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Recent Developments in the Chemistry of Woody Odorants

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复旦学报（自然科学版） 2005年第5期44卷 777-778页

作者： andreas Goeke Shanghai Givaudan Ltd Pu Dong Zhangjiang High-Tech Park 298 Li Shi-zhen Road Shanghai 201203 China

Woody odorants constitute an important olfactory family in perfumery[1]. Essential wood oils, traditionally being obtained by steam distillation of plant materials, are extensively being used in a variety of *** oil (e. g. in "Gentlemen", Givenchy), vetiver oil ("Vetiver", J. P. Guerlain) and cedar wood oil ("Déclaration", Cartier) are classics in this field. On the other hand, many terpenic hydrocarbons which are perse not particularly useful as perfume ingredients, have been functionalized in order to obtain more sophisticated scents. Javanol(R), Belambre(R), Ysamber K(R) and Ambrocenide(R) (prepared from pinene, camphor,logifolene and cedrene) are the names of potent and recently commercialized wood odorants. However, due to variable qualities of the natural starting materials, it has been an important task in fragrance research to find inexpensive but fully synthetic alternatives which, in light of the complexity of the structures, remains challenging. See Fig. 1.

关键词：木制香料嗅觉阳离子环化作用氢化物

Organocatalytic Domino-methylenation/Diels-Alder Reactions

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复旦学报（自然科学版） 2007年第5期46卷 600-601页

作者： andreas Goeke Shanghai Givaudan Ltd Pu Dong Zhang Jiang High-Tech Park

1 Results Organocatalytic reactions are currently very much en vogue as the term implies a connotation of ecologically benign *** addition,beautiful new results have been achieved over the last few years which triggered a dramatic increase in publications[1].Related to this topic is the catalysis of organic transformations by hydrogen bond donors and organic Brnsted acids[2].From an industrial point of view,these reactions can be beneficial when performed in water in high concentration,prerequ...

关键词： Diels-Alder organocatalysis methylenation selectivity odor

Educating Learners for Their Future,Not Our Past

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ECNU Review of Education 2018年第1期1卷 58-75页

作者： andreas Schleicher The Organization for Economic Co-operation and Development(OECD)

Purpose-This paper aims to examine the educational demands in the digital age from tomorrow’s teachers and policy-makers,and to encourage and incentivize all actors to develop the innovative learning environments that we need for tomorrow’s ***/Approach/Methods-As a conceptual paper,this article has consulted and analyzed a wide range of updated data and literature to consolidate the argumentation on tomorrow’s educational ***-The paper mainly provides possible answers on how to educate students for their future,rather than our *** heart of future education is to help students develop a reliable compass and tools,transformative competency,and to navigate through an increasingly complex,volatile,and uncertain *** fulfill this core mission,a new set of curriculum design principles,changing school system,renewed teacher culture,and an alternative assessment program are highly ***/Value-Based on the latest observations and reflections,the paper broadens our visions on tomorrow’s education and future schools.

关键词： Transformative competencies learning compass school system professional development

Differential roles of C-3 and C-6 phosphate monoesters in affecting potato starch properties

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Grain & Oil Science and Technology 2024年第2期7卷 79-86页

作者： Li Ding andreas Blennow Yuyue Zhong Department of Plant and Environmental Sciences Faculty of ScienceUniversity of CopenhagenDenmark Department of Sustainable and Bio-inspired Materials Max-Planck Institute of Colloids and InterfacesPotsdamGermany

The effects of starch phosphate monoester content(SPC),namely C-3(C3P)and C-6 phosphate monoesters(C6P),on the starch properties were investigated using four potato starches with varied SPC/C3P/C6P and two nonphosphorylated maize starches with a similar range of amylose content(AC)as *** starch property results showed that a higher SPC is associated with lower turbidity,storage and loss modulus after storage,and water solubility,but higher swelling power(SP)and pasting *** findings suggested that SPC inhibited molecular rearrangement during storage and starch leaching during heating,and enhanced swelling and viscosities due to increased hydration and water uptake caused by the repulsion effect of phosphate groups and a less ordered crystalline *** SPC also resulted in lower resistant starch(RS)content in a native granular state but higher RS after *** correlations further indicated that SPC/C3P/C6P were positively correlated with peak(r^(2)=0.925,0.873 and 0.930,respectively),trough(r^(2)=0.994,0.968 and 0.988,respectively),and final viscosities(r^(2)=0.981,0.968 and 0.971,respectively).Notably,SPC,mainly C3P,exhibited a significantly positive correlation with SP(r^(2)=0.859)and setback viscosity(r^(2)=0.867),whereas SPC,mainly C6P,showed a weak positive correlation with RS after retrogradation(r^(2)=0.746).However,SPC had no significant correlations with water solubility,turbidity and rheology properties,which were more correlated with *** findings are helpful for the food industry to select potato starches with desired properties based on their contents of SPC,C3P,or C6P.

关键词： Starch phosphate monoesters C-3 phosphate monoesters C-6 phosphate monoesters Physicochemical properties In vitro digestibility

Comparison of smoothness-constrained and geostatistically based cross-borehole electrical resistivity tomography for characterization of solute tracer plumes

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Water Science and Engineering 2016年第4期9卷 274-286页

作者： andreas Englert andreas Kemna Jun-feng Zhu Jan Vanderborght Harry Vereecken Tian-Chyi J.Yeh Institute of Geology Mineralogy and GeophysicsRuhr University Bochum Department of Geophysics Steinmann InstituteUniversity of Bonn Kentucky Geological Survey University of Kentucky Agrosphere Institute for Bio- and Geosciences(IBG-3)Forschungszentrum Jlich GmbH Department of Resources Engineering National Cheng Kung University Department of Hydrology and Water Resources The University of Arizona

Experiments using electrical resistivity tomography(ERT) have shown promising results in reducing the uncertainty of solute plume characteristics related to estimates based on the analysis of local point measurements *** explore the similarities and differences between two cross-borehole ERT inversion approaches for characterizing salt tracer plumes,namely the classical smoothness-constrained inversion and a geostatistically based approach,we performed two-dimensional synthetic *** assumptions about the solute transport model and the electrical forward and inverse model allowed us to study the sensitivity of the ERT inversion approaches towards a variety of basic conditions,including the number of boreholes,measurement schemes,contrast between the plume and background electrical conductivity,use of a priori knowledge,and point *** results show that geostatistically based and smoothness-constrained inversions of electrical resistance data yield plume characteristics of similar quality,which can be further improved when point measurements are incorporated and advantageous measurement schemes are *** expected,an increased number of boreholes included in the ERT measurement layout can highly improve the quality of inferred plume characteristics,while in this case the benefits of point conditioning and advantageous measurement schemes *** ERT inversion approaches are similarly sensitive to the noise level of the data and the contrast between the solute plume and background electrical conductivity,and robust with regard to biased input parameters,such as mean concentration,variance,and correlation length of the *** sophisticated inversion schemes have recently become available,in which flow and transport as well as electrical forward models are coupled,these schemes effectively rely on a relatively simple geometrical parameterization of the hydrogeological ***,we believe that standard uncoupled ER

关键词： Electrical resistivity tomography Inversion technique Solute tracer plume Synthetic experiment Plume characteristics

Putting On The Breaks:Regulating Organelle Movements in Plant Cells

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Journal of Integrative Plant Biology 2012年第11期54卷 868-874页

作者： Julianna K.Vick andreas Nebenfhr Department of Biochemistry and Cellular and Molecular Biology University of TennesseeKnoxvilleTN 37996USA

A striking characteristic of plant cells is that their organelles can move rapidly through the cell. This movement, commonly referred to as cytoplasmic streaming, has been observed for over 200 years, but we are only now beginning to decipher the mechanisms responsible for it. The identification of the myosin motor proteins responsible for these movements allows us to probe the regulatory events that coordinate organelle displacement with normal cell physiology. This review will highlight several recent developments that have provided new insight into the regulation of organelle movement, both at the cellular level and at the molecular level.

关键词： Cytoplasmic streaming cytoskeleton myosin organelle.

Assessment of Rill Erosion Development during Erosive Storms at Angereb Watershed, Lake Tana Sub-basin in Ethiopia

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Journal of Mountain Science 2015年第1期12卷 49-59页

作者： Gizaw Desta GESSESSE Reinfried MANSBERGER andreas KLIK Water and Land Resource Centre (WLRC) P.O.Box 3880 Addis Ababa Ethiopia Institute of Surveying Remote Sensing and Land Information (IVFL) University of Natural Resources and Life Sciences Institute of Hydraulics and Rural Water Management (IHLW) University of Natural Resources and Life Sciences

Application of simple and locally based erosion assessment methods that fit to the local condition is necessary to improve the performance and efficiency of soil conservation practices. In this study, rill erosion formation and development was investigated on the topo-sequence of three catchments （300-500 m slope length）; and on agricultural fields （6 m and 24 m slope lengths） with different crop-tillage surfaces during erosive storms. Rill density and rill erosion rates were measured using rill cross section survey and close range digital photogrammetry. Rill formation and development was commonly observed on conditions where there is wider terrace spacing, concave slope shapes and unstable stone terraces on steep slopes. At field plot level, rill development was controlled by the distribution and abrupt change in the soil surface roughness and extent of slope length. At catchment scale, however, rill formation and development was controlled by landscape structures, and concavity and convexity of the slope. Greater rill cross sections and many small local rills were associated to the rougher soil surfaces. For instance, relative comparison of crop tillage practices have showed that faba-bean tillage management was more susceptible to seasonal rill erosion followed by Teff and wheat tillage surfaces under no cover condition. Surface roughness and landscape structures played a net decreasing effect on the parallel rill network development. This implies that spatial and temporal variability of the rill prone areas was strongly associated with the nature and initial size of surface micro-topography or tillage roughness. Thus, it is necessary to account land management practices, detail micro-topographic surfaces and landscape structures for improved prediction of rill prone areas under complex topographic conditions. Application of both direct rill cross section survey and close range digital photogrammetric techniques could enhance field erosion assessment for practic

关键词： Soil erosion Rill erosion survey Digitalphotogrammetry Tillage roughness AngerebWatershed Ethiopia

Extensive reworking of Archaean crust within the Birimian terrane in Ghana as revealed by combined zircon U-Pb and Lu-Hf isotopes

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Geoscience Frontiers 2018年第1期9卷 173-189页

作者： andreas Petersson Anders Scherstén Axel Gerdes Department of Geology Lund UniversitySolvegatan 12SE-223 62 LundSweden Centre for Exploration Targeting School of Earth and EnvironmentUniversity of Western AustraliaCrawleyAustralia Department of Geosciences Swedish Museum of Natural History104 05 StockholmSweden Institut für Geowissenschaften Senckenberganlage 28D-60054 Frankfurt am MainGermany

Located in the southeastern parts of the BaouléMossi domain of the West African Craton,the Birimian terrane in Ghana is known to consist of predominantly juvenile crust emplaced during the Eburnean *** we present novel coupled zircon U-Pb and Lu-Hf isotope data from nine Birimian granitoids intruding different domains from northwestern,western and southeastern ***-chondriticε_(Hf)-values indicating reworking of Archaean crust are recorded in zircon from both northwestern and southeastern *** a conservative estimate 71%of all analysed zircon grains spanning in age from2220 Ma to 2130 Ma require contribution from a reworked Archaean source,contradicting the common belief that the Birimian terrane consist of predominantly juvenile crust.A minimumε_(Hf)-value of-10.5 at2139 Ma suggests a Palaeoarchaean to late Mseoarchaean component as the contributing ancient *** with previously reported heavy zirconδ^(18)O signatures from Birimian river zircon in Ghana,our new data suggests reworking of Archaean aged sediments during subduction initiated crustal growth in the vicinity of one,or possibly in between two Archaean aged cratons.

关键词： Birimian Baoulé Mossi Archaean Crustal growth Zircon

A DIFFUSION–TRANSPORT HYBRID METHOD FOR ACCELERATING OPTICAL TOMOGRAPHY

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Journal of Innovative Optical Health Sciences 2010年第4期3卷 293-305页

作者： HYUN KEOL KIM andreas H.HIELSCHER Department of Biomedical Engineering Columbia University New YorkNY 10027USA Department of Radiology Columbia University New YorkNY 10032USA Department of Electrical Engineering Columbia University New YorkNY 10027USA

It is well acknowledged that the equation of radiative transfer(ERT)provides an accurate prediction of light propagation in biological tissues,while the diffusion approximation(DA)is of limited accuracy for the transport ***,ERT-based reconstruction codes require much longer computation times as compared to DA-based reconstruction *** introduce here a computationally efficient algorithm,called a diffusion–transport hybrid solver,that makes use of the DA-or low-order ERT-based inverse solution as an initial guess for the full ERT-based reconstruction *** evaluate the performance of this hybrid method,we present extensive studies involving numerical tissue phantoms and experimental *** a result,we show that the hybrid method reduces the reconstruction time by a factor of up to 23,depending on the physical character of the problem.

关键词： Optical tomography reconstruction time radiative transfer equation