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The man-machine dialog is very important for the design process. In this paper a program system, based on the minicomputer KRS 4201 (ROBOTRON), is demonstrated by using an interactive graphical screen. This program system provides the opportunity to analyze and synthesize mechanisms up to 16 links. The application is demonstrated by designing a front-loader-system for a truck. Real-time animation of seven-bar linkages and coupler curves, including velocity and acceleration, are shown. 相似文献
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The kinetics of the polycondensation of sodium sulfide hydrate and 1,4-dichlorobenzene to poly(thio-1,4-phenylene) in 1-methyl-2-pyrrolidone as solvent was studied in a differential scanning calorimeter at temperatures between 220 and 280°C. This polycondensation shows an autocatalytic behavior and the kinetics can be modelled by a first order reaction up to complete conversion. This is explained by the low solubility of sodium sulfide in l-methyl-2-pyrrolidone. The concentration of sodium sulfide is regarded as being constant during the whole course of the reaction. The autocatalytic effect can be explained by the increase of the condensation rate constant at the beginning of polycondensation due to the higher reactivity of the oligomers compared to the monomers. The number- and the weight-average molecular weight of the products formed during the course of the polycondensation can be modelled by means of stochastic methods. A simple model with only two different rate constants of the condensation process is assumed. The concentration of sodium sulfide in the reactive phase is found to be 2–5% of the value of dichlorobenzene at the beginning of the reaction and remains constant nearly until the end of polycondensation. 相似文献
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Ohne Zusammenfassung 相似文献
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Aus der Darstellung der Schlackenzusammensetzungen im Quasidreistoffsystem ist die Lage der Schlacken zur Kalksättigungslinie deutlich zu erkennen. Die Sublanzenschlacken lassen den Schlackenweg während der letzten Blasminuten erkennen, durch Bodenspülung und Nachspülen wird eine geringe Annäherung an die Kalksättigungslinie erreicht. Aus der Lage der Schlacken im Quasidreistoffsystem läßt sich der Einfluß der Temperatur auf den Verlauf der Kalksättigung entlang unterschiedlicher T-X-Schnitte bestimmen. 相似文献
8.
Rainer Waser Tudor Baiatu# Karl-Heinz Härdtl 《Journal of the American Ceramic Society》1990,73(6):1645-1653
The rate of the resistance degradation of doped SrTiO3 ceramics is investigated as a function of various external and material parameters. The effects of the mutually interrelated parameters dc voltage, dc electric field, and thickness of the dielectric are described by power laws. Electron microscopic potential contrast studies show a Maxwell-Wagner polarization leading to a concentration of the electric field at the grain boundaries during the degradation. Based on this finding, the voltage step per grain boundary, ΔΘgb , is introduced as a rate-determining parameter which allows an explanation of the influence of the grain size on the degradation rate as well as the difference in the power laws for ceramic and single-crystal samples. 相似文献
9.
The disposal and re-use of spent bleaching clay from the vegetable oil processing industry is a problem of growing importance.
Although today the only practical way of removal of the spent material is disposal, extraction with organic solvents is a
well-known method of de-oiling contaminated bleaching clay. In our investigations we compare the extractibility of two different
types of bleaching clays with CO2 as a solvent. All experiments were carried out with a high-pressure extraction plant. The extraction and separation conditions,
temperature and pressure, as well as the CO2 mass flow, were varied during experiments. The aim of our investigations was a complete separation of the oil from the adsorbent.
The latter should then be re-used as bleaching clay. The oil and the bleaching clay were analyzed and tested, respectively.
The results show that oil of good quality can be recovered and the bleaching clay still has an activity approximately 50%
of fresh clay. 相似文献
10.
We present a new method for automatically proving termination of term rewriting. It is based on the well-known idea of interpretation
of terms where every rewrite step causes a decrease, but instead of the usual natural numbers we use vectors of natural numbers,
ordered by a particular nontotal well-founded ordering. Function symbols are interpreted by linear mappings represented by
matrices. This method allows us to prove termination and relative termination. A modification of the latter, in which strict
steps are only allowed at the top, turns out to be helpful in combination with the dependency pair transformation. By bounding
the dimension and the matrix coefficients, the search problem becomes finite. Our implementation transforms it to a Boolean
satisfiability problem (SAT), to be solved by a state-of-the-art SAT solver. 相似文献