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PHOTODEGRADATION OF p-NITROCHLORBENZENE(p-NCB)USING NANOMETER-SIZED ZnO PARTICLES PREPARED BY REACTIVE EVAPORATION METHOD

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Acta Metallurgica Sinica(English Letters) 2004年第2期17卷 181-188页

作者： A.A.A.Saleh x.J.zhai Y.C.zhai Y.Fu M.M.Elomella School of Materials and Metallurgy,Northeastern University,Shenyang 11O006,China Sch. of Mat. and Metall. Northeastern Univ. Shenyang 110006 China

Photocatalytic degradations of p-nitrochlorbenzene (p-NCB) with distilled water wereinvestigated with ZnO crystals (catalyst) of 70nm in diameter under UV irradiation.The suitable experimental conditions are determined as: ZnO 0.25g, pH 7, p-NCBconcentration 30mg/L. These variables in terms of the degradation rate have beendiscussed, which was defined as the rate of the initial degradation to the final degrada-tion of p-NCB. When all of the experimental degradation rate values are plotted as afunction of irradiation time, all of the points appeared on a single line for wide range ofp-NCB degradations. On the basis of these results, it has been concluded that at lowerZnO catalyst amount, much of the light is transmitted through the slurry in the con-tainer beaker, while at higher catalyst amount, all the incident photons are observedby the slurry. Degradation rates of p-NCB were found to decrease with increasingsolution pH. It has been concluded that the maximum degradation rate values of p-NCB under principally the same experimental conditions mentioned above are 97.4%,98.8% and 95.5% at 100min respectively. The results suggest that the photocatalyticdegradation is initiated by an oxidation of the p-NCB through ZnO surface-adsorbedhydroxyl radicals. Absorption spectra are recorded using spectrophotometer before andafter UV-irradiation in the wavelength range 200-400nm at room temperature. Itis found that the variation of irradiation time over the range 20-100min resulted inchange in the form of the spectrum linear absorption and a higher maximum valuewill be obtained at longer irradiation time.

关键词： reactive evaporation method nano-ZnO particles pnitrochlorbenzene (p-NCB, ultraviolet light spectrophotometer catalyst

Carbon isotopes, sulfur isotopes, and trace elements of the dolomites from the Dengying Formation in Zhenba area, southern Shaanxi: Implications for shallow water redox conditions during the terminal Ediacaran

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Science China Earth Sciences 2015年第7期58卷 1107-1122页

作者： CHEN YaLi CHU xueLei ZHANG xingLiang zhai MingGuo State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth Science University of Chinese Academy of Sciences State Key Laboratory for the Continental Dynamics Northwest University

Carbon isotope, sulfur isotope, and trace element(including Rare Earth Elements, REE) analyses were conducted on the carbonates of the Dengying Formation at Lianghekou section in southern Shaanxi to reconstruct the terminal Ediacaran shallow-water environment on the northwestern margin of the Yangtze Platform. At Lianghekou section, samples in the middle 50-m of the Beiwan Member show characteristics of low ΣREE concentrations, no MREE-enriched REE distribution patterns, high Ce/Ce* values close to 1, and enriched redox-sensitive elements, whereas samples in the lower 30-m and upper 10-m show opposite characteristics of high ∑REE concentrations, MREE-enriched REE distribution patterns, low Ce/Ce* values around 0.6, and no redox-sensitive elements enriched, indicating that oxygenation did occur in the shallow water on the northwestern margin of the Yangtze Platform and redox conditions of the shallow water fluctuated from relatively oxygenated to anoxic and then back to oxygenated again. We propose that the anoxia appeared in middle of the Beiwan time may associate with the anoxic upwelled water. On one hand, abundant nutrients were brought in by this upwelling event, which stimulated the photosynthetic carbon fixation and increased the organic carbon burial under this anoxic condition, causing a peak of 3.6‰ in δ 13 C. On the other hand, because the anoxic upwelled water replaced the oxic shallow water, together with the increasing organic matter in the water column, bacterial sulfate reduction was enhanced and therefore quickly reduced the sulfate concentration, which eventually caused δ 34 S increasing to 50‰. However, as the upwelling gradually disappeared, δ 13 C and δ 34 SCAS values decreased as well in the late Beiwan time, indicating the shallow water went back to suboxic or oxic again.

关键词： Yangtze Platform southern Shaanxi Ediacaran trace elements carbon isotopes sulfur isotopes

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Detection and Attribution of Changes in Summer Compound Hot and Dry Events over Northeastern China with CMIP6 Models

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Journal of Meteorological Research 2022年第1期36卷 37-48页

作者： Wei LI Zhihong JIANG Laurent ZxLI Jing-Jia LUO Panmao zhai Key Laboratory of Meteorological Disaster of Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China Laboratory of Severe Weather Fujian Institute of Meteorological SciencesFuzhou 350001China Laboratoire de Météorologie Dynamique Centre National de la Recherche ScientifiqueSorbonne UniversitéEcole Normale SupérieureEcole PolytechniqueParis 75252France State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081China

Northeastern China has experienced a significant increase in summer compound hot and dry events(CHDEs),posing a threat to local agricultural production and sustainable *** study investigates the detectable anthropogenic signal in the long-term trend of CHDE and quantifies the contribution of different external forcings.A probability-based index(PI)is constructed through the joint probability distribution to measure the severity of CHDE,with lower values representing more severe *** of CHDE to external forcing was assessed with simulations from the Coupled Model Intercomparison Project phase 6(CMIP6).The results show a significant increase in the severity of CHDE over northeastern China during the past *** trend of regional averaged PI is-0.28(90%confidence interval:-0.43 to-0.13)per 54 yr and it is well reproduced in the historical forcing *** attribution method of optimal fingerprinting was firstly applied to a two-signal configuration with anthropogenic forcing and natural forcing;the anthropogenic impact was robustly detected and it explains most of the observed trend of ***,three-signal analysis further demonstrated that the anthropogenic greenhouse gases dominantly contribute to the observed change,while the anthropogenic aerosol and natural forcing have almost no contribution to the observed *** a compound event concurrently exceeding the 95 th percentile of surface air temperature and precipitation reversal in the current period,its likelihood exhibits little change at 1.5℃global warming,but almost doubled at 2.0℃global warming.

关键词： compound hot and dry event(CHDE) detection and attribution northeastern China future projection

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区域医疗系统抗震韧性综述

哈尔滨工业大学学报 2025年第1期57卷 1-12页

作者：裴顺顺翟长海胡杰结构工程灾变与控制教育部重点实验室(哈尔滨工业大学) 哈尔滨150090 土木工程智能防灾减灾工业和信息化部重点实验室(哈尔滨工业大学) 哈尔滨150090

韧性作为一种新的灾害风险管理理念,已成为防灾减灾领域的研究热点,考虑到医疗系统在城市运行和灾后救援中的重要作用,在地震期间和之后,区域医疗系统应该具有足够的韧性,并提供连续的医疗服务。如何综合考虑区域范围内多家医院和交通... 详细信息

韧性作为一种新的灾害风险管理理念,已成为防灾减灾领域的研究热点,考虑到医疗系统在城市运行和灾后救援中的重要作用,在地震期间和之后,区域医疗系统应该具有足够的韧性,并提供连续的医疗服务。如何综合考虑区域范围内多家医院和交通系统的安全性、应急响应能力、多系统的整合与协作,有效评估区域医疗系统的抗震韧性水平,并提出科学的改进建议,对建设韧性城乡具有重要的理论意义。本文通过梳理国内外文献,阐明了区域医疗系统韧性的概念和内涵,总结了地震后短期应急和长期修复两个阶段韧性评估的重点,归纳了现有区域医疗系统韧性的评估框架,从医院集群系统、面向医疗的交通系统、应急医疗服务系统和医疗-交通耦合系统4个方面阐述了现有评估方法。区域医疗系统韧性的研究旨在提高其面对灾害时的抵抗性、短期适应性和长期恢复性,这些研究对于满足紧急和日常的医疗需求以及指导灾后恢复具有重要意义。目前区域医疗系统抗震韧性的研究取得了一些进展,但仍然存在一些挑战,本文最后展望了未来的研究方向。

关键词：区域医疗系统单体医院交通系统抗震韧性功能评估恢复时间

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张国龙成长小说中的引路人解析

四川文理学院学报 2025年第1期35卷 35-42页

作者：翟淼淼淄博师范高等专科学校人文学院山东淄博255130

川籍儿童文学作家张国龙对青少年成长倾注了满腔热情,创作了一系列成长小说,塑造了众多具有独立自主意识、积极进取精神以及坚韧生命力的青少年形象。在这些作品中,伴随主人公成长的引路人形象引人注目。这些引路人形象包括导师型和伙... 详细信息

川籍儿童文学作家张国龙对青少年成长倾注了满腔热情,创作了一系列成长小说,塑造了众多具有独立自主意识、积极进取精神以及坚韧生命力的青少年形象。在这些作品中,伴随主人公成长的引路人形象引人注目。这些引路人形象包括导师型和伙伴型的正面导向引路人、反面导向引路人、“中间地带”引路人以及自然神灵的引导者。他们以各自独特的方式影响着主人公的成长轨迹,同时也强化了文本的叙事功能。

关键词：张国龙成长小说引路人

Cutting Characteristics of Zr-Based Bulk Metallic Glass

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Journal of Materials Science & Technology 2015年第2期31卷 153-158页

作者： D.x.Han G.Wang J.Li K.C.Chan S.To F.F.Wu Y.L.Gao Q.J.zhai Laboratory for Microstructures Shanghai University Department of Industrial and System Engineering The Hong Kong Polytechnic University

Cutting behavior exerts a considerable influence on the fabrication of bulk metallic glass(BMG) components. In this study,the influences of machining parameters(i.e.,depth of cutting,feed rate,and spindle rate) on the turned surface of a Zr-based BMG after observing the 3D morphologies of this surface were *** results showed that the influence of the spindle rate on the surface morphologies is more substantial as compared to the depth of cutting and the feed rate. Nanoscratch tests were conducted to further characterize the separation mechanism of the chips,which revealed that the chips are torn off the surface of a BMG because of inhomogeneous localized maximum shear stress.

关键词： Bulk metallic glass Ultra-precision machining Surf

行为暴露视角下高温健康风险评估——以南京市为例

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灾害学 2025年第1期40卷 53-60页

作者：张钰佳翟国方何仲禹南京大学建筑与城市规划学院江苏南京210093

气候变化背景下极端高温天气对人群健康带来极大挑战。高温健康风险的地理分布不均,因此,进行空间异质性评估对于识别高风险区域和指导空间规划至关重要。该文以步行指数来评估人们在户外活动中遭受高温的可能性,并构建高温健康风险评... 详细信息

气候变化背景下极端高温天气对人群健康带来极大挑战。高温健康风险的地理分布不均,因此,进行空间异质性评估对于识别高风险区域和指导空间规划至关重要。该文以步行指数来评估人们在户外活动中遭受高温的可能性,并构建高温健康风险评估体系。以南京市主城区为研究对象,从精细化尺度定量评估高温健康风险的空间分布,精准识别高风险区域及主导风险因子。结果表明:①南京主城区步行指数整体呈“内高外低、多核心”的空间格局,高步行指数区具有较高的高温健康风险。②高温危险性、暴露性、敏感性和适应能力在空间分布上存在明显的异质性。高危险性区域集中于高密度建成区和工业用地,城市中心区域呈“高暴露、高敏感、高适应”特征、外围区域则相反。③高风险区域的主导因子类型在空间上呈圈层性:中心区域以高暴露性为主、过渡区域风险因素为综合,外围区域以低适应能力为主。该研究依据主导风险因子提出韧性提升路径,以期为降低城市高温健康风险提供参考。

关键词：高温健康风险风险评估韧性行为暴露步行指数南京市

FDNet: Fourier transform guided dual-channel underwater image enhancement diffusion network

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Science China Technological Sciences 2025年第1期 62-78页

作者： Zhen ZHU xiaobo LI Qianwen MA Jingsheng zhai Haofeng HU School of Marine Science and Technology Tianjin University College of Mechanical Engineering and Automation Fuzhou University

Due to the scattering and absorption of light, underwater imaging yields suboptimal results characterized by low brightness, diminished image contrast, and the loss of details. Current learning-based underwater image enhancement(UIE)methods mainly focus on addressing these issues in the spatial domain, with limited attention to the Fourier frequency *** propose the Fourier transform guided dual-channel underwater image enhancement diffusion network(FDNet), aiming to fully leverage frequency domain information and the characteristics of a diffusion-based generation model. The amplitude-phase dualchannel not only effectively provides feedback on the energy distribution of the image but also incorporates crucial image structure and texture information. Capitalizing on these advantages, we first introduce a Fourier transform-based amplitude-phase dualchannel enhancement front-end network for UIE. This network significantly improves the quality of the network's image input,including brightness and contrast, by incorporating phase congruency edge enhancement and prior-driven amplitude mapping strategies. The preceding network mitigates the overall training challenges caused by poor input image quality. Simultaneously,the application of denoising networks based on lightweight transformers effectively improves the computational time required for each iteration during model training. The results indicate that FDNet outperforms many current learning-based UIE algorithms in restoring images across multiple real underwater image datasets, demonstrating more robust generalization capabilities in degraded underwater scenarios. The competitive performance advantage achieved in enhancing visual quality underscores the effectiveness of our method.

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依法依规加强医疗机构人体器官捐献与移植工作体系和人体器官移植伦理委员会建设

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