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Performance Study of Copper-Bearing High Strength Ship-Hull Steel

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Journal of Iron and Steel Research International 2011年第S1期18卷 422-426页

作者： LUO xiao-bing,yang Cai-fu,SU Hang,CHAI Feng (Central Iron and Steel Research Institute,Institute for Structural Materials,Beijing 100081,China) Cent Iron & Steel Res Inst Inst Struct Mat Beijing 100081 Peoples R China

The variation in microstructures and the mechanical properties of a Copper-bearing high strength ship-hull steel at different aging temperature was *** peak strength was obtained at the aging temperature of 450 ℃,which was attribute to the plentiful Cu precipitates and a bit of Nb(C,N).In the over-aged condition,both the partial recovery of matrix and the coarsening of Cu particles (10-60 nm) caused the loss of the yield strength (YS) and the improvement of *** increase of the ultimate tensile strength (UTS) at aging temperature above 660℃ due to the formation of alloy-rich island structure transformed from the austenite phase upon cooling,and complied with the mixture *** copper-bearing ship steel can exhibit an excellent combination of high strength and toughness while aging at 660 ℃ for 2 hours (UTS-818 MPa,YS-745 MPa,Akv-161 J at-40℃).

关键词： copper-bearing aging HSLA ship-hull steel

Expectant management of heterotopic cesarean scar pregnancy

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Chinese Medical Journal 2012年第7期125卷 1341-1344页

作者： BAI xiao-xia GAO Hui-juan yang xiao-fu DONG Ming-yue ZHU Yi-min Department of Reproductive Endocrinology Women’s HospitalSchool of MedicineZhejiang UniversityHangzhouZhejiang 310006China

Background Heterotopic cesarean scar pregnancy （HCSP） is a very rare but life-threatening entity and there is no optimal management strategy. Here we report a successfully managed case of HCSP with expectant treatment in a tertiary referral hospital. Methods A woman with HCSP after in vitro fertilization-embryo transfer opted for expectant treatment after five days of mild bleeding and ultrasound demonstrated cardiac activity disappearance of the scar pregnancy at 8＋4 weeks of gestation. Results The patient had mild to moderate bleeding during close monitoring. Three days later, speculum examination revealed the gestational mass was partly protruding at the os of the cervix and it was removed with forceps without massive hemorrhage. A healthy male baby was delivered by cesarean section at gestational age of 36＋4 weeks. Conclusions The expectant method might be an alternative option for a HCSP with loss of cardiac activity of the scar pregnancy, when applied under supportive management and with available emergency surgery facilities.

关键词： cesarean scar heterotopic pregnancy expectant treatment in vitro fertilization-embryo transfer

De novo synthesis of atropisomeric benzofurans via Cu/SPDO complex catalyzed asymmetric formal[3+2]annulation

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Science China Chemistry 2025年第1期68卷 174-180页

作者： Fan-xiao Meng Xing-Yu Wang Ka Lu Ju-Song yang fu-Min Zhang Ai-Jun Ma Bao Du Yong-Qiang Tu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Biotechnology and Health Sciences Wuyi UniversityJiangmen 529020China

Herein,the de novo synthesis of atropisomeric benzofurans through the Cu/spirocyclic-pyrrolidine-oxazoline(SPDO)complex catalyze asymmetric formal[3+2]cycloaddition between quinones and ynamides is explored,producing a range of structurally diverse axially chiral benzofurans in satisfactory yields with good to excellent ***,density functional theory calculations were applied to explain the possible reaction mechanism.

关键词： benzofuran atropisomers novel de novo synthetic strategy asymmetric formal[3+2]cycladdition Cu/SPDO complex DFT calculations

Metal-organic polyhedra as dynamic cross-linker for recyclable mixed matrix membranes with promising dimension stability

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Science China Chemistry 2025年第2期68卷 705-713页

作者： Linjie Lan Mingxin Zhang Haiyan xiao Wei Liu-fu Yuyan Lai Jiadong Chen Jia-fu Yin Panchao Yin State Key Laboratory of Luminescent Materials and Devices&South China Advanced Institute for Soft Matter Science and Technology Guangdong Basic Research Center of Excellence for Energy and Information Polymer MaterialsSouth China University of TechnologyGuangzhou 510641China State Key Laboratory of Marine Resource Utilization in South China Sea Hainan Provincial Key Lab of Fine ChemistrySchool of Chemical Engineering and TechnologyHainan UniversityHaikou 570228China

Mixed matrix membranes(MMMs)are designed by incorporating microporous inorganic fillers into polymer matrix for the integration of inorganics’excellent gas separation performance with polymers’promising ***,due to the complex interphase interaction,the prevention of long-term aging is still challenging and the poor processability/recyclability of MMMs hinders their extensive ***,a coordination assembly protocol is developed for the fabrication of MMMs with both excellent processability/recyclability upon thermal annealing and promising dimension stability even under high gas *** bearing isophthalic acid(IPA)as side chains are applied to coordinate with Cu^(2+)and the assembled 2.5 nm microporous metal-organic polyhedra(MOP),{Cu_(24)IPA_(24)},serves as multi-functional cross-linkers for the polymer network *** MOPs’well-defined microporosity grants MMMs the capability for O_(2)/N_(2) separation while their activated dynamics at high temperatures(>120℃)endows polymer networks with excellent *** contrast to conventional supramolecular units,the MOPs possess unique logarithmic ligand-exchange kinetics and they show nearly frozen bonding dynamics at room temperature,ensuring promising dimensional stability to overcome the long-term aging and high gas pressure *** work not only provides fundamental understanding of the unique relaxation dynamics of complex systems with intertwined dynamics of supramolecular bonds and polymer chains,but also paves new avenues for the fabrication of robust and recyclable MMMs and elastomers.

关键词： dynamic bonding metal-organic polyhedra mixed matrix membrane polymer recycling gas separation

Biomaterial‑based mechanical regulation facilitates scarless wound healing with functional skin appendage regeneration

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Military Medical Research 2025年第1期12卷 96-120页

作者： Ying-Ying Li Shuai-Fei Ji xiao-Bing fu Yu-Feng Jiang xiao-Yan Sun Research Center for Tissue Repair and Regeneration Affiliated to the Medical Innovation Research Department Chinese PLA General Hospital and PLA Medical CollegePLA Key Laboratory of Tissue Repair and Regenerative Medicine and Beijing Key Research Laboratory of Skin InjuryRepair and RegenerationResearch Unit of Trauma CareTissue Repair and RegenerationChinese Academy of Medical Sciences2019RU051Beijing 100048China Research Unit of Trauma Care Tissue Repair and RegenerationChinese Academy of Medical Sciences2019RU051Beijing 100048China 2Department of Tissue Regeneration and Wound RepairChinese PLA General HospitalBeijing 100853China

Scar formation resulting from burns or severe trauma can significantly compromise the structural integrity of skin and lead to permanent loss of skin appendages,ultimately impairing its normal physiological *** evidence underscores the potential of targeted modulation of mechanical cues to enhance skin regeneration,promoting scarless repair by influencing the extracellular microenvironment and driving the phenotypic *** field of skin repair and skin appendage regeneration has witnessed remarkable advancements in the utilization of biomaterials with distinct physical ***,a comprehensive understanding of the underlying mechanisms remains somewhat elusive,limiting the broader application of these *** this review,we present two promising biomaterial-based mechanical approaches aimed at bolstering the regenerative capacity of compromised *** first approach involves leveraging biomaterials with specific biophysical properties to create an optimal scarless environment that supports cellular activities essential for *** second approach centers on harnessing mechanical forces exerted by biomaterials to enhance cellular plasticity,facilitating efficient cellular reprogramming and,consequently,promoting the regeneration of skin *** summary,the manipulation of mechanical cues using biomaterial-based strategies holds significant promise as a supplementary approach for achieving scarless wound healing,coupled with the restoration of multiple skin appendage functions.

关键词： Scarless Wound healing Biomaterials Mechanical cues Skin appendages

Riemann-Hilbert Problem and Multiple High-order Poles Solutions of the Focusing mKdV Equation with Nonzero Boundary Conditions

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Acta Mathematicae Applicatae Sinica 2025年第1期41卷 234-251页

作者： Zi-yi WANG Shou-fu TIAN Jin-jie yang School of Mathematics China University of Mining and TechnologyXuzhou 221116China

The focusing modified Korteweg-de Vries(mKdV)equation with multiple high-order poles under the nonzero boundary conditions is first investigated via developing a Riemann-Hilbert(RH)*** begin with the asymptotic property,symmetry and analyticity of the Jost solutions,and successfully construct the RH problem of the focusing mKdV *** solve the RH problem when 1/S_(11)(k)has a single highorder pole and multiple high-order ***,we derive the soliton solutions of the focusing mKdV equation which corresponding with a single high-order pole and multiple high-order poles,***,the dynamics of one-and two-soliton solutions are graphically discussed.

关键词： Riemann-Hilbert approach focusing mKdV equation nonzero boundary conditions multiple high-order poles soliton solutions

Seismic design of variable cross-section damped steel support frame for post equipment

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Earthquake Engineering and Engineering Vibration 2025年第1期24卷 155-167页

作者： yang Zhenyu Ma Yuhong Zhao Guifeng Feng Zhiwei fu Mingyang Earthquake Engineering Research&Test Center Guangzhou UniversityGuangzhou 510405China School of Civil Engineering Guangzhou UniversityGuangzhou 510620China Guangdong Provincial Key Laboratory of Earthquake Engineering and Applied Technology Guangzhou 510405China

High-voltage electrical post equipment is generally installed on steel supports,which amplifies the seismic inputs and degrades the seismic performance of *** study proposed a variable cross-section damped steel support frame(VCDFS)with viscous dampers to reduce seismic responses of both tall and low-rise electrical *** VCDFS contains a trapezoidal damper layer to generate rocking motions,enabling the diagonal viscous dampers to dissipate seismic inputs.A theoretical model of post equipment with VCDFS is established,and an optimal design procedure is *** analysis shows that the remaining static stiffness ratio λ_(k) is the key parameter that determines the effectiveness of the *** VCDFS reduces the average displacement and stress response of a post insulator by 39.4%and 44.6%,respectively,together with a significant decrease in the dynamic amplification ***,it is recommended to use the VCDFS instead of the conventional latticed-steel frame in earthquake zones.

关键词： electrical post equipment steel support frame passive control seismic performance upgrading

Joint Retrieval of PM_(2.5) Concentration and Aerosol Optical Depth over China Using Multi-Task Learning on FY-4A AGRI

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Advances in Atmospheric Sciences 2025年第1期42卷 94-110页

作者： Bo LI Disong fu Ling yang Xuehua FAN Dazhi yang Hongrong SHI Xiang’ao XIA Electronic Engineering College Chengdu University of Information TechnologyChengdu 610225China Tianjin Meteorological Radar Research Trial Center Tianjin Meteorological BureauTianjin 300074China Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Research Centre on Meteorological Observation Engineering Technology China Meteorological AdministrationBeijing 100081China Key Laboratory of Atmospheric Environment and Extreme Meteorology Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China School of Electrical Engineering and Automation Harbin Institute of TechnologyHarbin 150001China University of Chinese Academy of Sciences Beijing 100049China

Aerosol optical depth(AOD)and fine particulate matter with a diameter of less than or equal to 2.5μm(PM_(2.5))play crucial roles in air quality,human health,and climate ***,the complex correlation of AOD–PM_(2.5)and the limitations of existing algorithms pose a significant challenge in realizing the accurate joint retrieval of these two parameters at the same *** this point,a multi-task learning(MTL)model,which enables the joint retrieval of PM_(2.5)concentration and AOD,is proposed and applied on the top-of-the-atmosphere reflectance data gathered by the Fengyun-4A Advanced Geosynchronous Radiation Imager(FY-4A AGRI),and compared to that of two single-task learning models—namely,Random Forest(RF)and Deep Neural Network(DNN).Specifically,MTL achieves a coefficient of determination(R^(2))of 0.88 and a root-mean-square error(RMSE)of 0.10 in AOD *** comparison to RF,the R^(2)increases by 0.04,the RMSE decreases by 0.02,and the percentage of retrieval results falling within the expected error range(Within-EE)rises by 5.55%.The R^(2)and RMSE of PM_(2.5)retrieval by MTL are 0.84 and 13.76μg m~(-3)*** with RF,the R^(2)increases by 0.06,the RMSE decreases by 4.55μg m~(-3),and the Within-EE increases by 7.28%.Additionally,compared to DNN,MTL shows an increase of 0.01 in R^(2)and a decrease of 0.02 in RMSE in AOD retrieval,with a corresponding increase of 2.89%in *** PM_(2.5)retrieval,MTL exhibits an increase of 0.05 in R^(2),a decrease of 1.76μg m~(-3)in RMSE,and an increase of 6.83%in *** evaluation suggests that MTL is able to provide simultaneously improved AOD and PM_(2.5)retrievals,demonstrating a significant advantage in efficiently capturing the spatial distribution of PM_(2.5)concentration and AOD.

关键词： AOD PM_(2.5) FY-4A multi-task learning joint retrieval

Unsupervised multiplex graph diffusion networks with multi-level canonical correlation analysis for multiplex graph representation learning

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Science China(Information Sciences) 2025年第03期68卷 66-79页

作者： Sichao fu Qinmu PENG yange HE Baokun DU Bin ZOU xiao-Yuan JING Xinge YOU School of Electronic Information and Communications Huazhong University of Science and Technology Platform Operation and Marketing Center JD Retail Faculty of Mathematics and Statistics Hubei Key Laboratory of Applied Mathematics Hubei University School of Computer Science Wuhan University

In recent years, unsupervised multiplex graph representation learning(UMGRL) has received increasing research interest, which aims to learn discriminative node features from the multiplex graphs supervised by data without the guidance of labels. Although these designed UMGRL methods have obtained great success in various graph-related tasks, most existing UMGRL models still have the following issues: highly depending on complex self-supervised strategies(i.e., data augmentation,pretext tasks, and negative pairs sampling), restricted receptive fields, and only aggregating low-frequency information between nodes. In this paper, we propose a simple unsupervised multiplex graph diffusion network(UMGDN) with the aid of multi-level canonical correlation analysis to solve the above issues. Specifically, we first decouple the feature transform and propagation processes of the graph convolution layer to further improve the generalization of the learnable parameters. And then, we propose adaptive diffusion propagation to capture long-range dependency relationships between nodes, not the local neighborhood interactions. Finally, a multi-level canonical correlation analysis loss on both the feature transform and propagation processes is proposed to maximize the correlation of the same node features from multiple graphs for guiding model optimization. Compared to the existing UMGRL models, our proposed UMGDN does not need to introduce any data augmentation, negative pairs sampling techniques, complex pretext tasks, and also adaptively aggregates the optimal frequency information between nodes to generate more robust node embeddings. Extensive experiments on four popular datasets and two graph-related tasks demonstrate the effectiveness of the proposed method.

关键词： unsupervised multiplex graph representation learning graph neural networks node classification node clustering

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