Phosphorus Behaviour and Its Basic Indices under Organic Matter Transformation in Variable Moisture Conditions: A Case Study of Fen Organic Soils in the Odra River Valley, Poland

Lowering of groundwater levels caused by anthropogenic changes in the environment gives rise to global problems, most of which relate to soil degradation such as land desertification or organic soil degradation. The transformation of drainage-sensitive organic soils causes many irreversible changes during organic matter (OM) transformation. Phosphorous (P) behaviour is one of the aspects of OM transformation that requires further investigation, due to the P transformations’ complex dependency on many environmental factors. Our study aimed to characterise behaviour of P and find indices reflecting P changes under the influence of OM transformation in drained organic soils in the Odra river valley. The studies were carried out on soils representing different stages of soil degradation in which basic soil properties, including different P forms, were determined with commonly used methods. The results showed significantly higher content of soluble P forms (Pw, PCaCl2, PM3), particularly in the most drained postmurshic soil (P1). The indices used in this study—Ip, PSD, C:Pt, N:Pt—reflected well the P and OM transformations in organic soils degraded by drainage. This was indicated by numerous statistically significant relationships between the indices and basic soil properties (e.g., Ash, C, N), as well as different P forms (Pt, Pmin, Pox, Porg, Pw, PCaCl2, PM3). The PSD and Ip values increased and the C:Pt and N:Pt ratios decreased with the degree of OM mineralisation and the degree of site drainage (P3 < P2 < P1).

Quantum field theory of space-like neutrino

We performed a Lorentz covariant quantization of the spin-1/2 fermion field assuming the space-like energy-momentum dispersion relation. We achieved the task in the following steps: (i) determining the unitary realizations of the inhomogenous Lorentz group in the preferred frame scenario by means of the Wigner–Mackey induction procedure and constructing the Fock space; (ii) formulating the theory in a manifestly covariant way by constructing the field amplitudes according to the Weinberg method; (iii) obtaining the final constraints on the amplitudes by postulating a Dirac-like free field equation. Our theory allows to predict all chiral properties of the neutrinos, preserving the Standard Model dynamics. We discussed the form of the fundamental observables, energy and helicity, and show that non-observation of the $$+\tfrac{1}{2}$$ + 1 2 helicity state of the neutrino and the $$-\tfrac{1}{2}$$ - 1 2 helicity state of the antineutrino could be a direct consequence of the “tachyoneity” of neutrinos at the free level. We found that the free field theory of the space-like neutrino is not invariant under the C and P transformations separately but is CP-invariant. We calculated and analyzed the electron energy spectrum in tritium decay within the framework of our theory and found an excellent agreement with the recent measurement of KATRIN. In our formalism the questions of negative/imaginary energies and the causality problem does not appear.

Approximate Lyapunov-perron Transformations: Computation and Applications to Quasi-periodic Systems

A new technique for the analysis of dynamical equations with quasi-periodic coefficients (so-called quasi-periodic systems) is presented. The technique utilizes Lyapunov-Perron (L-P) transformation to reduce the linear part of a quasi-periodic system into the time-invariant form. A general approach for the construction of L-P transformations in the approximate form is suggested. First, the linear part of a quasi-periodic system is replaced by a periodic system with a 'suitable' large principal period. Then, the state transition matrix of the periodic system is computed in the symbolic form using Floquet theory. Finally, Lyapunov-Floquet theorem is used to compute approximate L-P transformations. A two-frequency quasi-periodic system is studied and transformations are generated for stable, unstable and critical cases. The effectiveness of these transformations is demonstrated by investigating three distinct quasi-periodic systems. They are applied to a forced quasi-periodic Hill equation to generate analytical solutions. It is found that the closeness of the analytical solutions to the exact solutions depends on the principal period of the periodic system. A general approach to obtain the stability bounds on linear quasi-periodic systems with stochastic perturbations is also discussed. Finally, the usefulness of approximate L-P transformations to nonlinear quasi-periodic systems is presented by analyzing a quasi-periodic Hill equation with cubic nonlinearity using time-dependent normal form theory. The closed-form solution generated is found to be in good agreement with the exact solution.

Acid-catalyzed transformation of cassane diterpenoids from Caesalpinia bonduc to aromatic derivatives

Transformations of cassane diterpenoids from Caesalpinia bonduc into aromatic derivatives, either in CDCl3 or in CHCl3 irradiated with UV light or catalyzed by AlCl3, were described.

On Computation of Approximate Lyapunov-Perron Transformations

Many dynamical systems can be modeled by a set of linear/nonlinear ordinary differential equations with quasi-periodic coefficients. Application of Lyapunov-Perron (L-P) transformations to such systems produce dynamically equivalent systems in which the linear parts are time-invariant. In this work, a technique for the computation of approximate L-P transformations is suggested. First, a quasi-periodic system is replaced by a periodic system with a ‘suitable’ large principal period to which Floquet theory can be applied. Then, the state transition matrix (STM) of the periodic system is computed in the symbolic form using shifted Chebyshev polynomials and Picard iteration method. Finally, since the STM can be expressed in terms of a periodic matrix and a time-invariant matrix (Lyapunov-Floquet theorem), this factorization is utilized to compute approximate L-P transformations. A two-frequency quasi-periodic system is investigated using the proposed method and approximate L-P transformations are generated for stable, unstable and critical cases. These transformations are also inverted by defining the adjoint system to the periodic system. Unlike perturbation and averaging, the proposed technique is not restricted by the existence of a generating solution and a small parameter. Approximate L-P transformations can be utilized to design controllers using time-invariant methods and may also serve as a powerful tool in bifurcation studies of nonlinear quasi-periodic systems.

Just Transformations to Sustainability

Transformations towards sustainability are needed to address many of the earth’s profound environmental and social challenges. Yet, actions taken to deliberately shift social–ecological systems towards more sustainable trajectories can have substantial social impacts and exclude people from decision-making processes. The concept of just transformations makes explicit a need to consider social justice in the process of shifting towards sustainability. In this paper, we draw on the transformations, just transitions, and social justice literature to advance a pragmatic framing of just transformations that includes recognitional, procedural and distributional considerations. Decision-making processes to guide just transformations need to consider these three factors before, during and after the transformation period. We offer practical and methodological guidance to help navigate just transformations in environmental management and sustainability policies and practice. The framing of just transformations put forward here might be used to inform decision making in numerous marine and terrestrial ecosystems, in rural and urban environments, and at various scales from local to global. We argue that sustainability transformations cannot be considered a success unless social justice is a central concern.

The role of concentrations gradients on phosphorus and iron dynamics from chemically-dosed horizontal flow wetlands for tertiary sewage treatment

This study examined the dynamics of iron (Fe) and phosphorus (P) transformations from the surface sludge accumulated in tertiary horizontal flow (HF) treatment wetlands (TW) chemically dosed for P removal. Site surveys showed P was stored in HF TW with and without artificial aeration on average, with instances of P release in the non-aerated site. Controlled experiments revealed storing TW surface sludge for over 24 hours resulted in limited oxygen and nitrate concentrations, resulting in both P and Fe release. The rate of P release increased with increasing water-sludge P concentration gradients, and the reaction could take as little as 10 minutes. Convection had no impact on P transformation rates. The findings suggest mitigation strategies could include the manipulation of the biogeochemical environment by managing oxygen and nitrate concentrations within the wetlands. A better understanding of links between Fe, P, and nitrate is needed to test proactive mitigation strategies for small wastewater treatment plants.

Transformations of FCC catalysts and carbonaceous deposits during repeated reaction-regeneration cycles

Transformations of an industrial zeolite-based fluid catalytic cracking (FCC) catalyst and its coke deposits during regeneration following FCC reactions of a representative refinery stream are investigated.

Enhanced toxicity of environmentally transformed ZnO nanoparticles relative to Zn ions in the epibenthic amphipod Hyalella azteca

Transformations of ZnO NPs under different environmental conditions alters their toxicity to sediment-dwelling crustaceans.