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Fabrication and properties of lightweight zirconia with fine closed porosity

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Journal of Iron and Steel Research International 2024年第6期31卷 1449-1458页

作者： Yi-bo Zhang Hua-zhi Gu lv-ping Fu Ao Huang Mei-je Zhang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

Lightweight refractory materials with thermal insulation properties and erosion resistance are advantageous for hightemperature *** zirconia refractories were prepared using starch as a pore-forming agent,basic magnesium carbonate as a stabilizer,and nano-zirconia as an *** effects of the nano-zirconia content on the pore and thermal insulation properties of the lightweight zirconia refractories were investigated based on the porosity,phase composition,microstructure,and thermal ***-zirconia was shown to have a high surface energy,and its addition effectively increased the driving force for sintering,reduced the sintering temperature,and promoted the sintering reaction,thereby reducing the apparent porosity and improving the density of the prepared *** to the superplasticity of nano-zirconia,the surface stress caused plastic deformation between particles,which increased the migration rate of grain boundaries and trapped more gas inside the material before it diffused to the surface,thereby enhancing the closed porosity of the *** presence of closed pores could extend the thermal conduction path,decrease the conduction rate,and hinder the conduction effect to effectively reduce the thermal conductivity of the *** a nano-zirconia content of 0.75 wt.%,the prepared lightweight zirconia had the highest closed porosity and the lowest thermal *** apparent porosity,closed porosity,and total porosity of the material were 2.8%,7.0%,and 9.8%,respectively,and the thermal conductivity at 800℃was 1.37 W m^(-1)k^(-1).

关键词： Sintering Nano-zirconia Closed pore:Thermal conductivity Refractory material

Anti-infective immune functions of type IV interferon in grass carp(Ctenopharyngodon idella):A novel antibacterial and antiviral interferon in lower vertebrates

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Zoological Research 2024年第5期45卷 972-982页

作者： Yuchen Liu Wentao Zhu Yanqi Zhang Jingjing Zhang Maolin lv Jianguo su Hubei Hongshan Laboratory College of FisheriesHuazhong Agricultural UniversityWuhanHubei 430070China Laboratory for Marine Biology and Biotechnology Qingdao Marine Science and Technology CenterQingdaoShandong 266237China

Type IV interferon(IFN-υ)is a recently discovered cytokine crucial for host defense against viral ***,the role and mechanisms of IFN-υin bacterial infections remain *** study investigated the antibacterial and antiviral functions and mechanisms of grass carp(Ctenopharyngodon idella)IFN-υ(CiIFN-υ)both in vivo and in *** CiIFN-υgene was first identified and characterized in grass ***,the immune expression of CiIFN-υsignificantly increased following bacterial challenge,indicating its response to bacterial *** eukaryotic recombinant expression plasmid of CiIFN-υwas then constructed and transfected into fathead minnow(FHM)*** were collected and incubated with four bacterial strains,followed by plate spreading and colony *** indicated that CiIFN-υexhibited more potent antibacterial activity against gram-negative bacteria compared to gram-positive bacteria and aggregated gram-negative bacteria but not gram-positive *** vivo experiments further confirmed the antibacterial function,showing high survival rates,low tissue edema and damage,reduced tissue bacterial load,and elevated proinflammatory response at the early stages of bacterial *** addition,the antiviral function of CiIFN-υwas confirmed through in vitro and in vivo experiments,including crystal violet staining,survival rates,tissue viral burden,and reverse transcription-quantitative real-time polymerase chain reaction(RT-qPCR).This study highlights the antibacterial function and preliminary mechanism of IFN-υ,demonstrating that IFN-υpossesses dual functions against bacterial and viral infections.

关键词： Grass carp(Ctenopharyngodon idella) IFN-υ Bactericidal activity Antiviral activity Antimicrobial immunity

Cone-beam computed tomography noise reduction method based on U-Net with convolutional block attention module in proton therapy

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Nuclear Science and Techniques 2024年第7期35卷 89-100页

作者： Xing-Yue Ruan Xiu-Fang Li Meng-Ya Guo Mei Chen Ming lv Rui Li zhi-Ling Chen Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai201800China University of Chinese Academy of Sciences Beijing100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai201210China Department of Radiation Oncology Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai200025China Shanghai Key Laboratory of Proton therapy Shanghai201801China

Cone-beam computed tomography(CBCT) is mostly used for position verification during the treatment process. However,severe image artifacts in CBCT hinder its direct use in dose calculation and adaptive radiation therapy re-planning for proton therapy. In this study, an improved U-Net neural network named CBAM-U-Net was proposed for CBCT noise reduction in proton therapy, which is a CBCT denoised U-Net network with convolutional block attention modules. The datasets contained 20 groups of head and neck images. The CT images were registered to CBCT images as ground truth. The original CBCT denoised U-Net network, sCTU-Net, was trained for model performance comparison. The synthetic CT(SCT) images generated by CBAM-U-Net and the original sCTU-Net are called CBAM-SCT and U-Net-SCT images, respectively. The HU accuracies of the CT, CBCT, and SCT images were compared using four metrics: mean absolute error(MAE), root mean square error(RMSE), peak signal-to-noise ratio(PSNR), and structure similarity index measure(SSIM). The mean values of the MAE, RMSE, PSNR, and SSIM of CBAM-SCT images were 23.80 HU, 64.63 HU, 52.27 dB, and 0.9919, respectively,which were superior to those of the U-Net-SCT images. To evaluate dosimetric accuracy, the range accuracy was compared for a single-energy proton beam. The γ-index pass rates of a 4 cm × 4 cm scanned field and simple plan were calculated to compare the effects of the noise reduction capabilities of the original U-Net and CBAM-U-Net on the dose calculation results. CBAM-U-Net reduced noise more effectively than sCTU-Net, particularly in high-density tissues. We proposed a CBAM-U-Net model for CBCT noise reduction in proton therapy. Owing to the excellent noise reduction capabilities of CBAM-U-Net, the proposed model provided relatively explicit information regarding patient tissues. Moreover, it maybe be used in dose calculation and adaptive treatment planning in the future.

关键词： Proton therapy Cone-beam CT CBAM-U-Net γ-index

Microstructure and Hot Tearing Sensitivity Simulation and Parameters Optimization for the Centrifugal Casting of Al-Cu Alloy

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Computers, Materials & Continua 2024年第8期80卷 2873-2895页

作者： Xueli He Shengkun lv Ruifeng Dou Yanying Zhang Junsheng Wang Xunliang Liu zhi Wen School of Energy and Environmental Engineering(SEEE) University of Science and Technology Beijing(USTB)Beijing100083China Advanced Research Institute of Multidisciplinary Science(ARIM) Beijing Institute of Technology(BIT)Beijing100081China

Four typical theories on the formation of thermal tears:strength,liquid film,intergranular bridging,and solidifica-tion shrinkage compensation *** these theories,a number of criteria have been derived for predicting the formation of thermal cracks,such as the stress-based Niyama,Clyne,and RDG(Rapaz-Dreiser-Grimaud)*** this paper,a mathematical model of horizontal centrifugal casting was established,and numerical simulation analysis was conducted for the centrifugal casting process of cylindrical Al-Cu alloy castings to investigate the effect of the centrifugal casting process conditions on the microstructure and hot tearing sensitivity of alloy castings by using the modified RDG hot tearing *** show that increasing the centrifugal rotation and pouring speeds can refine the microstructure of the alloy but increasing the pouring and mold preheating temperatures can lead to an increase in grain *** grain size gradually transitions from fine grain on the outer layer to coarse grain on the inner ***,combined with the modified RDG hot tearing criterion,the overall distribution of the castings’hot tearing sensitivity was *** analysis results indicate that the porosity in the middle region of the casting was large,and hot tearing defects were prone to *** hot tearing tendency on the inner side of the casting was greater than that on the outer *** effects of centrifugal rotation speed,pouring temperature,and preheating temperature on the thermal sensitivity of Al-Cu alloy castings are summarized in this *** study revealed that the tendency of alloy hot cracking decreases with the increase of the centrifugal speed,and the maximum porosity of castings decreases first and then increases with the pouring *** the preheating temperature increases,the overall maximum porosity of castings shows a decreasing trend.

关键词： Centrifugal casting Al-Cu alloy microstructure hot tearing simulation

Current Status and Perspectives of Dual-Atom Catalysts Towards sustainable Energy Utilization

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Nano-Micro Letters 2024年第7期16卷 402-440页

作者： Yizhe Li Yajie Li Hao sun Liyao Gao Xiangrong Jin Yaping Li zhi lv Lijun Xu Wen Liu Xiaoming sun State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science EngineeringCollege of ChemistryBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China Xinjiang Coal Mine Mechanical and Electrical Engineering Technology Research Center Xinjiang Institute of EngineeringUrumqi 830023Xinjiang Uygur Autonomous RegionPeople’s Republic of China

The exploration of sustainable energy utilization requires the imple-mentation of advanced electrochemical devices for efficient energy conversion and storage,which are enabled by the usage of cost-effective,high-performance ***,heterogeneous atomically dispersed catalysts are considered as potential candidates for a wide range of *** to conventional cata-lysts,atomically dispersed metal atoms in carbon-based catalysts have more unsatu-rated coordination sites,quantum size effect,and strong metal-support interactions,resulting in exceptional catalytic *** these,dual-atomic catalysts(DACs)have attracted extensive attention due to the additional synergistic effect between two adja-cent metal *** have the advantages of full active site exposure,high selectiv-ity,theoretical 100%atom utilization,and the ability to break the scaling relationship of adsorption free energy on active *** this review,we summarize recent research advancement of DACs,which includes(1)the comprehensive understanding of the synergy between atomic pairs;(2)the synthesis of DACs;(3)characterization meth-ods,especially aberration-corrected scanning transmission electron microscopy and synchrotron spectroscopy;and(4)electrochemical energy-related *** last part focuses on great potential for the electrochemical catalysis of energy-related small molecules,such as oxygen reduction reaction,CO_(2) reduction reaction,hydrogen evolution reaction,and N_(2) reduction *** future research challenges and opportunities are also raised in prospective section.

关键词： Dual-atom catalysts Synergetic effect Electrocatalysis Oxygen reduction reaction CO_(2)reduction reaction Hydrogen evolution reaction N2 reduction reaction

Epimedin B exhibits pigmentation by increasing tyrosinase family proteins expression,activity,and stability

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Journal of Pharmaceutical Analysis 2024年第1期14卷 69-85页

作者： Chen Hong Yifan Zhang Lili Yang Haoyang Xu Kang Cheng zhi lv Kaixian Chen Yiming Li Huali Wu Department of TCM Chemistry School of PharmacyShanghai University of Traditional Chinese MedicineShanghai200000China Department of Dermatology Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai200000China International Education College Shanghai University of Traditional Chinese MedicineShanghai200000China Shanghai Inoherb Cosmetics Co. Ltd.Shanghai200000China

Epimedin B(EB)is one of the main flavonoid ingredients present in Epimedium brevicornum Maxim.,a traditional herb widely used in *** previous study showed that EB was a stronger inducer of melanogenesis and an activator of tyrosinase(TYR).However,the role of EB in melanogenesis and the mechanism underlying the regulation remain ***,as an extension to our previous investigation,we provide comprehensive evidence of EB-induced pigmentation in vivo and in vitro and elucidate the melanogenesis mechanism by assessing its effects on the TYR family of proteins(TYRs)in terms of expression,activity,and *** results showed that EB increased TYRs expression through microphthalmia-associated transcription factor-mediated p-Akt(referred to as protein kinase B(PKB))/glycogen synthase kinase 3β(GSK3β)/β-catenin,p-p70 S6 kinase cascades,and protein 38(p38)/mitogen-activated protein(MAP)kinase(MAPK)and extracellular regulated protein kinases(ERK)/MAPK pathways,after which EB increased the number of melanosomes and promoted their maturation for melanogenesis in melanoma cells and human primary melanocytes/skin ***,EB exerted repigmentation by stimulating TYR activity in hydroquinone-and N-phenylthiourea-induced TYR inhibitive models,including melanoma cells,zebrafish,and ***,EB ameliorated monobenzone-induced depigmentation in vitro and in vivo through the enhancement of TYRs stability by inhibiting TYR misfolding,TYR-related protein 1 formation,and retention in the endoplasmic reticulum and then by downregulating the ubiquitination and proteolysis *** data conclude that EB can target TYRs and alter their expression,activity,and stability,thus stimulating their pigmentation function,which might provide a novel rational strategy for hypopigmentation treatment in the pharmaceutical and cosmetic industries.

关键词： Epimedin B Melanosome Tyrosinase Melanogenesis

High-pressure capacity expansion and water injection mechanism and indicator curve model for fractured-vuggy carbonate reservoirs

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PETROLEUM 2024年第3期10卷 511-519页

作者： Chen, Lixin Jia, Chengzao Zhang, Rujie Yue, Ping Jiang, Xujian Wang, Junfang su, Zhou Xiao, Yun lv, Yuan China Univ Petr Inst Unconvent Oil & Gas Sci & Technol Beijing 102249 Peoples R China Southwest Petr Univ State Key Lab Reservoir Geol & Dev Chengdu 610500 Peoples R China Tarim Oil field Co PetroChina Korla 841000 Peoples R China

Water injection for oil displacement is one of the most effective ways to develop fractured-vuggy carbonate reservoirs. With the increase in the number of rounds of water injection, the development effect gradually fails. The emergence of high-pressure capacity expansion and water injection technology allows increased production from old wells. Although high-pressure capacity expansion and water injection technology has been implemented in practice for nearly 10 years in fractured-vuggy reservoirs, its mechanism remains unclear, and the water injection curve is not apparent. In the past, evaluating its effect could only be done by measuring the injection-production volume. In this study, we analyze the mechanism of high-pressure capacity expansion and water injection. We propose a fluid exchange index for high-pressure capacity expansion and water injection and establish a discrete model suitable for high-pressure capacity expansion and water injection curves in fractured-vuggy reservoirs. We propose the following mechanisms: replenishing energy, increasing energy, replacing energy, and releasing energy. The above mechanisms can be identified by the high-pressure capacity expansion and water injection curve of the well HA6X in the Halahatang Oilfield in the Tarim Basin. By solving the basic model, the relative errors of Reservoirs I and II are found to be 1.9% and 1.5%, respectively, and the application of field examples demonstrates that our proposed high-pressure capacity expansion and water injection indicator curve is reasonable and reliable. This research can provide theoretical support for high-pressure capacity expansion and water injection technology in fracture-vuggy carbonate reservoirs.

关键词： Fractured-vuggy carbonate reservoirs High-pressure capacity expansion and water injection Mechanism Water injection indicator curve ENHANCED OIL-RECOVERY STRESS SENSITIVITY TARIM BASIN FIELD

Decade Milestone Advancement of Defect-Engineered g-C_(3)N_(4) for Solar Catalytic Applications

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Nano-Micro Letters 2024年第4期16卷 153-218页

作者： Shaoqi Hou Xiaochun Gao Xingyue lv Yilin Zhao Xitao Yin Ying Liu Juan Fang Xingxing Yu Xiaoguang Ma Tianyi Ma Dawei su School of Mathematical and Physical Sciences Faculty of ScienceUniversity of Technology Sydney(UTS)SydneyNSW 2007Australia Laboratory of Plasma and Energy Conversion School of Physics and Optoelectronic EngineeringLudong University186 Middle Hongqi RoadYantai 264025People’s Republic of China School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083People’s Republic of China Department of Chemistry The University of Tokyo7‑3‑1 HogoBunkyoTokyoJapan School of Science STEM CollegeRMIT UniversityMelbourneVIC 3000Australia

Over the past decade, graphitic carbon nitride(g-C_(3)N_(4)) has emerged as a universal photocatalyst toward various sustainable carbo-neutral technologies. Despite solar applications discrepancy, g-C_(3)N_(4) is still confronted with a general fatal issue of insufficient supply of thermodynamically active photocarriers due to its inferior solar harvesting ability and sluggish charge transfer dynamics. Fortunately, this could be significantly alleviated by the “all-in-one” defect engineering strategy, which enables a simultaneous amelioration of both textural uniqueness and intrinsic electronic band structures. To this end, we have summarized an unprecedently comprehensive discussion on defect controls including the vacancy/non-metallic dopant creation with optimized electronic band structure and electronic density, metallic doping with ultraactive coordinated environment(M–N_(x), M–C_(2)N_(2), M–O bonding), functional group grafting with optimized band structure, and promoted crystallinity with extended conjugation π system with weakened interlayered van der Waals interaction. Among them, the defect states induced by various defect types such as N vacancy, P/S/halogen dopants, and cyano group in boosting solar harvesting and accelerating photocarrier transfer have also been emphasized. More importantly, the shallow defect traps identified by femtosecond transient absorption spectra(fs-TAS) have also been highlighted. It is believed that this review would pave the way for future readers with a unique insight into a more precise defective g-C_(3)N_(4) “customization”, motivating more profound thinking and flourishing research outputs on g-C_(3)N_(4)-based photocatalysis.

关键词： Defect engineering g-C_(3)N_(4) Electronic band structures Photocarrier transfer kinetics Defect states

Mechanism research progress on transition metal compound electrode materials for supercapacitors

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Rare Metals 2024年第9期43卷 4076-4098页

作者： zhi-Hui Xu Xue-Lei Li Qing-Wen Li Kai lv Jing-Shun Liu Xiu-Kun Hang Aruuhan Bayaguud School of Materials Science and Engineering Inner Mongolia University of Technology School of Materials Science and Engineering Tianjin University of Technology College of Chemistry and Chemical Engineering Inner Mongolia University

supercapacitors(SCs) have remarkable energy storage capabilities and have garnered considerable interest due to their superior power densities and ultra-long cycling characteristics. However, their comparatively low energy density limits their extensive application in large-scale commercial applications. Electrode materials directly affect the performance of SCs. Thus, the development of cutting-edge electrode materials and modification of their morphological and structural properties are vital for advancing the performance of SCs. Transition metal compounds have a high specific capacity and good cycling durability, making them the most promising electrode active materials for high-energy density SCs. Nevertheless,their inadequate conductivity, unfavorable ion diffusion rates, substantial volume expansion and phase transitions during charging and discharging are obstacles to their stable and efficient integration into SCs. To address these challenges, this study provides a comprehensive summary of the current advancements in transition metal nanomaterials as electrode materials for SCs, an overview of the current research status, and the prevailing ***, this study highlights synthetic techniques and management strategies for electrode materials derived from transition metal compounds, targeting the resolution of the aforementioned challenges. Finally, a concise discussion is provided on the future directions of SC development, with an emphasis on the utilization of transition metal compound electrode materials.

关键词： Electrodes