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Numerical simulation of microstructure and microporosity morphology in directional solidification of aluminum-copper alloys:Effect of copper content and withdrawal rate

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China Foundry 2025年第1期22卷 33-44页

作者： Wei yuan Hai-dong Zhao Xu Shen chun Zou yuan Liu Qing-yan Xu National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510640China Key Laboratory for Advanced Materials Processing Technology(Ministry of Education) Tsinghua UniversityBeijing 100084China

Microporosity formed in the solidification process of Al alloys is detrimental to the alloy properties.A two-dimensional cellular automaton(CA)model was developed to simulate the microstructure and microporosity formation in Al-Cu alloys,considering variations in Cu content and solidification *** results indicate that the Cu content primarily influences the growth of *** validate the model,directional solidification experiments were conducted on Al-Cu alloys with varing Cu contents and withdrawal *** experimental results of dendrites and microporosity characteristics agree well with the predictions from the developed model,thus confirming the validity of the *** alloy’s liquidus temperature,dendrite morphology,and hydrogen saturation solubility arising from different Cu contents have significant effects on microporosity *** withdrawal rate primarily affects the nucleation of hydrogen microporosity by altering cooling rates and dendritic growth rates,resulting in different microporosity characteristics.

关键词： microporosity dendrites cellular automaton Al-Cu alloys directional solidification

维普期刊数据库

3D morphology of crab(Macrophthalmus japonicus) burrows from the Pearl River Delta front,China:The physicochemical factors,with implications for the rock record

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Journal of Palaeogeography 2025年第1期14卷 203-220页

作者： yuan-yuan Wang Ya-Bin Zhang song-Lin Gou Guo-Cheng Zhang Institute of Resource and Environment Henan Polytechnic University Henan International Joint Laboratory of Biogenic Traces and Sedimentary Minerals Henan Polytechnic University

Neoichnological characterization of modern depositional settings addresses the response of benthic animals to ecological conditions and their fluctuations, usually on a relatively short time scale. In this way, analogue models for interpretation of sedimentary strata in the geological record can be *** japonicus(De Haan, 1835), a crab, is commonly found in the Pearl River Delta front of southern China. The burrows of M. japonicus are vertical or inclined, I-, U-, Y-, J-and L-shaped tubes, and these are imaged in 7.5-cm-diameter sediment cores. The cores were studied by X-ray radiography, computed tomography, and VG Studio MAX reconstruction to obtain three-dimensional images for elaborate morphological study. This crab's burrows are analogous to the trace fossil Psilonichnus. Several environmental parameters, i.e., sediment grain size and its total organic carbon(TOC) content, and turbidity and salinity of water, have been measured. The results indicated that M. japonicus prefers to live in mesohaline water with turbidity levels of 20-170 NTU, where bioturbation is more abundant. It prefers to occur in mud and silty sand substrates, with TOC content decreasing as particle size increases. The sedimentary environment, grain size and ichnofacies of analogical trace fossils Psilonichnus are discussed which supports the interpretation that Psilonichnus is a good indicator of delta front environments.

关键词： Neoichnology Macrophthalmus japonicus Pearl River Delta front Physicochemical factor

Stochastic Augmented-Based Dual-Teaching for Semi-Supervised Medical Image Segmentation

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Computers, Materials & Continua 2025年第1期82卷 543-560页

作者： Hengyang Liu Yang yuan Pengcheng Ren Chengyun song Fen Luo School of Computer Science and Engineering Chongqing University of TechnologyChongqing400054China College of Artificial Intelligence Chongqing Technology and Business UniversityChongqing400067China

Existing semi-supervisedmedical image segmentation algorithms use copy-paste data augmentation to correct the labeled-unlabeled data distribution ***,current copy-paste methods have three limitations:(1)training the model solely with copy-paste mixed pictures from labeled and unlabeled input loses a lot of labeled information;(2)low-quality pseudo-labels can cause confirmation bias in pseudo-supervised learning on unlabeled data;(3)the segmentation performance in low-contrast and local regions is less than *** design a Stochastic Augmentation-Based Dual-Teaching Auxiliary Training Strategy(SADT),which enhances feature diversity and learns high-quality features to overcome these *** be more precise,SADT trains the Student Network by using pseudo-label-based training from Teacher Network 1 and supervised learning with labeled data,which prevents the loss of rare labeled *** introduce a bi-directional copy-pastemask with progressive high-entropy filtering to reduce data distribution disparities and mitigate confirmation bias in *** the mixed images,Deep-Shallow Spatial Contrastive Learning(DSSCL)is proposed in the feature spaces of Teacher Network 2 and the Student Network to improve the segmentation capabilities in low-contrast and local *** this procedure,the features retrieved by the Student Network are subjected to a random feature perturbation *** two openly available datasets,extensive trials show that our proposed SADT performs much better than the state-ofthe-art semi-supervised medical segmentation *** only 10%of the labeled data for training,SADT was able to acquire a Dice score of 90.10%on the ACDC(Automatic Cardiac Diagnosis Challenge)dataset.

关键词： Semi-supervised medical image segmentation contrastive learning stochastic augmented

Study on the hydrogen absorption properties of a YGdTbDyHo rare-earth high-entropy alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 127-135页

作者： Tongyue Li Ziliang Xie Wenjiao Zhou Huan Tong Dawen Yang Anjia Zhang yuan Wu Xiping song State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Whole Win(Beijing)Materials Sci.&Tech.Co. Ltd.Beijing 100083China

This study investigated the microstructure and hydrogen absorption properties of a rare-earth high-entropy alloy(HEA),*** indicated that the YGdTbDyHo alloy had a microstructure of equiaxed grains,with the alloy elements distributed *** hydrogen absorption,the phase structure of the HEA changed from a solid solution with an hexagonal-close-packed(HCP)structure to a high-entropy hydride with an faced-centered-cubic(FCC)structure without any secondary phase *** alloy demonstrated a maximum hydrogen storage capacity of 2.33 H/M(hydrogen atom/metal atom)at 723 K,with an enthalpy change(ΔH)of-141.09 kJ·mol^(-1)and an entropy change(ΔS)of-119.14 J·mol^(-1)·K^(-1).The kinetic mechanism of hydrogen absorption was hydride nucleation and growth,with an apparent activation energy(E_(a))of 20.90 kJ·mol^(-1).Without any activation,the YGdTbDyHo alloy could absorb hydrogen quickly(180 s at 923 K)with nearly no incubation period *** reason for the obtained value of 2.33 H/M was that the hydrogen atoms occupied both tetrahedral and octahedral *** results demonstrate the potential application of HEAs as a high-capacity hydrogen storage material with a large H/M ratio,which can be used in the deuterium storage field.

关键词： rare-earth high-entropy alloy hydrogen absorption capacity pressure–composition–temperature curves kinetics

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N-Benzyl arylamide derivatives as novel and potent tubulin polymerization inhibitors against gastric cancers: Design,structure–activity relationships and biological evaluations

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Chinese Chemical Letters 2025年第2期36卷 256-261页

作者： Jian song Shenghui Wang Qiuge Liu Xiao Wang Shuo yuan Hongmin Liu Saiyang Zhang School of Basic Medical Sciences Zhengzhou University Children's Hospital Affiliated to Zhengzhou University Henan Children's Hospital Zhengzhou Children's Hospital School of Pharmaceutical Sciences Institute of Drug Discovery & Development Key Laboratory of Advanced Drug Preparation Technologies (Ministry of Education) Zhengzhou University State Key Laboratory of Esophageal Cancer Prevention & Treatment

In this work,we employed a ring-opening strategy to develop a series of novel N-benzyl arylamide derivatives as tubulin polymerization ***,13n （MY-1388） exhibited remarkable antiproliferative potency on fifteen human cancer cell lines,with half maximal inhibitory concentration (IC50)values ranging from 8 nmol/L to 48 nmol/***,13n effectively suppressed tubulin polymerization by targeting the colchicine-binding site (IC50=0.62μmol/L).13n also exhibited significant inhibition of cell colony formation,as well as displayed potent effects on inducing G2/M phase cell cycle arrest and promoting ***,13n exhibited enhanced and adequate liver microsomal stability in human and rat liver microsomes,and also exhibited a moderate half-life (T1/2=0.938 h) in ***,13n demonstrated effective antitumor effects in vivo in suppressing tumor growth in the MGC-803xenograft model (tumor growth inhibition （TGI） value was 76.4%at the dosage of 30 mg kg-1day-1)with a good safety ***,these results revealed that 13n represents a promising tubulin polymerization inhibitor that deserves further investigation for its efficacy in treating gastric cancers.

关键词： Antiproliferative activities CA-4 Colchicine binding site N-Benzyl arylamide Tubulin

Effect of graphene addition on activation and kinetic properties of La-Mg-Ni-based hydrogen storage alloys

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Journal of Iron and Steel Research International 2025年第1期32卷 227-238页

作者： Dian-chen Feng chun-ling Zheng Zhi-yuan Zhao Dong-sheng Zhou Hui-ping Ren Yang-huan Zhang School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou014010Inner MongoliaChina Collaborative Innovation Center of Integrated Exploitation of Bayan Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou014010Inner MongoliaChina Department of Functional Material Research China Iron and Steel Research Institute GroupBeijing100081China

The La_(1.7)Pr_(0.3)Mg_(16)Ni hydrogen storage alloy was prepared by medium-frequency induction melting,and then the composite hydrogen storage alloy powder of La_(1.7)Pr_(0.3)Mg_(16)Ni+x wt.%(x=0,2,4,and 6)graphene was prepared by ball milling for 10 *** effect of the addition of graphene on the activation and hydrogen de/absorption properties of La_(1.7)Pr_(0.3)Mg_(16)Ni alloy was *** result demonstrated that these composite alloys were composed of La_(2)Mg_(17),La_(2)Ni_(3),and Mg_(2)Ni *** saturated hydrogen absorption,it was composed of LaH_(3),Mg_(2)NiH_(4),and MgH_(2)phases,while during the dehydrogenation process,it was composed of LaH_(3),Mg,and Mg_(2)Ni *** addition of graphene can help get a more homogeneous granule after ball milling and accelerate the first activation of dehydrogenation/hydrogen *** hydrogen release activation energy of the alloys first decreases and then increases as the graphene content increases from x=0 wt.%to x=6 wt.%.The minimum activation energy of the composite hydrogen storage alloy is 51.22 kJ mol^(-1) when x=4 wt.%.

关键词： La-Mg-Ni alloy Graphene Mechanical ball milling Activation property Dynamic performance

Sensitive visual detection of norfloxacin in water by smartphone assisted colorimetric method based on peroxidase-like active cobalt-doped Fe_(3)O_(4) nanozyme

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Journal of Environmental Sciences 2025年第2期148卷 198-209页

作者： Linchun Nie Shuangying Li Xiaozhong Gao Shuai yuan Guangyu Dong Guojin Tang Denghao song Lutong Bu Qingxiang Zhou College of Chemical Engineering and Environment China University of Petroleum-BeijingBeijing 102249China

Norfloxacin is widely used owing to its strong bactericidal effect on Gram-negative ***,the residual norfloxacin in the environment can be biomagnified via food chain andmay damage the human liver and delay the bone development *** work described a reliable and sensitive smartphone colorimetric sensing system based on cobaltdoped Fe_(3)O_(4) magnetic nanoparticles(Co-Fe_(3)O_(4) MNPs)for the visual detection of *** with Fe_(3)O_(4),Co-Fe_(3)O_(4) MNPs earned more remarkably peroxidase-like activity and TMB(colorless)was rapidly oxidized to oxTMB(blue)with the presence of H_(2)O_(2).Interestingly,the addition of low concentration of norfloxacin can accelerate the color reaction process of TMB,and blue deepening of the solution can be observed with the naked ***,after adding high concentration of norfloxacin,the activity of nanozymewas inhibited,resulting in the gradual fading of the *** on this principle,a colorimetric sensor integrated with smartphone RGB mode was *** visual sensor exhibited good linearity for norfloxacin monitoring in the range of 0.13-2.51μmol/L and 17.5-100μmol/*** limit of visual detectionwas 0.08μmol/*** the actualwater sample analysis,the spiked recoveries of norfloxacin were over the range of 95.7%-104.7%.These results demonstrated that the visual sensor was a convenient and fast method for the efficient and accurate detection of norfloxacin in water,which may have broad application prospect.

关键词： Nanozymes Cobalt-doped Fe3O4 magnetic nanoparticles Visual method Smartphone Norfloxacin

Exploring the HONO source during the COVID-19 pandemic in a megacity in China

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Journal of Environmental Sciences 2025年第3期149卷 616-627页

作者： Mingkai Wang Shenbo Wang Ruiqin Zhang Minghao yuan Yifei Xu Luqi Shang Xinshuai song Xinyuan Zhang Yunxiang Zhang School of Ecology and Environment Zhengzhou UniversityZhengzhou 450000China Research Institute of Environmental Sciences Zhengzhou UniversityZhengzhou 450000China Zhengzhou Ecological Environment Monitoring Center of Henan Province Zhengzhou 450000China College of Chemistry Zhengzhou UniversityZhengzhou 450000China

HONO is a critical precursor of•OH,but its sources are controversial due to its complex formation *** study conducted comprehensive observations in Zhengzhou from April 26 to May 11,*** NO_(x)concentrations were observed during the Covid epidemic period(EP)(10.4±3.0 ppb),compared to the pre-epidemic period(PEP)(12.5±3.8 ppb).The mean HONO concentration during EP(0.53±0.34 ppb)was 0.09 ppb lower than that during PEP(0.62±0.53 ppb).The decrease in HONO concentration during EP came mainly at night due to the reduction in the direct emission(P_(emi))(0.03 ppb/hr),the homogeneous reaction between•OHandNO(P_(OH+NO))(0.02 ppb/hr),and the heterogeneous conversion of NO_(2)on the ground(0.01 ppb/hr).Notably,there was no significant change in daytime HONO *** daytime HONO budget indicated that the primary HONO sources during PEP were the nitrate photolysis(P_(nitrate)),followed by the P_(OH+NO),Pemi,the photo-enhanced reaction of NO_(2)on the ground(P_(ground+hv))and aerosol surface(Paerosol+hv).The primary HONO sources were Pnitrate,POH+NO,P_(emi),and_(Paerosol+hv)during EP,*** missing source has a high correlation with solar radiation,there might be other photo-related HONO sources or the contributions of photosensitized reactions were *** the extremely underestimated cases,HONO production rates fromthe P_(nitrate),P_(ground+hv),and Paerosol+hv increased by 0.17,0.10,and 0.10 ppb/hr during PEP,0.23,0.13,and 0.16 ppb/hr during EP,and P_(nitrate)was still the primary source during both PEP and EP.

关键词： Nitrous acid Nitrogen oxides COVID-19 HONO budget Unknown sources

Crevice corrosion of reinforcing steel in carbonated simulated concrete pore solutions contaminated by chloride

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Journal of Iron and Steel Research International 2025年第1期32卷 293-311页

作者： Peng-peng Wu yuan-pei Gong Shao-hua Zhang Yue-zhong Zhang Bao-sheng Liu Guang-ling song College of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan030024ShanxiChina College of Chemical Engineering and Technology Taiyuan University of Science and TechnologyTaiyuan030024ShanxiChina Department of Ocean Science and Engineering Southern University of Science and TechnologyShenzhen518055GuangdongChina School of Mechanical and Mining Engineering Centre for Advanced Materials Processing and Manufacturing(AMPAM)The University of QueenslandSt LuciaQLD4072Australia State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen UniversityXiamen361005FujianChina

The crevice corrosion of the reinforcing steel in the carbonated simulated concrete pore solutions(SCPSs)containing 0.04 mol/L chloride was *** comparison,the steel without crevice covered on its surface was also *** showed that the crevice corrosion in the uncarbonated SCPS was not triggered and the steel remained passivity by suppressing the anodic dissolution in the crevice *** SCPS was carbonated to have pH values of 10.5 and 11.5,the crevice corrosion was easier to be activated than the widely reported pitting corrosion owing to the rapid oxygen depletion within the crevice,but the crevice corrosion damage might be alleviated to a certain extent due to the relative compact surface film formed inside the *** further carbonation led to the activation dissolution of both the crevice interior and exterior,causing the more serious corrosion *** process of the crevice corrosion was systematically analyzed by combining the electrochemical measurement results and Evens polarization diagram.

关键词： Crevice corrosion Reinforcing steel Carbonation Electrochemical test Rust Evens polarization diagram