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Characteristics of Nd：GdVO4 Laser with Different Nd-Doping Concentrations

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Chinese Physics Letters 2006年第8期23卷 2088-2091页

作者：张玲张春雨魏志义张治国 Stephan Strohmaier hans j. Eichle Beij.ng National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of SciencesBeijing 100080 Optical Institute Technical University Berlin Strasse de 17 Juni 135 D-10623 Berlin Germany

We report the properties of a compact diode-pumped continuous-wave Nd：GdV04 laser with a linear cavity and different Nd-doped laser crystals. In a 0.2at.% Nd-doped Nd：GdVO4 laser, 1.54 W output laser power is achieved at 912nm wavelength with a slope efficiency of 24.8% at an absorbed pump power of 9.4W. With 0.3at.% Nd-doping concentration, we can obtain the either single-wavelength emission at 1064nm or 912nm or the dual-wavelength emission at 1064nm and 912nm by controlling the incident pump power. From an incident pump power of 11.6 W, the 1064nm emission between ^4Fa/2 and ^4I11/2 is suppressed completely by the 912nm emission between ^4Fa/2 and ^4I9/2. We obtain 670 mW output of the 912nm single-wavelength laser emission with a slope efficiency of 5.5% by taking an incident pump power of 18.4 W. Using a Nd：GdV04 laser with 0.4at.% Nd-doping concentration, we obtain either the single-wavelength emission at 1064nm or the dual-wavelength emission at both 1064nm and 912nm by increasing the incident pump power. We observe a strong competition process in the dualavelength laser.

关键词： Nd:GdVO4 Laser Different Nd-Doping Concentrations

From Single Droplet to Column Design

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Tsinghua Science and Technology 2006年第2期11卷 212-216页

作者： hans-j.rg Bart Institute of Thermal Process Engineering TU Kaiserslautern D-67653 Kaiserslautern Germany

The technique state to design counter-current extraction columns is based on the performance of pilot plant experiments. The modelling is then either with the equilibrium or dispersion model, whereas in the latter the dispersion coefficient accounts for all hydrodynamic non-idealities. A new approach uses single droplet experiments to obtain the basic laws and functions governing droplet breakage, coalescence, relative velocity, and axial dispersion when using droplet populance balance models （DPBM）. The hydrodynamics simulation results show that the mean Sauter diameter, hold-up, and concentration profiles could be well predicted, which promotes the use of DPBM models for further applications in industrial scale.

关键词： single droplet column design countercurrent extraction droplet populance balance model

Silurian-Devonian and j.rassic Thermal Events in the Ordos Basin, China: Indications from K-Ar Dating on Illites

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Acta Geologica Sinica(English Edition) 1996年第4期70卷 435-446页

作者： hans Ahrendt Klaus Wemmer hans-j.rgen Behr Institute of Geology and Dynamics of Lithosphere University of Gttingen G ttingen GermanyInstitute of Geology and Dynamics of LithosphereUniversity of Gttingen G ttingen GermanyInstitute of Geology and Dynamics of LithosphereUniversity of Gttingen G ttingen Germany

In the Ordos basin, two distinct thermal events of different ages have been identified for the first time by means of K-Ar dating combined with illite crystallinity analysis. For the Late Triassic and Late Permian samples, the K-Ar ages of the j.rassic; the K-Ar ages of the <2 μm fractions (210-308 Ma) are interpreted as mixed ages of detrital material and authigenic illites. The K-Ar ages of both < 0.2μm and < 2μm fractions of a Middle Cambrian sample (368 Ma and 419 Ma) correspond to the ages of the metamorphism and earliest granite intrusion in the northern Caledonian Qinling fold zone (380-420 Ma) and show a thermal event during Silurian-Devonian time.

关键词： illite K-Ar dating illite crystallinity thermal event Ordos basin

DSC analyses of static and dynamic precipitation of an Al–Mg–Si–Cu aluminum alloy

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Progress in Natural Science:Materials International 2015年第2期25卷 153-158页

作者： Manping Liu Zhenj.e Wu Rui Yang j.angtao Wei Yingda Yu P?l C. Skaret hans j. Roven School of Materials Science and Engineering Jiangsu Province Key Laboratory of Materials Tribology Jiangsu University Department of Materials Science and Engineering Norwegian University of Science and Technology (NTNU)

In the present investigation, both static and dynamic precipitations of an Al–Mg–Si–Cu aluminum alloy after solid-solution treatment(SST)were comparatively analyzed using differential scanning calorimetry(DSC). Dynamic aging was performed in the SST alloy through equal channel angular pressing(ECAP) at different temperatures of room temperature, 110, 170, 191 and 300 1C. For comparison, static artificial aging was conducted in the SST alloy at 191 1C with two aging times of 4 and 10 h. The DSC analyses reveal that the dynamic precipitation has occurred in the ECAPed samples, while the activation energies associated with the strengthening precipitates in the dynamic samples are considerably higher than the energies in the SST and static aged samples. The higher activation energies are probably attributed to the smaller grains and higher dislocation density developed after ECAP. The results in the present investigation allow the prediction of the type of the dynamic precipitates to influence the strength of the ultrafine grained alloy during ECAP at various temperatures.

关键词： Differential scanning calorimetry Al–Mg–Si–Cu aluminum alloy Dynamic aging Precipitation behaviors Equal channel angular pressing Severe plastic deformation

Comparison of Leptosphaeria biglobosa-induced and chemically induced systemic resistance to *** in Brassica napus

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Chinese Science Bulletin 2007年第8期52卷 1053-1062页

作者： LIU ShengYi LIU RenHu Akinwunmi O. LATUNDE-DADA hans j. COOLS Simon j. FOSTER HUANG Yongj. Bruce D. L. FITT Rothamsted Research Harpenden Hertfordshire AL5 2JQ UK Key Lab of Genetic Improvement of Oil Crops Chinese Ministry0f Agriculture CAAS Oil Crops Research Institute Wuhan 430062 China Zhej.ang Academy of Agricultural Sciences Hangzhou 310021 China

Brassica napus(***)seedlings pre-treated with ascospores of Leptosphaeria biglobosa or foliar sprays of either acibenzolar-S-methyl(ASM)or menadione sodium bisulphite(MSB)were chal- lenge inoculated with *** ascospores and assessed for phoma leaf spot development and tissue morphology and gene expression responses to *** of increase in phoma leaf spot area 8―21 d after challenge inoculation were significantly greater on water pre-treated plants than on plants pre-treated with ***,ASM or MSB on both pre-treated leaves(local effect)and younger leaves without pre-treatment(systemic effect).Ninety-six h after challenge inoculation,the invasive hyphae of *** were encircled by rings of necrotic mesophyll cells on leaves pre-treated with L. biglobosa,ASM or MSB but not those pre-treated with *** of transcript levels of genes commonly used as markers of the maj.r defence signalling pathways(PDF1.2,PR-1,NPR1,APX, CHB4)0–96 h after *** challenge inoculation showed expression patterns indicating prefer- ential activation of the j.smonate/ethylene pathway and involved induction of NPR1 locally and sys- temically in leaves of plants pre-treated with *** ascospores.

关键词：油菜黑胫病抗性黑胫病弱毒种诱导途径比较化学诱导

Surveillance colonoscopy practice in Lynch syndrome in the Netherlands:A nationwide survey

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World j.urnal of Gastroenterology 2007年第34期13卷 4658-4659页

作者： j.n j.Koornstra hans FA Vasen Department of Gastroenterology and Hepatology University Medical Centre Groningen University of Groningen Groningen The Netherlands The Netherlands Foundation for the Detection of Hereditary Tumors Department of Gastroenterology Leiden University Medical Centre Leiden The Netherlands

Lynch syndrome, or hereditary nonpolyposis colorectal cancer (HNPCC), is the most common genetic disorder predisposing to colorectal cancer. As regular colonoscopic surveillance has been shown to reduce the incidence of colorectal cancer, this strategy is recommended worldwide. Recently, several advances in colonoscopic techniques have improved detection rates of neoplasia in Lynch syndrome. In this nationwide survey, we evaluated current surveillance colonoscopy practices for Lynch syndrome in the Netherlands and the extent to which advanced techniques have been adopted in routine clinical practice.

关键词： Lynch syndrome Hereditary nonpolyposiscolorectal cancer Colonoscopy Surveillance Chromoendoscopy

AtGGM2014, an Arabidopsis gene co-expression network for functional studies

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Science China(Life Sciences) 2015年第3期58卷 276-286页

作者： MA ShiSong BOHNERT hans j.DINESH-KUMAR Savithramma P Department of Plant Biology and the Genome Center College of Biological Sciences University of California Departments of Plant Biology and of Crop Sciences University of Illinois at Urbana-Champaign

Gene co-expression networks provide an important tool for systems biology studies. Using microarray data from the Array Express database, we constructed an Arabidopsis gene co-expression network, termed At GGM2014, based on the graphical Gaussian model, which contains 102,644 co-expression gene pairs among 18,068 genes. The network was grouped into 622 gene co-expression modules. These modules function in diverse house-keeping, cell cycle, development, hormone response, metabolism, and stress response pathways. We developed a tool to facilitate easy visualization of the expression patterns of these modules either in a tissue context or their regulation under different treatment conditions. The results indicate that at least six modules with tissue-specific expression pattern failed to record modular regulation under various stress conditions. This discrepancy could be best explained by the fact that experiments to study plant stress responses focused mainly on leaves and less on roots, and thus failed to recover specific regulation pattern in other tissues. Overall, the modular structures revealed by our network provide extensive information to generate testable hypotheses about diverse plant signaling pathways. At GGM2014 offers a constructive tool for plant systems biology studies.

关键词： Arabidopsis gene co-expression network graphical Gaussian model plant development stress response hormone response

Co-residence in Denmark in 1801

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History Research 2012年第3期2卷 219-232页

作者： hans j. Marker Goteborgs Universitet GOteborg Sweden

The Danish 1801 census is available in a fully coded and standardised digital version. This makes it possible to analyse the living conditions of the Danes in new ways. A very central aspect of living conditions is household and family. The census is divided by these lines and therefore calculations of household size and complexity are straight forward and this clearly gives one side of the picture. A totally different side is co-residence analysis. This is not straight forward, but because of the standardisation it is doable. By this means, you get a picture of the likelihood that a person of a given age group lives together with specific relatives. It gives an insight into a central part of living conditions and it gives a picture of differences between sexes and urbanisations. The paper brings the two ways of description together and shows that each has something to contribute to the picture of the Danes.

关键词： the 19th century census co-residence Denmark household family population

Cr^(4+):YAG被动调Q激光器中受激粒子上转换效应对脉冲的影响研究

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物理学报 2003年第10期52卷 2471-2475页

作者：杨林黄维玲丘军林冯宝华张治国 Volker Gaebler Baining Liu hans j.eichler 华中科技大学激光技术国家重点实验室武汉 430074中国科学院物理研究所物理光学实验室北京 100080 华中科技大学激光技术国家重点实验室武汉 430074 中国科学院物理研究所物理光学实验室北京 100080 Optical Institute Technical University BerlinD-10623 BerlinGermany

分析和报道了受激粒子能量上转换 (ETU)效应对Cr:YAG被动调QNd :YAG Nd :YVO4激光器的输出脉冲影响研究 .结合ETU理论分析和被动调Q速率方程组 ,得到了初始反转粒子密度 ,末态反转粒子密度和光强最大时反转粒子密度的比值变化对激光输... 详细信息

分析和报道了受激粒子能量上转换 (ETU)效应对Cr:YAG被动调QNd :YAG Nd :YVO4激光器的输出脉冲影响研究 .结合ETU理论分析和被动调Q速率方程组 ,得到了初始反转粒子密度 ,末态反转粒子密度和光强最大时反转粒子密度的比值变化对激光输出脉冲宽度和脉冲能量的影响 ,和实验结果相一致 .同时讨论了降低ETU效应的方法。

关键词：被动调Q激光器受激粒子能量上转换效应 Cr^4+:YAG激光器优化设计输出脉冲固体激光器饱和吸收体