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Model Studies in Heterogeneous Catalysis

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Model Studies in Heterogeneous Catalysis

2005年纳米和表面科学与技术全国会议

作者： hans-joachim freund Fritz-Haber-Institut der Max-Planck-Gesellschaft Dept.of Chemical Physics Faradayweg 4-6 D-14195 BerlinGermany

Model catalyst systems have been prepared by growth of metal nano-aggregates onthin wellordered oxide films of alumina,silica and *** systems lendthemselves to structural and morphological characterization via scanning probemicroscopies and transmission electron microscopy at the atomic scale and bridge to acertain extent the materials gap between metal single crystal studies and theinvestigation of real catalyst samples.

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原子尺度上的异质催化

物理 2007年第5期36卷 370-376页

作者：路军岭高鸿钧时东霞 Shamil Shaikhutdinov hans-joachim freund 中国科学院物理研究所北京凝聚态物理国家实验室 Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4-614195 Berlin Germany Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4-614195 BerlinGermany

现实中的催化剂是个相当复杂的系统体系,且为粉末状,限制了多种表面科学表征手段的应用.科学家通过建立简化的催化剂模型,充分利用目前多种有力的科技分析手段,如扫描隧道显微镜(STM)、透射电镜(TEM)、光电子能谱(XPS)、傅里叶变换红外... 详细信息

现实中的催化剂是个相当复杂的系统体系,且为粉末状,限制了多种表面科学表征手段的应用.科学家通过建立简化的催化剂模型,充分利用目前多种有力的科技分析手段,如扫描隧道显微镜(STM)、透射电镜(TEM)、光电子能谱(XPS)、傅里叶变换红外吸收谱(FTIR)、电子能量损失谱(EELS)等,直观地在原子尺度上研究催化反应的机理,从而使得人们能够设计出选择性能更高、催化性能更好的催化剂.

关键词：异质催化剂模型扫描隧道显微镜(STM) 光电子能谱(XPS) 傅里叶变换红外吸收谱(FTIR) 纳米颗粒氧化物薄膜

Mo（001）表面CaO薄膜过渡层结构的STM研究

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Mo（001）表面CaO薄膜过渡层结构的STM研究

Complexity science meets Earth system

中国化学会第29届学术年会

作者：邵翔 Niklas Nilius hans-joachim freund 中国科学技术大学化学物理系 Fritz-haber Institute of Max-Planck Society Faradayweg 4-614195 BerlinGermany

生长在金属衬底表面的氧化物薄膜,在其厚度较薄的时候往往具有有别于体相氧化物的表面性质。这一方面是由于金属基底的电子态可以直接投射到表面上,影响表面分子过程;另一方面,也往往由于基底的晶格失配而导致薄膜结构相对于体相结构有... 详细信息

生长在金属衬底表面的氧化物薄膜,在其厚度较薄的时候往往具有有别于体相氧化物的表面性质。这一方面是由于金属基底的电子态可以直接投射到表面上,影响表面分子过程;另一方面,也往往由于基底的晶格失配而导致薄膜结构相对于体相结构有偏离,只是随着膜厚增加而不断趋于体相结构。我们在Mo（001）表面成功的制备了CaO（001）单晶化薄膜[1]。然而体系的晶格失配较大,达到了11%,因此薄膜采取了Stranski-Krostanov模式进行生长,即先在Mo（001）表面形成4-5层具有CaxMo1-xO结构的过渡层[2],随后纯相的CaO才开始以岛状形式生长并弥合成膜。我们特别的研究了其中的过渡层薄膜。为了补偿晶格失配造成的应力,其化学组成随着膜厚发生渐变,相应的电子结构也随之变化。而在不同制备条件下,其结构也会不同。另外,对于分子和金属的吸附,这种过度层也展现出了一定的有趣性质。这些性质可以用来调控负载金属的催化活性。

关键词： CaO 薄膜过渡层调控 STM

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Science Bulletin 2025年第1期70卷 19-24页

作者： Jingfang Fan Jun Meng Xiaosong Chen hans joachim Schellnhuber School of Systems Science/Institute of Nonequilibrium Systems Beijing Normal UniversityBeijing 100875China Potsdam Institute for Climate Impact Research Potsdam 14412Germany School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China International Institute for Applied Systems Analysis Laxenburg 2361Austria

The Earth’s climate system operates across multiple scales,driven by intricate interactions among natural processes and human *** these dynamics is crucial for predicting future climate scenarios(days to decades)and their impacts on global environments and *** interactions span across atmospheric circulation,ocean currents,geological processes,and biological systems,influencing global climate variability and regional weather patterns[1].

关键词： Earth climate weather

Impact of renewable energies on the operation and economicsituation of coal fired power stations： Actual situation of coalfired power stations in Germany

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Frontiers in Energy 2017年第2期11卷 119-125页

作者： hans-joachim KRAUTZ Alexander LISK joachim POSSELT Christian KATZER Department for Power Plant Technology Brandenburg University of Technology Cottbus-Senftenberg 03046 Cottbus Gemany

Due to the fluctuating character of the renewable energy sources the demand of conventional power plants for flexibility is increasing. In the recent years, in Germany there has been a fast rise of production capacity of renewable energies, especially from wind turbines, photovoltaic installations, and biomass plants. The installed nominal power of wind turbines is actually (December 2016) 42 GW and of photovoltaic installations 40 GW. The renewable electric energy production in Germany is about 190 TWh/a, which represents a share of 33% of the yearly demand. The increased need for flexibility affects both the power gradients as well as the minimum load of conventional power plants. Due to this flexibility behaviour, conventional power plants are faced with problems concerning the durability of power plant components, corrosion, more maintenance effort and consequently the overall life expectancy. Another consequence of the increasing share of renewable energies is the decreasing full load operating hours, especially of coal fired and gas power plants. Along with decreasing revenues from the energy exchange market, coal fired power plants are faced with new economically challenges.

关键词： flexible load operation minimal load power gradients power plant maintenance corrosion life expectancy

Metamorphic Evolution of Chloritoid-Bearing Micaschist from the Variscan Elstergebirge: Evidences for Stacking of High-Pressure Rocks in the Saxothuringian Zone of Central Europe

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Journal of Earth Science 2020年第3期31卷 425-446页

作者： Gelareh Rahimi hans-joachim Massonne Fakultat Chemie Universitat Stuttgart70569 StuttgartGermany School of Earth Sciences China University of GeosciencesWuhan 430074China

A chloritoid-garnet-bearing micaschist from the southern part of the Elstergebirge was studied to better understand the Variscan orogenic evolution in the Saxothuringian zone of the northwestern Bohemian *** on the textural relations and compositions of minerals,especially of zoned garnet and potassic white mica,a P-T path was reconstructed using contoured P-T *** U-Th-Pb dating of monazite in the micaschist was undertaken with the electron *** micaschist experienced P-T conditions along a clockwise path between 16 kbar at 510℃and 5 kbar at 555℃followed by isobaric heating to about 600℃.Monazite ages range between 315 and 480 Ma with the most prominent maxima and side maxima at 346.0±1.1(2σ),357.3±2.3,and 368.3±1.7 *** older than 380 Ma were related to detrital monazite pointing to a Devonian sedimentary *** ages around 325 Ma were assigned to the isobaric heating by nearby post-tectonic *** high-pressure event,being the result of the collision of Laurussia and Gondwana after closure of the Rheic Ocean,occurred in the Late *** exhumation to 15-20 km(5 kbar)ended probably in the Early *** high-pressure micaschists from the Fichtelgebirge to the Erzgebirge crystalline complexes are suggested to represent a single nappe within a metamorphic nappe *** nappe is composed of metasedimentary slices,which experienced different peak pressures rather than representing a coherent crustal section.

关键词： Saxothuringian micaschist chloritoid garnet monazite dating Variscan P-T path

A Mixed—Mode BIST Scheme Based on Folding Compression

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Journal of Computer Science & Technology 2002年第2期17卷 203-212页

作者：梁华国 Sybille Hellebrand hans-joachim Wunderlich Department of Computer and Information Hefei University of Technology Hefei 230009. P.R. China Institute of Applied Computer Science University of Innsbruck Austria Institute of Computer Science University of Stuttgart Germany

In this paper a new scheme for mixed mode scan-based BIST is presented with complete fault coverage, and some new concepts of folding set and computing are *** scheme applies single feedback polynomial of LFSR for generating pseudo-random patterns, as well as for compressing and extending seeds of folding sets and an LFSR, where we encode seed of folding set as an initial seed of LFSR. Moreover these new techniques are 100%compatible with scan design. Experimental results show that the proposed scheme outperforms previously published approaches based on the reseeding of LFSRs.

关键词： BIST random pattern testing LFSR folding set encoding seed

Pressure-Temperature Evolution of a Mylonitic Gneiss from the Lower Seve Nappe in the Handol Area,Central Sweden

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Journal of Earth Science 2021年第6期32卷 1496-1511页

作者： Botao Li hans-joachim Massonne Xiaoping Yuan School of Earth Sciences China University of GeosciencesWuhan430074China Fakultät Chemie Universität Stuttgart70569StuttgartGermany

Ultrahigh-pressure metamorphism has recently been reported from various crustal rocks in the Seve Nappe Complex(SNC)in which microdiamonds were ***,in gneiss from the Lower Seve Nappe(LSN),neither any direct petrographic indication for UHP was reported nor the metamorphic evolution was well *** studied a mylonitic gneiss from the Handol area of the LSN and applied phase-diagram modeling and Ti-in-biotite *** on the compositions of garnet and biotite and observed mineral assemblages,a path was reconstructed passing through about 8 kbar and 730℃at prograde ***-pressure and initial retrograde stages occurred at 9.0–10.2 kbar at 745-775℃,and 7–9 kbar at<750℃,*** ultrahigh-pressure evidence was recognized compatible with medium-pressure metamorphism deduced in earlier studies of gneiss from the *** higher peak pressures were reported recently for metamorphic rocks of the LSN,a possible interpretation is that slices or erased blocks were subducted,metamorphosed at different depths,and exhumed in a subduction ***,the dominant gneiss of the SNC experienced only a medium-pressure metamorphism in the upper part of the downgoing Baltica *** from different depth levels were brought together in an exhumation channel located between Baltica and the overlying plate.

关键词： Lower Seve Nappe Swedish Caledonides mylonitic gneiss P-T pseudosection modeling Ti-in-biotite thermometry metamorphic rocks

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Effect of HTS Superconductors on Homogeneity of Measurement Field in Low Field Nuclear Magnetic Resonance Detection

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Chinese Physics Letters 2010年第8期27卷 250-252页

作者：董慧张懿 KRAUSE hans-joachim 谢晓明 State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 Institute of Bio- and Nanosystems Forschungszentrum Jiilich. D-52425 Jiilieh Germany Graduate University of the Chinese Academy of Sciences Beijing 100049

In recent years, superconducting quantum interference devices （SQUIDs） have been demonstrated to be useful in the low field nuclear magnetic resonance （NMR） measurements. The high temperature superconducting （HTS） SQUID used in our experiments has a frequency-independent sensitivity of 40-50fT/Hz^1/2. When a liquid nitrogen cooled LC circuit is employed to form a tuned circuit with the SQUID, the sensitivity of the system can be further enhanced. The LC circuit consists of a capacitor and a coil made of copper wire or HTS tape, which is inductively coupled to the SQUID. However, the homogeneity of the measurement field deteriorates because of the HTS tape coil in the proximity of the sample. In contrast, the thin film SQUID with a washer area of 1 cm^2 has no effect on the NMR signal. Therefore, the impairment of the measurement field homogeneity in the case of different superconducting elements nearby is discussed by examining the free induction decay signals at 9 kHz. It is found that a square superconducting film with an area of i cm^2 may compensate for the inhomogeneity of the measurement field after the adjustment of its position.

关键词： Fields Measurement Uses Squids Films Homogenization Packaging materials Tapes