Application of impedance spectroscopy and conductometry for assessment of varietal differences in wheat

The potentials of an electrochemical and a physical technique for detection of physiological differences in three wheat cultivars under optimal growth conditions were outlined in the study. Electrolyte leakage kinetics was established by continuous measurements of conductivity of solutions in which leaf pieces were incubated for 24 hours. Impedance spectra were obtained from intact leaves at frequency range from 7 to 2010 Hz and 250 mV measuring voltage applied between two gold plated silicon substrates serving as electrodes. The obtained spectra were approximated by a model employing two ARC elements connected in series. Parameters of the previously described diffusion model based on time course conductivity measurements were inversely correlated with electrical impedance spectroscopy data, thus the genotype with highest ion leakage (cultivar Prelom) exhibited lowest impedance magnitude. It was concluded that the two methods were able not merely to distinguish the three studied cultivars but also to rank them in the same order based on their electrical properties

Effectiveness of introduction of solar

The paper considers the problem of saving energy resources through the use of solar collectors for heating water in the pool. The calculated energy savings and costs associated with installation of solar collectors and their service.В работе рассмотрена проблема экономии энергетических ресурсов, посредством использования солнечных коллекторов для подогрева воды в бассейне. Рассчитано количество сэкономленной энергии и затраты связанные с установкой солнечных коллекторов и их обслуживанием

Restoring the valence-shell stabilization in Nd-140

A projectile Coulomb-excitation experiment was performed at the radioactive-ion beam facility HIE-ISOLDE at CERN to obtain E2 and M1 transition matrix elements of Nd-140 using the multistep Coulomb-excitation code GOSIA. The absolute M1 strengths, B(M1; 2(2)(-) -> 2(1)(+)) = 0.033(8)mu(2)(N), B(M1 ; 2(3)(+) -> 2(1)(+)) = 0.26(-0.10)(+0.11)mu(2)(N), and B(M1; 2(4)+ -> 2(1)(+)) <0.04 mu(2)(N) identify the 2(3)(+) state as the main fragment of the one-quadrupole-phonon proton-neutron mixed-symmetry state of Nd-140. The degree of F-spin mixing in Nd-140 was quantified with the determination of the mixing matrix element VF-mix <7(-7)(-13) keV.Peer reviewe

Direct measurement of the intrinsic electric dipole moment in pear-shaped thorium-228

Atomic nuclei with certain combinations of proton and neutron numbers can adopt reflection-asymmetric or octupole-deformed shapes at low excitation energy. These nuclei present a promising avenue in the search for a permanent atomic electric dipole moment—the existence of which has implications for physics beyond the Standard Model of particle physics. Theoretical studies have suggested that certain thorium isotopes may have large octupole deformation. However, due to experimental challenges, the extent of the octupole collectivity in the low-energy states in these thorium nuclei has not yet been demonstrated. Here, we report measurements of the lifetimes of low-energy states in 228Th (Z = 90) with a direct electronic fast-timing technique, the mirror symmetric centroid difference method. From lifetime measurements of the low-lying Jπ = 1− and Jπ = 3− states, the E1 transition probability rates and the intrinsic dipole moment are determined. The results are in agreement with those of previous theoretical calculations, allowing us to estimate the extent of the octupole deformation of 228Th. This study indicates that the nuclei 229Th and 229Pa (Z = 91) may be good candidates for the search for a permanent atomic electric dipole moment

Low collectivity of the 2(1)(+) state of Po-212

International audienceThe lifetime of the $2^+_1$ state of $^{212}$Po was measured in the $^{208}$Pb($^{12}$C,$^{8}$Be)$^{212}$Po transfer reaction by γ -ray spectroscopy employing the recoil distance Doppler shift (RDDS) method. The derived absolute B(E2) value of 2.6(3)W.u. indicates a low collectivity and contradicts previous claims of α-cluster components in the structure of the $2^+_1$ state. It is demonstrated that a consistent description of the properties of the $2^+_1$−$4^+_1$−$6^+_1$−$8^+_1$ sequence in $^{212}$Po cannot be achieved in the framework of a single-j shell-model calculation, either. This puzzle is traced to the properties of the seniority-2 configurations in $^{210}$Pb and $^{210}$Po

Search formixed-symmetry states of nuclei in the vicinity of the double-magic nucleus 208Pb

In this work we present the results from two experiments dedicated to search for quadrupolecollective isovector valence-shell excitation, the states with so-called mixed proton-neutron symmetry (MSS), in nuclei around the doubly magic nucleus 208Pb. 212Po was studied in an α-transfer reaction. 204Hg was studied in an inverse kinematics Coulomb excitation reaction on a carbon target. Both experiments provide indications for existence of one-phonon MSSs. Those are the first experimentally identified MSSs in the mass A ≈ 208 region

Lifetime measurements of the low-lying excited states of ²⁰⁸Po

In this study we present the preliminary results about the lifetimes of the 2₂⁺, 4₁⁺ states of ²⁰⁸Po and the upper limit of the lifetime of the 2₁⁺ state. For measuring the lifetimes of the 2₁⁺ and 4₁⁺ states the Recoil Distance Doppler Shift (RDDS) method and for the lifetime of the 2₂⁺ state the Doppler Shift Attenuation method (DSAM) were used. The resulting absolute transition strength B(M1 ; 2₂⁺ → 2₁⁺) ≥ 0.122(20) μN² reveals the predominant isovector nature of the 2₂⁺ state of ²⁰⁸Po

Low collectivity of the first 2⁺ states of ²¹²,²¹⁰Po

The lifetimes of the first 2⁺ excited states of ²¹²,²¹⁰Po were measured in two transfer reactions ²⁰⁸Pb(¹²C,⁸Be)²¹²Po and ²⁰⁸Pb(¹²C,¹⁰Be)²¹⁰Po by the Recoil Distance Doppler Shift (RDDS) method and by the Doppler Shift Attenuation method (DSAM), respectively. The derived absolute B(E2) values of 2.6(3) W.u. for ²¹²Po and 1.83(28) W.u. for ²¹⁰Po indicate low collectivity. It is shown that the properties of the yrast 2₁⁺, 4₁⁺, 6₁⁺ and 8₁⁺ states in both nuclei cannot be described consistently in the framework of nuclear shell models. It is also demonstrated in the case of ²¹⁰Po that Quasi-particle Phonon Model (QPM) calculations cannot overcome this problem thus indicating the existence of a peculiarity which is neglected in both theoretical approaches