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Study on the Application of Refined Nursing Care in The Care for Elderly Patients with Reflux Esophagitis 被引量:1
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作者 Zhe Chen Rui Cao 《Journal of Clinical and Nursing Research》 2024年第4期69-72,共4页
Objective: To investigate the application effect of refined nursing care in the care for elderly patients with reflux esophagitis. Methods: Following the difference in nursing style, 84 cases of elderly patients with ... Objective: To investigate the application effect of refined nursing care in the care for elderly patients with reflux esophagitis. Methods: Following the difference in nursing style, 84 cases of elderly patients with reflux esophagitis admitted to our hospital from May 2022 to May 2023 were randomly grouped into a control group and a research group, with 42 cases each. The control group was given conventional nursing care and the research group was given refined nursing care. The psychological state and treatment adherence of the two groups of patients after the nursing intervention were compared. Results: After the nursing intervention, the self-rating anxiety scale (SAS) and self-rating depression scale (SDS) scores of the research group were lower than those of the control group (P < 0.05). The treatment compliance of the research group was better than the control group (P < 0.05). Conclusion: The implementation of refined nursing care for elderly patients with reflux esophagitis exhibited a significant effect on improving the patient’s psychological state, treatment compliance, and rehabilitation. 展开更多
关键词 Geriatric reflux esophagitis refined nursing care Application research
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Evaluation of the Impact of Refined Quality Control Management Model on the Qualified Rate of Disinfection and Sterilization of Surgical Instruments in the Sterilization Supply Center 被引量:1
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作者 Qin Liu 《Journal of Clinical and Nursing Research》 2024年第1期168-173,共6页
Objective:To evaluate the application value of a refined quality control management model for a sterilization supply center.Methods:A retrospective analysis was conducted on the work situation of the sterilization sup... Objective:To evaluate the application value of a refined quality control management model for a sterilization supply center.Methods:A retrospective analysis was conducted on the work situation of the sterilization supply center from January 2021 to January 2023.The work situation before January 31,2022,was classified as the control group;a routine quality control management model was implemented,and the work situation after January 31,2022,was classified as the observation group.The quality of medical device management and department satisfaction between the two groups were compared.Results:The timely recovery and supply rate,classification and cleaning pass rate,disinfection pass rate,packaging pass rate,sterilization pass rate,and department satisfaction score in the observation group were all higher than those of the control group(P<0.05).Conclusion:Implementing a refined quality control management model in the sterilization supply center can improve the quality management level of medical devices and department satisfaction and is worthy of promotion. 展开更多
关键词 refined quality control management model Sterilization supply center Disinfection and sterilization pass rate
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Refined Anam-Net:Lightweight Deep Learning Model for Improved Segmentation Performance of Optic Cup and Disc for Glaucoma Diagnosis
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作者 Khursheed Aurangzeb Syed Irtaza Haider Musaed Alhussein 《Computers, Materials & Continua》 SCIE EI 2024年第7期1381-1405,共25页
In this work,we aim to introduce some modifications to the Anam-Net deep neural network(DNN)model for segmenting optic cup(OC)and optic disc(OD)in retinal fundus images to estimate the cup-to-disc ratio(CDR).The CDR i... In this work,we aim to introduce some modifications to the Anam-Net deep neural network(DNN)model for segmenting optic cup(OC)and optic disc(OD)in retinal fundus images to estimate the cup-to-disc ratio(CDR).The CDR is a reliable measure for the early diagnosis of Glaucoma.In this study,we developed a lightweight DNN model for OC and OD segmentation in retinal fundus images.Our DNN model is based on modifications to Anam-Net,incorporating an anamorphic depth embedding block.To reduce computational complexity,we employ a fixed filter size for all convolution layers in the encoder and decoder stages as the network deepens.This modification significantly reduces the number of trainable parameters,making the model lightweight and suitable for resource-constrained applications.We evaluate the performance of the developed model using two publicly available retinal image databases,namely RIM-ONE and Drishti-GS.The results demonstrate promising OC segmentation performance across most standard evaluation metrics while achieving analogous results for OD segmentation.We used two retinal fundus image databases named RIM-ONE and Drishti-GS that contained 159 images and 101 retinal images,respectively.For OD segmentation using the RIM-ONE we obtain an f1-score(F1),Jaccard coefficient(JC),and overlapping error(OE)of 0.950,0.9219,and 0.0781,respectively.Similarly,for OC segmentation using the same databases,we achieve scores of 0.8481(F1),0.7428(JC),and 0.2572(OE).Based on these experimental results and the significantly lower number of trainable parameters,we conclude that the developed model is highly suitable for the early diagnosis of glaucoma by accurately estimating the CDR. 展开更多
关键词 refined Anam-Net parameter tuning deep learning optic cup optic disc cup-to-disc ratio glaucoma diagnosis
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Long-term Development Prospects and Suggestions for Domestic Refined Oil Market
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作者 Kong Jingyuan Qin Biao Li Mingjiang 《China Oil & Gas》 CAS 2024年第4期30-39,共10页
Over the past decade,China’s refined oil market has experienced considerable growth and fluctuations.Gasoline consumption has generally followed the growth rate of vehicle equipment,with fluctuations influenced by tr... Over the past decade,China’s refined oil market has experienced considerable growth and fluctuations.Gasoline consumption has generally followed the growth rate of vehicle equipment,with fluctuations influenced by travel frequency;aviation fuel consumption has seen stable growth following the end of COVID-19,while diesel consumption has been affected by multiple factors including demand and policy.With the rapid development of new energy vehicles and alternative fuels,the gasoline and diesel market has essentially peaked,yet domestic production of refined oil continues to grow,leading to an increasingly prominent oversupply issue.To achieve the dual carbon goals,the Chinese government has introduced a series of policies that have a profound impact on the refined oil market.Facing resource surplus and market demand changes,the refining industry needs to optimize production capacity structure,and oil products retail companies face transformation pressure.The article aims to provide market analysis and recommendations,serving as a reference for relevant enterprises and policymakers. 展开更多
关键词 COMPANIES refined AVIATION
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Impact of early refined nursing program on prognosis of middleaged and elderly patients with cognitive dysfunction combined with cerebral infarction
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作者 Hui-Lian Xiong Zhi-Xin Li +2 位作者 Xin Lu Yan-Hua Lu Ping Zhong 《World Journal of Psychiatry》 SCIE 2024年第7期1034-1042,共9页
BACKGROUND Cerebral infarction is a local or extensive necrosis of brain tissue.Subsequently,the corresponding neurological deficits appear.The incidence of cerebrovascular diseases in China is increasing gradually.Af... BACKGROUND Cerebral infarction is a local or extensive necrosis of brain tissue.Subsequently,the corresponding neurological deficits appear.The incidence of cerebrovascular diseases in China is increasing gradually.After the onset of cerebrovascular disease,the most common sequelae include movement disorders,language disorders,and cognitive dysfunction.AIM To investigate the effect of early refined nursing program on the prognosis of middle-aged and elderly patients with cerebral infarction combined with cognitive dysfunction.METHODS A retrospective study was conducted to divide 60 patients with cerebral infarction and cognitive impairment into an experimental group(n=32)and a control group(n=28).The experimental group received early intensive care every day,and the control group received daily routine care.The scores of the Mini-Mental State Examination(MMSE)and the Trail Making Test(TMT),as well as the latency and amplitude of the event-related potential P300,were used as main indicators to evaluate changes in cognitive function,and changes in BDNF,TGF-β,and GDNF expression were used as secondary indicators.RESULTS Both groups experienced notable enhancements in MMSE scores,with the experi-mental group demonstrating higher scores than the control group(experimental:28.75±2.31;control:25.84±2.87).Moreover,reductions in TMT-A and TMT-B scores were observed in both groups(experimental:TMT-A 52.36±6.18,TMT-B 98.47±10.23;control:TMT-A 61.48±7.92,TMT-B 112.63±12.55),with the experimental group displaying lower scores.P300 Latency decreased(experimental:270.63 ms±14.28 ms;control:285.72 ms±16.45 ms),while amplitude increased(experimental:7.82μV±1.05μV;control:6.35μV±0.98μV)significantly in both groups,with superior outcomes in the experimental cohort.Additionally,the levels of the growth factors BDNF,TGF-β1,and GDNF surged(experimental:BDNF 48.37 ng/mL±5.62 ng/mL,TGF-β152.14 pg/mL±4.28 pg/mL,GDNF 34.76 ng/mL±3.89 ng/mL;control:BDNF 42.58 ng/mL±4.73 ng/mL,TGF-β146.23 pg/mL±3.94 pg/mL,GDNF 30.25 ng/mL±2.98 ng/mL)in both groups,with higher levels in the experimental group.CONCLUSION For middle-aged and elderly patients with cerebral infarction and cognitive dysfunction,early refined nursing can significantly improve their cognitive function and prognosis. 展开更多
关键词 Early refined nursing program Cerebral infraction Cognitive impairment PSYCHIATRY Trajectory test
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From“Car Priority”to“People Priority”: Exploring New Ideas for Refined Road Space Design
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作者 HUANG Xin 《Journal of Landscape Research》 2024年第2期25-29,共5页
Roads are crucial public spaces in cities and serve as a window to showcase the city’s characteristics.They serve not only as a means of urban transportation but also as a crucial spatial carrier for urban communicat... Roads are crucial public spaces in cities and serve as a window to showcase the city’s characteristics.They serve not only as a means of urban transportation but also as a crucial spatial carrier for urban communication activities and a significant location for meeting the increasing demands of people for a better quality of life.The current road infrastructure prioritizes the right of way for cars,neglecting the design of sidewalks and green belts within the road’s boundaries,and extension spaces between buildings and boundary lines of roads.There is a pressing need to improve street space in response to the demand for development transformation and the creation of a warmer city.This paper summarizes common problems in current road spaces,draws on the experience of excellent urban road spaces in foreign countries,discusses new ideas for the refined design of road spaces based on the transformation of road planning concepts,and suggests a reference standard for guiding detailed design.Simultaneously,the review of road construction will incorporate the detailed design of road space to enhance the role of planning in guiding and controlling the construction of road works. 展开更多
关键词 Road space refined design Communication space City perception
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Projection-Based Dimensional Reduction of Adaptively Refined Nonlinear Models
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作者 Clayton Little Charbel Farhat 《Communications on Applied Mathematics and Computation》 EI 2024年第3期1779-1800,共22页
Adaptive mesh refinement (AMR) is fairly practiced in the context of high-dimensional, mesh-based computational models. However, it is in its infancy in that of low-dimensional, generalized-coordinate-based computatio... Adaptive mesh refinement (AMR) is fairly practiced in the context of high-dimensional, mesh-based computational models. However, it is in its infancy in that of low-dimensional, generalized-coordinate-based computational models such as projection-based reduced-order models. This paper presents a complete framework for projection-based model order reduction (PMOR) of nonlinear problems in the presence of AMR that builds on elements from existing methods and augments them with critical new contributions. In particular, it proposes an analytical algorithm for computing a pseudo-meshless inner product between adapted solution snapshots for the purpose of clustering and PMOR. It exploits hyperreduction—specifically, the energy-conserving sampling and weighting hyperreduction method—to deliver for nonlinear and/or parametric problems the desired computational gains. Most importantly, the proposed framework for PMOR in the presence of AMR capitalizes on the concept of state-local reduced-order bases to make the most of the notion of a supermesh, while achieving computational tractability. Its features are illustrated with CFD applications grounded in AMR and its significance is demonstrated by the reported wall-clock speedup factors. 展开更多
关键词 Adaptive mesh refinement(AMR) Computational fluid dynamics Energy-conserving sampling and weighting(ECSW) Model order reduction Reduced-order model Supermesh
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Inhibition of Propionibacterium acnes by refined bamboo vinegar and preparation of the slow-release system with bamboo charcoal as the carrier
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作者 Ziyi Li Yanan Wang Sheng Zhang 《Journal of Dermatologic Science and Cosmetic Technology》 2024年第2期17-25,共9页
Background:Acne vulgaris is one of the most common skin diseases that can significantly impact a considerable proportion of individuals over their lifetime.Objective:This study focuses on the exploration of the applic... Background:Acne vulgaris is one of the most common skin diseases that can significantly impact a considerable proportion of individuals over their lifetime.Objective:This study focuses on the exploration of the application potential of bamboo vinegar in cosmetics.Materials and Methods:The stock solution of bamboo vinegar is subjected to reduced-pressure distillation at different temperatures to obtain refined bamboo vinegar.Then,inhibition of Propionibacterium acnes(P.acnes)by refined bamboo vinegar is observed.Moreover,the refined bamboo vinegar is adsorbed and released with activated bamboo charcoal as the carrier.In all,this study aims to probe into the mechanism of the controlledrelease system of bamboo vinegar.Results:The results shows that the harmful substances(tar)in bamboo vinegar distilled at 70℃decreased by 94.44%,which is a more notable decrease compared with that in the stock solution.The total organic acid content in bamboo vinegar after reduced-pressure distillation is 11.840%,reaching the national standard for refined bamboo vinegar(GB/T 31734–2015).Additionally,the minimum inhibitory concentration of refined bamboo vinegar against P.acnes using the punch method is 7.90 mg/mL.This indicates that refined bamboo vinegar has the potential as a prospective raw material for formulations in anti-acne cosmetic products.Furthermore,the release rate of bamboo charcoal/bamboo vinegar in water for 15 min reaches 70.57%,which then slows down to a plateau.The slow-release behavior is agreed with the Ritger-Peppas model and is beneficial to relieve the irritation of bamboo vinegar to the skin and lengthen its bacteriostatic duration.Conclusion:The foregoing conclusions can serve as the theoretical foundation for the application of bamboo vinegar in anti-acne cosmetics. 展开更多
关键词 Bamboo vinegar refinEMENT Propionibacterium acne Bamboo charcoal
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Exploring the Application of Refined Management in University Financial Management
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作者 Linlin Wang 《Proceedings of Business and Economic Studies》 2024年第5期164-168,共5页
The refined management of university finances primarily involves optimizing management methods and continuously improving financial management levels.This process helps enhance fund utilization efficiency,optimize res... The refined management of university finances primarily involves optimizing management methods and continuously improving financial management levels.This process helps enhance fund utilization efficiency,optimize resource allocation,ensure the rational use of educational funds,and provide solid financial support for the development of teaching,research,and other university undertakings.This paper explores the application of refined management in university financial management. 展开更多
关键词 refined management University financial management Educational reform
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Refined Aerodynamic Test of Wide-Bodied Aircraft and Its Application 被引量:1
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作者 Dawei Liu Zhiwei Jin +2 位作者 Xin Peng Gang Liu Yue Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第9期2691-2713,共23页
The large dual-channel wide-bodied aircraft has a long range and a high cruise Mach number.Therefore,its aerodynamic design requires a high level ofwind tunnel test refinement.Based on the requirements of aerodynamic ... The large dual-channel wide-bodied aircraft has a long range and a high cruise Mach number.Therefore,its aerodynamic design requires a high level ofwind tunnel test refinement.Based on the requirements of aerodynamic design for the future wide-bodied aircraft and the characteristics of high-speed wind tunnel tests,the error theory is introduced to analyze the factors affecting the accuracy of the test data.This study carries out a series of research on the improvement of refined aerodynamic test technology in an FL-26 wind tunnel,including design and optimization of the support system of wide-bodied aircraft,model attitude angle measurement,Mach number control accuracy,measurement and control system stability,test data correction and perfection,high-precision force balance and standard model development.In addition,the effect of the standard specification of the refined aerodynamic test is investigated to improve the data quality.The research findings have been applied in the standard model test and subsequent models of wide-bodied aircraft.The results show that whenMach numbers are less than 0.9,the control accuracy of Mach numbers in the FL-26 wind tunnel is smaller than 0.001 and the measurement error of attack angle is smaller than 0.01°.Therefore,it has the ability to correct the data influenced by factors,such as support/wall interference,model deformation,floating resistance and airflow deflection angle.The repeatability accuracy of the standard model’s comparison test shows that the lift coefficient is less than or equal to 0.0012,the drag coefficient is less than or equal to 0.00004,pitching moment coefficient is less than or equal to 0.0004.The bending resolution of the model’s deformation measurement is less than 0.2 mm,and the tensional deformation is smaller than 0.04°.The revised aerodynamic data and model deformation measurement results have good agreement with that of the ETW wind tunnel.The results demonstrate that the improved technology presented in this paper can significantly enhance the refined aerodynamic test of wide-bodied aircraft. 展开更多
关键词 Wide-bodied aircraft standard model wind tunnel test refinEMENT aerodynamic characteristics
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Refined mathematical model for the breaching of concrete-face sand-gravel dams due to overtopping failure
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作者 QIU Wen LI Yan-long +2 位作者 WEN Li-feng WANG Jing YIN Qiao-gang 《Journal of Mountain Science》 SCIE CSCD 2023年第3期670-687,共18页
Overtopping is one of the main reasons for the breaching of concrete-face sand-gravel dams(CFSGDs).In this study,a refined mathematical model was established based on the characteristics of the overtopping breaching o... Overtopping is one of the main reasons for the breaching of concrete-face sand-gravel dams(CFSGDs).In this study,a refined mathematical model was established based on the characteristics of the overtopping breaching of CFSGDs.The model characteristics were as follows:(1)Based on the Renormailzation Group(RNG)k-εturbulence theory and volume of fluid(VOF)method,the turbulent characteristics of the dam-break flow were simulated,and the erosion surface of the water and soil was tracked;(2)In consideration of the influence of the change in the sediment content on the dam-break flow,the dam material transport equation,which could reflect the characteristics of particle settlement and entrainment motion,was used to simulate the erosion process of the sand gravels;(3)Based on the bending moment balance method,a failure equation of the concrete face slab under dead weight and water load was established.The proposed model was verified through a case study on the failure of the Gouhou CFSGD.The results showed that the proposed model could well simulate the erosion mode of the special vortex flow of the CFSGD scouring the support body of the concrete face slab inward and reflect the mutual coupling relationship between the dam-break flow,sand gravels,and concrete face slabs.Compared with the measured values,the relative errors of the peak discharge,final breach average width,dam breaching duration,and maximum failure length of the face slab calculated using the proposed model were all less than 12%,thus verifying the rationality of the model.The proposed model was demonstrated to perform better and provide more detailed results than three selected parametric models and three simplified mathematical models.The study results can aid in establishing the risk level and devising early warning strategies for CFSGDs. 展开更多
关键词 Concrete-face sand-gravel dam OVERTOPPING Dam-break flow Concrete face slab failure refined mathematical model
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Refined disturbance observer based prescribed performance fixed-time control of high-speed EMS trains with track irregularities
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作者 Yiran Xie Boyang Zhao Xiuming Yao 《High-Speed Railway》 2023年第3期171-178,共8页
High-speed Electromagnetic Suspension(EMS)train is continuously impacted by the irregularity of the track,which worsens the levitation performance of the train.In this paper,a composite control scheme for the EMS is p... High-speed Electromagnetic Suspension(EMS)train is continuously impacted by the irregularity of the track,which worsens the levitation performance of the train.In this paper,a composite control scheme for the EMS is proposed to suppress track irregularities by integrating a Refined Disturbance Observer(RDO)and a Prescribed Performance Fixed-Time Controller(PPFTC).The RDO is designed to estimate precisely the track irregularities and lumped disturbances with uncertainties and exogenous disturbances in the suspension system,and reduce input chattering by applying to the disturbance compensation channel.PPFTC is designed to converge the suspension air gap error to equilibrium point with prescribed performance by completing error conversion,and solve the fast dynamic issue of EMS.And the boundary of overshoot and steady-state is limited in the ranged prescribed.A theoretical analysis is conducted on the stability of the proposed control method.Finally,the effectiveness and reasonability of the proposed composite anti-disturbance control scheme is verified by simulation results. 展开更多
关键词 High-speed electromagnetic suspension train Track irregularity refined disturbance observer Prescribed performance Fixed-time control
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Refinement Mechanism of Microstructure of Undercooled Nickel Based Alloys
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作者 杜文华 HOU Kai +6 位作者 XU Xuguang Ismal Saad Willey Liew Yun Hsien AN Hongen Nancy Julius Siambun Bih-Lii Chuab 王洪福 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第4期1041-1047,共7页
Through the use of purification and recirculation superheating techniques on molten glass,the Ni65Cu33Co2 alloy was successfully undercooled to a maximum temperature of 292 K.High-speed photography was employed to cap... Through the use of purification and recirculation superheating techniques on molten glass,the Ni65Cu33Co2 alloy was successfully undercooled to a maximum temperature of 292 K.High-speed photography was employed to capture the process of interface migration of the alloy liquid,allowing for an analysis of the relationship between the morphological characteristics of the alloy liquid solidification front and the degree of undercooling.Additionally,the microstructure of the alloy was examined using metallographic microscopy,leading to a systematic study of the microscopic morphological characteristics and evolution laws of the refined structure during rapid solidification.The research reveals that the grain refining mechanism of the Ni-Cu-Co ternary alloy is consistent with that of the binary alloy(Ni-Cu).Specifically,under low undercooling conditions,intense dendritic remelting was found to cause grain refinement,while under high undercooling conditions,recrystallization driven by accumulated stress and plastic strain resulting from the interaction between the liquid flow and the primary dendrites caused by rapid solidification was identified as the main factor contributing to grain refinement.Furthermore,the study highlights the significant role of the Co element in influencing the solidification rate and reheat effect of the alloy.The addition of Co was also found to facilitate the formation of non-segregated solidification structure,indicating its importance in the overall solidification process. 展开更多
关键词 grain refinement RECALESCENCE RECRYSTALLIZATION UNDERCOOLING
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Strength and plasticity improvement induced by strong grain refinement after Zr alloying in selective laser-melted AlSiMg1.4 alloy
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作者 Yao-xiang GENG Chun-feng ZAI +3 位作者 Jiang YU Hao TANG Hong-wei LÜ Zhi-jie ZHANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第9期2733-2742,共10页
In order to enhance the mechanical properties of the selective laser-melted(SLM) high-Mg content AlSiMg1.4 alloy,the Zr element was introduced.The influence of Zr alloying on the processability,microstructure,and mech... In order to enhance the mechanical properties of the selective laser-melted(SLM) high-Mg content AlSiMg1.4 alloy,the Zr element was introduced.The influence of Zr alloying on the processability,microstructure,and mechanical properties of the alloy was systematically investigated through performing microstructure analysis and tensile testing.It was demonstrated that the SLM-fabricated AlSiMg1.4-Zr alloy exhibited high process stability with a relative density of over 99.5% at various process parameters.Besides,the strong grain refinement induced by the primary Al3Zr particle during the melt solidification process simultaneously enhanced both the strength and plasticity of the alloy.The values for the yield strength,ultimate tensile strength,and elongation of the SLM-fabricated AlSiMg1.4-Zr were(343±3) MPa,(485±4) MPa,and(10.2±0.2)%,respectively,demonstrating good strengthplasticity synergy in comparison to the AlSiMg1.4 and other Al-Si-based alloys fabricated by SLM. 展开更多
关键词 selective laser melting process stability grain refinement microstructure mechanical properties
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Grain refinement of Mg-Ca alloys by native MgO particles
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作者 Shihao Wang Yun Wang +1 位作者 Quentin M.Ramasse Zhongyun Fan 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第3期980-996,共17页
In Mg-Ca alloys the grain refining mechanism,in particular regarding the role of nucleant substrates,remains the object of debates.Although native MgO is being recognised as a nucleating substrate accounting for grain... In Mg-Ca alloys the grain refining mechanism,in particular regarding the role of nucleant substrates,remains the object of debates.Although native MgO is being recognised as a nucleating substrate accounting for grain refinement of Mg alloys,the possible interactions of MgO with alloying elements that may alter the nucleation potency have not been elucidated yet.Herein,we design casting experiments of Mg-xCa alloys varied qualitatively in number density of native MgO,which are then comprehensively studied by advanced electron microscopy.The results show that grain refinement is enhanced as the particle number density of MgO increases.The native MgO particles are modified by interfacial layers due to the co-segregation of Ca and N solute atoms at the MgO/Mg interface.Using aberration-corrected scanning transmission electron microscopy and electron energy loss spectroscopy,we reveal the nature of these Ca/N interfacial layers at the atomic scale.Irrespective of the crystallographic termination of MgO,Ca and N co-segregate at the MgO/Mg interface and occupy Mg and O sites,respectively,forming an interfacial structure of a few atomic layers.The interfacial structure is slightly expanded,less ordered and defective compared to the MgO matrix due to compositional deviations,whereby the MgO substrate is altered as a poorer template to nucleate Mg solid.Upon solidification in a TP-1 mould,the impotent MgO particles account for the grain refining mechanism,where they are suggested to participate into nucleation and grain initiation processes in an explosive manner.This work not only reveals the atomic engineering of a substrate through interfacial segregation but also demonstrates the effectiveness of a strategy whereby native MgO particles can be harnessed for grain refinement in Mg-Ca alloys. 展开更多
关键词 Mg-Ca alloy Grain refinement MGO Interfacial segregation STEM/EELS Solidification.
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Differential distribution of authenticity results of different varieties of refined honey based on stable isotope ratio method
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作者 Si-Yuan Ma Yu-Feng Hu +7 位作者 Xiao-Tong Wei Meng-Lin Wang Shuang-Hui Shi Ming-Rui Jiang Hui-Nan Wang Jing-Qiu Zhang Ying-Zi Wang Dao-Bing Wang 《TMR Modern Herbal Medicine》 2023年第3期44-51,共8页
Objective Using the stable isotope ratio method for the authenticity identification and variety identification of refined honey.Methods In this paper,a total of 17 samples of different varieties of refined honey were ... Objective Using the stable isotope ratio method for the authenticity identification and variety identification of refined honey.Methods In this paper,a total of 17 samples of different varieties of refined honey were used to obtain refined honey proteins by precipitation with sodium tungstate solution and sulphuric acid solution.The isotope mass spectrometer was used to simultaneously detect theδ^(13)C values of refined honey proteins and refined honey as well as theδ^(18)O andδ^(2)H values of refined honey,processed of the results obtained,analysed the authenticity of the samples and conduct a variety identification study.Results Tested of the resulting honey samples,the results showed that four batches of refined honey did not up to standard,two batches of C-4 vegetable syrup were detected as adulterated,and two batches of protein were not detected.Theδ^(18)O andδ^(2)H values of refined honey were also found to be effective in distinguishing the varietal origin of refined honey to a certain extent.Conclusions The stable isotope ratio method is useful in the authenticity identification of refined honey,and provides new ideas to further promote the authenticity of refined honey and variety identification research. 展开更多
关键词 the stable isotope ratio refined honey AUTHENTICITY variety identification
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Effect of addition temperature on dispersion behavior and grain refinement efficiency of MgO introduced into Mg alloy
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作者 Le ZAI Xin TONG +1 位作者 Yun WANG Xiao-huai XUE 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第8期2491-2506,共16页
The effect of addition temperature of MgO particles(MgOp)on their dispersion behavior and the efficiency of grain refinement in AZ31 Mg alloy was investigated.In addition,the grain refinement mechanism was systematica... The effect of addition temperature of MgO particles(MgOp)on their dispersion behavior and the efficiency of grain refinement in AZ31 Mg alloy was investigated.In addition,the grain refinement mechanism was systematically studied by microstructure characterization,thermodynamic calculation,and analysis of solidification curves.The results show that the grain size of AZ31 Mg alloy initially decreases and then increases as the MgOp addition temperature is increased from 720 to 810℃,exhibiting a minimum value of 136μm at 780℃.The improved grain refinement efficiency with increasing MgOp addition temperature can be attributed to the reduced Mg melt viscosity and enhanced wettability between MgOp and Mg melt.Furthermore,a corresponding physical model describing the solidification behavior and grain refinement mechanism was proposed. 展开更多
关键词 grain refinement MgO nucleation particles AZ31 alloy addition temperature dispersion behavior
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Integrated multi-scale approach combining global homogenization and local refinement for multi-field analysis of high-temperature superconducting composite magnets
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作者 Hanxiao GUO Peifeng GAO Xingzhe WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第5期747-762,共16页
Second-generation high-temperature superconducting(HTS)conductors,specifically rare earth-barium-copper-oxide(REBCO)coated conductor(CC)tapes,are promising candidates for high-energy and high-field superconducting app... Second-generation high-temperature superconducting(HTS)conductors,specifically rare earth-barium-copper-oxide(REBCO)coated conductor(CC)tapes,are promising candidates for high-energy and high-field superconducting applications.With respect to epoxy-impregnated REBCO composite magnets that comprise multilayer components,the thermomechanical characteristics of each component differ considerably under extremely low temperatures and strong electromagnetic fields.Traditional numerical models include homogenized orthotropic models,which simplify overall field calculation but miss detailed multi-physics aspects,and full refinement(FR)ones that are thorough but computationally demanding.Herein,we propose an extended multi-scale approach for analyzing the multi-field characteristics of an epoxy-impregnated composite magnet assembled by HTS pancake coils.This approach combines a global homogenization(GH)scheme based on the homogenized electromagnetic T-A model,a method for solving Maxwell's equations for superconducting materials based on the current vector potential T and the magnetic field vector potential A,and a homogenized orthotropic thermoelastic model to assess the electromagnetic and thermoelastic properties at the macroscopic scale.We then identify“dangerous regions”at the macroscopic scale and obtain finer details using a local refinement(LR)scheme to capture the responses of each component material in the HTS composite tapes at the mesoscopic scale.The results of the present GH-LR multi-scale approach agree well with those of the FR scheme and the experimental data in the literature,indicating that the present approach is accurate and efficient.The proposed GH-LR multi-scale approach can serve as a valuable tool for evaluating the risk of failure in large-scale HTS composite magnets. 展开更多
关键词 epoxy-impregnated high-temperature superconducting(HTS)magnet multi-scale method global homogenization(GH) local refinement(LR) multi-field analysis
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Explainable machine learning model for predicting molten steel temperature in the LF refining process
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作者 Zicheng Xin Jiangshan Zhang +5 位作者 Kaixiang Peng Junguo Zhang Chunhui Zhang Jun Wu Bo Zhang Qing Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第12期2657-2669,共13页
Accurate prediction of molten steel temperature in the ladle furnace(LF)refining process has an important influence on the quality of molten steel and the control of steelmaking cost.Extensive research on establishing... Accurate prediction of molten steel temperature in the ladle furnace(LF)refining process has an important influence on the quality of molten steel and the control of steelmaking cost.Extensive research on establishing models to predict molten steel temperature has been conducted.However,most researchers focus solely on improving the accuracy of the model,neglecting its explainability.The present study aims to develop a high-precision and explainable model with improved reliability and transparency.The eXtreme gradient boosting(XGBoost)and light gradient boosting machine(LGBM)were utilized,along with bayesian optimization and grey wolf optimiz-ation(GWO),to establish the prediction model.Different performance evaluation metrics and graphical representations were applied to compare the optimal XGBoost and LGBM models obtained through varying hyperparameter optimization methods with the other models.The findings indicated that the GWO-LGBM model outperformed other methods in predicting molten steel temperature,with a high pre-diction accuracy of 89.35%within the error range of±5°C.The model’s learning/decision process was revealed,and the influence degree of different variables on the molten steel temperature was clarified using the tree structure visualization and SHapley Additive exPlana-tions(SHAP)analysis.Consequently,the explainability of the optimal GWO-LGBM model was enhanced,providing reliable support for prediction results. 展开更多
关键词 ladle furnace refining molten steel temperature eXtreme gradient boosting light gradient boosting machine grey wolf op-timization SHapley Additive exPlanation
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A REFINEMENT OF THE SCHWARZ-PICK ESTIMATES AND THE CARATHéODORY METRIC IN SEVERAL COMPLEX VARIABLES
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作者 Xiaosong LIU Taishun LIU 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1337-1346,共10页
In this article,we first establish an asymptotically sharp result on the higher order Fréchet derivatives for bounded holomorphic mappings f(x)=f(0)+∞∑s=1Dskf(0)(x^(sk))/(sk)!:B_(X)→B_(Y),where B_X is the unit... In this article,we first establish an asymptotically sharp result on the higher order Fréchet derivatives for bounded holomorphic mappings f(x)=f(0)+∞∑s=1Dskf(0)(x^(sk))/(sk)!:B_(X)→B_(Y),where B_X is the unit ball of X.We next give a sharp result on the first order Fréchet derivative for bounded holomorphic mappings F(X)=F(0+)∞∑s=KD^(s)f(0)(x^(8)/s!):B_(X)→B_(Y),where B_(X)is the unit ball of X.The results that we derive include some results in several complex variables,and extend the classical result in one complex variable to several complex variables. 展开更多
关键词 refined Schwarz-Pick estimate bounded holomorphic mapping Carathéodory metric first order Fréchet derivative higher order Fréchet derivatives
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