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121.
122.
An experimental approach to the study of the sedimentation of dispersed particles in a centrifugal field 总被引:1,自引:0,他引:1
Summary On the basis of an especially developed centrifuge, a PC-controlled separation analyser has been assembled for the continuous
registration of particles' sedimentation process in a fluid, caused by centrifugal acceleration. The system enables the parallel
investigation of up to eight samples. During the centrifugation, the radial and temporal variation of light transmission through
the samples is registered by means of a CCD line detector. Experiments were carried out with the separation analyser on manipulated
rigid and sphered red blood cells for the verification of an established one-dimensional mixture fluid model. In particular,
the influence of particle volume concentration as well as of the angular velocity on the sedimentation process was investigated.
Justification could be furnished for the one-dimensional model based on the theory of kinematic waves and shocks. In addition,
an algorithm has been developed for the experimental determination of the suspension's effective or apparent viscosity.
Received 20 March 2001; accepted for publication 23 August 2001
RID="
ID=" This work is an abridged version of a part of the first author's PhD thesis. The study was supported in part by the
German Federal Ministry of Education and Research (project 03 TOU 2063) and the foundation Deutsche Forschungsgemeinschaft
(project Le 734/1–2). 相似文献
123.
You want them to remember? Then make it memorable! Means for enhancing operations research education
In this article I summarize the main points I made in the keynote presentation of the same title I gave at the EURO XXIV conference in Lisbon, Portugal in July of 2010. Each of these points deals in some way with making communications between an operations research professional (academic or practitioner) and a student, client, subordinate, supervisor, or colleague more effective. Furthermore, each point is directly related to some realization (or epiphany) that I have had with regard to communication since I began teaching ORMS in 1984. It is noteworthy that these communications share a common objective; we are trying to facilitate learning. Since I have spent most of my career in academia, my primary emphasis is on communication with students (particularly those enrolled in introductory ORMS courses). However, I have also spent a great deal of time working on operations research problems outside of academia, either as an employee in private industry or as an operations research consultant to corporations and not-for-profit organizations, and I hope as a consequence my discussion is also relevant to those working in the practice of ORMS. 相似文献
124.
Synthesis of mevalonolactone (hiochic acid lactone) employing asymmetric epoxidation as the key-step
(R)( — )-Mevalonolactone (hiochic acid lactone)of 91–93%e.e. was synthesized from an achiral starting material employing the Sharpless asymmetric epoxidation as the key-step. 相似文献
125.
David Brynn Hibbert 《Accreditation and quality assurance》2006,11(12):647-652
A report is given on a 2-day symposium “The Hitchhikers Guide to Quality Assurance” held in Brisbane Australia, in 2005. More
than 100 representatives of field laboratories attended this educational exercise organised by the Royal Australian Chemical
Institute. 相似文献
126.
Olga Štajdohar-Pađen 《Accreditation and quality assurance》2008,13(4-5):267-270
Competence of laboratory staff is an important part of the technical competence of each laboratory. Because the speed at which
knowledge goes out of date is increasing, maintaining laboratory staff competence at an appropriate level can be a very demanding
requirement, especially for laboratories operating in a free market with little or no financial help from the state or from
the larger organisation they possibly belong to. In order to manage staff competence effectively and efficiently, a laboratory
must first define its services and the processes needed for realisation of these services. Responsibility for each step in
these processes can then be assigned and gap analysis of current competence can be performed. This article analyses the requirements
of ISO/IEC 17025 standard and gives some practical advice and solutions how to organize and manage staff competence. 相似文献
127.
Possibilities for global governance of converging technologies 总被引:2,自引:2,他引:0
Mihail C. Roco 《Journal of nanoparticle research》2008,10(1):11-29
The convergence of nanotechnology, modern biology, the digital revolution and cognitive sciences will bring about tremendous
improvements in transformative tools, generate new products and services, enable opportunities to meet and enhance human potential
and social achievements, and in time reshape societal relationships. This paper focuses on the progress made in governance
of such converging, emerging technologies and suggests possibilities for a global approach. Specifically, this paper suggests
creating a multidisciplinary forum or a consultative coordinating group with members from various countries to address globally
governance of converging, emerging technologies. The proposed framework for governance of converging technologies calls for
four key functions: supporting the transformative impact of the new technologies; advancing responsible development that includes
health, safety and ethical concerns; encouraging national and global partnerships; and establishing commitments to long-term
planning and investments centered on human development. Principles of good governance guiding these functions include participation
of all those who are forging or affected by the new technologies, transparency of governance strategies, responsibility of
each participating stakeholder, and effective strategic planning. Introduction and management of converging technologies must
be done with respect for immediate concerns, such as privacy, access to medical advancements, and potential human health effects.
At the same time, introduction and management should also be done with respect for longer-term concerns, such as preserving
human integrity, dignity and welfare. The suggested governance functions apply to four levels of governance: (a) adapting
existing regulations and organizations; (b) establishing new programs, regulations and organizations specifically to handle
converging technologies; (c) building capacity for addressing these issues into national policies and institutions; and (d)
making international agreements and partnerships. Several possibilities for improving the governance of converging technologies
in the global self-regulating ecosystem are recommended: using open-source and incentive-based models, establishing corresponding
science and engineering platforms, empowering the stakeholders and promoting partnerships among them, implementing long-term
planning that includes international perspectives, and institute voluntary and science-based measures for risk management.
相似文献
Mihail C. RocoEmail: |
128.
129.
提出一个新的考虑多年时滞的动态投入占用产出模型研究教育结构,采用阶变法处理投入产出模型的非线性系数,编制2000年教育经济投入占用产出表,计算教育规模和人力资本需求和教育经费投入,发现高级人力资本在总量上,特别是结构上的短缺是中国经济发展的一个严重问题. 相似文献
130.