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Transition metal Aluminum Boride as a New Candidate for Ambient-Condition Electrochemical Ammonia Synthesis

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Nano-micro Letters 2020年第5期12卷 106-118页

作者： Yang Fu Peter Richardson Kangkang Li Hai Yu Bing Yu Scott Donne erich Kisi Tianyi ma Discipline of Chemistry School of Environmental and Life SciencesUniversity of NewcastleCallaghanNSW 2308Australia School of Engineering University of NewcastleCallaghanNSW 2308Australia CSIRO Energy 10 Murray Dwyer CircuitMayfield WestNSW 2304Australia School of Environmental Science and Engineering Fujian Normal UniversityFuzhou 350007FujianPeople’s Republic of China

Achieving more meaningful N2 conversion by reducing the energy input and carbon footprint is now being investigated through a method of N2 fixation instead of the Haber-Bosch ***,the electrochemical N2 reduction reaction(NRR)method as a rising approach currently still shows low selectivity(Faradaic efficiencymption[applied potential at least-0.2 V versus the reversible hydrogen electrode(RHE)].Here,the role of molybdenum aluminum boride single crystals,belonging to a family of ternary transition metal aluminum borides known as mAB phases,is reported for the electrochemical NRR for the first time,at a low applied potential(-0.05 V versus RHE)under ambient conditions and in alkaline *** to the unique nano-laminated crystal structure of the mAB phase,these inexpensive materials have been found to exhibit excellent electrocatalytic performances(NH3 yield:9.2μg h^-1cm^-2mgcat^-1.,Faradaic efficiency:30.1%)at the low overpotential,and to display a high chemical stability and sustained catalytic *** conjunction,further mechanism studies indicate B and Al as main-group metals show a highly selective affinity to N2 due to the strong interaction between the B 2p/Al 3p band and the N 2p orbitals,while mo exhibits specific catalytic activity toward the subsequent reduction ***,the mAB-phase catalyst under the synergy of the elements within ternary compound can suppress the hydrogen evolution reaction and achieve enhanced NRR *** significance of this work is to provide a promising candidate in the future synthesis of ammonia.

关键词： mAB phase N2 reduction reaction Electrocatalysis Nanostructure

Laser back scatter: Limitation to higher repetition rate [kHz] Satellite Laser Ranging system

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Geodesy and Geodynamics 2021年第1期12卷 48-53页

作者： Farhat Iqbal G.Kirchner F.Koidl erich Leitgeb Department of Physics University of SargodhaPakistan Space Research Institute Head of Department Satellite GeodesyAustrian Academy of SciencesLustbuehelstrasse 46A-8042GrazAustria Space Research Institute Engineer at Department Planetary GeodesyAustrian Academy of Sciences HpLustbuehelstrasse 46A-8042GrazAustria Institut für Hochfrequenztechnik Institute of Microwave and Photonic EngineeringGraz University of TechnologyA-8010GrazInffeldgasse 12Austria

Satellite laser ranging(SLR)with higher repetition rate is the recent trend for its various *** backscatter(coincidence between recently transmitted pulses and received pulses near the detector)is found to be a constraint for the repetition rates higher than 20 kHz,due to,overlapping with photons returning from a satellite with the present constellation of most of the SLR *** an overlap occurs at every 75 km satellite distance change at 2 kHz repetition rate,and remains for about 7.5 km;for a 20 kHz system however,it will occur after every 7.5 km and remains for 7.5 km,resulting in constant backscatter overlap e leaving no chance to avoid *** resulting noise is 5 times more than before causing a serious problem in detection and lowers the signal to noise ratio of the overall SLR ***,decreasing energy per shot at higher repetition rates e assuming a constant power laser e the resulting backscatter may decrease fractionally.

关键词： Satellite laser ranging Higher repetition rate Noise Retro reflectors

Flavonols Protect Arabidopsis Plants against UV-B Deleterious Effects

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molecular Plant 2013年第4期6卷 1376-1379页

作者： Julia Emiliani erich Grotewold maría Lorena Falcone Ferreyra Paula Casat Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI) Universidad Nacional de Rosario Suipacha 531 2000 Rosario Argentina Center for Applied Plant Sciences The Ohio State University Columbus OH 43210 USA Department of molecular Genetics The Ohio State University Columbus OH 43210 USA

Dear Editor, Flavonols are synthesized by flavonol synthase （FLS） enzymes （martens et al., 2010）. These compounds absorb UV-B light in the 280-320-nm region and their concentration increases in plants exposed to environmental abiotic and biotic stresses, including UV-B; consequently, flavonols are thought to act as UV-B filters （Agati et al., 2011）. It has been also suggested that these metabolites function as reactive oxygen species （ROS） scavengers, as they contain an OH- group in the 3-position of the flavonoid skeleton, which allows them to chelate metals, inhibiting the formation of free radicals and ROS accumula- tion, once formed （Agati et al., 2009）. For these reasons, it has been suggested that flavonols play uncharacterized roles in UV responses （Verdan et al., 2011）. Nevertheless, despite the fact that the role of flavonols in UV-B protection has been inferred, the protection conferred by flavonols on the target sites of UV-B-damage has not been directly proven in planta.

关键词： Arabidopsis UV-B Deleterious

The Formation of Anthocyanic Vacuolar Inclusions in Arabidopsis thaliana and Implications for the Sequestration of Anthocyanin Pigments

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molecular Plant 2010年第1期3卷 78-90页

作者： Lucille Pourcel Niloufer G. Irani Yuhua LU Ken Riedl Steve Schwartz erich Grotewold Department of Plant Cellular and molecular Biology and Plant Biotechnology Center Ohio State University Columbus OH 43210 USA Department of Food Science and Technology The Ohio State University Columbus OH 43210 USA Present address: Department of Plant Systems Biology Flanders Institute for Biotechnology and Department of Plant Biotechnology and Genetics GhentUniversity 9052 Ghent Belgium Current address: Department of Chemistry Eastern Illinois University Charleston IL 61920 USA

Anthocyanins are flavonoid pigments that accumulate in the large central vacuole of most plants. Inside the vacuole, anthocyanins can be found uniformly distributed or as part of sub-vacuolar pigment bodies, the Anthocyanic Vacuolar Inclusions （AVIs）. Using Arabidopsis seedlings grown under anthocyanin-inductive conditions as a model to un- derstand how AVIs are formed, we show here that the accumulation of AVIs strongly correlates with the formation of cyanidin 3-glucoside （C3G） and derivatives. Arabidopsis mutants that fail to glycosylate anthocyanidins at the 5-0 position （Sgt mutant） accumulate AVIs in almost every epidermal cell of the cotyledons, as compared to wild-type seedlings, where only a small fraction of the cells show AVIs. A similar phenomenon is observed when seedlings are treated with vanadate. Highlighting a role for autophagy in the formation of the AVIs, we show that various mutants that interfere with the autophagic process （atg mutants） display lower numbers of AVIs, in addition to a reduced accumulation of anthocyanins. Interestingly, vanadate increases the numbers of AVIs in the atg mutants, suggesting that several pathways might participate in AVl formation. Taken together, our results suggest novel mechanisms for the formation of sub-vacuolar compartments capable of accumulating anthocyanin pigments.

关键词： Anthocyanin autophagy cyanidin 3-glucoside vacuolar inclusion vanadate.

Preface for special section on long-term behavior of dams

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水科学与水工程：英文版 2016年第3期9卷 173-174页

作者： Si-hong Liu erich Bauer College of Water Conservancy and Hydropower Engineering Hohai University Institute of Applied mechanics Graz University of Technology

When it comes to the long-term operation of hydropowerplants, the service life of mechanical and electrical equipmentand the reliability of hydraulic engineering structures areboth crucial. The loading history and interaction of theconstruction with ground settlements, earthquake activities andflooding, chemical reactions with water, overtopping, and thestate of weathering and aging of the construction material mayplay an important role in the safe operation of hydraulicstructures such as earth, rockfill, and concrete dams, as wellas novel reinforced soil structures. A critical reduction ofthe safety of dams can be caused by the evolution of internalerosion, cracks in the sealing, earthquake-induced deformations,reduction of the slope stability of earth and rockfilldams triggered by heavy rainwater infiltration, or rapid reductionof the water level in the reservoir.

关键词： hydropowerplants equipmentand

Highly efficient passive Tesla valves for microfluidic applications

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microsystems & Nanoengineering 2022年第5期8卷 125-136页

作者： Sebastian Bohm Hai Binh Phi Ayaka moriyama erich Runge Steffen Strehle Jörg König Christian Cierpka Lars Dittrich Theoretical Physics I Technische Universität IlmenauWeimarer Straße 2598693 IlmenauGermany Research and Development 5microns GmbHMargarethenstraße 698693 IlmenauGermany Institute of micro-and Nanotechnologies Gustav-Kirchhoff-Straße 798693 IlmenauGermany microsystems Engineering Technische Universität IlmenauMax-Planck-Ring 1298693 IlmenauGermany Physics and Astronomy Carleton CollegeOne North CollegeNorthfield 55057 MinnesotaUSA Engineering Thermodynamics Technische Universität IlmenauAm Helmholtzring 198693 IlmenauGermany

A multistage optimization method is developed yielding Tesla valves that are efficient even at low flow rates,characteristic,e.g.,for almost all microfluidic systems,where passive valves have intrinsic advantages over active *** report on optimized structures that show a diodicity of up to 1.8 already at flow rates of 20μl s^(−1) corresponding to a Reynolds number of *** of the design is a topological optimization based on the finite element *** is set-up to yield easy-to-fabricate valve structures with a small footprint that can be directly used in microfluidic *** numerical two-dimensional optimization takes into account the finite height of the channel approximately by means of a so-called shallow-channel *** on the threedimensionally extruded optimized designs,various test structures were fabricated using standard,widely available microsystem manufacturing *** manufacturing process is described in detail since it can be used for the production of similar cost-effective microfluidic *** the experimentally fabricated chips,the efficiency of the different valve designs,i.e.,the diodicity defined as the ratio of the measured pressure drops in backward and forward flow directions,respectively,is measured and compared to theoretical predictions obtained from full 3D calculations of the Tesla *** agreement is *** addition to the direct measurement of the diodicities,the flow profiles in the fabricated test structures are determined using a two-dimensional microscopic particle image velocimetry(μPIV)***,a reasonable good agreement of the measured flow profiles with simulated predictions is observed.

关键词： backward Highly optimization

Spatial pattern of impervious surfaces and their impacts on land surface temperature in Beijing,China

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Journal of Environmental Sciences 2007年第2期19卷 250-256页

作者： XIAO Rong-bo OUYANG Zhi-yun ZHENG Hua LI Wei-feng SCHIENKE erich W WANG Xiao-ke State Key Lab of Urban and Regional Ecology Environmental Sciences Chinese Academy of Sciences Belting 100085 China Department of Science and Technology Studies Rensselaer Polytechnic Institute Troy NY 12180 USA

Land surface temperature （LST）, which is heavily influenced by urban surface structures, is a significant parameter in urban environmental analysis. This study examined the effect impervious surfaces （IS） spatial patterns have on LST in Beijing, China. A classification and regression tree model （CART） was adopted to estimate IS as a continuous variable using Landsat images from two seasons combined with QuickBird. LST was retrieved from the Landsat Thematic mapper （Tm） image to examine the relationships between IS and LST. The results revealed that CART was capable of consistently predicting LST with acceptable accuracy （correlation coefficient of 0.94 and the average error of 8.59%）. Spatial patterns of IS exhibited changing gradients across the various urban-rural transects, with LST values showing a concentric shape that increased as you moved from the outskirts towards the downtown areas. Transect analysis also indicated that the changes in both IS and LST patterns were similar at various resolution levels, which suggests a distinct linear relationship between them. Results of correlation analysis further showed that IS tended to be positively correlated with LST, and that the correlation coefficients increased from 0.807 to 0.925 with increases in IS pixel size. The findings identified in this study provide a theoretical basis for improving urban planning efforts to lessen urban temperatures and thus dampen urban heat island effects.

关键词： urban heat islands urban land cover normalized difference vegetation index (NDVI) climate mitigation regression tree

Rapid generation of recombinant Pseudomonas putida secondary metabolite producers using yTREX

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Synthetic and Systems Biotechnology 2017年第4期2卷 310-319页

作者： Andreas Domrose Robin Weihmann Stephan Thies Karl-erich Jaeger Thomas Drepper Anita Loeschcke Institute of molecular Enzyme Technology Heinrich Heine University DüsseldorfForschungszentrum JülichJülichGermany Bioeconomy Science Center(BioSC) Forschungszentrum JülichJülichGermany Institute of Bio-and Geosciences(IBG-1) Forschungszentrum JülichJülichGermany

microbial secondary metabolites represent a rich source of valuable compounds with a variety of applications in medicine or *** exploitation of this wealth of chemicals requires the functional expression of the respective biosynthetic genes in amenable heterologous *** have previously established the TREX system which facilitates the transfer,integration and expression of biosynthetic gene clusters in various bacterial ***,we describe the yTREX system,a new tool adapted for one-step yeast recombinational cloning of gene *** show that with yTREX,Pseudomonas putida secondary metabolite production strains can rapidly be constructed by random targeting of chromosomal promoters by Tn5 *** of this approach was corroborated by prodigiosin production after yTREX cloning,transfer and expression of the respective biosynthesis genes from Serratia ***,the applicability of the system for effective pathway rerouting by gene cluster adaptation was demonstrated using the violacein biosynthesis gene cluster from Chromobacterium violaceum,producing pathway metabolites violacein,deoxyviolacein,prodeoxyviolacein,and *** producing both prodigiosin and violaceins could be readily identified among clones obtained after random chromosomal integration by their strong ***,the addition of a promoter-less reporter gene enabled facile detection also of phenazine-producing clones after transfer of the respective phenazine-1-carboxylic acid biosynthesis genes from Pseudomonas *** compounds accumulated to substantial titers in the mg *** thus corroborate here the suitability of *** for the biosynthesis of diverse natural products,and demonstrate that the yTREX system effectively enables the rapid generation of secondary metabolite producing bacteria by activation of heterologous gene clusters,applicable for natural compound discovery and combinatorial biosy

关键词： Synthetic biology Yeast recombinational cloning Tn5 transposition Heterologous gene cluster expression Secondary metabolite production Pseudomonas putida

放电等离子烧结和快速热压工艺制备具有低或负热膨胀系数钨酸锆块体(英文)

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硅酸盐学报 2009年第5期37卷 749-754页

作者： NEUBAUER erich GAVRILOVIC Aleksandra ANGERER Paul 奥地利研究中心(ARC) 奥地利塞伯斯多夫A-2444 电化学表面技术中心(CEST) 奥地利维也纳新城A-2700

采用快速热压工艺(放电等离子烧结和感应加热热压),利用ZrW2O5粉料制备了负热膨胀系数(coefficient of thermal expansion,CTE)钨酸锆(ZrW2O8)陶瓷体材料。这两种工艺可在烧结过程中保留负CTE材料钨酸锆所需的结构和相组成。结果表明:... 详细信息

采用快速热压工艺(放电等离子烧结和感应加热热压),利用ZrW2O5粉料制备了负热膨胀系数(coefficient of thermal expansion,CTE)钨酸锆(ZrW2O8)陶瓷体材料。这两种工艺可在烧结过程中保留负CTE材料钨酸锆所需的结构和相组成。结果表明:改变工艺参数,如热压温度和保温时间,可以调节 ZrW2O8陶瓷的CTE从-9 × 10-6/K到+9× 10-6/K变化。首次采用ZrW2O8作为填料与轻金属钛复合制备了零膨胀复合材料。

关键词：钨酸锆体材料负热膨胀材料放电等离子烧结技术感应加热热压工艺金属基复合材料