Highland amphibians and extremely diluted thyroxine: pre-experiment storage at low temperature

Introduction: In the course of more than two decades of experimental work on a model with amphibians and extremely diluted thyroxine, one experiment in particular, investigating the effect of an ultra-high dilution of thyroxine (T30x) v analogously prepared water (W30x) in amphibians from highland biotopes, was found to be reproducible. A total of 22 experimental runs were performed between 1990 and 2011, 15 by the initial researchers and 7 by altogether 5 independent researchers (1-5). In most of these (the sole exception being two performed and reported by the initial team) a trend was found of T30x-animals developing more slowly than W30x-animals. Pooled T30x values obtained by the initial team were 10.1% lower than W30x values (100%) (p < 0.01), and pooled T30x values from the 5 independent researchers were 12.4% lower (p < 0.01). The purpose of this study was to test the hypothesis that storing the animals at 4°C prior to the experiment does not influence (i.e. inhibit) the effect of T30x. Cooling here seemed to be a promising means of facilitating the transport of the highland larvae to laboratories and of synchronizing experiments. Methods: The original protocol was followed, but animals were stored at 4°C for several days prior to the experiment. Results: In contrast to the majority of previous experiments, no clear trend was found of T30x values being different from W30x values, i.e. of animals developing more slowly under the influence of T30x (p > 0.05). Conclusion: This experiment failed to reproduce the previously observed inhibiting effect of ultra-high diluted thyroxine on highland amphibians. The hypothesis that storage of the animals at 4°C does not influence the effect of T30x could not be proven; in contrast, it may be that this intermediate cooling down of the larvae is responsible for the failure of the replication.

DEVELOPMENT OF THE COMBINED RESERVOIR OF MIXTURE OF TECHNICAL COMBUSTIBLE LIQUIDS AS COMPONENT OF ENVIRONMENT PROTECTION TECHNOLOGY

In this study the development, analysis and description of the sche­me of environment protection technology for the oil storage were carried out. The proposed scheme is provided for the utilization of vapors of technical combustible liquids stored at the enterprise, namely diesel fuel, gasoline and motor oil, formed during the manifestation of the phenomena of small and large reservoir breathing in significant quantities. Set of initial data and the mass hour­ly emission of such vapors into the en­vironment were obtained according to an improved approach. Development of a high-pressure storage reser­voir for such vapors as the executive device of environmental protection technology for the oil storage according to an improved approach was carried out. Parameters of the reciprocating compressor, which distills the mixture of such vapors from the low-pressure storage reservoir to the high-pressure sto­rage reservoir, compressing them, was selected. Calculation of the reservoir wall thickness ba­sed on the theory of strength of closed solid shells was carried out taking into account the mechanical properties of the wall material, namely steel 60, and the value of the pressure of the gaseous fluid in it. Magnitudes of weight of the deve­loped reservoir and the cost of materials for its manufacture were determinated. Design of a combined reservoir for the ac­cu­mu­lation of a volley of a mixture of such vapors with a system of intermediate cooling of the mixture after its compression by a reciprocating compressor and the pos­sibility of heating the condensate in the reservoir was de­ve­loped.

A temperature-dependent switching of the exchange bias effect from negative to positive under a fixed intermediate cooling field

An interfacial coupling origin of the exchange bias effect (EBE) is a novel phenomenon due to its technological and fundamental importance.

Mechanical and Thermal Influences on Microstructural and Mechanical Properties during Process-Integrated Thermomechanically Controlled Forging of Tempering Steel AISI 4140

Thermomechanical treatment (TMT) describes the effect of thermal and mechanical conditions on the microstructure of materials during processing and offers possible integration in the forging process. TMT materials exhibit a fine-grained microstructure, leading to excellent mechanical properties. In this study, a two-step TMT upsetting process with intermediate cooling is used to demonstrate possibilities for a process-integrated treatment and corresponding properties. A water–air-based cooling system was designed to adjust different phase configurations by varying the target temperature and cooling rate. Four different thermal processing routes and four combinations of applied plastic strains are investigated in standardized mechanical tests and metallographic analyses. The applied TMT results in a finely structured bainitic microstructure of the investigated tempering steel AISI 4140 (42CrMo4) with different characteristics depending on the forming conditions. It can be shown that the demands of the standard (DIN EN ISO 683) in a quenched and tempered state can be fulfilled by means of appropriate forming conditions. The yield strength can be enhanced up to 1174 MPa while elongation at break is about 12.6% and absorbed impact energy reaches 58.5 J without additional heat treatment when the material is formed after rapid cooling.

Optimal Design of Thermally Stressed Turbocharger Blade Using Response Surface Method

RI turbine is a device that rotates the shaft by the working fluid enters the radial direction and exit in the axial direction. It is mainly used in automobile turbochargers and helicopters. Turbocharger is an important part of reducing fuel use as part of the vehicle’s power source. It is largely divided into compressor part and turbine part, and rotates the compressor by the power received from the turbine part. The gas emitted after combustion in the engine is the working fluid and the driving force for rotating the turbine. In this process the turbine is directly exposed to hot combustion gases. There is an intermediate cooling process, but the trend is to reduce and simplify it. Therefore, thermal stress analysis and optimal design process for the blades of the turbocharger turbine is required. In this study, the optimal design of turbine blade was carried out to alleviate thermally vulnerable areas without compromising efficiency through CFD (computational fluid dynamics) and RSM (response surface method). After preliminary design, numerical analysis was used to identify thermal weakness, and the optimal design was carried out with vulnerable area and efficiency as output parameters. As a result, a blade design that can lower the temperature from the weakness was derived, and a thermal optimization design process of the RI turbine was presented.

Making use of geothermal brine in Indonesia: binary demonstration power plant Lahendong/Pangolombian

This paper describes a novel concept for integrating binary plants at a geothermal site which has been realized within a demonstration project in Indonesia. By using an intermediate hot water and an intermediate cooling water cycle it is possible to integrate a fully-automated binary plant with flexible operation in an existing, predominantly manually operated geothermal field. The paper gives technical component details and describes specific design considerations of the demonstration power plant. Furthermore operational data and experiences are shared. Current binary plant operation is characterized by many starts and stops because of several technical challenges, e.g. electrical grid conditions, as well as by off-design conditions. The proven maximum power capacity until now is approximately 400 kW. By means of a numerical model it is shown that the design capacity of 500 kW can be reached.

Determination of Correlation Between Composition, Rolling Parameters and Mechanical Characteristics of the Hot Rolled Steels

The controlled lamination of thick sheets involves the use of algorithms for choosing the rolling parameters: the initial heating temperature, the lamination scheme (the distribution of the total thickness reduction on each rolling cage, the number of passes through each cage and the distribution of the thickness reduction on each passage, intermediate cooling - cooling time and speed), and the temperature of the product obtained at the end of the rolling. The complexity of the phenomena, which occur during the hot plastic deformation process and which must be sufficiently well mastered in order to obtain reproducibly the technical specifications imposed on the products with different destinations, is the justification for this work. The data provided by Arcelor-Mittal Galati was used to obtain the mathematical model. Equations that correlate the main mechanical characteristics with the chemical composition of the steel and the parameters of the hot rolling pattern used are presented.

Effect of Cooling Rate on the Eutectoid Transformation in Compacted Graphite Cast Iron

Differential thermal analysis has been used to characterize the effect of cooling rate on the eutectoid transformation of a compacted graphite iron. The samples were machined out from an as-cast thermal cup, austenitized at 950°C and then cooled to room temperature at various rates within the range 1−55.5°C/min. It was found that even at the highest investigated cooling rate, significant amounts of ferrite could be observed. When comparing the microstructure before and after Nital etching on samples cooled at intermediate cooling rates, it appeared that ferrite formed preferentially along the worms. This is discussed in terms of graphite shape and microsegregation and this latter seems prevalent. Finally, analysis of the thermal records was performed to characterize the temperatures for the start of the stable and metastable eutectoid reactions which confirms the eutectoid transformation sets up in compacted graphite irons as in lamellar and spheroidal graphite irons.