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[en] Considerable advances have been attained during the last decade in the theoretical and experimental investigation of electrode phenomena in high-pressure arc discharges, in particular, in low-current arcs that occur in high-intensity discharge lamps. The aim of this paper is to deliver a concise review of the understanding achieved and modelling methods developed
[en] Modern high-pressure discharge lamps are forced to provide instant light and hot relight capabilities - if possible at lower power units. A detailed understanding of the warm-up of high-pressure discharge lamps is therefore required. Complex fluid model codes were developed for the past years including more and more processes like two-dimensional treatment of convection trying to provide a more comprehensive and consistent description of high-pressure discharge lamps. However, there is a lack of experimental data to examine the performance of these models. This work provides a very complete set of geometrical, electrical, spectroscopic, and thermographic data according to the warm-up of a high-pressure mercury discharge lamp that is compared to the results of a state of the art fluid code. Quantitative agreement is achieved for single parameters like wall temperatures. But the paper also reveals the need for further investigations and improvements of the code.
[en] Photochemical degradation of dimethyl phthalate (DMP) in Fe(III)/tartrate/H2O2 system was investigated utilizing fluorescent lamps as the primary light source. Effects of initial pH, light source, and initial concentration of each reactant on DMP photodegradation was examined. The results show that the system was able to effectively photodegrade DMP utilizing visible light. Fluorescent lamp, halide lamp, UV lamp and sunlight could all be used as the light sources. The optimal pH ranged among 3.0-4.0 for the system. Increases of the initial concentrations of Fe(III) and H2O2 accelerated the photodegradation of DMP, whereas excessively high initial tartrate concentration resulted in the decrease of photodegradation efficiency and rate of DMP
[en] The decay of fluorescence on a range of commercially available papers was investigated by exposing them to a 1KW tungsten lamp for a total of 10 hours, with the samples removed for measurement at regular intervals. The results indicated that FWA decay is more rapid on papers with higher FWA efficacy. Only the papers with minimal FWA efficacy reached a plateau after which there was no further significant decay.
[en] A new type of photoelectric detection device was developed which had the characters of ultra-fast, wider dynamic linear range. It was used for the measuring ultra-fast pulse signal. The characteristic parameters of device were studied by pulse xenon lamp and laser etc. The experimental results indicate that the phototube has ultra-fast time-response. Its further applications will be found in the field of sub-nanosecond pulse measurements. (authors)
[en] This paper addresses the problem of energy saving in the residential sector and its relation to behavior. However, we know little about the mechanisms explaining consumption and use. The aim is to explore the behavioral elements behind patterns of use, so that consumption can be explained and saving possibilities identified. The study is based on detailed, metered data from an ongoing monitoring study. A larger sample from that study made testing of two hypotheses possible. Yet, many factors remain hidden and must be traced among the habits of households. The major part of the article is devoted to an exploration into what other variables are at work. This was done by studying the electricity consumption of seven households closely. Here, different sources of information from each household were combined: detailed, metered data for each lamp or fixture; data from interviews regarding habits; and observations of natural light and lighting equipment at visits. This information from combined sources was used to detect meanings of use and relationships with consumption. What has been found here must be translated to measurable variables and tested on representative samples of populations. This study offers information on these variables identified and how to interpret them
[en] In this paper, a method is tested to measure temperatures in high-temperature welds. Protective glass was installed between an infrared thermal imaging camera and a heat source, and temperature compensation was applied to the measuring instruments. When the temperature of halogen lamps was taken in real-time and measured by the thermal camera, the temperature was found to be almost invariant with the distance between the camera and heat source. The temperature range could be predicted, through correlations with the thickness of the protective glass and the measured distance. This study suggests that the temperature measurement of welds obtained by using an infrared thermal imaging camera is valid, through experimental testing of heat sources.
[en] This paper summarizes different kinds of heat sinks on the market for high power LED lamps. Analysis is made on the thermal model of LED, PCB and heat sink separately with a simplified mode provided. Two examples of simulation are illustrated as a demonstration for the thermal simulation as guidance for LED lamp design. (semiconductor devices)
[en] The laboratory replication of the greenhouse effect appears deceptively simple. Using a cubic box illuminated by an ordinary lamp, one may show some of the phenomena present in the climate system. It is nonetheless necessary to use a lot of physical ingenuity to understand the complex interaction of radiative and convective phenomena which characterizes such a simple system. In this paper we introduce a critical review of some experiments in the literature and suggest a new and original experimental set up using an unusual gas; in this way we overcome some of the limitations of the typical laboratory experiment, confirming the possibility of using it in educational physics laboratories without any lack of physical plausibility. (paper)
[en] Complete text of publication follows. The basics of Atomic Spectroscopy were settled in the middle of the 19th century but it lasted a hundred years till first commercial flame and graphite furnace AAS Systems became available for routine work. During the last decades of the 20th century this technique became an established method for metal analysis. All systems had one in common, which is the necessity of a single element lamp with narrow emission lines. Main developments were made in optimising the way of background correction, in making the handling simpler and introducing more advanced accessories. Furthermore, the sample introduction systems for liquid samples were expanded by solid sampling systems for many applications. A completely new concept for routine Atomic Absorption Spectrometers was introduced by Analytik Jena in 2004: After a long journey, continuum radiation sources have finally arrived. The combination of a continuum radiation source with a high resolution optics and a CCD detector in these systems is setting the standard for Atomic Absorption Spectrometers in the 21st century. For the first time the vicinity of the absorption line becomes visible. This makes the method development and the evaluation of measurement results more easy. Molecular structures of non-metals become visible what broadens the application range. The new instrument is ready to measure every element at every absorption line immediately. A huge stock on single element lamps belongs to the past.