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晚第四纪青海湖高湖面研究

第四纪研究 2018年第5期38卷 1166-1178页

作者：刘向军赖忠平 david b. madsen 李国强于禄鹏黄昶陈发虎中国科学院青海盐湖研究所中国科学院盐湖资源综合高效利用重点实验室青海西宁810008 中国科学院青海盐湖研究所青海省盐湖地质与环境重点实验室青海西宁810008 中国地质大学(武汉)地球科学学院湖北武汉430074 兰州大学资源环境学院西部环境教育部重点实验室甘肃兰州730000 临沂大学资源与环境学院山东临沂276000 中国科学院青藏高原研究所北京100101

中国西北地区众多封闭湖泊湖岸堤的光释光（OSL）测年结果表明，＂大湖＂存在于深海氧同位素第5阶段（MIS 5）或者更早，而不是MIS 3阶段。由于高湖面测年结果的变化，我们对中国西北以及青藏高原地区湖泊对晚第四纪冰期-间冰期旋回气... 详细信息

中国西北地区众多封闭湖泊湖岸堤的光释光（OSL）测年结果表明，＂大湖＂存在于深海氧同位素第5阶段（MIS 5）或者更早，而不是MIS 3阶段。由于高湖面测年结果的变化，我们对中国西北以及青藏高原地区湖泊对晚第四纪冰期-间冰期旋回气候变化响应的认识也随之改变。本研究对青海湖周边的湖岸堤、湖相沉积物、冲积和风成沉积物进行光释光测年，重建了青海湖末次间冰期以来的高湖面演化历史，得到以下结论：1）最高湖面（拔湖26~66 m）出现在MIS 5时期；2） MIS 3c时期湖面高出现在约13~17 m，但是在MIS 3a阶段湖面下降至接近于中全新世湖面高度；3）全新世最高湖面出现在距今约5.1 ka，湖面至少高出现在9.1 m，之后在约2 ka前再一次出现高湖面，高出现在湖面约8 m。青海湖高湖面的拔湖高度从MIS 5a到MIS 3时期，再到全新世是依次降低的，使得早期的湖岸堤没有被后期高湖面破坏而较好的保存了下来。

关键词：青藏高原青海湖高湖面 OSL测年东亚夏季风

青藏高原边缘地区史前遗址2009年调查试掘报告

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人类学学报 2011年第2期30卷 124-136页

作者：仪明洁高星张晓凌孙永娟中国科学院古脊椎动物与古人类研究所中国科学院人类演化实验室北京100044 中国科学院研究生院北京100039 中国科学院青海盐湖研究所西宁810008

2009年6月—7月,在青藏高原边缘地区调查、试掘了6处遗址,获得一批石制品、动物骨骼残片、火塘等材料。石制品多数个体较小,类型包括石核、石片、工具、断块、细石核、细石叶等。通过对比出土材料及部分遗址测年数据判断,6处遗址的年代... 详细信息

2009年6月—7月,在青藏高原边缘地区调查、试掘了6处遗址,获得一批石制品、动物骨骼残片、火塘等材料。石制品多数个体较小,类型包括石核、石片、工具、断块、细石核、细石叶等。通过对比出土材料及部分遗址测年数据判断,6处遗址的年代处于13ka bP左右的晚更新世至全新世。此次调查试掘,丰富了该区域人类活动的证据,对研究青藏高原环境变化、古人类的适应生存过程及技术交流有一定意义。

关键词：史前遗址青藏高原边缘地区调查试掘

Degradation patterns of silicone-based dielectric elastomers in electrical fields

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International Journal of Smart and Nano Materials 2018年第4期9卷 217-232,I0001页

作者： Liyun Yu Frederikke b.madsen Anne L.Skov Danish Polymer Centre Department of Chemical and Biochemical EngineeringTechnical University of DenmarkKgs.LyngbyDenmark

Silicone elastomers have been heavily investigated as candidates for the flexible insulator material in dielectric elastomer transducers and are as such almost ideal candidates because of their inherent softness and ***,silicone elastomers suffer from low dielectric *** shortcoming has been attempted optimized through different approaches during recent *** optimization with the sole purpose of increasing the dielectric permittivity may lead to the introduction of problematic phenomena such as premature electrical breakdown due to high leakage currents of the thin elastomer *** this work,electrical breakdown phenomena of various types of permittivity-enhanced silicone elastomers are *** showed that different types of polymer backbone chemistries lead to differences in electrical breakdown patterns,which were revealed through SEM *** may pave the way towards a better understanding of electrical breakdown mechanisms of dielectric elastomers and potentially lead to materials with increased electrical breakdown strengths.

关键词： Silicone elastomers dielectric electrical breakdown voltage stabilization characterization

Antimicrobial silicone skin adhesives facilitated by controlled octenidine release from glycerol compartments

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International Journal of Smart and Nano Materials 2023年第3期14卷 369-389页

作者： V.Chiaula J.Jeppe madsen F.b.madsen P.Mazurek A.C.Nielsen A.L.Skov Danish Polymer Centre Department of Chemical and Biochemical EngineeringTechnical University of DenmarkLyngbyDenmark GRD Technology–Adhesives Coloplast A/SHumlebækDenmark

For improved wound healing,antimicrobial adhesives are one path ***,with the current challenge of bacterial resistance,it is essential to choose the included drug *** is an obvious choice due to its broad antimicrobial efficacy and no reported bacterial *** its pure form,octenidine complexes efficiently with the platinum catalyst in the silicone composition,inhibiting the targeted hydrosilyla-tion reaction and hindering *** obstacle is overcome by screening octenidine with cyclodextrins in homogeneously dispersed glycerol droplets,suppressing Pt inhibition in the silicone *** efficiency is demonstrated using rheol-ogy,which shows that it is possible to incorporate one wt%of octenidine into glycerol–silicone adhesives in the presence of(2-hydroxypropyl)-β-cyclodextrin without affecting the adhe-sives’mechanical *** interaction between octeni-dine and(2-hydroxypropyl)-β-cyclodextrin through an inclusion complex is confirmed by ROESY *** this screening,octenidine is still released efficiently from the glycerol–silicone adhesives upon contact with water,and the resulting antimicrobial action is subsequently *** new technology constitutes a simple and efficient method for preparing wound care adhesives that actively inhibit the growth of four bacteria strains and one fungus.

关键词： Silicone adhesive skin adhesive active adhesive antimicrobial

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卧螺离心机内部流动状态与沉降

过滤与分离 1996年第3期6卷 45-47页

作者： b.madsen 张剑鸣四川江北机械厂

卧螺离心机内部流动状态与沉降（丹）Ｂ．Ｍａｄｓｅｎ＊著四川江北机械厂张剑鸣译四川联合大学孙启才校卧螺离心机（图１）以连续方式将悬浮液分离成固相和液相，其分离过程通过高速旋转离心机转鼓实现。被分离出的固相（沉渣）由螺旋... 详细信息

卧螺离心机内部流动状态与沉降（丹）Ｂ．Ｍａｄｓｅｎ＊著四川江北机械厂张剑鸣译四川联合大学孙启才校卧螺离心机（图１）以连续方式将悬浮液分离成固相和液相，其分离过程通过高速旋转离心机转鼓实现。被分离出的固相（沉渣）由螺旋输送器输送到排渣口，螺旋输送器转速...

关键词：离心机卧螺离心机内部流动状态沉降

A mid-Holocene drought interval as evidenced by lake desiccation in the Alashan Plateau, Inner Mongolia, China

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Science bulletin 2003年第14期48卷 1401-1410页

作者： J.A.Holmes D.b.madsen C.G.Oviatt USA University College-London Desert Research Institute Department of Geography Environmental Change Research Center WC1H 0AP KS 66506 USA Correspondence should be addressed to Chen Fahu Department of Geology Reno Kansas State University London NV 89512 Division of Earth and Ecosystem Sciences Manhattan UK

The mid-Holocene in China is traditionally thought to be a warm and humid period with a strong summer monsoon, and is often termed the Holocene Climatic Optimum or Megathermal Period. Here we present lake geomorphologic and lithological evidence from the Alashan Plateau, part of the Mongolian Plateau, that indicates strong lake desiccation during the mid-Holocene. High resolution pollen data from Zhuyeze Lake, at the present summer monsoon margin, is also presented. These data show that present lakes and wetlands in the Juyanze Lake basin west of the badain Jaran desert, in the Zhuyeze Lake basin between the badain Jaran and Tengger deserts, and in lakes in the eastern Tengger desert, dried or experienced low lake levels in the mid-Holocene around 5000—7000 cal yr bP. Pollen data further indicate that the vegetation cover declined in both the local areas and in the Qilian Mountains, suggesting the climate was drier than that associated with the present Asian summer monsoon. This mid-Holocene drought interval was present throughout a quite large region of the south Inner Mongolian Plateau. The period was also probably colder, at least in the high Asian plateaus and mountains.

关键词： western Inner Mongolian Plateau mid-Holocene lake desiccation dry climate.

Computational Methods for Electromechanical Fields in Self-Assembled Quantum Dots

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Communications in Computational Physics 2012年第3期11卷 797-830页

作者： D.barettin S.madsen b.Lassen M.Willatzen Alsion 2 Mads Clausen InstituteUniversity of Southern DenmarkDK-6400 SønderborgDenmark

A detailed comparison of continuum and valence force field strain calculations in quantum-dot structures is presented with particular emphasis to boundary conditions,their implementation in the finite-elementmethod,and associated implications for electronic *** first part of this work provides the equation framework for the elastic continuum model including piezoelectric effects in crystal structures as well as detailing the Keating model equations used in the atomistic valence force field *** the variety of possible structure shapes,a choice of pyramidal,spherical and cubic-dot shapes is made having in mind their pronounced shape differences and practical *** this part boundary conditions are also considered;in particular the relevance of imposing different types of boundary conditions is highlighted and *** the final part,quantum dots with inhomogeneous indium concentration profiles are studied in order to highlight the importance of taking into account the exact In concentration profile for real quantum *** influence of strain,electric-field distributions,and material inhomogeneity of spherical quantum dots on electronic wavefunctions is briefly discussed.

关键词： Quantum dots electromechanical fields continuum model valence force field boundary conditions

Dependence of Specific Impulse of Metal-free Formulations on CHNO-oxidizer′s Element Content and Enthalpy of Formation

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火炸药学报 2015年第4期38卷 1-4页

作者： david b.LEMPERT Institute of Problems of Chemical Physics of Russian Academy of Sciences Semenov av.1ChernogolovkaMoscow Region 142432 Russia

It is shown that it is not correct to estimate energetic characteristics of different compounds of solid composite propellants by evaluation of the specific impulse values of these components serving as an only component in the *** an approach may turn the researcher to a wrong *** has to compare compound′s potential in formulations close to real,*** least with necessary amount of *** of specific impulse upon element content of highenthalpy CHNO oxidizer,its enthalpy of formation,and kind of binder have been found.

关键词： solid composite propellants high-enthalpy oxidizer energetic parameters estimation specific impulse

The great catastrophe: causes of the Permo-Triassic marine mass extinction

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National Science Review 2024年第1期11卷 37-50页

作者： Paul b.Wignall david P.G.bond School of Earth & Environment University of Leeds School of Environmental Sciences University of Hull

The marine losses during the Permo-Triassic mass extinction were the worst ever experienced. All groups were badly affected, especially amongst the benthos(e.g. brachiopods, corals, bryozoans, foraminifers,ostracods). Planktonic populations underwent a fundamental change with eukaryotic algae being replaced by nitrogen-fixing bacteria, green-sulphur bacteria, sulphate-reducing bacteria and prasinophytes. Detailed studies of boundary sections, especially those in South China, have resolved the crisis to a ～55 kyr interval straddling the Permo-Triassic boundary. Many of the losses occur at the beginning and end of this interval painting a picture of a two-phase extinction. Improved knowledge of the extinction has been supported by numerous geochemical studies that allow diverse proposed extinction mechanisms to be studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections globally, although the intensity and timing shows regional variability. Decreased ocean ventilation coincides with rapidly rising temperatures and many extinction scenarios attribute the losses to both anoxia and high *** kill mechanisms include ocean acidification for which there is conflicting support from geochemical proxies and, even less likely, siltation(burial under a massive influx of terrigenous sediment) which lacks substantive sedimentological evidence. The ultimate driver of the catastrophic changes at the end of the Permian was likely Siberian Trap eruptions and their associated carbon dioxide emissions with consequences such as warming, ocean stagnation and acidification. Volcanic winter episodes stemming from Siberian volcanism have also been linked to the crisis, but the short-term nature of these episodes(boreal latitudes

关键词： ocean anoxia ocean acidification siltation productivity collapse volcanic winter