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中国化学会·第十三届全国物理有机化学学术会议

作者：成贵娟 Nikolaos Drosos Bill Morandi walter thiel Max-Planck-Institut für Kohlenforschung Kaiser-Wilhelm-Platz 1 香港中文大学(深圳)

通过生物质转化合成平台化合物由于其可持续性获得广泛的关注,其中多元醇是生物质转化得到的一种常见原料化学品。由于多个羟基的存在,多元醇的选择性脱氧还原反应一直是研究的难点。对于1,2-邻二醇,传统过渡金属催化方法通常还原所有...

通过生物质转化合成平台化合物由于其可持续性获得广泛的关注,其中多元醇是生物质转化得到的一种常见原料化学品。由于多个羟基的存在,多元醇的选择性脱氧还原反应一直是研究的难点。对于1,2-邻二醇,传统过渡金属催化方法通常还原所有羟基或者2-位羟基。这里我们采用量子化学计算研究了首例B(CF)催化1,2-邻二醇的选择性1-位羟基脱氧还原反应。

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四苯乙烯衍生物的激发态失活途径

四苯乙烯衍生物的激发态失活途径

Proterozoic tectonothermal processes imaged with magnetotellurics and seismic reflection in southern Australia

第十三届全国量子化学会议

作者：高远君常雪萍刘向洋李全松崔刚龙 walter thiel 教育部理论计算光化学重点实验室北京师范大学化学学院北京理工大学化学化工学院马克思-普朗克煤炭研究所

聚集诱导发光(AIE)现象的发现为有机发光材料领域打开了一扇新的大门。其中,四苯乙烯(TPE)是常见的构建AIE化合物的基元。取代基位置的改变,TPE化合物的光物理性质也会随之变化,如四(间-甲基)苯乙烯(TPE-4mM)的荧光量子产率(Фf)为0.1%... 详细信息

聚集诱导发光(AIE)现象的发现为有机发光材料领域打开了一扇新的大门。其中,四苯乙烯(TPE)是常见的构建AIE化合物的基元。取代基位置的改变,TPE化合物的光物理性质也会随之变化,如四(间-甲基)苯乙烯(TPE-4mM)的荧光量子产率(Фf)为0.1%,而四(对-甲基)苯乙烯(TPE-4oM)的Фf为64.3%,荧光量子产率比前者提高了600多倍!为了揭示这一现象产生的原因,我们采用静态电子结构计算,并结合非绝热动力学模拟研究了两种TPE衍生物的激发态失活机理。计算结果表明:相邻苯环的光环化过程是TPE-4mM激发态失活的主要途径,而这一过程在TPE-4oM中受到阻碍。我们期望这一发现为新型AIE分子的设计提供更多理论依据和理论指导。

关键词： AIE 四苯乙烯衍生物静态电子结构计算非绝热动力学模拟光环化

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Geoscience Frontiers 2020年第3期11卷 885-893页

作者： Tom Wise Stephan thiel Geological Survey of South Australia Department for Energy and MiningAdelaideSA5005Australia School of Earth and Environmental Sciences University of AdelaideAdelaideSA5005Australia

Over the last two decades,co-located seismic and magnetotelluric(MT) profiles provided fundamental geophysical data sets to image the Australian *** their complimentary nature,the data are processed and often interpreted separately without common processes in *** here qualitatively compare 2 D resistivity inversion models derived from MT and seismic reflection profiles across a region of Archean-Proterozoic Australia to address the causes of variations in seismic response and anomalous conductivity in the *** find that there exists a spatial association between regions of low reflectivity in seismic sections and low resistivity in co-located2 D MT modelled *** relationships elucidate possible signatures of past magmatic and fluid-related *** on their diffuse or discrete character,we hypothesize these signatures signify fossil melting of the crust due to mafic underplating,magma movement or hydrothermal fluid flow through the *** approach discussed herein is a process-oriented approach to interpretation of geophysical images and a significant extension to traditional geophysical methods which are primarily sensitive to a singular bulk rock property or state.

关键词： Magnetotellurics Seismic reflection Resistivity

THE NUCLEAR TRACK DEPTH PROFILE OF THE JILIN METEORITE

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Science China Chemistry 1989年第5期32卷 594-603页

作者： K.thiel 胡瑞英 Nuclear Chemistry Department University of Kln 5000 Kln 1 FRG Institute of Geochemistry Academia Sinica Guiyang

Using 43 documented drill core samples of the H_5-chondrite 'Jilin' the depth profile of GCR-and fission track densities was established. The track profile essentially reflects the GCR-track record of the second (4π-) irradiation stage of 'Jilin'. Relics of the track record of the first (2π-) exposure are indicated by a deviation from the theoretical depth profile of the 4π-exposure. No Pu-244 fission is observed ia the fission track background near the meteorite center. The atmospheric ablation thickness of the two drill cores A and B normal and parallel to the assumed surface of the 'Jilin' parent body was found to be 11±4 cm, respectively. A minimum shielding depth of the 'top' part of core A during the 2π-exposure is estimated to be～30 cm. Near surface deviations of the experimental track data from theory are ascribed to a short-term moderate heating event (equivalent to 24h,～370℃) no more than 0.4 Ma ago. The resulting partial track annealing in a surface layer of ～15—20 cm thickness of the preatmospheric body can explain the lack of GCR-tracks in Jilin samples from very shallow depths that are based on ^(60)Co measurements.

关键词： H5-chcndrite "Jilin" fission track profile olivine.

Polyolefin-nanocomposites with special properties by in-situ polymerization

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Frontiers of Chemical Science and Engineering 2018年第3期12卷 555-563页

作者： walter Kaminsky Institute for Technical and Macromolecular Chemistry Department of Chemistry University of Hamburg 20146 Hambtlrg Germany

Exceptionally strong polyolefin nanocompo- sites are synthesized by in-situ polymerization using soluble metallocene/methylaluminoxane （MAO） as cata- lysts in a two-step process. First, the soluble metallocene/ MAO or other single site catalysts are absorbed on the surface of the nanofillers. Then by addition of ethene or propene, a polyolefin film is formed, covering the nanoparticles, layered silicates, or fibers. The resulting polyethylene and polypropylene nanocomposites are characterized by better physical and chemical properties such as stiffness, gas barrier properties, degradation temperatures, and crystallization rates. They show better mechanical properties than materials produced by mechan- ical blending. The thickness of the polyolefin can be controlled by the pressure of ethene or propene and by the polymerization time. Carbon fibers and carbon nanotubes are covered with isotactic or syndiotactic polypropylene. Because of the hydrophobic character of the carbon surface, the polymer is drawn on the fiber. This leads to a reinforced combined polymer with special properties. The crystallization temperature is 10℃ higher and therefore the crystallization rate up to 20 times faster than that of pure syndiotactic polypropylene. The form stability increases by 100% if 3 wt-% of carbon nanotubes are incorporated.

关键词： polyolefin nanocomposites metallocenes methylalttminoxane

Beware of gastric tube in esophagectomy after gastric radiotherapy:A case report

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World Journal of Clinical Cases 2022年第17期10卷 5854-5860页

作者： Can Yurttas Doerte Wichmann Cihan Gani Malte N Bongers Stephan Singer Christian thiel Alfred Koenigsrainer Karolin thiel Department of General Visceral and Transplant SurgeryUniversity Hospital of TuebingenTuebingen 72076Germany Department of Radiooncology University Hospital of TuebingenTuebingen 72076Germany Department of Diagnostic and Interventional Radiology University Hospital of TuebingenTuebingen 72076Germany Department of Pathology University Hospital of TuebingenTuebingen 72076Germany

BACKGROUND Gastric tube formation and pull-up is the most common technique of reconstruction following esophagectomy for esophageal *** previous treatment with radiotherapy for gastric mucosa-associated lymphoid tissue(MALT)-lymphoma restricts suitability of the stomach for anastomosis to the esophagus is *** SUMMARY A 57-year-old man underwent sequential chemotherapy and radiotherapy for gastric MALT-lymphoma seven years prior to diagnosis of esophageal *** without neoadjuvant treatment was recommended by the multidisciplinary tumor board due to early tumor stage[uT1(sm2)uN+cM0 according to TNM-classification of malignant tumors,8^(th) edition]without lymph node *** invasive esophageal resection with esophagogastrostomy was *** to gastric tube necrosis with anastomotic leakage on the twelfth postoperative day,diverting resection with construction of a cervical salivary fistula was *** recovery facilitated colonic interposition without any complications six months *** This case report may represent the start for further investigation to know if it is reasonable to refrain from esophagogastrostomy in patients with a long interval between gastric radiotherapy and surgery.

关键词： Esophageal cancer Mucosa-associated lymphoid tissue lymphoma Esophagogastrostomy Cervical fistula Colonic interposition Case report

Assessing Possibilities and Limitations for Biomarker Analyses on Outcrop Samples:A Case Study on Carbonates of the Shibantan Member (Ediacaran Period, Dengying Formation, South China)

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Acta Geologica Sinica(English Edition) 2014年第6期88卷 1696-1704页

作者： Jan-Peter DUDA Volker thiel Joachim REITNER Martin BLUMENBERG Geoscience Centre Geobiology Group Georg-August-University GttingenGoldschmidtstr.337077 Gttingen Germany Federal Institute for Geosciences and Natural Resources (BGR) Stilleweg 2 30655 Hannover Germany

The Shibantan Member（Dengying Formation, South China） represents one of only two carbonate settings with Ediacara-type organisms and offers a rare opportunity to study the biogeochemistry of these ecosystems. To evaluate possibilities and limitations for future biomarker studies on fossil-bearing outcrop samples of the Shibantan Member, we analysed the spatial distribution of hydrocarbons in extractable organic matter（i.e. bitumen） on a millimetre scale. Our study demonstrates that the sample and most likely also other rocks from the same setting are contaminated with petroleum-derived compounds that bear the potential for erroneous interpretations in palaeo-reconstructions. The contamination was revealed by distribution patterns and amounts of extractable n-alkanes and acyclic isoprenoids. The contamination is linked to the external weathering surfaces but also to cracks within the rock, and the extent most likely depends on concentration gradients between these contamination sources. Here we show that contamination can successfully be distinguished from syngenetic signals obtained from non-extractable organic matter（i.e. kerogen） using catalytic hydropyrolysis（Hy Py）. However, we observed that decalcification is necessary to achieve sufficient yields of kerogen-bound hydrocarbons and to avoid artificial alteration of the biomarker signals due to matrix effects.

关键词： Ediacaran biomarkers contamination syngeneity slice-experiments catalytic hydropyrolysis(HyPy)

Occurrence of organochlorine pollutants in the eggs and dropping-amended soil of Antarctic large animals and its ecological significance

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Science China Earth Sciences 2007年第7期50卷 1086-1096页

作者： Vetter walter Friedrich-Schiller-Universitt Jena Lehrbereich LebensmittelchemieDornburger Str. 25D-07743 JenaGermany

Persistent organochlorine pollutants (POPs) are analyzed for the dropping-amended soils from the habitats of Antarctic seabirds and seals in Fildes Peninsula and Ardley Island. The concentration ranges are 0.21 to 3.85 ng/g for polychlorinated biphenyls (ΣPCBs),0.09 to 2.01 ng/g for organochlorine pesticides (ΣDDT),and 0.06 to 0.76 ng/g for hexachlorocyclohexanes (HCHs). Among these,hepata-chlorobiphenyls,hexachlorobiphenyls,p,p′-DDE and α-HCH compounds are dominant. The concentra-tion ranges of ΣPCB,DDT and HCH in the eggs of skuas were 91.9―515.5 ng/g,56.6―304.4 ng/g and 0.5―2.0 ng/g respectively; those in the eggs of penguins were 0.4―0.9 ng/g,2.4―10.3 ng/g and 0.1― 0.4 ng/g; and those in the eggs of giant petrel were 38.1―81.7 ng/g,12.7―53.7 ng/g and 0.5―1.5 ng/g respectively. The dominant POP compounds in the eggs are PCB180,PCB153,p,p′-DDE and hexa-chlorobenzene (HCB). The present study shows that the concentration of POPs in the sea-bird-inhabited-dropping-amended soil varies with the extent of predation and nest occupancy of dif-ferent seabird populations. Statistical analysis on the POP concentrations from the different seabird eggs implies that the difference in the bio-concentration levels of the birds depends on the bio-habits of the species,such as the range of activity,distance of immigration,feeding pattern,and nest occupation. Among these,the most important factor is the location of the seabirds in the food chain and their feeding pattern. This shows that POPs accumulated in the seabirds resulted from the bio-concentration through the food chain. In addtion,210Pb dating for the dropping-amended soils (AD1-a and AD2) was performed,which provided the POP accumulation rate and the historic record for the soil profile. It indicates that POP will continuously affect the Antarctic ecosystem for a long time.

关键词： persistent organochlorine pollutant animal habitats dropping-amended soil seabird egg Antarctica