Types Of Experimental Apparatus Research Articles

Visualization of flow conditions inside spiral jet mills with different nozzle numbers– Analysis of unloaded and loaded mills and correlation with grinding performance

Plenty of operational and geometric parameters have effects on spiral jet milling. Changes in the parameters cause distinctions in the flow conditions inside the mill and thereby also lead to consequences regarding the milled product. A new type of experimental spiral jet mill apparatus with almost entire optical accessibility enables a very convenient variation of the operational and geometric parameters as well as the determination of the flow conditions inside the spiral jet mill via non-invasive optical methods. Particle Image Velocimetry (PIV) measurements with diethylhexyl sebacat (DEHS) tracer droplets as well as solid barium sulphate micro particles were carried out to investigate the flow conditions inside the spiral jet mill. The differences between the net milling gas velocity fields and the velocity fields of loaded spiral jet mills were exposed. With the mill being loaded, the comminution zone decreases in the horizontal direction as well as decreases and deflects in the vertical direction. Besides, the analysis of the velocity fields inside the mill apparatus showed that decreasing milling nozzle numbers lead to increasing velocities inside the spiral jet mill, even if the mass flow rate of the gas supply is kept constant and the nozzle jet velocity is limited to sonic velocity at choked flow. With decreasing milling nozzle numbers, broader comminution zones and increasing lengths of the milling jets were investigated. As a consequence, a better grinding efficiency was expected and also confirmed with decreasing milling nozzle number by grinding experiments, as the new type of experimental apparatus was constructed in a fully operative way concerning the grinding ability.

Effect of Water Table Rise on Migration and Transformation Law of Nitrate under the Condition of Rainfall in Saturated - Unsaturated Soil Layer

In this experiment, we simulated the migration and transformation law of nitrate under the condition of water table rise caused by rainfall in Changping District of Beijing. Two types of experimental apparatus were used in the experiment to simulate the distribution of NO3--N, NO2--N and NH4+-N, which were named soil column 1 and soil column 2. Soil column 2 was under the condition of rainfall and soil column 1 was for comparison. It took 50.3 hours for the experiment during which simples were taken and tested. The test items were the concentration of NO3--N, NO2--N and NH4+-N. The results indicated that (1) In unsaturated zone, the influence of leaching caused by rainfall on the concentrations of NO3--N and NH4+-N were significant. The decreasing range could reach to 95.9% and 90% which means that it was easily to lead to the contamination of groundwater. In saturated zone, NO3--N concentrations were mainly influenced by dispersion and could achieve balance between the dilution and dispersion with the increase of rainfall. The increasing range of NO3--N concentration was large, and the value could reach to 675%. In addition, the NH4+-N concentration had a slight trend of decrease. (2) Under the condition of rainfall, NO3--N concentrations increased in saturated zone, decreased in the path of water table rise and unsaturated zone. The NH4+-N concentrations had a decreasing trend in saturated-unsaturated zone. (3) NH4+-N concentrations in medium sand were more easily influenced by leaching from rainfall than those in silt.

Vaporization and Conversion of Ethanolamines used in Metalworking Operations

ObjectivesThis study examined how ethanolamines (EAs) with the same functional alcohol group (HOCH2CH2), such as mono-EA (MEA), di-EA (DEA), and tri-EA (TEA), in water-based metalworking fluids (wbMWFs) are vaporized, condensed, and transformed by heat generated during metalworking.MethodsTwo types of experimental apparatus were manufactured to achieve these objectives.ResultsVaporization tests using a water bath showed that the vaporization rate increased markedly from 0.19 mg/m2·min at 23.5℃ to 8.04 mg/m2·min at 60℃. Chamber tests with a heat bulb revealed that "spiked" MEA was fully recovered, while only 13.32% of DEA and no TEA were recovered. Interestingly, non-spiked types of EAs were detected, indicating that heat could convert EAs with more alcohol groups (TEA or DEA) into other EAs with fewer group(s) (DEA or MEA). The EA composition in fresh fluid was 4% DEA, 66% TEA, and 30% MEA, and in used fluids (n = 5) was 12.4% DEA, 68% TEA, and 23% MEA. Conversion from TEA into DEA may therefore contribute to the DEA increment. Airborne TEA was not detected in 13 samples taken from the central coolant system and near a conveyor belt where no machining work was performed. The DEA concentration was 0.45 mg/m3 in the only two samples from those locations. In contrast, airborne MEA was found in all samples (n = 53) regardless of the operation type.ConclusionMEAs easily evaporated even when MWFs were applied, cleaned, refilled, and when they were in fluid storage tanks without any metalworking being performed. The conversion of TEA to DEA and MEA was found in the machining operations.

Measurements of bubble point pressure for CO 2 + decane and CO 2 + lubricating oil

Two types of experimental apparatus were designed to measure bubble point pressure for supercritical carbon dioxide (CO 2) + lubricating oil. One was based on a synthetic method, and the other was on a recirculating method. An oscillation U-tube densimeter was also equipped with the recirculating type apparatus to measure the liquid density. Ensuring the reliability of the experimental data, bubble point pressure was measured for CO 2+decane (C 10H 22) at 344.3 K. The experimental data of the bubble point pressure and the liquid density were agreed well with the literature. Lubricating oil employed was polyalkylene glycol type one for refrigerators, commercially named PAG-1. The bubble point pressure and the liquid density were measured for CO 2+PAG-1 at 344.3 K. The experimental data were correlated with Peng–Robinson (PR) equation of state.

Detection of Anomalous Elements, X-Ray, and Excess Heat in a D2-Pd System and Its Interpretation by the Electron-Induced Nuclear Reaction Model

A new type of experimental apparatus is developed to induce continuous diffusion of deuterium, in which an electrochemical cell for calorimetry and a vacuum chamber for nuclear measurement are divided by a Pd sheet. Continuous X rays ranging from 10 to 100 keV and neutron and excess heat production are observed using the apparatus. Titanium atoms are detected on the surface where deuterium atoms pass through on Pd cathodes after electrolysis. Quantitative discussion shows that the detected Ti atoms cannot be explained by contamination. An electron-induced nuclear reaction (EINR) model for explaining the obtained experimental results is introduced. Experimental support of the EINR model is demonstrated by using multilayer cathodes, in which a layer containing Ca is placed at the near surface of Pd, based on the EINR model.

GAS TRANSPORT IN THE HAEMOLYMPH OF ARACHNIDS - OXYGEN TRANSPORT AND THE PHYSIOLOGICAL ROLE OF HAEMOCYANIN

Oxygen equilibrium curves and the relationships between the partial pressure of CO2 and pH were determined for the haemolymph of the arachnids Eurypelma californicum, Pandinus imperator and Cupiennius salei. A new type of experimental apparatus was constructed, tested and used to make these measurements on small undiluted cell-free haemolymph samples. Most of its components were made in our workshop and were inexpensive. The apparatus proved to be very reliable as demonstrated by control (oxygen concentration) experiments. In previous reports on O2 equilibrium curves of E. californicum haemocyanin, Tris­HCl buffer was used to set the pH, whereas in our experiments, pH was adjusted by altering the partial pressure of CO2. The O2 concentration measurements demonstrate an increase in oxygen affinity of E. californicum haemocyanin when using Tris­HCl buffer. The position and shape of the O2 equilibrium curves of E. californicum and P. imperator haemocyanin show a distinct dependency on pH. Oxygen affinity is lower in E. californicum and cooperativity changes with pH in E. californicum, but not in P. imperator. Oxygen transport in the haemolymph of E. californicum during rest, activity and recovery was calculated on the basis of the O2 equilibrium curves of undiluted haemolymph. Apart from oxygen transport, there are indications that haemocyanin is also involved in other physiological processes. For example, it may function as a storage protein.

Gas production by almond shell pyrolysis at high temperature

The production of gases from almond shell pyrolysis at high nominal temperatures (700–900°C) is discussed, taking into consideration the gaseous products formed by the primary and secondary reactions respectively. Two types of experimental apparatus have been used: (a) an analytical Pyroprobe 100, where the primary reactions take place and in which the cracking of the primary tars evolved can be considered negligible; (b) a fluidized sand bed reactor, where the biomass is decomposed inside the sand bed and the tars formed are cracked in the upper part of the reactor over the sand bed. Both reactors have proved to be suitable for studying the primary and secondary pyrolysis reactions, respectively. The evolution of the primary hydrocarbons and primary carbon monoxide is suggested to take place by very temperature-sensitive mechanisms, whereby the other oxygenated compounds, carbon dioxide, water, acetic acid and methanol + formaldehyde, are formed by mechanisms involving depolymerizations. On considering the formation of the secondary products, correlations between the yields of carbon oxides and hydrogen as well as between methane and ethylene were observed.

Mechanical effects on rates of hemolysis.

Empirical studies were conducted on how rates of hemolysis were influenced by mechanical factors, such as shear, turbulence, agitation, pressure fluctuation, and bubbling, in five types of experimental apparatus: rotating cylinder, rotating disks, agitated vessel, pressure pulsator, and bubble columns. Our data indicate, at least qualitatively, that an important mechanical factor controlling rates of hemolysis in practical devices, in which blood does not flow in thin channels or capillaries, is the turbulent stress in the bulk blood, rather than the shear at the blood-solid interface.

Photoresponse in Relation to Experimental Design in Sibling Sympatric Species of Drosophila

Photoresponses of isofemale lines of Drosophila pseudoobscura, D. persimilis and D. miranda captured in two locations were compared in two types of experimental apparatus, an open field and a Y-tube. Photoresponses were significantly more negative in the open field than in the Y-tube. Responses in one apparatus were unrelated to the responses in the other. The sibling sympatric species from each location could be distinguished by their light responses irrespective of the experimental design. The populations of D. pseudoobscura from the two locations were significantly different in both designs. These behavioral differences must be attributable to different genetic determinants. INTRODUCTION Rockwell and Seiger (1973a) in a review of photoresponse in the genus Drosophila noticed that in the past experimental designs tend to fall into one of three classes. In Class I, photoresponse is measured as the movement or distribution of the individuals relative to a directed light source. For example, in the very first paper that used fruit flies for research, Carpenter (1905) measured photoresponse in terms of movement toward a light source and distribution of flies in a light gradient. In Class II, photoresponse is measured by the distribution of flies in an open field in which areas of the field differ in quality or intensity of light. Movement of the flies is in a plane perpendicular to the light source (Rockwell and Seiger, 1973b; Rockwell et al., 1975). In Class III, photoresponse is measured by the frequency of choice flies make when they reach a juncture of two light intensities. The two lights may be provided by light directed at the choice point (Hirsch and Boudreau, 1958; Pittendrigh, 1958) or by a light shining perpendicular to the plane of movement (Lewontin, 1959; Dobzhansky et al., 1969; Seiger and Seiger, 1979). It is difficult to make generalizations about photoresponse using different experimental designs. It may be that different experimental designs elicit different photobehavior from any given population of Drosophila. This possibility was studied in the current research. MATERIALS AND METHODS Drosophila pseudoobscura, D. persimilis and D. miranda are sibling species of the obscura species group within the subgenus Sophophora of the genus Drosophila (Dobzhansky and Epling, 1944). The isofemale lines (each started from one female caught in the wild) used in this study were kindly provided by Dr. Francisco Ayala, University of California, Davis. This study of five isofemale lines each of D. pseudoobscura and D. persimilis from MacDonald Ranch, Calif., and D. pseudoobscura and D. miranda from Mather, Calif., began with the F2 generation and took somewhat less than a year to complete. All strains were cultured in half-pint milk bottles using a cream-of-wheat and raisin medium at a temperature of 20 zt 1C under constant illumination of 3.0 ergs/cm2-sec.

The use of controlled experimental ecosystems: A review

During the past 20 years, the controlled experimental ecosystem has found wide-spread use in marine sciences. Uses have included the study of natural ecology, environmental pollution and computer model analysis. In all these roles, the experimental ecosystem serves as a model of nature and results can be used to obtain greater insight into the oceanography of the sea. Four different types of experimental apparatus are described, and experimental procedures and results are reviewed and discussed.