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Hydrogen is a promising replacement for fossil fuels since it can be produced using renewable resources. However, hydrogen storage and transportation are the two significant barriers to the implementation of hydrogen-fuelled energy systems. Nevertheless, this issue can be solved by producing hydrogen on-board by methanol steam reforming. Methanol has a higher hydrogen/carbon ratio when compared to other hydrocarbons and it can be obtained from renewable sources such as biomass and stored and carried on-board. Further, the addition of hydrogen/hydrogen-rich reformates as secondary fuel can significantly improve the efficiency of internal-combustion engines and reduce emissions. In methanol-reformation, the type of catalyst and reactor design affect hydrogen yield and selectivity. This review focuses on the recent advancements in developing catalysts and reactors for methanol steam reforming and integration of methanol-reformers with internal-combustion engines for on-board production of hydrogen and its utilization as a secondary fuel. Different catalysts and their synthesis methodologies, promotors, and additives adopted for methanol reformation are compared. The applicability of novel catalysts such as spinels, perovskites and metal-organic frameworks is scrutinised. Moreover, the active sites involved, and mechanistic pathways are investigated. Additionally, the merits and demerits of conventional fixed-bed reactors, and the structural features and the benefits of micro-reactors studied are critically analysed. The integration of a methanol-reformer with an internal-combustion engine exhaust through a heat exchange system, a technique known as thermo-chemical recuperation and the influence of hydrogen-rich reformates on engine performance, thermal efficiency and emissions are deliberated. [Display omitted] • Recent developments in methanol steam reforming catalysts are discussed. • Structural features of fixed-bed and micro-reactors are critically analysed. • Suitability of catalysts and reactors for on-board hydrogen production is reviewed. • Advantages of adding reformates to the engine feed are highlighted. • Integration of methanol-reformers with internal-combustion engines is analysed. [ABSTRACT FROM AUTHOR]

Metadiscourse is an interesting linguistic and cultural construct of interpersonal communication which affects the process of communication in order to achieve communicative goals of persuasion, negotiation and information-transmission. This culturally grounded linguistic phenomenon of interaction has been widely studied in different discourses of various disciplinary cultures such as media discourse, academic discourse, and particularly research discourse. The text types of research discourse including theses, dissertations, and research articles produced by the authors belonging to various disciplines of hard and soft fields have gained special attention of the researchers. The findings of these studies not just helped understanding culture oriented disciplinary variation of interaction but the results have also been proven reliable guide for novice researchers engaged in producing research discourse especially in their second language which is usually English. Unfortunately, this metadiscursive practice which is responsible for making interaction more communicative has been neglected in academic context of Pakistan. Therefore, the current study attempts at exploring employment of metadiscourse with the perspectives of its occurrence and prototypicality (i.e. conventional usage) in research discourse produced by the authors of History research articles published in Pakistani research journals. Emerging techniques of corpus linguistics were used in analyzing employment of metadiscourse quantitatively and qualitatively. The study found conventionally localized use of metadiscourse grounded in restricted disciplinary cultural schema which demonstrates metadiscursive strategies causing the interactional practice to some extent less communicative. Considering these results, we suggest an eclectic model of teaching academic writing to postgraduate students in order to make their research discourse more effective and communicative. [ABSTRACT FROM AUTHOR]

Abstract: Managing salinity in irrigated agriculture is crucial for minimising its negative environmental impacts and for ensuring the long-term sustainability of irrigated agriculture. It demands establishing rapid monitoring systems that help develop sustainable management plans. Remote sensing offers several advantages over the conventional proximal methods to map and predict areas at salinity risk. This paper presents an integrated approach to characterize soil salinity using remotely-sensed data in the District Faisalabad, Punjab, Pakistan. The IRS-1B LISS-II digital data was acquired and analysed in combination with field data and topographical maps. Remotely-sensed data based salinity indices or band combinations were developed to monitor the occurrence pattern of salt-affected soils. Using supervised maximum likelihood classification, the images were classified into eight land use classes with an overall accuracy of around 90%. The classified images showed that 22.2% of the total area was under salt-affected soils in 1992. The occurrence pattern of salt-affected soils varied with positive and negative trends during 1992–1995 to a minimum of 10.6%. The delineation analysis into levels of saline soils revealed three types based on USDA classification (USDA, 1954). The slightly saline, moderately saline and strongly saline soils during 1992 were in the order of 15%, 3%, and 1% respectively. The interactive behaviour of salinity and sodicity and their combinations showed that saline-sodic soils occurred predominantly ranging from 6.9% to 17.3% of the salt-affected soils. The shallow watertable was found to be of hazardous quality in 28% of the study area. The relationship between salt-affected soils, waterlogged soils and groundwater quality revealed that 60–70% of the salt-affected soils occurred in shallow watertable areas during 1992–1995. The reuse of poor quality groundwater for irrigation and the failure of tile drainage system in the area are likely to further increase the risk of salinisation in the Indus Basin of Pakistan. [Copyright &y& Elsevier]

Much of inland Australia has been in perpetual drought since 1997 except during 2010 when above average rainfall occurred. It has been the worst drought since 1788 when European settlement began. Water scarcity poses a serious threat to the sustainability of the irrigated agriculture in major irrigation systems across the Murray-Darling Basin (MDB). There is a need for water-saving measures and a structured approach to assess water loss in earthen supply channels. This paper presents such an approach to assess and reduce seepage losses for improving irrigation efficiencies. Main elements of this approach are the following: field measurements, hydrologic modelling, potential options for seepage reduction, economic analysis and financing water-saving investments. Using data from two irrigation systems in the southern MDB, a case is made for reducing seepage water losses in irrigation supply channels in a cost-effective manner using low-cost technologies. Increasing the level of security for investments in water-saving programs provides incentives to key stakeholders to achieve water-saving targets. Considering the value of water recovered from reducing seepage loss at irrigation system level, this study demonstrates how reducing just one component (seepage) from the total water losses in irrigation systems can help improve water supplies as well as the environmental flows. Potential options for financing infrastructure improvement for saving irrigation water are proposed and discussed. [ABSTRACT FROM AUTHOR]

Abstract: In this study, spatial analysis techniques were used to generate climatic zoning maps of the East Murrumbidgee Irrigation Area (MIA), Australia. Long term climate data were used to analyze and assess regional climatic variation by cluster analysis in a GIS environment. Based on thermal and moisture factors, four variables were chosen to develop climate zones. These variables include annual average rainfalls, annual average ETc, annual average Growing Day Degree (GDD) and daily average temperature generated from daily climate data of 36years (1971–2006) on 12 local weather stations as the fundamental elements of regional climate characteristics. GIS-based spatial analysis models are used to map climate sub-regions from sets of climatic parameters derived from regional climate data sources. Two climate zoning schemes are presented by integration of spatial interpolation, spatial cluster analysis and climate indices methods. One scheme comes with the two climate zones of the West and the East based on spatial cluster analysis according to selected climatic variables, and the other comes with the three comprehensive hydro-thermal zones and the six hydro-thermal balance zones. [Copyright &y& Elsevier]

Wetlands are among the most valuable ecosystems in the world and are crucial in supporting biodiversity. They also provide space for storing surface waters, where intense biological processing occurs that helps improve water quality. Human activities, particularly irrigated agriculture and urban developments instigating water diversions from rivers, have altered the hydrology of most wetlands. The Lower Murrumbidgee wetland, located in the Murrumbidgee River Catchment, is an example and is one of the significant wetlands across the Murray Darling Basin of Australia. Historic estimates show the volumes of water ranged from none in dry years to about 300 to 400 GL (1 GL = 109 L) in an average and wet year respectively. The flows reaching the Lower Murrumbidgee wetland have been drastically reduced by at least 60% because of the upstream diversions introduced during the last century. These reductions have adversely affected the health of natural vegetation and agricultural crops in the Lower Murrumbidgee floodplain. This article presents the results of the quantification of total water consumption of various land uses in the Lower Murrumbidgee flood plain using the remote sensing--based Surface Energy Balance Algorithm for Land (SEBAL) modeling approach The spatial analysis of actual evapotranspiration (ETa shows that ETa rates are the highest (13-26%) for the red gum (Eucalyptus camaldulensis) forests both in summer and winter days. However, in terms of total ETa volume lignum (Muehlenbeckia florulenta) constitutes the most significant part, which is around 14-30% of the total ETa volume for the area. Actual evapotranspiration from winter cereal cropping areas following the summer ponding is the third highest consumer of water after the river red gum and lignum. Actual evapotranspiration from the fallow land is also significant, representing 5-28% total ETa from the region. In view of the extent of the unaccounted flows in the overall water balance of the system, there is a need to upgrade measuring and reporting infrastructure by strengthening the institutional and management arrangements to better gauge the efficiency of environmental and consumptive water use. The state-of-the-art technology of remote sensing--based SEBAL modeling proved to have potential for measuring actual water use with reliable accuracy and can be used for assessing the environmental and productive use of water from wetlands in other regions of Australia. [ABSTRACT FROM AUTHOR]

Buildings release an abundance of waste heat that is left unused. Thermogalvanic cells (TGCs) can take advantage of waste heat to generate electricity with a low temperature gradient. Application of Triply Periodic Minimal Surface (TPMS) structures allow TGCs to potentially be used as building components for construction. TPMS in TGCs increase thermal resistance and the magnitude of increase varies by the type of TPMS used. Natural convection effects are one of the driving forces in TGCs, and those effects can be controlled with the use of TPMS structures while at the same time allowing the electrochemical process to occur. In this study, we ran multiple experiments for the TGCs with the Split P, Schwarz P, Gyroid, and IWP TPMS structures. Split P consistently gave relatively higher thermal resistances (0. 012 m − 2 K W ) because of its higher surface area/volume ratio which effectively increased the temperature difference across the cell. The TGC containing the IWP structure had the least thermal resistance because of a low surface area as well as having large void spaces which increased heat transfer across the TGC. Furthermore, we simulated the thermal transport of the TGC containing the Schwarz P structure. By using the Boussinesq approximation, we were able to capture natural convection effects in our CFD simulations. The deviation of the Δ T from the experiment and simulation was due to the placement of the thermocouples at the top side of the electrode. This means that the measured electrode temperatures were overestimated since the warmer fluid was always present at the top while the simulated electrode temperature was calculated by taking the mean temperature of the electrode. The simulated thermal resistance matched the experimental values when the temperature was taken from the top sides of the electrodes, and was found to be 0.007 ± 0. 001 m − 2 K W . [ABSTRACT FROM AUTHOR]

Let G = Z p ⊕ Z p 2 , where p is a prime number. Suppose that d is a divisor of the order of G. In this paper, we find the number of automorphisms of G fixing d elements of G and denote it by θ (G , d) . As a consequence, we prove a conjecture of Checco-Darling-Longfield-Wisdom. We also find the exact number of fixed-point-free automorphisms of the group Z p a ⊕ Z p b , where a and b are positive integers with a < b . Finally, we compute θ (D 2 q , d) , where D 2 q is the dihedral group of order 2 q , q is an odd prime, and d ∈ { 1 , q , 2 q } . [ABSTRACT FROM AUTHOR]