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Chinese Journal of Polymer Science 2024年第4期42卷 501-510页

作者： Giovanni Ricci Anna Sommazzi france.co masi Alessandra Forni CNR-Istituto di Scienze e Tecnologie Molecolari“Giulio Natta”(SCITEC) via A.Corti 1220133MilanoItaly Viale Giovanni XXIII 34 I-28100NovaraNOItaly Via Galvani 7 I-26866Sant’Angelo LodigianoLOItaly CNR-Istituto di Scienze e Tecnologie Molecolari“Giulio Natta”(SCITEC) via C.Golgi 1920133MilanoItaly

Several novel cobalt dichloride complexes with amino-phosphine bidentate ligands were synthesized and *** some of them single crystals were obtained and their molecular structure was determined by X-ray diffraction *** the complexes were then used in combination with MAO for the polymerization of 1,3-butadiene,obtaining polymers with different structures(i.e.,predominantly 1,2 or cis-1,4)mainly depending on the type of ligand and on the MAO/co molar *** behavior of these novel catalysts was compared with that exhibited,in the polymerization of the same monomer,by the systems coCl_(2)(PR3)2-MAO and coCl_(2)(PRPh2)2-MAO(R=alkyl or cycloalkyl group),and by the systems based on cobalt dichloride complexes with various bi-and tridentate ligands(e.g.,diphosphines,bis-imines,pyridyl-imines,bis-iminopyridines).The comparison between the different systems allowed us to make some clarity about the actual and effective role played by the various types of ligands in the polymerization of conjugated dienes with catalytic systems coCl_(2)(L)-MAO,in which L=mono-,bi-,or tri-dentate ligand.

关键词： 1,3-Butadiene Stereospecific polymerization cobalt catalysts Regioselectivity Aminophosphine ligands Crystal structures Chelate rings

Theoretical Studies on Thermal Decomposition of Benzoyl Peroxide in Ground State

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Chemical Research in Chinese Universities 2003年第3期19卷 355-361页

作者： SUNCheng-ke YANGSi-ya LINXue-fei masi-yu LIZong-he DepartmentofChemistry BeijingNormalUniversityBeijing100875P.R.China；DepartmentofChemistryQujingNormalCollegeQujing655000P.R.China DepartmentofChemistry QujingNormalCollegeQujing655000P.R.China DepartmentofChemistry BeijingNormalUniversityBeijing100875P.R.China

Systematic studies of the thermal decomposition mechanism of benzoyl peroxide(BPO) in ground state, leading to various intermediates, products and the potential energy surface(PES) of possible dissociation reactions were made computationally. The structures of the transition states and the activation energies for all the paths causing the formation of the reaction products mentioned above were calculated by the AM1 semi-empirical method. This method is shown to to be one predict correctly the preferred pathway for the title reaction. It has been found that in ground state, the thermal decomposition of benzoyl peroxide has two kinds of paths. The first pathway PhC(O)O-OC(O)Ph→PhC(O)O · →Ph · +co 2 produces finally phenyl radicals and carbon dioxide. And the second pathway PhC(O)OO-C(O)Ph→PhC(O)OO · +PhC(O) · → PhC(O) · +O 2 →Ph · +co+O 2, via which the reaction takes place only in two steps, produces oxygen and PhC(O) · radicals, and the further thermal dissociation of PhC(O) · is quite difficult because of the high activation energy in ground state. The calculated activation energies and reaction enthalpies are in good agreement with the experimental values. The research results also show that also the thermal dissociation process of the two bonds or the three bonds for the benzoyl peroxide doesn′t take place in ground state.

关键词： Benzoyl peroxide Thermal decomposition Radical UAM1

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加肋钢悬臂支撑-底部钢板组合桥面拓宽技术

厦门大学学报（自然科学版） 2024年第4期63卷 743-752页

作者：谭万里余嘉康孙庄敬邓晖熊子多梅甘娜王东东中交一公局厦门工程有限公司福建厦门361021 厦门大学建筑与土木工程学院福建省滨海土木工程数字仿真重点实验室福建厦门361005 厦门路桥建设集团有限公司福建厦门361000

[目的]在桥面拓宽施工过程中,常出现新旧桥连接处纵向开裂、拓宽桥面横向开裂等典型问题,如何通过优化和改进桥面拓宽技术解决这些问题是桥梁工程的一个重要内容.[方法]以国内首座跨海大桥——厦门大桥的桥面拓宽工程为背景,提出了一种... 详细信息

[目的]在桥面拓宽施工过程中,常出现新旧桥连接处纵向开裂、拓宽桥面横向开裂等典型问题,如何通过优化和改进桥面拓宽技术解决这些问题是桥梁工程的一个重要内容.[方法]以国内首座跨海大桥——厦门大桥的桥面拓宽工程为背景,提出了一种加肋钢悬臂支撑-底部钢板组合的桥面拓宽方法.该方法有机结合了钢-混组合梁、正交异性钢悬臂板、底部加固钢板等桥面拓宽加固方法,采用混凝土现浇板作为桥面板、湿接法连接新旧桥梁,然后通过外延加肋钢悬臂构建支撑结构,并兼做现浇桥面混凝土的永久性模板.[结果]厦门大桥桥面拓宽加固工程的三维有限元仿真结果表明,钢悬臂布置间距增大会导致拓宽部分混凝土桥面板的拉应力增加,而设置下部加固钢板对于拓宽桥梁结构的挠度和应力分布影响明显.[结论]通过合理布置钢悬臂支撑结构和底部钢板,可显著减少拓宽部分混凝土纵横向裂缝的产生,改善拓宽后的桥梁的力学性能.相关成果有效支撑了厦门大桥的拓宽加固改造施工,为同类工程提供了有益的参考.

关键词：厦门大桥桥面拓宽加肋钢悬臂支撑底部加固钢板桥面裂缝

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深圳半岛城邦与成都天府长城10号地块

城市建筑 2007年第1期4卷 56-61页

作者： Aube Architecture Design(france.co.,Ltd 法国欧博建筑与城市规划设计公司深圳.518053

项目一、深圳半岛城邦一、基地概况基地位于深圳市南山区蛇口片区东侧，北靠蛇口山公园、东南面向深圳湾，隔海与香港的大屿山和元朗地区遥遥相望，西南面是开阔的南海，正西面是蛇口渔港码头。

关键词：深圳市南山区地块长城渔港码头蛇口深圳湾大屿山

East Asian monsoon intensification promoted weathering of the magnesium-rich southern China upper crust and its global significance

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Science China Earth Sciences 2021年第7期64卷 1155-1170页

作者： Yibo YANG Albert GALY Xiaomin FANG Christian france-LANORD Shiming WAN Rongsheng YANG Jian ZHANG Ran ZHANG Song YANG Yunfa MIAO Yudong LIU Chengcheng YE Key Laboratory of continental collision and Plateau Uplift Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101China Centre de Recherches Pétrographiques et Géochimiques UMR7358CNRS-Universitéde LorraineVandoeuvre les Nancy 54500France University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China Climate Change Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

The Oligocene-Miocene boundary Asian climatic reorganization linked to the northward migration of the East Asian monsoon into subtropical China is a potentially important but poorly constrained atmospheric co_(2) consumption ***,we performed a first-order estimate of the co_(2) consumption induced by silicate chemical weathering and organic carbon burial in subtropical China related to this climatic *** results show that an increase in long-term co_(2 )consumption by silicate weathering varies from 0.06×10^(12)to 0.87×10^(12)mol yr^(-1)depending on erosion flux reconstructions,with an~50%contribution of Mg-silicate weathering since the late *** organic carbon burial flux is approximately 25%of the contemporary co_(2) consumption by silicate *** results highlight the significant role of weathering of the Mg-rich upper continental crust in East China,which would contribute to the rapid decline in atmospheric co_(2) during the late Oligocene and the Neogene rise in the seawater Mg *** this climatic reorganization was mainly induced by the Tibetan Plateau uplift,our study suggests that the growth of the Himalayan-Tibetan Plateau can lead to indirect modification of the global carbon and magnesium cycles by changing the regional hydrological cycle in areas of East Asia that are tectonically less active.

关键词： Tibetan Plateau Late Oligocene Silicate weathering Carbon cycle Oceanic Mg cycle

Interleukin-6 role in head and neck squamous cell carcinoma progression

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2016年第2期2卷 -页

作者： Moaz M. Choudhary Thomas J. france Theodoros N. Teknos Pawan Kumar Department of 0tolaryngology-Head and Neck Surgery and comprehensive Cancer Center The 0hio State University Columbus 0H 43210 USA

Interleukin-6 (IL-6) is a pleiotropic cytokine which plays an important role in a num-ber of cellular processes including proliferation, survival, differentiation, migration and inva-sion. IL-6 mediates its downstream effects by activating a number of signaling cascades including JAK/STAT, PI3K/AKT and MAPK pathways. In addition to its effects on tumor cells, IL-6 also regulates tumor progression and tumor metastasis by modulating tumor angiogenesis and tumor lymphangiogenesis. A number of studies have shown that IL-6 levels are markedly upregulated in cancer patients. We and others have shown that high IL-6 expression indepen-dently predicts tumor recurrence, tumor metastasis and poor survival in head and neck cancer patients. Therefore targeting IL-6 signaling is a potential therapeutic strategy for the treat-ment of head and neck squamous cell carcinoma (HNSCC). In this review, we discuss the cur-rent understanding of the role of IL-6 in HNSCC progression and potential therapeutic strategies to target IL-6 signaling for the treatment of head and neck cancer patients. copyright a 2016 Chinese Medical Association. Production and hosting by Elsevier B.V. on behalf of KeAi communications co., Ltd. This is an open access article under the CC BY-NC-ND license (http://***/licenses/by-nc-nd/4.0/).

关键词： Head and neck squamous cell carcinoma Interleukin-6 JAK STAT3 MAPK PI3K/Akt Nanog

Juvenile ferric iron prevents microbiota dysbiosis and colitis in adult rodents

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World Journal of Gastroenterology 2012年第21期18卷 2619-2629页

作者： Chourouk Ettreiki Pascale Gadonna-Widehem Irène Mangin Mose coёffier Carine Delayre-Orthez Pauline M Anton Egeal Unit LaSalle Beauvais Polytechnic Institute60026 Beauvais France Biology Lab National Conservatory of Arts and Crafts75003 Paris France INSERM UMR 1073 School of Medicine Rouen University76183 Rouen France

AIM: To assess whether juvenile chronic ferric iron ingestion limit colitis and dysbiosis at adulthood in rats and mice. METHODS: Two sets of experiments were designed. In the first set, recently weaned mice were either orally administered ferrous (Fe2+) iron salt or ferric (Fe3+) microencapsulated iron for 6 wk. The last week of experiments trinitrobenzene sulfonic acid (TNBS) colitis was induced. In the second set, juvenile rats received the microencapsulated ferric iron for 6 wk and were also submitted to TNBS colitis during the last week of experiments. In both sets of experiments, animals were sacrificed 7 d after TNBS instillation. Severity of the inflammation was assessed by scoring macroscopic lesions and quantifying colonic myeloperoxidase (MPO) activity. Alteration of the microflora profile was estimated usingquantitative polymerase chain reaction (qPCR) by measuring the evolution of total caecal microflora, Bacteroidetes, Firmicutes and enterobacteria. RESULTS: Neither ferrous nor ferric iron daily exposures at the juvenile period result in any effect in control animals at adulthood although ferrous iron repeated administration in infancy limited weight gain. Ferrous iron was unable to limit the experimental colitis (1.71 ± 0.27 MPO U/mg proteinvs 2.47 ± 0.22 MPO U/mg protein in colitic mice). In contrast, ferric iron significantly prevented the increase of MPO activity (1.64 ± 0.14 MPO U/mg protein) in TNBS-induced colitis. Moreover, this positive effect was observed at both the doses of ferric iron used (75 and 150 mg/kg per day po - 6 wk). In the study we also compared, in both rats and mice, the consequences of chronic repeated low level exposure to ferric iron (75 mg/kg per day po - 6 wk) on TNBS-induced colitis and its related dysbiosis. We confirmed that ferric iron limited the TNBS-induced increase of MPO activity in both the rodent species. Furthermore, we assessed the ferric iron incidence on TNBS-induced intestinal microbiota dysbiosis. At firs

关键词： Chronic ferric iron supplementation Experimental colitis Microflora dysbiosis Rat Mice

Ammonia borane-based reactive mixture for trapping and converting carbon dioxide

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Frontiers of Materials Science 2022年第2期16卷 71-81页

作者： Carlos A.CASTILLA-MARTINEZ Bilge coŞKUNER FİLİZ Eddy PETIT Aysel KANTÜRK FİGEN Umit B.DEMIRCI Institut Europeen des Membranes(IEM) UMR 5635Univ MontpellierENSCMCNRSMontpellierFrance Department of Metallurgy and Materials Engineering Yildiz Technical UniversityİstanbulTurkey Department of Chemical Engineering Yildiz Technical UniversityİstanbulTurkey

Ammonia borane(NH_(3)BH_(3))is a reducing agent,able to trap and convert carbon *** the present work,we used a reactive solid consisting of a mixture of 90 wt.%of NH_(3)BH_(3)and 10 wt.%of palladium chloride,because the mixture reacts in a fast and exothermic way while releasing H2 and generating catalytic *** took advantage of such reactivity to trap and convert co_(2)(7 bar),knowing besides that Pd0 is a co_(2)hydrogenation *** operation(*** 1)was effective:BNH polymers,and B−O,C=O,C−O,and C−H bonds(like in BOCH_(3)and BOOCH groups)were *** then(in stage 2)pyrolyzed the as-obtained solid at 1250℃ and washed it with *** doing so,we isolated cyclotriboric acid H_(3)B3O6(stemming from B2O3 formed at 1250℃),hexagonal boron nitride,and graphitic *** conclusion,the stage 1 showed that co_(2)can be‘trapped’and converted,resulting in the formation of BOCH_(3)and BOOCH groups(possible sources of methanol and formic acid),and the stage 2 showed that co_(2)transforms into graphitic carbon.

关键词： ammonia borane boron nitride boron oxide carbon dioxide graphitic carbon

Subsolidus phase relations in the system MgO-ZnO-SiO_2 at high pressure

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Chinese Science Bulletin 1999年第12期44卷 1146-1149页

作者： LI Jianping, Jacques Kornprobst Didier Laporte Guangzhou Institute of Geochemistry , Chinese Academy of Sciences , Guangzhou 510640, China Departement des Sciences de la Terre, University Blasie Pascal, 630038 Clermont-Ferrand, france Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Département des sciences de la Terre Université Blasie Pascal Clermont-Ferrand France

The subsolidus phase relations were determined experimentally in the system MgO-ZnO-SiO2 at 1.0 GPa and 1 200℃, by use of the high-pressure apparatus "piston-cylinder". The results showed characteristics of the phases assemblage different from that in similar ternary systems. It is impossible to form complete Mg2SiO4-Zn2SiO4 olivine and Mg2Si2O6-Zn2Si2O6 pyroxene solid solution. This is controlled by the properties of Zn2+ with an outer layer of electron (Ar)3d10, different from others transition metal ions, like Fe2+ , Ni2+ , co2+ .

关键词： high pressure MgO-ZnO-SiO2 system subsolidus phase relation.

Effects of glutamine supplementation on gut barrier,glutathione content and acute phase response in malnourished rats during inflammatory shock

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World Journal of Gastroenterology 2007年第20期13卷 2833-2840页

作者： Liliana Belmonte Mose co■ffier Florence Le Pessot Olga Miralles-Barrachina Martine Hiron Antony Leplingard Jean-Franois Lemeland Bernadette Hecketsweiler Maryvonne Daveau Philippe Ducrotté Pierre Déchelotte Appareil Digestif Environnement Nutrition ADEN EA3234Institut Hospitalo-Universitaire de Recherche Biomédicale and Institut Fédératif de Recherches Multidisciplinaires sur les PeptidesFaculté de Médecine-PharmacieRouenFrance Service d’Anatomie Pathologique Centre Hospitalier UniversitaireRouenFrance INSERM unit 519 Institut Hospitalo-Universitaire de Recherche Biomédicale and Institut Fédératif de Recherches Multidisciplinaires sur les PeptidesFaculté de Médecine-PharmacieRouenFrance Groupe de Recherche sur les Antimicrobiens et les Microorganismes GRAM EA2656Institut Hospitalo-Universitaire de Recherche Biomédicale and Institut Fédératif de Recherches Multidisciplinaires sur les PeptidesFaculté de Médecine-PharmacieRouenFrance

AIM: To evaluate the effect of glutamine on intestinal mucosa integrity,glutathione stores and acute phase response in protein-depleted rats during an inflammatory shock. METHODS: Plasma acute phase proteins (APP),jejunal APP mRNA levels,liver and jejunal glutathione concentrations were measured before and one,three and seven days after turpentine injection in 4 groups of control,protein-restricted,protein-restricted rats supplemented with glutamine or protein powder. Bacterial translocation in mesenteric lymph nodes and intestinal morphology were also assessed. RESULTS: Protein deprivation and turpentine injection significantly reduced jejunal villus height,and crypt depths. Mucosal glutathione concentration significantly decreased in protein-restricted rats. Before turpentine oil,glutamine supplementation restored villus heights and glutathione concentration (3.24 ± 1.05 vs 1.72 ± 0.46 μmol/g tissue,P coprotein mRNA level after turpentine oil but did not affect its plasma concentration. Bacterial translocation in protein-restricted rats was not prevented by glutamine or protein powder supplementation. coNCLUSION: Glutamine restored gut glutathione stores and villus heights in malnourished rats but had no preventive effect on bacterial translocation in our model.

关键词： Acute phase response Glutamine Glutathione Intestine Malnutrition