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One chloro-furoeremophilanoid and two new natural dimers from Ligularia atroviolacea

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Chinese Chemical Letters 2008年第11期19卷 1319-1322页

作者： Jun Zhao Hao Wu Ke Xin Huang Shu Yun Shi Hua Peng Xian Feng Sun Liu Rong Chen Qun Xiong Zheng Qi Jun zhang Xiao Jiang Hao Joachim Stockigt Xiao Kun Li Yu Zhao Jia Qu Department of Traditional Chinese Medicine and Natural Drug Research College of Pharmaceutical Sciences Zhejiang University Hangzhou 310058 China Key Laboratory of Southern Zhejiang TCM R＆D Pharmacy School of Wenzhou Medical College Wenzhou 325035 China School of Chemical Engineering Central South University Changsha 410083 China Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China

Three new compounds, including one chloro-furoeremophilanoid （1）, one eremophiladiolide （2）, a rare dimer of nor- furoeremophilanoid, ligulatrovine A （3）, and a known furoeremophilanolide （4）, were isolated from Ligularia atroviolacea. The structures of compounds 1-4 were elucidated by spectroscopic methods including 1D and 2D NMR experiments as well as X- ray diffraction study.

关键词： Natural scsquilcrpene Eremophiladiolidc Dimcr Chloro-furanocrcmophilanc X-ray Ligularia atroviolacea

Phase Structures of Nascent Polyethylene Powder Studied by Wideline Proton NMR

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Chinese Journal of Chemistry 2007年第6期25卷 863-868页

作者：严小伟王靖岱任晓红阳永荣蒋斌波 VODA, Mihai Adrian BERTMER, Marko STAPF, Siegfried College of Material Science and Chemical Engineering Zhejiang University Hangzhou Zhejiang 310027 China Institute of Technical and Macromolecular Chemistry RWTH Aachen University Worringerweg 1 52074 Aachen Germany

The wideline proton NMR spectra of polyethylene powder samples were analyzed in terms of contributions from three components：（1） a rigid part with immobile chains, （2） a soft region with liquid-like character which produces a Lorentzian contribution to the spectrum, and （3） an intermediate region in which the rotation of methylene groups about C-C bonds is partially hindered. The relative mass fractions as well as chain mobilities varied greatly among samples produced by different polymerization techniques. The NMR crystallinity agreed well with that estimated by WAXD and was much higher than DSC crystallinity, indicating an inclusion of the contribution from a crystalline-amorphous interphase. The crystalline defects in the rigid part could be significantly affected by processing parameters when employing the same type of polymerization technique. The intermediate region in the NMR spectra was analyzed according to the comparison between bimodal high density polyethylene and corresponding linear unimodal one. It was found that the mass fraction of the NMR interphase could be an indication of the percentage of tie molecules between crystalline lamellae and thus may significantly affect the mechanical properties of polymeric material.

关键词： polyethylene powder wideline NMR phase structure

Self-diffusion coefficients of organic solvents in linear and branched high density polyethylene particles measured by PFG NMR

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Chinese Chemical Letters 2008年第1期19卷 110-114页

作者： Xiao Wei Yan Xiao Hong Ren Siegfried Stap Jing Dai Wang Yong Rong Yang Department of Chemical Engineering Zhejiang University Hangzhou 310027 China FG Technische Physik ll/Polymerphysik Fakultat fiir Mathematik und Naturwissenschaften Technische Universitiit Ilmenau Postfach 100565 D-98684 Ilmenau Germany Institut fiir Technische Chemie und Makromolekulare Chemie RWTH Aachen University Worringerweg 1 D-52056 Aachen Germany

Pulsed field gradient nuclear magnetic resonance （PFG NMR） has been performed to study the diffusion of organic solvents into semicrystalline polyethylene particles. Self-diffusion coefficients in different domains of the sample can be extracted through a bi- exponential fit to the echo intensity attenuation, which allows the precise determination of the tortuosity of the polyethylene particles. Further exploration comes from the measurements with branched polyethylene particles and it was found that the diffusion in polymer phase contributed significantly to the slow component of the exponential decay curve. 2007 Jing Dai Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Self-diffusion coefficients Pulsed field gradient NMR Tortuosity Polyethylene particle

Phosphorus status, use and recycling in a Chinese peri-urban region with intensive animal husbandry and cropping systems Results from case study in a Sino-German applied research collaboration project

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Frontiers of Agricultural Science and Engineering 2019年第4期6卷 388-402页

作者： Marco ROELCKE Lisa HEIMANN Yong HOU Jianbin GUO Qiaoyun XUE Wei JIA Anne OSTERMANN Roxana Mendoza HUAITALLA Moritz ENGBERS Clemens OLBRICH Roland W.SCHOLZ Joachim CLEMENS Frank SCHUCHARDT Rolf NIEDER Xuejun LIU Fusuo ZHANG Institute of Geoecology Technische Universitat Braunschweig38106 BraunschweigGermany Institute of Crop Science University of Hohenheim70599 StuttgartGermany College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193China College of Engineering China Agricultural UniversityBeijing 100094China Editorial Committee&Editorial Office of PEDOSPHERE Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China China Agricultural Science and Technology Press Chinese Academy of Agricultural SciencesBeijing 100081China Institute for Crop and Soil Science Julius Kuhn Institute(JKI)-Federal Research Centre for Cultivated Plants38116 BraunschweigGermany Institute of Agricultural Engineering University of Hohenheim70599 Institute of Ethics and Transdisciplinary Sustainability Research Leuphana University of Ltineburg21335 LiineburgGermany Department of Business Administration Economics and LawCarl von Ossietzky University of Oldenburg26129 OldenburgGermany Department for Knowledge and Communication Management Danube University Krems3500 KremsAustria SF-Soepenberg GmbH 46569 HiinxeGermany Institute of Agricultural Technology Johann Heinrich von Thiinen Institute(TI)-Federal Research Institute for Rural AreasForestry and Fisheries38116 BraunschweigGermany

The Sino-German research collaboration project,"Recycling of organic residues from agricultural and municipal origin in China"(2008–2012),comprising different interdisciplinary research groups,and also German small and medium-sized enterprises,aimed at developing integrated strategies and solutions for the recycling of organic residues in *** an intensive crop-livestock agricultural region in the Shunyi District of Beijing,five typical cropping systems were *** research was conducted in the form of analyses of phosphorus(P)in soil,plants,animal feed,animal products,manures,mineral and organic fertilizers and the derivation of the corresponding nutrient balances and P *** mean annual P balance surplus was492 kg·ha–1·yr–1 P for the vegetable production system,significantly higher(P30 mg·kg–1)that can lead to increased risk of P loss was exceeded in all five cropping *** feed additives,the"natural background value"(Chinese Environmental Quality Standard for Soils)of copper and zinc in topsoils was exceeded at several *** for several substances in the veterinary antibiotic classes of sulfonamides,tetracyclines,and fluoroquinolones revealed widespread topsoil *** livestock densities were 10.6 livestock units per ha arable land in *** husbandry is increasingly conducted in large operations,making traditional ways of reuse difficult to *** three management systems for treatment of organic

关键词： cropping systems life cycle assessment North China Plain balances and nutrient flows transdisciplinary approach

Towards an Esox lucius inspired multimodal robotic fish

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Science China(Information Sciences) 2015年第5期58卷 182-194页

作者： WU ZhengXing YU JunZhi SU ZongShuai TAN Min LI ZhenLong State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of Sciences College of Electronic Information and Control Engineering Beijing University of Technology

In this paper, we further explore multimodal locomotion via an updated robotic fish model based on Esox lucius. Besides the improved actuation properties like higher torque servomotors and powerful electronics,the robotic fish has some innovative mechanical design to pursue diverse swimming modes and superior performance. Specifically, we introduced a ±50° yawing head joint that functions as the neck for enhancing turning ability. A pair of pectoral mechanisms with two DOFs per fin is constructed to achieve 3-D swimming and to enrich multiple pectoral motions. At the control level, an improved central pattern generator(CPG) model allowing for free adjustment of the phase relationship among outputs is employed to produce rhythmic signals of multimodal swimming. Extensive experiments were carried out to examine how characteristic parameters in CPGs including amplitude, frequency, and phase lag affect the swimming performance. As a result, the robotic fish successfully performed various locomotion actions such as forward swimming, backward swimming, turning, diving, surfacing, as well as three pectoral motions in the form of pitching, heaving, and *** found that small phase lag between oscillating joints which means large propulsive body wave length and undulation width could lead to a faster swimming in body and/or caudal fin(BCF) locomotion.

关键词： bio-inspired robot robotic fish CPG multimodal swimming motion control

Controllable and switchable capillary adhesion mechanism for bio-adhesive pads: Effect of micro patterns

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Chinese Science Bulletin 2009年第10期54卷 1648-1654页

作者： ZHANG XiangJun LIU Yuan LIU YongHe AHMED S.I.-U. State Key Laboratory of Tribology Tsinghua University Beijing 100084 China Institute of Physics and Center for Micro/Nano Technology Technical University of IImenau PF 100565 Germany

Some insects and animals, such as bugs, grasshoppers and tree frogs, realize their efficient adhesion mechanism to glass surface, wall and ceiling by injecting a wetting liquid thin film into the pad-substrate contact area. Their ability to control adhesion (attaching or detaching from a surface) is in many cases connected to the contact geometry and surface patterns of their attachment pads. This paper focuses on the dependence of the capillary adhesion (wet adhesion) on the micro patterns of the bio-adhesive pads. The objective is to reveal the possible mechanism for a bio-adhesive pad to control capillary force through adjusting its micro-scale surface pattern and topography. A capillary adhesion force model is built up taking account of the combined role of micro-dimple geometry as well as the wetting behavior of the confined liquid thin film. Calculated results of the apparent contact angle on the regularly micro-dimpled surfaces are compared with and in good agreement with the experimental measurements. Simulation of the capillary adhesion force reveals that it is controllable in a large mag- nitude by adjusting a dimensionless surface pattern parameter k defined as a/(a+b), where a is the dia- meter of micro dimple, and (a+b) is the side length of one pattern cell. When adjusting the parameter k more than 0.75, the capillary adhesion force could be switchable from attractive to repulsive. This effect of micro patterns on the interfacial capillary force is proved to be dominant when the pad-substrate clearance decreases to the nano/micrometer scale. These results indicate that a controllable and switchable capillary adhesive mechanism might be utilized by a living insect or animal to realize its stable adhesion and quick releasing movement through adjusting the micro-pattern topography of its bio-adhesive pad.

关键词：毛细管力可能机制粘合剂粘附生物开关可控玻璃表面

DeepFilter: A Deep Learning Based Variant Filter for VarDict

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Tsinghua Science and Technology 2023年第4期28卷 665-672页

作者： Hao Zhang Zekun Yin Yanjie Wei Bertil Schmidt Weiguo Liu School of Software Shandong UniversityJinan 250100China Shenzhen Research Institute of Shandong University Shenzhen 518057China Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen 518055China Institute for Computer Science Johannes Gutenberg UniversityMainz 55128Germany

With the development of sequencing technologies,somatic mutation analysis has become an important component in cancer research and *** is a commonly used somatic variant caller for this *** the heuristic-based VarDict algorithm exhibits high sensitivity and versatility,it may detect higher amounts of false positive variants than callers,limiting its clinical *** address this problem,we propose DeepFilter,a deep-learning based filter for VarDict,which can filter out the false positive variants detected by VarDict *** approach trains two models for insertion-deletion mutations(InDels)and single nucleotide variants(SNVs),*** show that DeepFilter can filter at least 98.5%of false positive variants and retain 93.5%of true positive variants for InDels and SNVs in the commonly used tumor-normal paired *** code and pre-trained models are available at https://***/LeiHaoa/DeepFilter.

关键词： variant filter deep learning somatic variant

Potential use of cucumber (Cucumis sativus L.) endophytic fungi as seed treatment agents against root-knot nematode Meloidogyne incognita

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第3期12卷 219-225页

作者： Xiao-ning YAN Richard A. SIKORA Jing-wu ZHENG Institute of Biotechnology College of Agriculture and Biotechnology Zhejiang University Hangzhou 310029 China Soil-Ecosystem Phytopathology and Nematology Institute for Resource Conservation and Plant Science (INRES) Department of Plant Health University of Bonn Bonn 53115 Germany Institute of Environment and Plant Protection Chinese Academy of Tropical Agricultural Sciences Danzhou 5 7173 7 China

Seed treatment with endophytic fungi has been regarded as an effective method for plant parasitic nematode *** fungi from cucumber seedlings were isolated and screened for their potential to be used as seed treatment agents against Meloidogyne *** the 294 isolates screened,23 significantly reduced galls formed by *** in greenhouse *** 10 most effective isolates were Fusarium(5),Trichoderma(1),Chaetomium(1),Acremonium(1),Paecilomyces(1),and Phyllosticta(1) .Their control efficacies were repeatedly tested and their colonizations as well as in vitro activity against *** were *** reduced the number of galls by 24.0%-58.4%in the first screening and 15.6%-44.3%in the repeated test,*** Ph511 and Chaetomium Ch1001 had high colonizations on both the roots and the aboveground parts of cucumber *** isolates had colonization preference on the roots,their root colonizations ranging from 20.1%to 47.3%of the total root *** Tr882,Paecilomyces Pa972,and Acremonium Ac985 had low colonizations on both the roots and the aboveground *** Ac985,Chaetomium Ch1001,Paecilomyces Pa972,and Phyllosticta Ph511 produced compounds affecting motility of the second stage juveniles of *** on these results,Chae-tomium Ch1001 was considered to have the highest potential as a seed treatment agent for *** biocontrol.

关键词： Cucumber endophytic fungi Meloidogyne incognita Control efficacy Colonization In vitro activity

Late Quaternary palaeoenvironmental changes documented by microfaunas and shell stable isotopes in the southern Pearl River Delta plain,South China

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Journal of Palaeogeography 2013年第4期2卷 344-361页

作者： Liu Chunlian Franz T. Fürsich Wu Jie Dong Yixin Yang Tingting Yin Jian Department of Earth Sciences Sun Yat-Sen University Geozentrum Nordbayern FG Pal oumwelt der Friedrich-Alexander-Universitt Erlangen Guangdong Provincial Key Laboratory of Mineral Resources and Geological Processes

Ahigh resolution study of sediments,microfaunas(ostracods and foraminifers),and stable isotopes of ostracod shells from core PRD05,sampled from the Da’ao plain of the Pearl River Delta,provides new data about palaeoenvironmental changes during the Late *** basal fluvial gravelly sediments of the core,representing the lowest deposits of the Quaternary at the core site,were possibly formed prior to the transgression associated with the last interglacial *** fluvial setting changed into a marginal marine setting during the last interglacial stage,any record of calcareous fossils were destroyed by subsequent dissolution during the last glacial phase,when the upper part of the deltaic sediments experienced subaerial oxidation,indicated by a mottled clay layer in the *** postglacial sealevel rise in the South China Sea began at16,700 cal yr *** the first phase of sea-level rise(from ~16,700 to 10,100 cal yr B.P.),a swamp environment developed at the core *** ~10,100 cal yr B.P.,marine waters intruded onto the Da’ao plain and reached the core site through the Modaomen *** timing was earlier than in other parts of the Pearl River *** then,a semi-enclosed estuarine environment developed and was maintained until ~5560 cal yr *** this transgressive interval,short-term environmental fluctuations can be recognized based on microfauna and shell geochemical *** ~10,100 to 8630 cal yr B.P.,the sea-level rose,which was followed by a fall from ~8630 to 8520 cal yr *** expanded transgression occurred between ~8520 and 7900 cal yr *** time intervals from ~8520 to 8200 cal yr *** from ~8080 to 7900 cal yr *** marked by peak *** ~7900 to 5560 cal yr B.P.,the core site generally showed a reduced marine influence and enhanced freshwater input.A fluvial environment developed from ~5560 to 3100 cal yr B.P.,and was succeeded by an alluvial plain setting.

关键词： Late Quaternary microfauna shell stable isotopes palaeoenvironment Pearl River Delta