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Specific minerals in ash are triggers for ash fusion during combustion. This study analyses, for the first time, the link between individual minerals and the ash fusion of pseudo ash pellets using the Optimised Advanced Ash Fusion Test (OAAFT) and FactSage modelling. The study analysed 20 pseudo ash pellets whose composition spanned a wide range of fuels used in the power generation industry. Varying quantities of the 4 main minerals were used to create the pseudo pellets; CaO (0–40%), Fe2O3 (0–40%), MgO (0–25%), and Silica-Alumina ratio (0.5:1–4:1). The OAAFT produced characteristic ash fusion curves for the pseudo pellets and individual minerals. The study also gained insight into the link between mineral transformations and ash fusion by comparing these profiles to the slag formation predictions in the FactSage modelling. Excellent alignment was obtained between the OAAFT curves and FactSage data. The OAFFT curves can be described as individual fingerprints of the ash fusion behaviour of the sample, which can be broken down into individual components. This data cannot be obtained from the conventional ash fusion test. By combining OAAFT and FactSage data, power generators can replicate slagging and fouling issues and identify the major components which are causing issues. The addition of mineral additives can be tested to analyse how slagging and fouling issues can be tackled for specific fuels. This will be of increasing importance as fuel blending and new complex fuels such as refuse derived fuels enter the market.

This study presents the application of a novel approach, using thermal and optical techniques, to identify the causes of poor burnout performance of Colombian stoker furnaces in the Cauca Valley State. The four coals used in these furnaces were characterized to obtain particle size distribution, particle and tapped density, elemental and proximate composition, mineral composition, and maceral content. Up to 80% incomplete combustion was noted in macro-TGA tests compared to complete combustion in a micro-TGA. Reflectance and intrinsic reactivity measurements were for chars prepared in three different particle sizes (6, 6-19, and 19 mm), three temperatures (700, 900, and 1050 °C), and three residence times (10, 30, and 120 min). Two of the coals produced char samples with reflectance values above 6%, which matched those seen in the stoker, indicating that the furnace temperature was not the cause of poor combustion and that only two of the four coals were likely to be present in the furnace bottom ash. These tests were also able to prove that oxygen diffusion limitation was the root cause of the poor burnout where the carbon inside the furnace bottom ash was shielded from oxygen ingress through the formation of a nonpermeable slag layer. Thus, this study demonstrates the potential of both thermal profiling and optical reflectance as a tool for forensically evaluating the thermal history and operational performance of furnaces.

Wet coal beneficiation in Colombia is prohibitive due to the high cost and scarcity of commonly used dense media. The practical value of this study is that it demonstrates for the first time that a common fertilizer, calcium nitrate, can be used in the beneficiation of low-grade Colombian coals. Three high-ash low-grade Colombian coals (Valle, Cundinamarca, and Antioquia) commonly used in Colombian sugar mill stoker furnaces were tested. Coal mineralogy and prevalence were analyzed before and after washing using mineral liberation analysis. The swelling potential of the coals was assessed using a novel application of thermal mechanical analysis (TMA) and an ash fusion oven (AFO). Calcium nitrate reduced ash levels across all size fractions, even for high-ash coals like Valle (29% to below 7%) to acceptable levels for coke manufacturing or pulverized fuel combustion. The novel use of TMA and AFO to analyze coal swelling demonstrated that swelling varies under constrained and unconstrained conditions and the small sample size allows for rapid testing of coal swelling. This study has demonstrated that the use of common fertilizers can allow beneficiation to become a processing option for low-grade coals in Official Development Assistance countries where conventional dense media is prohibitively expensive.

Mechanosynthesis is a powerful alternative to traditional solvent-based synthesis as it allows for higher yields in shorter reaction times, while minimizing the use of solvents. Although mechanochemical routes are becoming increasingly mainstream in synthetic laboratories, up-scaled examples for main group complexes are still rare. Here, motivated by the practical implementation of mechanosynthesis, we demonstrated the synthesis of salen and salophen complexes. The herein reported synthesis displays low E-factor and process mass intensity compared to conventional solution methods. In addition, analyses evaluating environmental parameters, energy consumption, and production cost have been performed, showing the multiple advantages mechanochemistry has over conventional solution-based synthesis. Agency for Science, Technology and Research (A*STAR) Ministry of Education (MOE) Nanyang Technological University F.G. would like to acknowledge A*STAR AME IRG (A1783c0003 and A2083c0050), MOE AcRF Tier 1 (M4011709), and NTU start-up grant (M4080552) for financial support. F.L and V.S. would like to thank A*STAR for fellowship. O.H.C would like to thanks NTU for NPGS scholarship.

Mechanochemistry is a powerful alternative to traditional solvent-based synthesis as it is environmentally benign, allows for higher yields in shorter reaction times, while minimizing the use of solvents. Although mechanochemical routes are becoming increasingly mainstream in synthetic laboratories, up-scales examples for main group complexes are still rare. Here, motivated by the practical implementation of mechanosynthesis, we demonstrated the synthesis of salen and salophen complexes. The herein reported synthesis displays low E-factor and process mass intensity compared to conventional solution methods. In addition, analyses evaluating environmental parameters, energy consumption and production costs have been performed, showing the multiple advantages mechanochemistry has over convetional solution-based synthesis

This paper presents the first multi-tissue study of diet in post-medieval London using both the stable light isotope analysis of carbon and nitrogen and analysis of microdebris in dental calculus. Dietary intake was explored over short and long timescales. Bulk bone collagen was analysed from humans from the Queen’s Chapel of the Savoy (QCS) (n = 66) and the St Barnabas/St Mary Abbots (SB) (n = 25). Incremental dentine analysis was performed on the second molar of individual QCS1123 to explore childhood dietary intake. Bulk hair samples (n = 4) were sampled from adults from QCS, and dental calculus was analysed from four other individuals using microscopy. In addition, bone collagen from a total of 46 animals from QCS (n = 11) and the additional site of Prescot Street (n = 35) was analysed, providing the first animal dietary baseline for post-medieval London. Overall, isotopic results suggest a largely C3-based terrestrial diet for both populations, with the exception of QCS1123 who exhibited values consistent with the consumption of C4 food sources throughout childhood and adulthood. The differences exhibited in δ15Ncoll across both populations likely reflect variations in diet due to social class and occupation, with individuals from SB likely representing wealthier individuals consuming larger quantities of animal and marine fish protein. Microdebris analysis results were limited but indicate the consumption of domestic cereals. This paper demonstrates the utility of a multidisciplinary approach to investigate diet across long and short timescales to further our understanding of variations in social status and mobility. Electronic supplementary material The online version of this article (10.1007/s12520-019-00910-8) contains supplementary material, which is available to authorized users.

This monograph is a case study of newspaper competition in New Hampshire between the province's official newspaper and an upstart Whig challenger in the period marked by contention over the Stamp Act (1765-1766) and over the tight oligarchical reign of the Wentworth family. The case study is grounded in the civic republican tradition articulated by Bernard Bailyn and Gordon Wood as well as the revisionist scholarship since the 1960s that takes the role of the “little people” seriously. It maintains that the competition between the two newspapers contributed to, and opened up, the public spaces in Portsmouth, New Hampshire, to a wider compass than might have been predicted if one follows the standard Habermasian argument for the develop of a bourgeois public sphere. In part, these more diverse public spheres grew out of a staple of ritualized communication in the form of effigy demonstration reports and stamp master resignation speeches at both the local and intercolonial levels. The paper traces the provenance of these reports to the rough music of the colonists' English ancestors so beautifully articulated by E.P. Thompson. The Whig challenger also championed a rollicking and irreverent, rhetorical epistolary form that involved status reversals and mocked deference in a highly amusing, yet serious, manner.

Of all the groups negatively impacted by the Exxon Valdez oil spill, in many ways Alaska Natives were the most devastated. The oil spill.. shook the ... cultural foundations of Native life. Alaska Native subsistence culture is based on an intimate relationship with the environment. Not only does the environment have sacred qualities for Alaska Natives, but their survival depends on the well-being of the ecosystem and the maintenance of cultural norms of subsistence (Gill and Picou, 1997: 168), While Alaska's seven indigenous cultural groups are culturally distinct, its 85,000 Native residents do share a common reverence for the land and sea. Indeed, they see themselves as an integral part of nature. As the quote suggests, Alaska Natives also share cultural norms of subsistence. Since statehood in 1959, subsistence has been at the heart of a cultural divide with Alaska Natives on one side and non-Natives and the State on the other. This ongoing dispute has drawn in the federal government as the trustee for Native subsistence practices. David Case, the foremost expert on Alaska Native laws, maintains that "Actions and events which interfere with subsistence inevitably cut across the whole cloth of Native culture. Understandably, Natives perceive threats to subsistence as threats to their cultural survival..." (1984: 276). Federal legislation in the 1980s generally defined subsistence as encompassing three conceptual elements: (a) continued economic or physical reliance, (b) cultural or social value, and (c) custom or tradition (Case, 1984: 275). In dealing with subsistence issues, the State of Alaska has vacillated between recognizing Native cultural values and invoking values of individualism and common use. In 1989, the Alaska Supreme Court ruled that the rural subsistence preference discriminated against urban residents. This decision led to a federal takeover of hunting and fishing regulations on federal lands in Alaska (60 percent of the state) in order to protect Native subsistence rights (McBeath and Morehouse, 1994: 113). The subsistence issue and its rural/urban and Native/non-Native split is replicated on most development issues in Alaska, including those on federal lands. Consequently, when the supertanker Exxon Valdez ripped its hull open on Bligh Reef on March 24, 1989, and spilled nearly 11 million gallons of crude oil in the pristine waters of Prince William Sound, it became a potent symbol of these disparate ideological interests. The interests at stake included those of multinational oil companies, of a heavily oil-dependent Alaskan state government, of a federal government with military and energy interests in oil, of an American public in love with gas-guzzling automobiles, of environmentalists from conservationists to preservationists, and of culturally distinct Alaska Native groups. Given the centrality of land in these ideological differences, it is useful to think of the "Far North" as sites or places of sharp conflict between those desiring to extract valuable natural resources, those desiring to protect threatened species and land, and those striving to maintain the vitality and integrity of unique human cultures (see Young, 1992, 5). In their analysis of public opinion and media discourses, Gamson and Modigliani suggest that on any policy issue it is appropriate to think of multiple discourses interacting in complex ways (1989: 2-3). As they see it, journalists manage this complexity by producing internally structured packages with up to five framing devices that make sense of events and suggest what is at issue (1989: 2-3). Their framing devices include metaphors, exemplars from the past, catchphrases, depictions, and visual images (1989: 3). while all of these framing devices are of course pertinent to the journalistic packaging of the Exxon Valdez oil spill, I have dealt with most of them in previous research' and will here largely restrict my analysis to a particular form of visual imagery. …

Beginning with the arrival of Russian fur traders in 1741, Alaska natives have faced repeated threats to their territorial sovereignty and subsistence practices. Their struggles to maintain their cultures have taken place against the backdrop of a white discursive hegemony that has defined the terms of the conflicts as well as the very identity of the people. To reveal a piece of this symbolic terrain, the authors examine the work of Presbyterian missionary Sheldon Jackson and The North Star, a newspaper he established in Sitka in the late nineteenth century. An analysis of Jackson's concepts of indigenous cultures as embodied in his educational and ethnological activities reveals his aim of erasing indigenous cultures to civilize and christianize the natives. A critical reading of The North Star shows how it was used as a publicity device to enlist the support of influential Eastern readers in the mission's work.

(R)-3-Hydroxycarboxylic acids, chiral enantiomers of bacterial polyhydroxyalkanoates (PHA), may be valuable synthons for the production of numerous industrial materials such as β-lactams, fungicides, flavors, pheromones and vitamins. In this study, (R)-3-hydroxycarboxylic acid [(R)-3HAs)] synthons were produced by Streptomyces sp. JM3 (JN166713) under batch fermentation. Initial confirmation of PHA production was achieved by matrix assisted laser desorption ionization-time of flight mass spectroscopy and gas chromatography/mass spectroscopy (GC/MS). Subsequently, (R)-3HAs were produced by in vivo depolymerization and the monomers were separated using acid precipitation and anion exchange chromatography. The (R)-3HAs were identified by GC/MS as 3-trimethylsiloxy esters of decanoic, octanoic and butanoic acids. This was further supported by (13)C nuclear magnetic resonance spectrometry. The (R)-3HAs exhibited antimicrobial activity against Escherichia coli O157:H7, Listeria monocytogenes (ATCC 7644) and Salmonella typhimurium (ATCC 14028) with minimum inhibitory concentration ranging from 12.5 to 25 mg ml(-1). However, the minimum bactericidal concentration data suggest that the (R)-3HAs may be bactericidal for E. coli O157:H7 and bacteriostatic for S. typhimurium and L. monocytogenes. Furthermore, the major purified synthon was shown to minimize the invasion of fibroblasts by S. typhimurium (ATCC 14028) [p0.05], using the MTT assay [(3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide)].

Students of the news will welcome Deepa Kumar’s analysis of coverage of the 1997 UPS strike. Media coverage of that strike was notable for its departure from standard narratives concerning labor-management disputes. Most often, strikes are framed as disruptive, inconvenient to the public, and harmful to the economy.While news reports about the UPS strike often reflected these pro-business sentiments, they also, at times, represented labor’s point of view. Kumar presents a comprehensive examination of why this coverage was anomalous. Kumar adopts a ‘‘domination/resistance’’ model of media power, following Gramsci’s notion of hegemony. Based on this model, she argues that the news media are contradictory institutions that most often uphold the status quo by an over-reliance on official sources, and by unreflectively reproducing a professional ideology congruent with values and beliefs of the country’s power structures. She takes liberal apologists of the news media to task for their easy acceptance of the marriage of capitalism and democracy, criticizes the Chomsky-Herman model of political economy of the media for its overemphasis on the engineering of consent, and skewers postmodernist versions of cultural studies for their valorization of textual reading as resistance. Kumar maintains that, for the last third of the twentieth century, neoliberal strategies of globalization have given rise to a whole series of working class issues that were not unique to UPS: part-time employment, stagnant wages, subcontracting, speedups, diminished safety and health protection, and the pension grab. The heart of her book resides in her textual/framing analyses of network television in chapter 3, and mainstream newspaper coverage by USA Today, the New York

This article charts and analyses the place of community radio among rural-based Native Alaskans. The introduction of community radio received major financial support during the War on Poverty in the 1960s, but since has had to struggle and compromise on principles of control for existence. One of the outcomes of this struggle was increasing cultural self-awareness and willingness to engage in collective actions by Alaska Natives. The analysis of this development leans on Carey’s notion of a ritual view of communication, and the authors contend, in conclusion, that the cultural integrity of Native peoples in Alaska requires restoration of local control over community radio.

Despite Wright's optimistic claim in 1974 that func tionalism was alive and well, it seems that both con ceptually and empirically, functionalism has been o f little value... Mass communication theory needs a comprehensive research approach which takes into consideration producers (including vested interests) and consumers, as well as other definable groups and intervening social processes and relations.... What is needed is a theory of society that embraces not only the control mechanisms serving to maintain the social order but which also deals with the conflict ual processes that resist or attempt to subvert the "equilibrium"....

The researcher who opts for the phenomenological approach must further explore the methods he/she employs in order to identify their ad hoc nature.

Television was introduced to remote areas of Alaska in the 1970s through a series of government sponsored experimental projects in low‐power television transmission, bicycled videocassettes, and satellite delivery. Using a participatory model of development, the state attempted to involve users in planning systems and selecting programs. A review of projects reveals that the power and autonomy of consumer committees were weakened by technical and temporal imperatives.

“Objectivity”; has been a traditional ideal for American journalism despite recent characterizations of the principle as “biased toward the status quo, against independent thinking, and against countenancing questions of morality and responsibility.”; This article explores the role of traditional objectivity in newspaper coverage of the nomination in Alaska of a socialist commissioner of environmental conservation and the subsequent “framing”; of public discussion. The human qualities of sensitivity to history, to civil liberties, and to questions of morality appeared in editorials, but professional norms of objectivity denied reporters the right to exercise their creativity and public responsibility. Reportorial sensitivity to diverse sources is necessary, supplemented by a fundamental and far‐reaching examination of how reportorial language encodes public and private questions in ways that further established positions of power and privilege.

In about 230 BC, Archimedes leaped heedless of convention from his bath and ran, splashing dirty water over everyone, shouting ‘Eureka! Eureka!’ (Greek for ‘Ah! Ah! I've got it!’) through the streets of Syracuse. He did this because he was so delighted at what he'd just found out about the relationship between liquids and immersed objects; at the insight he had had into the principles which were at work. At his DISCOVERY … which he went on to apply. For generating insight, and for producing learning which gets results, there's nothing to compete with finding out for yourself.