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Nano-scale Reinforcements and Properties of Al-Si-Cu Alloy Processed by High-Pressure Torsion

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1253-1259页

作者： dong Ying WU Siyuan HE Ziyang LIANG Chen cheng Feng HE Zuwei QIAN Chenhao School of Mechanical Engineering Jiangnan UniversityWuxi 214122China Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology Wuxi 214122China School of International Studies Renmin University of ChinaBeijing 100872China School of Engineering University of LiverpoolLiverpool L693GHUnited Kingdom

To improve the comprehensive mechanical properties of Al-Si-Cu alloy,it was treated by a high-pressure torsion process,and the effect of the deformation degree on the microstructure and properties of the Al-Si-Cu alloy was *** results show that the reinforcements(β-Si andθ-CuAl_(2)phases)of the Al-Si-Cu alloy are dispersed in theα-Al matrix phase with finer phase size after the *** processed samples exhibit grain sizes in the submicron or even nanometer range,which effectively improves the mechanical properties of the *** hardness and strength of the deformed alloy are both significantly raised to 268 HV and 390.04 MPa by 10 turns HPT process,and the fracture morphology shows that the material gradually transits from brittle to plastic before and after *** elements interdiffusion at the interface between the phases has also been effectively *** addition,it is found that the severe plastic deformation at room temperature induces a ternary eutectic reaction,resulting in the formation of ternary Al+Si+CuAl_(2)eutectic.

关键词： Al-Si-Cu alloy high-pressure torsion nano-scale reinforcements ternary eutectic

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Molecular origin for pH-responsive wormlike micelles of zwitterionic surfactants triggered by aromatic acid derivatives

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ChemPhysMater

ChemPhysMater 2024年第2期3卷 230-238页

作者： Shuo Lu Yonghang cheng Jinfeng dong Xuefeng Li Engineering Research Center of Organosilicon Compounds&Materials Ministry of EducationCollege of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072China

Introduction of aromatic acid derivatives(AADs)into zwitterionic surfactants is an efficient method to prepare wormlike micelles with pH-controllable viscosity;however,the coincident molecular origin of AAD/zwitterionic surfactant binary mixtures remains ***,the self-assembly of hydroxyl derivatives of benzoic acid(BA)and cetyldimethyl betaine(BS-16)mixtures in water was systematically assessed,and various factors,such as the molecular structure,molar ratio of AAD and BS-16,and solution pH,were *** structure-property relationship of AAD/BS-16 binary mixtures was established,which provided the molecular origin for the effect of AAD on micellar microstructures and the pH-induced morphological *** ortho-substituted hydroxyl moiety in the BA molecule facilitated the formation of larger wormlike micelles,whereas the effect of the meta-substituted moiety was less *** para-substituted hydroxyl moiety in BA did not favor micellar *** moiety exhibited similar characteristics to the increasing hydroxyl moiety number in the AAD molecules or solution pH where the negative effects of steric hindrance and electrostatic interactions of molecules in micelles aredominant.

关键词： Zwitterionic surfactants Aromatic acid derivatives pH response Wormlike micelles Spherical micelles Viscosity

Mold breakout prediction based on computer vision and machine learning

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Journal of Iron and Steel Research International 2024年第8期31卷 1947-1959页

作者： Yan-yu Wang Qi-can Wang Yong-chang Zhang Yong-hui cheng Man Yao Xu-dong Wang School of Materials Science and Engineering Dalian University of TechnologyDalian 116024LiaoningChina Key Laboratory of Solidification Control and Digital Preparation Technology Dalian University of TechnologyDalian 116024LiaoningChina

Breakout is the most serious production accident in continuous casting and must be detected and predicted by stable and reliable *** sticking region,which forms on the local copper plate and expanded into a"V"shape,is the typical precursor of ***,computer vision technology was exploited to visualize the temperature change rate of the copper plate based on the temperature signals from thermocouples;then,the static and dynamic features of the abnormal sticking region were ***,logistic regression and Adaboost models were used to study and identify these features,resulting in the development of a mold breakout prediction model based on computer vision and machine *** test results demonstrate that the proposed model can effectively distinguish anomalous temperature patterns and considerably reduce false alarms without any missing *** a result,the proposed method could offer valuable insights into the realm of abnormality detection and prediction during continuous casting process.

关键词： Abnormality detection Image processing Adaboost Logistic regression Continuous casting

Structure regulating of metal clusters in carbonized metallic organic frameworks for high-efficient microwave absorption via tuning interaction strength between metals and ligands

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Nano Research 2024年第3期17卷 1699-1709页

作者： Chang Sun Kun-Yan Zhao Ming-Lu Huang cheng-Long Luo Xu-dong Chen Ming Wang School of Chemistry and Chemical Engineering Chongqing Key Laboratory of Soft-Matter Material Chemistry and Function ManufacturingSouthwest UniversityChongqing 400715China Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory(Rongjiang Laboratory) Jieyang 515200China

Carbonized metallic organic frameworks(CMOF)have been attracting attention in microwave absorption(MA)research area because of their diverse structures,tunable compositions,and rich ***,structure regulation on metal clusters in CMOF is achieved by tuning the interaction strength between metals and ligands to enhance microwave absorption *** to relatively weak interaction among copper cations and ligands,copper nanoclusters(CuNC)can be uniformly formed and embedded within the cobalt/zinc(Co/Zn)***,copper cations are added to the Co/Zn bimetallic zeolitic imidazolate frameworks(ZIFs).Secondly,the CMOF composite particles with CuNCs(CuNCs/CoZn-CMOF)were developed by a pyrolysis *** CuNCs/CoZn-CMOF with an appropriate amount of CuNCs can harmonize both dielectric and magnetic *** a result,the minimum reflection loss(RLmin)reaches–45.1 dB at a matching thickness of 2.30 mm and the effective absorption bandwidth(EAB)is 8.80 GHz at a thickness of 3.10 *** broadband response to electromagnetic waves is attributed to interfacial polarization at CuNCs surface and heterogeneous interfaces,impedance matching and multiple scattering of electromagnetic *** study provides a feasible method to develop CMOF microwave absorption materials with high EAB values.

关键词： heterogeneous interface carbonized metallic organic frameworks microwave absorption interfacial polarization

Oilfield analogy and productivity prediction based on machine learning: Field cases in PL oilfield, China

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Petroleum Science 2024年第4期21卷 2554-2570页

作者： Wen-Peng Bai Shi-Qing cheng Xin-Yang Guo Yang Wang Qiao Guo Chao-dong Tan State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum (Beijing)

In the early time of oilfield development, insufficient production data and unclear understanding of oil production presented a challenge to reservoir engineers in devising effective development plans. To address this challenge, this study proposes a method using data mining technology to search for similar oil fields and predict well productivity. A query system of 135 analogy parameters is established based on geological and reservoir engineering research, and the weight values of these parameters are calculated using a data algorithm to establish an analogy system. The fuzzy matter-element algorithm is then used to calculate the similarity between oil fields, with fields having similarity greater than 70% identified as similar oil fields. Using similar oil fields as sample data, 8 important factors affecting well productivity are identified using the Pearson coefficient and mean decrease impurity（MDI） method. To establish productivity prediction models, linear regression（LR）, random forest regression（RF）, support vector regression（SVR）, backpropagation（BP）, extreme gradient boosting（XGBoost）, and light gradient boosting machine（Light GBM） algorithms are used. Their performance is evaluated using the coefficient of determination（R2）, explained variance score（EV）, mean squared error（MSE）, and mean absolute error（MAE） metrics. The Light GBM model is selected to predict the productivity of 30 wells in the PL field with an average error of only 6.31%, which significantly improves the accuracy of the productivity prediction and meets the application requirements in the field. Finally, a software platform integrating data query,oil field analogy, productivity prediction, and knowledge base is established to identify patterns in massive reservoir development data and provide valuable technical references for new reservoir development.

关键词： Data mining technique Analogy parameters Oilfield analogy Productivity prediction Software platform

Rheology of continental lithosphere and seismic anisotropy

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Science China Earth Sciences 2024年第1期67卷 31-60页

作者： Shengsi SUN Yunpeng dong Yixi LI Yihai YANG Chao cheng Bo HUI Bin ZHANG Rutao ZANG State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069China Shaanxi Earthquake Agency Xi’an 710068China

Rheology of rocks controls the deformation of the Earth at various space-time scales,which is crucial to understand the tectonic evolution of continental *** of rock rheology are mainly conducted via high-pressure and hightemperature rheological experiments and multi-scale observations and measurements of naturally deformed *** present,a large amount of data from such kinds of studies have been *** paper first provides an up-to-date comprehensive review of the rheological mechanisms,fabric types and seismic properties of the main rock-forming minerals at different depths of continental lithosphere,including olivine,orthopyroxene,clinopyroxene,amphibole,plagioclase,quartz and ***,progress in high-pressure and high-temperature experiments and natural deformation observations is introduced,mainly regarding the rheological strength and behavior,seismic velocity and anisotropy of lithospheric mantle peridotite,eclogite,mafic granulite,amphibolite and felsic ***,by taking the Tibetan Plateau as an example,the application of rock rheology for quantitative interpretation of seismic anisotropy data is *** combination of mineral deformation fabrics and seismic anisotropy is expected to make an important breakthrough in understanding the rheological properties and structure of continental lithosphere.

关键词： Lithosphere Mineral fabric Rheology Seismic velocity Anisotropy

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Thermoelectric Properties of an Indandione-Terminated Quinoidal Compound:Effect of the n-Type Dopants

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Chinese Journal of Chemistry 2024年第9期42卷 997-1003页

作者： Yingying Liu cheng Wang Tianzuo Wang Fei Jiao Shaoqiang dong Yunfeng Deng Yanhou Geng School of Materials Science and Engineering and Tianjin Key Laboratory of Molecular Optoelectronic Science Tianjin Universityand Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)Tianjin 300072China Institute of Molecular Aggregation Science Tianjin UniversityTianjin 300072China Tianjin Key Laboratory of Molecular Optoelectronic Science Department of ChemistrySchoolof ScienceTianjin UniversityTianjin300072China Joint Schoolof NationalUniversity of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New City FuzhouFujian350207China

The investigation of n-type doping holds a significant interest for the application of ***,the doping of an indandione-terminated compound Q-4F with a singlet open-shell ground state was studied using two n-dopants N-DMBI and *** of these two dopants can effectively dope Q-4F due to the large offset between the singly occupied molecular orbital(SOMO)of dopants and the lowest unoccupied molecular orbital(LUMO)of Q-4F.N-DMBI has a higher doping ability than LCV as demonstrated by the UV-vis-NIR and EPR ***,in comparison to N-DMBI doped Q-4F,LCV doped system exhibits much higher electrical conductivity and power factor due to its unperturbed molecular packing and favorable morphology after *** optimal conductivity of LCV doped Q-4F is 7.16×10^(-2)±0.16 S·cm^(-1) and the highest power factor reaches 12.3±0.85μW·m–1·K^(-2).These results demonstrate that the modulation of n-dopants is a powerful strategy to balance the doping efficiency and microstructure toward a maximum thermoelectric performance.

关键词： n-Doping Indandione Quinoidal compounds Organic thermoelectrics Electron transfer Organic electronics Energy conversion

Effects of the conversion of natural tropical rainforest to monoculture rubber plantations on soil hydrological processes

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JOURNAL OF PLANT ECOLOGY 2024年第2期17卷 122-133页

作者： Chen, Qiaoyan Fu, Ruiyu cheng, Siyuan Qiao, dong Hu, Zhongmin Zhang, Zijia Dai, Licong Hainan Univ Sch Ecol & Environm Hainan Baoting Trop Rainforest Ecosyst Observat & Haikou 570228 Peoples R China Hainan Univ Ctr Ecoenvironm Restorat Engn Hainan Prov Haikou 570228 Peoples R China Hainan Ecol Environm Monitoring Ctr Haikou Peoples R China

Rubber plantations have increased significantly under unprecedented economic growth in tropical areas, which leads to soil degradation and thereby alters soil hydrological processes. However, our understanding of how forest conversion affects soil hydrological processes remains unclear. Here, we collected soil samples from secondary forests (SF) and rubber plantations (RP) to determine the soil hydrological characteristics. We found the topsoil (0-20 cm) water retention in SF was higher than that of RP but displayed the contrast pattern in a deeper soil layer (20-60 cm). Meanwhile, the soil infiltration rates among the two vegetation types decreased significantly with infiltration time, with higher stable soil infiltration rates in SF than those in RP. Moreover, soil properties were also impacted by the forest conversion, such as the topsoil capillary porosity (CP) and total porosity (TP) in SF were higher than those of RP but contrasted in a deep soil layer. In comparison, the topsoil bulk density (BD) in SF was lower than that of RP, but contrasted in the deep soil layer and reached a significant level in the 0-10 and 40-50 cm (P < 0.05). Overall, the soil water retention was mainly determined by the CP, which could explain 31.56% of the total variance in soil water retention, followed by TP (26.57%) and soil BD (26.47%), whereas soil texture exerts a weak effect on soil water retention. Therefore, we can conclude that the conversion of tropical rainforest into rubber plantations may accelerate soil erosion owing to its lower topsoil water retention and soil infiltration rates.

关键词： soil water retention soil infiltration soil physicochemical properties rubber plantations secondary forest SATURATED HYDRAULIC CONDUCTIVITY BIODIVERSITY AGROFORESTRY LITTER

Hydrophobic tagging-induced degradation of NAMPT in leukemia cells

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Chinese Chemical Letters 2024年第9期35卷 214-218页

作者： Menglu Guo Ying-Qi Song Junfei cheng Guoqiang dong Xun Sun Chunquan Sheng Department of Natural Medicine School of PharmacyFudan UniversityShanghai 201203China School of Pharmaceutical Sciences Hainan UniversityHaikou 570228China School of Pharmacy Second Military Medical UniversityShanghai 200433China

Nicotinamide phosphoribosyl transferase(NAMPT)is considered as a promising target for cancer therapy to its crucial role in cancer *** the therapeutic potential of NAMPT enzymatic inhibitors,their effectiveness is limited by dose-related toxicity and the inability to suppress nonenzymatic functions of extracellular NAMPT(e NAMPT).Herein,we designed and synthesized the first hydrophobic tagging NAMPT *** them,compound NH-11 selectively degraded NAMPT in leukemia cells through the ubiquitin-proteasome *** NH-11 effectively induced apoptosis and showed low toxicity to normal cells,representing a promising anti-leukemia lead compound.?2024 Published by Elsevier *** behalf of Chinese Chemical Society and Institute of Materia Medica,Chinese Academy of Medical Sciences.

关键词： NAMPT Hydrophobic tagging Leukemia Degradation Anti-cancer

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