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An energetic upgrade factor has been defined as the ratio of the lower heating value (LHV) of the syngas (H 2 plus CO) produced plus unreacted feedstock to that of the feedstock processed. It is used to evaluate the thermal performance of the steam reforming of methane,mixed reforming of methane with steam and carbon dioxide, and carbon dioxide reforming of methane based on the calculated equilibrium product compositions. A non-stoichiometric equilibrium model was developed using FactSage 6.3 software to conduct the thermodynamic calculations for production of syngas. The results show that increasing temperature or decreasing pressure can enhance the energetic upgrade factor of all three reforming processes. The ratio of the feedstock components has an effect on the energetic upgrade factor for the three reforming processes. There is an optimum ratio exisitng that provides the highest energetic upgrade factor for each of the three reforming processes. Replacement of H 2 O by CO 2 can enhance the energetic upgrade factor, particularly at high temperatures with no carbon formation. The analysis also identifies operating regimes where carbon formation is thermodynamically possible as well as discusses the undesirable effect that this carbon formation has on the energetic upgrade factor.

The effect of H 2 S on the performance of La 0.7 Ce 0.2 FeO 3 perovskite catalyst was investigated for the production of hydrogen from simulated coal-derived syngas via the water–gas shift reaction at 600 °C and 1 atm. The results show that the catalyst activity decreases with increasing concentrations of H 2 S up to 1100 ppm, but the negative effect of H 2 S on its activity is reversible. However, even at the high H 2 S concentrations catalyst activity is still greater than that measured with sour shift catalyst. Overall, the results indicate that La 0.7 Ce 0.2 FeO 3 perovskite catalyst has a high degree of H 2 S tolerance, particularly in the low H 2 S concentration regime.

Thermodynamic analysis of the reforming of methane with carbon dioxide alone (“dry reforming”) and with carbon dioxide and steam together (“mixed reforming”) is performed as part of a project which investigates the suitability of these endothermic reactions for the storage of solar thermal energy. The Gibbs free energy minimization method was employed to identify thermodynamically optimal operating conditions for dry reforming as well as mixed reforming with a desired H 2 /CO molar ratio of 2. The non-stoichiometric equilibrium model was developed using FactSage software to conduct the thermodynamic calculations for carbon formation, H 2 /CO ratio, CH 4 conversion and H 2 yield as a function of reaction temperature, pressure and reactant molar ratios. Thermodynamic calculations demonstrate that in the mixed reforming process, optimal operating conditions in a carbon-free zone are under H 2 O/CH 4 /CO 2 = 1.0/1.0/0.5, p = 1 to 10 bar and T = 800 to 850 °C for the production of syngas with a H 2 /CO molar ratio of 2. Under the optimal conditions, the maximum H 2 yield of 88.0% is achieved at 1 bar and 850 °C with a maximum CH 4 conversion of 99.3%. In the dry reforming process, a carbon formation regime is always present at a CO 2 /CH 4 molar ratio of 1 for T = 700-1000 °C and p = 1-30 bar, whereas a carbon-free regime can be obtained at a CO 2 /CH 4 molar ratio greater than 1.5 and T ≥800°C.

The performance of a commercially-available sour shift catalyst (SSC1) under selected syngas compositions was investigated and kinetic parameters were obtained. The watergas shift experiments were carried out in a differential reactor using simulated syngases containing a constant level of H2S concentration of 1000 ppm on a wet basis at 450 °C and atmospheric pressure. The following kinetic relationship has subsequently been developed to describe the performance of catalyst SSC1 at a reaction temperature of 450 °C (723 K) and atmospheric pressure using a power–law model: R = 0.008 ± 0.0004 exp ( − 60.3 ± 1.3 R ′ T ) P CO 0.75 ± 0.12 P H 2 O 0.31 ± 0.08 P CO 2 − 0.07 ± 0.02 P H 2 − 0.09 ± 0.02 ( 1 − 1 K ⋅ P CO 2 P H 2 P CO P H 2 O ) The effect of varying H2S concentration on the performance of the sour shift catalyst was investigated using simulated dry-feed coal-derived syngas. It was found that its reactivity is significantly improved by the presence of sulfur. The reaction order with respect to H2S concentration in the feed gas was calculated to be 0.52 ± 0.02 for a wide range of H2S concentrations (330–2670 ppm). The activity of the sour shift catalyst is very poor compared to those of commercial high-temperature water–gas shift catalysts when the concentration of H2S in the syngas is lower than 500 ppm. It was found that the sour shift catalyst has an advantage over the high-temperature catalysts tested in this study only if the H2S concentration in the coal-derived syngas is consistently maintained at levels greater than 1000 ppm on a wet basis.

The kinetics of the water-gas shift (WGS) reaction over a novel La0.7Ce0.2FeO3 perovskite-like catalyst is investigated using simulated coal-derived syngas at temperatures of 550 °C and 600 °C which are higher than the maximum operating temperature limit for conventional high temperature WGS catalysts. The influences of CO, CO2, H2O and H2 concentration on WGS reaction rate are determined using selected gas compositions that might be encountered in a coal-based gasification system. An empirical power-law rate model used in this study is found to correlate well with experimental data with good accuracy. Kinetics parameters over La0.7Ce0.2FeO3 obtained in this study are mostly in agreement with those previously measured using Fe–Cr based commercial catalysts in a range of relatively lower temperatures (300–500 °C).

La (0.9− x ) Ce x FeO 3 perovskite-like catalysts were investigated for the production of hydrogen from simulated coal-derived syngas via the water–gas shift reaction in the temperature range 450–600 °C and at 1 atm. These catalysts exhibited higher activity at high temperatures ( T ≥ 550 °C), compared to that of a commercial high temperature iron–chromium catalyst at 450 °C. Addition of a low Ce content ( x = 0.2), has little influence on the formation of the LaFeO 3 perovskite structure, but enhances catalytic activity especially at high temperatures with 19.17% CO conversion at 550 °C and 40.37% CO conversion at 600 °C. The LaFeO 3 perovskite structure and CeO 2 redox properties play an important role in enhancing the water-gas shift activity. Addition of a high Ce content ( x = 0.6) inhibits the formation of the LaFeO 3 perovskite structure and decreases catalyst activity.

CeO2–La2O3-based Cu catalysts were investigated for their ability to produce hydrogen from simulated coal-derived syngas via the water–gas shift reaction in the temperature range of 450–600 °C. CeO2–La2O3-based Cu catalysts exhibited high activity and stability at high temperatures (T ≥ 550 °C) with dry-gas hourly space velocity = 239,000 ml/h gcat. and at atmospheric pressure. Furthermore, the activity of CeO2–La2O3-based Cu catalysts was found to be proportional to the magnitude of Cu% dispersion and Cu metal surface area with the highest Cu% dispersion and Cu surface area appearing at the La/Cu atomic ratio of 2.7, achieving the highest activity with 7.8% CO conversion at 550 °C and 21.5% CO conversion at 600 °C, much higher than commercial iron–chromium high temperature shift catalyst with 5.9% conversion at 450 °C. Substitution of Ce by Al in CeO2–La2O3-based Cu catalysts decreased catalyst activity and stability in the temperature range 550–600 °C, indicating that CeO2 plays an important role in maintaining high activity and stability. Addition of Ni to CeO2–La2O3-based Cu catalysts improved their activity at 450 °C, but led to reduced activity at temperatures of 550 °C and above. The high activity and stability observed may originate from the synergistic effect of the interaction between Cu2+ species and catalyst support as well as the redox behaviour of the catalyst support.

Novel Cu-based catalysts supported on both Ce–La–Al and Ce–Zr–Al supports were investigated for the water–gas shift reaction in the temperature range 450 to 600 °C. Ce–La–Al containing Cu catalysts exhibited high activity and stability for the high temperature water–gas shift reaction with catalyst 10%Cu / (36.8%CeO 2 + 30.2%LaO x + 33.0%AlO x ) (CE18), achieving the highest activity with 15.5% CO conversion at 600 °C and atmospheric pressure, higher than its counterpart Ce–Zr–Al containing Cu catalyst. This high activity and stability may originate from the synergistic effect of the interaction between Cu and catalyst support, the redox behaviour of catalyst support as well as the stabilizing effect of Al 2 O 3 .

Although the gasification of coal is an efficient means of producing syngas, the carbon content of coal is such that gasification produces significantly higher ratios of carbon oxides to hydrogen than those obtained by the steam reforming of natural gas. The CO:H2 ratio can be adjusted, and more hydrogen produced, by the subsequent application of the water–gas shift (WGS) reaction. This article presents a review of technologies associated with the catalytic WGS reaction in a fixed-bed reactor that might be incorporated into a coal gasification-based system for H2 production with CO2 capture. The main output from this review is the identification of key project areas requiring further research. The performance of existing, commercially available catalysts—designed for use in natural gas reforming processes—with coal-derived syngases is an important aspect of developing technologies for coal-based H2 production. This article presents an experimental assessment of the performance of selected commercially available WGS catalysts, two high-temperature catalysts (HT01 and HT02) and a sour shift catalyst (SS01), with such syngases. For the three commercial catalysts investigated in this study, CO reaction order is found to be in a range of 0.75–1. The effect of changes in H2O concentration over HT01 is insignificant, whereas H2O reaction orders determined using HT02 and SS01 are found to be significantly positive even at high H2O:C ratios. The CO conversion rate is significantly reduced by increasing CO2 concentration, whereas increasing H2 concentration also causes a slight reduction in CO conversion rate for the three commercial catalysts investigated. Copyright © 2010 Curtin University of Technology and John Wiley & Sons, Ltd.

The effect of operating pressure on the water–gas shift (WGS) reaction rate over an iron-based high-temperature catalyst, and a Co–Mo based sour-shift catalyst, was investigated using simulated coal-derived syngas at 450 °C. For both catalysts, it was found that the CO conversion rate depends linearly upon total operating pressure. The apparent reaction orders used in a power-law rate expression, where the reaction orders were derived from experimental results at atmospheric pressure, are valid at elevated pressures up to at least 11 bar.

Seismic reflection profiles and vibracores have revealed that an inner shelf, sand-ridge field has developed over the past few thousand years situated on an elevated, broad bedrock terrace. This terrace extends seaward of a major headland associated with the modern barrier-island coastline of west-central Florida. The overall geologic setting is a low-energy, sediment-starved, mixed siliciclastic/carbonate inner continental shelf supporting a thin sedimentary veneer. This veneer is arranged in a series of subparallel, shore-oblique, and to a minor extent, shore-parallel sand ridges. Seven major facies are present beneath the ridges, including a basal Neogene limestone gravel facies and a blue-green clay facies indicative of dominantly authigenic sedimentation. A major sequence boundary separates these older units from Holocene age, organic-rich mud facies (marsh), which grades upward into a muddy sand facies (lagoon or shallow open shelf/seagrass meadows). Cores reveal that the muddy shelf facies is either in sharp contact or grades upward into a shelly sand facies (ravinement or sudden termination of seagrass meadows). The shelly sand facies grades upward to a mixed siliciclastic/carbonate facies, which forms the sand ridges themselves. This mixed siliciclastic/carbonate facies differs from the sediment on the beach and shoreface, suggesting insignificant sediment exchange between the offshore ridges and the modern coastline. Additionally, the lack of early Holocene, pre-ridge facies in the troughs between the ridges suggests that the ridges themselves do not migrate laterally extensively. Radiocarbon dating has indicated that these sand ridges can form relatively quickly (∼1.3 ka) on relatively low-energy inner shelves once open-marine conditions are available, and that frequent, high-energy, storm-dominated conditions are not necessarily required. We suggest that the two inner shelf depositional models presented (open-shelf vs. migrating barrier-island) may have co-existed spatially and/or temporally to explain the distribution of facies and vertical facies contacts.

High-resolution side-scan mosaics, sediment analyses, and physical process data have revealed that the mixed carbonate/siliciclastic, inner shelf of west-central Florida supports a highly complex field of active sand ridges mantled by a hierarchy of bedforms. The sand ridges, mostly oriented obliquely to the shoreline trend, extend from 2 km to over 25 km offshore. They show many similarities to their well-known counterparts situated along the US Atlantic margin in that both increase in relief with increasing water depth, both are oriented obliquely to the coast, and both respond to modern shelf dynamics. There are significant differences in that the sand ridges on the west-central Florida shelf are smaller in all dimensions, have a relatively high carbonate content, and are separated by exposed rock surfaces. They are also shoreface-detached and are sediment-starved, thus stunting their development. Morphological details are highly distinctive and apparent in side-scan imagery due to the high acoustic contrast. The seafloor is active and not a relict system as indicated by: (1) relatively young AMS 14C dates (

Two experiments were conducted with pansy (Viola ×wittrockiana Gams `Bingo Yello') to determine the relationship between foliar nitrogen (% of dry weight) (FN) and either sap nitrate concentration (SN) in petioles or SPAD readings of foliage. FN was highly correlated to SN throughout both experiments (r = 0.80 to 0.91). FN was poorly correlated to SPAD readings early in both experiments (r = 0.54 to 0.65), but more highly correlated later when visual symptoms of N deficiency were apparent (r = 0.84 to 0.90). SN determined with the Cardy sap nitrate meter was a reliable predictor of FN in pansy, while SPAD readings were only reliable after symptoms of N deficiency were visually evident. FN can be predicted with SN using the following equation: log(SN) = 0.47*FN + 1.6 [r2 = 0.80, n = 132]. Growers and landscape professionals can use SN readings to predict FN levels in pansy, and thus rapidly and accurately diagnose the N status of their crop.

Two experiments were conducted to evaluate fertilizer formulations, methods of application, and frequency of application on growth of winter-grown landscape bedding plants and N leaching. In Expt. 1, ‘Majestic Giants White’ pansy (Viola xwittrockiana Gams.) and ‘Telstar Purple’ dianthus (Dianthus chinensis L.) were planted in raised beds. Four inorganic fertilizer formulations were applied at 4.9 g/m2 N (1 lb N/1000 ft2) either incorporated pre-plant or topdressed post-plant. Additional treatments included an industry practice (IP) of incorporating a granular water soluble (GWS) fertilizer pre-plant and topdressing a controlled release fertilizer (CRF) post-plant, and a pre-plant incorporation of an organically-based fertilizer (OBF) composed of recycled newspaper amended with chicken manure. In Expt. 2, similar treatments were applied to the following species: ‘Bingo Blue with Blotch’ pansy, ‘Telstar Crimson Picotee’ dianthus, and ‘Tall Red’ snapdragon (Antirrhinum majus L.). Across both studies, CRFs generally improved foliar color and plant size compared to GWS fertilizers, while reducing total-N in soil-water in some instances. The IP treatment provided superior foliar color and larger plants compared to other inorganically fertilized plants, while causing no more or less total-N in soil-water leaching below plant roots. Response to the OBF differed among the two experiments. The OBF resulted in adequate foliar color and plant size and reduced total-N recovered from soil-water in Expt. 1. However, it generally provided superior foliar color and size compared to all other treatments in Expt. 2, but also caused elevated levels of total-N in soil-water.

Two experiments were conducted to evaluate fertilizer formulation, method of application, and frequency of application on growth of landscape bedding plants and nitrogen (N) leaching. In the first experiment, ‘Peppermint Cooler’ vinca (Catharanthus roseus (L.) G. Don ‘Peppermint Cooler’), ‘Bonanza Yellow’ marigold (Tagetes patula L. ‘Bonanza Yellow’), and ‘Hawaii Blue’ ageratum (Ageratum houstonianum Mill. ‘Hawaii Blue’) were planted in raised beds. Four inorganic fertilizer formulations used included 13N–5.6P–10.9K (13–13–13) and 15N–0P–12.6K (15–0–15) granular water soluble (GWS) fertilizers, Osmocote 14N–6.0P–11.6K (14–14–14) (3 to 4 month release) controlled-release fertilizer (CRF), and Osmocote 17N–3.0P–10.1K (17–7–12) (12 to 14 month release) CRF. Each fertilizer was applied at a rate of 4.9 g N/m2 (1 lb N/1000 ft2) either incorporated into the top 10.2 cm (4 in) pre-plant or topdressed postplant. Additional treatments included an industry practice of incorporating 13N–5.6P–10.9K (13–13–13) pre-plant and topdressing 17N–3.0P–10.1K (17–7–12) post-plant; and a pre-plant incorporation of an organically-based fertilizer composed of recycled newspaper amended with chicken manure (caged layer manure). In Expt. 2, a similar experimental setup was used with ‘Peppermint Cooler’ vinca, ‘Red Vista’ salvia (Salvia splendens F. Sellow ex Roem. & Schult. ‘Red Vista’), and ‘Strata’ salvia (Salvia farinacea Benth. ‘Strata’). Inorganic fertilizers were applied in either single or multiple applications. Inorganic fertilizers included 15N–0P–12.6K (15–0–15) GWS fertilizer, Osmocote 14N–6.0P–11.6K (14–14–14) CRF, and Osmocote 17N–3.0P–10.1K (17–7–12) CRF. Three organically-based fertilizers were applied pre-plant and were composed of recycled newspaper amended with either chicken, beef cattle, or dairy cow animal manures. Summarizing across both experiments, plants treated with GWS fertilizers appeared to benefit with improved foliar color from immediate release of nutrients, while those treated with CRFs required at least 4 weeks to achieve dark foliar color. Nutrient leaching below plant roots was greater for GWS compared to CRFs. The industry practice treatment provided some improved plant growth in both experiments; however, it also caused initially high levels of soil-water-N (SWN) in Expt. 1. The organically-based fertilizer resulted in larger, more attractive (higher foliar color ratings) plants than inorganic fertilizers, though it also resulted in the highest levels of SWN compared to all other treatments.

Solid state ionic technologies such as fuel cells, sensors, batteries, supercapacitors, hydrogen generation, storage devices and electrochromic windows are likely to play a major role in extending the life of existing fossil fuel resources by increasing the overall efficiency of energy generation and use. This will lead to a reduction in the emissions of greenhouse gases and pollutants. No single technology in isolation is likely to provide solutions for the energy and environmental needs of future generations. This paper briefly outlines the applications of solid state ionic technologies for sustainable energy generation and summarises key Australian initiatives in this field. It also emphasises the significance of a total systems approach and discusses integration of renewable and solid state ionic technologies for clean and sustainable energy generation.

Three experiments were conducted to develop a method for rapid determination of nitrogen (N) status in ‘Pacifica White’ vinca (Catharanthus roseus (L.) G. Don). In experiment 1, N was applied to potted vinca at 40, 80, 120, or 160 ppm N to produce plants ranging from N deficient to N sufficient. Data were collected 14, 28, and 42 days after treatment (DAT) and included flower number, growth index [(height + width + width) ÷ 3], and from recently matured foliage the following parameters: SPAD-502 readings, petiole sap nitrate (SN) concentration, and total-N (percent of dry weight) (FN). Experiment 2 was similar with the exception that N rates applied were 30, 60, 90, 120, 150, or 180 ppm N, and data were collected 14, 29, and 42 DAT. In experiment 3, N was applied at 0, 90, or 180 ppm N and data were collected 0, 4, 7, 10, and 14 DAT. In experiments 1 and 2, SPAD readings were poorly correlated to FN (correlation coefficients ranged from 0.35 to 0.88) and the relationship between FN and SPAD readings changed at different collection dates. Petiole sap nitrate concentration determined by a Cardy nitrate meter was highly correlated throughout the three experiments. Above 380 ppm SN, the relationship between FN and SN was determined to be: SN/1000 = 2.3 × FN-4.8 (r2 = 0.73, n = 104). In experiment 3, FN and SN readings were able to detect N deficiency in vinca by 4 DAT, despite lack of visual symptoms until 14 DAT. SPAD readings were not suitable for predicting FN and plant N status. SN was a reliable predictor of FN and thus could be used to rapidly determine plant N status.

Two experiments were conducted to evaluate recycled newspaper products as nutrient filters in the bottom of containers. In Expt. 1 with poinsettia, Euphorbia pulcherrima Willd. ex Klotzsch `Glory', three paper products were evaluated: ground paper, paper crumble, and paper pellets; each placed 2 or 3 cm deep in the bottom of containers, so that drainage holes were covered. Leachate samples were collected at the first irrigation after each liquid fertilization. Nitrate (NO3--N) and ammonium (NH4+-N) leachate concentrations were reduced up to 84% with recycled paper pellets, compared to the control (no paper). Recycled paper retained up to 732 mg of nitrogen (N) per container (paper pellets 3 cm deep). Shoot dry weight was reduced with paper pellets but was not affected by ground paper or paper crumble. In Expt. 2, `Freedom Red' poinsettias were grown with either single weekly applications of 500 mg·L-1 N from Peter's 20N-4.3P-16.6K, or 200 mg·L-1 N at each irrigation (2 or 3 times a week, as needed). Recycled paper treatments included paper crumble or paper pellets placed 2.5 cm deep in the bottom of containers, and a control without paper. Leachate NO3--N and NH4+-N concentrations were reduced up to 100% and 94%, respectively, 6 days after planting (DAP), and up to 57% and 50%, respectively, 25 DAP with paper crumble compared to nonpaper control. Paper pellets in the bottom of containers retained up to 776 mg N per container. Poinsettia shoot dry weight was lowest with paper pellets in the bottom of containers and continuous fertilization.

Two experiments were conducted to determine the effects of pelletized recycled paper mulch on container plant nutrition. In experiment 1 with Petunia floribunda Hort. ‘Midnight Madness’, 9 g (0.32 oz) of Osmocote 14N-6.2P-11.6K (14-14-14) was applied over or under 2.5 cm (1 in) of recycled paper pellet mulch, or to plants with no paper mulch (control). Leachate samples were collected after microirrigation. Both treatments with paper mulch reduced nitrate (NO3-N) and ammonium (NH4-N) levels in container leachate, compared to the control 21 days after planting (DAP). Shoot dry weight was reduced 53% and 70% for plants fertilized under and over the mulch, respectively, compared to the non-mulched control. At the end of the experiment 40–48% of the total N applied over or under mulch was retained by the recycled paper mulch. In experiment 2 with Petunia grandiflora Hort. ‘Ultra Blue’, mulch and three methods of fertilizer application (over mulch, under mulch, and incorporated in the substrate) were compared. Leachate NO3-N levels were reduced 72% or 68% with fertilizer placed over or under the mulch, respectively, when compared to a non-mulched topdressed treatment 21 DAP. When fertilizer was incorporated into the substrate, paper mulch reduced NO3-N leachate levels 87% compared to the non-mulched treatment. There were no significant differences in leachate NH4-N levels with fertilizer placed over or under the mulch when compared to a non-mulched control 21 DAP. When fertilizer was incorporated into the substrate, paper mulch reduced leachate NH4-N levels 82% compared to the non-mulched control. Shoot dry weight was 84 or 49% lower with fertilizer placed over or under the mulch, respectively, when compared to the topdressed, non-mulched treatment. However, plants grown with fertilizer applied under the mulch were 213% larger than plants with fertilizer applied over the mulch. When fertilizer was incorporated into the substrate, paper mulch reduced shoot dry weight 41% when compared to non-mulched plants. There were no differences between shoot dry weights of plants grown in non-mulched treatments with topdress fertilization or fertilizer incorporated.

Three experiments were conducted to evaluate the effectiveness of postemergence applied herbicides for hairy bittercress (Cardamine hirsuta L.) control in container-grown crops. Manage (halosulfuron), Image (imazaquin), Action (fluthiacet-methyl), Resource (flumiclorac pentyl), Trimec Southern (Mecoprop + 2,4-D + dicamba), and Gallery (isoxaben) were applied to emerged bittercress in ‘Variegata’ and ‘Big Blue’ liriope. ‘China Girl’ holly and ‘Midnight Flare’ azalea were also treated with Manage, Image, Trimec Southern, and Gallery to evaluate injury. Among all experiments, Gallery provided 90 to 100% bittercress control at the labeled rate of 1.12 kg ai/ha (1.0 lb ai/A) with no injury to liriope, holly, or azalea. Among non-flowering bittercress, Manage applied at 0.035 kg ai/ha (0.031 lb ai/A) provided 90 to 100% bittercress control, with slight to moderate injury to ‘Variegata’ liriope; Image applied at 0.070 kg ai/ha (0.062 lb ai/A) provided 73 to 99.5% bittercress control and caused severe injury to azalea; and Trimec Southern applied at 0.31 kg ai/ha (0.28 lb ai/A) provided 50 to 100% bittercress control and caused severe injury to liriope and azalea. However, using the same rates applied to flowering bittercress Manage, Image, and Trimec Southern provided only 55, 6, and 50% bittercress control, respectively. Action and Resource did not control bittercress.

Studies were conducted to evaluate recycled waste paper mulch as a means of controlling weeds in the production of container-grown crops. Two forms of recycled waste paper products were evaluated—pelletized and crumbled. Both were tested at two depths, 12.5 mm (0.5 in) and 25 mm (1 in). A fabric disk and a fabric disk treated with Spin Out were also evaluated. With both the recycled waste paper mulch treatments and the fabric disk treatments, spurge seed were sown either under or on top of the treatment. Recycled waste paper pellets applied to a depth of 25 mm (1 in) suppressed spurge germination, regardless of whether spurge seed were sown on top of the mulch or under the mulch. Recycled crumble provided poor spurge control at both depths, and there was increased spurge growth when spurge were sown on top of the mulch compared to when the seed were sown under the crumble mulch. Pellets at the 25 mm (1 in) depth, provided weed control equal to that of Rout (oxyfluorfen + oryzalin) herbicide. Results from the fabric disks showed limited spurge control was obtained with any treatment. Fabric disks allowed weed growth around the container circumference and in the area where the disk fits around the plant. Both cultivars of azaleas grown with recycled waste paper mulch were generally similar in size to non-treated control plants and Rout treated plants at 240 DAT (days after treatment). At 550 DAT plant growth was similar among all treatments except ‘Fashion’ azalea had smaller growth indices when grown with pellets compared to those grown with crumble. Container medium solution pH and electrical conductivity (soluble salts) were within the recommended range for acceptable plant growth. Research suggests that pellets applied at 25 mm (1 in) should provide effective non-chemical weed control resulting in less herbicide use and/or fewer hours of labor for weeding.

Two studies were conducted to evaluate recycled waste paper mulch for landscape plantings. In the first study, two recycled paper products (pellet and crumble) were applied at three depths. Application of recycled paper mulch at a depth of 25 or 50 mm (1 or 2 in) controlled prostrate spurge. However, in experiment 1, all four bedding plant species exhibited stunting of roots and shoots. In the second study, three annual species were mulched with the two recycled paper products applied at 25 mm (1 in) depth and treated with phosphorus (P) at 0, 3.75, or 7.5 mgL−1 (ppm) to bind suspected excess aluminum (Al). When no P was added, growth of ageratum was approximately half that of the non-mulched control plants. Addition of P at either rate resulted in similar growth compared to control plants. Shoot dry weight of geranium was greater than that of the control plants with 7.5 mg L−l of P. Shoot dry weight of marigold was unaffected by the addition of P. This research indicates that recycled paper mulch at a 25 mm (1 in) depth, provides weed control equal to or better than standard landscape treatments, and causes little or no growth suppression when amended with P.

Fall and spring collards (Brassica oleracea L. Acephala Group) were grown under one of three mulches (black plastic, ground newspaper, wood chips) and in a bare soil control. Mulch treatments were arranged in a factorial design with five rates of N fertilizer: 0, 67, 134, 201, or 268 kg N/ha. All fertilizer was preplant-incorporated into the bed before applying mulches and transplanting collards. Season did not affect collard yield, and there was no significant season × N rate interaction. Collard yields increased with increasing rates of N, with a maximum yield at 163 kg N/ha. Mulch type significantly affected collard yield, with fall collard yields highest under bare ground or wood chip mulches and spring yields highest under black plastic mulch. Collards produced under newspaper mulch produced the lowest yields in the fall and yields equal to bare soil and wood chips in the spring. Collards produced under newspaper mulch had less tissue N at harvest than those of any of the other treatments in both seasons. Collards produced on black plastic produced the lowest plant populations in both seasons. Wood chips and newspaper offer some appeal as low-input, small-scale mulches, but additional research to explore fertility management is necessary.

A brief background is given of the current and projected Australian energy scene (production, consumption, exports) and the associated greenhouse gas emission scene. Against this background a brief overview, indicative rather than comprehensive, follows of initiatives directed to mitigating greenhouse gas emissions which have been taken by governments (federal and state), industry sector-based organisations and the R&D community

CSIRO/Pacific Power research on using the reversible CO2/CH4 reforming reaction for solar energy storage and transport is described. Catalysts have been developed and used to conduct the forward and reverse reactions in fluidised-bed reactors under practical conditions without carbon formation. Thermochemical energy storage rates up to 30 MWth/tonne of catalyst were obtained. Closed and open loop thermochemical heat-pipes based on CO2/CH4 reforming have a range of applications in Australia. They have considerable potential in reducing the emissions of Greenhouse gases associated with the production of electricity and process heat. Results of a techno-economic evaluation of selected concepts are presented. Concepts for linking solar energy to the reformer have been identified and future work must focus on reactor scale-up and linking the reformer with solar energy.

Soil management practices that contribute to increased soil productivity and longterm sustainable agricultural production have been neglected over the last four decades. The need to increase soil productivity led to the evaluation of a system of disposing of large quantities of organic by-products and poultry litter on agricultural land. Our objectives were to evaluate the effects of applying noncomposted municipal solid waste (MSW), amended with either poultry litter (PL) or NH4NO3 to adjust C:N ratios in the soil surface in either the spring or fall. Changes in soil chemical properties, bacteria population shifts, changes in species richness and evenness of indigenous soil bacteria, and response by cotton (Gossypium hirsutum L.) were evaluated. Soil P, K, Ca, and Mg were increased in the surface 0–15 cm by a factor of three or four times by application of organic by-products. After two annual applications, soil Cu increased slightly, Zn doubled, Co and Cr decreased, while Pb increased by a factor of two...

Subsoiling and slit tillage can increase root growth through subsurface hardpans. In-row subsoiling fractures a section of the pan below the row. Slit tillage cuts a 3-mm-wide slit through the pan with a thin blade mounted on a shallow subsoil shank. Subsoiling is usually repeated annually. Slit tillage has been reported as an alternative to subsoiling that does not need to be repeated annually. This study was conducted to determine the longevity of the effects of tillage on a fine loamy Acrisol at Florence, South Carolina, USA. Corn (Zea mays) root growth, yield, and soil cone index were measured for 3 years in plots that had been slit tilled, in-row subsoiled, or no-tilled for 4 years immediately prior to the study. During the study, no plots were tilled. Three-year average corn yields were 5.08 Mg ha−1 for residual slit-tilled treatments, 5.34 Mg ha−1 for residual subsoiled treatments, and 5.07 Mg ha−1 for the no-tilled treatments. Three-year mean profile cone indices were 2.53 MPa for residual slittilled treatments, 2.51 MPa for residual subsoiled treatments and 2.61 MPa for no-tilled treatments. Only 10% of the slits could be found 3 years after tillage. The lack of persistence of the slits was a result of either slit infilling with sand from the Ap horizon or collapse of the slit walls. Roots grew to a depth of at least 0.95 m in all treatments. Root growth was not correlated with yield. In this soil, residual subsoiled treatments gave higher yields than no-tillage treatments, but residual slit tillage did not. If deep tillage is not performed annually, subsoiling would be better than not tilling, but slit tillage would not.

The reforming of CH 4 with CO 2 produces synthesis gas with a lower H 2 /CO ratio than that generated by the widely employed steam/CH 4 reforming reaction. The two reactions have similar thermodynamic characteristics except that in the case of CO 2 /CH 4 reforming there is a greater potential for carbon formation, primarily due to the lower H/C ratio of this system. Thermodynamic analysis of the CO 2 /CH 4 reforming reaction system shows that carbon formation is possible over a wide range of reaction conditions of possible commercial interest. Whilst technology has been developed to enable CO 2 /CH 4 and steam/CH 4 reforming to be carried out simultaneously, the former reaction has to date had no significant commercial application by itself. However, there is now renewed interest in C 1 -chemistry to produce chemicals and fuels requiring synthesis gas with a 1/1 H 2 /CO ratio. Conducted in the absence of steam/CH 4 reforming, CO 2 /CH 4 reforming has a number of major advantages over alternative chemical reactions for the thermochemical storage and transmission of renewable energy sources such as solar energy. Hence it is likely to become an increasingly important industrial reaction in the future. A review of the literature on the catalysis of CO 2 /CH 4 reforming shows that Group VIII metals, when distributed in reduced form on suitable supports, are effective catalysts for this reaction. Rh appears intrinsically to be the most suitable, and considering the relative material costs, Ni catalysts deserve closer attention. In the latter case the emphasis should be on developing catalysts which are capable of carbon-free operation under practical reaction conditions. Of the various supports studied to date, alumina and magnesia or combinations thereof are most promising. Analysis of the reaction mechanism indicates that the effective catalysts are those metal-support combinations which actively dissociate CH 4 into CH x residues including carbon, whilst at the same time also activating CO 2 to generate CO and an adsorbed O species on the catalyst surface. The O thus produced is consumed in the conversion of CH x and C to CO. Net carbon formation becomes a problem when the CH 4 dissociation and CO 2 activation steps are out of balance. Considering the current status of catalyst development and the likely future large-scale applications for CO 2 /CH 4 reforming, significant scope exists for further work in optimising both catalysts and reactor design for this reaction.

A field study was conducted to evaluate the effects of newsprint (noncomposted ground newsprint) applied with different nitrogen (N) sources on corn (Zea Mays L.) growth, yield, and soil chemical properties. The soil was a Wickham fine sandy loam (Typic Hapludults). Newsprint was applied at 2.44 kg C/m2 soil and uniformly incorporated to a depth of 10 to 15 cm. Ammonium nitrate, urea, anhydrous ammonia or poultry litter were the N sources used to adjust the C:N ratio of the newsprint to ≤ 30:1. Nutrient imbalance induced by newsprint was observed in corn during the early growing season, but at 40 to 50 days after emergence growth had resumed and biomass produced per day was not affected by N source. When newsprint was applied with anhydrous ammonia, seedlings were severely stunted, biomass production was reduced by 75 percent and yield decreased by 72 percent, when compared to anhydrous ammonia applied without newsprint. When corn was sidedressed with urea or ammonium nitrate, the apparent phytotoxicity o...

The current emissions of CO2 to the atmosphere through man-made activities are outlined and the options for recycling CO2 for some useful purpose, as distinct from simply storing or disposing it in an environmentally-benign manner, are discussed. It is shown that for CO2 recycling to have any significant impact on reducing emissions of this gas, it must form part of some large-scale energy conversion process which is based on a non-fossil-fuel energy source such as solar or nuclear energy. Since the quantities of undiluted CO2 available for recycling are relatively small, the cost of recovering CO2 from sources such as power station flue gas must be taken into account in the overall CO2 recycling/energy conversion scheme.

Families from the linkage panel of Centre d’Etude du Polymorphisme Humain have been used to generate a linkage map containing 68 loci; 13 genes, 33 di- and 4 tetranucleotide repeats, one oligonucleotide ligation assay (OLA), and 17 RFLPs. This map integrates markers from several previous maps, and has undergone further error checking. 43 loci have been placed with odds of 1000:1 or greater, five with odds of 100:1, with an average interval of 3.5 cM. An additonal 20 loci have been placed within defined intervals.

A greenhouse pot study was conducted with a Wynnville sandy loam surface soil to determine the influence of application rates of poultry litter (PL) on growth and nutrient uptake of collard (Brassica oleracea, Acephata Group L., cv. Champion), and the residual effects of PL on growth and nutrient uptake of cabbage (Brassica oleracea, Capitata Group L., cv. Rio Verde). PL at 0, 13, 26, 53, and 106 g·kg–1 was incorporated into limed (pH 6.5) and nonlimed (pH 5.2) soil. Collard plants were grown for 52 days. The residual effects of PL were evaluated by growing three successive crops of cabbage without further application of PL (total 218 days). Collard plants were severely damaged or killed within 7 days after transplanting when the application rate of PL exceeded 26 g·kg–1 soil. Maximum dry matter yield of cabbage shifted from 26 to 106 g PL/kg soil during three successive crops. After four successive growth periods, 6% to 37% of N, 3% to 62% of Ca, 20% to 120% of K, 5% to 60% of Mg, and 3% to 25% of P added through PL was removed by plants. The decrease in water-extractable K accounted for the decrease in the soil salinity. Our results suggest that application rates of PL ≥ 53 g·kg–1 soil can result in elevated levels of salts and NH3 in soil, which can produce severe salt stress and seedling injury.

Acid subsoils and tillage pans limit crop yields on sandy soils of the Southern Coastal Plain of the United States. Studies were conducted for 3 years on two soils with acid subsoils and tillage pans to determine the effect of starter fertilizer (22 kg N, 10 kg P ha −1 and fluid lime (1350 kg ha −1 ) placement with in-row tillage methods on growth and yield of grain sorghum ( Sorghum bicolor (L.) Moench) grown in a conservation-tillage system. Fertilizer and lime were applied in factorial combinations in the in-row subsoil channel, in a narrow (4-mm) slit 18 cm below the tillage pan (slit-tillage), or 7 cm to the side of the row incorporated 7 cm deep. Slit-tillage was as effective as subsoiling in two of the four tests where plant growth and grain yield responded to deep tillage. Of the other two tests where there was a response to deep tillage, slit-tillage resulted in a 6% decrease in grain yield compared to subsoiling in one test, and an 8% yield increase in the other. Starter fertilizer placement was not critical, but response to starter fertilizer occurred only when deep tillage, either in-row subsoiling or slit-tillage, was used in conjunction with the fertilizer. Starter fertilizer consistently increased early-season plant growth; however, yield response to starter fertilizer was highly dependent on rainfall. Starter fertilizer application increased yield in only one of five tests. There was no benefit from injecting lime.

The oxidative coupling of methane has been conducted in 30 and 60mm dia. fluidised-bed reactors. Methane conversions as high as 40% were achieved at isothermal conditions using methane/oxygen mixtures without diluents. At the same contact time the two reactors had similar selectivities to hydrocarbons. At 850°C the hydrocarbon selectivity decreased dramatically with increasing contact time but this effect was much less severe at lower temperatures. Axial gas concentration profiles through the catalyst bed in the 60mm reactor indicated that at 850°C there was a rapid consumption of oxygen and formation of products in the bottom section of the bed followed by a net loss of hydrocarbon in the oxygen-free zone. This loss was due to carbon formation on the catalyst which was circulated back to the oxygen-containing zone of the bed where the carbon was combusted.

Publisher Summary CSIRO has completed a major project to demonstrate a solar thermal-fossil energy hybrid concept for generating solar-enriched fuels and electricity with potential for high thermal efficiencies and for greatly reduced CO2 emissions. This concept features: reforming of CH4-containing gases using concentrated solar energy to generate a mixture of CO and H2 suitable for use as a fuel, metallurgical reductant or as a chemical feed stock. Another feature is further conversion of the gas to H2 and CO2 followed by recovery of CO2 in a concentrated form, as required for any subsequent CO2 disposal or utilization scheme; and further purification of gas to produce H2 for use in advanced electricity generation systems such as fuel cells and turbines. Integrated mode of operation was conducted producing PEMFC quality H2. With much improved dish mirrors, tracking algorithm, and an energy efficient reformer, solar steam reforming at 136% design feed was achieved. This indicates strong potential for further improvements resulting in commercial application of the proposed Solar Thermal Fossil Energy Hybrid System.

Publisher Summary The catalytic oxidative coupling of methane under the practical operating conditions relevant to an industry-scale natural gas conversion process will almost certainly require some form of fluidized-bed reactor to cope with the large amount of heat released by this highly exothermic reaction. To this end, CSIRO's reaction engineering research on methane oxidative coupling has focused on studying this reaction in small-scale fluidized-bed reactors, which have been operated under the practical conditions of using oxygen (rather than air) as oxidant in the absence of any diluents. Laboratory-scale bubbling fluidized-bed reactors have been operated at both atmospheric and elevated pressures using high performance methane oxidative coupling catalysts developed by CSIRO. This work has generated a unique set of experimental data which has been used to identify mechanisms governing the overall performance of fluidized-bed reactors and to develop an empirical model describing the influence of key reactor operating variables on this reaction. This chapter outlines some of the major findings of this reaction engineering research and illustrates how the model can be used to successfully describe the effect of a key parameter—namely, pressure—on the performance of one particular catalyst in the fluidized-bed reactor.

Publisher Summary The reforming of CH 4 with CO 2 to produce synthesis gas with a H 2 /CO ratio of around 1 has to date had no commercial application by itself. It has, however, been used in conjunction with the widely applied stedCH 4 reforming process when the H 2 CO ratio of the product gas is required to be less than that generated by steam reforming alone. In certain potential applications (e.g. energy storage and transmission) CO 2 /CH 4 reforming has a number of advantages over steam reforming, and is likely to become an increasingly important industrial reaction in the future. This chapter reviews the current status of research on the development of catalysts and reactor technology for CO 2 /CH 4 reforming. It also outlines the current and future applications for CO 2 /CH 4 reforming with particular emphasis on its impact on future energy conversion technologies and implications for achieving reductions in Greenhouse Gas emissions.

Skeletal muscle function of 15 patients with myotonic dystrophy (dystrophia myotonica, DM) was investigated using 31P magnetic resonance spectroscopy to evaluate bioenergetics and intracellular pH at rest and during exercise and recovery. Results from DM patients, normal controls and mitochondrial myopathy patients were compared in order to assess the possible contribution of abnormal mitochondrial metabolism to muscle dysfunction in DM. In resting DM muscle, intracellular pH (pHi) was normal, but there were significant elevations in the concentration ratios of P i ATP , phosphomonoesters/ATP and phosphodiesters/ATP. In patients with the most severe exercise intolerance the phosphocreatine ATP ratio was also reduced. Resting muscle of 11 mitochondrial myopathy patients showed similar changes to those of the most exercise-intolerant DM patients. In exercising DM muscle, energy stores were rapidly depleted as in mitochondrial myopathy. Muscle acidified in all subjects, but in DM the decrease in pHi was less than in normal muscle. Recovery half-times for phosphocreatine, Pi and ADP were normal in DM but slow in mitochondrial myopathy. The initial rate of phosphocreatine repletion after exercise was rapid in DM, consistent with high [ADP], but slow in mitochondrial myopathy in spite of elevated [ADP]. Because recovery is an oxidative process, we conclude that there was no decrease in the oxidative capacity of the muscles in this group of DM patients. In the subjects in whom it could be measured, the rate of recovery of intracellular pH was greater in the 3 DM patients (0.14, 0.15 and 0.16 U/min) than in the 7 normal controls (0.08–0.12 U/min, mean 0.10). The results do not rule out a minor abnormality in glycogenolysis, but they suggest that the failure to acidify normally during exercise is probably due to rapid proton efflux.

Summary The ‘OXCO’ conceptual process for natural gas conversion via methane oxidative coupling is outlined. Results are presented from studies of methane coupling in fluidised-bed reactors in which methane conversion of 24% and hydrocarbon selectivity of 70% have been achieved at 850°C. Ethane injection into the oxygen-free zone of the fluidised-bed resulted in 71% pyrolytic conversion of ethane with 93% selectivity to unsaturates. These results demonstrate that methane coupling and the pyrolysis of higher alkanes can be efficiently combined within a single fluidised-bed reactor forming the basis of the “OXCO” process for the total utilisation of natural gas. Mass balance calculations based on these results indicate that the process has the potential for converting Australian natural gas to unsaturates with an overall selectivity in excess of 85%.

Recycled paper pellets in the bottom of containers were evaluated for retention of N from container leachate. `Formosa' azalea were transplanted on 15 Apr. in 2.8-L containers in a pine bark/peat substrate (3:1; v/v). Treatments included paper (0 or 2.5 cm depth) in the bottom of containers and two rates of Osmocote 18–6–12 (0.68 kg or 1.36 kg N/yd3). Immediately after transplanting, plants were topdressed with 3.2 g of 12–4–6 fertilizer. Data collected included leachate samples every 2 weeks for NO3-N and NH4-N levels and destructive sampling every 4 weeks for shoot dry weight, foliar N, and total paper N. Nitrate-N and NH4-N leachate concentrations were reduced with the 0.68 kg N/yd3 fertilizer rate and with paper. For example, 28 days after planting (DAP) NO3-N leachate concentrations were reduced 36% with the 0.68 kg N/yd3 fertilizer rate and 46% with paper in the bottom of containers. NH4-N in the leachates was reduced 53% with the 0.68 kg N/yd3 fertilizer rate and 59% with paper. Azalea shoot dry weight was not affected by paper or fertilizer rate up to 112 DAP; however, as the study progressed, plants with paper in the bottom of containers grew larger than plants in no paper treatments (29% at 168 DAP, 31% at 196 DAP). Total N absorbed by paper was not affected by fertilizer rate, and peaked at 168 DAP [980 (0.68 kg N/yd3) to 1066 (1.36 kg N/yd3) mg per container, or 41% – 28% of applied N], after which it began to decline. This decline in paper N was associated with greater growth of azalea with paper.

Blue color development in Hydrangea macrophylla is usually accomplished by applying Al as an alum drench. Drenches are applied during forcing 10–14 days after transplanting at a rate of 17,500 mg·L-1. Cultivars Blue Wave and Nikko Blue were used to evaluate if the Al contained in waste paper can provide the necessary Al for blue flower development. Two waste paper forms, pelletized and crumble, were used as surface mulches and as media amendments. The amendments were incorporated into the media at transplanting and mulches were applied either at transplanting or 28 days later. Alum drenching was initiated at transplanting as a control. Leachates were collected weekly using the VTEM. Total Al, electrical conductivity, and pH were determined on all samples. All waste paper treatments resulted in pink flowers in both cultivars. Leachate pH, from plants in this test, was >6.5. Aluminum concentration was greater than the 15 mg·L-1 Al needed for blue color development in flowers, but Al concentration decreased with time. Control of pH at the waste paper surface and in the media is critical for increasing the availability of labile Al for uptake by hydrangea.

Excessive moisture is a problem in evaluating recycled paper products as mulch to replace other common mulch materials and in landscape and container uses. To isolate the water associated with soil and/or media, two recycled paper products, pellets or crumble, were used as mulches in trade gallon containers in a greenhouse. Pine bark, pellets, and crumble needed to obtain standard mulch depth were enclosed in plastic mesh. These mulches were placed in containers that contained 1 kg of a 7 pine bark : 1 sand media. All containers were saturated with tap water for 24 hours. Mulches were placed on each container and allowed to drain for 1 hour. Weights of media, mulch, and media and mulch were obtained every 24 hours for a total of 312 hours. Water content of the media was not influenced by any of the mulch treatments. Water content of the paper products was increased by a factor of two. Pine bark mulch water content was zero 96 hours after an initial dry down cycle began, while the water content of pellet and crumble were 100 and 90 cm of water. Total water content of the media plus the mulch was increased by 30% to 35% when compared to pine bark mulch alone. However, the increase was associated with the water content of the waste paper mulch.

Two studies were conducted to evaluate recycled newspaper mulch for landscape plantings. In the first study, two paper products (pellets and crumble) were tested at three depths. Application of either 25 or 50 mm provided excellent control of prostrate spurge. Of the four annuals grown, ageratum exhibited severe stunting of roots and shoots. In the second study, three annual species were mulched with the two recycled paper products applied at 25 mm each and adjusted with P at 0, 3.75, or 7.5 ppm to bind excess Al. When no P was added, ageratum growth was about half that of the control plants. Addition of P at either rate resulted in similar growth compared to control plants. Marigold and geranium were less affected by recycled paper mulch; however, when P was added growth was always similar to nonmulched control plants.

Soils of the peach growing region of the Southeastern Coastal Plain are highly leached and excessively acid, with inherently low concentrations of subsoil magnesium (Mg). A greenhouse experiment was conducted to determine the effects of varying Mg concentrations at low pH on growth and Mg uptake of three peach seedling cultivars commonly used as rootstock in the region. Seedlings of ‘Lovell’, ‘Elberta’, [Prunus persica (L.) Batsch] and ‘Nemaguard’ [Prunus persica (L.) Batsch X Prunus davidiana Carriere] were grown for 36 days in nutrient solution containing 9, 21, 42, 84, 167, 333, and 667 μM Mg. Magnesium concentration in solution did not increase lateral length, number of laterals, trunk cross‐sectional area, or root volume. All terminal growth responses were cultivar related. Magnesium concentration in the leaves, stems, and roots were increased either by quadratic or cubic relationship with solution Mg concentration while Mg uptake rate was increased linearly with solution Mg concentration wi...