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81.
猪皮胶原肽-锌螯合物的制备工艺研究 《山东科学》2010,33(3):53-61
研究猪皮胶原肽-锌螯合物的制备工艺。以猪皮为原料,制备猪皮胶原肽-锌螯合物;以螯合率为指标,研究了猪皮胶原肽与锌质量比、pH、温度、时间对螯合率的影响;通过单因素试验、响应面法试验考察优化猪皮胶原肽的富锌工艺。结果显示,猪皮肽-锌螯合的最佳工艺为猪皮肽与锌质量比2:1,螯合pH 7.0,螯合温度50 ℃,螯合时间50 min,在此条件下,试验螯合率最佳,为69.27%,与模型预测值69.92%相近。该研究为新型生物肽 锌螯合物的研制、猪皮的高值化利用提供了依据。 相似文献
82.
Lars-Göran Johansson Keizo Matsubara 《Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics》2011,42(3):199-210
String theory has been the dominating research field in theoretical physics during the last decades. Despite the considerable time elapse, no new testable predictions have been derived by string theorists and it is understandable that doubts have been voiced. Some people have argued that it is time to give up since testability is wanting. But the majority has not been convinced and they continue to believe that string theory is the right way to go. This situation is interesting for philosophy of science since it highlights several of our central issues. In this paper we will discuss string theory from a number of different perspectives in general methodology. We will also relate the realism/antirealism debate to the current status of string theory. Our goal is two-fold; both to take a look at string theory from philosophical perspectives and to use string theory as a test case for some philosophical issues. 相似文献
83.
对日本著名科学家如何注重科技哲学经典著作的研究进行了评述,指出:他们对恩格斯的《自然辩证法》出版了多种译本,重视联系现代科学发展的实际,探讨其精神实质,纷纷发表自己的学习体会,并在此基础上,运用科技哲学经典著作的思想,分析了科技哲学的一些基本理论问题,提出了许多独到见解,为我国科技哲学研究提供了有益的启示。 相似文献
84.
新一轮基础教育数学课程改革,把在数学教学中培养学生的数学思想方法提高到十分显著的地位.笔者从基础教育数学课程“三位一体”的目标出发,探讨数学思想方法教学的意义,进而探索培养高师学生数学思想方法教学意识的方法与途径. 相似文献
85.
Dealing with coercion: Critical Systems Heuristics and beyond 总被引:1,自引:1,他引:0
Gerald Midgley 《Systemic Practice and Action Research》1997,10(1):37-57
This paper begins with an introduction to the philosophy and methodology of Critical Systems Heuristics (CSH). Following this,
various citicisms of CSH are reviewed. One particularly important criticism is that CSH should not be seen as a replacement
for other systems approaches, but as complementary to them. It is this idea of complementarity that has led several Critical
Systems thinkers to take CSH, along with a number of other systems methods, and try to show that they are most appropriately
used in different contexts. CSH, it is said, is at its most useful when we are confronted with coercive situations. However,
in this paper it is argued that coercion is usually characterised by closure of debate. Therefore CSH, which depends upon
the possibility of communication (or arbitration) between stakeholder groups, becomes redundant when coercion is experienced.
It is further argued that coercion can only be addressed adequately by widening our definition of systems practice to include
campaigning and direct political action. There is still considerable scope for developing these areas in the systems domain. 相似文献
86.
本文通过分析目前大学英语教学存在的问题,就大学生英语素质的培养探讨了大学英语教学的改进办法。 相似文献
87.
高新宇 《沈阳大学学报:自然科学版》2006,18(1):6-9
从新制度经济学的基本理论入手,分析了新制度经济学对传统经济学假设的批判,进而详细阐述了新制度经济学的方法论特征,并从中得到启示。 相似文献
88.
介绍了战略决策专家系统中一种新的知识表示方法“分解-综合”知识表示法,给出了“分解-综合”表示法的应用实例,指出了“分解-综合”表示法的优点. 相似文献
89.
In a previous paper the author introduced a concept called qualifying function as a conceptual tool for modeling and design. The concept was incorporated into the modeling phase of soft systems methodology (SSM), with the purpose of addressing some of the criticism directed toward the methodology, such as its tendency to result in regulatory, rather than radical, agendas for change. It was argued that the concept had the potential to help people in a particular problem situation to view the situation from new and different perspectives and that it could enrich the conceptual models by giving the transformation process a direction. The aim of this paper is to apply the concept, embedded in SSM, to a case study involving two projects, focused on creating new work opportunities, to explore the practical applicability and usefulness of the concept, both in general and as a part of the modeling phase of SSM. 相似文献
90.
基于模型的系统工程在航空发动机控制设计中的应用 总被引:1,自引:0,他引:1
基于模型的系统工程(MBSE)采用模型的表达方法描述系统的整个生命周期过程中需求、设计、分析、验证和确认等活动,以其无歧义、模块化、可重用、可追溯等优点迅速覆盖了航空航天、船舶等相关工程领域。总结了MBSE的方法论、建模语言和建模工具,并探索适合航空发动机功能建模的解决方案。 相似文献