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Effect of ultrasonic field on microstructure and mechanical properties of as-cast 7085 aluminum alloy

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Journal of Central South University 2018年第6期25卷 1285-1294页

作者： ZOU Hao PAN Qing-lin Sill Yun-jia CHEN ling XIANG Hao li rui-shi li Hang School of Materials Science and Engineering Central South UniversityChangsha 410083China Suntown Technology Group Co. LtdChangsha 410200China ~ Central South University Press and Springer-Verlag GmbH Germanypart of Springer Nature 20 l 8

The effect of an ultrasonic field on the microstructure and mechanical properties of 7085 aluminum alloy during solidification was investigated by optical microscopy, Vickers hardness test, tensile test, scanning electron microscopy （SEM） with energy dispersive X-ray spectrometry, and electron probe micro-analysis （EPMA）. The results showed that the grains of aluminum alloy were significantly refined and secondary phases were dispersed and distributed uniformly at the grain boundaries, due to ultrasonic treatment （UST）. By EPMA, it was observed that the distribution of the main elements A1, Zn, Mg and Cu was more homogeneous in alloys with UST, than in alloys without UST. The mechanical properties of the aluminum alloy also significantly improved. As demonstrated by the SEM fractography of the fractured faces of several castings, fracture of the unrefined specimens occurred in a brittle manner, whereas the cracks of the refined specimens showed quasi-cleavage fracture.

关键词： ultrasonic treatment grain refinement microstructure secondary phases

Joint Feature Encoding and Task Alignment Mechanism for Emotion-Cause Pair Extraction

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Computers, Materials & Continua 2025年第1期82卷 1069-1086页

作者： shi li Didi Sun College of Computer and Control Engineering Northeast Forestry UniversityHarbin150040China

With the rapid expansion of social media,analyzing emotions and their causes in texts has gained significant ***-cause pair extraction enables the identification of causal relationships between emotions and their triggers within a text,facilitating a deeper understanding of expressed sentiments and their underlying *** comprehension is crucial for making informed strategic decisions in various business and societal ***,recent research approaches employing multi-task learning frameworks for modeling often face challenges such as the inability to simultaneouslymodel extracted features and their interactions,or inconsistencies in label prediction between emotion-cause pair extraction and independent assistant tasks like emotion and cause *** address these issues,this study proposes an emotion-cause pair extraction methodology that incorporates joint feature encoding and task alignment *** model consists of two primary components:First,joint feature encoding simultaneously generates features for emotion-cause pairs and clauses,enhancing feature interactions between emotion clauses,cause clauses,and emotion-cause ***,the task alignment technique is applied to reduce the labeling distance between emotion-cause pair extraction and the two assistant tasks,capturing deep semantic information interactions among *** proposed method is evaluated on a Chinese benchmark corpus using 10-fold cross-validation,assessing key performance metrics such as precision,recall,and F1 *** results demonstrate that the model achieves an F1 score of 76.05%,surpassing the state-of-the-art by 1.03%.The proposed model exhibits significant improvements in emotion-cause pair extraction(ECPE)and cause extraction(CE)compared to existing methods,validating its *** research introduces a novel approach based on joint feature encoding and task alignment mechanisms,contributing to advancements in emotion-c

关键词： Emotion-cause pair extraction interactive information enhancement joint feature encoding label consistency task alignment mechanisms

Interpretable Machine Learning Method for Compressive Strength Prediction and Analysis of Pure Fly Ash-based Geopolymer Concrete

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 65-78页

作者： shi Yuqiong li Jingyi ZHANG Yang li li Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas of Ministry of Education Northwest A&F Uni-versityYangling 712100China College of Water Resources and Architectural Engineering Northwest A&F UniversityYangling 712100China Chongqing Key Laboratory of Public Big Data Security Technology Chongqing 401420China Chongqing College of Mobile Communication Chongqing 401520China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina National Rail Transit Electrification and Automation Engineering Technology Research Center(Hong Kong Branch) The Hong Kong Polytechnic UniversityKowloonHung HomHong KongChina

In order to study the characteristics of pure fly ash-based geopolymer concrete(PFGC)conveniently,we used a machine learning method that can quantify the perception of characteristics to predict its compressive *** this study,505 groups of data were collected,and a new database of compressive strength of PFGC was *** order to establish an accurate prediction model of compressive strength,five different types of machine learning networks were used for comparative *** five machine learning models all showed good compressive strength prediction performance on *** them,R2,MSE,RMSE and MAE of decision tree model(DT)are 0.99,1.58,1.25,and 0.25,*** R2,MSE,RMSE and MAE of random forest model(RF)are 0.97,5.17,2.27 and 1.38,*** two models have high prediction accuracy and outstanding generalization *** order to enhance the interpretability of model decision-making,we used importance ranking to obtain the perception of machine learning model to 13 *** 13 variables include chemical composition of fly ash(SiO_(2)/Al_(2)O_(3),Si/Al),the ratio of alkaline liquid to the binder,curing temperature,curing durations inside oven,fly ash dosage,fine aggregate dosage,coarse aggregate dosage,extra water dosage and sodium hydroxide *** temperature,specimen ages and curing durations inside oven have the greatest influence on the prediction results,indicating that curing conditions have more prominent influence on the compressive strength of PFGC than ordinary Portland cement *** importance of curing conditions of PFGC even exceeds that of the concrete mix proportion,due to the low reactivity of pure fly ash.

关键词： machine learning pure fly ash geopolymer compressive strength feature perception

3D Reconstruction by Kinect Sensor:A Brief Review

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Computer Aided Drafting,Design and Manufacturing 2014年第1期24卷 1-11页

作者： li shi-rui TAO Ke-lu WANG Si-yuan li Hai-yang CAO Wei-guo li Hua Key Laboratory of Intelligent Information Processing Institute of Computing Technology Chinese Academy of Sciences University of Chinese Academy of Sciences

While Kinect was originally designed as a motion sensing input device of the gaming console Microsoft Xbox 360 for gaming purposes, it＇s easy-to-use, low-cost, reliability, speed of the depth measurement and relatively high quality of depth measurement make it can be used for 3D reconstruction. It could make 3D scanning technology more accessible to everyday users and turn 3D reconstruction models into much widely used asset for many applications. In this paper, we focus on Kinect 3D reconstruction.

关键词： Kinect 3D reconstruction RGBD

The evaluation of aprotinin contained preservation solution with a new animal model

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医学信息（手术学分册） 2008年第11期21卷 963-966页

作者： FU Qing -lin ZHANG Xin - zhong HAN Pei - li shi rui -feng Psstdoctor Station the First Affiliated Hospital of Xinxiang Medical University Weihui 453100 Henan Province China

ObjectiveTo explore the protective effect of aprotinin contained LPD (low potassium dextran) solution via an in situ rabbit lung preservation *** New Zealand rabbits were divided randomly into 3 groups,10 in each *** group A (control group),the left lung hilus was clamped without solution perfusion;In group B (LPD group) and group C (aprotinin group),the lungs were perfused with LPD solution and aprotinin contained LPD,*** lungs in all groups were stored at 10 centigrade in a specially made lung preservation container for 2 hours and then unclamped the lung hilus to reperfuse the lung for 2 *** venous blood samples were collected at pre-clamping of lung hilus,5 minutes and 120 minutes after reperfusion for analysis of blood *** of lung tissue was excised for morphological examination at pre-unclamping of lung hilus and 2 hours after *** of bronchoalveolar lavage fluid was taken for the evaluation of inflammation *** venous partial pressure of oxygen (PvPO2) in the 3 groups at 5 minutes and 120 minutes after reperfusion were significantly higher than those before clamping of lung hilus,***2 in group A and group B at 120 minutes after reperfusion were significantly higher than those at 5 minutes after *** was no significant difference of PvPO2 in group C between 5 minutes and 120 minutes after ***2 in group C at 5 minutes and 120 minutes after reperfusion were significantly higher than those in group A and group *** morphological lesion was more severe in group A and B than that in group *** PMN percentage in bronchoalveolar lavage fluid in group A and B was significantly higher than that in group *** protective effect of aprotinin is obvious for lung protection in animal *** contained lung preservation solution is superior to LPD for lung protection.

关键词：肺移植静脉注射患者临床分析

反应堆时空动力学蒙特卡罗改进准静态方法研究

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原子能科学技术 2013年第B6期47卷 275-279页

作者：徐琪王侃李世锐余纲林清华大学工程物理系北京100084

改进准静态方法可采用大时间步,减少反应堆时空动力学问题的计算耗时。本文提出了蒙特卡罗改进准静态方法,将两种方法的优势结合,用于新型反应堆的时空动力学问题。基于改进准静态方法的理论框架,研究设计了伴随通量统计、动态参数统计... 详细信息

改进准静态方法可采用大时间步,减少反应堆时空动力学问题的计算耗时。本文提出了蒙特卡罗改进准静态方法,将两种方法的优势结合,用于新型反应堆的时空动力学问题。基于改进准静态方法的理论框架,研究设计了伴随通量统计、动态参数统计和形状函数计算等相应的蒙特卡罗算法。针对一维两群问题,实现了相应的算法。与确定论程序计算结果的比较表明,蒙特卡罗改进准静态方法是可行的。

关键词：时空动力学改进准静态方法蒙特卡罗方法

Low-temperature chlorination roasting technology for the simultaneous recovery of valuable metals from spent liCoO_(2)cathode material

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 80-91页

作者： Junjie shi Changle Hou Jingjing Dong Dong Chen Jianzhong li Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China

With the continuous increase in the disposal volume of spent lithium-ion batteries(liBs),properly recycling spent liBs has become essential for the advancement of the circular *** study presents a systematic analysis of the chlorination roasting kinetics and proposes a new two-step chlorination roasting process that integrates thermodynamics for the recycling of liB cathode *** activation energy for the chloride reaction was 88.41 kJ/mol according to thermogravimetric analysis–derivative thermogravimetry data obtained by using model-free,model-fitting,and Z(α)function(αis conversion rate).Results indicated that the reaction was dominated by the first-order(F1)model when the conversion rate was less than or equal to 0.5 and shifted to the second-order(F2)model when the conversion rate exceeded *** conditions were determined by thoroughly investigating the effects of roasting temperature,roasting time,and the mass ratio of NH_(4)Cl to liCoO_(2).Under the optimal conditions,namely 400℃,20 min,and NH_(4)Cl/liCoO_(2)mass ratio of 3:1,the leaching efficiency of li and Co reached 99.43% and 99.05%,*** of the roasted products revealed that valuable metals in liCoO_(2)transformed into CoCl_(2) and ***,the reaction mechanism was elucidated,providing insights for the establishment of a novel low-temperature chlorination roasting technology based on a crystal structure *** technology can guide the development of liB recycling processes with low energy consumption,low secondary pollution,high recovery efficiency,and high added value.

关键词： spent lithium-ion battery thermodynamics chlorination roasting kinetics circular economy

Effect of pyrite content on chalcopyrite flotation under different regrinding conditions

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 49-57页

作者： Zejun Wang Qing shi Guofan Zhang Yuxuan Zhu Binbin li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha 410083China

This study aimed to investigate the effect of varying pyrite(Py)content on copper(Cu)in the presence of different regrinding conditions,which were altered using different types of grinding media:iron,ceramic balls,and their mixture,followed by flotation in the cleaner *** flotation performance of rough Cu concentrate can be improved by changing the regrinding conditions based on the Py *** electron microscopy,X-ray spectrometry,ethylenediaminetetraacetic acid disodium salt extraction,and X-ray photoelectron spectroscopy studies illustrated that when the Py content was high,the use of iron media in regrinding promoted the generation of hydrophilic Fe OOH on the surface of Py and improved the Cu *** ceramic medium with a low Py content prevented excessive Fe OOH from covering the surface of chalcopyrite(Cpy).Electrochemical studies further showed that the galvanic corrosion current of Cpy-Py increased with the addition of Py and became stronger with the participation of iron media.

关键词： chalcopyrite regrinding media pyrite galvanic corrosion flotation

Experimental Study on Diesel Spray and Flame Asymmetry Characteristics of Dual-Orifice Nozzles for a Medium-Speed Engine

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Journal of Thermal Science 2025年第1期34卷 303-322页

作者： JU Dehao liU rui ZHENG liang DENG Jiahui ZHANG Wenzheng HUO Jinlu HUANG li Shanghai Marine Diesel Engine Research Institute National Key Laboratory of Marine Engine Science and Technology Key Laboratory for Power Machinery and Engineering Ministry of EducationShanghai Jiao Tong University

The asymmetry of the multi-orifice spray will cause uneven heat load of the marine diesel engine,thereby affecting its working performance and service ***,an in-depth understanding of the spray and flame characteristics of multi-orifice nozzles will guide the optimization of the nozzle structure,needle design and diesel atomization and combustion *** this reason,four groups of dual-orifice nozzles with different hole diameters(0.1-0.55 mm) and mass flow rates covering the typical marine medium-speed diesel injections are designed and customized,and the constant volume chamber(CVC) with high temperature and pressure is used to simulate the actual in-cylinder working conditions of the diesel engine for the spray visualization *** study the asymmetry of the fuel sprays discharged from a diesel injector,the multi-orifice nozzle is simplified as a dual-orifice nozzle in this *** with X-ray Computed Tomography(CT) imaging technology,the influences of the nozzle internal structure on the spray and flame asymmetry are studied in the constructed supercritical *** is found that the asymmetry of the inlet angle and the equivalent length-diameter ratio is positively correlated with the inconsistency of the dual *** an increase in the injection pressure and nozzle diameter,the asymmetry of the dual spray becomes more pronounced,resulting in greater disparities in the ignition delay times and ignition positions of the two ***,the increase in nozzle diameter also leads to combustion instability,resulting in a flame with a serrated *** the increase of ambient temperature,the proportion of liquid phase in the jet decreases and the relative density of spray front decreases.

关键词： atomization dual-orifice nozzle nozzle structure spray flame asymmetry