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Assessment of Wet Season Precipitation in the Central United States by the Regional Climate Simulation of the WRFG Member in NARCCAP and Its Relationship with Large-Scale Circulation Biases

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Advances in Atmospheric Sciences 2024年第4期41卷 619-638页

作者： Yating ZHAO ming XUE Jing JIANG Xiao-ming hu Anning huANG School of Atmospheric Sciences Nanjing UniversityNanjing 210023China Center for Analysis and Prediction of Storms and School of Meteorology The University of OklahomaNorman 73072U.S.A

Assessment of past-climate simulations of regional climate models(RCMs)is important for understanding the reliability of RCMs when used to project future regional ***,we assess the performance and discuss possible causes of biases in a WRF-based RCM with a grid spacing of 50 km,named WRFG,from the North American Regional Climate Change Assessment Program(NARCCAP)in simulating wet season precipitation over the Central United States for a period when observational data are *** RCM reproduces key features of the precipitation distribution characteristics during late spring to early summer,although it tends to underestimate the magnitude of *** dry bias is partially due to the model’s lack of skill in simulating nocturnal precipitation related to the lack of eastward propagating convective systems in the *** in reproducing large-scale circulation and environmental conditions is another contributing *** too weak simulated pressure gradient between the Rocky Mountains and the Gulf of Mexico results in weaker southerly winds in between,leading to a reduction of warm moist air transport from the Gulf to the Central Great *** simulated low-level horizontal convergence fields are less favorable for upward motion than in the NARR and hence,for the development of moist convection as ***,a careful examination of an RCM’s deficiencies and the identification of the source of errors are important when using the RCM to project precipitation changes in future climate scenarios.

关键词： NARCCAP Central United States precipitation low-level jet large-scale environment diurnal variation

Ferrite features in simulated transition zone of EH36 shipbuilding steel submerged arc welded by CaF_(2)-SiO_(2)-MnO fluxes

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Journal of Iron and Steel Research(International) 2024年第4期31卷 790-796页

作者： ming Zhong Dong hu Da-ming Guo Somnath Basu Cong Wang Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819LiaoningChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Department of Metallurgical Engineering and Materials Science Indian Institute of Technology BombayMumbai 400076MaharashtraIndia

Ferrite features in the simulated transition zone welded with CaF_(2)-SiO_(2)-MnO fluxes containing various MnO contents have been *** laser scanning microscopy has been applied to simulate the thermal cycling of the transition zone and the phase transformations during cooling have been in-situ *** has been found that the appearance temperature for ferrite side plate decreases with increasing Mn content in the weld metals caused by MnO content ***,growth rates for both ferrite side plate and acicular ferrite are significantly enhanced with a higher Mn content of weld ***,from the statistical fractions of salient microstructures,for all samples,the acicular ferrite,grain boundary ferrite,and polygonal ferrite take over more than 90%.It has also been demonstrated that with the increase in Mn content,the ferrite side plate fraction increases slightly from 5%to 10%and the acicular ferrite fraction shows a tendency of first increasing and then decreasing,which experiences the maximum with the flux containing 30 wt.%*** phenomenon is believed to be controlled by the O and Mn contents in weld metals synergistically.

关键词： Submerged arc welding Transition zone Phase transformation Microstructure

A Quasi-Linear Relationship between Planetary Outgoing Longwave Radiation and Surface Temperature in a Radiative-Convective-Transportive Climate Model of a Gray Atmosphere

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Advances in Atmospheric Sciences 2024年第1期41卷 8-18页

作者： Jie SUN Michael SECOR ming CAI Xiaoming hu Department of Earth Oceanand Atmospheric ScienceFlorida State UniversityTallahasseeFlorida 32304USA School of Atmospheric Sciences Sun Yat-sen University and Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies Zhuhai 519082China

In this study,we put forward a radiative-convective-transportive energy balance model of a gray atmosphere to examine individual roles of the greenhouse effect of water vapor,vertical convection,and atmospheric poleward energy transport as well as their combined effects for a quasi-linear relationship between the outgoing longwave radiation(OLR)and surface temperature(T_(S)).The greenhouse effect of water vapor enhances the meridional gradient of surface temperature,thereby directly contributing to a quasi-linear OLR-T_(S) *** atmospheric poleward energy transport decreases the meridional gradient of surface *** a result of the poleward energy transport,tropical(high-latitude)atmosphere-surface columns emit less(more)OLR than the solar energy input at their respective locations,causing a substantial reduction of the meridional gradient of the *** combined effect of reducing the meridional gradients of both OLR and surface temperature by the poleward energy transport also contributes to the quasi-linear OLR-T_(S) *** convective energy transport reduces the meridional gradient of surface temperature without affecting the meridional gradient of OLR,thereby suppressing part of the reduction to the increasing rate of OLR with surface temperature by the greenhouse effect of water vapor and poleward energy *** of the nature of the energy balance in the climate system,such a quasi-linear relationship is also a good approximation for the relationship between the annual-mean net downward solar energy flux at the top of the atmosphere and surface temperature.

关键词： outgoing longwave radiation greenhouse effect poleward energy transport

Experimental study of face passive failure features of a shallow shield tunnel in coastal backfill sand

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Frontiers of Structural and Civil Engineering 2024年第2期18卷 252-271页

作者： Weifeng QIAN ming huANG Bingnan WANG Chaoshui XU Yanfeng hu School of Civil Engineering Fuzhou UniversityFuzhou 350108China School of Civil Environment and Mining EngineeringUniversity of AdelaideAdelaide 5005Australia China First Highway Xiamen Engineering Co. Ltd.Xiamen 361000China

Face passive failure can severely damage existing structures and underground utilities during shallow shield tunneling,especially in coastal backfill *** this work,a series of laboratory model tests were developed and conducted to investigate such failure,for tunnels located at burial depth ratios for which C/D=0.5,0.8,1,and *** pressures,the evolution of failure processes,the failure modes,and the distribution of velocity fields were examined through model tests and numerical *** support pressure in the tests first rose rapidly to the elastic limit and then gradually increased to the maximum value in all *** maximum support pressure decreased slightly in cases where C/D=0.8,1,and 1.3,but the rebound was insignificant where C/D=*** addition,the configuration of the failure mode with C/D=0.5 showed a wedge-shaped arch,which was determined by the outcropping shear *** configuration of failure modes was composed of an arch and the inverted trapezoid when C/D=0.8,1,and 1.3,in which the mode was divided into lower and upper failure zones.

关键词： tunnel face stability passive failure model test support pressure failure mode

Buried interface management via bifunctional NH_(4)BF_(4)towards efficient CsPbI_(2)Br solar cells with a V_(oc)over 1.4 V

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Journal of Energy Chemistry 2024年第2期89卷 364-370,I0009页

作者： Fazheng Qiu ming-hua Li Jinpeng Wu Jin-Song hu School of Materials Science and Engineering NingboTech UniversityNingbo 315100ZhejiangChina Beijing National Laboratory for Molecular Sciences(BNLMS) Institute of ChemistryChinese Academy of SciencesBeijing 100190China College of Chemical Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China

CsPbI_(2)Br perovskite solar cells(PSCs)have drawn tremendous attention due to their suitable bandgap,excellent photothermal stability,and great potential as an ideal candidate for top cells in tandem solar ***,the abundant defects at the buried interface and perovskite layer induce severe charge recombination,resulting in the open-circuit voltage(V_(oc))output and stability much lower than ***,a novel buried interface management strategy is developed to regulate interfacial carrier dynamics and CsPbI_(2)Br defects by introducing ammonium tetrafluoroborate(NH_(4)BF_(4)),thereby resulting in both high CsPbI_(2)Br crystallization and minimized interfacial energy ***,NH_(4)^(+)ions could preferentially heal hydroxyl groups on the SnO_(2)surface and balance energy level alignment between SnO_(2)and CsPbI_(2)Br,enhancing charge transport efficiency,while BF_(4)^(-)anions as a quasi-halogen regulate crystal growth of CsPbI_(2)Br,thus reducing perovskite ***,it is proved that eliminating hydroxyl groups at the buried interface enhances the iodide migration activation energy of CsPbI_(2)Br for strengthening the phase *** a result,the optimized CsPbI_(2)Br PSCs realize a remarkable efficiency of 17.09%and an ultrahigh V_(oc)output of 1.43 V,which is one of the highest values for CsPbI_(2)Br PSCs.

关键词： Inorganic perovskite Buried interface Defect Stability Open-circuit voltage loss

Effect of wire mesh casing treatment on axial compressor performance and stability

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Chinese Journal of Aeronautics 2024年第3期37卷 60-76页

作者： ming ZHANG Jiaming ZHANG Jiahao hu Xu DONG Dakun SUN Xiaofeng SUN School of Energy and Power Engineering Beihang UniversityBeijing 100191China Beihang Hangzhou Innovation Institute Yuhang Hangzhou 310023China National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics Beihang UniversityBeijing 100191China

In this paper,a kind of Wire Mesh Casing Treatment(WMCT)is proposed to improve the stable operating range of the *** contrast to the traditional circumferential groove,as for WMCT,a layer of wire mesh is laid on the surface of the circumferential *** studies were conducted on the low-speed axial flow compressor,including the groove width,axial location,and mesh *** optimum axial location for WMCT is related to its groove width.A higher wire mesh count results in a smaller compressor stall margin *** simulations were carried out to study the effect of WMCT on the flow structure of the *** wire mesh in the WMCT has a certain flow resistance,which restricts the flow into and out of the *** to the WMCT,the flow parameter in the tip region of the rotor is less sensitive to changes in the operating conditions of the *** WMCT causes the rotor tip blade loading to shift backward,inhibiting the formation of spill forward of the leakage flow,and thus improving the stability of the *** flow resistance on the groove surface is a new degree-of-freedom for the casing treatment designer.

关键词： Axial compressor Wire mesh casing treatment Tip clearance flow Stall margin Blade loading

Manufacturing task data chain-driven production logistics trajectory analysis and optimization decision making method

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Advances in Manufacturing 2024年第1期12卷 185-206页

作者： Lin Ling Zhe-ming Song Xi Zhang Peng-Zhou Cao Xiao-Qiao Wang Cong-hu Liu ming-Zhou Liu School of Mechanical Engineering Hefei University of TechnologyHefei230009People’s Republic of China Guobo Electronics Co.Ltd. Nanjing211111People’s Republic of China School of Mechanical and Electronic Engineering Suzhou UniversitySuzhou234000AnhuiPeople’s Republic of China Sino-US Global Logistics Institute Shanghai Jiao Tong UniversityShanghai200030People’s Republic of China

Production logistics(PL)is considered as a critical factor that affects the efficiency and cost of production operations in discrete manufacturing *** effectively utilize manufacturing big data to improve PL efficiency and promote job shop floor economic benefits,this study proposes a PL trajectory analysis and optimization decision making method driven by a manufacturing task data chain(MTDC).First,the manufacturing task chain(MTC)is defined to characterize the discrete production process of a *** handle manufacturing big data,the MTC data paradigm is designed,and the MTDC is ***,the logistics trajectory model is presented,where the various types of logistics trajectories are extracted using the MTC as the search engine for the *** on this,a logistics efficiency evaluation indicator system is proposed to support the optimization decision making for the ***,a case study is applied to verify the proposed method,and the method determines the PL optimization decisions for PL efficiency without changing the layout and workshop equipment,which can assist managers in implementing the optimization decisions.

关键词： Production logistics(PL) Logistics trajectory analysis Logistics optimization Data driven Manufacturing task data chain(MTDC)

Near real-time gravitational wave data analysis of the massive black hole binary with TianQin

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 175-186页

作者： Hong-Yu Chen Xiang-Yu Lyu En-Kun Li Yi-ming hu MOE Key Laboratory of TianQin Mission TianQin Research Center for Gravitational Physics&School of Physics and AstronomyFrontiers Science Center for TianQinGravitational Wave Research Center of CNSASun Yat-sen University(Zhuhai Campus)Zhuhai 519082China

Space-borne gravitational wave(GW)detectors can detect the merger of massive black *** early warning and localization of GW events before merging can be used to inform electromagnetic telescopes and conduct multimessenger ***,this requires real-time data transmission and analysis *** geocentric orbit of the space-borne GW detector Tian Qin makes it possible to conduct real-time data *** this study,we develop a search and localization pipeline for massive black hole binaries(MBHBs)with Tian Qin under both regular and real-time data transmission *** demonstrate that,with real-time data transmission,MBHBs can be accurately localized on the *** the approaching merger,each analysis can be finished in only 40 *** an MBHB system at a distance of 1 Gpc,if we receive data every hour,then we can pinpoint its location to within less than 1 deg^(2)on the final day before the merger.

关键词： gravitational wave detectors and experiments black holes data analysis algorithms and implementation data management

Preparation of Chemically Recyclable Poly(ether-alt-ester) by the Ring Opening Polymerization of Cyclic Monomers Synthesized by Coupling Glycolide and Epoxides

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Chinese Journal of Polymer Science 2024年第2期42卷 168-175,I0006页

作者： Feng Ren Zhuang-Zhuang Liang ming-Xin Niu Chen-Yang hu Xuan Pang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China

Polyester and polyether are two key oxygenated polymers, and completely alternative sequence of poly(ester-alt-ether) could efficiently combine the advantages(including flexibility, degradability, etc.) of both segments. Currently, despite their copolymers could be synthesized from one-pot mixture of cyclic esters and epoxides, perfectly alternative microstructure is very challenging to realize and typically restricted to certain monomer pairs. Moving forward, synthesizing poly(ester-alt-ether) from commercially available and largescale monomers would be a significant advance. For example, successfully commercialized poly(glycolic acid)(PGA), which is not easily soluble in polymers due to its high crystallinity and is brittle and difficult to control the degradation cycle, would encounter a new paradigm if engineered into poly(ester-altether). In this work, starting from the design of monomer with hybrid structures, we successfully synthesized a series of 1,4-dioxan-2-one containing different substituents based on glycolide(GA) and epoxides using commercially available Salen-Cr(III) and PPNCl catalytic *** new monomers underwent ring-opening polymerization(ROP) to form a series of poly(ester-alt-ether) with perfectly alternating glycolic acid and propylene glycol repeat units under catalytic system of thiourea/base. The poly(ester-alt-ether) have significantly lower glass-transition temperature than PGA. Additionally, the poly(ester-alt-ether) can be chemically recovered to monomer using Sn(Oct)2 or 1,8-diazabicyclo[5.4.0]undecane-7-ene(DBU) as a catalyst in solution, thus establishing a closed-loop life cycle. From monomers derived from GA and epoxides, this work furnishes a novel strategy for the synthesis of poly(ester-alt-ether) with chemical recyclability.

关键词： Polyester Polyether Alternative copolymer Ring-opening polymerization