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Monomer-activated Copolymerization of Ethylene Oxide and Epichlorohydrin: In Situ Kinetics Evidences Tapered Block Copolymer Formation

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Chinese Journal of Polymer Science 2019年第9期37卷 912-918页

作者： Ann-Kathrin Danner Daniel Leibig lea-marie vogt Holger Frey Institute of Organic Chemistry Johannes Gutenberg- Universitat Mainz Duesbergweg 10-14 55128 Mainz Germany Graduate School Materials Science in Mainz Staudinger Weg 9 55128 Mainz Germany

The monomer-activated anionic ring-opening copolymerization (AROP) of ethylene oxide (EO) and epichlorohydrin (ECH) using tetraoctylammonium bromide as an initiator and triisobutylaluminum (i-Bu3Al) as an activator was studied. The properties of the copolymers as well as the microstructure have been analyzed in detail via an in situ NMR kinetics study. The statistical copolymers exhibited molecular weights ranging from 2350 g·mol^-1 to 38000 g·mol^-1 (measured by SEC, PEG-standards) and moderate dispersities of 1.27-1.44. The thermal property tests revealed both a glass transition and melting for all copolymers, supporting a block-like nature. Applying in situ NMR kinetic measurements, the reactivity ratios of EO and ECH were determined to be strongly disparate, i.e., rEo = 9.2 and rECH = 0.10. This shows that the simple one-pot statistical anionic copolymerization of EO and ECH via the monomer-activated AROP resulted in the formation of strongly tapered, block-like structures. Furthermore, post-polymerization functionalization of the reactive chloromethyl groups by nucleophilic displacement was investigated for the copolymers. Copolymerization of EO and ECH offers a broad platform for further functionalization and therefore the possibility to prepare a variety of multifunctional PEGs.

关键词： Epichlorohydrin Polymerization Ring-opening Copolymerization Reactivity ratios Epoxide

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Risk of conduction disturbances following different transcatheter aortic valve prostheses:the role of aortic valve calcifications

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Journal of Geriatric Cardiology 2022年第3期19卷 167-176页

作者： Francesco Pollari Ferdinand vogt Irena Großmann Jill Marianowicz marie Claes Steffen Pfeiffer Johannes Schwab Theodor Fischlein Cardiac Surgery Cardiovascular CenterKlinikum NürnbergParacelsus Medical UniversityNurembergGermany Cardiology Cardiovascular CenterKlinikum NürnbergParacelsus Medical UniversityNurembergGermany Radiology Klinikum NürnbergParacelsus Medical UniversityNurembergGermany

OBJECTIVES To assess the impact of prosthesis choice and aortic valve calcifications on the occurrence of conduction disturb-ances after transcatheter aortic valve implantation(TAVI).METHODS We retrospectively analyzed the preoperative clinical characteristics,electrocardiograms,contrast-enhanced mul-tidetector computed tomography scans and procedural strategies of patients who underwent TAVI in our center between January 2012 and June *** of calcium volume was performed for each aortic cusp above(aortic valve)and below(left ventricular outflow tract,LVOT)the basal *** analysis was performed to evaluate risk factors for the onset of new bundle branch block(BBB),transient and permanent atrioventricular block(tAVB,pAVB).RESULTS A total of 569 patients were included in the *** different prostheses were implanted(Edwards Sapien XT,n=162;Edwards Sapien 3,n=240;Medtronic CoreValve,n=27;Medtronic CoreValve Evolut R,n=21;Symetis Acurate,n=56;Sy-metis Acurate neo,n=63).The logistic regression analysis for BBB showed association with baseline left anterior *** logistic regression for tAVB,found the prior valvuloplasty and the balloon post-dilatation associated with the *** left and right BBB,degree of oversizing,and LVOT calcification beneath the non-coronary cusp were associated with *** the prosthesis model,nor the use of a self-expandable prosthesis showed statistical significance with the above-men-tioned outcomes on univariate *** LVOT calcification beneath the non-coronary cusp,baseline left anterior hemiblock,right BBB,balloon post-dilatation,prior valvuloplasty and oversizing are independently associated with postprocedural conduction disturbances after *** of a self-expandable prosthesis may show a lower incidence of AVB,if applied in lower calcified aortic valves.

关键词： aortic balloon conduction

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Three‐terminal perovskite/integratedbackcontactsilicon tandem solar cells under low light intensity conditions

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Interdisciplinary Materials 2022年第1期1卷 148-156页

作者： Hiroyuki Kanda Valentin Dan Mihailetchi marie-Estelle Gueunier-Farret Jean-Paul Kleider Zakaria Djebbour Jose Alvarez Baranek Philippe Olindo Isabella Malte R.vogt Rudi Santbergen Philip Schulz Fiala Peter Mohammad K.Nazeeruddin James P.Connolly Group for Molecular Engineering of Functional Materials Ecole Polytechnique Federale de LausanneValais WallisSionSwitzerland International Solar Energy Research Center ISC-Konstanz E.V.KonstanzGermany Centrale Supelec CNRSLaboratoire de Genie Electrique et Electronique de ParisUniversite Paris-SaclayGif-sur-YvetteFrance CNRS Laboratoire de Genie Electrique et Electronique de ParisSorbonne UnibversiteParisFrance CNRS Institut Photovoltaique d'Île de France(IPVF)PalaiseauFrance Department EFESE EDF Lab Paris‐SaclayEDF R&DPalaiseauFrance Delft University of Technology(TU Delft) DelftThe Netherlands Photovoltaics and Thin-Film Electronics Laboratory Ecole Polytechnique Federale de LausanneNeuchatelSwitzerland

The current climate and energy crisis urgently needs solar cells with efficiencies above the 29% single junction efficiency ***/perovskite tandem solar cells are a solution,which is attracting much *** silicon/perovskite tandem cells in 2-terminal and 4-terminal configurations are well documented,the three-terminal concept is still in its *** has significant advantages under low light intensities as opposed to concentrated sunlight,which is the critical factor in designing tandem solar cells for low-cost terrestrial *** study pre-sents novel studies of the sub-cell performance of the first three-terminal perovskite/silicon selective band offset barrier tandem solar cells fabricated in an ongoing research *** study focuses on short circuit current and operating voltages of the subcells under light intensities of one sun and *** studies show that the perovskite bulk carrier lifetime is insensitive to illumination,while the silicon cell's lifetime decreases with decreasing light *** combination of perovskite and silicon in the 3T perovskite-silicon tandem therefore reduces the sensitivity of V_(OC) to light intensity and maintains a relatively higher V_(OC) down to low light intensities,whereas silicon single-junction cells show a marked *** technological advantage is proposed as a novel advantage of three-terminal perovkite/silicon solar cells for low light intensities of one sun or less.

关键词： low light intensity conditions perovskite solar cells tandem solar cells three-terminal perovskite/Si solar cells

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Assessing GastroPanel serum markers as a non-invasive method for the diagnosis of atrophic gastritis and <i>Helicobacter pylori</i>infection

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Open Journal of Gastroenterology 2012年第3期2卷 113-118页

作者： Dominique Noah Noah marie Claire Okomo Assoumou Servais Albert Fiacre Eloumou Bagnaka Guy Pascal Ngaba Ivo Ebule Alonge lea Paloheimo Oudou Njoya Biohit Helsinki Finland District Hospital of Bonassama Faculty of Medicine and Pharmaceuticals Sciences University of Douala Douala Cameroon Douala General Hospital Faculty of Medicine and Pharmaceuticals Sciences University of Douala Douala Cameroon Faculty of Medicine and Biomedical Sciences University of Yaounde Yaounde Cameroon University Teaching Hospital Yaounde Yaounde Cameroon Yaounde Central Hospital Faculty of Medicine and Pharmaceuticals Sciences University of Douala Douala Cameroon

Gastric colonization by Helicobacter pylori increases the risk of gastric disorders, including atrophic gastritis which can be diagnosed based on levels of serum biomarkers like Gastrin and Pepsinogen. We therefore examined the efficacy of a serological-based method namely GastroPanel Blood kit, in diagnosing and scoring gastritis associated to Helicobacter pylori infection. Patients with dyspeptic symptoms were prospectively recruited on voluntary basis at the Yaounde Central Hospital and University Teaching Hospital, from March to July 2011. The degree of atrophy was classified according to levels in patient serum of pepsinogens I and II (PGI and PGII) and Gastrin 17 (G17) and compared with histological profiles as reference method. A specific ELISA test was used for the detection of H. pylori IgG antibodies. In total, 86 volunteers from 21 to 83 years old (mean = 46.4 ± 3.3) were enrolled, including 74.4% of women and 25.6% of men. The prevalence of gastritis was statistically similar between Gastro Blood Panel test and histology used as reference method (89.5% versus 83.7%: p > 0.20). Diagnosis based on serum makers showed high sensitivity (93.1%) in comparison with the reference method. However, the serological based method has diagnosed more atrophic gastritis than the reference (17.4% versus 7.0%: p 0.05). Furthermore, the prevalence of H. pylori infection did not differ significantly between serological method (84.9%) and reference method (81.4%). These results suggest that diagnosis of atrophic gastritis and H. pylori infection obtained with an optional serological method (GastroPanel) is in a strong agreement with the biopsy findings, and thus can be a useful non endoscopic assessment of stomach mucosal atrophy in patients with dyspepsia.

关键词： Diagnosis Atrophic Gastritis Helicobacter pylori Pepsinogen Gastrin

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Standard Model and Related Topics

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Chinese Physics C 2016年第10期40卷 132-348页

作者： C.Patrignani K.Agashe G.Aielli C.Amsler M.Antonelli D.M.Asner H.Baer Sw.Banerjee R.M.Barnett T.Basaglia C.W.Bauer J.J.Beatty V.I.Belousov J.Beringer S.Bethke H.Bichsel O.Biebel E.Blucher G.Brooijmans O.Buchmueller V.Burkert M.A.Bychkov R.N.Cahn M.Carena A.Ceccucci A.Cerri D.Chakraborty M.-C.Chen R.S.Chivukula K.Copic G.Cowan O.Dahl G.D'Ambrosio T.Damour D.de Florian A.de Gouvea T.DeGrand P.de Jong G.Dissertori B.A.Dobrescu M.D'Onofrio M.Doser M.Drees H.K.Dreiner D.A.Dwyer P.Eerola S.Eidelman J.Ellis J.Erler V.V.Ezhela W.Fetscher B.D.Fields B.Foster A.Freitas H.Gallagher L.Garren H.-J.Gerber G.Gerbier T.Gershon T.Gherghetta A.A.Godizov M.Goodman C.Grab A.V.Gritsan C.Grojean D.E.Groom M.Grnewald A.Gurtu T.Gutsche H.E.Haber K.Hagiwara C.Hanhart S.Hashimoto Y.Hayato K.G.Hayes A.Hebecker B.Heltsley J.J.Hernandez-Rey K.Hikasa J.Hisano A.Hcker J.Holder A.Holtkamp J.Huston T.Hyodo K.Irwin J.D.Jackson K.F.Johnson M.Kado M.Karliner U.F.Katz S.R.Klein E.Klempt R.V.Kowalewski F.Krauss M.Kreps B.Krusche Yu.V.Kuyanov Y.Kwon O.Lahav J.Laiho P.Langacker A.Liddle Z.Ligeti C.-J.Lin C.Lippmann T.M.Liss L.Littenberg K.S.Lugovsky S.B.Lugovsky A.Lusiani Y.Makida F.Maltoni T.Mannel A.V.Manohar W.J.Marciano A.D.Martin A.Masoni J.Matthews U.-G.Meiβner D.Milstead R.E.Mitchell P.Molaro K.Mnig F.Moortgat M.J.Mortonson H.Murayama K.Nakamura M.Narain P.Nason S.Navas M.Neubert P.Nevski Y.Nir K.A.Olive S.Pagan Griso J.Parsons J.A.Peacock M.Pennington S.T.Petcov V.A.Petrov A.Piepke A.Pomarol A.Quadt S.Raby J.Rademacker G.Raffelt B.N.Ratcliff P.Richardson A.Ringwald S.Roesler S.Rolli A.Romaniouk L.J.Rosenberg J.L.Rosner G.Rybka R.A.Ryutin C.T.Sachrajda Y.Sakai G.P.Salam S.Sarkar F.Sauli O.Schneider K.Scholberg A.J.Schwartz D.Scott V.Sharma S.R.Sharpe T.Shutt M.Silari T.Sjstrand P.Skands T.Skwarnicki J.G.Smith G.F.Smoot S.Spanier H.Spieler C.Spiering A.Stahl S.L.Stone Y.Sumino T.Sumiyoshi M.J.Syphers F.Takahashi M.Tanabashi K.Terashi J.Terning R.S.Thorne L.Tiator M.Titov N.P.Tkachenko N.A.Trnqvist D.Tovey G.Valencia R.Van de Water N.Varelas G Particle Data Group Universita di Bologna and INFN Dip.Scienze per la Qualita della Vita University of Maryland Department of Physics College Park Universit degli Studi di Roma "Tor Vergata" Albert Einstein Center for Fundamental Physics Universitt Bern Stefan Meyer Institute for Subatomic Physics Austrian Academy of Sciences Lab.Nazionali di Frascati dell'INFN Pacific Northwest National Laboratory Department of Physics and Astronomy University of Oklahoma University of Louisville Physics Division Lawrence Berkeley National Laboratory CERN European Organization for Nuclear Research Department of Physics The Ohio State University COMPAS Group Institute for High Energy Physics Max-Planck-Institute of Physics Department of Physics University of Washington Ludwig-Maximilians-Universitt Fakultt fr Physik Enrico Fermi Institute and Department of Physics University of Chicago Department of Physics Columbia University High Energy Physics Group Blackett Laboratory Imperial College Jefferson Lab Department of Physics University of Virginia Fermi National Accelerator Laboratory Kavli Institute for Cosmological Physics University of Chicago Department of Physics and Astronomy University of Sussex Department of Physics Northern Illinois University Department of Physics and Astronomy University of California Michigan State University Dept.of Physics and Astronomy Department of Physics Royal Holloway University of London INFN-Sezione di Napoli Complesso Universitario Monte Sant'Angelo Institut des Hautes Etudes Scientifiques International Center for Advanced Studies(ICAS) UNSAM Department of Physics and Astronomy Northwestern University Department of Physics University of Colorado at Boulder Nikhef P.O.Box 41882 1009 DB Amsterdam and University of Amsterdam Institute for Particle Physics ETH Zurich University of Liverpool Department of Physics Oliver Lodge Lab Physikalisches Institut Universitt Bonn Helsinki Institute of Physics University of Helsinki Department of Physics Budker Institute of Nuclear Physics SB RAS Novosib

The Review summarizes much of particle physics and *** data from previous editions,plus 3,062 new measurements from 721 papers,we list,evaluate,and average measured properties of gauge bosons and the recently discovered Higgs boson,leptons,quarks,mesons,and *** summarize searches for hypothetical particles such as supersymmetric particles,heavy bosons,axions,dark photons,*** the particle properties and search limits are listed in Summary *** also give numerous tables,figures,formulae,and reviews of topics such as Higgs Boson Physics,Supersymmetry,Grand Unified Theories,Neutrino Mixing,Dark Energy,Dark Matter,Cosmology,Particle Detectors,Colliders,Probability and *** the 117 reviews are many that are new or heavily revised,including new reviews on Pentaquarks and Inflation.

关键词： Standard Model and Related Topics

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