed to the transition from stagnation to growth.

Clarification of rubber mill wastewater by a plant based biopolymer- comparison with common inorganic coagulants

Background: In this study, the efficiency of Guar gum as a biopolymer has been compared with two other widely used inorganic coagulants, ferric chloride (FeCl3) and aluminum chloride (AlCl3), for the treatment of effluent collected from the rubber-washing tanks of a rubber concentrate factory. Settling velocity distribution curves were plotted to demonstrate the flocculating effect of FeCl3, AlCl3 and Guar gum. FeCl3 and AlCl3 displayed better turbidity removal than Guar gum at all settling velocities.

Result: FeCl3, AlCl3 and Guar gum removed 92.8%, 88.2% and 88.1% turbidity, respectively, of raw wastewater at a settling velocity of 0.1 cm min-1, respectively. Scanning electron microscopic (SEM) study conducted on the flocs revealed that Guar gum and FeCl3produced strong intercoiled honeycomb patterned floc structure capable of entrapping suspended particulate matter. Statistical experimental design Response Surface Methodology (RSM) was used to design all experiments, where the type and dosage of flocculant, pH and mixing speed were taken as control factors and, an optimum operational setting was proposed.

Conclusion: Due to biodegradability issues, the use of Guar gum as a flocculating agent for wastewater treatment in industry is highly recommended.

The ageing behaviour of hydrogenated nitrile butadiene rubber/nanoclay nanocomposites in various mediums

Hydrogenated nitrile butadiene rubber (HNBR) nanocomposites were prepared using commercially available organoclays (Cloisite 15A). The main focus of the current investigation is to study the influence of the organoclay reinforced in HNBR after subjecting it to long-term oxidative ageing and immersion studies. All the different nanoclay nanocomposites were air aged for a period of 168 h and at 150°C. The changes in the mechanical properties such as tensile strength and elongation at break have been compared with respect to the control sample. For immersion tests, three different liquid mediums were considered for this current investigation. All the samples were immersed in different mediums for a period of 168 h at 150°C. The changes in the swelling index and the mechanical properties have been reported with respect to the control sample. After reinforcing nanoclays into HNBR there was good resistance to swelling in all the three different liquid mediums in comparison to control sample. Tensile testing was performed on the immersed nanocomposites to evaluate the mechanical behaviour after immersion studies. A probable mechanism behind the improved performance has been suggested. © The Author(s) 2012.

Influence of nanoclays on mechanical and barrier properties of hydrogenated acrylonitrile butadiene rubber nanocomposites

In this research, two different methods have been investigated for optimising the preparation of hydrogenated acrylonitrile butadiene rubber/clay nanocomposites. Commercially available organoclay (Cloisite 20A) has been considered for the preparation of rubber nanocomposites. A detailed analysis has been made to investigate the morphological structure and mechanical behaviour at room temperature and at elevated temperature. Also the influence of organoclays on permeability has been studied. Structural analysis indicates very good dispersion for a low loading of 5 parts per hundred (phr) amount of nanoclays. Significant improvements in mechanical properties have been observed with the addition of organoclays at both room and elevated temperatures. Even with the low level of addition of nanoclays, there was a remarkable reduction in permeability. © Institute of Materials, Minerals and Mining 2011.

Neoliberalism, the University, Public Goods, and Agricultural Innovation

After World War II, most industrialising nations adopted some form of welfare-state approach to balance the economic activities of self-interested agents and social welfare. In the realm of scientific research and innovation, this often meant that governments took primary responsibility for funding public research organisations, including research universities and government laboratories. Over the past four decades, however, the significance of private funding for agricultural research has increased, and academic scientists now often work in public-private partnerships. We argue that this trend needs to be carefully monitored because public goods are likely to be overlooked and undervalued in such arrangements. In the interest of developing indicators to monitor the trend, we document public and private funding for agricultural research and agricultural innovation in four countries: the USA, the UK, Ireland and Germany. Our results show that although neoliberalism is evident in each country, it is not homogeneous in its application and impacts, suggesting that national and institutional contexts matter. This article is directed at stimulating debates on the relationships between university research, agricultural innovation and public goods.