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Levels of polycyclic aromatic hydrocarbons in some agricultural, industrial and urban areas along Xiamen coastal waters, China

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Journal of Environmental Sciences 2006年第2期18卷 318-322页

作者： MASKAOUI Khalid HU Zhong ZHOU jun-liang han ya-li Biology Department Shantou University Shantou 515063 China Department of Biology and Environmental Science University of Sussex Falmer Brighton BN1 9QJ UK

An intensive investigation was conducted to study the distribution of polycyclic aromatic hydrocarbons （PAHs）, to show firstly the level of pollution in the agricultural areas and analyses specifically the status of soil polluted by these persistent pollutants in some locations of Xiamen region. Soil samples collected from Jiulong agricultural catchment have been analysed for 16 PAH compounds, using gas chromatography flame ionization detection in order to determine the level of selected PAH components and to identify the factors that may control their distribution and persistence in the area. The main PAHs found in soil samples were the low molecular weight. The total PAHs detected in soil samples ranged from 0.50 to 0.95 μg/g soil. The highest values of PAHs were significantly detected in the orange tree leaves, which range from 236.1 to 249.3 μg/g soil showing recent atmospheric inputs of these volatile pollutants. The distribution of PAHs in vegetable were monitored and indicating that the concentration were high and ranged from 8.24 to 58.87 μg/g. Other sediment samples were also collected and analysed from urban sewage （5.26 μg/g dw）, aquacultural （0.52 μg/g dw） and industrial areas （from 0.62 to 2.09 μg/g dw）, during this investigation. The contamination of Jiulong river estuary and Xiamen Western Sea by PAHs has been then widely justified by wastcwatcr discharges and soil runoffs from these areas. The results, therefore, provide important information on the current contamination status caused by the atmospheric transport and point to the need for urgent actions to stop the release of these hydrocarbons to the environment. The necessity of implementing systematic monitoring of PAHs is also emphasized.

关键词： PAHs soil Jiulong River Estuary Xiamen Western Sea

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干细胞的趋电性迁移及机制

中国组织工程研究 2025年第23期29卷 4984-4992页

作者：韩芳舒晴贾绍辉田峻武汉体育学院运动医学院湖北省武汉市430079 武汉大学中南医院骨科康复科湖北省武汉市430071

背景:随着对干细胞技术研究的深入,如何使其准确归巢成为临床应用中的一大难题。除药物和趋化因子等信号的诱导外,电场也被广泛应用于指导干细胞的定向迁移,并可增强其迁移速度和定向性。目的:旨在分析总结电场对干细胞迁移特性的影响,... 详细信息

背景:随着对干细胞技术研究的深入,如何使其准确归巢成为临床应用中的一大难题。除药物和趋化因子等信号的诱导外,电场也被广泛应用于指导干细胞的定向迁移,并可增强其迁移速度和定向性。目的:旨在分析总结电场对干细胞迁移特性的影响,同时综述可能的作用机制。方法:通过检索Pub Med和中国知网数据库,收集截至2024年3月的相关文献,英文检索词:“stem cells,direct current electric field,pulsed electric field,migration,electric field device,mechanism”;中文检索词:“干细胞,直流电场,脉冲电场,迁移,电场装置,机制”。排除不能获取全文和与主题无关的文献。结果与结论:根据筛选要求共纳入58篇文献,包括中文文献15篇及英文文献43篇。文献以脂肪间充质干细胞、骨髓间充质干细胞、神经干细胞、表皮干细胞、人胚胎干细胞和人诱导性多功能干细胞为研究对象,在迁移装置中研究电场的不同参数对上述干细胞迁移的影响及其机制。(1)电场作为一种简单、无创且稳定的干预方式在指导干细胞定向迁移的过程中起着积极作用;(2)不同类型的干细胞发生趋电性迁移的方向不同,同时大部分干细胞的迁移速度和定向性是随着电场强度增加而增加的;(3)不同的电场装置在观测干细胞迁移时的侧重点不同,可根据实验目的而择优选择相关装置;(4)不同干细胞趋电性迁移的机制不完全相同,多数干细胞迁移过程中有MAPK通路、ROCK活化以及PI3K功能的参与,同时还有其他蛋白质复合物与信号通路参与调控该过程;(5)除电场参数不同之外,细胞本身的衰老情况和培养环境也会对趋电性迁移的结果产生影响。总而言之,电场作为一种影响干细胞迁移特性的重要信号,与其他新兴材料结合在组织工程应用中展现出了一定的潜力,有望在指导干细胞归巢方面发挥更加重要的作用,促进骨组织再生和修复以及神经系统、自身免疫系统以及肿瘤等疾病的研究取得更大的突破。

关键词：干细胞电场趋电性迁移机制归巢效应物理因子电场装置细胞衰老培养环境

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

Pore-scale study of the pressure-sensitive effect of sandstone and its influence on multiphase flows

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Petroleum Science 2019年第2期16卷 382-395页

作者： jun-Jian Li yang Liu ya-jun Gao Bao-yang Cheng han-Qiao Jiang State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum CNOOC Research Institute Co.Ltd

The pressure-sensitive effect on the pore structure of sandstone was investigated using X-ray computed micro-tomography and QEMSCAN quantitative mineral analysis. In a physical simulation study, we extracted the pore network model from digital cores at different confining pressures and evaluated the effect of pressure sensitivity on the multiphase displacement process. In both the pore network model and QEMSCAN scanning, the pore structure was observed to be damaged under a high confining pressure. Due to their different scales, the pores and throats exhibited inhomogeneous changes; further, the throats exhibited a significant variation compared to that exhibited by the pores. Meanwhile, the heterogeneity of the pore structure under the two aforementioned activities was aggravated by the elastic-plastic deformation of the pore *** pressure-sensitive effect increased the proportion of mineral particles, such as quartz(the main component of the core skeleton), and reduced the proportion of clay minerals. The clay minerals were originally attached to the pore walls or interspersed in the pores; however, as the pressure increased, the clay minerals accumulated in the pores resulting in blockage of the pores. While simulating the multiphase displacement process, increasing the confining pressure was observed to severely restrict the flowability of oil and water. This study promises to improve the efficiency of reservoir development in terms of oil and gas exploitation.

关键词： Pressure sensitive - QEMSCAN Micro-CT Pore network model Multiphase flow

Differences in clinical and genetic characteristics between early-and late-onset narcolepsy in a han Chinese cohort

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Neural Regeneration Research 2020年第10期15卷 1887-1893页

作者： Hui Ouyang Fang han Ze-Chen Zhou jun Zhang Department of Clinical Neurology Peking University People’s HospitalBeijingChina Department of Clinical Pulmonology Peking University People’s HospitalBeijingChina Department of Epidemiology and Biostatistics School of Public HealthPeking University Health Science CenterBeijingChina

Early-and late-onset narcolepsy constitutes two distinct diagnostic ***,it is not clear whether symptomology and genetic risk factors differ between early-and late-onset *** study compared clinical data and single-nucleotide polymorphisms(SNPs)between early-and late-onset patients in a large cohort of 899 han Chinese narcolepsy ***,cerebrospinal fluid,and clinical data were prospectively collected from patients,and patients were genotyped for 40 previously reported narcolepsy risk-conferring *** risk scores(GRSs),associations of five different sets of SNPs(GRS1–GRS5)with early-and late-onset narcolepsy,were evaluated using logistic regression and receiver operating characteristic *** sleep latency was significantly shorter in early-onset cases than in late-onset *** severity was greater among late-onset patients,with higher rates of sleep paralysis,hypnagogic hallucinations,health-related quality of life impairment,and concurrent presentation with four or more *** levels did not differ significantly between early-and late-onset *** rs3181077(CCR1/CCR3)and rs9274477(HLA-DQB1)were more prevalent among early-onset *** GRS1(26 SNPs;OR=1.513,95%CI:0.893–2.585;P<0.05)and GRS5(6 SNPs;OR=1.893,95%CI:1.204–2.993;P<0.05)were associated with early-onset narcolepsy,with areas under the receiver operating characteristic curves of 0.731 and 0.732,*** GRS1 nor GRS5 included SNPs in HLA *** results indicate that symptomology and genetic risk factors differ between early-and late-onset *** protocol was approved by the Institutional Review Board(IRB)Panels on Medical Human Subjects at Peking University People’s Hospital,China(approval *** 86)in October 2011.

关键词： case-control studies clinical features genetic association studies genetic load genetic loci genetic phenomena hypothalamic diseases precision medicine risk assessment single nucleotide polymorphism

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

Effect of cerium addition on microstructure and mechanical properties of as-cast high grade knives steel

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Journal of Iron and Steel Research International 2022年第12期29卷 1986-1994页

作者： Xi-ya Qiao Xiao han Zhi-jun He Zhen Zhuang Xin yang Fei-xiong Mao School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina Ningbo Key Laboratory of Marine Protection Materials Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201ZhejiangChina

The carbides and mechanical properties of as-cast high grade knives steel with and without cerium(Ce)addition were *** as-cast microstructure of the steel,the size of carbide precipitation,carbide morphology,and mechanical properties were systematically studied through optical microscopy,scanning electron microscopy,and X-ray ***,through the Equilib module of the FactSage thermodynamics software,the changes in the precipitation type of the inclusions with Ce during the solidification of the steel were *** results indicate that the rare earth Ce is added into the steel to refine the as-cast microstructure of the *** types of inclusions in the steel are changed by the addition of *** precipitated carbide morphology changes from a complex rod shape to a relatively single lamellar *** rare earth inclusions formed in steel by a moderate addition of Ce can be severed as the core of heterogeneous nucleation of carbides,which reduce the size of carbide precipitation,promote the uniform distribution of carbide in the as-cast steel,and improve the mechanical properties of the as-cast high grade knives steel.

关键词： Carbide Microstructure Mechanical property Cerium High grade knives steel

Simulation of Flow Field of Oxygen Lance Gas Jet Utilized for 50 t Converter

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Journal of Iron and Steel Research International 2011年第4期18卷 11-18页

作者： LI jun-guo ZENG ya-nan WANG Jian-qiang han Zhi-jie College of Metallurgy and Energy Hebei Polytechnic University Tangshan 063009 Hebei China Tangshan Iron and Steel Co Ltd Tangshan 063016 Hebei China

Based on the operating conditions of oxygen lance utilized for a 50 t converter in Tangsteel,gas jet flow fields of three types of oxygen lances were simulated by FLUENT *** influence of lance configuration and lance level on penetrating area was studied through cold model *** results showed that the gas flow velocities of four-hole,variable angle four-hole and five-hole oxygen lances declined rapidly with an increase in gas jet length within 1 m,1 m and 0.8 m,***,the multi gas streams sprayed from these three lances should be syncretized at 1.6 m,1.7 m and 1.4 m,*** the highest lance level,the effective penetrating area of these three lances could be 0.255 m2,0.385 m2 and 0.0907 m2,*** was suggested that the effective penetrating area of variable angle four-hole oxygen lance was the biggest,while that of five-hole oxygen lance was the *** validity of numerical simulation results was proved through cold model *** lance level was suggested to be controlled in the range of 1-1.6 m,1-1.7 m and 0.8-1.4 m for the four-hole,variable angle four-hole and five-hole oxygen lances,respectively.

关键词： oxygen lance variable angle four-hole flow field