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Co-aromatization of methane and hexane over Pt encapsulated in ZSM-5 zeolite and the electronic effect of K promoters

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Science China Chemistry 2024年第3期67卷 1017-1027页

作者： Bei Liu fan wang Xiaomeng Dou Pengfei Li Hongwei Xiang Yong Yang Peng He State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China Department of Chemistry Tsinghua UniversityBeijing 100084China National Energy r&D Center for Coal to Liquid fuels Synfuels China Technology Co.Ltd.Beijing 101407China University of Chinese Academy of Sciences Beijing 101408China Leibniz-institut für Katalyse e.V.an der universitat rostock Rostock 18059Germany

The co-aromatization of methane with higher hydrocarbons represents a promising route to valorize methane, an abundant but underexploited carbon resource. In this study, we elucidate a novel approach to enhance the catalytic co-aromatization of hexane and methane by confining Pt within zeolite catalysts and modulating its electron density. Our findings show that encapsulating Pt within MfI structure is pivotal for activating the feedstock and fostering the formation of aromatic products. Interaction between K atoms and the silanol nest forms siloxy groups which are critical for the stabilization of Pt species. Tuning the K content in PtSn@MfI catalysts adeptly alters the electronic configuration of Pt clusters. This modification is corroborated by infrared and X-ray photoelectron spectroscopy analysis, and density functional theory calculations. remarkably, the catalyst with 0.8 wt% K exhibits an optimal Pt electron density, driving its superior efficacy in the co-aromatization reaction, converting 0.78 mol of methane for each mole of hexane processed. By employing ~(13)C isotopic labeling and solid-state NMr studies, we demonstrate the participation of methane in the adsorbed species inside the zeolite channel and its incorporation to the benzyl site of the substitute group and phenyl rings in aromatic compounds, underscoring the importance of Pt encapsulation.

关键词： Pt encapsulation MfI zeolite methane activation co-aromatization ^(13)C solid-state NMr

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Biomechanische Untersuchungsergebnisse ber die verbesserte Verankerung von Pedikelschraubenmit resorbierbarem Zement in menschenlichen wirbelk rpern

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Journal of Huazhong University of Science and Technology(Medical Sciences) 2001年第1期21卷 48-51页

作者：邵景范罗永湘 Luo Yongxiang Lutz Claes Lothar Kinzl Abteilung für Chirurgie Tongji KlinikTongji medizinisches institutHuazhong Universitat für Wissenschaft und Technik Abteilung für Unfallchirurgie Hand-und Wiederherstellungschirurgie der Universitat UlmDeutschland Abteilung für Unfallchirurgische forschung und Biomechanik der universitat Ulm Deutschland

Die Prim rstabilit t von Pedikelschrauben im Knochen h ngt in hohem Masse von der Knochendichte ab. Die Augmentation mit Zement ist ein klinisch einsetzbares Verfahren, um die Schrauben Verankerung im osteoporotischen Knochen zu *** dieser Studie wurde eine neuartiges resorbierbares Knochenersatzmaterial (α BSM TM ) für diese Augmentation benutzt. Biomechanische Testungen wurden in vitro bei 16 Lendwirbelk rpern (L3-L5) aus 6 Individuen(75,2±13,7 Jahre) durchgeführt. Vor der biomechanischen Testung wurde bei allen Pr paraten die trabekul re Knochendichte mittels pQCT gemessen und beide Pedikel mit USS Pedikelschrauben (5,0 mm × 45 mm) besetzt, von welchen eine mit α BSM TM augmentiert war. Beim axialen Auszugstest wurden die maximale axiale Auszugskraft (f max) sowie die Energieaufnahme bestimmt. der Medianwert der f max stieg beim Auszugstest durch die Zementierung mit α BSM TM um 80 % von 370 N (ohne Zement) auf 665 N (mit Zement). Die Energieaufnahme bis zum Erreichen der f max (E f max) und bei Dislokation bis 2,0 mm (E 2 mm) steigerte sich ebenfalls um 83 % und 68 %. Die Unterschiede waren signifikant. (wilcoxon′s Test, P reisskrafte f max (ohne oder mit Zement) korrelierten eng mit der Knochendichte ( r =0,9056 und r =0,9585). Unsere resultate zeigen, da eine Augmentation mit dem α BSM TM die primare Stabilitat von Pedikelschrauben verbessern kann. der Effekt scheint auf einer Optimierung der Kontaktfl che und einer Aussteifung der schraubennahen Spongiosa zu beruhen. Das Material k nnte geeignet sein, die Verankerung von Pedikelschrauben bei osteoporotischen Patieten zu verbessern.

关键词： Biomechanik Zement Pedikelschraube Stabilit t wirbelk rper

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Impact of Molecular Shape on Supramolecular Copolymer Synthesis in Seeded Living Polymerization of Perylene Bisimides

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CCS Chemistry 2019年第5期1卷 598-613页

作者： wolfgang wagner Marius wehner Vladimir Stepanenko frank wurthner Center for Nanosystems Chemistry(CNC)and Bavarian Polymer institute(BPI) Universitat WürzburgTheodor-Boveri-WegWürzburg 97074Germany institut fur Organische Chemie Universitat WürzburgWurzburg 97074Germany

Supramolecular polymerization properties have been studied for a series of perylene bisimide(PBI)dyes containing identical hydrogen-bonding amide groups in imide positions but variable number or size of alkoxy substit... 详细信息

关键词： supramolecular polymer self-assembly living supramolecular polymerization block copoly-mers perylene bisimides

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Crystal morphology of sucrose influenced by rotation axes parallel to growth planes

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Chinese Science Bulletin 2000年第16期45卷 1468-1471页

作者： C.Silber H.follner institut für Mineralogie und Mineralische rohstoffe der Technischen universitat Clausthal Adolph-Roemer-Str.2AD-38678 Clausthal-ZellerfeldDeutschlandInstitut Für Mineralogie und Mineralische Rohstoffe der Technischen Universitat ClausthalAdolph-Roemer-Str.2AD-38678 Clausthal-ZellerfeldDeutschland

Three different types of growth forms of sucrose (P21) were found by calculating with the fourier transform method of crystal morphology. The observed central distances of the (100) and (001) faces are smaller than those calculated. It will be shown that the two-fold screw axis, which runs parallel to these faces, influences the rate of growth. The effectiveness of these symmetry elements is relative to the rotation angle around the face normal.

关键词： sucrose crystal growth mechanism symmetry dependent growth fourier transform method of morphology.

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由链球菌引起的肉芽肿性心内膜炎

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德国医学 1995年第1期12卷 58-60页

作者： A.M.Gassel M.M.Ott D.Piridou-Bagatzouni K.Sandhage M.Lebert H.K.Müller-Hermelink 阮幼冰 institut fü Pathologie der Universtiat würzburg institut für hvgiene der universitat würzburg universitats-Kinderklinik würzburg Medizinische Klinik des Juliusspitals würzburg 同济医科大学

绿色链球菌为感染性心内膜炎的最常见病因,本病的30％系由其引起,因此菌属正常口腔菌丛,故在心瓣膜感染前常先有牙、口腔、颌的感染史,基于其相对低毒性,故大多系侵入先前已损伤的心瓣膜,并导致典型的亚急性溃疡息肉型心内膜炎。组织学... 详细信息

绿色链球菌为感染性心内膜炎的最常见病因,本病的30％系由其引起,因此菌属正常口腔菌丛,故在心瓣膜感染前常先有牙、口腔、颌的感染史,基于其相对低毒性,故大多系侵入先前已损伤的心瓣膜,并导致典型的亚急性溃疡息肉型心内膜炎。组织学上见有心瓣膜受累处坏死,肉芽组织及血栓性疣赘物形成。炎性细胞通常以粒细胞为主。以组织细胞性或肉芽肿性反应为主者迄今仅见于Behcet的一例报道,而在感染性心内膜炎则至今尚未见报告。本文报道二例抗菌素类药物治疗不敏感的感染性心内膜炎伴组织细胞及部分肉芽肿反应的病例。

关键词：心内膜炎肉芽肿链球菌病例报告

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rationally connected varieties -On a conjecture of Mumford

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Science China Mathematics 2017年第6期60卷 1019-1028页

作者： LAZIC Vladimir PETErNELL Thomas Mathematisches institut Universitat Bonn Bonn 53115 Germany Mathematisches institut Universitat Bayreuth Bayreuth 95440 Germany

we establish a conjecture of Mumford characterizing rationally connected complex projective manifolds in several cases.

关键词： rationally connected varieties Mumford conjecture non vanishing conjecture abundance

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Use of pCONUS HPC for the treatment of unruptured wide- necked bifurcation aneurysms: early clinical experience using single antiplatelet therapy

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Stroke & Vascular Neurology 2021年第1期6卷 57-64页

作者： Marta Aguilar Perez Victoria Hellstern Carmen Serna Candel Christina wendl Hansjorg Bazner Oliver Gansladt Hans Henkes Neuroradiologische Klinik NeurozentrumKlinikum StuttgartStuttgartGermany institut fur rontgendiagnostik Zentrum fur NeuroradiologieFakultat für Medizin der Universitat RegensburgRegensburgGermany Neurologische Klinik NeurozentrumKlinikum StuttgartStuttgartGermany Neurochirurgische NeurozentrumKlinikum StuttgartStuttgartGermany Medizinische fakultat Universitat Duisburg-EssenEssenGermany

Background In recent years,a growing number of stents and stent-like devices have become available to facilitate the treatment of challenging ***,the need for dual antiplatelet therapy can limit their use,especially in ruptured *** hydrophilic polymer coating(pHPC,phenox)is a novel glycan-based multilayer polymer that reduces platelet *** study aims to report our initial experience using the pCONUS HPC device for the treatment of unruptured wide-necked bifurcation aneurysms(wNBA)using acetylsalicylic acid(ASA)as single antiplatelet therapy(SAPT).Methods we retrospectively identified all patients who were treated with the pCONUS HPC for unruptured wNBA in a multi-staged procedure using ASA as *** were made of periprocedural complications,clinical outcome and angiographic and clinical *** we identified 15 patients with 15 *** average age was 69 years old(range,41-76).Seven aneurysms were located in the middle cerebral artery,five in the anterior communicating artery,two at the basilar tip and one in the posterior communicating *** post-treatment angiography showed five aneurysms with modified raymond-roy classification(mrrC)grade Ⅰ and four aneurysms with mrrC grade Ⅱ.There were no haemorrhagic *** patients developed thrombus formation during the second treatment session,all of them completely resolving after administration of glycoprotein Ⅱb/Ⅲa *** follow-up data were available for 10 patients and showed adequate occlusion(mrrC Ⅰ or Ⅱ)in eight aneurysms(80%).In-stent stenosis was observed in one patient whereas two patients showed de novo stenosis in one of the efferent *** This early experience on the use of the pCONUS HPC device suggests that it can be useful for treating unruptured wNBA under ASA as *** investigation with a randomised treatment registry and larger cohort is needed.

关键词： treatment bifurcation HPC

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Teleportation with an Arbitrary Mixed resource as a Trace-Preserving Quantum Channel

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Communications in Theoretical Physics 2002年第3期38卷 301-304页

作者： Sergio Albeverio fEI Shao-Ming YANG wen-Li institut fiir Angewandte Mathematik Universitat Bonn D-53115 Germany Institut fiir Angewandte Mathematik Universitat Bonn D-53115 Germany Department of Mathematics Capital Normal University Beijing 100037 China Physikalisches Institut der Universitat Bonn 53115 Bonn Germany institute of Modern Physics Northwest University Xi'an 710069 China

General conditions are given in order to perform a perfect teleportation process in the case where theHilbert spaces involved have different dimensions. An explicit expression is obtained for the quantum channel associatedwith the standard teleportation protocol To with an arbitrary mixed state resource. The transmission fidelity of thecorresponding quantum channel is given.

关键词： teleportation, fidelity

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Dual-Targeting of Arabidopsis 6-Phosphogluconolactonase 3 （PGL3）to Chloroplasts and Peroxisomes Involves Interaction with Trx m2 in the Cytosol

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Molecular Plant 2014年第1期7卷 252-255页

作者： Christian Holscher Tanja Meyer Antje von Schaewen institut for Biologie und Biotechnologie der Pflanzen Westfalische Wilhelms-Universitat Munster Schlossgarten 3 48149 Munster Germany

The oxidative pentose-phosphate pathway （OPPP） represents a central branch of cellular metabolism emanating from glucose-6-phosphate （G6P） to provide reductive power （NADPH） and sugar phosphates for anabolic biosyntheses. In plant cells, the oxidative OPPP branch is found in the cytosol and in plastids, consisting of glucose-6-phosphate dehydrogenase （G6PD）, 6-phosphogluconolactonase （PGL）, and 6-phosphogluconate dehydrogenase （6PGD）. These enzymes are encoded by small gene families in the nuclear genome, which, in Arabidopsis, comprise six G6PD, five 6-PGL, and three 6-PGD isoforms （Kruger and von Schaewen, 2003）. Specific targeting motifs at the C-terminus of 6-PGL and 6-PGD isoforms suggested that the OPPP may also occur in peroxisomes （reumann et al., 2004）.

关键词： Cytosol C-Terminus nuclear genome Plastid Peroxisomes 6-phosphogluconolactonase Gene families Plant cells chloroplasts Glucosephosphate Dehydrogenase Dual Glucose-6-Phosphate Arabidopsis sugar phosphates

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Concealed Integrity Monitoring for wireless Sensor Networks

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wireless Sensor Network 2011年第1期3卷 10-17页

作者： Bjorn Stelte Thomas Bühring institut für Technische Informatik Universitat der Bundeswehr MünchenNeubibergGermany

Nowadays, sensor networks are widely installed around the world. Typical sensors provide data for healthcare, energy management, environmental monitoring, etc. In the future sensors will become a part of critical infrastructures. In such a scenario the network operator has to monitor the integrity of the network devices, otherwise the trustworthiness of the whole system is questionable. The problem is that every integrity protocol needs a secure channel between the devices. Therefore, we will introduce a covert channel for hidden transportation of integrity monitoring messages. The covert channel enables us to hide integrity check messages embedded into regular traffic without giving potential attackers a hint on the used integrity protocol.

关键词： Covert Channel Integrity Monitoring wireless Sensor Network

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