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Understanding the spatial interaction of ultrasounds based on three-dimensional dual-frequency ultrasonic field numerical simulation

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China Foundry 2024年第1期21卷 29-43页

作者： Zhao-yang Yin qi-chi Le Yan-chao Jiang Da-zhi Zhao qi-yu liao qi Zou Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

A transient 3D model was established to investigate the effect of spatial interaction of ultrasounds on the dual-frequency ultrasonic field in magnesium alloy *** effects of insertion depth and tip shape of the ultrasonic rods,input pressures and their ratio on the acoustic field distribution were discussed in ***,the spacing,angle,and insertion depth of two ultrasonic rods significantly affect the interaction between distinct *** a result,various acoustic pressure distributions and cavitation regions are *** spherical rods mitigate the longitudinal and transversal attenuation of acoustic pressure and expand the cavitation volume by 53.7%and 31.7%,respectively,compared to the plate and conical *** the input pressure will enlarge the cavitation region but has no effect on the acoustic pressure distribution *** acoustic pressure ratio significantly affects the pressure distribution and the cavitation region,and the best cavitation effect is obtained at the ratio of 2:1(P15:P20).

关键词： dual-frequency ultrasonic numerical model acoustic pressure spatial interaction magnesium alloy

Research progress on semi-continuous casting of magnesium alloys under external field

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China Foundry 2024年第5期21卷 516-524页

作者： qi-yu liao qi-chi Le Da-zhi Zhao Lei Bao Tong Wang Yong-hui Jia Key Laboratory of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China Key Laboratory of Lightweight Structural Materials Liaoning ProvinceNortheastern UniversityShenyang 110819China Key Laboratory of Light-weight Materials Nanjing Tech UniversityNanjing 210009China

High-performance magnesium alloys are moving towards a trend of being produced on a large scale and in an integrated *** foundational key to their successful production is the high-quality cast *** alloys produced through the conventional semi-continuous casting process inevitably contain casting defects,which makes it challenging to manufacture high-quality *** integration of external field assisted controlled solidification technology,which combines physical fields such as electromagnetic and ultrasonic fields with traditional semi-continuous casting processes,enables the production of high-quality magnesium alloy ingots characterized by a homogeneous microstructure and absence of *** article mainly summarizes the technical principles of those external field assisted casting *** focus is on elaborating the refinement mechanism of different types of electromagnetic fields,ultrasonic fields,and combined physical fields during the solidification of magnesium ***,the development prospects of producing highquality magnesium alloy ingots through semi-continuous casting under the external field were discussed.

关键词： semi-continuous casting electromagnetic field ultrasonic field magnesium alloys refinement mechanism

Ferrihydrite transformation impacted by coprecipitation of lignin:Inhibition or facilitation?

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Journal of Environmental Sciences 2024年第5期139卷 23-33页

作者： Lin Liu Zhihui Yang Weichun Yang Wen Jiang qi liao Mengying Si Feiping Zhao School of Metallurgy and Environment Central South UniversityChangsha 410083China Chinese National Engineering Research Center for Control&Treatment of Heavy Metal Pollution(CNERC-CTHMP) Changsha 410083China

Lignin is a common soil organic matter that is present in soils,but its effect on the transformation of ferrihydrite(Fh)remains *** matter is generally assumed to inhibit Fh ***,lignin can reduce Fh to Fe(Ⅱ),in which Fe(Ⅱ)-catalyzed Fh transformation ***,the effects of lignin on Fh transformation were investigated at 75℃ as a function of the lignin/Fh mass ratio(0-0.2),pH(4-8)and aging time(0-96 hr).The results of Fh-lignin samples(mass ratios=0.1)aged at different pH values showed that for Fh-lignin the time of Fh transformation into secondary crystalline minerals was significantly shortened at pH 6 when compared with pure Fh,and the Fe(Ⅱ)-accelerated transformation of Fh was strongly dependent on *** pH 6,at low lignin/Fh mass ratios(0.05-0.1),the time of secondary mineral formation decreased with increasing lignin *** high lignosulfonate-content material(lignin:Fh=0.2),Fh did not transform into secondary minerals,indicating that lignin content plays a major role in Fh *** addition,lignin affected the pathway of Fh transformation by inhibiting goethite formation and facilitating hematite *** effect of coprecipitation of lignin on Fh transformation should be useful in understanding the complex iron and carbon cycles in a soil environment.

关键词： Ferrihydrite transformation Lignin Hematite Goethite Fe(Ⅱ)-catalyzed Reactive Fe(Ⅲ)species

An integrated MINLP model for multi-party coordination in downstream oil supply chain

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Petroleum Science 2024年第3期21卷 2066-2079页

作者： Rui qiu Bo Zhang Wei Zhao Ren-Fu Tu Man-qiu He qi liao Yong-Tu Liang National Engineering Laboratory for Pipeline Safety/Beijing Key Laboratory of Urban Oil and Gas Distribution Technology China University of Petroleum-BeijingFuxue Road No.18Changping DistrictBeijing102249PR China Strategy&Implementation Department PipeChinaDongtucheng Road No.5Chaoyang DistrictBeijing100013PR China

Cooperation among enterprises can bring overall and individual performance improvement,and a smooth coordination method is ***,due to the lack of customized coordination methods,cooperation in the downstream oil supply chain cannot be carried out *** paper intends to propose a multi-party coordination method to promote cooperation between oil shippers and pipeline operator by optimizing oil transportation,oil substitution and pipeline pricing *** integrated game-theoretic modeling and analysis approach is developed to characterize the operation behaviors of all stakeholders in the downstream oil supply *** proposed mixed integer nonlinear programming model constrains supply and demand capacity,transportation routes,oil substitution rules and pipeline freight *** transformation and price discretization are introduced for model linear *** experiments are carried out in the oil distribution system in South *** results show that compared to the business-as-usual scheme,the new scheme saves transportation cost by 3.48%,increases pipeline turnover by 5.7%,and reduces energy consumption and emissions by 7.66%and 6.77%.It is proved that the proposed method improves the revenue of the whole system,achieves fair revenue distribution,and also improves the energy and environmental benefits of the oil supply chain.

关键词： Downstreamoil supplychain Multi-partycoordination Cooperative game Mixed integernonlinear programming model Pipeline transportation Revenue distribution

Effect of Artificial Cooling Extrusion on Microstructure and Mechanical Properties of Mg–Zn–Y Alloys

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1115-1127页

作者： qi-Yu liao Da-Zhi Zhao qi-Chi Le Wen-Xin Hu Yan-Chao Jiang Wei-Yang Zhou Liang Ren Dan-Dan Li Zhao-Yang Yin School of Materials Science and Engineering Northeastern UniversityShenyang110819China Key Laboratory of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang110819China Key Laboratory of Lightweight Structural Materials Liaoning ProvinceNortheastern UniversityShenyang110819China Baotou Research Institute of Rare Earths Baotou014000China

Microstructure and mechanical properties of Mg–Zn–Y alloys with different Zn/Y atomic ratios with or without artificial cooling (AC) extrusion were systematically investigated in this work. The results show that bimodal microstructure consisting of submicron dynamic recrystallized (DRXed) grains with high fraction of low-angle grain boundaries (LAGBs) and elongated unDRXed grains was formed in Mg_(98.7)Zn_(1)Y_(0.3) alloy with AC extrusion. The AC process effectively limits the growth of precipitated phases, and large amount of nanoscale precipitates were dynamically precipitated during the extrusion process. AC extrusion could effectually refine the lamellar 14H LPSO phases and inhibit the transition from stacking faults to LSPO phases in Mg_(98)Zn_(1)Y_(1) alloy and the narrow LPSO phase in Mg_(98)Zn_(1)Y_(1)-AC alloy which could promote the nucleation of DRXed grains. The AC extrusion significantly improves the strength of Mg–Zn–Y alloys. Owing to AC extrusion, the strength improvement of Mg_(98.7)Zn_(1)Y_(0.3) alloy is mainly attributed to fine grain strengthening, dislocation strengthening, and nano-phases precipitation strengthening. After AC process, more fine grains and nano-phases jointly strengthen the Mg_(98)Zn_(1)Y_(1) alloy. The Mg_(98)Zn_(1)Y_(1) alloy obtains optimal mechanical properties after extrusion at 623 K, with ultimate tensile strength (UTS) of 406 MPa, yield strength (YS) of 388 MPa, and elongation (EL) of 5.6%.

关键词： Mg-Zn-Y Artificial cooling Extrusion Microstructure Mechanical properties

Production of higher excited quarkonium pair at the super Z factory

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Chinese Physics C 2024年第7期48卷 45-54页

作者：廖其力蒋军 Chongqing College of Mobile Telecommunications Chongqing 401520China Chongqing Key Laboratory of Public Big Data Security Technology Chongqing 401520China School of Physics Shandong UniversityJinan 250100China

The heavy constituent quark pair of the heavy quarkonium is produced perturbatively and subsequently undergoes hadronization into the bound state *** production of the heavy quarkonium is essential to testing our understanding of quantum chromodynamics(QCD)in both perturbative and non-perturbative *** electron-positron collider will provide a suitable platform for the precise study of the heavy *** higher excited heavy quarkonium may contribute significantly to the ground states,which should be considered for sound *** study the production rates of the higher excited states quarkonium pair in■at the future Z factory under the non-relativistic QCD(NRQCD)framework,where the■represents the color-singlet states■The differential angle distribution of cross sections■is *** also discuss the uncertainties of cross sections caused by the varying quark masses and the renormalization scaleμ.We show that significant numbers of events for pairs of higher excited state quarkonia can be generated at the super Z factory.

关键词： Z boson decays pair of higher excited quarkonia NRQCD D0I:10.1088/1674-1137/ad3c2e

A review on the transformation of birnessite in the environment:Implication for the stabilization of heavy metals

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Journal of Environmental Sciences 2024年第5期139卷 496-515页

作者： Miao Shi qingzhu Li qingwei Wang Xuelei Yan Bensheng Li Linhai Feng Chao Wu Rongrong qiu Hongkai Zhang Zhihui Yang Weichun Yang qi liao Liyuan Chai School of Metallurgy and Environment Central South UniversityChangsha 410083China National Engineering Research Centre for Control and Treatment ofHeavy Metal Pollution Central South UniversityChangsha 410083China Water Pollution Control Technology Key Lab of Hunan Province Changsha 410083China

Birnessite is ubiquitous in the natural environment where heavy metals are retained and easily *** surface properties and structure of birnessite change with the changes in external environmental conditions,which also affects the fate of heavy *** the effect and mechanism of the birnessite phase transition process on heavy metals is the key to taking effective measures to prevent and control heavy metal ***,the four transformation pathways of birnessite are summarized first in this ***,the relationship between transformation pathways and environmental conditions is *** relevant environmental conditions include abiotic(e.g.,co-existing ions,pH,oxygen pressure,temperature,electric field,light,aging,pressure)and biotic factors(e.g.,microorganisms,biomolecules).The phase transformation is achieved by the key intermediate of Mn(Ⅲ)through interlayer-condensation,folding,neutralizationdisproportionation,and dissolution-recrystallization *** AOS(average oxidation state)of Mn and interlayer spacing are closely correlated with the phase transformation of *** but not least,the mechanisms of heavy metals immobilization in the transformation process of birnessite are summed *** involve isomorphous substitution,redox,complexation,hydration/dehydration,*** transformation of birnessite and its implication on heavy metals will be helpful for understanding and predicting the behavior of heavy metals and the crucial phase of manganese oxides/hydroxides in natural and engineered environments.

关键词： Birnessite Transformation Heavy metals Pathways Mechanism

基于ArcGIS Engine的风暴潮淹没适应气候变化策略辅助决策系统开发

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中国海洋大学学报（自然科学版） 2024年第2期54卷 142-153页

作者：廖琪江文胜中国海洋大学环境科学与工程学院海洋环境与生态教育部重点实验室山东青岛266100

本研究构建了基于ArcGIS Engine的风暴潮淹没适应气候变化策略辅助决策系统,将风暴潮淹没适应气候变化策略研究过程流程化和简单化,并提供7个面向用户开放的决策端口,辅助决策者做出科学的风暴潮淹没适应气候变化策略选择。以青岛市风... 详细信息

本研究构建了基于ArcGIS Engine的风暴潮淹没适应气候变化策略辅助决策系统,将风暴潮淹没适应气候变化策略研究过程流程化和简单化,并提供7个面向用户开放的决策端口,辅助决策者做出科学的风暴潮淹没适应气候变化策略选择。以青岛市风暴潮淹没为例的系统应用,进一步验证了该系统能够切实提高研究过程的分析效率,为中国沿海地区的适应风暴潮灾害提供技术支持。

关键词：适应气候变化辅助决策系统 ArcGIS Engine 风暴潮淹没

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人工智能在眼底病全程管理中的革新与挑战

中华眼科杂志 2024年第7期60卷 559-565页

作者：张明廖祺杨婷婷四川大学华西医院眼科成都610041

人工智能(AI)在眼底病全程管理中展现出革新价值与广泛应用潜力,但也面临临床转化、数据质量、算法解释性、跨文化适应性等挑战。AI在糖尿病视网膜病变、年龄相关性黄斑变性等眼底病中,实现高效筛查、精确诊断、个性化治疗建议及预后预... 详细信息

人工智能(AI)在眼底病全程管理中展现出革新价值与广泛应用潜力,但也面临临床转化、数据质量、算法解释性、跨文化适应性等挑战。AI在糖尿病视网膜病变、年龄相关性黄斑变性等眼底病中,实现高效筛查、精确诊断、个性化治疗建议及预后预测。然而,AI对大规模、高质量、多样化的数据集需求与现有研究数据局限性之间的矛盾,以及黑箱模型的可解释性问题、医生与患者接受度、算法普适性等挑战,阻碍了其在眼科临床的广泛普及。为应对这些挑战,研究者们正探索采用联邦学习、标准化数据收集、前瞻性试验等方法,提升AI系统的稳健性、可解释性和实用性。尽管存在挑战,AI在眼底病管理中的优势显著,包括提升筛查效率、辅助个性化治疗、揭示疾病新特征及制定精准治疗策略,并通过5G、物联网等技术推动远程医疗发展。未来研究应继续解决现存问题,充分发挥AI在眼底病防治中的潜力,推动眼科服务迈向智能化、精准化、远程化,以满足全球眼健康需求。

关键词：人工智能眼底眼疾病疾病管理远程医学