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Solidification behaviour and hot cracking susceptibility of a novel Ni-based superalloy

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Journal of Iron and Steel Research International 2024年第4期31卷 956-966页

作者： Yue Chen Shao-min Lv Xing-fei Xie Xiao-can wen Jng-long Qu Jin-hui Du High-Temperature Materials Institute China Iron and Steel Research Institute Group Co.Ltd.Beijing 100081China Beijing GAONA Materials and Technology Co. Ltd.Beijing 100081China Sichuan CISRI-GAONA Forging Co. Ltd.Deyang 610000SichuanChina

A novel Ni-based superalloy GH4151,with a γ′ volume fraction of about 55%and a service temperature capability up to 8oo oC,was *** to the different cooling conditions of various regions during the solidification of ingots,significant cooling rate variations may lead to the occurrence of hot *** scanning laser microscope was utilised to investigate the solidification process and phase precipitation behaviour of the GH4151 under wide range cooling *** characteristics of L→γ transformation were analysed,and the growth rates of at each stage were *** segregation behaviour was predicted using the Scheil equation,and the predicted results match well with the experimental *** sensitivity coefficient for hot cracking was modified,and cracking sensitivity coefficient values for the alloy under different cooling rates were computed,revealing that the alloy is most susceptible to hot cracking at 10℃/min cooling ***,controlling the cooling rate can reduce the possibility of hot cracking in ingot.

关键词： Ni-based superalloy Solidification behaviour In-situ observation Clyne and Davies's criterion:Hot cracking susceptibility

Formation of free-surface vortex and vortex suppression by rotating stopper-rod at end of tundish casting

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Journal of Iron and Steel Research International 2024年第5期31卷 1104-1116页

作者： Qing Fang Peng Zhao Hua Zhang wen-hao Zhou Gang Yu Jia-hui Wang Hong-wei Ni The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina Hunan Valin Xiangtan Iron and Steel Co. Ltd.Xiangtan411101HunanChina Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan430081HubeiChina

A rotating stopper-rod technique was proposed to suppress the formation of free-surface vortex in the *** large eddy simulation model coupled with volume of fluid model was developed to study the steel–slag–gas three-phase flow *** critical slag entrapment height of the free-surface vortex and mass of residual steel were predicted at different rotating speeds(30,60,90 and 120 r/min)of the rotating *** numerical model was verified by water model *** results showed that by rotating the stopper-rod in the opposite direction of the vortex above the submerged entry nozzle,the formation of vortex can be effectively disturbed and the critical height of the free-surface vortex can be *** for the 2nd strand,when the rotating speeds are 30,60,90 and 120 r/min,the critical height of the free-surface vortex above the 2nd strand is 7.3,4.7,6.3 and 7.4 cm,respectively.A reasonable rotating speed should be 60 r/min,which can reduce about 2 tons of residual *** rotating speeds just can reduce about 1.6 tons of residual steel.

关键词： Tundish Free-surface vortex Stopper-rod Numerical simulation Multiphase flow

MOF and its derivative materials modified lithium-sulfur battery separator:a new means to improve performance

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Rare Metals 2024年第6期43卷 2418-2443页

作者： Rong-Wei Huang yong-Qi Wang Dan You wen-Hao Yang Bin-Nan Deng Fei Wang Yue-Jin Zeng Yi-yong Zhang Xue Li National Local Joint Engineering Research Center for Lithium-Ion Batteries and Materials Preparation Technology Key Laboratory of Advanced Batteries Materials of Yunnan ProvinceFaculty of Metallurgical and Energy EngineeringKunming University of Science and TechnologyKunming 650093China State Key Laboratory of Physical Chemistry of Solid Surfaces Collaborative Innovation Centre of Chemistry for Energy MaterialsState-Province Joint Engineering Laboratory of Power Source Technology for New Energy VehicleEngineering Research Center of Electrochemical TechnologyMinistry of EducationCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

In recent years,lithium-sulfur batteries(LSBs)are considered as one of the most promising new generation energies with the advantages of high theoretical speeific capacity of sulfur(1675 mAh·g^(-1)),abundant sulfur resources,and environmental friendliness storage technologies,and they are receiving wide attention from the ***,the problems of the shuttle effect and lithium dendrite growth in LSBs have limited their practical application,so there is a need to find ways to solve these *** is an excellent choice to use novel materials to modify battery *** those novel materials,the metal-organic framework(MOF)has the properties of regular pores and controllable *** applied as a positive electrode and diaphragm,it can restrain the shuttle effect and lithium dendrite growth,especially since it shows excellent performance in diaphragm ***,various design strategies and synthesis methods of MOF-modified separators are reviewed in this paper,and the applications of MOF in LSBs separators in different forms are introduced,including the composite of MOF and carbon-based materials,the compounding of MOF and polymer,self-carbonization to form MOF-derived *** the same time,different characterization techniques are systematically reviewed to obtain the physical and chemical properties of MOF particles and the working mechanism of MOF-modified diaphragm,which provides a basis for further research in this ***,some future research trends and directions are put forward to fully tap the future commercial potential of MOF-modified diaphragm in LSBs.

关键词： MOF Lithium-sulfur battery Modified diaphragms Design strategies Prospect Characterization

Hepatic cystic lesions mimicking liver abscess on imaging: A report oftwo cases

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 86-89页

作者： Yun-wen Jiang yong-Hong Yu Tian-An Jiang Shu-Yuan Tian Department of Ultrasound Medicine Tongde Hospital of Zhejiang ProvinceHangzhou 310012China Department of Ultrasound Medicine the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

Hepatic cystic lesions include congenital dysplasia,inflammatory cystic lesions,neoplastic cystic lesions and parasitic cystic *** different treatment modalities can be chosen for these lesions,differential diagnosis is particularly important[1].Clinical features or imaging findings of cystic lesions of the liver are typical;for instance,liver abscess often shows thick-walled enhancement on contrast-enhanced CT.

关键词： lesions Hepatic cystic

Corrugated Graphene Paper Reinforced Silicone Resin Composite for Efficient Interface Thermal Management

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Chinese Journal of Polymer Science 2024年第7期42卷 1002-1014,I0010页

作者： Bo-wen Wang Heng Zhang Qing-Xia He hui-Tao Yu Meng-Meng Qin Wei Feng Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin300350China International Engineering Institute Tianjin UniversityTianjin300350China

With the rapid development of high-power-density electronic devices,interface thermal resistance has become a critical barrier for effective heat management in high-performance electronic ***,there is an urgent demand for advanced thermal interface materials(TIMs)with high cross-plane thermal conductivity and excellent compressibility to withstand increasingly complex operating *** achieve this aim,a promising strategy involves vertically arranging highly thermoconductive graphene on ***,with the currently available methods,achieving a balance between low interfacial thermal resistance,bidirectional high thermal conductivity,and large-scale production is ***,we prepared a graphene framework with continuous filler structures in in-plane and cross-plane directions by bonding corrugated graphene to planar graphene *** interface interaction between the graphene paper framework and polymer matrix was enhanced via surface functionalization to reduce the interface thermal *** resulting three-dimensional thermal framework endows the polymer composite material with a cross-plane thermal conductivity of 14.4 W·m^(-1)·K^(-1)and in-plane thermal conductivity of 130W·m^(-1)·K^(-1)when the thermal filler loading is 10.1 wt%,with a thermal conductivity enhancement per 1 wt%filler loading of 831%,outperforming various graphene structures as *** its high thermal conductivity,low contact thermal resistance,and low compressive modulus,the developed highly thermoconductive composite material demonstrates superior performance in TIM testing compared with TFLEX-700,an advanced commercial TIM,effectively solving the interfacial heat transfer issues in electronic *** novel filler structure framework also provides a solution for achieving a balance between efficient thermal management and ease of processing.

关键词： Graphene paper Vertically aligned structure Cross-plane thermal conductivity Low compressive modulus Thermal interface material

Preparation and Tribological Properties of Onion-like Carbon/Waterborne Polyurethane Coatings

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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 108-120页

作者： Fei Xingpeng Jiang Wuhao wen Maosheng Xu yong Hu Kunhong Hu Enzhu Department of Energy Materials and Chemical Engineering Hefei UniversityHefei 230601China Anhui Province Key Laboratory of Critical Friction Pair for Advanced Equipment Hefei 230088China

Rice husk powder was used as a carbon source in a high-temperature carbonization reaction for the production of rice husk ash(RHA).Under the catalysis of ferric nitrate,onion-like carbon(OLC)nanomaterial with a particle size of approximately 200 nm was successfully prepared and incorporated into waterborne polyurethane(WPU).The tribological properties of the coatings were determined using a controlled-atmosphere tribometer(WMT-2E)under dry-friction *** the friction test,the friction mechanism was investigated by characterizing the abrasive spot surfaces of the test samples using 3D laser microscopy and scanning electron microscopy/energy dispersive *** final results demonstrated that the thermal stability of WPU composite coatings containing various concentrations of OLC nanoparticles was significantly enhanced,binding forces between coatings and steel sheets increased,and hardness improved compared to pure WPU *** tests revealed a notable enhancement in the anti-wear properties of WPU coatings due to the presence of OLC ***,the wear rate of the 1.5%OLC/WPU coating was reduced by 45.3%.The coating’s anti-wear mechanism was attributed to the improvement in the mechanical properties of WPU due to OLC,as well as OLC’s participation in the formation of a transfer film under induced friction,which protected the matrix.

关键词： biomass carbon onion-like carbon waterborne polyurethane wear transfer films

Automatic velocity picking based on optimal key points tracking algorithm

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Petroleum Science 2024年第2期21卷 903-917页

作者： yong-Hao Wang wen-Kai Lu Song-Bai Jin Yang Li Yu-Xuan Li Xiao-Feng Gu The Institute for Artificial Intelligence(THUAI) Tsinghua UniversityBeijing100084China State Key Laboratory of Intelligent Technology and Systems Tsinghua UniversityBeijing100084China Beijing National Research Center for Information Science and Technology(BNRist) Beijing100084China The Department of Automation Tsinghua UniversityBeijing100084China

Picking velocities from semblances manually is laborious and necessitates experience. Although various methods for automatic velocity picking have been developed, there remains a challenge in efficiently incorporating information from nearby gathers to ensure picked velocity aligns with seismic horizons while also improving picking accuracy. The conventional method of velocity picking from a semblance volume is computationally demanding, highlighting a need for a more efficient strategy. In this study, we introduce a novel method for automatic velocity picking based on multi-object tracking. This dynamic tracking process across different semblance panels can integrate information from nearby gathers effectively while maintaining computational efficiency. First, we employ accelerated density clustering on the velocity spectrum to discern cluster centers without the requirement for prior knowledge regarding the number of clusters. These cluster centers embody the maximum likelihood velocities of the main subsurface structures. Second, our proposed method tracks key points within the semblance volume. Kalman filter is adopted to adjust the tracking process, followed by interpolation on these tracked points to construct the final velocity model. Our synthetic data example demonstrates that our proposed algorithm can effectively rectify the picking errors of the clustering algorithm. We further compare the performances of the clustering method(CM), the proposed tracking method(TM), and the variational method(VM) on a field dataset from the Gulf of Mexico. The results attest that our method offers superior accuracy than CM, achieves comparable accuracy with VM, and benefits from a reduced computational cost.

关键词： Velocity picking Multi-object tracking Density clustering Kalman filter

A 3D-printed microhemispherical shell resonator with electrostatic tuning for a Coriolis vibratory gyroscope

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Microsystems & Nanoengineering 2024年第2期10卷 25-35页

作者： Baoyin Hou Ye Zhu Chaofan He Weidong Wang Zhi Ding wen He yong He Lufeng Che College of Information Science and Electronic Engineering Zhejiang UniversityHangzhou310027China Center for Microelectronics Shaoxing InstituteZhejiang UniversityShaoxing312035China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou310058China School of Mechanical Engineering Zhejiang UniversityHangzhou310058China

The emergence of microhemispherical resonant gyroscopes,which integrate the advantages of exceptional stability and long lifetime with miniaturization,has afforded new possibilities for the development of whole-angle ***,existing methods used for manufacturing microhemispherical resonant gyroscopes based on MEMS technology face the primary drawback of intricate and costly ***,we report the design,fabrication,and characterization of the first 3D-printable microhemispherical shell resonator for a Coriolis vibrating *** remarkably achieve fabrication in just two steps bypassing the dozen or so steps required in traditional *** utilizing the intricate shaping capability and ultrahigh precision offered by projection microstereolithography,we fabricate 3D high-aspect-ratio resonant structures and controllable capacitive air gaps,both of which are extremely difficult to obtain via MEMS *** addition,the resonance frequency of the fabricated resonators can be tuned by electrostatic forces,and the fabricated resonators exhibit a higher quality factor in air than do typical MEMS microhemispherical *** work demonstrates the feasibility of rapidly batch-manufacturing microhemispherical shell resonators,paving the way for the development of microhemispherical resonator gyroscopes for portable inertial ***,this particular design concept could be further applied to increase uptake of resonator tools in the MEMS community.

关键词： resonator tuning electrostatic

Long noncoding RNAs HAND2-AS1 ultrasound microbubbles suppress hepatocellular carcinoma progression by regulating the miR-873-5p/tissue inhibitor of matrix metalloproteinase-2 axis

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1547-1563页

作者： Qiang Zou Hao-wen Wang Xi-Liang Di Yuan Li hui Gao Department of Interventional Therapy Tianjin Medical University Cancer Institute and HospitalTianjin 300060China National Clinical Research Center for Cancer Key Laboratory of Cancer Prevention and TherapyTianjin’s Clinical Research Center for CancerTianjin 300060China College of Animal Science and Technology Northeast Agricultural UniversityHarbin 150030Heilongjiang ProvinceChina Department of Hematology and Oncology Linyi People’s HospitalLinyi 251500Shandong ProvinceChina Department of Comprehensive Oncology Baotou Cancer HospitalBaotou 014030Inner Mongolia Autonomous RegionChina

BACKGROUND Increasing data indicated that long noncoding RNAs(lncRNAs)were directly or indirectly involved in the occurrence and development of tumors,including hepatocellular carcinoma(HCC).Recent studies had found that the expression of lncRNA HAND2-AS1 was downregulated in HCC tissues,but its role in HCC progression is *** targeted microbubble destruction mediated gene transfection is a new method to overexpress *** To study the role of ultrasound microbubbles(UTMBs)mediated HAND2-AS1 in the progression of HCC,in order to provide a new reference for the treatment of *** In vitro,we transfected HAND2-AS1 siRNA into HepG2 cells by UTMBs,and detected cell proliferation,apoptosis,invasion and epithelial-mesenchymal transition(EMT)by cell counting kit-8 assay,flow cytometry,Transwell invasion assay and Western blotting,*** addition,we transfected miR-837-5p mimic into UTMBs treated cells and observed the changes of cell ***,the UTMBs treated HepG2 cells were transfected together with miR-837-5p mimic and tissue inhibitor of matrix metalloproteinase-2(TIMP2)overexpression vector,and we detected cell proliferation,apoptosis,invasion and *** vivo,we established a mouse model of subcutaneous transplantation of HepG2 cells and observed the effect of HAND2-AS1 silencing on tumor formation *** We found that UTMBs carrying HAND2-AS1 restricted cell proliferation,invasion,and EMT,encouraged apoptosis,and HAND2-AS1 silencing eliminated the effect of ***,miR-873-5p targets the gene HAND2-AS1,which also targets the 3’UTR of *** miR-873-5p mimic counteracted the impact of ***,miR-873-5p mimic solely or in combination with pcDNA-TIMP2 had been transformed into HepG2 cells exposed to *** discovered that TIMP2 reversed the effect of miR-873-5p mimic caused by the blocked signalling cascade for matrix metalloproteinase(MMP)2/*** vivo results showed that HAND2-AS1 silencing sig

关键词： Hepatocellular carcinoma Ultrasound microbubbles Long noncoding RNA HAND2-AS1 miR-873-5p Tissue inhibitor of matrix metalloproteinase-2