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International Journal of Minerals,Metallurgy and Materials 2020年第7期27卷 924-932页

作者： hai-yan Yu Xiao-lin pan Yong-pan Tian Gan-feng Tu School of Metallurgy Northeastern UniversityShenyang 110819China

The mineral transition and formation mechanism of calcium aluminate compounds in CaO-Al2O3-Na2O system during the hightemperature sintering process were systematically investigated using DSC-TG,XRD,SEM-EDS,FTIR,and Raman spectra,and the crystal structure of Na4Ca3(AlO2)10 was also simulated by Material Studio *** results indicated that the minerals formed during the sintering process included Na4Ca3(AlO2)10,CaO·Al2O3,and 12 CaO·7 Al2O3,and the content of Na4Ca3(AlO2)10 could reach 92 wt%when sintered at 1200°C for 30 *** main formation stage of Na4Ca3(AlO2)10 occurred at temperatures from 970 to 1100°C,and the content could reach82 wt%when the reaction temperature increased to 1100°*** crystal system of Na4Ca3(AlO2)10 was tetragonal,and the cells preferred to grow along crystal planes(110)and(210).The formation of Na4Ca3(AlO2)10 was an exothermic reaction that followed a secondary reaction model,and its activation energy was 223.97 kJ/mol.

关键词： calcium aluminate sodium oxide crystal structure formation kinetics sintering

Strength and ductility optimization of HPDC AlSi8MgCuZn2 alloys by modifying pre-aging treatment

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China Foundry 2024年第4期21卷 343-351页

作者： Yuan-hang Jiang Hui-ting Zheng Fei Liu hai-dong Zhao National Engineering Research Center of Near-net Shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510641China

Considering the components produced by high pressure die casting(HPDC)process usually with ultra-large sizes and complex morphologies,high temperature solid solution treatment is not a suitable method to further improve their mechanical *** this study,two-stage aging treatment with different pre-aging times was designed and employed to further improve the mechanical properties of HPDC Al8SiMgCuZn *** characteristics of precipitates were evaluated by a transmission electron microscope(TEM),and the precipitation strengthening mechanism was *** results reveal that the strengthening is mainly contributed by the precipitation ofβ″phase after two-stage aging,and the number density and size of the precipitates are significantly depended on the pre-aging *** number density of precipitates is increased with the pre-aging time prolonged from 0 h to 4 h,and then decreases with the further increase of pre-aging time from 4 h to 6 *** precipitates with the highest density and smallest size are observed after pre-aging for 4 *** pre-aged at 100℃for 4 h and then artificial aged at 200℃for 30 min,the yield strength of 207 MPa,ultimate tensile strength of 325 MPa and elongation of 7.6%are achieved.

关键词： high pressure die cast aluminum alloy microstructural heterogeneity mechanical properties precipitation strengthening two-stage aging

Online Sequential Extreme Multilayer Perception with Time Series Learning Machine Based Output Self Feedback for Prediction

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Journal of Shanghai Jiaotong university(Science) 2013年第3期18卷 366-375页

作者： pan Feng ZHAO hai-bo School of Information Science and Technology Donghua University Shanghai 200051 China Institude of Aircraft Equipment Naval Academy of Armament Shanghai 200436 China

This study presents a time series prediction model with output self feedback which is implemented based on online sequential extreme learning machine. The output variables derived from multilayer perception can feedback to the network input layer to create a temporal relation between the current node inputs and the lagged node outputs while overcoming the limitation of memory which is a vital port for any time-series prediction application. The model can overcome the static prediction problem with most time series prediction models and can effectively cope with the dynamic properties of time series data. A linear and a nonlinear forecasting algorithms based on online extreme learning machine are proposed to implement the output feedback forecasting model. They are both recursive estimator and have two distinct phases： Predict and Update. The proposed model was tested against different kinds of time series data and the results indicate that the model outperforms the original static model without feedback.

关键词： time series prediction extreme learning machine (ELM) autoregression (AR) online sequential learning ELM (OS-ELM) recurrent neural network (RNN)

Understanding Social Relationships with Person-Pair Relations

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Big Data Mining and Analytics 2022年第2期5卷 120-129页

作者： hang Zhao haicheng Chen Leilai Li hai Wan the Guizhou Post and Telecommunications Planning and Design Institute Co. Ltd.Guiyang 550003China School of Computer Science and Engineering Sun Yat-sen UniversityGuangzhou 510006China Ping An Technology(Shenzhen)Co. Ltd.Shenzhen 518049China

Social relationship understanding infers existing social relationships among individuals in a given scenario,which has been demonstrated to have a wide range of practical value in ***,existing methods infer the social relationship of each person pair in isolation,without considering the context-aware information for person pairs in the same *** context-aware information for person pairs exists extensively in reality,that is,the social relationships of different person pairs in a simple scenario are always related to each *** instance,if most of the person pairs in a simple scenario have the same social relationship,“friends”,then the other pairs have a high probability of being“friends”or other similar coarse-level relationships,such as“intimate”.This context-aware information should thus be considered in social relationship ***,this paper proposes a novel end-to-end trainable Person-Pair Relation Network(PPRN),which is a GRU-based graph inference network,to first extract the visual and position information as the person-pair feature information,then enable it to transfer on a fully-connected social graph,and finally utilizes different aggregators to collect different kinds of person-pair *** existing methods,the method—with its message passing mechanism in the graph model—can infer the social relationship of each person-pair in a joint way(i.e.,not in isolation).Extensive experiments on People In Social Context(PISC)-and People In Photo Album(PIPA)-relation datasets show the superiority of our method compared to other methods.

关键词： social relationship understanding person-pair relations Person-Pair Relation Network(PPRN)

Analysis on spectral gain characteristics of PPMgLN based quasi-phase-matching optical parametric amplification

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第4期10卷 601-606页

作者： hai-bin XU Bo WU Shuang-shuang CAI Yong-hang SHEN State Key Laboratory of Modern Optical Instrumentation Zhejiang University Hangzhou 310027 China

A deep understanding of the spectral gain characteristics of optical parametric oscillators (OPOs) and optical parametric amplifiers (OPAs) is important for a highly efficient optical parametric conversion. We numerically calculated the spectral gain characteristics of a quasi-phase-matching (QPM) parametric conversion process using the periodically poled 6% (mol/mol) MgO doped LiNbO3 (PPMgLN) as the nonlinear crystal. In the simulation we utilized the approach of a transformative matrix of the periodically poled nonlinear medium, which results from the small-signal approximation of three-wave mixed nonlinear equations. Numerical simulation results show that: (1) The full width at half maximum (FWHM) of the spectral gain of the parametric process becomes wider with the increase of parametric wavelength and reaches the maximum at degeneration; (2) The gain coefficient decreases gradually with the increase of parametric wavelength; (3) The spectral gain bandwidth decreases correspondingly with the increase of the nonlinear material length; (4) There exists an optimal parametric wavelength band, which is most suitable for the high gain parametric conversion when pumped by a laser source with a wide wavelength band, such as the high power fiber laser.

关键词： Spectral gain full width at half maximum (FWHM) Quasi-phase matching (QPM) Optical parametric conversion PPMgLN

Noteworthy phenomena in pediatric inherited cardiomyopathy

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World Journal of Pediatrics 2024年第6期20卷 635-637页

作者： Jin-hang Jiang Jie Tian Bo pan Department of Pediatric Cardiology National Clinical Key Cardiovascular SpecialtyNational Clinical Research Center for Child Health and DisordersMinistry of Education Key Laboratory of Child Development and DisordersChildren's Hospital of Chongqing Medical University136 Zhongshan Er RoadYuzhong DistirctChongqing 400014China Key Laboratory of Children's Important Organ Development and Diseases Chongqing Municipal Health CommissionChongqingChina

Pediatric cardiomyopathy has an early onset and poor ***,it was referred to as idiopathic cardiomyopathy due to unknown ***,recent advances in molecular genetics and molecular biology have demonstrated that most pediatric cardiomyopathy cases are related to genetic factors,mainly involving single gene and single nucleotide mutations[1,2].Although the pathogenicity of some gene mutations in patients has not been fully elucidated,genetic factors are still considered the main cause of pediatric cardiomyopathy.

关键词： cardiomyopathy pediatric etiology

Photocatalytic Degradation of Rhodamine B by Recyclable Ag Br/Polypyrrole(PPy)Nano-Catalysts

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Journal of Wuhan University of Technology(Materials Science) 2023年第5期38卷 1198-1204页

作者： YIN Xiaogang LIU Xinyun LI hang WU Huimin FU hai GONG Wei Key Laboratory of Functional Materials Chemistry of Gui Zhou Province School of Chemistry and Materials ScienceGui Zhou Normal UniversityGuiyang 550001China School of Pharmaceutical Sciences Guizhou Medical UniversityGuiyang 550025China

We investigated the removal of the organic dye rhodamine B in wastewater with recyclable AgBr/polypyrrole(PPy)*** PPy as an active base for electron transfer,and hexadecyltrimethylammonium bromide(CTAB)as both the soft-templating agent and the bromine source,a series of AgBr/PPy nano-photocatalysts containing various proportions of silver were prepared in a convenient one-step synthesis *** synthesized catalysts were characterized by TG analysis to reveal that,in comparison with pure PPy,the interaction between PPy and AgBr led to increased thermal *** combination of PPy and AgBr was observed through XRD and XPS *** the morphology study,the AgBr particles were found to be well dispersed in the PPy nanowire network from SEM *** the photodegradation experiments,up to 92%rhodamine B was degraded by the AgBr/PPy catalysts in the period of 1 hour under 254 nm UV *** catalysts could maintain 60%catalytic efficiency after 3 cycles in the recyclability test.

关键词： polypyrrole AgBr photocatalysts rhodamine B

Effect of AI_(2)O_(3)and MgO on crystallization and structure of Ca0-Si0_(2)-B_(2)0_(3)-based fluorine-free mold flux

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Journal of Iron and Steel Research International 2021年第5期28卷 552-562页

作者： Jun-yu Chen Wan-lin Wang Le-jun Zhou Zi-hang pan School of Metallurgy and Environment Central South UniversityChangsha 410083HunanChina National Center for International Cooperation of Clean Metallurgy Changsha 41(K)83HunanChina

The crytallization behavior and melt structure of the CaO-Si0^(2-)B20_(3)-based fluorine-free mold fux were *** results show that the crytallization of the mold fux was first inhibited and then promoted with the increase in Al_(2)0_(3) content from 4 to 12 wt.%.However,it was enhanced by MgO in the range of 2-10 wt.%.The results of Fourier transform infrared spectroscopy and Raman spectroscopy showed that Al_(2)0_(3) worked as a network former in the mold flux melt when its content was in the range of 4-8 wt.%,whereas it worked as the network breaker to provide 0^(2-)when its content was in the range of 8-12 wt.%.In addition,the combined efects from the charge compensation by Mg^(2+)and the network broken by 0^(2-)led to the increase in some typicalT-O-T(AI-O-A1,B-O-B,etc.,)and simpler structural units(Q^(2)(Si),B_^(O-)in the[B0_(2)0^(-)],.etc.)when the MgO content was in the range of 2-6 wt.%.The continuous increase in 0^(2-)provided by the addition of MgO from 6 to 10 wt.%further depolymerized the network of the melt and fnally caused fast crystallizationo.

关键词： Crystallization Single hot thermocouple technique Melt structure Fluorine-free mold flux

Ensemble projections of climate and streamflow in a typical basin of semi-arid steppes in Mongolian Plateau of 2021-2100

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Advances in Climate Change Research 2024年第2期15卷 230-243页

作者： hang pan Jian-Ping TANG Liang CHENG Man-Chun LI Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology Nanjing UniversityNanjing 210023China School of Geography and Ocean Science Nanjing UniversityNanjing 210023China Key Laboratory of Mesoscale Severe Weather/Ministry of Education Nanjing UniversityNanjing 210023China School of Atmospheric Sciences Nanjing UniversityNanjing 210023China

The Kherlen River is the main water source for Hulun Lake,the largest lake in northern *** to reduced inflow from the Kherlen River,Hulun Lake experienced rapid shrinkage at the beginning of the 21st century,posing a serious threat to the ecological security of northern ***,there is still a significant lack of projections regarding future climate change and its hydrological response in the Kherlen River *** study analyzed the projected climate and streamflow changes in the Kherlen River basin,a vital yet vulnerable international semi-arid steppes type basin.A combination of multi-model ensemble projection techniques,and the soil and water assessment tool(SWAT)model was employed to examine the spatio-temporal changes in precipitation,temperature,streamflow,and the associated uncertainties in the *** temperature(an increase of 1.84-6.42℃)and the precipitation(an increase of 15.0-46.0 mm)of Kherlen River basin are projected to increase by 2100,leading to a rise in streamflow(1.08-4.78 m^(3) s^(-1)).The upstream of the Kherlen River exhibits remarkable increasing trends in precipitation,which has a dominant influence on streamflow of Kherlen *** increases in streamflow are observed in April,August,September,and October compared to the reference period(1971-2000).These findings suggest a partial alleviation of water scarcity in the Kherlen River,but also an increased likelihood of hydrological extreme *** projected temperature increase in the Kherlen River basin exhibits the smallest uncertainty,while more pronounced uncertainties are found in precipitation and *** spread among the results of CMIP6 models is greater than that of CMIP5 models,with lower signal-to-noise ratio(SNR)values for temperature,precipitation,and streamflow.

关键词： Climate change Flow projection Uncertainty SWAT Mongolian Plateau

Electrochemically promoted N-heterocyclic carbene polymercatalyzed cycloaddition of aldehyde with isocyanide acetate

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Science China Chemistry 2022年第10期65卷 1873-1878页

作者： Chu-Hong Ou Ying-Ming pan hai-Tao Tang State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources School of Chemistry and Pharmaceutical Sciences of Guangxi Normal UniversityGuilin 541004China

N-heterocyclic carbene(NHC) is a potent organic small-molecule ***,its high synthetic price and frequent use in combination with excess oxidants have limited its utilization in industrial *** designed and synthesized a porous organic polymer with NHC as the core structure to solve the above *** catalytic performance of the polymer was tested in this *** polymer can successfully catalyze the cycloaddition reaction of aldehyde and ethyl isocyanoacetate under *** results showed that the polymer catalyst can be recycled and had higher catalytic activity than homogeneous *** developed catalytic system(organic electrochemistry and NHC polymer) solves the existing problems of NHC catalysis and provides a reference for the development of new green catalytic systems.

关键词： NHC catalysis electrochemistry heterogeneous catalysis cycloaddition

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