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Carbon dioxide capture by solvent absorption using amino acids: A review

Chinese Journal of Chemical Engineering 2018年第11期26卷 2229-2237页

作者： Guoping Hu Kathryn H.Smith Yue wu Kathryn A.Mumford Sandra E.Kentish geoffrey w.Stevens Peter Cook Centre for Carbon Capture and Storage Research (PCC) Particulate Fluids Processing Centre (PFPC)Department of Chemical EngineeringThe University of Melbourne

The emission of large amounts of carbon dioxide is of major concern with regard to increasing the risk of climate change. Carbon capture, utilisation and storage (CCUS) has been proposed as an important pathway for slowing the rate of these emissions. Solvent absorption of CO_2 using amino acid solvents has drawn much attention over the last few years due to advantages including their ionic nature, low evaporation rate, low toxicity, high absorption rate and high biodegradation potential, compared to traditional amine solvents. In this review, recent progress on the absorption kinetics of amino acids is summarised, and the engineering potential of using amino acids as carbon capture solvents is discussed. The reaction orders between amino acids and carbon dioxide are typ- ically between 1 and 2. Glycine exhibits a reaction order of 1, whilst, by comparison, lysine, proline and sarcosine have the largest reaction constants with carbon dioxide which is much larger than that of the benchmark solvent monoethanolamine (MEA). Ionic strength, p H and cations such as sodium and potassium have been shown to be important factors influencing the reactivity of amino acids. Corrosivity and reactivity with impurities such as SOx and NOxare not considered to be significant problems for amino acids solvents. The precipitation of CO_2 loaded amino acid salts is thought to be a good pathway for increasing CO_2loading capacity and cutting desorption energy costs if well-controlled. It is recommended that more detailed research on amino acid degradation and overall process energy costs is conducted. Overall, amino acid solvents are recognised as promising potential solvents for car- bon dioxide capture.

关键词： Amino acids Carbon capture Absorption Solvents

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Defining sustainable limits during and after intensification in a maritime agricultural ecosystem

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Ecosystem Health and Sustainability 2017年第8期3卷 15-31页

作者： geoffrey R.Squire Ecological Sciences James Hutton InstituteDundeeUK

Introduction:Intensification of agricultural ecosystems in the 20th century proceeded by a series of innovations that initially ensured food security,but had negative consequences for the in-field and wider environments.A case study in the north Atlantic zone maritime cropland of the UK identified three phases:(1)reorganization between 1940 and 1960,(2)intensification leading to tripling of grain output(1960-1990),and(3)a leveling of output(1990-2015).Outcomes:Innovations that caused the changes together with their effect on life forms,ecological processes and the evolving social,economic and biophysical conditions are *** to design future sustainable systems are hampered by the absence of a baseline before intensification,by inadequate knowledge of in-field processes,and by uncertainty over"safe ranges"in which processes can operate without causing long-term system *** ranges are examined for three attributes recorded over all three phases,namely grain output,fertilizer input and the wild seedbank *** lower limits for grain and nitrogen were quantified as those that ensure grain *** upper limits were identified as those that were economically acceptable to farming in the face of major external perturbations related to food policy and environmental *** these upper limits,fields can maintain a generalist wild species seedbank that supports a farmland food ***:Some properties of the ecosystem therefore attained stability in phase ***,evidence of degrading soil,increasing pesticide use to maintain yield and collapse of specialist plant functions such as nitrogen fixation and pollination,suggest the system is moving toward a phase of decline.

关键词： Ecosystem services intensification resilience safe limits biodiversity

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what are universities for?

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Chinese Science Bulletin 2011年第23期56卷 2506-2517页

作者： geoffrey BOULTON Colin LUCAS The University of Edinburgh University of Oxford

Governments worldwide rightly regard universities as fundamental to the achievement of many national priorities. But it is the paper’s contention that many misunderstand their true benefit to society. Investments in universities are increasingly based on the belief that the science labs in particular of research-intensive universities can be the source of a continuous stream of people and ideas that will spawn innovative and fast growing companies to form the nexus of the knowledge-based economy. This belief is a source of misconceived policies that offer only ultimate disillusion. It is the totality of the university enterprise that is important, as the only place where that totality of ourselves and our world is brought together, and which makes it the strongest provider of the rational explanation and meaning that societies need. In research, universities create new possibilities; in teaching, they shape new people. Its graduates learn to seek the true meaning of things: to distinguish between the true and the merely seemingly true, to verify for themselves what is stable in that very unstable compound that often passes for knowledge. It is the complex, interacting whole of the university that is the source of the separate economic, social, cultural and utilitarian benefits valued by society. It needs to be understood, valued and managed as a whole. These perceptions are a direct challenge to not only to governments but to university administrators who have been either cowed or seduced into the slipshod thinking that is leading to demands that universities cannot satisfy, whilst obscuring their most important contributions. The challenge to both is to permit autonomy without oppressive accountability, and to give staff and students the freedom to think, speculate and research. These are the very conditions of the personal and collective creativity that are the sources of a university’s deepest benefits to its society.

关键词：研究型大学社会需要经济关系工作人员社会根源不稳定管理员实验室

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A case for mantle plumes

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Chinese Science Bulletin 2005年第15期50卷 1541-1554页

作者： geoffrey F. Davies Research School of Earth Sciences Australian National University Canberra ACT 0200 Australia

The existence of at least several plumes in the Earth’s mantle can be inferred with few assumptions from well-established observations. As well, thermal mantle plumes can be predicted from well-established and quanti-fied fluid dynamics and a plausible assumption about the Earth’s early thermal state. Some additional important ob-servations, especially of flood basalts and rift-related mag-matism, have been shown to be plausibly consistent with the physical theory. Recent claims to have detected plumes using seismic tomography may comprise the most direct evidence for plumes, but plume tails are likely to be difficult to resolve definitively and the claims need to be well tested. Although significant questions remain about its viability, the plume hypothesis thus seems to be well worth continued investiga-tion. Nevertheless there are many non-plate-related mag-matic phenomena whose association with plumes is unclear or unlikely. Compositional buoyancy has recently been shown potentially to substantially complicate the dynamics of plumes, and this may lead to explanations for a wider range of phenomena, including “headless” hotspot tracks, than purely thermal plumes.

关键词：地球覆盖物羽毛流体动力学热量对流火山

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Methane dehydroaromatization–A study on hydrogen use for catalyst reduction, role of molybdenum, the nature of catalyst support and significance of Bronsted acid sites

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Journal of Energy Chemistry 2019年第7期28卷 20-32页

作者： Vaidheeshwar Ramasubramanian Hema Ramsurn geoffrey L.Price Russell School of Chemical Engineering The University of Tulsa

Methane dehydroaromatization was studied over Mo/SiO2 and Mo/HZSM-5 with different Mo loadings(2, 5, 10 wt%) at 973 K and 1023 K in a recirculating batch reactor. H2 pretreatment at 1023 K prior to methane activation has significantly improved the catalyst activity with increase in Mo loading and reduced the induction time on benzene formation in both Mo/SiO2 and Mo/HZSM-5. 10 wt% Mo/HZSM-5 gave a maximum methane conversion of 19% and ~67% benzene selectivity at 1023 K. The XRD analysis of used catalysts revealed that the Mo O3 species were converted to β-Mo2C phase. Studies on Mo/SiO2 catalysts showed that benzene was formed even in the absence of acidic zeolite sites. Reactions of ethylene in the presence of pure silica, HZSM-5 and in a blank reactor revealed that conversion of ethylene to aromatics was similar in case of the blank reactor and silica. Thus, it is believed that molybdenum carbide sites act as active sites only for C–H bond activation of methane and ethylene formation. Even though, ethylene can undergo subsequent oligomerization without any catalytic aid to form benzene at973 K and above addition of acidic zeolites improved the selectivity of benzene.

关键词： Methane dehydroaromatization HZSM-5 Silica Molybdenum loading H2 pretreatment Acidic function

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Residual force enhancement due to active muscle lengthening allows similar reductions in neuromuscular activation during position-and force-control tasks

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Journal of Sport and Health Science 2020年第6期9卷 670-676页

作者： Rhiannon Marion geoffrey A.Power Department of Human Health and Nutritional Sciences College of Biological SciencesUniversity of GuelphGuelphOntarioN1G 2W1Canada

Background:Residual torque enhancement(rTE)is the increase in torque observed during the isometric steady state following active muscle lengthening when compared with a fixed-end isometric contraction at the same muscle length and level of neuromuscular *** the rTE state,owing to an elevated contribution of passive force to total force production,less active force is required,and there is a subsequent reduction in *** vivo studies of rTE reporting an activation reduction are often performed using a dynamometer,where participants contract against a rigid restraint,resisting a torque *** has yet to be investigated during a position task,which involves the displacement of an inertial load with positional ***:A total of 12 participants(6 males,6 females;age=22.8±1.1 years,height=174.7±8.6 cm,mass=82.1±37.7 kg;mean±SD)completed torque-and position-matching tasks at 60%maximum voluntary contraction for a fixed-end isometric contraction and an isometric contraction following active lengthening of the ankle ***:There were no significant differences in activation between torque-and position-matching tasks(p=0.743),with^27%activation reduction following active lengthening for both task types(p<0.001).Conclusion:These results indicate that rTE is a feature of voluntary,position-controlled *** findings support and extend previous findings of isometric torque-control conditions to position-controlled contractions that represent different tasks of daily living.

关键词： Eccentric Electromyography History dependence of force Position tasks Residual force enhancement

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Politeness: Is There an East-west Divide?

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外国语 2005年第6期28卷 3-31页

作者： geoffrey Leech Lancaster University UK

The theory of politeness of Brown and Levinson (1978, 1987) has remained the most seminal and influential starting point for cross-cultural and cross-linguistic contrastive pragmatics. Yet is has also provoked countervailing arguments from Ide (1989, 1993), Matsumoto (1989), Gu (1990), Mao (1994) and others, pointing out a western bias in Brown and Levinson’s theory, particularly in their construal of the concept of ‘face’, in their overemphasis on face-threat and their assumption of individualistic and egalitarian motivations, as opposed to the more group-centred hierarchy-based ethos of Eastern societies. This leads to the question in the title of this article: Is there an East-west divide in politeness? The following argument will be presented. There is an overarching framework for studying linguistic politeness phenomena in communication: a common principle of politeness (Leech, 1983, 2002) and a Grand Strategy of Politeness (GSP), which is evident in common linguistic behaviour patterns in the performance of polite speech acts such as requests, offers, compliments, apologies, thanks, and responses to these. The GSP says simply: In order to be polite, a speaker communicates meanings which (a) place a high value on what relates to the other person (typically the addressee), (MAJOR CONSTRAINT) and (b) place a low value on what relates to the speaker. (MINOR CONSTRAINT). It is clear from many observations that constraint (a) is more powerful than constraint (b). The following hypothesis will be put forward, and supported by very limited evidence: that the GSP provides a very general explanation for communicative politeness phenomena in Eastern languages such as Chinese, Japanese and Korean, as well as in western languages such as English. This is not to deny the importance of quantitative and qualitative differences in the settings of social parameters and linguistic parameters of politeness in such languages. A framework such as the GSP provides the parameters of

关键词：跨文化交际礼貌原则语用学英语

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why frequency can no longer be ignored in ELT？

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外语教学与研究 2011年第1期43卷 3-20页

作者： geoffrey Leech Lancaster University

I begin this paper with a brief survey of how frequency — in particular, frequency of words — had a role in language learning in the days before electronic corpora existed. Then I consider how the "corpus revolution" made frequency information available in a totally unprecedented way from the 1960s onward. Finally I discuss the usefulness of frequency to the language learner and teacher, and some new directions in applied linguistics favourable to frequency.

关键词： frequency corpus language learning

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The role of frequency in ELT: New corpus evidence brings a re-appraisal

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外语教学与研究 2001年第5期33卷 328-339页

作者： geoffrey Leech LancasterUniversity

This paper reconsiders the value of frequency information in ELT, taking into account new evidence provided by corpora of native speakers’ English (e.g. the British National Corpus) and evidence available through new dictionaries and grammars making use of such corpus information. Some examples are given, showing how information about frequency in spoken and written English may cause reappraisal of assumptions common in pedagogical grammar. It is argued that frequency as a principle for the selection and prioritising of language content has been neglected, and the availability of corpus_derived frequency information means that this neglect can now be rectified. However, frequency must be considered alongside other factors that have a bearing on sequencing in ELT materials, such as dispersion, coverage, learnability and communicative need. Also, it is important to bear in mind that findings based on corpora of native_speaker English must be complemented by those based on corpora of learner English, and of the native language of the learners.

关键词：英语教学教学方法词汇知识语法教学内容

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Efficient fixation of CO_(2) into propylene carbonate with [BMIM]Br in a continuous-flow microreaction system

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Green Energy & Environment 2021年第2期6卷 291-297页

作者： Yuxin wu Yuncheng Ding Jianhong Xu Yundong wang Kathryn Mumford geoffrey wStevens weiyang Fei The State Key Laborutory of Chemical Engineering Department of Chemical EngineeringTsinghua UniversityBeijing100084China Department of Chemical Engineering The University of MeIbournePurkwilleVictoria3010Austrulia

Utilization of carbon dioxide(CO_(2)) is of great significance in the development of CO_(2) absorption and the solution of greenhouse gas *** efficient conversion of CO_(2) into cyclic carbonate with green catalysts is essential for the more sustainable expansion of CO_(2) *** batch reactor is limited by low efficiency, high cost and low security. Meanwhile, continuous flow system showcased a myriad of virtues, including shortening the residence time from hours to seconds, and decreasing reaction temperature, and possessing the nature of easy industrial scale-up. In this paper, a continuous-flow microreaction system was developed to synthesis propylene carbonate(PC) from propylene oxide(PO) and CO_(2) using 1-butyl-3-methylimidazolium bromide([BMIM]Br) as catalyst. By observing the flow patterns inside microreaction system, the effects of reaction temperature, molar fraction of catalyst, operating pressure, residence time, molar ratio of CO_(2)/PO as well as recycling performance of catalyst on the overall performances were comprehensively evaluated into details. Under different reaction conditions,the flow patterns were set to vary between slug flow and annular flow. The results showed that the yield of propylene carbonate(PC) can reach99.7% at 140℃ and 3.0 MPa with the residence time of 166 s, while the recycling performance of the designed system greatly conforms the future trend of green chemistry.

关键词： Microreaction system Cyclic carbonate Ionic liquids

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