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洗衣废水影响纳米银团聚及溶解行为的关键因素研究进展

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日用化学工业（中英文） 2024年第7期54卷 844-852页

作者：谷秀君罗萍蔡承建杨德军蒋家超杨靖中国矿业大学环境与测绘学院江苏徐州221116 中国矿业大学江苏省资源与环境信息工程重点实验室江苏徐州221116 江苏省徐州环境监测中心江苏徐州221000

纳米银因卓越的抗菌性能被广泛用于纺织品生产中。然而,在纺织品洗涤过程中,大量的纳米银会释放并进入到洗衣废水中。不同的洗涤条件决定了释放出的纳米银的团聚及溶解行为,进而影响后续环境过程并对水生生物及生态系统产生负面影响。... 详细信息

纳米银因卓越的抗菌性能被广泛用于纺织品生产中。然而,在纺织品洗涤过程中,大量的纳米银会释放并进入到洗衣废水中。不同的洗涤条件决定了释放出的纳米银的团聚及溶解行为,进而影响后续环境过程并对水生生物及生态系统产生负面影响。为探究不同洗涤条件对纳米银团聚及溶解行为的具体影响,降低纳米银所带来的环境风险,文章归纳了国内外相关研究文献,在分析洗衣废水特点的基础上,讨论了废水中洗涤剂种类、光照、pH值、离子强度等条件对纳米银团聚及溶解行为的单独或联合作用与影响机理,并根据机理提出了减小纳米银生物毒性的建议,包括减少洗涤过程中纳米银的释放及洗衣废水处理方法的改善,最后对洗衣废水中纳米银未来的研究方向进行展望,提出了后续研究建议。

关键词：洗衣废水纳米银团聚溶解机理

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西双版纳州柚子园土壤养分状况研究

西部林业科学 2024年第2期53卷 152-159页

作者：张传光姜存良贠新华沈艳杨德军云南省林业和草原科学院云南昆明650201 云南省林业和草原科学院热带林业研究所云南西双版纳666102 云南省森林植物培育与开发利用重点实验室/国家林业局云南珍稀濒特森林植物保护和繁育重点实验室云南昆明650201 云南滇中高原森林生态系统国家定位观测研究站云南昆明650201

为了解西双版纳州主要柚子园土壤养分状况,以西双版纳州10个主要柚子种植园共42个土壤样本为研究材料,通过测定其土样基本理化性质和养分含量,并采用内梅罗综合指数法对土壤进行肥力评价。结果显示:(1)西双版纳州柚子园土壤养分肥力均... 详细信息

为了解西双版纳州主要柚子园土壤养分状况,以西双版纳州10个主要柚子种植园共42个土壤样本为研究材料,通过测定其土样基本理化性质和养分含量,并采用内梅罗综合指数法对土壤进行肥力评价。结果显示:(1)西双版纳州柚子园土壤养分肥力均为中等肥沃,虽可以基本满足柚子生长需求,但高品质柚子园占比不足20%,70%柚子园土壤酸碱度pH偏低,不适合生产高品质柚子,1号和7号柚子园土壤pH处于最适的生长区间。(2)大量元素除水解性氮(HN)和全钾(TK)外均属于适量水平,35.42%土壤样品全磷(TP)达到极丰富水平,高品质柚子与土壤适当的氮(N)或有机质(SOM)含量,以及较高的磷(P)、钾(K)含量密切相关。(3)有效硫(AS)处于缺乏水平,交换性钙(ECa)和镁(EMg)处于极丰富和丰富水平,但不是造成西双版纳州柚子品质差异的主要因子。有效锰(AMn)、有效锌(AZn)、有效硼(AB)在果品最好的1号柚子园中含量丰富,且显著高于其他果园。研究结果表明:土壤质量可以显著地影响柚子品质,通过提升土壤pH,控制氮肥用量,增施磷、钾、锰、锌、硼,有望提高西双版纳柚子品质。

关键词：柚子土壤养分肥力评价西双版纳

高分辨MRI在评估下段直肠癌术前TN分期及环周切缘中的敏感性分析

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科技与健康 2024年第15期3卷 5-8页

作者：林晓强杨德军周慧术柳州市中医医院放射科广西柳州545001

探讨高分辨MRI在评估下段直肠癌术前TN分期及环周切缘中的敏感性。选择65例下段直肠癌患者,对其实施盆腔高分辨MRI平扫,记录瘤体下缘与肛门外缘的距离、瘤体矢状位与斜轴位直径,完善MRI-TN分期,评估直肠系膜筋膜(MRF)及环周切缘受累状况... 详细信息

探讨高分辨MRI在评估下段直肠癌术前TN分期及环周切缘中的敏感性。选择65例下段直肠癌患者,对其实施盆腔高分辨MRI平扫,记录瘤体下缘与肛门外缘的距离、瘤体矢状位与斜轴位直径,完善MRI-TN分期,评估直肠系膜筋膜(MRF)及环周切缘受累状况,与术后病理结果进行对比。结果显示,65例下段直肠癌患者,MRI-T分期正确率为84.6%,与病理T分期的一致性好(Kappa值为0.757)。MRI-N分期正确率为67.7%,与病理N分期的一致性一般(Kappa值为0.514)。MRI对MRF受累与否的诊断准确率为90.8%(59/65),MRI-MRF与术后病理的一致性较好(Kappa值为0.789)。MRI检查明确环周切缘肿瘤浸润与否的准确率是92.3%(60/65),MRI-MRF与术后病理的一致性较好(Kappa值为0.662)。研究发现,高分辨MRI检查能准确进行直肠癌术前TN分期,可判断环周切缘的肿瘤发生率,有助于临床合理选择治疗方案。

关键词：磁共振成像下段直肠癌 TN分期环周切缘

Influence of Ar/N_2 Flow Rate on Structure and Property for TaN/NbN Multilayered Coatings

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Journal of Materials Science & Technology 2007年第4期23卷 461-464页

作者： Xuehua ZHANG Yuanbin KANG Sipeng LIU Qiang LI Ying yang Xiangyun DENG dejun LI College of Physics and Electronic Information Science Tianjin Normal University Tianjin 300074 China

TaN/NbN multilayered coatings with nanoscale bilayer periods were synthesized at different Ar/N2 flow rates by RF （radio frequency） magnetron sputtering. XRD （X-ray diffraction） and Nano Indenter System were employed to investigate the influence of Ar/N2 flow rate （FAr：FN2） on microstructure and mechanical properties of the coatings. The low-angle XRD pattern indicated a well-defined composition modulation and layer structure of the multilayered coating. All multilayered coatings almost revealed higher hardness than the rule-of-mixtures value of monolithic TaN and NbN coatings. At FAr：FN2=10, the multilayered coating possessed desirable hardness, elastic modulus, internal stress, and fracture resistance, compared with ones synthesized at other Ar/N2 flow rates. The layered structure with strong mixture of TaN （110）, （111）, （200） and Nb2N （101）textures should be related to the enhanced mechanical properties.

关键词： RF magnetron sputtering TaN/NbN multilayered coatings Nanoscale mechnical properties

Electrochemical Study of Hypophosphite

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International Journal of Minerals,Metallurgy and Materials 1998年第1期12卷 23-25页

作者： Yuguo yang Dongbai Sun Dongbai Sun dejun yang (Materials Science and Engineering School, University of Science and Technology Beijing, Beijing 100083, China) Materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China

Electrochemical behavior of hypophosphite was studied with cyclic voltammogram in acidic solution(pH = 4.6) at 80℃. Two anodic peaks were observed on gold electrode at - 0.44V and - 0.59 V (SCE),respectively, and no corresponding cathodic peaks were obtained. The one at - 0.44 V wits ascribed to the oxidation oftautomeric form of hypophosphite, the other at - 0.59 V was due to the oxidation of absorbed form of hypophosphite. The two oxidation reactions were believed to be the electron source of nickel ion reduction in electrolessnickel processes.

关键词： cyclic voltammogram electroless nickel plating gold electrode hypophosphite

Preventing Dropping Packets Attack in Sensor Networks:A Game Theory Approach

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Wuhan University Journal of Natural Sciences 2008年第5期13卷 631-635页

作者： yang Libin MU dejun CAI Xiaoyan College of Automation Northwestern Polytechnical UniversityXi＇an 710072 Shaanxi China

Focusing on dropping packets attacks in sensor networks, we propose a model of dropping packets attack-resistance as a repeated game based on such an assumption that sensor nodes are rational. The model prevents malicious nodes from attacking by establishing punishment mechanism, and impels sensor networks to reach a collaborative Nash equilibrium. Simulation results show that the devised model can effectively resist the dropping packets attacks（DPA） by choosing reasonable configuration parameters.

关键词： wireless sensor network repeated game Nash equilibrium attack-resistant mechanism

Effects of complexing agents on acidic electroless nickel deposition

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Rare Metals 2010年第4期29卷 401-406页

作者： JIN Ying YU Hongying yang dejun SUN Dongbai National Center for Materials Service Safety University of Science and Technology Beijing Beijing 100083 China Corrosion andProteetion Center School of Materials Science andEngineering University of Science and Technology Beijing Beij'ing 100083 China

Our previous study reported the influences of different complexing agents on electroless nickel （EN） by examining the properties of the deposits. In the present work, the effects of four common-used complexing agents on EN deposition rate and the stability of solution pH values were examined, either with an acetic pH buffer agent or absent of them. It is indicated that the pH buffeting effect of them is dominative when the EN solution is lack of the pH buffer. Under this situation, the EN deposition rate increases with the concentration of complexing agents increasing. The EN deposition rate decreases with fin＇ther adding the complexing agent when the solution already has enough pH buffer capability. Electrochemical impedance spectroscopy obtained during EN deposition illustrates that, in this case, the enhanced reaction resistance is the main reason for a lower deposition rate. However, the influence of polarization caused by mass transfer is not negligible at high complex ratio for sodium citrate and malic acid EN solutions.

关键词： electroless nickel complexing agents electrochemical impedance spectrum reaction resistance pH value

A PASSIVATION STUDY OF Ti-MODIFIED Fe—BASE ALLOY SYNTHESIZED BY MAGNETRON SPUTTERING TECHNIQUE

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Acta Metallurgica Sinica(English Letters) 1994年第1期7卷 27-30页

作者： LI Huiqin, ZHOU Honghui, yang dejun, SUN DongbaiUniversity of Science and Technology Beijing, China

A set of fracture device was designed on the basis of traditional scratching-electrode technology and used to study the passivation process of two magnetron-sputtered stainless sleel coatings (amorphous and crystalline struture). The results of fracture tests in 3.5 % NaCl aqueous solution show that the amorphous alloy has a high bare surface reactivity and a high passive rate in comparison with the crystalline alloy. The effect of structure on corrosion resistance is also discussed. The excellent corrosion resistance of amorphous alloy is considered to be partly attributed to its great passivation ability.

关键词： passivation kinetics amorphous Fe-base alloy coating,corrosion resistance

Development of a deviation package method for low-cost robust optimization in compressor blade design

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Chinese Journal of Aeronautics 2024年第4期37卷 166-180页

作者： Mingzhi LI Xianjun YU dejun MENG Guangfeng AN Baojie LIU Research Institute of Aero-Engine Beihang UniversityBeijing 100191China National Key Laboratory of Science&Technology on Aero-Engine Aero-Thermodynamics Beihang UniversityBeijing 100191China AECC Shenyang Engine Research Institute Shenyang 110015China

Manufacture variations can greatly increase the performance variability of compressor blades. Current robust design optimization methods have a critical role in reducing the adverse impact of the variations, but can be affected by errors if the assumptions of the deviation models and distribution parameters are inaccurate. A new approach for robust design optimization without the employment of the deviation models is proposed. The deviation package method and the interval estimation method are exploited in this new approach. Simultaneously, a stratified strategy is used to reduce the computational cost and assure the optimization accuracy. The test case employed for this study is a typical transonic compressor blade profile, which resembles most of the manufacture features of modern compressor blades. A set of 96 newly manufactured blades was measured using a coordinate measurement machine to obtain the manufacture variations and produce a deviation package. The optimization results show that the scatter of the aerodynamic performance for the optimal robust design is 20% less than the baseline value. By comparing the optimization results obtained from the deviation package method with those obtained from widely-used methods employing the deviation model, the efficiency and accuracy of the deviation package method are demonstrated. Finally, the physical mechanisms that control the robustness of different designs were further investigated, and some statistical laws of robust design were extracted.

关键词： Manufacture variations Robust design optimization Compressor leading edge Aerodynamics Physical mechanism