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731.
Werner Höhne 《Theoretical and Applied Climatology》1961,11(1):126-134
Zusammenfassung Es wird gezeigt, daß es möglich ist, auf galvanischem Wege Thermosäulen zu erzeugen, deren Empfindlichkeit von der Bezugstemperatur unabhängig ist. Der galvanische Niederschlag muß hierbei eine bestimmte Stärke besitzen, die vom Querschnitt des Materials der Unterlage abhängt. Eine entsprechend dimensionierte Kupfer-Konstantan-Thermosäule besitzt eine um 23% geringere Empfindlichkeit als eine normale Thermosäule der gleichen Materialien und gleicher Gliederzahl; ihre Linearität wird durch dieses Verfahren verbessert.
Mit 2 Textabbildungen 相似文献
Summary The possibility is shown to produce a thermopile by electroplating, the sensitivity of which is independent from the reference temperature. In this case the deposition must have a fixed thickness depending upon the cross section of the base wire. A copper-constantan-thermopile made in this way has a sensitivity being 23 per cent smaller than that of a normal thermopile of the same materials and with the same number of junctions; its linearity is improved by this process.
Résumé On montre qu'il est possible de construire une pile thermoélectrique par galvanoplastie dont la sensibilité est indépendante de la température de référence. Le dépôt galvanique doit avoir une certaine épaisseur en rapport avec la section du noyau. Une pile cuivre-constantan de cette nature a une sensibilité de 23% plus faible qu'une pile normale de même composition et du même nombre de soudures; le processus de fabrication indiqué rend plus linéaires ses indications.
Mit 2 Textabbildungen 相似文献
732.
P. Wilh Werner Dr.-Techn. h. c. 《Pure and Applied Geophysics》1953,25(1):37-43
Summary The present paper deals with certain problems of non-artesian aquifers, with special reference to non-steady flow due to replenishment from the ground surface. Solutions are obtained by direct integration ofBoussinesq's differential equation (transformed), taking also the inclination of the groundwater surface and the slope of the bottom of the aquifer into account. — The study has some bearing on hydrological investigations. For example, it may be desired to find the location of a moving groundwater divide between two water courses, or to determine the quantity of groundwater passing between them. Problems of this nature are also often met with in water supply (artificial infiltration, etc.) and other fields of engineering practice. 相似文献
733.
P. Wilh Werner 《Pure and Applied Geophysics》1952,22(3-4):166-170
Summary The study deals with expansion waves in fluids, with particular reference to hydrodynamic earthquake effects. The current assumption of steady harmonic motion is compared with the assumption that the motion is discontinuous in the sense that it starts from the initial condition of rest. A numerical example shows that the impulsive start may have a considerable influence on the dynamic water pressure. 相似文献
734.
735.
激光剥蚀-等离子体质谱技术及其在地球化学宇宙化学和环境研究中的应用 总被引:1,自引:0,他引:1
JOCHUM Klaus Peter STOLL Brigitte FRIEDRICH Jon M AMINI Marghaleray BECKER Stefan DüCKING Marc EBEL Denton S ENZWEILER Jacinta 胡明月 KUZMIN Dmitry MERTZ KRAUS Regina MüLLER Werner E G REGNERY Julia SOBOLEV Alexander 王晓红 詹秀春 《岩矿测试》2009,28(1):53-68
激光剥蚀-等离子体质谱(LA-ICPMS)已成为地球化学、宇宙化学和环境研究领域元素和同位素原位分析最重要的技术之一。文章介绍了多种类型的质谱仪及其使用的激光器。用途最广的LA-ICPMS仪器之一是单接收器扇形磁场质谱仪,配有Nd:YAG激光剥蚀系统(激光波长分为193 nm和213 nm两种),MPI Mainz实验室使用的就是这套系统,文章对此作一详细介绍。文中阐述了数据优化技术及其多种校正过程;介绍LA-ICPMS在痕量元素和同位素分析领域的一些应用,包括参考物质的研制,Hawaiian玄武岩、Martian陨石、生物骨针和珊瑚虫中痕量元素分析及熔融包裹体和富钙-铝碳质球粒陨石中的铅和锶同位素测量。 相似文献
736.
M. A. Barstow S. Dreizler J. B. Holberg D. S. Finley K. Werner I. Hubeny E. M. Sion 《Monthly notices of the Royal Astronomical Society》2000,314(1):109-122
We present the first evidence for the direct detection of nickel in the photosphere of the hot DO white dwarf REJ 0503−289. While this element has been seen previously in the atmospheres of hot H-rich white dwarfs, this is one of the first similar discoveries in a He-rich object. Intriguingly, iron, which is observed to be more abundant than Ni in the hot DA stars, is not detected, the upper limit to its abundance (Fe/He=10−6 ) implying an Fe/Ni ratio a factor of 10 lower than seen in the H-rich objects (Ni/He=10−5 for REJ 0503−289). The abundances of nickel and various other elements heavier than He were determined from Goddard High Resolution Spectrograph spectra. We used two completely independent sets of non-local thermodynamic equilibrium model atmospheres, which both provide the same results. This not only reduces the possibility of systematic errors in our analysis, but is also an important consistency check for both model atmosphere codes.
We have also developed a more objective method of determining Teff and log g , from the He lines in the optical spectrum, in the form of a formal fitting of the line profiles to a grid of model spectra, an analogue of the standard procedure utilizing the Balmer lines in DA white dwarfs. This gives the assigned uncertainties in T eff and log g a firm statistical basis and allows us to demonstrate that inclusion of elements heavier than H, He and C in the spectral calculations, exclusively considered in most published optical analyses, yields a systematic downward shift in the measured value of T eff . 相似文献
We have also developed a more objective method of determining T
737.
Brett B. Wallace Mark C. Bailey David P. Hamilton 《Aquatic Sciences - Research Across Boundaries》2000,62(4):320-333
Vertical distributions of the cyanobacterium Microcystis aeruginosa are examined in a shallow lake in relation to mixing and thermal stratification over three days. A model of buoyancy regulation by Microcystis aeruginosa, applicable for turbulent environments, is coupled with a one-dimensional hydrodynamic model. The coupled model is applied to Thomsons Lake in Western Australia to examine the relationship between buoyancy regulation and the daily stratification/destratification cycle. The vertical distribution of Microcystis aeruginosa in Thomsons Lake depends on the carbohydrate ballast dynamics and the colony size. When thermal stratification occurs, all the simulations show a similar general pattern of diurnal vertical migration of the Microcystis aeruginosa colonies. The colonies accumulate at the surface during the night and in the morning the colonies lose buoyancy, which leads to a reduction by ~ \sim 50% in colony concentration in the top 0.2--0.3 m of the water column. Afternoon winds redistribute the population over the entire water column. When the lake is fully mixed, the vertical migration pattern of the Microcystis aeruginosa colonies may be affected, depending on the colony size and the intensity of the mixing. 相似文献
738.
This paper presents the first high resolution temperature data from a small Agrostis magellanica mire on subantarctic Marion Island as part of an ongoing island‐wide monitoring project on subsurface ground temperature variability. Variations in ground temperatures were found to be directly linked to the passage of synoptic scale weather systems that influence thermal characteristics and heat fluxes especially in the upper 30 cm of the mire. Preliminary data published here suggest that shallow temperatures will be most affected by changes in synoptic climate that Marion Island is currently experiencing with an increase in average temperatures and a reduction in temperature variability with depth. This study proposes that to effectively detect the ecosystem responses to climate change in a maritime sub‐Antarctic environment the temporal scale of measurement needs to be at least on a diurnal scale to be effective. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
739.
V. Guineva G. Witt J. Gumbel M. Khaplanov R. Werner J. Hedin S. Neichev B. Kirov L. Bankov P. Gramatikov V. Tashev M. Popov K. Hauglund G. Hansen J. Ilstad H. Wold 《Geomagnetism and Aeronomy》2009,49(8):1292-1295
The resonance transition 2P-2S of the atomic hydrogen (Lyman-alpha emission) is the strongest and most conspicuous feature in the solar EUV spectrum. The Lyman-alpha radiation transfer depends on the resonance scattering from the hydrogen atoms in the atmosphere and on the O2 absorption. Since the Lyman-alpha extinction in the atmosphere is a measure for the column density of the oxygen molecules, the atmospheric O2 density and temperature profiles can be calculated thereof. A detector of solar Lyman-alpha radiation was manufactured in the Stara Zagora Department of the Solar-Terrestrial Influences Laboratory (STIL). Its basic part is an ionization camera, filled in with NO. A 60 V power supply is applied to the chamber. The produced photoelectric current from the sensor is fed to a two-channel amplifier, providing analog signal. The characteristics of the Lyman-alpha detector were studied. It passed successfully all tests and the results showed that the so-designed instrument could be used in rocket experiments to measure the Lymanalpha flux. From the measurements of the detector, the Lyman-alpha vertical profile can be obtained. Programs are created to compute the O2 density, atmospheric power and temperature profiles based on Lymanalpha data. The detector design appertained to ASLAF project (Attenuation of the Solar Lyman-Alpha Flux), a scientific cooperation between STIL—Bul.Acad.Sci., Stara Zagora Department and the Atmospheric Physics Group at the Department of Meteorology (MISU), Stockholm University, Sweden. The joint project was part of the rocket experiment HotPay I, in the ALOMAR eARI Project, EU’s 6th Framework Programme, Andøya Rocket Range, Andenes, Norway. The project is partly financed by the Bulgarian Ministry of Science and Education. 相似文献
740.