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The oxidation of dimethyl ether (DME, 340 ppm in 10% O2) has been studied experimentally in an atmospheric pressure laminar flow reactor in the temperature range from 240 degrees C to 700 degrees C for residence times in the range 2-4 s. The influence of nitric oxide additions up to 620 ppm to the feed gases has also been investigated. Products of reaction were determined by FTIR. In the absence of NO, reaction is first detected at about 260 degrees C. The products in the low-temperature region include formaldehyde (HCHO), and formic acid (HCOOH). The addition of NO leads to the appearance of methyl formate (CH3OCHO). While the overall behaviour of the system can be explained qualitatively in terms of typical low-temperature hydrocarbon ignition, recently published chemical kinetic models for DME ignition do not allow for the formation of these formate species. We find no experimental evidence for the formation of hydroperoxymethyl formate (HPMF, HOOCH2OCHO) which is predicted by the models to be a significant stable intermediate at temperatures below 350 degrees C. Since both formic acid and methyl formate have potentially harmful health effects, these observations may have significant implications for use of DME as a diesel fuel. 相似文献
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Richard P. Haynes 《Journal of Agricultural and Environmental Ethics》2001,14(2):231-240
The quest for a ``theory of nonhuman minds' to assessclaims about the moral status of animals is misguided. Misframedquestions about animal minds facilitate the appropriation ofanimal welfare by the animal user industry. When misframed, thesequestions shift the burden of proof unreasonably to animalwelfare regulators. An illustrative instance of misframing can befound in the US National Research Council's 1998 publication thatreports professional efforts to define the psychologicalwell-being of nonhuman primates, a condition that the US 1985animal welfare act requires users of primates to promote. Thereport claims that ``psychological well-being' is a hypotheticalconstruct whose validity can only be determined by a theory thatdefines its properties and links it to observed data. Thisconception is used to contest common knowledge about animalwelfare by treating psychological well-being as a mentalcondition whose properties are difficult to discover. Thisframework limits regulatory efforts to treat animal subjects lessoppressively and serves the interests of the user industry.A more liberatory framework can be constructed by recognizing thecontested nature of welfare norms, where competing conceptions ofanimal welfare have implications about norm-setting authority, asit does in other regulatory contexts, e.g., food safety. Properlyconceptualized welfare should include both the avoidance ofdistressful circumstances and the relationship between ananimal's capacities to engage in enjoyable activities and itsopportunities to exercise these capacities. This conception ofanimal welfare avoids appropriation by scientific experts.The development of the psychological well-being regulation is agood illustration of how social norms are contested and thenappropriated, and a critique of this appropriation shows how itcan be challenged. 相似文献
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Qian?Sun Kenneth?F.?Haynes Jordan?D.?Hampton Xuguo?ZhouEmail authorView authors OrcID profile 《Die Naturwissenschaften》2017,104(9-10):79
In social insects, the postembryonic development of individuals exhibits strong phenotypic plasticity in response to the environment, thus generating the caste system. Different from eusocial Hymenoptera, in which queens dominate reproduction and inhibit worker fertility, the primary reproductive caste in termites (kings and queens) can be replaced by neotenic reproductives derived from functionally sterile individuals. Feedback regulation of nestmate differentiation into reproductives has been suggested, but the sex specificity remains inconclusive. In the eastern subterranean termite, Reticulitermes flavipes, we tested the hypothesis that neotenic reproductives regulate worker-reproductive transition in a sex-specific manner. With this R. flavipes system, we demonstrate a sex-specific regulatory mechanism with both inhibitory and stimulatory functions. Neotenics inhibit workers of the same sex from differentiating into additional reproductives but stimulate workers of the opposite sex to undergo this transition. Furthermore, this process is not affected by the presence of soldiers. Our results highlight the reproductive plasticity of termites in response to social cues and provide insights into the regulation of reproductive division of labor in a hemimetabolous social insect. 相似文献
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Richard Haynes Frans W. A. Brom Jan Elliott Peter Schaber 《Journal of Agricultural and Environmental Ethics》2000,13(1):1-5
Editorial Introduction
From the Editors 相似文献59.
Mark E. Paddrik Richard Haynes Andrew E. Todd William T. Scherer Peter A. Beling 《The Environmentalist》2016,36(2):167-182
Electronic markets and automated trading have resulted in a drastic increase in the quantity and complexity of regulatory data. Reconstructing the limit order book and analyzing order flow is an emerging challenge for financial regulators. New order types, intra-market behavior, and other exchange functionality further complicate the task of understanding market behavior at multiple levels. Data visualizations have proven to be a fundamental tool for building intuition and enabling exploratory data analysis in many fields. In this paper, we propose the incorporation of visualizations in the workflow of multiple financial regulatory roles, including market surveillance, enforcement and supporting academic research. 相似文献
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The Kings Cross/St. Pancras area has been a rail transport hub from Central London to the Midlands and North Eastern England
since the middle of the nineteenth century and dust from the Kings Cross railway lands was even described by Charles Dickens.1 The Channel Tunnel high speed Rail Link (CTRL) is being constructed between 2001 and 2007 to connect continental Europe to
Central London. The CTRL and associated development will help regenerate an area that is surrounded by deprived high density
housing estates. London Borough of Camden has set up an extensive particulate monitoring programme to determine if there are
any health impacts on local residents from emissions from the demolition and construction work. This article assesses the
results from particulate measurements in 2003–2004 and compares this to baseline conditions before the redevelopment work
began. The evidence suggests that although 2003 had higher than average pollution levels in the UK as a whole, even higher
levels of particulates in the size range PM10–PM2.5 (defined as PMcoarse) were measured in Kings Cross. Due to the size of these particulates, they tend to be released from construction works rather
than transport or secondary particulate sources. Concentrations in 2004 were lower than 2003, but this was primarily due to
meteorological conditions. The paper also looks at the health of the local population and discusses whether these elevated
levels are creating a problem and legally constitute a statutory nuisance. The Council continues to work with the contractors
to try and ensure best practical means to minimise dust emissions and their effect on local residents.
1Our Mutual Friend 相似文献