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Tuning the crystalline and electronic structure of ZrO_(2)via oxygen vacancies and nano-structuring for polysulfides conversion in lithium-sulfur batteries

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Journal of Energy Chemistry 2024年第1期88卷 82-93,I0003页

作者： Shengnan Fu Chaowei Hu Jing Li Hongtao Cui Yuanyuan Liu Kaihua Liu yanzhao yang Meiri Wang Shandong Key Laboratory for Chemical Engineering and Processing School of Chemistry&Chemical EngineeringYantai UniversityYantai 264000ShandongChina Key Laboratory for Special Functional Aggregate Materials of Education Ministry School of Chemistry and Chemical EngineeringShandong UniversityJinan 250100ShandongChina

The recent emergence of tetragonal phases zirconium dioxide(ZrO_(2))with vacancies has generated significant interest as a highly efficient and stable electrocatalyst with potential applications in trapping polysulfides and facilitating rapid conversion in lithium-sulfur batteries(LSBs).However,the reduction of ZrO_(2)is challenging,even under strong reducing atmospheres at high temperatures and ***,the limited presence of oxygen vacancies results in insufficient active sites and reaction interfaces,thereby hindering practical ***,we successfully introduced abundant oxygen vacancies into ZrO_(2)at the nanoscale with the help of carbon nanotubes(CNTs-OH)through hydrogen-etching at lower temperatures and *** introduced oxygen vacancies on ZrO_(2-x)/CNTs-OH can effectively rearrange charge distribution,enhance sulfiphilicity and increase active sites,contributing to high ionic and electronic transfer kinetics,strong binding energy and low redox barriers between polysulfides and ZrO_(2-x).These findings have been experimentally validated and supported by theory *** a result,LSBs assembled with the ZrO_(2-x)/CNTs-OH modified separators demonstrate excellent rate performance,superior cycling stability,and ultra-high sulfur ***,at high sulfur loading of 6 mg cm^(-2),the area capacity is still up to 6.3 mA h cm^(-2).This work provides valuable insights into the structural and functional optimization of electrocatalysts for batteries.

关键词： Lithium-sulfur batteries Oxygen vacancies Zirconium dioxide/carbon nanotubes with–OH Improved redox kinetics Superior cycling stability

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Effects of Bending-torsional Duct-induced Swirl Distortion on Aerodynamic Performance of a Centrifugal Compressor

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Journal of Thermal Science 2017年第2期26卷 97-106页

作者： HOU Hongjuan WANG Leilei WANG Rui yang yanzhao College of Mechanical and Equipment Engineering Hebei University of Engineering Kangyue Technology Co. Ltd

A turbocharger compressor working in commercial vehicles, especially in some passenger cars, often works together with some pipes with complicated geometry as an air intake system, due to limit of available space in internal combustion engine compartments. These pipes may generate various distortions of physical parameters of the air at the inlet of the compressor and therefore the compressor aerodynamic performance deteriorates. Sometimes, the turbocharging engine fails to work at some operation points. This paper investigates the effects of various swirl distortions induced by different bending-torsional intake ducts on the aerodynamic performance of a turbocharger compressor by both 3D numerical simulations and experimental measurements. It was found that at the outlet of the pipes the different inlet ducts can generate different swirl distortions, twin vortices and bulk-like vortices with different rotating directions. Among them, the bulk-like vortices not only affect seriously the pressure distribution in the impeller domain, but also significantly deteriorate the compressor performance, especially at high flow rate region. And the rotating direction of the bulk-like vortices is also closely associated with the efficiency penalty. Besides the efficiency, the transient flow rate through a single impeller channel, or the asymmetric mass flow crossing the whole impeller, can be influenced by two disturbances. One is from the upstream bending-torsional ducts; other one is from the downstream volute.

关键词： bending-torsional duct centrifugal compressor swirl distortion relative flow angle

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深冷超声滚压钛合金微观作用机理的研究进展

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工具技术 2024年第9期58卷 3-12页

作者：杨延朝潘永智门秀花朱辰哲付秀丽济南大学机械工程学院

在保持钛合金优良塑、韧性的前提下,提高其强度和硬度以改善其使役性能,突破传统超声滚压塑性变形与晶粒细化的极限,成为钛合金表面强化研究亟待解决的问题。温度和应变率能够改变材料微观塑性变形机制,是解决材料强塑性匹配问题的关键... 详细信息

在保持钛合金优良塑、韧性的前提下,提高其强度和硬度以改善其使役性能,突破传统超声滚压塑性变形与晶粒细化的极限,成为钛合金表面强化研究亟待解决的问题。温度和应变率能够改变材料微观塑性变形机制,是解决材料强塑性匹配问题的关键因素。深冷超声滚压提供了深冷温度和高应变率的外部热、力条件,通过二者的竞争作用协调位错、孪生和相变的微观塑性变形机制,可以进一步提高钛合金性能和寿命。本文在分析温度和应变率影响的基础上,介绍了深冷超声滚压的工作原理及其对钛合金表层性能的强化作用,综述了在超声滚压基础上引入深冷处理的相关试验研究成果,分析了钛合金在深冷超声滚压作用下的微观组织演变规律和塑性变形机制,总结了深冷超声滚压后钛合金微观塑性变形机制与宏观性能的内在关联机制,指出了深冷超声滚压在技术与强化机理方面的发展趋势。

关键词：深冷处理超声滚压高应变率微观组织塑性变形

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Complete Convergence for (α,β)-Mixing Random Variables Sequences

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Wuhan University Journal of Natural Sciences 2013年第4期18卷 327-330页

作者： yang yanzhao Department of Mathematics Qingdao University of Science and Technology

The convergence properties are studied through the analysis of （α,β）-mixing random variables sequences in different situations. By using the corresponding inequality, a convergence theorem was presented, and some results for （α,β）-mixing random variables sequences with different distributions were obtained. The results extend the corresponding theorems of independent random variable sequences.

关键词： complete convergence (α β)-mixing random variables strong law of large numbers

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Spatio-temporal Pattern of Ecosystem Pressure in Countries Along the Belt and Road: Combining Remote Sensing Data and Statistical Data

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Chinese Geographical Science 2022年第5期32卷 745-758页

作者： DU Wenpeng YAN Huimin FENG Zhiming ZHANG Chao yang yanzhao Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Building a Green Silk Road by integrating the Sustainable Development Goals(SDGs) is one of the Belt and Road Initiative(BRI) visions, but the BRI faces enormous challenge that is the conflict between economic development and ecological *** the current scale and trend of the impact of human activities on the ecosystem is the preliminary work to ensure that human activities do not exceed the ecological carrying capacity under the BRI. This study evaluated the ecosystem pressure in countries along the Belt and Road(B&R) from 2000–2017 based on the supply-consumption balance relationship of ecological resources. Net primary productivity(NPP) is taken as the measure of ecological resources, and the supply level and consumption intensity of ecological resources is estimated based on remote sensing data and statistical data, respectively. Results show that thirteen countries with overconsumed ecological resources concentrated in the West Asia/Middle East. Although the intensity of the ecological resource consumption correlated with ecological resource endowments, the ecosystem pressure was determined by social development dependence on the ecological resources at the same ecological resource endowments level. Nearly 80% of countries along the B&R suffered from significantly increased(P < 0.05) ecosystem pressure during 2000–2017, since most of the countries along the B&R were developing countries,and their economic development was highly dependent on ecological resources. Some West Asia/Middle East countries successfully mitigated the ecosystem pressure by importing feed for livestock. Likewise, the Southeast Asian islands benefitted from the import of agricultural products. The results highlight that the BRI should reduce the dependence of social development demands on local ecological resources by international trade for ensuring the increasing ecosystem pressure trend within the ecological carrying capacity.

关键词： Green Silk Road ecosystem pressure net primary productivity(NPP) ecological carrying capacity remote sensing

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超声椭圆振动切削难加工材料的研究进展

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制造技术与机床 2024年第1期 100-107页

作者：孙玉涵张艺嘉杨延朝蒋振峰付秀丽济南大学机械工程学院山东济南250022 淄博大亚金属科技股份有限公司山东淄博255318

超声椭圆振动切削具有断续切削特性的切削优势,已成为国内外研究及应用的热点,尤其适用于脆性材料、复合材料等难加工材料的高性能制造加工领域。目前该技术的机理及对难加工材料的适配工艺方面仍不成熟,需要进一步地探索和实践。通过... 详细信息

超声椭圆振动切削具有断续切削特性的切削优势,已成为国内外研究及应用的热点,尤其适用于脆性材料、复合材料等难加工材料的高性能制造加工领域。目前该技术的机理及对难加工材料的适配工艺方面仍不成熟,需要进一步地探索和实践。通过超声椭圆振动切削机理、特性以及对加工表面质量影响因素的分析,阐明了其在加工中低切削温度、低切削力、低损伤、高尺寸精度以及良好表面完整性的独特优势,综述了在塑性材料、脆性材料、复合材料等难加工材料领域的应用,为后续研究超声椭圆振动切削技术提供了参考。

关键词：难加工材料超声椭圆振动切削加工表面质量

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The Island Rule with lateral and bottom friction

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Acta Oceanologica Sinica 2019年第4期38卷 146-153页

作者： yanzhao yang Zexun Wei Guanlin Wang Zhan Lian Liwei Wang College of Meteorology and Oceanography National University of Defense Technology College of Mathematical Science and Physics Qingdao University of Science and Technology Key Laboratory of Marine Science and Numerical Modeling First Institute of OceanographyMinistry of Natural Resources Laboratory for Regional Oceanography and Numerical Modeling Pilot National Laboratory for Marine Science and Technology (Qingdao)

The Island Rule, derived from the Sverdrup theory, is widely used to estimate and analyze water transport through a strait. Previous studies presented single-or multi-island rules with either lateral or bottom friction. In this paper,an analytical model of wind-driven circulation is assumed based on linear dynamics. Considering both lateral and bottom friction, the analytic solutions of the transport streamfunction around the islands are derived and the volume transport through the channel is presented. The results are similar to those of Wajsowicz, but the frictional constants represent different values. The analytic solution shows that the relationship between the lateral frictional and bottom frictional dissipation is complex in terms of the frictional constants. To understand the interaction between the two friction types, lateral and bottom friction values were randomly chosen on a barotropic beta plane. The result shows an approximately linear relationship between the lateral and bottom friction in consisting of the combined frictional constants. We studied the effect of the channel width on the transport through the channel. The results show that the friction enhances the flow under some widths, which is similar to the flow behavior when only the lateral friction is considered. We also compared the transport through the channel at different depths and founded that the deeper the water, the smaller the transport reduction ratio when the horizontal eddy viscosity coefficient and the bottom drag coefficient remained constants. To further present the combined role of lateral frictional and bottom frictional dissipation, we compared our model with the model of Wajsowicz for two islands, where only the lateral or bottom friction were considered, with different channel widths. The results showed that the effect of the lateral friction is greater than the bottom friction when the channel is narrow, especially in the Munk boundary layer thickness. When the channel is

关键词： Island Rule lateral friction bottom friction transport streamfunction

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Study on the Balance of Agricultural Water and Land Resources on Ningxia Plain

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Chinese Journal of Population,Resources and Environment 2006年第2期4卷 33-40页

作者： Zhang Jing Feng Zhiming yang yanzhao Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China Dezhou Universty Shandong 253023 China

The article puts forward the process and means of regional water and land balance research, and then from two scenarios which are the balances under natural regulation and human intervention, calculated and analysed the balance between water and land on Ningxia Plain. For the balance under natural regulation named farmland water balance, using farmland water resource balance equation, the research estimated the monthly farmland water balance of 8 major crops for all of the 12 counties on Ningxia Plain in the period of 1960-2001; for the balance under human intervention, the research estimated land-use water balance equation of the counties in 2000, and calculated the balance between land use and water resources including irrigating water of all the 12 counties on Ningxia Plain. Results showed that①precipitation can not meet the water demand of the crops for growth and development on Ningxia Plain, and water shortage is the primary character of farmland water balance under natural regulation,②the diversity of water and land balance of different counties is distinctly influenced by the crop structure, water quantity for irrigation and irrigation level.③Irrigation water could meet the crop water demand on Ningxia Plain in 2000, but there was not much space to expand irrigating cultivated land.

关键词： farmland water balance water and land balance sustainable development Ningxia Plain.

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Insights into the rheological modeling of semi-solid metals:Theoretical and simulation study

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Journal of Materials Science & Technology 2022年第5期100卷 182-192页

作者： Zhen Ma Huarui Zhang Hanwei Fu yanzhao yang Jianji Wang Ming Du Hu Zhang School of Materials Science and Engineering Beihang UniversityBeijing 100191China FAW-VOLKSWAGEN Automobile Co. LtdQingdao 266000China Ningbo Institute of Technology Beihang UniversityNingbo 315832China

The power law model is the most widely used model for the rheological behavior of semi-solid metals(SSMs)in the numerical simulation of semi-solid ***,it is still not known why the anomalous negative flow exponent exists in the power law model for SSMs and its influence on the *** this research,the rheological behavior of semi-solid Al-7Si-0.3Mg aluminum alloy is experimentally studied followed by *** power law model fitting results show flow curves deviate from the experimental data and negative flow exponents,which are physically nonsensical and inapplicable to the simulation of SSMs flow proved by hydrodynamic *** drawback of the power law model stems from neglecting the yield stress of *** contrast,the model referring Herschel-Bulkley(HB)theory which takes yield stress into consideration has reasonable flow exponent and yields good agreement between the fitting and experimental ***,the simulation of die filling process is conducted,suggesting that the power law model over-optimistically predicts the tendency of blistering and misrun defects at low temperature and high filling velocity during semi-solid processing.

关键词： Semi-solid metal Rheological behavior Modeling Simulation Aluminum alloys

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Climate Suitability Assessment of Human Settlements for Regions along the Belt and Road

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Chinese Geographical Science 2021年第6期31卷 996-1010页

作者： LIN Yumei LI Peng FENG Zhiming yang yanzhao YOU Zhen ZHU Fuxin Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing100049China National Tibetan Plateau Data Center Key Laboratory of Tibetan Environmental Changes and Land Surface ProcessesInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing100101China

Climate is one important environmental variable that affects human *** the regions along the Belt and Road(B&R)encompass vast territories and large populations,it is significant to assess climate suitability for human settlements,which will influence the migration of various surrounding *** selected seven regions including 65 countries along the B&R for the research area and adopted the temperature-humidity index(THI),to assess the climate *** analyzed the spatial characteristics of THI and the correlation between population distribution and THI,the results of which enabled us to adjust the THI classification *** finally assessed the climate suitability of each *** results reveal that outside the Qinghai-Tibet Plateau,the THI values generally tend to decrease from west to east as longitude increases and downward with increasing *** population distribution is significantly correlated with the *** with relative suitable climate,including high suitability areas(HASs),moderately suitable areas(MSAs)and low suitability areas(LSAs),account for 50.62%of the total area and encompass in excess of 90%of total *** areas are widely distributed in the southern regions of 45°N latitude,again with the exception of the Qinghai-Tibet *** suitable area includes 19.48%of the entire area and 8.98%of total *** non-suitable area accounts for less than 30%of total area,concentrated in the cold high-latitude and high-altitude areas.

关键词： climate suitability temperature-humidity index human settlements spatial distribution the Belt and Road

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