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Effect of Temperature on Microstructure and Formability of Al-10 mass% Si Coatings

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Journal of Iron and Steel Research International 2016年第3期23卷 270-275页

作者： Jie ZHANG she-ming jiang Qi-fu ZHANG Chang-sheng LIU National Engineering Laboratory Advanced Coating Technology for Metals Central Iron and Steel Research InstituteBeijing 100081China School of Materials and Metallurgy Northeastern UniversityShenyang 110004LiaoningChina

The type-1aluminized（Al-10mass% Si）coating on hot stamped steel is used in commercial *** effect of temperature on microstructure and formability of the Al-10mass% Si coating was ***-dip aluminized 22MnB5 steel was heated at 870,900,930,and 1 050 ℃ for 5 *** heat treatment at different temperatures,the microstructure of Al-10mass% Si was characterized by field-emission scanning electron microscopy and energy-dispersive *** results show that when the Al-10mass% Si coating was heated at 870℃for 5min,three types of intermetallic phases were formed：two ternary Fe-Si-Al phases（Fe2SiAl7＋Fe2Si2Al5and Fe2SiAl2＋Fe2Si2Al5）and one binary Fe-Al phase（FeAl3）.The phases in the coating became Fe2SiAl2＋Fe2Si2Al5and FeAl3,the binary Fe-Al phase near the interface became Fe2Al5 and the Si-rich layers were decreased with the increase of heating *** the heat treatment was 1 050℃for 5min,the Si-rich layer disappeared,the coating consisted of FeAl and Fe3 Al,and the Kirkendall voids were *** the heating temperature was increased through 870,900,and 930℃,the coating hardness was reduced and cracks were formed in the coating after hot *** formability of the coating with temperature change was confirmed by a hot stamping *** heated at 1 050 ℃,the coating was formable but continuous Kirkendall voids were observed.

关键词： Al-Si coating heating temperature microstructure formability hot-stamping

Influence of Surface Roughness of Galvanized Steel sheet on Self-lubricated Coating

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Journal of Iron and Steel Research International 2014年第3期21卷 342-347页

作者： Xin LIU Wu-gang YU Qi-fu ZHANG she-ming jiang National Engineering Laboratory of Advanced Coating Technology for Metal Materials Central Iron and Steel Research Institute School of Materials Science and Engineering University of Science and Technology Beijing

Three different thicknesses of self-lubricated coatings were prepared on galvanized steel sheets with differ- ent surface roughness （Ra）. Performances of the coatings were evaluated by various laboratory tests. Scanning elec- tron microscopy （SEM）, atomic force microscope （AFM）, neutral salt spraying test （NSST）, reciprocating friction and wear test were taken in order to characterize the coatings. Results show that the self-lubricated coating has good corrosion resistance and lubricating property. In 0. 857--1. 629 /~m of Ra value, the relationship between friction co- efficients of the self lubricated steel sheets and the surface roughness of the galvanized steel sheets likes a parabolic curve, and has a peak value of friction coefficient in certain range of Ra. Affected by the hereditary surface topogra- phy of the galvanized steel sheet, dents on the surface of sel^lubricated steel become deeper and larger with the in crease of the surface roughness of the galvanized steel sheets. The influence of the surface roughness of the galvanized steel sheet on the corrosion resistance of the self lubricated coating steel is similar to that on friction coefficient of selPlubricated coatings, like a parabolic curve.

关键词： surface roughness self-lubricated friction coefficient corrosion resistance

Influence of Oxide Morphologies on Galvanizability of Third Generation Automotive Steel

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Journal of Iron and Steel Research International 2014年第11期21卷 1059-1064页

作者： she-ming jiang Shi-jie FENG Xun-hua YUAN Yuan-peng LI Zhen-hua LI Qi-fu ZHANG National Engineering Laboratory of Advanced Coating Technology for Metal Materials Central Iron and Steel Research Institute Faculty of Material Science and Engineering Kunming University of Science and Technology

Focusing on improving the galvanizability of the third generation automotive steel, the effect of surface ox ide morphologies on the galvanizability was studied. The results show that the surface oxide types of sample steels by X ray photoelectron spectroscopy （XPS） analysis after annealing in different conditions are the same. Only MnO, MnO2 and Cr2O3 were detected and no complex oxide exists on the surface. Morphologies of surface oxides can greatly influence the galvanizability of the third generation automotive steel. Nodule-like oxide surface can contribute to better wettability and inhibition layer than vitreous film like oxide surface. Galvanized panels of nodule-like oxide surface steels only show pinhole sized bare spots, while panels galvanized from vitreous film-like oxide surface steels reveal larger areas of bare spots and uncoated areas. Inhibition layer observed in galvanized panels of nodule-like oxide surface steels is compact but not homogeneous; some inhibition layer grains are fine, and others are coarse, while the inhibition layer grains of panels galvanized from vitreous film-like oxide surface steels have a non-compact morphology with some particularly fine equiaxed crystals which developed deficiently.

关键词： galvanizing third generation automotive steel oxide morphology galvanizability

An improved initial rotor position estimation method using high-frequency pulsating voltage injection for PMSM

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Defence Technology（防务技术） 2024年第3期33卷 19-29页

作者： Yang jiang ming Cheng School of Electrical Engineering Southeast UniversityNanjing 210096China

High frequency pulsating voltage injection method is a good candidate for detecting the initial rotor position of permanent magnet synchronous ***,traditional methods require a large number of filters,which leads to the deterioration of system stability and dynamic *** order to solve these problems,a new signal demodulation method is proposed in this *** proposed new method can directly obtain the amplitude of high-frequency current,thus eliminating the use of filters,improving system stability and dynamic performance and saving the work of adjusting filter *** addition,a new magnetic polarity detection method is proposed,which is robust to current measurement ***,experiments verify the effectiveness of the method.

关键词： Initial position detection Signal demodulation algorithm Magnetic polarity detection Filter elimination

On the Strong Approximation for a Simple Reentrant Line in Light Traffic Under First-buffer First-served Service Discipline

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 823-839页

作者： Kai-ming YANG Yong-jiang GUO School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China

For a 2-station and 3-class reentrant line under first-buffer first-served(FBFS)service discipline in light traffic,we firstly construct the strong approximations for performance measures including the queue length,workload,busy time and idle time *** on the obtained strong approximations,we use a strong approximation method to find all the law of the iterated logarithms(LILs)for the above four performance measures,which are expressed as some functions of system parameters:means and variances of interarrival and service times,and characterize the fluctuations around their fluid approximations.

关键词： reentrant line queueing network FBFS service discipline strong approximation LIL Brownian motion

Drug-Target Interactions Prediction Based on Signed Heterogeneous Graph Neural Networks

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Chinese Journal of Electronics 2024年第1期33卷 231-244页

作者： ming CHEN Yajian jiang Xiujuan LEI Yi PAN Chunyan JI Wei jiang College of Information Science and Engineering Hunan Normal University School of Computer Science Shaanxi Normal University Faculty of Computer Science and Control Engineering Shenzhen Institute of Advanced TechnologyChinese Academy of Sciences Computer Science Department BNU-HKBU United International College

Drug-target interactions(DTIs) prediction plays an important role in the process of drug *** computational methods treat it as a binary prediction problem, determining whether there are connections between drugs and targets while ignoring relational types information. Considering the positive or negative effects of DTIs will facilitate the study on comprehensive mechanisms of multiple drugs on a common target, in this work, we model DTIs on signed heterogeneous networks, through categorizing interaction patterns of DTIs and additionally extracting interactions within drug pairs and target protein pairs. We propose signed heterogeneous graph neural networks(SHGNNs), further put forward an end-to-end framework for signed DTIs prediction, called SHGNN-DTI,which not only adapts to signed bipartite networks, but also could naturally incorporate auxiliary information from drug-drug interactions(DDIs) and protein-protein interactions(PPIs). For the framework, we solve the message passing and aggregation problem on signed DTI networks, and consider different training modes on the whole networks consisting of DTIs, DDIs and PPIs. Experiments are conducted on two datasets extracted from Drug Bank and related databases, under different settings of initial inputs, embedding dimensions and training modes. The prediction results show excellent performance in terms of metric indicators, and the feasibility is further verified by the case study with two drugs on breast cancer.

关键词： Drugs Training Proteins Measurement Message passing Prediction methods Graph neural networks

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

Could natural phytochemicals be used to reduce nitrogen excretion and excreta‑derived N_(2)O emissions from ruminants?

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Journal of Animal Science and Biotechnology 2024年第2期15卷 490-508页

作者： Yuchao Zhao ming Liu Linshu jiang Leluo Guan Beijing Key Laboratory of Dairy Cow Nutrition College of Animal Science and TechnologyBeijing University of AgricultureBeijing 102206China College of Animal Science and Technology China Agricultural UniversityBeijing 100193China Department of Agricultural Food and Nutritional ScienceUniversity of AlbertaEdmontonAB T6G 2R3Canada

Ruminants play a critical role in our food system by converting plant biomass that humans cannot or choose not to consume into edible high-quality ***,ruminant excreta is a significant source of nitrous oxide(N_(2)O),a potent greenhouse gas with a long-term global warming potential 298 times that of carbon *** phytochemicals or forages containing phytochemicals have shown the potential to improve the efficiency of nitrogen(N)utilization and decrease N_(2)O emissions from the excreta of *** inclusion of tannins can shift more of the excreted N to the feces,alter the urinary N composition and consequently reduce N_(2)O emissions from *** oils or saponins could inhibit rumen ammonia production and decrease urinary N *** grazed pastures,large amounts of glucosinolates or aucubin can be introduced into pasture soils when animals consume plants rich in these compounds and then excrete them or their metabolites in the urine or *** inhibitory compounds are excreted in the urine,they would be directly applied to the urine patch to reduce nitrification and subsequent N_(2)O *** phytochemicals’role in sustainable ruminant production is undeniable,but much uncertainty ***,transient effects,and adverse effects limit the effectiveness of these phytochemicals for reducing N *** this review,we will identify some current phytochemicals found in feed that have the potential to manipulate ruminant N excretion or mitigate N_(2)O production and deliberate the challenges and opportunities associated with using phytochemicals or forages rich in phytochemicals as dietary strategies for reducing N excretion and excreta-derived N_(2)O emissions.

关键词： Nitrogen metabolism Nitrous oxide Plant bioactive compounds Ruminant Urine patches

Variability Analysis for a Two-station Queueing Network in Heavy Traffic with Arrival Processes Driven by Queues

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 445-466页

作者： Jian CAO Yong-jiang GUO Kai-ming YANG School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China

The law of the iterated logarithm(LIL)for the performance measures of a two-station queueing network with arrivals modulated by independent queues is developed by a strong approximation *** convenience,two arrival processes modulated by queues comprise the external system,all others are belong to the internal *** is well known that the exogenous arrival has a great influence on the asymptotic variability of performance measures in *** the considered queueing network in heavy traffic,we get all the LILs for the queue length,workload,busy time,idle time and departure processes,and present them by some simple functions of the primitive *** LILs tell us some interesting insights,such as,the LILs of busy and idle times are zero and they reflect a small variability around their fluid approximations,the LIL of departure has nothing to do with the arrival process,both of the two phenomena well explain the service station’s situation of being busy all the *** external system shows us a distinguishing effect on the performance measures:an underloaded(overloaded,critically loaded)external system affects the internal system through its arrival(departure,arrival and departure together).In addition,we also get the strong approximation of the network as an auxiliary result.

关键词： two-station queueing network the law of the iterated logarithm(LIL) strong approximation fluid approximation