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The role of organic electron donors in the initiation of BHAS base-induced coupling reactions between haloarenes and arenes

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Science China Chemistry 2019年第11期62卷 1425-1438页

作者： Andrew j.smith Darren L.Poole john A.Murphy Department of Pure and Applied Chemistry University of StrathclydeStrathclydeGlasgow G11XLUnited Kingdom Flexible Discovery Unit GlaxoSmithKline Medicines Research CentreStevenageSG12NYUnited Kingdom

Coupling reactions between haloarenes and arenes(including heteroarenes)that are conducted without added transition metals but in the presence of KOtBu or NaOtBu,have been a topic of great interest since their discovery in *** organic structures act as additives that assist these *** additives are converted into organic electron donors by the butoxide base and this leads to initiation of the coupling reactions,which proceed by radical chain *** review provides an overview of the initiation stages of these reactions.

关键词： organic electron donor potassium tert-butoxide electron transfer base-promoted homolytic aromatic substitution(BHAS) coupling benzyne

Taxonomic and metabolic shifts in the Coorong bacterial metagenome driven by salinity and external inputs

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journal of Oceanology and Limnology 2018年第6期36卷 2033-2049页

作者： Kelly NEWTON Thomas C.jEFFrIES renee j.smith justin r.SEYMOUr Laurent SEUrONT james G.MITCHELL School of Biological Sciences Flinders University School of Science and Health Western Sydney University Flinders Centre for Innovation in Cancer Flinders University Climate Change Cluster University of Technology Sydney Centre National de la recherche Scientifi que Laboratoire d'Océanologie et de Géosciences

The Coorong estuary lies at the terminus of Australia's largest river system, the Murray-Darling; both are strongly influenced by human activities; including farming and extensive flow modification. Metagenomic approaches were used to determine the planktonic bacterial community composition and potential metabolic function at two extremes in the Coorong, the river mouth which exhibits marine-like salinity, and the hypersaline upper-reaches of the estuary. Significant shifts in taxa and metabolic function were seen between the two sites. The river mouth exhibited an increase in abundance of r hodobacteriaceae and Alteromonadaceae; families readily able to adapt to change in nutrient conditions; and the potentially pathogenic families B rucellaceae, Enterobacteriaceae and Vibrionaceae. Metabolisms over-represented include motility and chemotaxis, rNA metabolism and membrane transport, all of which are involved in actively searching for and obtaining nutrients. Also over-represented were metabolisms involved in population succession and stress response. An over-representation of taxa and metabolisms indicative of environmental change is reflective of anthropogenically af fected riverine input. In the hypersaline upper reaches of the estuary, the halophilic family Ectothiorhodospiraceae was over-represented, as were the families Flavobacteriaceae, Cytophagaceae and Nocardioidaceae, members of which are able to survive over a wide salinity range. Metabolisms over-represented here were reflective of increased bacterial growth, characteristic of hypersaline environments, and included DNA metabolism, nucleotide and nucleoside synthesis and cell cycle. Coorong metagenomes clustered taxonomically and metabolically with other planktonic metagenomes, but remained an outlier of this group with only 71% and 84% similarity, respectively. This indicates that the Coorong exhibits a unique planktonic bacterial community that is influenced by riverine input at the river mouth and sali

关键词： hypersaline estuary bacteria taxonomy metabolic potential

Quantum photonics: feature introduction

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Photonics research 2019年第12期7卷 I0001-I0002页

作者： XIAN-MIN jIN M.S.KIM BrIAN j.smith School of Physics and Astronomy and State Key Laboratory of Advanced Optical Communication Systems and Networks Shanghai Jiao Tong UniversityShanghai 200240China QOLS Blackett LaboratoryImperial College LondonLondon SW72AZUK Department of Physics and Oregon Center for Optical Molecularand Quantum ScienceUniversity of OregonEugeneOregon 97403USA

Photons,the individual quanta of the light field,are what the science of quantum photonics is dedicatedly *** manipulation and coherent control of photons in quantum photonics enables the exploration of various quantum phenomena of high fundamental *** the meantime,due to the fast speed and a lack of the interaction with the environment,photons are now regarded as a promising platform for the emerging quantum information processing(QIP)***,there is a growing number of works on quantum computing,quantum communication,and quantum metrology that are solidly based on the techniques of quantum photonics.

关键词： quantum coherent enable

Porous solid inspired hyper-crosslinked polymer liquids with highly efficient regeneration for gas purification

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Science China Materials 2022年第7期65卷 1937-1942页

作者： Stefan j.D.smith Colin D.Wood Paul H.M.Feron Hamidreza Mahdavi roger j.Mulder Cara M.Doherty Matthew r.Hill Xavier Mulet CSIrO Manufacturing Private Bag 10Clayton SouthVIC 3169Australia Department of Chemical Engineering Monash UniversityClaytonVIC 3800Australia Australian resources research Centre KensingtonWA 6155Australia CSIrO Energy P.O.Box 330NewcastleNSW 2300Australia

Separation media that combine the desired material properties within a single material for a given process remain an ongoing challenge for the gas separations in *** integration of porous solid adsorbents is difficult due to their limited volumetric capacity,whereas issues of volatility and high regeneration temperatures exist for liquid amines and physical ***,we report a family of polymer liquids inspired by hyper-crosslinked polymers(HCPs),a class of highly swellable network *** with a chemically similar porous solid,the HCP-liquids demonstrate good volumetric capacity and improved selectivity of carbon dioxide over *** appears to be enhanced by intramolecular swelling of the HCP-liquids at elevated pressures,while guests are strongly rejected from the HCP-liquids at slightly elevated temperatures,leading to highly efficient *** of adsorption and specific heat capacity of the HCP-liquids are also low,further suggesting favourable process *** being easily prepared at scale,the presented HCP-liquids represent a promising step towards a material with the requisite properties to replace conventional scrubbing solvents to drastically reduce the footprint and energy needs of gas separations.

关键词： hyper-crosslinked polymers swellable network efficient regeneration porous liquids gas sorption

Oxidative Stress During Antituberculous Therapy in Young and Elderly Patients

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Biomedical and Environmental Sciences 1995年第2期8卷 106-113页

作者： A.WALUBO P.j.smith 等 DepartmentofPharmacology UniversityofCapeTownMedicalSchoolObservatory7925SouthAfrica Departmentof

Using allantoin (ATN ) as a marker for reactive oxygen species (rOS), oxidative stress during antituberculous (anti-TB) therapy was compared in 10 young and 9 elderly *** treatment, ATN plasma concentrations in patients were similar to that of volunteers. Administration of a combination of isoniazid (INH ), rifampicin (rIF) and pyrazinamid e (PZA) increased plasma ATN in both groups of patients. ATN concentrations (M± SE) at six hours were higher (P rly than in young patients on day one,8.22 ± 1.50 vs 1.89 ± 0.98 μg/mL); day 30, (5.85 ± 0.82 vs 0.87 ± 0.57 μg/mL; and day 90, (4.84 ± 1.24 vs 0.52 ± 0.50μg/mL). Because total amount of ATN excreted was similar in both groups on the three occasions, more ATN was formed in elderly than young patients. In conclusion, there was more oxidative stress in elderly than young patients. It is thereby suggested that Anti-TB drugs induce formation of rOS and elderly patients are at a greater risk of toxicity probably because of poor antioxidant mechanisms

关键词： TBArS Oxidative Stress During Antituberculous Therapy in Young and Elderly Patients UA

Climatic and Edaphic Controls on Soil pH in Alpine Grasslands on the Tibetan Plateau,China:A Quantitative Analysis

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Pedosphere 2014年第1期24卷 39-44页

作者： jI Cheng-jun YANG Yuan-He HAN Wen-Xuan HE Yan-Fang j.smith P.smith Department of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking University State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences College of resources and Environmental Sciences China Agricultural University Institute of Biological & Environmental Sciences School of Biological SciencesUniversity of Aberdeen

Soil acidity is an important parameter that can regulate ecosystem structure and ***,a quantitative understanding of the relationships between soil pH and environmental factors remains *** this study,relationships of soil pH with both climatic and edaphic factors in alpine grasslands on the Tibetan Plateau,China were quantified using data obtained from a regional soil survey during *** results showed that soil pH decreased along the gradient of both mean annual temperature and ***,soil pH exhibited consistent negative correlations with soil moisture and silt ***,soil organic and inorganic carbon contents played opposite roles in shaping patterns of soil pH:the accumulation of soil organic matter led to higher soil acidity,while the existence of soil inorganic matter was favorable for maintaining higher soil *** variation partitioning analysis indicated that the combination of climatic and edaphic variables explained 74.3%of the variation in soil *** results suggest that soil pH could be predicted from routinely-measured variables,allowing a robust pedotransfer function to be *** pedotransfer function may facilitate land surface models to generate more reliable predictions on ecosystem structure and function around the world.

关键词： climate soil acidity soil inorganic carbon soil organic carbon soil texture

Effect of Pressure on Intermediate Valence States in Cerium Kondo Compounds

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journal of rare Earths 2004年第1期22卷 7-12页

作者： Oomi G Kagayama T smith j L Lacerda A H Kaji S Ohashi M Department of Physics Kyushu University Ropponmatsu Fukuoka 810-8560 Japan Department of Mechanical Engineering and Materials Sciences Kumamoto University Kumamoto 860-8555 Japan Materials Science and Technology Los Alamos National Laboratory Los Alamos NM 87545 USA

Electrical resistance, thermal expansion, lattice constants of the intermediate valence materials, α-Ce and CeBe 13, were measured at high pressure. It is found that the Grüneisen parameters of Kondo temperature T K are 13 and 42 for α-Ce and CeBe 13, respectively, and it decreases with increasing pressure. The magnetoresistance of α-Ce shows H2 dependence and its coefficient increases with pressure below 1 GPa, but becomes nearly constant above 1 GPa. The results indicate that the intermediate valence states are enhanced at high pressure indicating the enhancement of hybridization between the 4f electron and conduction band.

关键词： condensel physics intermediate valence materials cerium rare earths

中国人头发纤维在UVA紫外光老化中的光谱学研究

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光谱学与光谱分析 2016年第6期36卷 1783-1788页

作者：唐颖 Gerald j.smith 北京工商大学北京市植物资源研究开发重点实验室北京100048 School of Chemical and Physical Sciences Victoria University of Wellington

生活中,日光中的紫外辐射是导致头发光老化/光损伤的重要环境因素。长时间光照可使染发和天然发出现包括颜色褪变在内的退行性变化。以中老年人的自然灰发为样本来源,通过分离和人工漂染处理,获得了包括自然发色、漂白和染黑的六种头发... 详细信息

生活中,日光中的紫外辐射是导致头发光老化/光损伤的重要环境因素。长时间光照可使染发和天然发出现包括颜色褪变在内的退行性变化。以中老年人的自然灰发为样本来源,通过分离和人工漂染处理,获得了包括自然发色、漂白和染黑的六种头发类型,经过UVA（320～400nm）紫外光老化,采用漫反射光谱、三维荧光光谱和衰减全反射傅里叶变换红外光谱对头发纤维的老化特征进行无损分析,结合头发中光产生过氧化氢的定量分析,探讨了不同发色和漂染处理对头发耐光性的影响。结果表明,UVA辐照可通过Ⅱ型电子转移机制诱导头发中的光敏基团产生过氧化氢,导致纤维表面蛋白和色素分子的光氧化降解。自然发色与漂染发在光老化中的颜色变化不同：灰发和白发主要发生光黄化,人工染发和漂白发分别发生光褪色和光漂白。高湿度环境能加速头发的光降解。化学漂染处理会使头发中的光致过氧化氢水平升高,使纤维处于较高的氧化压力从而影响头发的光稳定性;而头发中的黑色素分子,包括天然黑色素和染发剂的人工黑色素,可能具有自由基产生与清除双重性。研究结果为建立中国人头发光损伤的光谱学评价方法和进一步研发针对国人发质的染护发产品提供了重要的实验基准数据。

关键词：头发纤维 UVA辐射漫反射光谱三维荧光光谱 ATr-FTIr 过氧化氢

Cardiorespiratory and muscular fitness associations with older adolescent cognitive control

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journal of Sport and Health Science 2021年第1期10卷 82-90,I0001页

作者： Tatsuya T.Shigeta Angus A.Leahy jordan j.smith Narelle Eather David r.Lubans Charles H.Hillman Department of Psychology Northeastern UniversityBostonMA 02115USA Priority research Centre for Physical Activity and Nutrition School of EducationUniversity of NewcastleCallaghanNSW 2308Australia Department of Physical Therapy Movement&Rehabilitation SciencesNortheastern UniversityBostonMA 02131USA

Background:Participation in physical activity supports greater cardiorespiratory fitness(CrF),a correlate of cognitive ***,the relationship between muscular fitness(MF)and cognitive control is less *** present study investigated the differential relationship of CrF and MF with cognitive control in older ***:This cross-sectional study involved students(1517 years old,n=541,43%female)from 20 secondary schools who completed tests of inhibition(modified flanker task),working memory(n-back task),CrF(Progressive Aerobic Cardiovascular Endurance run),and MF(standing long jump and push-up test).Multilevel analyses tested the association between CrF or MF and cognitive outcomes while accounting for the influence of the other fitness variable and relevant demographic ***:CrF predicted response accuracy during incongruent flanker trials,the condition requiring greater *** the working memory task,CrF predicted greater target accuracy and greater d’scores on the 1-back task,requiring lesser amounts of working *** the 2-back task,which requires greater amounts of working memory,CrF also predicted greater target and non-target accuracy and d’***,MF did not predict any cognitive outcomes after adjustment for ***:CrF was selectively related to better performance during task conditions that require greater amounts of inhibition and working *** finding suggests that CrF,but not MF,may benefit cognitive control in older *** selective influence of CrF on older adolescents’cognition highlights the value of aerobic physical activity.

关键词： Adolescence Cognition Physical activity Physical fitness