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A machine learning approach for regional geochemical data:Platinum-group element geochemistry vs geodynamic settings of the North Atlantic Igneous Province

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Geoscience Frontiers 2021年第3期12卷 42-59页

作者： Jordan J.Lindsay Hannah S.R.Hughes Christopher m.Yeomans jens C.Ø.Andersen Iain mcDonald Camborne School of mines University of ExeterPenryn CampusPenrynCornwall TR109FEUnited Kingdom School of Earth and Ocean Sciences Main CollegeCardiff UniversityPark PlaceCardiff CF103ATUnited Kingdom

Whilst traditional approaches to geochemistry provide valuable insights into magmatic processes such as melting and element fractionation,by considering entire regional data sets on an objective basis using machine learning algorithms(mLAs),we can highlight new facets within the broader data structure and significantly enhance previous geochemical *** platinum-group element(PGE)budget of lavas in the North Atlantic Igneous Province(NAIP)has been shown to vary systematically according to age,geographic location and geodynamic *** the large multi-element geochemical data set available for the region,mLAs were employed to explore the magmatic controls on these shifting *** key advantage of using machine learning in analysis is its ability to cluster samples across multi-dimensional(i.e.,multi-element)*** NAIP data set is manipulated using Principal Component Analysis(PCA)and t-Distributed Stochastic Neighbour Embedding(t-SNE)techniques to increase separability in the data alongside clustering using the k-means *** new multi-element classification is compared to the original geographic classification to assess the performance of both *** workflow provides a means for creating an objective high-dimensional investigation on a geochemical data set and particularly enhances the identification of metallogenic anomalies across the *** techniques used highlight three distinct multi-element end-members which successfully capture the variability of the majority of elements included as input *** end-members are seen to fluctuate in prominence throughout the NAIP,which we propose reflects the changing geodynamic environment and melting ***,the variability of Pt and Pd are not reflected in mLA-based clustering trends,suggesting that they vary independently through controls not readily demonstrated by the NAIP major or trace element data structure(i.e.,other proxies for magmatic differe

关键词： Platinum-group elements machine learning Plume Geochemistry metallogenesis mantle

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Parallel arrays of Schottky barrier nanowire field effect transistors： Nanoscopic effects for macroscopic current output

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Nano Research 2013年第6期6卷 381-388页

作者： Sebastian Pregl Walter m. Weber Daijiro Nozaki jens Kunstmann Larysa Baraban Joerg Opitz Thomas mikolajick Gianaurelio Cuniberti Institute for materials Science and max Bergmann Center of Biomaterials TU Dresden Dresden 01062 Germany NamLab GmbH Dresden 01187 Germany Fraunhofer Institute IZFP Dresden Dresden 01109 Germany Institute for Semiconductors and microsystems Technology TU Dresden Dresden 01187 Germany Division of IT Convergence Engineering POSTECH Pohang Korea

我们由对有能力的自底向上的成年的硅 nanowires 的一个平行数组组成的现在的新奇 Schottky 障碍领域效果晶体管交付高当前的产量。nanowires 的轴的 silicidation 被用来创造导致多达 106 的开／关水流比率的定义 Schottky 连接。设备... 详细信息

我们由对有能力的自底向上的成年的硅 nanowires 的一个平行数组组成的现在的新奇 Schottky 障碍领域效果晶体管交付高当前的产量。nanowires 的轴的 silicidation 被用来创造导致多达 106 的开／关水流比率的定义 Schottky 连接。设备概念利用 nanoscale 连接的唯一的运输性质为宏观的应用程序增加设备性能。用平行数组，在 0.5 V 的来源排水管电压的超过 500 A 的在水流上能被完成。当维持单个 nanowire 设备的转移特征时，跨导因此显著地被增加。由把几百 nanowires 合并到平行数组，工作晶体管的收益戏剧性地被增加， deviceto 设备可变性与单个设备相比被减少。这个新 nanowirebased 平台提供足够的当前的输出为器官的轻射出的二极管(LEDs ) 为生物传感器或一个开车阶段作为一个变换器被采用，当制造过程的自底向上的性质意味着它能为新奇可印刷的电子设备提供积木时。

关键词：纳米尺度效应场效应晶体管硅纳米线晶体管阵列肖特基势垒电流输出并行阵列宏观

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Expression of fungal biosynthetic gene clusters in S. cerevisiae for natural product discovery

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Synthetic and Systems Biotechnology 2021年第1期6卷 20-22页

作者： Zihe Liu Zhenquan Lin jens Nielsen College of Life Science and Technology Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical Technology100029BeijingChina Department of Biology and Biological Engineering Chalmers University of TechnologySE41296GothenburgSweden Novo Nordisk Foundation Center for Biosustainability Technical University of DenmarkDK2800LyngbyDenmark BioInnovation Institute Ole Maaløes Vej 3DK2200Copenhagen NDenmark

Fungi are well known for production of antibiotics and other bioactive secondary metabolites,that can be served as pharmaceuticals,therapeutic agents and industrially useful ***,compared with the characterization of prokaryotic biosynthetic gene clusters(BGCs),less attention has been paid to evaluate fungal *** is partially because heterologous expression of eukaryotic gene constructs often requires replacement of original promoters and terminators,as well as removal of intron sequences,and this substantially slow down the workflow in natural product *** is therefore of interest to investigate the possibility and effectiveness of heterologous expression and library screening of intact BGCs without refactoring in industrial friendly microbial cell factories,such as the yeast Saccharomyces ***,we discuss the importance of developing new research directions on library screening of fungal BGCs in yeast without refactoring,followed by outlooking prominent opportunities and challenges for future advancement.

关键词： Natural product discovery Cross-species engineering Spliceosome High-throughput BGC cloning Synthetic biology Yeast

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The Sandfish's Skin:morphology,Chemistry and Reconstruction

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Journal of Bionic Engineering 2007年第1期4卷 1-9页

作者： Werner Baumgartner Friederike Saxe Agnes Weth David Hajas Darwin Sigumonrong jens Emmerlich martin Singheiser Wolfgang Bhme Jochen m. Schneider Department of Cellular Neurobionics RWTH-Aachen Kopernikusstr. 16 52056 Aachen Germany material Chemistry RWTH-Aachen Kopernikusstr. 16 52056 Aachen Germany Institute of Zoology RWTH-Aachen Kopernikusstr. 16 52056 Aachen Germany Zoologisches Forschungsmuseum Alexander Koenig (ZFmK) Adenauerallee 160 53113 Bonn Germany

The sandfish is a lizard having the remarkable ability to move in desert sand in a swimming-like fashion. The most outstanding adaptations to this mode of life are the low friction behaviour and the extensive abrasion resistance of the sandfish skin against sand, outperforming even steel. We investigated the topography, the composition and the mechanical properties of sandfish scales. These consist of glycosylated keratins with high amount of sulphur but no hard inorganic material, such as silicates or lime. Remarkably, atomic force microscopy shows an almost complete absence of attractive forces between the scale surface and a silicon tip, suggesting that this is responsible for the unusual tribological properties. The unusual glycosylation of the keratins was found to be absolutely necessary for the described phenomenon. The scales were dissolved and reconstituted on a polymer surface resulting in properties similar to the original scale. Thus, we provide a pathway towards exploitation of the reconstituted scale material for future engineering applications.

关键词： Sandfish Skink Scincus scincus tribology nanoindentation keratin abrasion

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Do birds in flight respond to(ultra)violet lighting?

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Avian Research 2017年第4期8卷 192-201页

作者： Roel may jens Astrom Oyvind Hamre Espen Lie Dahl Terrestrial Ecology Department Norwegian Institute for Nature Research(NINA)TrondheimNorway Steinoysund SmolaNorway.

Background: Concerns for bird collisions with wind turbines affect the deployment of onshore and offshore windpower *** avoid delays in consenting processes and to streamline the construction and operation phase,functional mitigation measures are required which efficiently reduces bird *** is the primary sensory system in birds,which for a number of species also includes the ultraviolet *** bird species that are known to collide with offshore wind turbines are sensitive in the violet or ultraviolet *** species that are mainly active at lower ambient light levels,lighting may deter birds from the lit ***(ultra)violet lights may in addition not disturb ***,we do not know whether UV-sensitive birds in flight actually respond behaviourally to UV ***: We therefore tested the efficacy of two types of lights within the violet(400 nm) and ultraviolet(365 nm) spectrum to deter birds from the lit *** lights were placed vertically and monitored continuously between dusk and dawn using an avian radar ***: Relative to control nights,bird flight activity(abundance) was 27% lower when the ultraviolet light was *** light resulted in a 12% decrease in overall abundance,and in addition,a vertical displacement was seen,increasing the average flight altitude by 7 *** temporal changes occurred,this effect persisted over the season below 40 m above sea ***: Although the results from this pilot study are promising,we argue there still is a long way to go before a potentially functional design to mitigate collisions that has proven to be effective in situ may be in place.

关键词： Avian radar Displacement Habituation mitigation Seabirds Ultraviolet Wind turbine

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Grazing impact on forage quality and macronutrient content of rangelands in Qilian mountains, NW China

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Journal of mountain Science 2019年第1期16卷 43-53页

作者： Alina BARANOVA jens OLDELAND WANG Shun-li Udo SCHICKHOFF CEN Center for Earth System Research and Sustainability Institute of Geography University of Hamburg Biodiversity Ecology and Evolution of Plants Biocenter Klein Flottbek and Botanical Garden University of Hamburg Academy of Water Resource Conservation Forest of Qilian mountains (AWRCFQm)

An important indicator of the rangeland health, associated with land degradation, is the ability of semi-natural rangelands to provide forage of sufficient quality for livestock production. In Qilian mountains(Gansu Province, NW China) biomass production and forage quality are dependent on the seasonality of precipitation and temperature; most of the precipitation falls during summer season, when sheep, goats and yaks graze mountain rangelands. To sustain the rangelands and to improve the management strategies, the assessment of the forage quality should be implemented. The purpose of this research was to study the response of biomass, forage quality and macronutrient content different levels of grazing intensity in Qilian rangelands. We sampled aboveground biomass in the growing seasons in 2012 and 2013 within spring/autumn or summer grazing regimes in two altitudinal zones below and above 3000 m a.s.l.(montane-subalpine and subalpine-alpine respectively). In order to estimate forage quality, biomass was sampled in 1 m × 1 m plots, assigned to the center of 10 ×10 m sites, fromwhich we collected different indicator parameters of rangeland health. mineral and fiber content of forage biomass was estimated under different levels of grazing intensity with regard to the growing period. It was found that an increase in grazing intensity led to a decrease in dry matter weight. No linearity was observed in the relationship between nutritive value and grazing intensity. The highest fiber content(59.20 %) was found in plots mostly disturbed by grazing. The highest protein(16.30 %) and the lowest fiber(51.30 %) contents were associated with slightly grazing intensity. Concentrations of the mineral elements, such as Zn, P, K and S varied significantly and showed maximum values under low grazing intensity.

关键词： Grazing intensity Nutritive value Forage quality mineral concentrations Alpine,Subalpine pastures

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Catalytic Ring Opening of Perhydroindan-Hydrogenolytic and Cationic Reaction Paths

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催化学报 2012年第1期33卷 70-84页

作者： Giuseppe BELLUSSI Andreas HAAS Sandra RABL Dominic SANTI marco FERRARI Vincenzo CALEmmA jens WEITKAmP Eni S.p.A. R＆M DivisionVia F.Maritano 2620097 San Donato MilaneseItaly Institute of Chemical Technology University of Stuttgart70550 StuttgartGermany

Perhydroindan ( bicyclo [ 4.3.0 ] nonane )在六不同催化剂上在 5 mPa 的一个氢压力下面在一台流动类型仪器被变换，也就是在 bifunctional Pd/Na 上，H贝它沸石在 Ir/Na ， H-Y 和 Pt/Na 上，有 Br 的低集中的 H-Y 沸石? nsted 酸... 详细信息

Perhydroindan ( bicyclo [ 4.3.0 ] nonane )在六不同催化剂上在 5 mPa 的一个氢压力下面在一台流动类型仪器被变换，也就是在 bifunctional Pd/Na 上，H贝它沸石在 Ir/Na ， H-Y 和 Pt/Na 上，有 Br 的低集中的 H-Y 沸石? nsted 酸地点，并且在非酸的支持硅石上在三催化剂上包含三高贵金属。在 bifunctional 沸石 Pd/Na 上， H 贝它， perhydroindan 的骨胳的异构化是一枚 naphthenic 戒指开跟随的主要反应，在 ca 的低收益的开链的 nonanes 的形成。6% ，并且 hydrocracked 产品 C8- 。后者的碳数字分发没有与一枚 naphthenic 戒指显示 C9 先锋的 carbocationic 氢化裂解的 C1， C2， C7，和 C8 是塑造火山的。在 Ir/Na 上，到 C8- 的 H-Y 和 Pt/Na， H-Y (高效的戒指洞催化剂) ，戒指洞和氢化裂解在各自的金属上由 hydrogenolysis 发生了。五成员的戒指开比六成员的戒指开被发现快得多，与文学报告一致。开链的 nonanes (OCN ) 的最大的选择在 Ir/Na， H-Y 和 Pt/Na 上到达了， H-Y 很高， viz。分别地， 49% 和 54% 更好与是的 decalin 以前观察的开链的 decanes 比那些为烃建模。在 Pt/Na 上形成的 OCN， H-Y 更不比在 Ir/Na 上形成的那些被分叉，在两金属上以不同 hydrogenolysis 机制被解释的 H-Y。珍贵辅助机械学的信息在硅石上在三高贵金属上从 perhydroindan hydroconversion 的选择被获得。与 Pd/silica 相对照，红外 / 硅石和磅 / 硅石也给了 OCN 的可估计的选择，还这些选择的最大的价值比在二高效的沸石催化剂上获得的那些低。

关键词： ring opening hydrogenolysis bifunctional catalysis perhydroindan open-chain nonanes noble metals silica zeolites

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Electrochemical probing into the active sites of graphitic-layer encapsulated iron oxygen reduction reaction electrocatalysts

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Science Bulletin 2018年第1期63卷 24-30页

作者： Lijie Zhong jens Oluf jensen Lars Nilausen Cleemann Chao Pan Qingfeng Li Department of Energy Conversion and Storage Technical University of Denmark

The graphitic-layer encapsulated iron-containing nanoparticles(G@Fe) have been proposed as a potential type of active and stable non-precious metal electrocatalysts(NPmCs) for the oxygen reduction reaction(ORR). However, the contribution of the encapsulated components to the ORR activity is still unclear compared with the well-recognized surface coordinated FeN_x/C structure. Using the strong complexing effect of the iron component with anions, cyanide(CN^-) in alkaline and thiocyanate(SCN^-) in acidic media, the metal containing active sites are electrochemically probed. Three representative catalysts are chosen for a comparison including the as-prepared encapsulated G@Fe, commercial Fe/N/C catalyst with iron–nitrogen coordinated surface functionalities and molecular iron phthalocyanine(Fe Pc) containing well-defined structures and compositions. It was found that all samples showed significant shifts of half-wave potentials indicating that surface Fe coordinated sites in all cases. The G@Fe catalyst showed the weakest poisoning effect(the lowest shifts of half-wave potential) compared to the Fe/N/C and Fe Pc catalysts in both electrolytes. These results could be explained that the encapsulated iron components influence the FeN_x/C and/or N_xC surface functionality.

关键词：电气化学含铁地点反应探查催化剂包氧表面功能

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Like or dislike:Response of rodents to the odor of plant secondary metabolites

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Integrative Zoology 2017年第5期12卷 428-436页

作者： Sabine C.HANSEN Caroline STOLTER Christian ImHOLT jens JACOB Julius-Kühn Institute for Plant Protection in Horticulture and Forests Vertebrate ResearchMünsterGermany University Hamburg Biocenter Grindel and Zoological MuseumHamburgGermany

Rodents,including common voles(microtus arvalis)and house mice(mus musculus)cause immense pre-harvest and post-harvest ***,developing methods that mitigate these losses while maintaining their role in ecosystems is a *** plant secondary metabolites(PSm)which significantly reduce food intake of both species under laboratory conditions have been ***,before these can be used in rodent pest management,they must be tested under more natural conditions where other food sources are *** this study,the odors of 4 PSms were evaluated for their repellent effects in experiments conducted in semi-natural *** treated with PSms or untreated soil(experimental control)was placed in an underground box containing food(rolled oats).We quantified the number of visits to each box and could demonstrate that all 4 PSms reduced the number of visits to treatment boxes in both rodent *** common voles the combination of methyl nonyl ketone+black pepper oil was the most repellent *** mice made fewer visits to all PSm boxes;boxes with the anthraquinone were visited ***,house mice consumed less food from boxes containing soil treated with all 4 *** results suggest that PSms are repellent in murid and microtine rodents under semi-field *** addition,the future use of PSm odors for repelling both pest species,especially house mice,seems *** investigations with other PSms,different concentrations as well as alternative application methods are needed to repel common voles from attractive crops.

关键词： enclosure trials odor plant secondary metabolites repellents rodents

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Tribological properties of transition metal di-chalcogenide based lubricant coatings

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Frontiers of materials Science 2012年第2期6卷 116-127页

作者： Jun-Feng YANG Braham PARAKASH jens HARDELL Qian-Feng FANG Department of Applied Physics and mechanical Engineering Lulea University of TechnologySE-97187 LuleaSweden Key Laboratory of materials Physics Institute of Solid State PhysicsChinese Academy of SciencesHefei 230031China

Transition metal di-chalcogenides mX2 （X= S, Se, Te; and m = W, mo, Nb, Ta） are one kind of solid lubricant materials that have been widely used in industry. The lubricant properties of such lubricant coatings are dependent not only on microstructure, orientation, morphology, and composition of the coatings, but also on the substrate, the interface between substrate and lubricant coatings, and the specific application environment. In this review, the effects of parameters on tribological properties of such kind of lubricant coatings were summarized. By comparing advantages and disadvantages of those coatings, the special treatments such as doping, structural modulation and post-treatment were suggested, aiming to improve the tribologicai performance under severe test conditions （e.g. high temperature, oxidizing atmosphere or humid condition）.

关键词： transition metal di-chalcogenide solid lubricant coating tribologicalproperty

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