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Neural Regeneration Research 2024年第5期19卷 984-987页

作者： Erxi Wu Dan Qi Damir Nizamutdinov Jason h.huang Department of Neurosurgery and Neuroscience Institute Baylor Scott&White HealthTempleTXUSA Texas A&M University School of Medicine TempleTXUSA Texas A&M University School of Pharmacy College StationTXUSA LIVESTRONG Cancer Institutes and Department of Oncology Dell Medical Schoolthe University of Texas at AustinAustinTXUSA Department of Neurosurgery Baylor College of MedicineTempleTXUSA

Neuron-astrocyte interactions are vital for the brain’s *** astrocyte activities is crucial for comprehending the complex neural network,particularly the population-level functions of neurons in different cortical states and associated behaviors in *** on animal sleep and wakefulness have revealed distinct cortical synchrony patterns between ***,outnumbering neurons by nearly fivefold,support and regulate neuronal and synaptic *** research on astrocyte activation during cortical state transitions has emphasized the influence of norepinephrine as a neurotransmitter and calcium waves as key components of ion channel *** summary focuses on a few recent studies investigating astrocyte-neuron interactions in mouse models during sleep,wakefulness,and arousal levels,exploring the involvement of noradrenaline signaling,ion channels,and glutamatergic signaling in different cortical *** findings highlight the significant impact of astrocytes on large-scale neuronal networks,influencing brain activity and *** astrocytic signaling pathways shows promise for treating sleep disorders and arousal *** research is needed to understand astrocytic calcium signaling in different brain regions and its implications for dysregulated brain states,requiring future human studies to comprehensively investigate neuron-astrocyte interactions and pave the way for therapeutic interventions in sleep-and arousal-related disorders.

关键词： arousal astrocyte calcium waves locus coeruleus neuron-astrocyte interaction norepinephrine sleep wakefulness

Decorating crystalline YFe_(2-x)Al_(x) on the Mg_(60)La_(10)Ni_(20)Cu_(10) amorphous alloy as “hydrogen pump” to realize fast de/hydrogenation

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Journal of Materials Science & Technology 2024年第6期173卷 72-79页

作者： L.J.huang h.Wang L.Z.Ouyang M.Zhu h.J.Lin School of Materials Science and Engineering Key Laboratory of Advanced Energy Storage Materials of Guangdong ProvinceSouth China University of TechnologyGuangzhou 510641China Institute of Advanced Wear&Corrosion Resistance and Functional Materials Jinan UniversityGuangzhou 510632China

Mg-based amorphous alloys are one of the potential hydrogen storage materials but suffer from sluggish dehydrogenation/hydrogenation(de/hydrogenation)*** this work,as a new strategy,a hydrogen pump is built on the surface of amorphous alloys to solve this *** milling crystalline YFe_(2-x)Al_(x) hydrogen storage alloy with Mg_(60)La_(10)Ni_(20)Cu_(10) amorphous alloy,fine crystalline particles were seeded on amorphous alloy powder to form a“strawberry”*** to the TEM observation,a metallurgical bonding boundary formed between the Mg-based amorphous matrix and the Y-Fe-Al crystalline *** microstructure and de/hydrogenation kinetics investigation,the“hydrogen pump”effect of the seeded crystalline alloy was confirmed,which makes it much easier for the hydrogen to dissociate on and diffuse through the surface of the Mg-based amorphous *** such effect,the h absorption rate of Mg_(60)La_(10)Ni_(20)Cu_(10) amorphous alloy became almost eight times faster and it absorbs ~2.8 wt.% in 1 h at 130℃ under 4.5 MPa-h_(2).Further,fast hydrogenation can even achieve at 70℃ and the low-temperature dehydrogenation kinetics of the amorphous hydride can be also greatly *** present work proves that surface modification is of great importance for obtaining Mg-based amorphous alloy with ideal hydrogen storage performance.

关键词： hydrogen storage Mg-based amorphous alloy hydrogen pump Composite structure

A thermodynamic perspective on electrode poisoning in solid oxide fuel cells

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1449-1455页

作者： Kevin huang Department of Mechanical Engineering University of South CarolinaColumbiaUSA

A critical challenge to the commercialization of clean and high-efficiency solid oxide fuel cell(SOFC)technology is the insuf-ficient stack lifespan caused by a variety of degradation mechanisms,which are associated with cell components and chemical *** components related degradation refers to thermal/chemical/electrochemical deterioration of cell materials under operating conditions,whereas the latter regards impurities in feedstocks of oxidant(air)and reductant(fuel).This article provides a thermodynamic perspective on the understanding of the impurities-induced degradation mechanisms in *** discussion focuses on using thermodynamic ana-lysis to elucidate poisoning mechanisms in cathodes by impurity species such as Cr,CO_(2),h_(2)O,and SO_(2) and in the anode by species such as S(or h_(2)S),SiO_(2),and P_(2)(or Ph_(3)).The author hopes the presented fundamental insights can provide a theoretical foundation for search-ing for better technical solutions to address the critical degradation challenges.

关键词： impurities air fuel reaction activity

Search for electron-antineutrinos associated with gravitational-wave events GW150914,GW151012,GW151226,GW170104,GW170608,GW170814,and GW170817 at Daya Bay

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Chinese Physics C 2021年第5期45卷 190-201页

作者： F.P.An A.B.Balantekin h.R.Band M.Bishai S.Blyth G.F.Cao J.Cao J.F.Chang Y.Chang h.S.Chen S.M.Chen Y.Chen Y.x.Chen J.Cheng Z.K.Cheng J.J.Cherwinka M.C.Chu J.P.Cummings O.Dalager F.S.Deng Y.Y.Ding M.V.Diwan T.Dohnal J.Dove M.Dvorak D.A.Dwyer J.P.Gallo M.Gonchar G.h.Gong h.Gong W.Q.Gu J.Y.Guo L.Guo x.h.Guo Y.h.Guo Z.Guo R.W.hackenburg S.hans M.he K.M.heeger Y.K.heng A.higuera Y.K.hor Y.B.hsiung B.Z.hu J.R.hu T.hu Z.J.hu h.x.huang x.T.huang Y.B.huang P.huber D.E.Jaffe K.L.Jen x.L.Ji x.P.Ji R.A.Johnson D.Jones L.Kang S.h.Kettell S.Kohn M.Kramer T.J.Langford J.Lee J.h.C.Lee R.T.Lei R.Leitner J.K.C.Leung F.Li J.J.Li Q.J.Li S.Li S.C.Li W.D.Li x.N.Li x.Q.Li Y.F.Li Z.B.Li h.Liang C.J.Lin G.L.Lin S.Lin J.J.Ling J.M.Link L.Littenberg B.R.Littlejohn J.C.Liu J.L.Liu C.Lu h.Q.Lu J.S.Lu K.B.Luk x.B.Ma x.Y.Ma Y.Q.Ma C.Marshall D.A.Martinez Caicedo K.T.MeDonald R.D.McKeown Y.Meng J.Napolitano D.Naumov E.Naumova J.P.Ochoa-Ricoux A.OIshevskiy h.-R.Pan J.Park S.Patton J.C.Peng C.S.J.Pun F.Z.Qi M.Qi x.Qian N.Raper J.Ren C.Morales Reveco R.Rosero B.Roskovec x.C.Ruan h.Steiner J.L.Sun T.Tmej K.Treskov W.-h.Tse C.E.Tull B.Viren V.Vorobel C.h.Wang J.Wang M.Wang N.Y.Wang R.G.Wang W.Wang W.Wang x.Wang Y.Wang Y.F.Wang Z.Wang Z.Wang Z.M.Wang h.Y.Wei L.h.Wei L.J.Wen K.Whisnant C.G.White h.L.h.Wong E.Worcester D.R.Wu F.L.Wu Q.Wu W.J.Wu D.M.xia Z.Q.xie Z.Z.xing J.L.xu T.xu T.xue C.G.Yang L.Yang Y.Z.Yang h.F.Yao M.Ye M.Yeh B.L.Young h.Z.Yu Z.Y.Yu B.B.Yue S.Zeng Y.Zeng L.Zhan C.Zhang F.Y.Zhang h.h.Zhang J.W.Zhang Q.M.Zhang x.T.Zhang Y.M.Zhang Y.x.Zhang Y.Y.Zhang Z.J.Zhang Z.P.Zhang Z.Y.Zhang J.Zhao L.Zhou h.L.Zhuang J.h.Zou Instiute of Modern Physics East China University of Science and TechnologyShanghai 200237 University of Wisconsin MadisonWisconsin 53706 Wright Laboratory and Department of Physics Yale UniversityNew HavenConnecticut 06520 Brookhaven National Laboratory UptonNew York 11973 Department of Physics National Taiwan UniversityTaipei Institute of high Energy Physics Beijing 100049 National United University Miao-Li Department of Engineering Physics Tsinghua UniversityBejing 100084 Shenzhen University Shenzhen 518060 Sun Yat-Sen(Zhongshan)University Guangzhou North China Electric Power University Bejjing 102206 Chinese University of hong Kong Hong Kong 999077 Siena College LoudonvilleNew York 12211 Department of Physics and Astronomy University of CaliforniaIrvineCaliformia 92697 University of Science and Technology of China Hefei 230026 Charles University Faculty of Mathematics and PhysicsPrague Department of Physics University of llinois at Urbana-ChampaignUrbanaIlinois 61801 Lawrence Berkeley National Laboratory BerkeleyCalifornia 94720 Department of Physics Illinois Institute of TechnologyChicagoIllinois 60616 Joint Institute for Nuclear Research DubnaMoscow Region Beijing Normal University Beijing 100875 Department of Nuclear Science and Technology School of Energy and Power EngineeringXi'an Jiaotong UniversityXi'an 710049 Department of Physics University of HoustonHoustonTexas 77204 China Institute of Atomic Energy Beijing 102413 Shandong University Jinan 250100 Guangxi University Nanning 530004 Center for Neutrino Physics Virginia TechBlacksburgVirginia 24061 Institute of Physics National Chiao-Tung UniversityHsinchu Department of Physics University of CincinnatiCincinnatiOhio 45221 Department of Physies Collge of Science and TechnologyTemple UniversityPhiladelphiaPennsylvania 19122 Dongguan University of Technology Dongguan 523808 Department of Physics University of CaliforniaBerkeleyCalifornia 94720 Department of Physics The University of Hong KongPokfulamHong Kong 999077 School

The establishment of a possible connection between neutrino emission and gravitational-wave(GW)bursts is important to our understanding of the physical processes that occur when black holes or neutron stars *** the Daya Bay experiment,using the data collected from December 2011 to August 2017,a search was per-formed for electron-antineutrino signals that coincided with detected GW events,including GW150914,GW151012,GW151226,GW170104,GW170608,GW 170814,and GW *** used three time windows of±10,±500,and±1000 s relative to the occurrence of the GW events and a neutrino energy range of 1.8 to 100 MeV to search for correlated neutrino *** detected electron-antineutrino candidates were consistent with the expected background rates for all the three time *** monochromatic spectra,we found upper limits(90%confidence level)of the electron-antineutrino fluence of(1.13-2.44)×10^(11)cm^(-2)at 5 MeV to 8.0×10^(7)cm^(-2)at 100 MeV for the three time w *** the assumption of a Fermi-Dirac spectrum,the upper limits were found to be(5.4-7.0)×10^(9)cm^(2)for the three time windows.

关键词： grav itational waves electron-antineutrinos fluence upper limit

The Rising Burden of hepatocellular Carcinoma: Is the Gender Gap Narrowing?

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Journal of Clinical and Translational hepatology 2024年第9期12卷 763-764页

作者： James K.h.ho Prem h.Thurairajah Daniel Q.huang Kristie h.Fan Division of Gastroenterology and hepatology National University HospitalNational University Health SystemSingaporeSingapore

Dear Editors,The landscape of hepatocellular carcinoma(hCC)is continuously *** global trends indicate a significant shift in the epidemiology of hCC from viral-related to non-viral-related ***-associated fatty liver disease has emerged as the fastest-growing contributor to hCC in recent years,due to the increased prevalence of obesity and metabolic risk factors.

关键词： Carcinoma epidemiology obesity

STCF conceptual design report (Volume 1): Physics & detector

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Frontiers of physics 2024年第1期19卷 1-154页

作者： M.Achasov x.C.Ai L.P.An R.Aliberti Q.An x.Z.Bai Y.Bai O.Bakina A.Barnyakov V.Blinov V.Bobrovnikov D.Bodrov A.Bogomyagkov A.Bondar I.Boyko Z.h.Bu F.M.Cai h.Cai J.J.Cao Q.h.Cao x.Cao Z.Cao Q.Chang K.T.Chao D.Y.Chen h.Chen h.x.Chen J.F.Chen K.Chen L.L.Chen P.Chen S.L.Chen S.M.Chen S.Chen S.P.Chen W.Chen x.Chen x.F.Chen x.R.Chen Y.Chen Y.Q.Chen h.Y.Cheng J.Cheng S.Cheng T.G.Cheng J.P.Dai L.Y.Dai x.C.Dai D.Dedovich A.Denig I.Denisenko J.M.Dias D.Z.Ding L.Y.Dong W.h.Dong V.Druzhinin D.S.Du Y.J.Du Z.G.Du L.M.Duan D.Epifanov Y.L.Fan S.S.Fang Z.J.Fang G.Fedotovich C.Q.Feng x.Feng Y.T.Feng J.L.Fu J.Gao Y.N.Gao P.S.Ge C.Q.Geng L.S.Geng A.Gilman L.Gong T.Gong B.Gou W.Gradl J.L.Gu A.Guevara L.C.Gui A.Q.Guo F.K.Guo J.C.Guo J.Guo Y.P.Guo Z.h.Guo A.Guskov K.L.han L.han M.han x.Q.hao J.B.he S.Q.he x.G.he Y.L.he Z.B.he Z.x.heng B.L.hou T.J.hou Y.R.hou C.Y.hu h.M.hu K.hu R.J.hu W.h.hu x.h.hu Y.C.hu J.hua G.S.huang J.S.huang M.huang Q.Y.huang W.Q.huang x.T.huang x.J.huang Y.B.huang Y.S.huang N.hüsken V.Ivanov Q.P.Ji J.J.Jia S.Jia Z.K.Jia h.B.Jiang J.Jiang S.Z.Jiang J.B.Jiao Z.Jiao h.J.Jing x.L.Kang x.S.Kang B.C.Ke M.Kenzie A.Khoukaz I.Koop E.Kravchenko A.Kuzmin Y.Lei E.Levichev C.h.Li C.Li D.Y.Li F.Li G.Li G.Li h.B.Li h.Li h.N.Li h.J.Li h.L.Li J.M.Li J.Li L.Li L.Li L.Y.Li N.Li P.R.Li R.h.Li S.Li T.Li W.J.Li x.Li x.h.Li x.Q.Li x.h.Li Y.Li Y.Y.Li Z.J.Li h.Liang J.h.Liang Y.T.Liang G.R.Liao L.Z.Liao Y.Liao C.x.Lin D.x.Lin x.S.Lin B.J.Liu C.W.Liu D.Liu F.Liu G.M.Liu h.B.Liu J.Liu J.J.Liu J.B.Liu K.Liu K.Y.Liu K.Liu L.Liu Q.Liu S.B.Liu T.Liu x.Liu Y.W.Liu Y.Liu Y.L.Liu Z.Q.Liu Z.Y.Liu Z.W.Liu I.Logashenko Y.Long C.G.Lu J.x.Lu N.Lu Q.F.Lü Y.Lu Y.Lu Z.Lu P.Lukin F.J.Luo T.Luo x.F.Luo Y.h.Luo h.J.Lyu x.R.Lyu J.P.Ma P.Ma Y.Ma Y.M.Ma F.Maas S.Malde D.Matvienko Z.x.Meng R.Mitchell A.Nefediev Y.Nefedov S.L.Olsen Q.Ouyang P.Pakhlov G.Pakhlova x.Pan Y.Pan E.Passemar Y.P.Pei h.P.Peng L.Peng x.Y.Peng x.J.Peng K.Peters S.Pivovarov E.Pyata B.B.Qi Y.Q.Qi W.B.Qian Y.Qian C.F.Qiao J.J.Qin J.J.Qin L.Q.Qin x.S.Qin T.L.Qiu J.Rademacker C.F.Redmer h.Y.Sang Anhui University Hefei 230039China Beihang University Beijing 100191China Budker Institute of Nuclear Physics Novosibirsk 630090Russia CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China Cavendish Laboratory University of CambridgeJJ Thomson AveCambridge CB30HEUnited Kingdom Central China Normal University Wuhan 430079China Central South University Changsha 410083China China University of Geosciences Wuhan 430074China China University of Mining and Technology Xuzhou 221116China École Polytechnique Fédérale de Lausanne(EPFL) LausanneSwitzerland Fudan University Shanghai 200433China Goethe University Frankfurt D-60325 Frankfurt am MainGermany Guangxi Normal University Guilin 541004China Guangxi Uninversity Nanning 530004China hangzhou Institute for Advanced Study UCASHangzhou 310024China hebei Normal University Shijiazhuang 050024China hebei University Baoding 071002China hefei University of Technology Hefei 230601China helmholtz Institute Mainz Staudinger Weg 18D-55099 MainzGermany henan Normal University Xinxiang 453007China henan University Kaifeng 475004China high Energy Physics Center Chung-Ang UniversitySeoul 06974Korea higher School of Economy 11 Pokrovsky Bulvar Moscow 109028Russia huangshan University Huangshan 245000China hubei University of Automotive Technology Shiyan 442002China hunan Normal University Changsha 410081China hunan University of Science and Technology Xiangtan 411201China hunan University Changsha 410082China Indiana University BloomingtonIndiana 47405USA Inner Mongolia University Hohhot 010021China Institute of Advanced Science Facilities Shenzhen 518107China Institute of high Energy Physics Chinese Academy of SciencesBeijing 100049China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Institute of Physics Academia SinicaTaipeiTaiwan 11529China Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100190China Jilin University Changch

The superτ-charm facility(STCF)is an electron–positron collider proposed by the Chinese particle physics *** is designed to operate in a center-of-mass energy range from 2 to 7 GeV with a peak luminosity of 0.5×10^(35) cm^(–2)·s^(–1) or *** STCF will produce a data sample about a factor of 100 larger than that of the presentτ-charm factory—the BEPCII,providing a unique platform for exploring the asymmetry of matter-antimatter(charge-parity violation),in-depth studies of the internal structure of hadrons and the nature of non-perturbative strong interactions,as well as searching for exotic hadrons and physics beyond the Standard *** STCF project in China is under development with an extensive R&D *** document presents the physics opportunities at the STCF,describes conceptual designs of the STCF detector system,and discusses future plans for detector R&D and physics case studies.

关键词： electron–positron collider tau-charm region high luminosity STCF detector conceptual design

Laminar Flame Structure-Dependent Exergy Destruction Behavior at Auto-Ignition Time Scale:A Case Study of Dimethyl Ether(DME)

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Journal of Thermal Science 2024年第4期33卷 1257-1271页

作者： WU honghuan huang Wenlin ZhAO hao SUN Wuchuan huang Zuohua ZhANG Yingjia State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an710049China

hybrid deflagration/auto-ignition flame structures coexist in the combustion of advanced *** exergy destruction caused by different irreversible processes under varied flame regimes is thus important for understanding engine *** this study,the flame propagation modes for the premixed DME/air mixtures are numerically investigated under engine-relevant *** entropy generation and exergy destruction characteristics are compared under different flame *** reveal that as the typical premixed flame transition towards auto-ignition front,the exergy destruction from heat conduction and species mass diffusion gradually vanish and are dominated by chemical *** distributions of temperature and species mole fraction in the flame domain are analyzed to clarify the exergy destruction behaviors caused by heat conduction and mass ***,by dividing the DME oxidation process into four stages,the main reaction channels that contribute to the increase in exergy destruction from chemical reaction have been *** is found that the production and consumption of Ch_(2)O and hO_(2) radical dominate the exergy destruction behavior during DME *** this basis,the kinetic mechanism of low-temperature chemistry causing greater exergy destruction is ***,low-temperature chemistry leads to significant exergy destruction due to(a)the large irreversibility of itself and(b)(mainly)the enhancement of h_(2)O_(2)loop reactions by low-temperature reaction *** the reduction of combustion irreversibility is promising to be achieved by reasonably regulating the fuel oxidation path.

关键词： exergy destruction flame structures entropy generation low-temperature chemistry DME

Associations of daily sedentary behavior,physical activity,and sleep with irritable bowel syndrome:A prospective analysis of 362,193 participants

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Journal of Sport and health Science 2024年第1期13卷 72-80页

作者： xu Gao Sifan Tian Ninghao huang Gang Sun Tao huang Department of Occupational and Environmental health Sciences School of Public HealthPeking UniversityBeijing 100191China Department of Epidemiology and Biostatistics School of Public HealthPeking UniversityBeijing 100191China Department of Gastroenterology and hepatology First Medical Center of People's Liberation Army General HospitalBeijing 100853China

Background:Irritable bowel syndrome(IBS)substantially affects quality of life and requires early *** study aimed to elucidate the relationships between IBS and daily behaviors,including sedentary behavior(SB),physical activity(PA),and *** particular,it seeks to identify healthy behaviors to reduce IBS risk,which previous studies have rarely ***:Daily behaviors were retrieved from self-reported data of 362,193 eligible UK Biobank *** cases were determined by self-report or health care data according to RomeⅣ***:A total of 345,388 participants were IBS-free at baseline,during a median follow-up of 8.45 years,19,885 incident IBS cases were *** examined individually,SB and shorter(≤7 h/day)or longer(>7 h/day)sleep duration were each positively associated with increased IBS risk,and PA was associated with lower IBS *** isotemporal substitution model suggested that replacing SB with other activities could provide further protective effects against IBS *** people sleeping≤7 h/day,replacing 1 h of SB with equivalent light PA,vigorous PA,or sleep was associated with 8.1%(95%confidence interval(95%CI):0.901-0.937),5.8%(95%CI:0.896-0.991),and 9.2%(95%CI:0.885-0.932)reduced IBS risk,*** people sleeping>7 h/day,light and vigorous PA were associated with a 4.8%(95%CI:0.926-0.978)and a 12.0%(95%CI:0.815-0.949)lower IBS risk,*** benefits were mostly independent of genetic risk for ***:SB and unhealthy sleep duration are risk factors for IBS.A promising way to mitigate IBS risk for individuals sleeping≤7 h/day and for those sleeping>7 h/day appears to be by replacing SB with adequate sleep or vigorous PA,respectively,regardless of the genetic predisposition of IBS.

关键词： Irritable bowel syndrome Isotemporal substitution model Physical activity Sedentary behavior Sleep

Access to high-Molecular-Weight Polyethylenes through high Temperature Ethylene Polymerization Catalysed by Ethylene-Bridged ansa-(3-R-Cyclopentadienyl)(Fluorenyl) Zirconocene Complexes

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Chinese Journal of Polymer Science 2024年第1期42卷 42-51,I0007页

作者： Bo Li haiyan Ma Jiling huang Shanghai Key Laboratory of Functional Materials Chemistry and Laboratory of Organometallic Chemistry School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

A series of C1-symmetric ethylene-bridged ansa-(3-R-cyclopentadienyl)(fluorenyl) metallocene complexes(Zr: 1-5;hf: 6) have been synthesized, characterized and investigated as catalyst precursors for the high temperature ethylene polymerization. Using methylaluminoxane(MAO) as the cocatalyst, zirconium complexes 1-5 bearing a bulky substituent on the 3-position of the cyclopendienyl ring showed high catalytic activities up to 1.48×10^(7) g PE·mol_(Zr)^(-1)·h^(-1) toward the polymerization of ethylene and afforded polyethylenes with high molecular weights(1.49×10^(5)-6.31×10^(5) g/mol), meanwhile exhibting great thermal stability at high temperatures up to 120 ℃ together with a long catalytic life time up to 2 h. By adopting low Al/Zr ratios, such as 125, polyethylenes with ultra high molecular weights up to 2.86×106 g/mol were obtained. It is worthy of noting that zirconium complexes 1-4 bearing a substituent with an aryl pendant showed temperature-dependent activities, which increased rapidly with the increase of polymerization temperature, thus weak interaction of the pendent aryl group with the cationic active center is proposed to account for the very low activities displayed at low temperatures. In contrast to zirconocene complexes 1-5, hafnocene complex 6 only displayed very low catalytic activities toward the polymerization of ethylene and afforded polyethylenes with molecular weights ten times smaller than those obtained by zirconocene complexes 1-5. Zirconocene complexes 1-5 were also able to catalyse the polymerization of propylene at high temperatures, but only afforded waxes with low molecular weights.

关键词： ansa-Metallocene Ethylene Propylene Polymerization high temperature