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F. Kudrewizki 《Engineering in Life Science》1984,4(3):247-254
An universal consideration is proposed for calculation of the heat exchange of industrial fermenters at which the energy-intake is usual as main parameter in the formulas. On this way mathematical models developed, useful for heat transport during mixing by means of mixer with and without aeration, during boiling and for bubble column, are declared. With these models it is possible to describe Non-Newtonian fluids, which rheological conditions in the concrete apparatus is formed by the intaken energy. Stable rubbers are proposed for treatment of high viscous fluids and a half-empirical model is offered for its calculation. 相似文献
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The industrial continuous fermentation for the production of microbial protein is like any real process subject to disturbances. The considerable social expenditures involved in production make it necessary to restrict the negative consequences of these disturbances to a minimum by means of suitable measures. One such measure is the computer-aided adaptation of the static optimum. For the reaction on nonmeasurable disturbing inputs an algorithm is given containing the steps data filtering, adaption of process model and optimization, and the solution of the data-filtering problem in the widest sense by spline functions is discussed. The application of this algorithm to a specific problem of process control is demonstrated in [1]. 相似文献
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Udo Mays 《Cell and tissue research》1972,123(3):395-410
Zusammenfassung Synthese und Transport von DNS, RNS und Proteinen in einem telotrophen Ovar wurden autoradiographisch untersucht. Das Vorkommen von Endomitosen in Kernen sich differenzierender Nährzellen und des Follikelepithels können für Pyrrhocoris bestätigt werden, desgleichen der Transport von hochmolekularer RNS von den Nährzellkernen zu den Oocyten in der Phase euplasmatischen Wachstums. Ein Transport in jüngere Oocyten erfolgt nicht. Ein Beitrag des Follikelepithels zur RNS-Versorgung der Oocyten wie er für eine andere Wanze beschrieben wurde, ist bei Pyrrhocoris nicht feststellbar; gleichfalls im Gegensatz zu den Befunden an anderen Wanzen findet eine relativ schwache RNS-Synthese in allen Oocytenkernen statt. Protein wird mit unterschiedlicher Intensität in der gesamten Ovariole synthetisiert und von den Nährzellen in die Oocyten transportiert.Wie im polytrophen Ovar sind zwei RNS-Transporte unterscheidbar: Die langsamere Hauptfraktion hat anscheinend die gleiche, geringe Geschwindigkeit wie der Proteintransport; es wird daher angenommen, daß es sich um die passive Verfrachtung von Ribosomen im Strom des Euplasma handelt. Eine geringere Menge markierter RNS wird schneller durch das Cytoplasma transportiert und als messenger-RNS diskutiert.
Summary Synthesis and transport of DNA, RNA, and proteins were studied in a telotrophic ovary using autoradiography. The occurrence of endomitosis in nuclei of differentiating nurse cells and follicular epithelium can be confirmed for Pyrrhocoris and also the transport of high molecular RNA from the nurse cell nuclei into the oocytes during their phase of euplasmatic growth. There is no transport into younger oocytes. In Pyrrhocoris no contribution of the follicular epithelium to the RNA supply of the oocytes is found as described for a different Heteroptere; contrary to the findings reported for other Heteroptera, a relatively low rate of RNA synthesis is detected in all oocyte nuclei. Protein is synthesized with different intensity in all parts of the ovariole and transported from the nurse cells into the oocytes.It is possible, like in the polytrophic ovary, to distinguish between two modes of RNA transport. The bulk of the RNA seems to moove at the same low speed as the proteins, presumably representing a passive movement of ribosomes in the flow of euplasma. A smaller fraction of labelled RNA is transported faster through the cytoplasm; it may consist of messenger RNA.
Die Untersuchungen wurden z.T. mit Mitteln durchgeführt, die die Deutsche Forschungsgemeinschaft Herrn Prof. Bier zur Verfügung stellte. 相似文献
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《American anthropologist》1915,17(1):170-173
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W. Teich 《Engineering in Life Science》1988,8(5):465-469
The importance of the two-step process technology in the field of biotechnological processes is demonstrated. Its application especially is pointed out to waste water treatment. The general advantages of such processes exist in its possibility to use different strains of microorganisms in an effective way and to realize parameters of the technological process in a defined sequence. But with the application of two-step process techniques (add of biomass to the second step) an extension of retention time is connected with a decrease of yield coefficient. This disadvantage may be eliminated by an inactivation of microorganisms after the first step. The inactivation of microorganisms can be realized by increase of temperature, of pH-value or by addition of toxic substances. The inactivated microorganisms act as inert particles in the second step not utilizing substrate and oxygen. The new process regime has a lot of advantages, eg. increase of biomass concentration, increase of utilization of complexe substrates and possibility of coupling different biotechnological processes. 相似文献
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E. J. Lesser 《Reviews of Physiology, Biochemistry and Pharmacology》1909,8(1):742-796
Ohne Zusammenfassung 相似文献
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In the first part of the publication [1] an algorithm for the adaptation of the static optimum was represented. This part demonstrates the application of this algorithim to a specific problem. The problems, which are connected with the application of the choice of the object function, of making the process model available and of the realizable economic effects are elaborated. The example of the tested on-line control of a strirred tank reactor shows the advantages and disadvantages of the used algorithm. 相似文献