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Omnidirectional simulation analysis of thermomechanical coupling mechanism in inertia friction welding of Ni-based superalloy

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Chinese Journal of Aeronautics 2025年第1期38卷 202-216页

作者： Chang-an LI Guoliang QIN hao WANG School of Materials Science and Engineering Shandong UniversityJinan 250061China

The coupling between heat and pressure is the kernel of inertia friction welding(IFW)and is still not fully understood.A novel 3D fully coupled finite element model based on a plastic friction pair was developed to simulate the IFW process of a Ni-based superalloy and reveal the omnidirectional thermo-mechanical coupling mechanism of the friction *** numerical model successfully simulated the deceleration,deformation processes,and peak torsional moments in IFW and captured the evolution of temperature,contact pressure,and *** simulated results were validated through measured thermal history,optical macrography,and axial *** results indicated that interfacial friction heat was the primary heat source,and plastic deformation energy only accounted for 4%of the *** increase in initial rotational speed and friction pressure elevated the peak temperature,reaching a maximum of 1525.5K at an initial rotational speed of 2000 r/min and friction pressure of 400 *** interface heat generation could form an axial temperature gradient exceeding 320K/*** radial inhomogeneities of heat generation and temperature were manifested in a concentric ring distribution with maximum heat flux and temperature ranging from 2/5 to 2/3 *** radial inhomogeneities were caused by increasing linear velocity along the radius and an opposite distribution of contact pressure,which could reach 1.7 times the set pressure at the *** circumferential inhomogeneity of thermomechanical distribution during rotary friction welding was revealed for the first time,benefiting from the 3D *** deflection and transformation of distribution in contact pressure and Mises stress were indicators of plastic deformation and transition of quasi-steady state *** critical Mises stress was 0.5 times the friction pressure in this *** presented modeling provides a reliable insight into the thermo-mechanical coupling mechanism of IFW and lays a solid found

关键词： Inertia friction welding Thermo-mechanical coupling Inhomogeneity Numerical simulation Ni-based superalloy

Three-dimensional line-of-sight-angle-constrained leader-following cooperative interception guidance law with prespecified impact time

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Chinese Journal of Aeronautics 2025年第1期38卷 491-506页

作者： hao YOU Xinlong CHANG Jiufen Zhao Rocket Force University of Engineering Xi’an 710025China

To address the problem of multi-missile cooperative interception against maneuvering targets at a prespecified impact time and desired Line-of-Sight(LOS)angles in ThreeDimensional(3D)space,this paper proposes a 3D leader-following cooperative interception guidance ***,in the LOS direction of the leader,an impact time-controlled guidance law is derived based on the fixed-time stability theory,which enables the leader to complete the interception task at a prespecified impact ***,in the LOS direction of the followers,by introducing a time consensus tracking error function,a fixed-time consensus tracking guidance law is investigated to guarantee the consensus tracking convergence of the ***,in the direction normal to the LOS,by combining the designed global integral sliding mode surface and the second-order Sliding Mode Control(SMC)theory,an innovative 3D LOS-angle-constrained interception guidance law is developed,which eliminates the reaching phase in the traditional sliding mode guidance laws and effectively saves energy ***,it effectively suppresses the chattering phenomenon while avoiding the singularity issue,and compensates for unknown interference caused by target maneuvering online,making it convenient for practical engineering ***,theoretical proof analysis and multiple sets of numerical simulation results verify the effectiveness,superiority,and robustness of the investigated guidance law.

关键词： Three-dimensional cooperative interception Leader-following missiles Prespecified impact time LOS-angle-constrained Fixed-time stability Global integral sliding mode

2024 Annual Report of China Mineral Resources (copper, gold, coal, etc.)

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China Geology 2025年第1期8卷 235-236页

作者： Li-qiong Jia Xi-jie chen Zi-guo hao Development and Research Center China Geological SurveyMinistry of Natural ResourcesBeijing 100037China

In October 2024,the Ministry of Natural Resources of PRC released the 2024 China Mineral Resources Report,which focuses on new progress since 2023 in the geological and mineral survey and evaluation,mineral resource exploration and development,mine ecological restoration,green mine construction,new changes in mineral resource policies and regulations,new measures in mineral resource management,new situations in scientific and technological innovation,as well as the new achievements of the international geological and mineral cooperation.

关键词： gold copper resource

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概率计算及混合概率计算

电子学报 2024年第2期52卷 428-440页

作者：李洪革陈宇昊吴俊毅宋印杰朱新宇北京航空航天大学电子信息工程学院北京市100191

非位置概率数的计算机制已经成为边缘计算片上系统的新范式.本文介绍了概率计算(stochastic computing)的起源、发展和目前国内外的研究现状.针对传统概率计算存在诸如计算时延长、脉冲串信息携带效率低等问题,本文提出了二进制数-概率... 详细信息

非位置概率数的计算机制已经成为边缘计算片上系统的新范式.本文介绍了概率计算(stochastic computing)的起源、发展和目前国内外的研究现状.针对传统概率计算存在诸如计算时延长、脉冲串信息携带效率低等问题,本文提出了二进制数-概率脉冲串混合编码的混合概率数概念,并从数的表示机理上阐释了二进制数、概率数和混合概率数的数理关系,进而揭示了混合概率计算所具备的低时延、高算力和高能效比的计算特点.本文基于40 nm CMOS工艺设计混合概率深度神经网络,该神经网络芯片在内核面积仅0.73 mm×0.73 mm的条件下,设计4544个乘累加(MAC)单元.在时钟频率400 MHz条件下,总功率为102.3 mW,其中动态功耗仅97μW.通过ASIC芯片的实验测试表明,混合概率计算作为一种全新的颠覆性计算范式,与其他确定性、可扩展和全并行等概率计算方案相比,其能效比分别提高了50倍、2.5倍和3.26倍.

关键词：概率数概率计算混合概率数混合概率计算深度神经网络能效算力

Emission characteristics of biogenic volatile organic compounds in a subtropical pristine forest of southern China

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Journal of Environmental Sciences 2025年第2期148卷 665-682页

作者： Xi chen Daocheng Gong Youjing Lin Qiao Xu yujin Wang Shiwei Liu Qinqin Li Fangyuan Ma Jiangyong Li Shuo Deng hao Wang Boguang Wang Institute for Environmental and Climate Research Jinan UniversityGuangzhou 511443China Guangdong Provincial Observation and Research Station for Atmospheric Environment and Carbon Neutrality in Nanling Forests China Australia-China Centre for Air Quality Science and Management(Guangdong) Guangzhou 511443China Hainan Provincial Ecological and Environmental Monitoring Center Haikou 571126China

Emission characteristics of biogenic volatile organic compounds(BVOCs)from dominant tree species in the subtropical pristine forests of China are extremely *** we conducted in situ field measurements of BVOCs emissions from representative mature evergreen trees by using dynamic branch enclosures at four altitude gradients(600-1690ma.s.l.)in the Nanling Mountains of southern *** characteristics as well as seasonal and altitudinal variations were *** emission rates and canopyscale emission factors were then *** showed that BVOCs emission intensities in the wet season were generally higher than those in the dry *** were the dominant BVOCs emitted from most broad-leaved trees,accounting for over 70%of the *** superba,yushania basihirsuta and Altingia chinensis had relatively high emission intensities and secondary pollutant formation *** localized emission factors of isoprene were comparable to the defaults in the Model of Emissions of Gases and Aerosols fromNature(MEGAN),while emission factors of monoterpenes and sesquiterpenes were 2 to 58 times of those in the *** results can be used to update the current BVOCs emission inventory in MEGAN,thereby reducing the uncertainties of BVOCs emission estimations in forested regions of southern China.

关键词： Biogenic volatile organic compounds(BVOCs) Dynamic enclosure system Nanling Mountains Emission factors Emission rates Chemical reactivity

Hypercoagulation after neoadjuvant immunochemotherapy as a new prognostic indicator in patients with locally advanced gastric cancer undergoing surgery

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World Journal of Gastrointestinal Oncology 2025年第3期17卷 91-103页

作者： Tian-hao Li Xiong Sun cheng-Guo Li yu-Ping Yin Kai-Xiong Tao Department of Gastrointestinal Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022Hubei ProvinceChina

BACKGROUND Coagulation status is closely related to the progression of malignant *** the era of neoadjuvant immunochemotherapy(NICT),the prognostic utility of coagulation indicators in patients with locally advanced gastric cancer(LAGC)undergoing new treatments remains to be *** To determine whether hypercoagulation is an effective prognostic indicator in patients with LAGC who underwent radical resection after *** A retrospective analysis of clinical data from 104 patients with LAGC,who underwent radical resection after NICT between 2020 and 2023,was *** and fibrinogen concentrations were measured one week before NICT,and again one week before surgery,to analyze the association between these two indicators and their combined indices[non-hypercoagulation(D-dimer and fibrinogen concentrations within the upper limit of normal)vs hypercoagulation(D-dimer or fibrinogen concentrations above the upper limit of normal)]with *** radical resection,patients were followed-up *** median follow-up duration was 21 *** Data collected after NICT revealed that the three-year overall survival(OS)and disease-free survival(DFS)rates the non-hypercoagulation group were significantly better than those in the hypercoagulation group[94.4%vs 78.0%(P=0.019)and 87.0%vs 68.0%(P=0.027),respectively].Multivariate analysis indicated that hypercoagulation after NICT was an independent factor for poor postoperative OS[hazard ratio(HR)4.436,P=0.023]and DFS(HR 2.551,P=0.039).Pre-NICT data demonstrated no statistically significant difference in three-year OS between the non-hypercoagulation and hypercoagulation groups(88.3%vs 84.1%,respectively;P=0.443).CONCLUSION Hypercoagulation after NICT is an effective prognostic indicator in patients with LAGC undergoing radical gastrectomy.

关键词： Locally advanced gastric cancer Coagulation Neoadjuvant immunochemotherapy Prognosis Radical gastrectomy

Comprehensive Chlorine Suppression:Advances in Materials and System Technologies for Direct Seawater Electrolysis

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Nano-Micro Letters 2025年第5期17卷 297-325页

作者： Cenkai Zhao Zheyuan Ding Kunye Zhang Ziting Du Haiqiu Fang Ling chen hao Jiang Min Wang Mingbo Wu State Key Laboratory of Heavy Oil Processing College of New EnergyChina University of Petroleum(East China)Qingdao 266580People’s Republic of China Beijing National Laboratory for Molecular Sciences New Cornerstone Science LaboratoryCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871People’s Republic of China Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237People’s Republic of China

Seawater electrolysis offers a promising pathway to generate green hydrogen,which is crucial for the net-zero emission *** seawater electrolysis is severely limited by high energy demands and system complexity,while the direct seawater electrolysis bypasses pre-treatment,offering a simpler and more cost-effective ***,the chlorine evolution reaction and impurities in the seawater lead to severe corrosion and hinder electrolysis’s ***,we review recent advances in the rational design of chlorine-suppressive catalysts and integrated electrolysis systems architectures for chloride-induced corrosion,with simultaneous enhancement of Faradaic efficiency and reduction of electrolysis’s ***,promising directions are proposed for durable and efficient seawater electrolysis *** review provides perspectives for seawater electrolysis toward sustainable energy conversion and environmental protection.

关键词： Direct seawater electrolysis Oxygen evolution reaction Hydrogen evolution reaction Chlorine suppression Seawater electrolysis system

Polysaccharide from large leaf yellow tea activates the LXRα-ABCA1/ABCG1 pathway to ameliorate type 2 diabetes by regulating gut microbiota

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Food Science and Human Wellness 2025年

作者： hao chen Zhuang Wang Xinxin Pei Jielin chen Kaili Xuan Lei Gong Xinyu Zhou yuzhe Huang Yan chen School of Life Sciences， Anhui University Key Laboratory of Ecological Engineering and Biotechnology of Anhui Province Institutes of Physical Science and Information Technology， Anhui University Fugong yuanlveda Puluo Tea Industry Co.， Ltd.

Type 2 diabetes mellitus （T2DM） is a multifaceted metabolic condition characterized by chronic hyperglycemia （elevated blood sugar levels） and insulin resistance （IR）. We have isolated a new homogeneous polysaccharide， LYTP-3， (7.22 × 105Da) with anti-diabetic activity， from large leaf yellow tea （LYT） by biological activity-guided sequential separation and activity evaluation. Using a T2DM mouse model， we demonstrate that oral administration of LYTP-3 can reduce blood lipid levels， alleviate hyperglycemia and glucose tolerance， and inhibit insulin resistance. LYTP-3 ameliorated T2DM treatment by activating the liver X receptor alpha （LXRα）-ATP-binding cassette （ABC） transporter （LXRα-ABCA1/ABCG1） signaling pathway， which is regulated by the gut microbiota. The strain Lachnospiraceae bacterium A4 is potentially the key to this improvement. Additionally， we have solved the molecular structure of LYTP-3 using nuclear magnetic resonance （NMR）， and methylation analyses. The main backbone of LYTP-3 consists of 1，2，4-α-L-Rhap， 1，4-α-D-Galp， 1，6-α-D-Glcp， with branches of 1，4-β-D-Galp， 1，6-β-D-GalpA， 1，3，6-β-D-Manp， 1，2-α-L-Rhap， T-β-Manp， and T-β-Galp. The findings of this study suggest that LYTP-3 may serve as a potential gut microbiota modulator in the treatment of T2DM.

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Unusual roles of ceria as the support of a single-atom catalyst in hydroisomerization of n-heptane:Phase boundary acts as transport channels between different active centers

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Journal of Rare Earths 2025年第2期43卷 276-283页

作者： hao Qin Hui Wan Guofeng Guan State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringJiangsu National Synergetic Innovation Center for Advanced MaterialsNanjing Tech University

Hydroisomerization of n-alkanes plays an important role in fuel and lubricants *** catalysts with ultralow platinum loading have recently been reported successively for ***,the catalysts were prepared successfully with different methods to improve the catalytic *** conversion of 0.01%Pt1@CeOx/SAPO-11 prepared by co-calcination method（0.01%Pt1@CS-c） is 71.4%,25% higher than the other prepared by precipitation *** turnover frequency per active surface platinum site（TOFPt） of 0.01%Ptl@CS-c is as high as 13115 *** by the X-ray photoelectron spectroscopy（XPS） results,the quality of phase boundary/intersurface between ceria and zeolite is found significantly *** conjunction quality of phase boundary directly affects the spillover rate of intermediate species,which further leads to an apparent activity *** addition,the possible role of ceria in the reaction is discussed,rather than just as a carrier for the active metal atoms.

关键词： Rare earths Hydroisomerization Spillover Proximity Single-atom catalysis Intermediate