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Experimental Study of Bowed-twisted Stators in an Axial Transonic Fan Stage

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Chinese Journal of Aeronautics 2009年第4期22卷 364-370页

作者： Chen Fu,Li Shaobin,su Jiexian,wang Zhongqi School of Energy Science and Engineering,Harbin Institute of Technology,Harbin 150001,China School of Energy Science and Engineering Harbin Institute of Technology Harbin 150001 China

Bowed-twisted stators with large camber angles have been developed to replace the conventional tandem stators in an axial transonic fan stage working at high subsonic speeds. Experimental study is carried out on both stages with tandem stators and with bowed-twisted stators. Compared to the tandem stators, the bowed-twisted stators change the distribution of the low-energy fluid and the potential high-energy fluid at the compressor outlets, reduce the endwall loss significantly, improve the aerody- namic matching of rotors and stators, and eventually increase the fan stage performances. The aerodynamic performances of the fan stage at different operating points are compared and contrasted. The results show that the transonic fan stage with bowed-twisted stators has better aerodynamic performances. It is thus suggested that the bowed-twisted stators with large camber angles be popularized into the high-loaded transonic fan designs.

关键词： large camber angle bowed-twisted stator aerodynamic performance transonic fan stage

Performance Evaluation of Land Use Regulation

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Chinese Journal of Population,Resources and Environment 2010年第1期8卷 28-31页

作者： wang Yumeng Wu Juan fang Lingli Zhang Anlu College of Land Management Huazhong Agricultural University Wuhan Hubei 430070 China College of Politics and Law and Public Administration Hubei University Wuhan Hubei 430062 China

This article makes a quantitative study on economic performance of arable land protection and land use regulation with dummy variable *** is shown that land use regulation is favorable for economic growth and protection of arable land and that there are still some problems in the implementation of land use ***,it puts forward corresponding suggestion.

关键词： regulation of land use performance evaluation suggestion

Designing heterostructured FeP–CoP for oxygen evolution reaction:Interface engineering to enhance electrocatalytic performance

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Nano Research 2023年第5期16卷 6601-6607页

作者： Shuang Hou Ansai Zhang Qi Zhou Yingjie Wen Sixie Zhang Linfeng su Xinjie Huang Tian wang Kun Rui Cheng wang Huiling Liu Zhiyi Lu Peilei He Institute for New Energy Materials and Low-Carbon Technologies School of Materials Science and EngineeringTianjin Key Laboratory of Advanced Functional Porous MaterialsTianjin University of TechnologyTianjin 300384China Institute of New Energy Technology Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Flexible Electronics(KLOFE) Institute of Advanced Materials(IAM)Nanjing Tech University(NanjingTech)Nanjing 211816China

It is significant to develop highly efficient electrocatalysts for energy conversion *** engineering is one of the most feasible approaches to effectively enhance the electrocatalytic ***,the density functional theory(DFT)calculations predict that the potential barriers of Fe sites at the interface of FeP–CoP heterostructures are lower than that of Fe sites in FeP nanoparticles(NPs),Co sites in CoP NPs,or Co sites in *** by the DFT calculation results,FeP–CoP heterostructures have been designed and synthesized by a metal–organic frameworks(MOFs)confined-phosphorization *** FeP–CoP exhibits the lowest overpotential of 230 mV at the current density of 10 mA·cm^(−2)for oxygen evolution reaction(OER),compared with FeP(470 mV)and CoP(340 mV),which outperforms most of transition metal-based *** Tafel analysis of FeP–CoP heterostructures shows an improved reaction kinetic pathway with the smallest slope of 90.3 mV·dec^(−1),as compared to the Tafel slopes of FeP NPs(137 mV·dec^(−1))and CoP NPs(114 mV·dec^(−1)).And the FeP–CoP shows extraordinary long-term stability over 24 *** excellent activity and long-term stability of FeP–CoP derive from the synergistic effect between FeP and CoP.

关键词： electrocatalysts interface engineering FeP–CoP heterostructures oxygen evolution reaction synergistic effect

Satellite UV-Vis spectroscopy:implications for air quality trends and their driving forces in China during 2005-2017

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Light(Science & Applications) 2019年第1期8卷 246-257页

作者： Chengxin Zhang Cheng Liu Qihou Hu Zhaonan Cai Wenjing su Congzi Xia Yizhi Zhu Siwen wang Jianguo Liu School of Earth and Space Sciences University of Science and Technology of China230026 HefeiChina Department of Precision Machinery and Precision Instrumentation University of Science and Technology of China230026 HefeiChina Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsChinese Academy of Sciences230031 HefeiChina Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of Sciences361021 XiamenChina Key Laboratory of Precision Scientific Instrumentation of Anhui Higher Education Institutes University of Science and Technology of China230026 HefeiChina Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of Sciences100029 BeijingChina Multiphase Chemistry Department Max Planck Institute for Chemistry55128 MainzGermany

Abundances of a range of air pollutants can be inferred from satellite UV-Vis spectroscopy measurements by using the unique absorption signatures of gas ***,we implemented several spectral fitting methods to retrieve tropospheric NO_(2),SO_(2),and HCHO from the ozone monitoring instrument(OMI),with radiative simulations providing necessary information on the interactions of scattered solar light within the *** analyzed the spatial distribution and temporal trends of satellite-observed air pollutants over eastern China during 2005-2017,especially in heavily polluted *** found significant decreasing trends in NO_(2) and SO_(2) since 2011 over most regions,despite varying temporal features and turning *** contrast,an overall increasing trend was identified for tropospheric HCHO over these regions in recent ***,generalized additive models were implemented to understand the driving forces of air quality trends in China and assess the effectiveness of emission *** results indicated that although meteorological parameters,such as wind,water vapor,solar radiation and temperature,mainly dominated the day-to-day and seasonal fluctuations in air pollutants,anthropogenic emissions played a unique role in the long-term variation in the ambient concentrations of NO_(2),SO_(2),and HCHO in the past 13 ***,recent declines in NO_(2) and SO_(2) could be attributed to emission reductions due to effective air quality policies,and the opposite trends in HCHO may urge the need to control anthropogenic volatile organic compound(VOC)emissions.

关键词： driving forces spectroscopy

Foam-like boron-doped g-C_(3)N_(4) as acid-base cooperative catalyst for efficient nucleophilic addition in water

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Green Chemical Engineering 2021年第2期2卷 239-249页

作者： Jiajun wang Zewei Liu Shiye Li Chaoping Li su Liu Jingwen Feng Rong Tan National&Local Joint Engineering Laboratory for New Petro-chemical Materials and Fine Utilization of Resources Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research(Ministry of Education)Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan ProvinceCollege of Chemistry&Chemical EngineeringHunan Normal UniversityNo.36South Lushan RoadChangshaHunan410081China

Intramolecular acid-base cooperative catalysis is a powerful strategy to promote the nucleophilic additions in synthetic chemistry,since both substrates and nucleophiles can be activated simultaneously,yielding a lower energy reaction ***,the systems often suffer from catalyst quenching due to the mutual neutralization of acid/base ***,we doped the boron(B)atoms in the tri-s-triazine ring of graphite-like carbon nitride(g-C_(3)N_(4))framework,to develop the acid-base cooperative catalyst for nucleophilic *** results demonstrated a foam-like hierarchical porous structure,as well as the coexistence of Lewis acid and base sites in the as-synthesized *** a result,the B-doped g-C_(3)N_(4) acted as the efficient acidbase cooperative catalysts,significantly promoting the Knoevenagel condensation whose key step involves in nucleophilic addition.A wide range of α,β-unsaturated carbonyl compounds with remarkably high yields(>90%)was achieved even within 1 h in water,whereas the acid-free or base-free counterpart was far less *** addition,the bifunctional catalysts exhibited excellent reusability with simple *** novel B-doped g-C_(3)N_(4) catalytic system offers several advantages,such as operational simplicity,mild reaction conditions,high efficiency,and facile reuse of *** these advantages make it a benign protocol from the sustainability point of view,and inspired us to design the other bifunctional cooperative catalysts for a wide range of sustainable industrial applications.

关键词： Acid-base cooperative catalysis Boron-doping g-C_(3)N_(4) Knoevenagel condensation Water

Effects of Biochar Inoculation with Bacillus megaterium on Rice Soil Phosphorus Fraction Transformation and Bacterial Community Dynamics

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Rice science 2024年第4期31卷 361-365,I0001-I0003页

作者： YU Keru XUE Zhaokun fang Xianzhi MA Jiawei wang Yongjun LIU Dan YE Zhengqian State Key Laboratory of subtropical Silviculture Zhejiang A&F UniversityHangzhou 311300China Key Laboratory of Soil Contamination Bioremediation of Zhejiang Province Zhejiang A&F UniversityHangzhou 311300China Department of Forest Protection College of Forestry and BiotechnologyZhejiang A&F UniversityHangzhou 311300China

Rice husk biochar inoculated with Bacillus megaterium(BM)(referred to as BM-inoculated biochar, BMB) and uninoculated rice husk biochar(RHB) were added to soil at two rates(0.5%, as BMB1 and RHB1, respectively, and 1.0%, as BMB2 and RHB2, respectively) in an incubation experiment to comprehensively evaluate their effects on basic soil properties, phosphorus(P) fractions, bacterial community composition, and P-cycling genes.

关键词： soil comprehensive Transformation

High-speed electro-optic modulation in topological interface states of a one-dimensional lattice

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Light(Science & Applications) 2023年第9期12卷 1961-1970页

作者： Yong Zhang Jian Shen Jingchi Li Hongwei wang Chenglong Feng Lei Zhang Lu sun Jian Xu Ming Liu Ying wang Yonghui Tian Jianwen Dong Yikai su State Key Laboratory of Advanced Optical Communication Systems and Networks Department of Electronic EngineeringShanghai Jiao Tong UniversityShanghai 200240China Center for Advanced Electronic Materials and Devices Shanghai Jiao Tong UniversityShanghai 200240China Institute of Microelectronics and Key Laboratory for Magnetism and Magnetic Materials of MOE School of Physical Science and TechnologyLanzhou UniversityLanzhou 730000 GansuChina State Key Laboratory of Optoelectronic Materials and Technologies&School of Physics Sun Yat-sen UniversityGuangzhou 510275China

lectro-optic modulators are key components in data communication,microwave photonics,and quantum *** bandwidth,energy efficiency,and device dimension are crucial metrics of ***,we provide an important direction for the miniaturization of electro-optic modulators by reporting on ultracompact topological modulators.A topological interface state in a one-dimensional lattice is implemented on a thin-film lithium-niobate integrated *** to the strong optical confinement of the interface state and the peaking enhancement of the electro-optic response,a topological cavity with a size of 1.6×140μm^(2)enables a large modulation bandwidth of 104 *** first topological modulator exhibits the most compact device size compared to reported LN modulators with bandwidths above 28 GHz,to the best of our knowledge.100 Gb/s non-return-to-zero and 100 Gb/s four-level pulse amplitude modulation signals are *** switching energy is 5.4 fJ/bit,owing to the small electro-optic mode volume and low *** topological modulator accelerates the response time of topological photonic devices from the microsecond order to the picosecond order and provides an essential foundation for the implementation of large-scale lithium-niobate photonic integrated circuits.

关键词： modulator interface lattice

Coordinated Ramp Metering and Intersection Signal Control

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International Journal of Transportation Science and Technology 2014年第2期3卷 179-192页

作者： Dongyan su Xiao-Yun Lu Roberto Horowitz Zhongren wang University of California Bekeley2167c Etcheverry HallUniversity of CaliforniaBerkeleyCA 94720-1740 PATH ITSUniversion of CaliforniaBerkeleySBldg 4521357 S.46th StreetRichmondCA 94804-4648 University of California Bekeley5138 Etcheverry HallUniversity of CaliforniaBerkeleyCA 94720-1740 State-wide Ramp Metering Program Manager Caltrans1120 N StMS-36SacramentoCA 95814

The operations of freeway ramp metering and urban traffic network signal control are independent in most *** situation may cause some conflict between traffic streams of the two subsystems,or,at least,their dynamic interactions have not been taken into account from an overall system *** performance can be improved if the controls of these two sub-networks are *** paper proposes a novel signal control strategy for the feeding intersection and a coordination strategy for integrating it with the corresponding freeway onramp *** ALINEA with queue-overwrite is used for the ramp metering.A signal optimization,which takes into account the available ramp space and traffic demand,is developed for intersection signal control.A calibrated micro-simulation is used to compare the proposed control/coordination strategies and current control plans in the *** result shows that,even though the overall system performance only gets a marginal improvement,intersection delay reduces significantly.

关键词： coordination intersection integrating

The historical evolution of the regulations for the Florence Nightingale Medal

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Frontiers of Nursing 2018年第1期5卷 1-5页

作者： Qian wang Rui-fang Zhu Zhi-Guang Duan School of Nursing Shanxi Medical UniversityTaiyuanShanxi 030001China First Hospital of Shanxi Medical University TaiyuanShanxi 030001China

Objective: This study aimed to explore the 100-year changes in regulations for the Florence Nightingale ***: We used the announcements of the Florence Nightingale Medal awards as the research object to analyze-via historical and inductive methods-the regulations for receiving the Florence Nightingale ***: In the award years, the greatest number of winners per award year was 71 and the lowest was 12. The medal was initially exclusively awarded to living people but evolved to include both living and deceased people. The recipients were balanced among all countries. The gender of the winners showed a changing trend from being limited to only females to including both males and *** was also a shift from emphasis on only dedication of the recipient to equal emphasis on both dedication and ***: The selection criteria for recipients of the Florence Nightingale Medal evolved from consideration of those showing only dedication to equal consideration of both dedication and innovation.

关键词： Florence Nightingale Medal Florence Nightingale Medal awards dedication innovation evolution regulations