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81.
ABSTRACTThe paper deals with a study of tensile strength and disintegration time of compacts made from silicified microcrystalline celluloses, Prosolv SMCC 90, and Prosolv HD 90, in dependence on compression force, addition of two types of lubricants, and two active ingredients. The lubricants were magnesium stearate and sodium stearyl fumarate in a concentration of 0.5%, the active ingredients being ascorbic acid and acetylsalicylic acid in a concentration of 50%.Prosolv SMCC 90 proved to be better compatible than Prosolv HD 90; the compacts were of higher strength, which was markedly increased with increasing compression force. Prosolv HD 90 was more sensitive to additions of lubricants, and a greater decrease in strength was recorded due to the influence of sodium stearyl fumarate. The effect of lubricants on the strength of compacts in the presence of active ingredients was not identical. The disintegration time of compacts from Prosolv HD 90 without as well as with lubricants was shorter than from Prosolv SMCC 90 and was increasing with increasing compression force. Disintegration time was increased with added lubricants, and it was markedly shortened by addition of active ingredients. Compacts containing ascorbic acid possessed a shorter disintegration time than those containing acetylsalicylic acid, and it was not markedly influenced by the presence of lubricants. 相似文献
82.
Gas evolution in primary alkaline cells depends on discharge time. This dependence can be so strong that acceptable volumes of gas are evolved in cells when discharged over relatively long periods, whereas shorter times may lead to gassing beyond the limits of the cell design. The dependency of gassing on discharge time was investigated for a number of commercial cells and for different zinc-alloy powders. An indication of a relation between certain alloying elements and the gas evolution at short discharge times was found. The most important result of the investigations, however, was the development of a modified zinc powder production process which leads to zinc powders with reduced gas evolution rates for both short and long discharge times. 相似文献
83.
Petra Heinze 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2009,228(4):43-44
Currently, the Bundesamt für Verbraucherschutz und Lebensmittelsicherheit (BVL) is running the project ”Development of a German
Molecular Register as a web-based software application”. The Molecular Register shall integrate regulatory, phenotypic and
molecular information on GMO, and allow the use of established bioinformatics tools in support of the Competent Authorities
in their responsibilities according to Directive 2001/18/EC and Regulations (EC) No 1829/2003 and (EC) No 1830/2003. 相似文献
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Hermann Petra M.; Wildering Willem C.; Bulloch Andrew G. M. 《Canadian Metallurgical Quarterly》2000,114(2):410
This study investigated the role of experience in recovery of pulmonary respiration during axonal regeneration in Lymnaea stagnalis. Pulmonary respiration occurs when snails break the water surface and open the lung orifice, the pneumostome. It was shown that axotomy of all the axons innervating the pneumostome and surrounding area prevents the occurrence of lung respiration in 69% of snails. In the remaining 31%, lung respiration persisted, indicating that peripheral components alone are capable of initiating pneumostome openings and closures. Five weeks postsurgery, all snails with previous nerve crushes showed opening of the pneumostome with normal latency after breaking the water surface. However, prevention of pulmonary respiration during the recovery period dramatically changed the recovered behavior. Thus, experience in pulmonary respiration during axonal regeneration plays a role in the recovery of this behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Steven Visser Inge Kerssensvan Drongelen Petra C. De WeerdNederhof James Reeves 《Creativity & Innovation Management》2001,10(4):259-268
At NIAB, a UK based company that provides research, services and information to the agricultural and food sector, a system has been designed that helps to assess and manage the growing research programme of the company. Since the company was ‘privatised’ four years ago, research activities have increased and moved away from solely applied research to a mix of applied and more fundamental research. Being a key element of the new developed company strategy, research now plays an increasing important role in broadening the scope of the company and keeping current services competitive by driving innovation. All research at NIAB is externally funded. In this paper we report on the process to design NIAB’s performance measurement system, for which the Performance measurement system Systematic Design Approach was used. The design process was started with an elaborate structured problem analysis of the research process and its inter and extra–organisational context. Based upon this analysis, firstly a conceptual and secondly a detail design of a performance measurement system was made. To maximise the leverage from research, the system has been designed to optimise the value delivered to the funder as well as the value delivered to internal customers in the form of knowledge that drives innovation. 相似文献
90.
The extent to which technical barriers to international trade caused by non-acceptance of chemical measurement results can
be removed, largely depends on the success in building up national and international traceability structures also in metrology
in chemistry. Achieving metrological comparability of measurement results requires the definition of metrological calibration
hierarchies providing metrological traceability chains which enable the establishment of metrological traceability of measured
quantity values to a common metrological reference [1]. For pH, over the last decade, work has been carried out in a number
of countries to build up meteorological calibration hierarchies within a national framework. An overview on the metrological
traceability chain for pH is given with focus on the primary measurement procedure of pH. 相似文献