1,369 research outputs found

    Physics with Like-Sign Muon Beams

    Get PDF
    We point out that both the specific lepton number content and the high energies potentially attainable with muon-muon colliders make it advisable to consider the technical feasibility of including an option of like-sign incoming beams in the studies towards a proposal to build a muon-muon collider with center-of-mass energies in the TeV region. This capability will add some unique physics capabilities to the project. Special attention will have to be paid to polarization retention for the muons.Comment: 13 pages, uuencoded postscript file, also available from ftp://gluon.hep.physik.uni-muenchen.de/preprints/scipp9534.u

    Practical, reliable and inexpensive assay of lycopene in tomato products based on the combined use of light emitting diode (LED) and the optothermal window

    Get PDF
    Light emitting diode (LED) combined with the concept of optothermal window (OW) is proposed as a new approach (LED-OW) to detect lycopene in a wide range of tomato-based products (tomato juice, tomato ketchup, tomato passata and tomato puree). Phytonutrient lycopene is a dominant antioxidant in these products while beta-carotene is present in significantly lower quantities. Therefore for all practical reasons the interfering effect of beta-carotene at 502 nm analytical wavelength can be neglected. The LED-OW method is low-cost and simple, yet accurate and precise. The major attributes of the new method are its rapid speed of response and the fact that no preparation whatsoever of the sample is needed before the analysis. The lycopene found in tomato products studied here varies from 8 mg/100 g to 60 mg/100 g fresh product. Results obtained by LED-OW method were compared to the outcome of conventional, time consuming spectrophotometric methods and the correlation was very good (R = 0.98). Precision of the LED-OW instrumental setup ranged from 0.5 to 7.4%; the RSD achieved for lycopene-richest samples (= 40 mg/100 g) did not exceed 1.7%. Repeatability of analysis by LED-OW was found to vary between 0.7 and 7.1%

    Eliminating the low-mass axigluon window

    Get PDF
    Using recent collider data, especially on the hadronic width the Z0, we exclude axigluons in the currently allowed low-mass window, namely axigluons in the mass range 50 GeV < M_A < 120 GeV. Combined with hadron collider data from di-jet production, axigluons with masses below roughly 1 TeV are now completely excluded.Comment: 8 pages, no figures, LaTe

    An oak is an oak, or not? Understanding and dealing with confusion and disagreement in biological classification

    Get PDF
    Human interaction with the living world, in science and beyond, always involves classification. While it has been a long-standing scientific goal to produce a single all-purpose taxonomy of life to cater for this need, classificatory practice is often subject to confusion and disagreement, and many philosophers have advocated forms of classificatory pluralism. This entails that multiple classifications should be allowed to coexist, and that whichever classification is best, is context-dependent. In this paper, we discuss some practical consequences of classificatory pluralism, in particular with regard to how one is supposed to find the best classification for a given context. We do so by means of a case study concerning oaks, in particular the pedunculate oak (Quercus robur L.) and the sessile oak (Quercus petraea (Matt.) Liebl.), two important putative species that present several classificatory challenges; and by applying one recent philosophical framework conceptualizing classification, the so-called Grounded Functionality Account (GFA) of (natural) kinds. We show how the GFA elucidates several issues related to oak classification and gives directions to optimize classificatory practices, and discuss some implications for scientific taxonomy

    Analysis of MERCATOR data Part I: variable B stars

    Get PDF
    We re-classified 31 variable B stars which were observed more than 50 times in the Geneva photometric system with the P7 photometer attached to the MERCATOR telescope (La Palma) during its first 3 years of scientific observations. HD89688 is a possible beta Cephei/slowly pulsating B star hybrid and the main mode of the COROT target HD180642 shows non-linear effects. The Maia candidates are re-classified as either ellipsoidal variables or spotted stars. Although the mode identification is still ongoing, all the well-identified modes so far have a degree l = 0, 1 or 2.Comment: 4 pages, 3 figures. To appear in: Proceedings of JENAM 2005 'Distant worlds', Communications in Asteroseismolog

    Thermophysical Characterization of Sorption TCM

    Get PDF
    AbstractThermochemical materials (TCM) are proposed for thermal energy storage as one of the future options to achieve lower energy consumption in buildings and other industrial applications, as well as to store energy from solar energy. In this study, the thermophysical properties of two TCM, CaCl2 and zeolite, are determined with TGA and DSC and samples are cycled 4 times with TGA. Results show that the material with the highest energy density is the salt, CaCl2. Moreover, both materials under study present noble cyclability

    Pyrolysis of organic side stream materials for the production of biochar as an amendment in green roofs: Characterization and field experiments

    Get PDF
    Green roofs offer a solution to worldwide problems in cities like: the urban heat island effect, floods and the loss of rural regions. Nevertheless, the widespread application of green roofs still faces some serious challenges, e.g. an excessive amount of drainage water, an excess of nutrients in this water, and plant mortality in periods of severe drought. Also, the production process of the components of these substrates, such as expanded clay, is not environmentally and energy-friendly. Biochar amendment in green roof substrates can help to overcome these problems because of its valuable properties like a high nutrient content, high waterholding capacity (WHC), low density and its self-sustaining production process. In this research, biochar is produced from six different side streams in a pilot-scale rotating kiln carbonization reactor (kg/hour input). These side streams consists out of: MDF, date palm, coffee skins, tree bark, olive stones and a waste wood mix. The produced biochars are characterized with multiple physico-chemical analyses like biochar yield, elemental composition, surface functional groups, morphology, WHC, cation exchange capacity and polyaromatic hydrocarbons (PAH’s). Furthermore, a techno-economical analysis is performed on the large-scale production of these biochars. Small scale (0,25 m2) and field experiments (2.5 m2) with biochar incorporated in commercially available green roof substrates in the temperate climate of the Netherlands and Belgium examine whether biochar can offer a solution to the described problems. Based on the analyses of the biochar, in particular the PAH’s and elemental composition, and the small scale growth experiments, two different biochars made from the waste wood mix and tree bark in concentrations of 1 and 5 % are selected for the field experiments. Growth of Sedum plants is monitored with digital imaging processing over a period of several months, starting from November 2018. Several chemical and physical parameters are monitored and linked to the properties of the biochar incorporated substrate like pH, conductivity, nutrient leaching and waterholding capacity

    Who violates expectations when? How firms’ growth and dividend reputations affect investors’ reactions to acquisitions

    Get PDF
    Research summary: We investigate the role of a firm’s dividend and growth reputations in shaping investors’ interpretations of acquisitions as a negative or positive expectation violation. While our findings reveal that both an acquiring firm’s dividend and growth reputations trigger positive investor reactions, they also show that investors react negatively to an acquisition of a target firm with a strong growth reputation when the acquiring firm has a strong dividend reputation. We also find that investors are inclined to give managers “the benefit of the doubt” to the extent that an acquiring firm strategically frames an acquisition announcement in such a way that it provides assurance to investors that the acquisition is meant to exceed investors’ expectations about shareholder value creation. Managerial summary: We study why investors respond to some acquisitions positively and others negatively. We find that the way acquiring and target firms have created shareholder value in the past, and the information conveyed in the acquisition announcements are important determinants of investors’ differential reactions to acquisitions. Our findings show that while investors generally react positively to acquisitions by firms known for creating value either through dividends or growth, their reactions become negative when a firm known for value creation through dividends acquires a target known for value creation through growth. We further find that managers can favorably influence investor reactions by making it salient in the acquisition announcement how the acquisition is intended to exceed investors’ value creation expectations from the acquiring firm
    • …
    corecore