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Enhancing low-temperature NO_x storage and reduction performance of a Pt-based lean NO_x trap catalyst

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Rare Metals 2019年第1期38卷 81-86页

作者： Tong Wang li-Wei jia Xiu-Ting Wang Gang Wang Fu-Qiang Luo jia-Ming Wang School of Automotive and Traffic Engineering Jiangsu University Wuxi Weifu Environmental Catalysts Co. Ltd

Two lean NO_x trap(LNT) catalysts, Pt/BaO/CeO_2 + Al_2O_3 and Pt/BaO/CeO_2-Al_2O_3, were prepared and compared for low-temperature(< 250℃) NO_x storage and reduction performance. The influence of the form of ceria on... 详细信息

Two lean NO_x trap(LNT) catalysts, Pt/BaO/CeO_2 + Al_2O_3 and Pt/BaO/CeO_2-Al_2O_3, were prepared and compared for low-temperature(ling, product selectivity and thermal *** coupled plasma-atomic emission spectrometry(ICP-AES), Brunner-Emmet-T eller(BET), H_2-pulse chemisorption and X-ray diffraction(XRD) were conducted to characterize the physical properties of LNT catalysts. NO_x storage capacity and NO_x conversion efficiency were measured to evaluate NO_x storage and reduction performance of LNT catalysts. Pt/BaO/CeO_2-Al_2O_3 catalyst exhibits higher NO_x storage capacity than Pt/BaO/CeO_2 + Al_2O_3 catalyst in the temperature range of 150-250 ℃. Meanwhile, Pt/BaO/CeO_2-Al_2O_3 catalyst shows better NO_x conversion efficiency and N_2 selectivity. XRD results indicate that the thermal stability of CeO_2-Al_2O_3 complex oxide is superior to that of pure CeO_2. H_2-pulse chemisorption results show that Pt/BaO/CeO_2-Al_2O_3 catalyst has higher Pt dispersion than Pt/BaO/CeO_2 + Al_2O_3 catalyst over fresh and aged samples. The improved physical properties of Pt/BaO/CeO_2-Al_2O_3 catalyst are attributed to enhance the NOx storage and reduction performance over Pt/BaO/CeO_2 + Al_2O_3 catalyst.

关键词： NOx storage and reduction Low temperature Ceria Ceria-alumina LNT

Design of Mooring System for Oil Storage Vessels

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China Ocean Engineering 2003年第4期18卷 541-550页

作者： li Wen-long(李文龙) TAN jia-hua(谭家华) School of Naval Architecture and Ocean Engineering Shanghai Jiao Tong University Shanghai200030 China School of Naval Architecture and Ocean EngineeringShanghai Jiao Tong University Shanghai200030 China

The floating oil storage system has been proposed as a new facility for Strategic Petroleum Reserve (SPR) in China. Mooring is one of the key technologies to ensure the safety, reliability, and performance of the oil storage system. This paper describes the concept, analysis, design and reliability of the mooring system. For mooring system design of these oil vessels, analysis is essential of the behavior of the vessel in connection with mooring facilities of nonlinear resilience. A nonlinear mathematical model for analyzing a moored vessel is established and solved. Some results of numerical simulations are presented. Assessment of the safety regarding the mooring system in terms of failure probability is carried out. Another simulation model for calculating the failure probability of the mooring system is proposed. The design parameters that have an influence on the characteristics of the failure probability have been identified. The simulation results,show that the mooring system has an annual reliability value of 0.999998. The proposed simulation method is proved to be effective in quantitative evaluation of the safety of the mooring system for floating oil storage vessels.

关键词： petroleum reserve oil storage vessels mooring system design nonlinear numerical simulation safety assessment

马铃薯Y病毒CI蛋白密码子优化、真核表达体系建立及单克隆抗体制备

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植物病理学报 2024年第3期54卷 544-554页

作者：尹国英贾蒙骜常永春张盼李震蔡长春贵州省烟草科学研究院贵阳550081 山西农业大学农学院晋中030800 贵州省烟草公司黔西南州公司兴义562400 湖北省烟草科学研究院武汉430030

编码马铃薯Y病毒(potato virus Y,PVY)CI蛋白的核酸序列具有多个类似原核生物启动子元件的区域,有可能在原核细胞中翻译出对原核细胞具有毒性的蛋白,因此该序列难以按照常规的试验方法进行载体构建。在不改变CI氨基酸序列的基础上,对编... 详细信息

编码马铃薯Y病毒(potato virus Y,PVY)CI蛋白的核酸序列具有多个类似原核生物启动子元件的区域,有可能在原核细胞中翻译出对原核细胞具有毒性的蛋白,因此该序列难以按照常规的试验方法进行载体构建。在不改变CI氨基酸序列的基础上,对编码CI的核酸序列进行改造,成功构建了含有CI开放阅读框(ORF)的表达载体,利用真核无细胞蛋白表达系统成功实现了CI蛋白的表达。通过亲和层析纯化,将CI蛋白免疫Balb/c小鼠,共制备了6株单克隆抗体。间接EliSA和Western blot免疫印迹证明,其中4B7_2D6(IgG1)单克隆抗体,灵敏度最高,特异性最强。CI蛋白的成功表达及单克隆抗体的获得,为后续研究CI蛋白的结构与功能提供了前提条件,对进一步探索CI与植物蛋白互作机理以及PVY的检测技术具有重要意义。

关键词： CI蛋白密码子偏好性真核表达单克隆抗体

Physical Properties of Al-doped ZnO and Ga-doped ZnO Thin Films Prepared by Direct Current Sputtering at Room Temperature

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Journal of Wuhan University of Technology(Materials Science) 2017年第1期32卷 85-88页

作者：朱科 YANG Ye li jia SONG Weijie Department of Physics and Mathematics Hunan Institute of Technology Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences

Al-doped zinc oxide（AZO） and Ga-doped zinc oxide（GZO） thin films with the same doping concentration（3.6 at%） were deposited on glass substrates at room temperature by direct current（DC） magnetron ***,we comparatively studied the doped thin films on the basis of their structural,morphological,electrical,and optical properties for optoelectronic *** thin films exhibited excellent optical properties with more than 85%transmission in the visible *** GZO thin film had better crystallinity and smoother surface morphology than the AZO thin *** conductivity of the GZO thin film was improved compared to that of the AZO thin film：the resistivity decreased from 1.01×10^-3 to 3.5×10^-4 Ω cm,which was mostly due to the increase of the carrier concentration from 6.5×10^20 to 1.46×10^21cm^-*** results revealed that the GZO thin film had higher quality than the AZO thin film with the same doping concentration for optoelectronic applications.

关键词： room temperature ZnO thin films sputtering electrical properties

Random walk search in unstructured P2P

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Journal of Systems Engineering and Electronics 2006年第3期17卷 648-653页

作者： jia Zhaoqing You Jinyuan Rao Ruonan li Minglu Dept. of Computer Science and Engineering Shanghai Jiaotong Univ. Shanghai 200030 P. R. China Dept. of Foundation Science the First Aeronautical Inst. of the Air Force Xinyang 464000 P. R. China

Unstructured P2P has power-law link distribution, and the random walk in power-law networks is analyzed. The analysis results show that the probability that a random walker walks through the high degree nodes is high in the power-law network, and the information on the high degree nodes can be easily found through random walk. Random walk spread and random walk search method （RWSS） is proposed based on the analysis result. Simulation results show that RWSS achieves high success rates at low cost and is robust to high degree node failure.

关键词： unstructured P2P search random walk search random walk spread power-law network.

Improved hemimorphite flotation using xanthate as a collector with S(Ⅱ) and Pb(Ⅱ) activation

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International Journal of Minerals,Metallurgy and Materials 2018年第8期25卷 849-860页

作者： Kai jia Qi-ming Feng Guo-fan Zhang Qing Shi Yuan-jia Luo Chang-bin li School of Mineral Processing and Bioengineering Central South UniversityChangsha 410083China

The flotation of hemimorphite using the S(Ⅱ)–Pb(Ⅱ)–xanthate process,which includes sulfidization with sodium sulfide,activation by lead cations,and subsequent flotation with xanthate,was *** flotation results indicated that hemimorphite floats when the S(Ⅱ)–Pb(Ⅱ)–xanthate process is used; a maximum recovery of approximately 90% was ***-potential,contact-angle,scanning electron microscopy–energy-dispersive spectrometry(SEM–EDS),and diffuse-reflectance infrared Fourier transform spectroscopy(DRIFTS) measurements were used to characterize the activation products on the hemimorphite surface and their subsequent interaction with sodium butyl xanthate(SBX).The results showed that a Zn S coating formed on the hemimorphite surface after the sample was conditioned in an Na2 S ***,the formation of a Zn S coating on the hemimorphite surface did not improve hemimorphite *** the subsequent addition of lead cations,Pb S species formed on the mineral *** formation of the Pb S species on the surface of hemimorphite significantly increased the adsorption capacity of SBX,forming lead xanthate(referred to as chemical adsorption) and leading to a substantial improvement in hemimorphite *** results indicate that the addition of lead cations is a critical step in the successful flotation of hemimorphite using the sulfidization–lead ion activation–xanthate process.

关键词： hemimorphite sulfidization lead ion activation xanthate zeta potential DRIFTS

Visual landmark-directed scatter-hoarding of Siberian chipmunks Tamias sibiricus

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Integrative Zoology 2016年第3期11卷 175-181页

作者： Dongyuan ZHANG jia li Zhenyu WANG Xianfeng YI College of life Sciences Jiangxi Normal UniversityNanchangChina

Spatial memory of cached food items plays an important role in cache recovery by scatter-hoarding ***,whether scatter-hoarding animals intentionally select cache sites with respect to visual landmarks in the environment and then rely on them to recover their cached seeds for later use has not been extensively ***,there is a lack of evidence on whether there are sex differences in visual landmark-based food-hoarding behaviors in small rodents even though male and female animals exhibit different spatial *** the present study,we used a scatter-hoarding animal,the Siberian chipmunk,Tamias sibiricus to explore these questions in semi-natural *** results showed that *** preferred to establish caches in the shallow pits labeled with visual landmarks(branches of Pinus sylvestris,leaves of Athyrium brevifrons and PVC tubes).In addition,visual landmarks of *** facilitated cache recovery by *** also found significant sex differences in visual landmark-based food-hoarding strategies in Siberian ***,rather than females,chipmunks tended to establish their caches with respect to the visual *** studies show that *** rely on visual landmarks to establish and recover their caches,and that sex differences exist in visual landmark-based food hoarding in Siberian chipmunks.

关键词： cache site food-hoarding animals sex difference visual landmark

Experimental investigation on debris flow resistance and entrainment characteristics:effects of the erodible bed with discontinuous grading

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Journal of Mountain Science 2022年第8期19卷 2397-2419页

作者： li Pu WANG jia-ding HU Kai-heng QIU Hai-jun XIE jia-lin State Key Laboratory of Continental Dynamics/Department of Geology Northwest UniversityXi'an 710069China Key Laboratory of Mountain Hazards and Earth Surface Processes Chinese Academy of SciencesChengdu 610041China Institute of Mountain Hazards and Environment Chinese Academy of Sciences&Ministry of Water ConservancyChengdu 610041China College of Urban and Environmental Sciences Northwest UniversityXi'an 710127China

Debris flow deposits in natural channels typically have a wide grain size distribution(GSD).The effects of bed sediment GSD on the basal entrainment rate are neglected in current debris flow erosion *** investigations have detected three different vertical graded bedding structures:normal,inverse,and mixed-gradation,characterized by discontinuous gradation sediment and almost without intermediate-sized *** study conducted small-scale flume experiments to investigate the debris flow resistance forces and entrainment characteristics by incorporating the effects of discontinuous grading bed *** graded bed sediments with varying fine particle content,volumetric water content(VWC),and roundness were designed for *** flow resistance in erodible beds generally increased in the group with gravel of larger-sized coarse particle,lower roundness,and higher bed sediment *** discontinuous grading bed sediment,the entrained depths increased in the group with gravel of smaller coarse particle sizes,larger amounts of fine particles,and higher sediment roundness,and decreased with larger *** abnormality may be attributed to the disproportionately large effects of viscous flow resistance in our small-scale flume *** maximum erosion rates of the continuous bed sediment were higher than those of the corresponding discontinuous bed sediment with the same maximum coarse gravel *** is because,for discontinuous grading bed sediments,localized failure of intermediate-sized sediment grains may cause a large-scale collapse of the solid grain skeleton and enhance basal entrainment rates.A revised formula for calculating the debris flow entrainment rate is proposed by incorporating the kurtosis coefficient,which describes the distribution of discontinuous bed sediments and fine particle *** revised formula could facilitate an elaborate estimation of basin erosion and sediment runoff and reveal the development an

关键词： Debris flow Resistance force Entrainment characteristic Discontinuous gradation Roundness Entrainment model

临床护士额外任务负荷量表的编制及信效度检验

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中华现代护理杂志 2024年第20期30卷 2731-2736页

作者：杨卫红李雪刘晶赵佳张全英贾冠华新乡医学院第一附属医院护理部新乡453100 新乡医学院第一附属医院肿瘤内科二病区新乡453100 新乡医学院第一附属医院门诊部新乡453100

目的:编制临床护士额外任务负荷量表并检验其信效度。方法:基于工作需求-控制模型,在文献检索与质性访谈的基础上,通过德尔菲专家函询、预调查形成初量表。于2023年9月选取新乡医学院第一附属医院和新乡市中心医院的813名临床护士调查,... 详细信息

目的:编制临床护士额外任务负荷量表并检验其信效度。方法:基于工作需求-控制模型,在文献检索与质性访谈的基础上,通过德尔菲专家函询、预调查形成初量表。于2023年9月选取新乡医学院第一附属医院和新乡市中心医院的813名临床护士调查,用于进行信效度检验。2023年10月选取新乡医学院第一附属医院和新乡市中心医院的1 050名临床护士进行调查,并检验量表的信效度水平。结果:最终形成的临床护士额外任务负荷量表包括2个维度,共12个条目。条目水平的内容效度指数为0.86~1.00,量表水平的内容效度指数为0.84;探索式因子分析共提取出2个公因子,累计方差贡献率为74.55%。验证性因子分析结果显示,χ ^(2)/ df为1.613, GFI为0.928, CFI为0.971, NFI为0.928, IFI为0.971, RMSEA为0.024;工作环境需求维度Cronbach's α系数为0.897,个体行为限制Cronbach's α系数为0.955,总量表Cronbach's α系数为0.950,分半信度为0.850。结论:本研究所编制的临床护士额外任务负荷量表具有良好的信效度水平,可用于评估和量化临床护士额外任务负荷的程度。

关键词：护士额外任务负荷量表编制心理健康护理