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排序方式: 共有1465条查询结果,搜索用时 62 毫秒
1.
大型油船货油装卸仿真模拟装置的开发 总被引:1,自引:0,他引:1
运用计算机仿真技术和V isual C 软件设计工具,开发研制基于大型油船货油装卸系统的仿真模拟装置,以供教学与船员培训之用.探讨大型油船货油装卸仿真模拟装置的应用,介绍系统的结构以及软件的实现方法. 相似文献
2.
吴东弓 《华侨大学学报(哲学社会科学版)》2001,(2):108-113
现代油画家与古代大师的显不同在于;古代大师对使用的材料工具了如指掌,而现代画家却知之甚少。本从理论上剖析油画材料的性能和特点,阐述了油画材料技法的原则及其关键问题--光泽度、干燥速度、胶油混合技法,并指出现代油画材料技法运用所存在的新问题,对材料技法的再认识将有助于中国油画艺术的发展。 相似文献
3.
Comparison of oil and egg tempera paint systems using time-of-flight secondary ion mass spectrometry
Zachary E. Voras Kristin deGhetaldi Brian Baade Eric Gordon Glenn Gates Thomas P. Beebe 《文物保护研究》2016,61(4):222-235
Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is quickly becoming a critical tool in the field of art conservation. This technique provides high-resolution spatial maps of both inorganic and organic components located within cross-sectional samples collected from works of art. With recent advances in surface analysis, ToF-SIMS can now be used to identify specific amino acids present in protein-containing materials as well as fatty acids in drying oils. For example, the detection of the ion fragment associated with the amino acid hydroxyproline can be used to confirm the use of animal glue in a paint sample. As an analytical technique, ToF-SIMS avoids the need for derivatization/silylation reagents, with no interference by the presence of pigments. Furthermore, the layered systems that are often encountered in historical paint samples remain intact throughout the analytical procedure. This allows for the co-localization of organic and inorganic species in specific layers (e.g. egg yolk paint atop a glue ground). Because of this ability to localize the analytical signal to approximately 6?µm or less, the mass spectral information can be used to produce mass-resolved and spatially-resolve images which can be correlated to previous studies of the same samples. In this study, ToF-SIMS was used to analyze a paint cross section obtained from a painting attributed to Raphael, and another from a painting by the Sienese artist Matteo di Giovanni. 相似文献
4.
依据皂化反应原理、盐析、酸解、洗涤、蒸馏、冷榨等工艺,给出了从植物油油泥中提取固体脂肪酸和液体脂肪酸等化工产品的一般方法. 相似文献
5.
喻朝善 《重庆职业技术学院学报》2006,15(2):124-126
随着炼油结构的不断调整,加工原油品质多样化和性质复杂化趋势越来越明显。高硫高酸值原油加工过程中,蒸馏装置面临着低温部位和高温部位设备发生不同原因的腐蚀现象严重的问题;在生产工艺中强化设备防腐技术措施,提高装置长周期安全运转能力,是保证高硫高酸值原油加工的关键。 相似文献
6.
杨贤艺 《涪陵师范学院学报》2004,20(2):126-128
目前,在高师油画人体课教学中,既无统一的高师油画教材,又无独立完整的教学大纲。为此,探讨人体怎样才能成为艺术,把握表现人体的技能技巧,掌握正确的认识和观察方法,培养学生的创造性思维,对高师油画人体课教学实践有很大的促进作用。 相似文献
7.
丙烯基芥末油生产工艺研究 总被引:1,自引:0,他引:1
本文介绍了从十字花科植物芥菜种籽中提取丙烯基芥末油的方法并对其生产工艺进行了新的研究。经过多次实验验证了文献记载的工艺“水解——蒸馏法”在常温常压下出油率低,进而根据影响反应的关键探索出了可行性提油生产工艺“水解——油萃法”。 相似文献
8.
程林新 《新疆师范大学学报(哲学社会科学版)》2003,24(2):153-154
当今的油画作品,在各种绘画学科相互渗透和影响下,材料在作品中的运用更加广泛,研究绘画材料在作品中的使用,以及材料与作品的构成关系,在当代的油画作品中应当引起重视。 相似文献
9.
Yves Blieck Ilse Ooghe Chang Zhu Koen Depryck Katrien Struyven Bram Pynoo 《Studies in Continuing Education》2019,41(1):36-60
Quality models for online and blended learning (OBL) have mainly been developed in higher education. The literature indicates that these models are often conceptualised from the providers’ perspective. What is important for the quality of OBL from the students’ perspective has recently received increased attention in the literature. Consensus among stakeholders about students’ quality needs is useful to support dialogue between professionals to strategically adopt OBL and to ensure that the needs of students are met. This study aims to validate a quality instrument for OBL, taking a set of 74 quality indicators and analysing them in terms of seven success factors (credibility, accessibility, transparency, flexibility, interactivity, personalisation, productivity). The Delphi method was selected as most suited. Participants from adult education were asked to indicate on a 7-point Likert scale to what extent the indicators add to OBL quality to meet students’ needs. After four Delphi rounds, the participants agreed on definitions of success factors and 30 indicators. The results are useful for institutions, ministries of education and external quality assessment agencies to assess the quality of OBL and can support institutions to implement improvement actions to ensure that the needs of students are met. 相似文献
10.
A competence-based approach was applied to a blended learning on line distance training in the Euroinno EU project aimed at vocational training in building automation. The current paper describes the experience gathered during the learning process and the definition of the curriculum. A number of issues emerged during the sessions concerning regional differences among the various European partners involved in the learning. Refusal to accept e-learning approaches has been considerable among teachers and students in piloting building automation courses, and mainly related to four factors in the tradition of adult education: curriculum tradition, oral tradition, lack of confidence in technical solutions to educational matters and lack of experience with the media. 相似文献