基于NLP的工程伦理教育研究文献挖掘与分析

工程伦理教育是高等工程教育改革的重要一环。在"新工科"建设背景下，学界又掀起了工程伦理教育研究的热潮。基于自然语言处理技术（NLP），借助计量可视化工具，针对中国知网（CNKI）收录的212篇研究性文献，从文献关键词时间分布图、词频表、词云图、LDA主题聚类表等角度出发，开展机器学习环境下的工程伦理教育研究文献挖掘与分析，分析中国工程伦理教育的研究现状、理论基础和研究热点，指出目前工程伦理教育存在的问题，并从高校角度提出一些改进建议，为促进工程伦理教育提供了有效参考。     

Cadmium accumulation in Scenedesmus vacuolatus under freshwater conditions

Cd accumulation in cultures of Scenedesmus vacuolatus, a freshwater alga, was investigated in water samples from freshwater systems (two hard- and one softwater system) and compared to accumulation from synthetic culture medium. The Cd accumulation in S. vacuolatus was compared to total, labile, and free Cd measured by various analytical methods. In the hardwater samples, Cd accumulation was similar to accumulation from the culture medium and approximately followed the free ion activity model. In the softwater system, Cd accumulation increased with increasing free and total Cd concentrations, but was lower than expected from the free Cd2+ concentrations compared to the other freshwaters and culture media. Cd accumulation in the various freshwaters was not simply related to labile and free Cd concentrations measured by several methods. From experiments using fulvic acid as a ligand in the culture medium, no influence on Cd accumulation other than by modifying the Cd speciation was detected. Modeling of the Cd uptake revealed that besides cation and proton competition, other factors such as dissolved organic carbon composition and the presence of colloids might reduce Cd accumulation in softwater systems.     

轿车面漆抛光痕消除方法探讨

介绍了轿车面漆涂装生产过程中因抛光而产生抛光痕的原因和消除方法的探讨。     

Nanostructured gold films exhibiting almost complete absorption of light at visible wavelengths

Nanostructured metal surfaces have been known to exhibit properties that deviate from that of the bulk material. By simply modifying the texture of a metal surface, various unique optical properties can be observed. In this paper, we present a simple two step electrochemical process combining electrodeposition and anodization to generate black gold surfaces. This process is simple, versatile and up-scalable for the production of large surfaces. The black gold films have remarkable optical behavior as they absorb more than 93% of incident light over the entire visible spectrum and also exhibit no specular reflectance. A careful analysis by scanning electron microscopy reveals that these unique optical properties are due to their randomly rough surface, as they consist in a forest of dendritic microstructures with a nanoscale roughness. This new type of black films can be fabricated to a large variety of substrates, turning them to super absorbers with potential applications in photovoltaic solar cells or highly sensitive detectors and so on.

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鼓泡床内双组分颗粒流动行为的数值模拟

为了模拟预测粒径和密度同时存在差异的双组分颗粒体系的分级混合行为,基于欧拉-欧拉方法建立多流体模型,采用颗粒动力学理论描述颗粒相性质,分别通过Gidaspow和Syamlal曳力模型描述气-固相曳力和固-固相作用力。结果表明,模拟得到的轴向和径向颗粒浓度分布与实验数据吻合较好;当在较小气流速度下出现分级行为时,床层底部富沉积组分层中沉积组分的运动十分有限,而在较大气流速度下处于完全混合状态时,床层内部颗粒运动较为剧烈。     

大型建设企业集团工程项目集成控制系统研究

大型建设企业集团承建的工程项目多而复杂,跨地域、施工地点分散,参建单位多,协调难度大,工程项目集成控制系统越来越受到青睐.首先对大型建设企业集团工程项目集成控制系统的概念进行了深入的研究;从系统数据规划和系统结构设计两方面分析了大型建设企业集团工程项目集成控制系统的构建;并以中交第二航务工程局有限公司集成控制系统的开发和应用为案例,论证了工程项目集成控制系统是大型建设企业集团实现多项目、异地、分布式、协同决策、协同计划、协同执行和控制的有效方式之一,值得在建筑行业中进行推广.     

公共项目运行管理的模式选择

公共项目建设管理模式(如代建制)的研究已成为学术界的热点,然而运行管理模式尽管同样重要,却未得到足够的关注.本文在对力求准确把握公共项目运行管理原则和相关政策法规精神的基础上,将各种公共项目运行的具体做法归纳为六种模式,并分别解析了其原理、优点和不足;随后对公共用房、城市基础设施等几种主要类型的公共项目分别适宜采用的运行管理模式进行了阐述,以供政策制定者、设施运行管理者参考.     

沧州体育馆结构设计

沧州体育馆是一座可容纳6000人的综合性体育建筑,已于2010年竣工,将作为2014年召开的河北省第十四届体育运动会的主会场。本工程跨度大、造型新颖,结构设计具有一定的挑战性。介绍了地基基础和结构设计中的关键技术:如地基基础方案的优选,钢结构屋盖结构选型,拱支座推力平衡技术,以及钢拱结构的整体稳定分析等,可供类似工程设计参考。     

Partial purification and characterization of polyphenol oxidase from Chinese parsley (Coriandrum sativum)

Rates of thermal degradation and isomerization of all-trans-β-carotenes in air and in triacylglycerols were determined. Degradation of carotenes in triacylglycerols was faster than that in air. The 13-cis-β-carotene level in triacylglycerols was higher than in air. Oxidized materials of triacylglycerols probably facilitated isomerization of carotenes and, thus, degradation. Amounts of all-trans-β-carotenes and all-trans-α-carotenes in pumpkin decreased with an increase in heating time. The proportion of 13-cis-β-carotene increased after heat treatment started, probably due to thermal isomerization of all-trans-β-carotenes to cis-isomers, and to decreases in amounts of all-trans-β-carotenes and all-trans-α-carotenes in pumpkin. Effects of heating methods on proportions of isomers; however, were not different.