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A numerical investigation is carried out to study the mixed convection of Al2O3-Cu/water hybrid-nanofluid in a vertical tube fitted with elliptical-cut twisted tape inserts (TECT). Thermodynamic irreversibilities are evaluated by calculating the Bejan number, as well as the system's local and total entropy generation. Heat transfer, friction factor, thermal performance factor, and entropy generation analyses are conducted for a range of volumetric concentrations of nanoparticles and flow Reynolds numbers between 7000 and 15,000. The realizable k- ε model is employed to simulate the turbulent and heat transferring flow computationally. The results clearly demonstrate the influence of mixed convection on heat transfer and entropy generation. In particular, mixed convection simulations predict greater Nusselt number, friction factor, and thermal performance factor than the corresponding forced convection simulations. Further, it is shown that the Nusselt number and the thermal performance factor for mixed convection are 4.6% and 5.5% higher than those for forced convection, respectively. The results also reveal that at Reynolds numbers of 7000, 9000, and 11,000, the thermal entropy production dominates the total irreversibility of the system. Likewise, frictional entropy production is the dominant mode of total irreversibility in the system at high Reynolds numbers of 13,000 and 15,000. [ABSTRACT FROM AUTHOR]

This paper presents a theoretical investigation of the second law performance of double diffusive forced convection in microreactors with the inclusion of nanofluid and radiation effects. The investigated microreactors consist of a single microchannel, fully filled by a porous medium. The transport of heat and mass are analysed by including the thick walls and a first order, catalytic chemical reaction on the internal surfaces of the microchannel. Two sets of thermal boundary conditions are considered on the external surfaces of the microchannel; (1) constant temperature and (2) constant heat flux boundary condition on the lower wall and convective boundary condition on the upper wall. The local thermal non-equilibrium approach is taken to thermally analyse the porous section of the system. The mass dispersion equation is coupled with the transport of heat in the nanofluid flow through consideration of Soret effect. The problem is analytically solved and illustrations of the temperature fields, Nusselt number, total entropy generation rate and performance evaluation criterion (PEC) are provided. It is shown that the radiation effect tends to modify the thermal behaviour within the porous section of the system. The radiation parameter also reduces the overall temperature of the system. It is further demonstrated that, expectedly, the nanoparticles reduce the temperature of the system and increase the Nusselt number. The total entropy generation rate and consequently PEC shows a strong relation with radiation parameter and volumetric concentration of nanoparticles. [ABSTRACT FROM AUTHOR]

The article focuses on the effect of corporate governance on business success. New Zealand Business Roundtable executive director Roger Kerr says people tend to blame governance when businesses fail rather than accepting failure as part of the swings and roundabouts of the corporate cycle. New Zealand Exchange Ltd. chief executive Mark Weldon said corporate governance was widely recognised as an important tool for improving accountability, transparency and certainty.

The article explains the decline of state-sector governance in New Zealand. With their own governing legislation, the State-Owned Enterprises Act 1986, they set about making history and providing a role model for public-sector restructuring worldwide. Key findings of a survey conducted by senior lecturer Richard Norman regarding the governance of the New Zealand public sector are mentioned. INSET: What the Government can do.

The article considers the decision of State-Owned Enterprises Minister Trevor Mallard to launch state-owned enterprises on a new path to bring economic transformation in New Zealand. The Labour Party is adopting the economic transformation mantra as of July 2006. Now the Government extends its reach into the private sector by regulation and through the power of state-owned enterprises. INSET: MALLARD SET TO FATHER BABY SOES.

This article explores the issue of infrastructure problem in New Zealand. The news clippings say it all: millions of dollars gobbled up in petrol, time wasted, and businesses under threat because of congested roads, likely shortages in electricity and the slow uptake of broadband. It is a national problem but south of the Bombay Hills the public dismisses it largely as "Auckland's problem". Roads, sometimes crowded before dawn and nearly always after dusk, top the list of infrastructural blackspots. Add to that fears of electricity shortages - most businesses have not forgotten the blackouts of 1998 caused by a failure in the isthmus transmission system-and Auckland has, according to the critics, joined the Third World. INSET: PIPE-MAKER'S NIGHTMARE.

The article discusses outlook for managerial posts in New Zealand for 2006. Despite redundancies and downsizing of organizations, demand for top managers remains strong. There is a need for more emphasis on internal learning, coaching and mentoring. Murray Jack, CEO of Deloitte, believes that reaction of companies to business trends in 2006 depends on the parts of the economy they are exposed to. INSET: A CONTRARIAN'S CASE STUDY.

Discusses the success of the model and process of corporate governance of Fonterra Co-Operative Group, a dairy company based in New Zealand. Impact of the separation of governance and representation through the creation of a shareholders' council on the performance of the company; Role of the shareholders' council in business management; Definition of corporate governance according to the policies of Fonterra; Importance of corporate governance to the direction of companies.

Profiles Deloitte New Zealand chairman and partner John Hagen. Reason for retiring from his job in 2005; Personal interests and hobbies; Management style.

A letter to the editor in response to Trevor Richards' review of "Spies and Revolutionaries," in the Autumn issue is presented.