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Neuromodulation mediated by synaptically released endogenous transmitters acting in G-protein-coupled receptors (GPCRs) is slow primarily because of multistep downstream signaling. What is less well understood is the spatial and temporal kinetics of transmitter and receptor interaction. The present work uses the combination of the dopamine sensor, dLight, to detect the spatial release and diffusion of dopamine and a caged form of a D2-dopamine receptor antagonist, CyHQ-sulpiride, to rapidly block the D2 autoreceptors. Photoactivation of the CyHQ-sulpiride blocks receptors in milliseconds such that the time course of dopamine/receptor interaction is mapped onto the downstream signaling. The results show that highly localized release, but not dopamine diffusion, defines the time course of the functional interaction between dopamine and D2 autoreceptors, which determines downstream inhibition.

G Daniel Brooks The Asthma and Allergy Center, Bellevue, NE, USACorrespondence: G Daniel BrooksThe Asthma and Allergy Center, 3503 Samson Way, Suite 108, Bellevue, NE 68123, USATel +1-402-592-2055Fax +1-402-592-2419Email gdbrooks@asthmaandallergycenter.comAbstract: Uncontrolled asthma continues to be a problem for many patients with moderate-to-severe allergic asthma. Dupilumab, which blocks the receptors for interleukin-4 and interleukin-13, has been effective in reducing asthma exacerbations, improving forced expiratory volume in one second (FEV1), and reducing oral corticosteroid use. When selecting patients for dupilumab, it is important to consider entry criteria for the original studies, subgroups that have responded best, and the presence of comorbid diseases that may also respond to dupilumab. Factors that were considered when selecting patients likely to respond to dupilumab in asthma studies include: failure of moderate or high dose inhaled steroids in combination with an additional controller medication, baseline FEV1 reversibility of 12% or greater, and Asthma Control Questionnaire > 1.5. The baseline characteristics that predicted a better response to dupilumab included blood eosinophils > 150 cells/mm3 and fractional exhaled nitric oxide > 25 parts per billion. Comorbidities that may also respond to treatment with dupilumab include atopic dermatitis, chronic rhinosinusitis, and allergic rhinitis. A combination of these factors should be considered when selecting the patients most likely to benefit from dupilumab.Keywords: allergic asthma, dupilumab, eosinophils, nitric oxide, comorbidity

The dopamine D2 receptor has two splice variants, D2S (Short) and D2L (Long). In dopamine neurons, both variants can act as autoreceptors to regulate neuronal excitability and dopamine release, but the roles of each variant are incompletely characterized. In a previous study we used viral receptor expression in D2 receptor knockout mice to show distinct effects of calcium signaling on D2S and D2L autoreceptor function (Gantz et al., 2015). However, the cocaine-induced plasticity of D2 receptor desensitization observed in wild type mice was not recapitulated with this method of receptor expression. Here we use mice with genetic knockouts of either the D2S or D2L variant to investigate cocaine-induced plasticity in D2 receptor signaling. Following a single in vivo cocaine exposure, the desensitization of D2 receptors from neurons expressing only the D2S variant was reduced. This did not occur in D2L-expressing neurons, indicating differential drug-induced plasticity between the variants.

Our aim was to investigate if deoxyribonuclease (DNase) 1 is a potential therapeutic agent to reduce pathogenic effects of cigarette smoke exposure in the lung. Cigarette smoke causes protease imbalance with excess production of proteases, which is a key process in the pathogenesis of emphysema. The mechanisms responsible for this effect are not well-defined. Our studies demonstrate both in vitro and in vivo that cigarette smoke significantly increases the expression of neutrophil and macrophage extracellular traps with coexpression of the pathogenic proteases, neutrophil elastase and matrix metalloproteinases 9 and 12. This response to cigarette smoke was significantly reduced by the addition of DNase 1, which also significantly decreased macrophage numbers and lung proteolysis. DNase 1, a treatment currently in clinical use, can diminish the pathogenic effects of cigarette smoke.

Ferrous-calcium-silicate (FCS) based slag has been used in the copper industry over the last two decades. The FCS slag has also been used in a secondary copper processing such as in black copper smelting which has different operation conditions compared to that of typical primary copper processing. In the process, a variety of copper bearing scraps from sources such as industrial waste, consumer waste and electronic waste (e-waste) are used. The valuable metals in these secondary resources are distributed in different phases during the process. Understanding the behaviour of the valuable elements at the relevant conditions is vital for optimizing the process and to maximize the recovery of the elements. In this study, we investigated the structure of Ge-containing FCS-based slag at different conditions (oxygen partial pressure and temperature) using Fourier-Transform Infrared (FTIR) spectroscopy to explore the effect of the polymerization on the behaviour of the valuable element Ge in the slag. It was found that experimental parameters significantly influence the slag structure, and therefore, the partitioning of Ge in the slag. A correlation between the distribution ratio of Ge and the slag structure has developed in the current study.

© 2017, Springer Japan. In this paper, a detailed thermodynamic analysis of processing of electronic waste (e-waste), particularly printed circuit boards (PCB), through secondary copper recycling (black copper smelting), was carried out. The mass balance flowsheets of two scenarios, i.e., the case of secondary copper recycling with (SCE1) and without (SCE2) addition of PCBs, have been developed and compared. From the perspective of recovery of copper (Cu), gold (Au), and silver (Ag); the thermodynamic analysis predicted that the process conditions at temperature of 1300 °C and oxygen partial pressure (pO2) of 10–8 atm are suitable for PCB processing through secondary copper smelting route. Under these conditions, no solid phases were predicted to form when the PCB addition is below 50 wt%. High PCB addition was predicted to produce high volume of slag in the process and more pollutants in the gas phase (Br-based gaseous compounds). The chemistry of the slag was also predicted to change that is shifting the liquidus temperature to a higher value due to the presence of aluminium (Al), silica (SiO2), and titanium dioxide (TiO2) in the feed coming from the PCB. The carbon content of the PCB potentially supplies additional heat and reductant (CO) in the process hence can partially replace coke in the feed material. The predicted recoveries of copper (Cu), gold (Au), and silver (Ag) from e-waste were 83.3, 96.5, and 88.5 wt% respectively.

In this paper, experimental investigation on the carbosulphidation of alumina (Al2O3) for aluminium (Al) production and the sodiothermic reduction of aluminium sulphide (Al2S3) are presented. Hydrogen sulphide (H2S) was used as a reductant and source of sulphur. This work is the second of two-parts paper series. The experimental investigations of the Stage-1 process (Al2O3 carbosulphidation) were carried out at 1100–1600°C using a laboratory scale horizontal tube resistance-furnace. H2S gas, diluted with argon (5% H2S and 95% Ar), was reacted with pellets of a mixture of γ-Al2O3 and C powders (1:6 molar ratio) to produce Al2S3. The effects of gas injection rate, pelletizing pressure, temperature and reaction time on the conversion of Al2O3 to Al2S3 were investigated. The X-ray diffraction results confirmed the formation of Al2S3(s) in the reaction product above 1400°C. The conversion of Al2O3 to Al2S3 was found to be 99.5% at 1600°C and 12 h. The kinetics analysis of alumina sulphidation using Ginstling-Brounshtein diffusion model suggested the overall reaction was controlled by the diffusion of H2S gas through the reaction product (liquid Al2S3). The activation energy of the alumina sulphidation reaction was calculated to be 148.5 kJ mol−1. It has also been demonstrated in this study that Al can be extracted from Al2S3 by sodiothermic reduction using Na or NaH. In the case of Na, a level of Al conversion of 75% has been observed for reaction at 290°C.

© 2017 Institute of Materials, Minerals and Mining and The AusIMM Published by Taylor & Francis on behalf of the Institute and The AusIMMA novel multi-stage Al production through a carbosulphidation of Al2O3, followed by a sodiothermic reduction of Al2S3, was proposed. In Stage-1, alumina (or bauxite) is reduced to Al2S3 in the presence of carbon and H2S. In Stage-2, Al2S3 is reduced to Al through reactions with Na or NaH. The thermodynamic analysis predicted Al2S3 to be the main intermediate Al-compound when H2S is reacted with Al2S3 and C at 1000-2000°C at 1 atm. Al2S3 formation was predicted to be low at 1100-1300°C at 1 atm (0.1 moles/mole Al2O3) but increased with increasing temperature (0.96 moles/mole Al2O3 at 1800°C). The thermodynamic analysis of sodiothermic reduction predicted that Al metal can be extracted from Al2S3 below 800°C at 1 atm. The Na2S produced can be hydrolysed to form H2S and NaOH. H2S can be re-used and the Na can be reproduced from NaOH and put back into the process.

Our aim was to investigate if deoxyribonuclease (DNase) 1 is a potential therapeutic agent to reduce pathogenic effects of cigarette smoke exposure in the lung. Cigarette smoke causes protease imbalance with excess production of proteases, which is a key process in the pathogenesis of emphysema. The mechanisms responsible for this effect are not well-defined. Our studies demonstrate both in vitro and in vivo that cigarette smoke significantly increases the expression of neutrophil and macrophage extracellular traps with coexpression of the pathogenic proteases, neutrophil elastase and matrix metalloproteinases 9 and 12. This response to cigarette smoke was significantly reduced by the addition of DNase 1, which also significantly decreased macrophage numbers and lung proteolysis. DNase 1, a treatment currently in clinical use, can diminish the pathogenic effects of cigarette smoke.

The slag-to-metal distribution ratios of palladium (Pd), Ls/mPd, in the range of oxygen partial pressure (pO2) from 10−10 to 10−7 atm at 1473 K to 1623 K (1200 °C to 1350 °C); distribution ratios of tantalum (Ta), Ls/mTa, in the range of pO2 from 10−16 to 10−12 atm at 1673 K and 1873 K (1400 °C and 1600 °C), have been determined in this study. The Ls/mPd in FeOx-CaO-SiO2-MgO and copper at 1573 K (1300 °C) and pO2 = 10−8 atm is dependant strongly on basicity of slag, i.e. (CaO + MgO)/SiO2 or optical basicity. The current results suggest that Pd presents in the FeOx-CaO-SiO2-MgO slag predominantly as Pd2+. The activity coefficient of PdO in the slag at 1573 K (1300 °C) and pO2 = 10−8 atm was calculated to be in the range of 3.89 × 10−3 to 2.63 × 10−2. The Ls/mPd was also found to increase with increasing of pO2 and with decreasing of temperature. It was observed that Ta mostly partition to slag phase and very small amount of Ta was found in liquid copper at the high temperature and reduced condition studied. It can be suggested that to promote recovery of palladium from Pd-containing e-waste, a slag with lower silica content and basic flux based, high temperature with reducing atmosphere, is highly desired particularly in secondary copper smelting.

Declining grade of primary ores and resource efficiency have led us to process more alternative metal resources such as e-waste. One of the processing routes for extracting valuable metals from e-waste is through the black copper smelting. However, the underlying knowledge of the thermodynamics behaviour of the valuable metals contained in e-waste during smelting are limited which prevent us from developing an optimised process to recover all the metals. These different metals clearly will have different favourable conditions for their extraction. To illustrate this, the distribution behaviour of germanium (Ge) and palladium (Pd) between liquid copper and ferrous-calcium-silicate slag during black copper smelting was analysed. It was demonstrated that oxygen partial pressure and slag composition affect the partitioning of these metals to the copper phase and the favourable slag chemistry for recovering these metals is opposing. Considering the available thermodynamic data of these metals, an analysis for the optimum conditions is presented.

© 2017 Elsevier B.V. This study provides an environmental impact assessment of the black copper smelting route for the processing and recovery of copper and other valuable metals such as gold and silver from waste printed circuit boards (PCB). Thermodynamic based analysis was conducted to simulate the recycling process and a life cycle assessment was carried out to estimate and compare the environmental impact of the two scenarios: (1) recycling of precious metal out of waste PCBs through secondary copper smelting (Electronic Waste Processing, EWP); and (2) secondary copper recycling without adding electronic waste to the feed (SCR). The results of the study revealed that environmental impacts of using e-waste along with low-grade copper scrap in existing smelters to recover precious metals are dependent on the distance the material feed travels to the smelter and the means of electricity supplying the smelter. It is also found that the impact of the EWP scenario for climate change, freshwater eutrophication, and fossil depletion is significantly higher than those obtained from the SCR scenario and it is mainly because the metal and oxide dust in former scenario needs to be further refined to recover metals such as nickel, zinc and lead. The results also confirm that 10% cut in electricity usage in EWP scenario, has the higher environmental benefit in almost all dominant categories.

In this paper, we aim to investigate the dynamics and existence of periodic solutions of a state-dependent impulsive model for continuous flow bioreactors. In this model, the Monod’s growth rate is employed and an impulsive control strategy is used to control the quantity of microorganisms. Our study shows all solutions of the model are bounded; and the order-1 periodic solution exists under certain conditions. At the end of this paper, numerical simulations have been carried out to demonstrate our theoretical results and the performance of the bioreactor.

This presentation will report the processing of e-waste and extraction of the valuable metals through secondary copper smelting route (black copper smelting), as shown in Figure 1. The rationale for choosing the selected route will be explained. The approach taken in the study includes combined thermodynamic and process flowsheet modelling followed by economic as well as environmental impact assessments. The results of the study confirm the need for further study on the behaviour of various elements for the modelling for improvement of the process. The result from the economic study also showed that the selected process route is economically viable. The largest impact was found to be from the variation of the raw material cost, followed by the interest rate on borrowing capital. It was found that the minimum plant capacity for the process to be still economically viable is predicted to be 30,000 tonnes/annum.

Wastes of electronics and electrical equipment (WEEE) or simply e-wastes contain many valuable elements that include base metals (Cu, Fe, Pb, Al), precious metals (Au, Ag, Pt, Pd), other metals (Sn, Se, Te, Ta, Co, In, Ru, etc); as well as hazardous elements. Sustainable extraction of the valuable elements from e-waste is challenging due to the complexities of the materials and associated processing routes. There have been a number of processing and extraction techniques developed at laboratory level and few are implemented in industrial practices [1]. The processes implemented at industrial scale are mainly based on an improved combination of traditional extractive metallurgy processes (for example a combined pyrometallurgy, hydrometallurgy and electrometallurgy processes). Although practiced at industry scale, these processes and processing routes are far from optimised. Development of new technologies and/or improvement of the existing practices are still needed. Some of the barriers for improvement include: lack of fundamental knowledge (behaviour of all of these elements, which are governed by their solution thermodynamics); limited sound technoeconomic analyses; as well as limited understanding on the environmental impact of the different processing routes.

The distribution ratio of germanium (Ge), (Formula presented.) during equilibrium reactions between magnesia-saturated FeOx-CaO-SiO2 (FCS) slag and molten copper has been measured under oxygen partial pressures from 10−10 to 10−7 atm and at temperatures 1473 to 1623 K (1200 to 1350 °C). It was observed that the Ge distribution ratio increases with increasing oxygen partial pressure, and with decreasing temperature. It was also observed that the distribution ratio is strongly dependent on slag basicity. The distribution ratio was observed to increase with increasing optical basicity. At fixed CaO concentration in the slag, the distribution ratio was found to increase with increasing Fe/SiO2 ratio, tending to a plateau at (Formula presented.) = 0.8. This behavior is consistent with the assessment of ionic bond fraction carried out in this study, and suggested the acidic nature of germanium oxide (GeO2) in the slag system studied. The characterisation results of the quenched slag suggested that Ge is present in the FeOx-CaO-SiO2-MgO slag predominantly as GeO2. At 1573 K (1300 °C) and (Formula presented.) = 10−8 atm, the activity coefficient of GeO2 in the slag was calculated to be in the range of 0.24 to 1.50. The results from the current study suggested that less-basic slag, high operating temperature, and low oxygen partial pressure promote a low Ge distribution ratio. These conditions are desired for maximizing Ge recovery, for example, during pyrometallurgical processing of Ge-containing e-waste through secondary copper smelting. Overall, the thermodynamics data generated from this study can be used for process modeling purposes for improving recovery of Ge in primary and secondary copper smelting processes.

Waste of electronics and electrical equipment (WEEE or e-waste) can be viewed as a resource for metals, as it does not only contain the common metals like iron (Fe), aluminium (Al), lead (Pb) and copper (Cu) but also traces of precious and rare elements such as gold (Au), silver (Ag), tin (Sn), selenium (Se), tellurium (Te), platinum (Pt), palladium (Pd), tantalum (Ta), cobalt (Co) and indium (In). The recovery of these trace elements is vital, not just because it has high commercial values, but also for resources efficiency. One of the existing industrial routes for processing of e-waste is through the primary and secondary Cu smelting processes. During these processes, the trace elements are distributed in different phases, i.e. in metal/matte, slag and gas. Different elements have different thermodynamic properties that govern the partitioning behaviour during the process. There has been a number of studies on the distribution behaviour of the trace elements relevant to primary Cu smelting (extraction of metals from virgin ores). However, there are only limited thermodynamics data relevant to secondary Cu smelting (extraction of metals from secondary/recycled sources). This paper reviews the thermodynamics data relevant for recovering the trace valuable elements from the primary Cu as well as secondary Cu smelting. These data and knowledge provide the basis for determining the optimum conditions favourable for recovering the trace valuable elements in e-waste through the industrial Cu pyrometallurgical processing.

D2 autoreceptors regulate dopamine release throughout the brain. Two isoforms of the D2 receptor, D2S and D2L, are expressed in midbrain dopamine neurons. Differential roles of these isoforms as autoreceptors are poorly understood. By virally expressing the isoforms in dopamine neurons of D2 receptor knockout mice, this study assessed the calcium-dependence and drug-induced plasticity of D2S and D2L receptor-dependent G protein-coupled inwardly rectifying potassium (GIRK) currents. The results reveal that D2S, but not D2L receptors, exhibited calcium-dependent desensitization similar to that exhibited by endogenous autoreceptors. Two pathways of calcium signaling that regulated D2 autoreceptor-dependent GIRK signaling were identified, which distinctly affected desensitization and the magnitude of D2S and D2L receptor-dependent GIRK currents. Previous in vivo cocaine exposure removed calcium-dependent D2 autoreceptor desensitization in wild type, but not D2S-only mice. Thus, expression of D2S as the exclusive autoreceptor was insufficient for cocaine-induced plasticity, implying a functional role for the co-expression of D2S and D2L autoreceptors.

Ground-based millimeter and sub-millimeter telescopes are attempting to image the sky with ever-larger cryogenically-cooled bolometer arrays, but face challenges in mitigating the infrared loading accompanying large apertures. Absorptive infrared filters supported by mechanical coolers scale insufficiently with aperture size. Reflective metal-mesh filters placed behind the telescope window provide a scalable solution in principle, but have been limited by photolithography constraints to diameters under 300 mm. We present laser etching as an alternate technique to photolithography for fabrication of large-area reflective filters, and show results from lab tests of 500 mm-diameter filters. Filters with up to 700 mm diameter can be fabricated using laser etching with existing capability., Comment: 6 pages, 5 figures. Presented at the 15th International Workshop on Low Temperature Detectors

Extranasal sites are common reservoirs of Staphylococcus aureus colonization and may be relevant for methicillin-resistant S. aureus (MRSA) screening and infection control strategies. The objective here was to determine whether inguinal specimens could also be screened using Xpert SA Nasal Complete assay for MRSA. Results were compared to broth enrichment culture. Among 162 consented adults seeking care in the emergency department for cutaneous abscesses, inguinal specimens were found positive for MRSA more often than nares specimens, 24% and 26% by PCR or culture, respectively, compared to 19% each by PCR or culture. Overall, 6% of adults colonized with MRSA would have been missed by nares screening alone. Compared to culture, Xpert SA Nasal Complete assay demonstrated sensitivity and specificity of 89% and 97%, respectively, for detecting nares and/or inguinal MRSA colonization. In conclusion, inguinal specimens were a more common reservoir for MRSA than nares specimens in this population of patients.

This book provides a comprehensive insight into the multilayered effects experienced by directly affected victims and their indirectly affected family members following terrorist incidents and other world disasters. Chapters draw primarily on interviews with fifty victims of the Bali bombings, but also consider terrorist incidents including the London and Boston bombings, and disasters such as the Boxing Day tsunami and the Fukushima nuclear disaster. The book provides a detailed exploration of experiences and perceptions of those involved in the traumatic events, as well as their families, emergency response teams and community volunteers. Chapters discuss community responses to major incidents, appropriate non-medical models of intervention and vulnerable groups that may require special attention. The findings and analysis presented contribute to our understanding of the multilayered effects of terrorism on victims of all levels, and the importance of a planned and informed response, which includes the local community and its wealth of pre-existing resources. Terrorism, Trauma and Psychology: A multilevel victim perspective of the Bali bombing will be key reading for researchers and academics in the fields of social and clinical psychology, as well as scholars of victimology and terrorism studies.

The production of Al from its ores at present relies on the Bayer (alumina production) and the Hall- Heroult (Al production) process. The cost associated with alumina production and apparent disadvantages of the Hall-Heroult process have led to intensive research to find alternative routes for Al production. The direct carbothermal reduction process has been thoroughly investigated as an alternative technique. Another alternative includes the indirect carbothermal reduction route where alumina (or aluminous ores) is first reduced to intermediate Al compounds before reduced further to Al. The present study reviews and provides systematic thermodynamic analyses of alternative Al production routes. In this paper (Part 1), a comprehensive review of alternative Al production techniques focusing on the indirect carbothermal reduction routes is presented. These include carbochlorination, carbonitridation and carbosulphidation routes for the formation of intermediate Al compounds, followed by various Al extraction processes.

Aim: To examine the role of deregulated gp130 signalling in the development of lung tumours and cancer-related cachexia in two models of lung cancer. Method(s): We used the gp130F/F (FF) mouse which carries a knock-in mutation in gp130, the critical co-receptor for the IL-6 cytokine family. These mice display elevated IL-6 levels and hyper-activated Stat3 in the absence of gp130-mediated PI3K/Akt and Mapk signalling. Two separate models were undertaken using FF and gp130+/+ (WT) mice commencing at 6 weeks of age. Model 1: Mice were exposed to a cigarette carcinogen (NKK) and observed over 16 weeks prior to the cellular and molecular evaluation of lung tumourigenesis. Model 2: FF and WT mice harbouring a conditionally activated oncogenic Kras allele were observed over 6 weeks after Kras activation. In addition to assessing development of lung tumours, mouse weight and muscle and fat mass were examined. Result(s): In NNK-treated animals there was a significant reduction in the number of tumours in FF mice compared to WT mice. This appeared to be independent of Stat3 as the number of tumours was unchanged from FF levels in mice with genetically normalized Stat3 levels. PI3K/Akt and Mapk pathway specific PCR arrays showed deregulation of a number of key oncogenes and tumour suppressor genes in the FF mouse suggesting a role for gp130- mediated PI3K/Akt and Mapk signalling. In the Kras model the key finding was marked weight loss in the FF mouse, with loss of both fat and lean tissue mass. This weight loss was attenuated by genetically normalizing Stat3. Conclusion(s): Our data suggest that deregulated IL-6/gp130 signalling contributes to both the development of lung cancer and its complications.

It has been widely claimed that direct and indirect carbothermic reduction of alumina for the production of aluminium have the potential to consume less energy, generate fewer perfluorocarbons and have lower total greenhouse gas emissions compared to the Hall-He´ roult process. A review of alternative aluminium production techniques focusing on the indirect carbothermal reduction routes has been presented in the Part 1 paper. In this Part 2 paper, systematic thermodynamic analyses of indirect carbothermal reduction routes are presented. These include the analyses of the Stage 1 of the process where alumina is converted to intermediate aluminium compounds before they are further reduced to aluminium metal in the subsequent stages. The results suggested that in the Stage 1, high alumina conversion at the process conditions studied can be achieved through three process routes: halide (chloride), nitride and sulphide routes. Thermodynamic analyses were also carried out for the Stage 2 where the intermediate aluminium nitride, chlorides or sulphides are reduced to aluminium through thermal dissociation, thermal disproportionation and/or electrolysis. Analysis of the results suggests aluminium may be extracted from AlN using thermal dissociation, while disproportionation and electrolysis are more suitable for AlCl3 and Al2S3.

Indirect carbothermal reduction of alumina for the production of aluminum utilizes different reducing agents to convert alumina into intermediate aluminum compounds. In the present study, the carbosulfidation route for aluminum production utilizing H2S(g) as the reductant and sulfur source has been investigated, in particular the formation of A12S3 in the first step of the process. The results of the thermodynamic analysis predicted that conversion of Al2O3(s) to Al 2S3(1) significantly increases above 1400°C at 1 atmosphere pressure. Experimental investigations were carried out at temperatures of 1100 to 1500°C using dilute H2S(g) gas in argon. The reaction products were analyzed using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), inductively-coupled plasma absorption emission spectroscopy (ICP-AES) and chemical filtration. The X-ray diffraction results confirmed the presence of Al2S3(s). Percentage of conversion from Al 2O3 to Al2S3 was found to be over 80% at 1500°C.

Indirect carbothermal reduction of alumina for the production of aluminum utilizes different reducing agents to convert alumina into intermediate aluminum compounds. In the present study, the carbosulfidation route for aluminum production utilizing H2S(g) as the reductant and sulfur source has been investigated, in particular the formation of AhS3 in the first step of the process. The results of the thermodynamic analysis predicted that conversion of Ah03(S) to AhS3(l) significantly increases above 1400°C at 1 atmosphere pressure. Experimental investigations were carried out at temperatures of 1100 to 1500°C using dilute H2S(g) gas in argon. The reaction products were analyzed using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), inductively-coupled plasma absorption emission spectroscopy (ICP-AES) and chemical filtration. The X-ray diffraction results confirmed the presence of AhS3(S). Percentage of conversion from Ah03 to AhS3 was found to be over 80% at 1500°C.

The concentrations of impurities in raw materials are increasing, with significant implications in relation to meeting customer specifications. A large fraction of the Ni and V content of coke and the Fe, Si, Ga and Zn content of alumina reports to the Al in reduction cells. Process options are reviewed for impurity control, particularly for Ni and V, and the stages in which they should be applied are discussed. Treatment in transfer crucibles is mainly for the removal of Na and Li. Na in solution can be reacted with AlF3 or MgCl2 to produce a Na salt which is then removed. MgCl2 treatment is usually employed in the holding furnace. There are two commercial crucible treatment systems, TAC and RAM. AlF3 in a filter bed form to remove Na and Ca is also possible and a bed of Al boride may be used to remove V. In-furnace refining treatment includes degassing to remove hydrogen, Na removal with MgCl2, Mg removal by chlorine fluxing or with AlF3 or SiO2 and AlB treatment to remove V. In-line gas or flux injection and in-line filtration can be applied to Ni and V where a reaction product can be created or if they are in particulate or volatile form. In-line filtration systems include ceramic foam filter tiles, rigid media filters and deep bed filters. Techniques for high-purity Al production include three-layer electrolytic refining, zone refining and fractional solidification and their combinations. Recent studies in Al refining are reviewed and techniques used for other metal systems which have potential application to Al are described including fire refining of Cu, refining of Pb, refining of metallurgical-grade Si and distillation and separation of high-vapour-pressure metals., The concentrations of impurities in raw materials are increasing, with significant implications in relation to meeting customer specifications. A large fraction of the Ni and V content of coke and the Fe, Si, Ga and Zn content of alumina reports to the Al in reduction cells. Process options are reviewed for impurity control, particularly for Ni and V, and the stages in which they should be applied are discussed. Treatment in transfer crucibles is mainly for the removal of Na and Li. Na in solution can be reacted with AlF3 or MgCl2 to produce a Na salt which is then removed. MgCl2 treatment is usually employed in the holding furnace. There are two commercial crucible treatment systems, TAC and RAM. AlF3 in a filter bed form to remove Na and Ca is also possible and a bed of Al boride may be used to remove V. In-furnace refining treatment includes degassing to remove hydrogen, Na removal with MgCl2, Mg removal by chlorine fluxing or with AlF3 or SiO2 and AlB treatment to remove V. In-line gas or flux injection and in-line filtration can be applied to Ni and V where a reaction product can be created or if they are in particulate or volatile form. In-line filtration systems include ceramic foam filter tiles, rigid media filters and deep bed filters. Techniques for high-purity Al production include three-layer electrolytic refining, zone refining and fractional solidification and their combinations. Recent studies in Al refining are reviewed and techniques used for other metal systems which have potential application to Al are described including fire refining of Cu, refining of Pb, refining of metallurgical-grade Si and distillation and separation of high-vapour-pressure metals.

Myeloid differentiation factor 88 (MyD88) and MyD88-adaptor like (Mal)/Toll-interleukin 1 receptor domain containing adaptor protein (TIRAP) play a critical role in transducing signals downstream of the Toll-like receptor (TLR) family. While genetic ablation of the TLR4/MyD88 signaling axis in mice leads to pulmonary cell death and oxidative stress culminating in emphysema, the involvement of Mal, as well as TLR2 which like TLR4 also signals via MyD88 and Mal, in the pathogenesis of emphysema has not been studied. By employing an in vivo genetic approach, we reveal here that unlike the spontaneous pulmonary emphysema which developed in Tlr4(-/-) mice by 6 months of age, the lungs of Tlr2(-/-) mice showed no physiological or morphological signs of emphysema. A more detailed comparative analysis of the lungs from these mice confirmed that elevated oxidative protein carbonylation levels and increased numbers of alveolar cell apoptosis were only detected in Tlr4(-/-) mice, along with up-regulation of NADPH oxidase 3 (Nox3) mRNA expression. With respect to Mal, the architecture of the lungs of Mal(-/-) mice was normal. However, despite normal oxidative protein carbonylation levels in the lungs of emphysema-free Mal(-/-) mice, these mice displayed increased levels of apoptosis comparable to those observed in emphysematous Tlr4(-/-) mice. In conclusion, our data provide in vivo evidence for the non-essential role for TLR2, unlike the related TLR4, in maintaining the normal architecture of the lung. In addition, we reveal that Mal differentially facilitates the anti-apoptotic, but not oxidant suppressive, activities of TLR4 in the lung, both of which appear to be essential for TLR4 to prevent the onset of emphysema.

There is significant evidence that droplets generated in steelmaking "bloat" due to the inability of gas generated from the decarburisation reaction to escape from the surface of liquid metal droplets. A model to describe this behavior was developed by Brooks, Subagyo, Coley and Pan based on their own experimental work and calculations and previous studies by Fruehan and co-workers. This approach has been successfully incorporated into an overall process model of oxygen steelmaking. A unique feature of this model is an evaluation of the decarburization kinetics of individual metal droplets in the emulsion and comparing this to the overall kinetics of oxygen steelmaking. The model suggests that the droplets become bloated and remain in the emulsion for long periods (30+ seconds). This paper evaluates the effects of droplet size and volume fraction on the bloating behavior of droplets and critically examines the repercussions of the new theory on plant design and operation.

Steelmaking is a complex process involving simultaneous multi-phase interactions, chemical reactions, heat transfer and turbulent flow patterns at high temperatures. The severe operating conditions make it difficult to make measurements and directly observe the process. Mathematical modelling has been widely used to evaluate the process and improve understanding of the system and optimise process control. Three approaches to modelling the process, equilibrium modelling to predict the equilibrium chemistry of the process, kinetic modelling to analyse rate of chemical changes throughout the process, and computational fluid modelling to understand the fluid flow in the reactor, are discussed in this paper. The governing equations and the forms of numerical computational solution techniques for these models are described, and critically examined.

Light metals have great potential for application in the automotive and aerospace industries, because of their excellent physical properties, but their use is limited by the relatively high costs of production, associated energy costs and large ecological footprint. Developments are reviewed in the production of Al, Ti and Mg with particular reference to research being carried out at CSIRO, Australia. Significant improvement to the Hall-Heroult process for Al is still achievable through advances in cell design, materials and process control. Alternative production processes include carbothermic reduction and low-temperature routes. The Kroll process for Ti is the only commercial production route, while processes under development include the Fray-Farthing-Chen and BHP Billiton electrolytic methods and the TiRO process for the direct production of Ti powder. Mg is mainly produced using the Pidgeon process although alternatives include large-scale continuous silicothermic reduction, Al reduction of magnesia or dolomite, and carbothermic reduction methods., Light metals have great potential for application in the automotive and aerospace industries, because of their excellent physical properties, but their use is limited by the relatively high costs of production, associated energy costs and large ecological footprint. Developments are reviewed in the production of Al, Ti and Mg with particular reference to research being carried out at CSIRO, Australia. Significant improvement to the Hall-Heroult process for Al is still achievable through advances in cell design, materials and process control. Alternative production processes include carbothermic reduction and low-temperature routes. The Kroll process for Ti is the only commercial production route, while processes under development include the Fray-Farthing-Chen and BHP Billiton electrolytic methods and the TiRO process for the direct production of Ti powder. Mg is mainly produced using the Pidgeon process although alternatives include large-scale continuous silicothermic reduction, Al reduction of magnesia or dolomite, and carbothermic reduction methods.

The behaviour of direct-reduced iron (DRI) fines was characterised because of their potential for injection into liquid steel to reduce its nitrogen content. Physical and chemical analysis of DRI fines samples included size analysis, chemical analysis, X-ray diffraction and simultaneous thermogravimetric and differential thermal analysis. The chemical changes during heating were also simulated using FACT thermodynamic analysis. It was found that C and O in the iron oxides reacted above 500 degrees C and that the reactions were generally completed by 700 degrees C if the C:O ratio was balanced. Samples with lower oxygen contents continued to react above this temperature, due to the reduction of gangue oxides in the DRI., The behaviour of direct-reduced iron (DRI) fines was characterised because of their potential for injection into liquid steel to reduce its nitrogen content. Physical and chemical analysis of DRI fines samples included size analysis, chemical analysis, X-ray diffraction and simultaneous thermogravimetric and differential thermal analysis. The chemical changes during heating were also simulated using FACT thermodynamic analysis. It was found that C and O in the iron oxides reacted above 500 degrees C and that the reactions were generally completed by 700 degrees C if the C:O ratio was balanced. Samples with lower oxygen contents continued to react above this temperature, due to the reduction of gangue oxides in the DRI.

Light metals have great potential for application in the automotive and aerospace industries because of their excellent physical properties but the use of Al, Ti and Mg is limited by the relatively high production costs, associated energy costs and large ecological footprint. In the case of Al, significant improvements to the Hall-Heroult process are achievable through advances in cell design, materials and process control. Possible developments include sidewall and cathode materials that are resistant to cryolite, cathodes that are wettable by molten Al, continuous carbon anodes that eliminate disturbance to the cell resulting from anode replacement and non-consumable, inert anodes. Alternative production processes include carbothermic reduction and low-temperature routes. Alternatives to the Kroll process for Ti that are being developed include the use of an electrolytic cell and direct production of Ti powder. Most Mg is currently produced using the Pidgeon process. Other possibilities are large-scale continuous silicothermic reduction, Al reduction of magnesia or dolomite and carbothermic reduction processes., Light metals have great potential for application in the automotive and aerospace industries because of their excellent physical properties but the use of Al, Ti and Mg is limited by the relatively high production costs, associated energy costs and large ecological footprint. In the case of Al, significant improvements to the Hall-Heroult process are achievable through advances in cell design, materials and process control. Possible developments include sidewall and cathode materials that are resistant to cryolite, cathodes that are wettable by molten Al, continuous carbon anodes that eliminate disturbance to the cell resulting from anode replacement and non-consumable, inert anodes. Alternative production processes include carbothermic reduction and low-temperature routes. Alternatives to the Kroll process for Ti that are being developed include the use of an electrolytic cell and direct production of Ti powder. Most Mg is currently produced using the Pidgeon process. Other possibilities are large-scale continuous silicothermic reduction, Al reduction of magnesia or dolomite and carbothermic reduction processes.

info:eu-repo/semantics/published

Pyrometallurgical processing remains more attractive than hydrometallurgical options in terms of energy use, as low-temperature routes generally consume more energy than comparable high-temperature routes. The energy efficiency of pyrometallurgical operations varies considerably but can be greater than 70% for large-scale production. Hydrometallurgical processes tend to require both extensive grinding and electrowinning; grinding has very low energy efficiencies, less than 5%, and electrowinning generally wastes energy, with overall efficiencies of less than 50%. The physical chemistry of proposed reactive ball milling processes is unclear but preliminary evaluations indicate that this processing route is likely to be very energy-intensive, involving ultrafine grinding to produce an amorphous material with high reactivity for subsequent carbothermic reduction., Pyrometallurgical processing remains more attractive than hydrometallurgical options in terms of energy use, as low-temperature routes generally consume more energy than comparable high-temperature routes. The energy efficiency of pyrometallurgical operations varies considerably but can be greater than 70% for large-scale production. Hydrometallurgical processes tend to require both extensive grinding and electrowinning; grinding has very low energy efficiencies, less than 5%, and electrowinning generally wastes energy, with overall efficiencies of less than 50%. The physical chemistry of proposed reactive ball milling processes is unclear but preliminary evaluations indicate that this processing route is likely to be very energy-intensive, involving ultrafine grinding to produce an amorphous material with high reactivity for subsequent carbothermic reduction.

Virtual reality allows the creation of computer-generated worlds within which trainees can be exposed to simulated hazardous conditions and their responses under stress tested. However, such systems often require expensive workstations and need to be programmed from scratch. The AIMS Research Unit at the University of Nottingham has produced a PC-based virtual reality application tool that allows the creation of training applications without programming. The case for virtual reality training is discussed, features of the SAFE-VR application tool outlined and examples of a pre-shift truck inspection and drill-rig operation described., Virtual reality allows the creation of computer-generated worlds within which trainees can be exposed to simulated hazardous conditions and their responses under stress tested. However, such systems often require expensive workstations and need to be programmed from scratch. The AIMS Research Unit at the University of Nottingham has produced a PC-based virtual reality application tool that allows the creation of training applications without programming. The case for virtual reality training is discussed, features of the SAFE-VR application tool outlined and examples of a pre-shift truck inspection and drill-rig operation described.

The AIMS Research Unit at the University of Nottingham is using a range of computer-aided design systems in conjunction with other 3D graphics and virtual reality packages to create easily used solutions to specific environmental problems. In the case of disused mines with potential as landfill sites, advanced computer graphics and virtual reality technology can be applied to visualising the design, assessing the impact and modifying the design before, during and after development. The real-time virtual reality experience can be extended to produce a range of interactive systems for training staff to spot and correct environmental and engineering hazards in their workplace., The AIMS Research Unit at the University of Nottingham is using a range of computer-aided design systems in conjunction with other 3D graphics and virtual reality packages to create easily used solutions to specific environmental problems. In the case of disused mines with potential as landfill sites, advanced computer graphics and virtual reality technology can be applied to visualising the design, assessing the impact and modifying the design before, during and after development. The real-time virtual reality experience can be extended to produce a range of interactive systems for training staff to spot and correct environmental and engineering hazards in their workplace.

A population of the xylem-feeding spittlebug, Neophilaenus lineatus, on blocks of natural vegetation transferred to large hemispherical chambers was studied over two generations with continuous exposure to elevated CO2 (600 ppm). The third generation was transferred from the blocks to potted Juncus squarrosus to enable measurements of fecundity. The principal food plant throughout was Juncus squarrosus. Survival of the nymphs was reduced by more than 20% in elevated CO2 relative to ambient (350 ppm) in both years of the main experiment. Elevated CO2 also delayed development by one or more nymphal instars in each year. Fecundity was not significantly affected. The C/N ratio of whole Juncus leaves was increased in elevated CO2 and the transpiration rates of the plants were reduced. These changes may have been responsible for the effect of elevated CO2 on spittlebug performance. However, other factors such as plant architecture and microclimate may also be important.

Exposure of R. crispus and R. obtusifolius to elevated CO2 (600 ppm) resulted in an increased C:N ratio of leaf tissue and greater leaf areas. Larvae of P. nigritarsis mining leaves of R. obtusifolius during exposure produced significantly bigger mines in elevated than in ambient (350 ppm) conditions. There were no significant treatment effects on pupal weight although in both host species mean weight was greater in ambient than in elevated conditions. These results are consistent with the hypothesis that insect herbivores compensate for increased C:N ratios by increased food consumption. This response by herbivores may partially offset predicted increases in plant biomass in a future high CO2 environment.

Scheme is a statically scoped and properly tail-recursive dialect of the Lisp programming language invented by Guy Lewis Steele Jr and Gerald Jay Sussman. It was designed to have an exceptionally clear and simple semantics and very few different methods of expression formation. This paper reports their unanimous recommendations augmented by committee work in the areas of arithmetic, characters, strings, and input/output. Scheme shares with Common Lisp the goal of a core language common to several implementations. Scheme differs from Common Lisp in its emphasis upon simplicity and function over compatibility with older dialects of Lisp. Contents: Notational conventions; Special forms; Booleans; Equivalence predicates; Pairs and lists; Symbols; Numbers; Characters; Strings; Vectors; The object table, Sponsored in part by Grant NSF-NCS83-03325.

A feasibility study to determine if Langmuir isotherm analysis could be used to study the attachment of Neisseria gonorrhoeae to human tissue culture cells was completed. Requirements for isotherm analysis (equilibrium, reversibility, sub-saturation conditions) were met. The technique demonstrated that gonococcal colony phenotypes differ in their attachment potential for different eukaryotic cell lines. Factors other than pili appeared to function as attachment mediators; these possible attachment mediators remain of unknown composition. Attachment appeared to be very pH dependent attaching best at slightly alkaline conditions. The role of semen and cervical secretions in the attachment process was investigated. Seminal plasma significantly reduced gonococcal attachment to tissue culture cells. Cervical secretions obtained from control women (no history of gonococcal infection) and test women (recent positive cervical culture) behaved differently in effect on gonococcal attachment. Test secretions significantly promoted the attachment of heavily piliated transparent phenotypes, while control secretions significantly blocked the attachment of heavily piliated opaque phenotypes. Scanning electron microscopy of human uterine cervical and fallopian tube tissue explants demonstrated significantly greater attachment of transparent phenotypes to epithelial surfaces.

In this paper, experimental investigation on the carbosulphidation of alumina for Al production and the sodiothermic reduction of aluminium sulphide are presented. Hydrogen sulphide was used as a reductant and source of sulphur. The experimental investigations of the stage 1 process, Al2O3 carbosulphidation, were carried out at 1 100-1 600 degrees C using a laboratory-scale horizontal-tube resistance furnace. H2S gas, diluted with argon (5% H2S and 95% Ar), was reacted with pellets of a mixture of gamma-Al2O3 and C powders (1:6 molar ratio) to produce Al2S3. The effects of gas injection rate, pelletising pressure, temperature and reaction time on the conversion of Al2O3 to Al2S3 were investigated. The X-ray diffraction results confirmed the formation of Al2S3(s) in the reaction product above 1 400 degrees C. The conversion of Al2O3 to Al2S3 was found to be 99.5% at 160 degrees C for 12 hours. The kinetics analysis of alumina sulphidation using the Ginstling-Brounshtein diffusion model suggested the overall reaction was controlled by the diffusion of H2S gas through the reaction product (liquid Al2S3). The activation energy of the alumina sulphidation reaction was calculated to be 148.5 kJ mol. It has also been demonstrated in this study that Al can be extracted from Al2S3 by sodiothermic reduction using Na or NaH. In the case of Na, a level of Al conversion of 75% has been observed for reaction at 290 degrees C. (Authors)., In this paper, experimental investigation on the carbosulphidation of alumina for Al production and the sodiothermic reduction of aluminium sulphide are presented. Hydrogen sulphide was used as a reductant and source of sulphur. The experimental investigations of the stage 1 process, Al2O3 carbosulphidation, were carried out at 1 100-1 600 degrees C using a laboratory-scale horizontal-tube resistance furnace. H2S gas, diluted with argon (5% H2S and 95% Ar), was reacted with pellets of a mixture of gamma-Al2O3 and C powders (1:6 molar ratio) to produce Al2S3. The effects of gas injection rate, pelletising pressure, temperature and reaction time on the conversion of Al2O3 to Al2S3 were investigated. The X-ray diffraction results confirmed the formation of Al2S3(s) in the reaction product above 1 400 degrees C. The conversion of Al2O3 to Al2S3 was found to be 99.5% at 160 degrees C for 12 hours. The kinetics analysis of alumina sulphidation using the Ginstling-Brounshtein diffusion model suggested the overall reaction was controlled by the diffusion of H2S gas through the reaction product (liquid Al2S3). The activation energy of the alumina sulphidation reaction was calculated to be 148.5 kJ mol. It has also been demonstrated in this study that Al can be extracted from Al2S3 by sodiothermic reduction using Na or NaH. In the case of Na, a level of Al conversion of 75% has been observed for reaction at 290 degrees C. (Authors).

Slurry bubble column (SBC) reactors are a modification of bubble column reactors extensively used in industry for numerous physical and chemical applications. Computational fluid dynamic (CFD) has emerged as a promising tool to understand the multiphase flow phenomena inside the SBC. A computational fluid dynamic model has been developed to incorporate pulp and froth zones into one model. In the present research, froth was considered as a separate phase comprised of a mixture of gas, liquid and solids. Considering the froth phase as a separate phase allowed the incorporation of pulp and froth zones into one model by tracking the formation and destruction of the froth phase due to mass exchange between the pulp and froth. Bubble break-up and coalescence were taken into account in the pulp zone, by employing user functions, written in FORTRAN. The effect of bubble coalescence process due to film rupture was considered in the froth phase. The variation in the concentration of attached particles due to attachment and detachment processes were also taken into account. The CFD model predicted the height of froth layer, the concentration of different bubble sizes in both pulp and froth zones, and finally the multiphase flow phenomena in the slurry column. Froth height was found to increase with the increase of gas flow rate while increasing solid concentration decreased froth height., Slurry bubble column (SBC) reactors are a modification of bubble column reactors extensively used in industry for numerous physical and chemical applications. Computational fluid dynamic (CFD) has emerged as a promising tool to understand the multiphase flow phenomena inside the SBC. A computational fluid dynamic model has been developed to incorporate pulp and froth zones into one model. In the present research, froth was considered as a separate phase comprised of a mixture of gas, liquid and solids. Considering the froth phase as a separate phase allowed the incorporation of pulp and froth zones into one model by tracking the formation and destruction of the froth phase due to mass exchange between the pulp and froth. Bubble break-up and coalescence were taken into account in the pulp zone, by employing user functions, written in FORTRAN. The effect of bubble coalescence process due to film rupture was considered in the froth phase. The variation in the concentration of attached particles due to attachment and detachment processes were also taken into account. The CFD model predicted the height of froth layer, the concentration of different bubble sizes in both pulp and froth zones, and finally the multiphase flow phenomena in the slurry column. Froth height was found to increase with the increase of gas flow rate while increasing solid concentration decreased froth height.

Coarse silica flotation from intermediate pebble product has been carried out in a pilot-plant dual extraction column at an operating phosphate mine in central Florida. The solids feed rate ranged from 4.16 to 5.3 tons/hour and the amine dosages ranged from 0.32 to 0.93 lb/ton. The optimum amine dosage when using recycled process water was determined to be 0.6 lb/ton. With a feed containing 40-45 BPL (% bone phosphate of lime) and 38-45% insolubles, the results show that the intermediate pebble product can be upgraded to 56-61 BPL and an insoluble content of 16-22% at 85-90% BPL recovery.The dual extraction column is shown to be an effective device for upgrading the intermediate pebble product prior to blending with the pebble; advantages of such an upgrade are discussed., Coarse silica flotation from intermediate pebble product has been carried out in a pilot-plant dual extraction column at an operating phosphate mine in central Florida. The solids feed rate ranged from 4.16 to 5.3 tons/hour and the amine dosages ranged from 0.32 to 0.93 lb/ton. The optimum amine dosage when using recycled process water was determined to be 0.6 lb/ton. With a feed containing 40-45 BPL (% bone phosphate of lime) and 38-45% insolubles, the results show that the intermediate pebble product can be upgraded to 56-61 BPL and an insoluble content of 16-22% at 85-90% BPL recovery.The dual extraction column is shown to be an effective device for upgrading the intermediate pebble product prior to blending with the pebble; advantages of such an upgrade are discussed.