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Effects of different atmospheres on the arc erosion behaviors of Ti_(3)SiC_(2)cathodes

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Science China(Technological Sciences) 2021年第3期64卷 620-628页

作者： ZHOU ZiJue FENG Yi ZHAO Hao QIAN Gang zhang JingCheng zhang xuebin HUANG XiaoChen School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China Instrumental Analysis Center Hefei University of TechnologyHefei 230009China School of Material and Chemical Engineering Bengbu UniversityBengbu 233030China

The effects of ambient atmospheres on the arc erosion behaviors of Ti_(3)SiC_(2)cathodes were investigated at 5.5 kV in argon,nitrogen,air,and *** mass loss of the cathodes increased in the order of argon,nitrogen,air,and oxygen and the morphologies were measured by 3D laser scanning confocal microscope with a gradual blooming *** spectroscopy,X-ray diffraction,and X-ray photoelectron spectroscopy were employed to detect the components of erosion *** erosion-chemical products mainly consisted of TiNx in nitrogen,TiN_(x),TiO_(2)and SiO_(2)in air,TiO_(2)and SiO_(2)in *** arc energy was responsible for the arc erosion characteristics in different atmospheres.

关键词： Ti_(3)SiC_(2) atmosphere arc erosion

Arc corrosion behavior of Cu-Ti_3AlC_2 composites in air atmosphere

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Science China(Technological Sciences) 2018年第4期61卷 551-557页

作者： HUANG XiaoChen FENG Yi QIAN Gang ZHAO Hao SONG ZhaoKun zhang JingCheng zhang xuebin School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China Instrumental Analysis Center Hefei University of TechnologyHefei 230009China

The arc corrosion evolution of Cu-20 vol.% Ti_3 AlC_2 cathodes is presented here. After eroded by 3, 4, 5, 6, 7, 8, 9, 10 kV DC voltage, respectively, the surface morphologies were characterized by field emission scanning electron microscope with craters and protrusions. Compared to small craters and dense protrusions of the morphology by high voltage, the eroded surface was covered with bigger craters and sparse protrusions at low voltage. No crack was discovered on the surface even at 10 kV. By means of energy dispersive spectroscopy and Raman spectroscopy, the decomposition of Cu-20 vol.% Ti_3 AlC_2 cathode to CuO,Al__2 O_3 and TiO_2 were proved. Meanwhile, W anode is oxidized to WO_2. The peak current increases with the increasing breakdown voltage, which is recorded by a digital memory oscilloscope.

关键词： Cu-Ti_3AlC_2 arc erosion FE-SEM Raman spectroscopy

Additional risk in extreme precipitation in China from 1.5℃to 2.0℃global warming levels

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Science Bulletin 2018年第4期63卷 228-234页

作者： Wei Li Zhihong Jiang xuebin zhang Laurent Li Ying Sun Key Laboratory of Meteorological Disaster of Ministry of Education Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisasterNanjing University of Information Science and TechnologyNanjing 210044China Joint International Research Laboratory of Climate and Environment Change.Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disaster Nanjing University of Information Science and Technology Nanjing 210044China Climate Research Division Environment and Climate Change CanadaTorontoOntario M3H 5T4Canada Laboratoire de Meteorologie Dynamique CNRSSorbonne UniversitesUPMC Universite Paris 06ParisFrance National Climate Center Laboratory for Climate StudiesChina Meteorological AdministrationBeifing 100812China

To avoid dangerous climate change impact, the Paris Agreement sets out two ambitious goals: to limit the global warming to be well below 2 ℃ and to pursue effort for the global warming to be below 1.5 ℃ above the pre-industrial level. As climate change risks may be region-dependent, changes in magnitude and probability of extreme precipitation over China are investigated under those two global warming levels based on simulations from the Coupled Model Inter-Comparison Projects Phase 5. The focus is on the added changes due to the additional half a degree warming from 1.5 ℃ to 2 ℃ . Results show that regional average changes in the magnitude do not depend on the return periods with a relative increase around 7% and 11% at the 1.5 ℃ and 2 ℃ global warming levels, respectively. The additional half a degree global warming adds an additional increase in the magnitude by nearly 4%. The regional average changes in term of occurrence probabilities show dependence on the return periods, with rarer events(longer return periods) having larger increase of risk. For the 100-year historical event, the probability is projected to increase by a factor of 1.6 and 2.4 at the 1.5 ℃ and 2 ℃ global warming levels, *** projected changes in extreme precipitation are independent of the RCP scenarios.

关键词： 1.5 ℃ and 2 ℃ global warmingExtreme precipitationChina

Understanding and building upon pioneering work of Nobel Prize in Physics 2021 laureates Syukuro Manabe and Klaus Hasselmann:From greenhouse effect to Earth system science and beyond

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Science China Earth Sciences 2022年第4期65卷 589-600页

作者： Tianjun ZHOU Wenxia zhang Deliang CHEN xuebin zhang Chao LI Meng ZUO Xiaolong CHEN State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Department of Earth Sciences University of GothenburgGothenburg 40530Sweden Environment and Climate Change Canada Toronto M3H 5T4Canada Max Planck Institute for Meteorology Hamburg 20146Germany

The Nobel Prize in Physics 2021 was awarded jointly to Syukuro Manabe,Klaus Hasselmann,and Giorgio Parisi for their groundbreaking contributions to our understanding of complex *** is the first time that climate scientists were awarded the Nobel Physics ***,we present the evolution of climate science in the past~200 years and highlight the landmarks of the developments in advancing our understanding of climate change,placing the pioneering contributions of Manabe and Hasselmann into a historical *** backbone of modern climate science is further discussed in the context of the development of the discipline from the discovery of the greenhouse effect to the formation of Earth system *** on the future development of climate science are also`presented.

关键词： Greenhouse gases Climate change General Circulation Model Detection and attribution Climate science Earth system science

The dynamic and thermodynamic processes dominating the reduction of global land monsoon precipitation driven by anthropogenic aerosols emission

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Science China Earth Sciences 2020年第7期63卷 919-933页

作者： Tianjun ZHOU Wenxia zhang Lixia zhang xuebin zhang Yun QIAN Dongdong PENG Shuangmei MA Buwen DONG State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China CAS Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Environment and Climate Change Canada 4905 Dufferin StreetTorontoONCanada Atmospheric Science and Global Change Division Pacific Northwest National LaboratoryRichlandWashington 99352USA Institute of Tropical and Marine Meteorology China Meteorological AdministrationGuangzhou 510640China National Centre for Atmospheric Science Department of MeteorologyUniversity of ReadingReading RG66BBUK

Changes in monsoon precipitation have profound social and economic impacts as more than two-thirds of the world’s population lives in monsoon *** show a significant reduction in global land monsoon precipitation during the second half of the 20 th *** the cause of this change,especially possible anthropogenic origins,is ***,we compare observed changes in global land monsoon precipitation during 1948–2005 with those simulated by 5 global climate models participating in the Coupled Model Inter-comparison Project-phase 5(CMIP5)under different external *** show that the observed drying trend is consistent with the model simulated response to anthropogenic forcing and to anthropogenic aerosol forcing in *** apply the optimal fingerprinting method to quantify anthropogenic influences on precipitation and find that anthropogenic aerosols may have contributed to 102%(62–144%for the 5–95%confidence interval)of the observed decrease in global land monsoon precipitation.A moisture budget analysis indicates that the reduction in precipitation results from reduced vertical moisture advection in response to aerosol *** much of the monsoon regions,such as India and China,have been experiencing rapid developments with increasing aerosol emissions in the past decedes,our results imply a further reduction in monsoon precipitation in these regions in the future if effective mitigations to reduce aerosol emissions are not *** observed decline of aerosol emission in China since 2006 helps to alleviate the reducing trend of monsoon precipiptaion.

关键词： Global monsoon Detection Attribution Aerosol forcing Dynamic and thermodynamic processes

Understanding human influence on climate change in China

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National Science Review 2022年第3期9卷 128-143页

作者： Ying Sun xuebin zhang Yihui Ding Deliang Chen Dahe Qin Panmao Zhai National Climate Center Laboratory for Climate Studies Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science &Technology Climate Research Division Environment and Climate Change Canada Department of Earth Sciences University of Gothenburg China Meteorological Administration State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences

China’s climate has been warming since the 1950s, with surface air temperature increasing at a rate higher than the global average. Changes in climate have exerted substantial impacts on water resources,agriculture, ecosystems and human health. Attributing past changes to causes provides a scientific foundation for national and international climate policies. Here, we review recent progress in attributing the observed climate changes over past decades in China. Anthropogenic forcings, dominated by greenhouse gas emissions, are the main drivers for observed increases in mean and extreme temperatures. Evidence of the effect of anthropogenic forcings on precipitation is emerging. Human influence has increased the probability of extreme heat events, and has likely changed the occurrence probabilities for some heavy precipitation events. The way a specific attribution question is posed and the conditions under which the question is addressed present persistent challenges for appropriately communicating attribution results to non-specialists.

关键词： human influence detection and attribution climate change climate extremes

Formation and kinetics of porous cordierite from fly ash

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Chinese Journal Of Geochemistry 2008年第4期27卷 395-400页

作者： zhang xuebin WU Zuosheng MENG Guangyao LIU Xingqin School of Materials Science and Engineering Hefei University of Technology Hefei 230009 China Hefei Founding ＆ Forging Factory Anhui Hell Forklift Company Hefei 230026 China Department of Materials Science andEngineering University of Science and Technology of China Hefei 230026 China

Porous cordierite ceramics were prepared from a mixture of coal fly ash and basic magnesium carbonate at 1100-1350℃. Porosity,flexural strength and thermal expansion coefficient of the samples sintered at 1300℃ were estimated to be 26%,65 MPa and 4.21×10-6/ ℃ ,respectively. The kinetics of the formation progress was investigated by stepwise isothermal dilatometry (SID) accompanied with XRD,SEM and porosity measurement. It was found that the isothermal shrinkage data from SID could be well analyzed to get kinetic parameters according to the em-pirical rate equation developed by Makipirtti-Meng,dY/dt=nk(T)Y(1-Y)(Y/1-Y)1/n,where Y is the fractional shrinkage during the sintering process and n is a dimensionless component. The apparent activation energy △E values for 900-1000℃ and 1050-1150℃ were 1294 and 1778 kJ/mol,respectively.

关键词：堇青石灰分梯度等温线膨胀测量术 SID

Characteristics of stress distribution in floor strata and control of roadway stability under coal pillars

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Mining Science and Technology 2011年第2期21卷 243-247页

作者： Tongqiang Xiao Bai Jianbiao Xu Lei zhang xuebin State Key Laboratory of Coal Resources and Safe Mining China University of Mining ＆ Technology Xuzhou 221008 China School of Mines China University of Mining ＆ Technology Xuzhou 221008 China Coal Industry Jinan Design Institute Ltd. Jinan 250031 China

Given the difficulties encountered in roadway support under coal pillars,we studied the characteristics of stress distribution and their effect on roadway stability,using theoretical analysis and numerical *** results show that,under a coal pillar,vertical stress in a floor stratum increases while horizontal stress *** conclude that the increased difference between vertical and horizontal stress is an important reason for deformation of the surrounding rock and failures of roadways under coal *** on this,we propose control technologies of the surrounding rock of a roadway under a coal pillar,such as high strength and high pre-stressed bolt support,cable reinforcement support single hydraulic prop with beam support and reinforcement by grouting of the surrounding rock,which have been successfully applied in a stability control project of a roadway under a coal pillar.

关键词： Close-distance seams Coal pillar Stress distribution Roadway layout Surrounding rock control

Role of anthropogenic forcing and atmospheric circulation in a lowtemperature event in February 2022 in eastern China

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Advances in Climate Change Research 2023年第6期14卷 921-929页

作者： Zhi-Fan CHEN Ying SUN xuebin zhang Tim LI Jin-Hua YU Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environment Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science and TechnologyNanjing 210044China Climate Studies Key Laboratory National Climate CenterChina Meteorological AdministrationBeijing 10008lChina Climate Research Division Environment and Climate Change CanadaToronto M3H 5T4Canada Department of Atmospheric Sciences University of Hawai at ManoaHonolulu HI 96822USA

In February 2022,eastern China experienced prolonged low temperatures,with significant impacts on agriculture,transportation,and power *** regional average temperature anomaly for February 2022 was-0.65℃,making it the third coldest February from 2000 to *** the influence of anthropogenic forcing and atmospheric circulation on low-temperature events is important for climate change adaptation and mitigation in the *** study used observational and model data from the Coupled Model Intercomparison Project Phase 6 to conduct an extreme event attribution *** results showed that anthropogenic forcing led to a 1.5-fold decrease in the probability of 2022-like events,with anthropogenic greenhouse gases being the primary contributors to this ***,aerosols slightly increased the likelihood of such *** evaluate the role of atmospheric circulation in this event,we chose Siberian High as the key circulation system and employed circulation similarity,intensity classification,and regression methods to estimate the impacts of circulation patterns,circulation in-tensity,and human-induced circulation *** results demonstrated that under the influence of the same anthropogenic forcing,the presence of an anomalous Siberian High and anomalously enhanced intensity of the Siberian High both increased the likelihood of such a cold event ***,anthropogenic forcing exerts a negligible effect on such cold events via anomalous circulation.

关键词： Low-temperature event Attribution Intensity of the Siberian high Anthropogenic forcing Atmospheric circulation