Mechanisms for Translocation of Heavy Metals from Soil to Epigeal Mosses

The mechanisms for translocation of heavy metals from soil to epigeal mosses were investigated. The first mechanism was demonstrated for 137Cs and involved the uplifting of the pollutant-containing dust from the soil, followed by the local secondary deposition on surfaces of epigeal mosses and epiphytic lichens. The second mechanism involved the diffusion of metal cations from the soil through water wetting the moss into the gametophyte. The mechanism was demonstrated by measuring the electric conductance of wetted gametophytes with single ends immersed in solutions of Cu and Na salts. In addition, the concentrations of Cu and Cd were compared in moss samples exposed to the natural soil and to the soil contaminated with the metals. The exposition to the contaminated soil resulted in the statistically significant increase of metal concentrations in the gametophytes

Structural properties of cyclic polyelectrolytes in dilute good solvent

Cyclic polymers display unique physical behaviors in comparison to their linear counterparts. Theoretical, computational and experimental studies have revealed that some of their distinctive properties are also observed in charged variants of cyclic polymers, known as cyclic polyelectrolytes (PEs), especially in terms of their structural responses to variations in the strength of electrostatic interactions. In this study, we investigate the impact of cyclic topology on the conformations of PE chains in dilute good solvent using scaling analysis and coarse-grained bead-spring molecular dynamics simulations. Our observations indicate that, in contrast to linear PE chains, cyclic topology results in more compact conformations at low and intermediate Bjerrum lengths. Moreover, two structural metrics, asphericity and prolateness, which quantify deviations from spherical and flat molecular shapes, exhibit non-monotonic behaviors for cyclic PEs. This stands in contrast to linear PEs, where these shape characteristics exhibit a monotonic trend with increasing Bjerrum length. A feasible analytical theory, developed to account for ionic distributions around cyclic PE chains, suggests that the fundamental difference between linear and cyclic chain conformations may be attributed to topological effects influencing long-range electrostatic interactions

Study of three-nucleon dynamics in the dp breakup collisions using the Wasa detector

An experiment to investigate the ^{1}H(d,pp)n breakup reaction using a deuteron beam of 300, 340, 380 and 400 MeV and the WASA detector has been performed at the Cooler Synchrotron COSY-Jülich. As a first step, the data collected at the beam energy of 340 MeV are analysed, with a focus on the proton–proton coincidences registered in the Forward Detector. Elastically scattered deuterons are used for precise determination of the luminosity. The main steps of the analysis, including energy calibration, particle identification (PID) and efficiency studies, and their impact on the final accuracy of the result, are discussed

Study of three-nucleon dynamics in the dp breakup collisions using the Wasa detector

An experiment to investigate the ^{1}H(d,pp)n breakup reaction using a deuteron beam of 300, 340, 380 and 400 MeV and the WASA detector has been performed at the Cooler Synchrotron COSY-Jülich. As a first step, the data collected at the beam energy of 340 MeV are analysed, with a focus on the proton–proton coincidences registered in the Forward Detector. Elastically scattered deuterons are used for precise determination of the luminosity. The main steps of the analysis, including energy calibration, particle identification (PID) and efficiency studies, and their impact on the final accuracy of the result, are discussed

Measurement of differential cross sections for the deuteron-proton breakup reaction at 160 MeV

W. Parol, A. Kozela, K. Bodek, A. Deltuva, M. Eslami-Kalantari, J. Golak, N. Kalantar-Nayestanaki, G. Khatri, St. Kistryn, J. Kubo´s, P. Kulessa, A. Magiera, H. Mardanpour, J. G. Messchendorp, I. Mazumdar, R. Skibiński, I. Skwira-Chalot, A. Ramazani-Moghaddam-Arani, D. Rozpędzik, H. Witała, B. Włoch, A. WrońskaDifferential cross sections for the deuteron breakup 1H(d, pp)n reaction were measured for a large set of 243 geometrical configurations at the beam energy of 80 MeV/nucleon. The cross-section data are normalized by the luminosity factor obtained on the basis of a simultaneous measurement of the elastic-scattering channel and the existing cross-section data for this process. The results are compared with the theoretical calculations modeling nuclear interactions with and without taking into account the three-nucleon force (3NF) and the Coulomb interaction. In the validated region of the phase space, both the Coulomb force and 3NF play an important role in providing a good description of the data. There are also regions in which description improvements due to the inclusion of 3NF are insufficient

Few-nucleon system dynamics studied via deuteron-deuteron collisions at 160 MeV

Pozostali autory: I. Ciepał, K. Bodek, N. Kalantar-Nayestanaki, G. Khatri, St. Kistryn, A. Kozela, J. Kubo´s, P. Kulessa, A. Magiera, J. Messchendorp, I. Mazumdar, W. Parol, R. Ramazani-Sharifabadi, D. Rozpedzik, I. Skwira-Chalot, B. Włoch, A. Wrońska, J. ZejmaFour nucleon scattering at intermediate energies provides unique opportunities to study effects of the two key ingredients of the nuclear dynamics, the nucleon-nucleon P-wave (NNP-wave) and the three-nucleon force (3NF). This is possible only with systematic and precise data, in conjunction with exact theoretical calculations. Using the BINA detector at KVI Groningen, the Netherlands, a rich set of differential cross section of the 2H(d, dp)n breakup reaction at 160 MeV deuteron beam energy has been measured. Besides the three-body breakup, also cross sections of the 2H(d, 3He)n proton transfer reaction have been obtained. The data are compared to the recent calculations for the threecluster breakup

Determination of phase space region for cross-check validation of the neutron detection in the BINA experiments

cd autorów: B. Włoch, K. Bodek, I Ciepał, M. Eslami-Kalantari, J. Golak, N. Kalantar-Nayestanaki, G. Khatri, St. Kistryn, A. Kozela, J. Kuboś, P. Kulessa, A. Magiera, H. Mardanpour, J. Messchendorp, I. Mazumdar, W. Parol, A. Ramazani-Moghaddam-Arani, D. Rozpędzik, R. Skibiński, I. Skwira-Chalot, H. Witała, A Wrońska, J. ZejmaDeuteron breakup reactions are basic laboratories for testing nuclear force models. Recent improvements in the data analysis allow for direct identification of neutrons in the BINA detection setup. This opens up the opportunity to study new aspects of few-nucleon system dynamics like charge dependence of nuclear force or Coulomb interaction. In this paper we determine regions along the kinematical curves where differential cross section of deuteron-proton breakup reactions can be measured by the proton-neutron and proton-proton coincidences simultaneously. This is particularly useful for validation of the neutron detection technique

High tolerance of a high-arctic willow and graminoid to simulated ice encasement

Source at http://www.borenv.net/BER/ber231-6.htm.Climate change-induced snow thaw and subsequent accumulation of ice on the ground is a potential, major threat to snow-dominated ecosystems. While impacts of ground-ice on arctic wildlife are well explored, the impacts on tundra vegetation is far from understood. We therefore tested the vulnerability of two high-arctic plants, the prostrate shrub Salix polaris and the graminoid Luzula confusa, to ice encasement for 60 days under full environmental control. Both species were tolerant, showing only minor negative responses to the treatment. Subsequent exposure to simulated late spring frost increased the amount of damaged tissue, particularly in S. polaris, compared to the pre-frost situation. Wilting shoot tips of S. polaris increased nearly tenfold, while the proportion of wilted leaves of L. confusa increased by 15%. During recovery, damaged plants of S. polaris responded by extensive compensatory growth of new leaves that were much smaller than leaves of non-damaged shoots. The results suggest that S. polaris and L. confusa are rather tolerant to arctic winter-spring climate change, and this may be part of the reason for their wide distribution range and abundance in the Arctic

Current stage of studies of the star configurations at intermediate energies with the use of the BINA detector

cd autorów: Kazimierz Bodek, Izabela Ciepał, Mohammad Eslami-Kalantari, Nasser Kalantar-Nayestanaki, Ghanshyambhai Khatri, Stanisław Kistryn, Adam Kozela, Joanna Kuboś, Paweł Kulessa, Andrzej Magiera, Hossein Mardanpour, Johan Messchendorp, Indranil Mazumdar, Wiktor Parol, Ahmad Ramazani-Moghaddam-Arani, Dagmara Rozpędzik, Izabela Skwira-Chalot, Bogusław Włoch, Aleksandra Wrońska, Jacek ZejmaThe Space Star Anomaly in proton-deuteron breakup cross-section occurs at energies of about 10 MeV. Data for higher energies are sparse. Therefore, a systematic scan over star configurations in the range of intermediate energies between 50 and 100 MeV/nucleon is carried out on the basis of data collected with the large acceptance BINA detector. The preliminary cross section results for forward star configurations at 80 MeV/nucleon slightly surpass the theoretical calculations, but the systematic uncertainties are still under study. Also, a new variable describing rotation of star configurations is proposed