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Journal of Environmental Sciences 2018年第5期30卷 198-205页

作者： In Chul Kong Kyung Seok Ko Mun Hui Lee Ji Hwoan Lee young-hwan han Department of Environmental Engineering Yeungnam UniversityGyungsan 38541Republic of Korea Geologic Environment Division Korea Institute of Geoscience and Mineral Resources(KIGAM)Daejeon 34132Republic of Korea School of Materials Science and Engineering Yeungnam University Gyungsan 38541Republic of Korea International School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430079China

The toxic effects of the composites of Fe^0 and Cu^0 with different percentages of CNTs were examined based on the activity of bacterial bioluminescence and seed germination. In terms of the EC50 values, the toxic effects of Cu^0 on bacterial bioluminescence and seed germination were approximately 2 and 180 times greater than that of Fe^0, respectively. The toxicity increased with increasing CNT content in the Cu-CNT mixtures for both organisms,whereas opposite results were observed with Fe-CNT mixtures. The mean toxic effects of Cu-CNT（6%） were approximately 1.3–1.4 times greater than that of Cu-CNT（0%）, whereas the toxic effects of Fe-CNT（6%） were approximately 2.1–2.5 times lower than that of Fe-CNT（0%） for both the bioluminescence activity and seed germination. The causes of this phenomenon are unclear at this point. More research will be needed to elucidate the mechanism of the toxicity of nano-mixture materials and the causes of the different patterns of toxicity with Cu-and Fe-CNT mixtures.

关键词： Metal-CNT complex Bioluminescence Seed germination Toxic effect

Effect of hexagonal-BN on phase transformation of additive-free Si_3N_4 /SiC nanocomposites prepared from amorphous precursor

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Transactions of Nonferrous Metals Society of China 2013年第2期23卷 420-425页

作者： Alfian NOVIYANTO Dang-Hyok YOON Kyungseok LEE young Moon KIM Doo-In KIM young-Keun JEONG Kwang Ho KIM Sehun KWON young-hwan han School of Materials Science and Engineering Yeungnam University Gyeongsan 712-749 Korea National Core Research Center for Hybrid Materials Solution Pusan National University Samsung Mobile Display Korea

Si3N4/SiC nanocomposites are well known and attractive for advanced ceramic applications due to excellent mechanlcal and thermal properties, which make them suitable for use in turbine engines, heat exchangers, and other sophisticated applications. However, without the presence of additives, the fabrication of Si3N4/SiC composites is difficult. The additives form a liquid phase during sintering and facilitate the densification of the composite. However, the additives present a drawback at high temperatures since they decrease the mechanical properties of the composites. Recently, Si3N4/SiC composites were fabricated via the polymer precursor route without any additives, using electric field assisted sintering （EFAS）. In this study, fully densified Si3N4/SiC nanocomposites incorporating hexagonal-BN were successfully fabricated by hot pressing without any additives at 1700 ℃ for 2 h under vacuum at a pressure of 50 MPa （via the amorphous precursor route）. Moreover, the incorporation of additives and h-BN is found to decrease the content of SiC. The phase transformation, densification, microstructure, and mechanical properties were discussed and presented.

关键词： Si3N4/SiC hot pressing hexagonal-BN additives sintering

Preparation and applications of calcium ferrite as a functional material:A review

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 292-310页

作者： Xiuli han Bowen Duan Lei Liu Shilong Fang Weiwei Wang College of Mining Engineering North China University of Science and TechnologyTangshan 063210China Collaborative Innovation Center of Green Development and Ecological Restoration of Mineral Resources of Hebei Province Tangshan 063210China Key Laboratory of Mining Development and Security Technology of Hebei Province Tangshan 063210China

Calcium ferrite(CF)is recognized as a potential green and efficient functional material because of its advantages of magnetism,electrochemistry,catalysis,and biocompatibility in the fields of materials chemistry,environmental engineering,and ***-fore,the obtained research results need to be systematically summarized,and new perspectives on CF and its composite materials need to be *** on the presented studies of CF and its composite materials,the types and structures of the crystal are *** addition,the current application technologies and theoretical mechanisms with various properties in different fields are ***,the various preparation methods of CF and its composite materials are elaborated in *** importantly,the advantages and disadvantages of the synthesis methods of CF and its composite materials are discussed,and the existing problems and emerging challenges in practical production are ***,the key future research directions of CF and its composite materials have been prospected from the potential application technologies to provide references for its synthesis and efficient utilization.

关键词： calcium ferrite mineral functional materials preparation application perspectives

Microstructural evolution during the progressive transformation-induced plasticity effect in a Fe-0.1C-5Mnmedium manganese steel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 369-379页

作者： Mei Zhang Wenhao Li Yangfei Chen Yang Jiang Xiaofei Guo han Dong School of Materials Science and Engineering Shanghai UniversityShanghai 200444China State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai 200444China

The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel(Fe-0.10C-5Mn)was investigated during uniaxial tensile ***-situ observations under scanning electron microscopy,transmission electron microscopy,and X-ray diffraction analysis were conducted to characterize the progressive transformation-induced plasticity process and associated fracture initiation *** findings were discussed with the local strain measurements via digital image *** results indicated that Lüders band formation in the steel was limited to 1.5%strain,which was mainly due to the early-stage martensitic phase transformation of a very small amount of the less stable large-sized retained austenite(RA),which led to localized stress concentrations and strain hardening and further retardation of *** small-sized RA exhibited high stability and progressively transformed into martensite and contributed to a stably extended Portevin-Le Chatelier *** volume fraction of RA gradually decreased from 26.8%to 8.2%prior to *** the late deformation stage,fracture initiation primarily occurred at the austenite/martensite and ferrite/martensite interfaces and the ferrite phase.

关键词： medium-Mn steel retained austenite progressive transformation-induced plasticity effect local strain fracture initiation

Fabrication of Near Net Shape Metallic Foam via Plaster Mould

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Journal of Materials Science & Technology 2008年第3期24卷 335-339页

作者： young-hwan Song hwan-Goo Seon Soo-han Parka Min-Jae Jeong Bo-young Hur i-Cube Center School of Nano and Advanced Materials EngineeringGyeongsang National University ERIC School of Nano and Advanced Materials EngineeringGyeongsang National University

Fabrication characteristics are unstable in direct foaming method. Therefore, most of near net-shape metallic foams are produced, and investigated by powder metallurgy. Direct foaming method, however, has many benefits （i.e. reduce the unit cost of goods and fabrication process etc.） to fabrication of metallic foams. In this article, the fabrication characteristic of near net-shape metallic foams by direct foaming method was evaluated. Al and Plaster was used for base material and mould material respectively. Ca and TiH2 were added to molten Al as thickening and blowing agent for stable condition of bubbles. Thickening time was about 10 min with a stirring speed of 600 r/min. Foaming time was 30-120 s for evaluation of the optimum foaming condition. Amount of agent was selected by pre-experimental data. Porosity of near net-shape goods was measured by Archimedes method. On the other hand, it seems that increasing poring time and thickening agent make the poor porosity

关键词： Metal foam Near net shape foam Porosity

Structural stability estimation of whirling unit

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中国有色金属学会会刊：英文版 2009年第B9期19卷 202-208页

作者： Son-Jae hwan han-Chang WOO Lee-Sang RYONG Lee-young MOON Daegu Machinery Institute of Component & Materials Foundation Department of Automobile Yeungnam College of Science & Technology Department of Mechanical Engineering Kyung pook National University

Whirling is a cutting process in which a series of cutting edges on whirling ring remove material by turning over a rotating workpiece. In this study static and dynamic stability of whirling unit was estimated by using ADAMS and NASTRAN softwares. Each maximum force acting on the bearing attached to the spindle assembly and the cutting tool attached to the whirling ring with the rotating speed of 6 000 r/min was 235 N and 902 N respectively. The maximum stress of 0.74 MPa on the base frame is far smaller than the yield strength of 282 MPa. The calculated natural frequency of 148 Hz of the system is far from the frequency of the driving speed of 6 000 r/min. The experimentally obtained maximum cutting force of 792 N is smaller than that of calculated value. And the experimentally obtained natural frequency of 118 Hz is beyond the driving speed of 6000 r/min. From above results it can be judged that the whirling system is statically and dynamically stable.

关键词：旋转工件稳定性评价 NASTRAN软件动态稳定性结构单元固有频率行车速度

Self-expandable metal stents for choledocholithiasis in Billroth II gastrectomy patients

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Hepatobiliary & Pancreatic Diseases International 2018年第6期17卷 546-552页

作者： Min-Gui han Eunae Cho Chang-hwan Park Chung-hwan Jun Seon-young Park Division of Gastroenterology Department of Internal MedicineChonnam National University Hospital42Jaebong-roDong-KuGwangju 61482Korea

Background: Efficient ampullary intervention is essential for endoscopic retrograde cholangiopancreatography(ERCP) in patients with a prior Billroth II gastrectomy. We retrospectively evaluated the safety and effectiveness of ampullary intervention using fully covered self-expandable metal stents(FCSEMSs) for the management of common bile duct(CBD) stones in a subset of patients with a history of Billroth II gastrectomy. Methods: This retrospective analysis involved patients with a prior Billroth II gastrectomy who underwent ampullary intervention with FCSEMSs for the management of CBD stones. The factors associated with FCSEMSs placement, treatment success, and procedural complications were analyzed. Results: A group of 15 patients(10 males; median age, 78 years) underwent biliary metal stent placement for high degree of CBD angulation(6), small or flat papilla with unclear margin(5), current use of double antiplatelet agents or an anticoagulant(2), unwanted instrumentation of the cystic duct(1), and insecure position of the scope(1). Ampullary intervention with FCSEMSs was successful in all patients. After dilating the ampulla of Vater and building a durable conduit with FCSEMSs immediately, CBD stones were removed successfully from all patients in a single session. A mild post-ERCP pancreatitis occurred in one patient, who recovered without complications. Conclusion: Ampullary intervention with FCSEMSs is safe and effective for the management of CBD stones in a subset of patients with a history of Billroth II gastrectomy.

关键词： Common bile duct stone Endoscopic retrograde cholangiopancreatography Stent placement Stone extraction

Fanlian Huazhuo formula:A promising therapeutic approach for metabolic associated steatotic liver disease

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World Journal of Gastroenterology 2025年第1期31卷 167-171页

作者： Chun-han Cheng Wen-Rui Hao Tzu-Hurng Cheng Department of Medical Education Linkou Chang Gung Memorial HospitalTaoyuan 33305Taiwan Division of Cardiology Department of Internal MedicineShuang Ho HospitalMinistry of Health and WelfareTaipei Medical UniversityNew Taipei 23561Taiwan Division of Cardiology Department of Internal MedicineSchool of MedicineCollege of MedicineTaipei Medical UniversityTaipei 11002Taiwan Department of Biochemistry School of MedicineCollege of MedicineChina Medical UniversityTaichung 404328Taiwan

This article reviews the study,“Fanlian huazhuo formula alleviates high-fat-dietinduced nonalcoholic fatty liver disease by modulating autophagy and lipid synthesis signaling pathway”published in the World Journal of *** study explores the therapeutic potential of Fanlian Huazhuo formula(FLHZF)in treating metabolic-associated steatotic liver disease(MASLD),demonstrating that FLHZF reduces lipid accumulation,oxidative stress,and liver injury in MASLD models by modulating key signaling pathways involved in lipid metabolism and *** editorial emphasizes the potential of FLHZF as a treatment for MASLD and calls for further research to verify its clinical efficacy.

关键词： Fanlian Huazhuo formula Metabolic associated steatotic liver disease Autophagy Lipid metabolism Oxidative stress

Crystallization Modulation and Holistic Passivation Enables Efficient Two‑Terminal Perovskite/CuIn(Ga)Se_(2)Tandem Solar Cells

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Nano-Micro Letters 2025年第1期17卷 205-215页

作者： Cong Geng Kuanxiang Zhang Changhua Wang Chung Hsien Wu Jiwen Jiang Fei Long Liyuan han Qifeng han Yi‑Bing Cheng Yong Peng State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070People’s Republic of China Triumph Photovoltaic Materials Co. Ltd.No.1001 Yannan AvenueHigh‑Tech Development DistrictBengbuAnhui 233000People’s Republic of China College of Materials Science and Engineering Guilin University of TechnologyGuilin 541004People’s Republic of China State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

Two-terminal(2-T)perovskite(PVK)/CuIn(Ga)Se_(2)(CIGS)tandem solar cells(TSCs)have been considered as an ideal tandem cell because of their best bandgap matching regarding to Shockley–Queisser(S–Q)***,the nature of the irregular rough morphology of commercial CIGS prevents people from improving tandem device *** this paper,D-homoserine lactone hydrochloride is proven to improve coverage of PVK materials on irregular rough CIGS surfaces and also passivate bulk defects by modulating the growth of PVK *** addition,the minority carriers near the PVK/C60 interface and the incompletely passivated trap states caused interface recombination.A surface reconstruction with 2-thiopheneethylammonium iodide and N,N-dimethylformamide assisted passivates the defect sites located at the surface and grain ***,LiF is used to create this field effect,repelling hole carriers away from the PVK and C60 interface and thus reducing *** a result,a 2-T PVK/CIGS tandem yielded a power conversion efficiency of 24.6%(0.16 cm^(2)),one of the highest results for 2-T PVK/CIGS TSCs to our *** validation underscores the potential of our methodology in achieving superior performance in PVK/CIGS tandem solar cells.

关键词： PVK/CIGS TSCs Irregular rough surfaces Modulating the growth PVK/C60 interface recombination

Potential role of tanycyte-derived neurogenesis in Alzheimer's disease

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Neural Regeneration Research 2025年第6期20卷 1599-1612页

作者： Guibo Qi han Tang Jianian Hu Siying Kang Song Qin Department of Anatomy Histologyand EmbryologySchool of Basic Medical SciencesFudan UniversityShanghaiChina State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science Fudan UniversityShanghaiChina

Tanycytes, specialized ependymal cells located in the hypothalamus, play a crucial role in the generation of new neurons that contribute to the neural circuits responsible for regulating the systemic energy balance. The precise coordination of the gene networks controlling neurogenesis in naive and mature tanycytes is essential for maintaining homeostasis in adulthood. However, our understanding of the molecular mechanisms and signaling pathways that govern the proliferation and differentiation of tanycytes into neurons remains limited. This article aims to review the recent advancements in research into the mechanisms and functions of tanycyte-derived neurogenesis. Studies employing lineage-tracing techniques have revealed that the neurogenesis specifically originating from tanycytes in the hypothalamus has a compensatory role in neuronal loss and helps maintain energy homeostasis during metabolic diseases. Intriguingly,metabolic disorders are considered early biomarkers of Alzheimer's disease. Furthermore,the neurogenic potential of tanycytes and the state of newborn neurons derived from tanycytes heavily depend on the maintenance of mild microenvironments, which may be disrupted in Alzheimer's disease due to the impaired blood–brain barrier ***, the specific alterations and regulatory mechanisms governing tanycyte-derived neurogenesis in Alzheimer's disease remain unclear. Accumulating evidence suggests that tanycyte-derived neurogenesis might be impaired in Alzheimer's disease, exacerbating neurodegeneration. Confirming this hypothesis, however, poses a challenge because of the lack of long-term tracing and nucleus-specific analyses of newborn neurons in the hypothalamus of patients with Alzheimer's disease. Further research into the molecular mechanisms underlying tanycyte-derived neurogenesis holds promise for identifying small molecules capable of restoring tanycyte proliferation in neurodegenerative diseases. This line of investigation could pro

关键词： Alzheimer's disease blood–brain barrier ependymoglial cells hypothalamus metabolic diseases neural stem cells neurogenesis neuroinflammatory diseases neurons tanycyte