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The Chinese Loess Plateau (CLP) plays a vital role as an ecological barrier in maintaining the hydrological and climatic conditions of the Yellow River Basin, preventing desertification, and preserving biodiversity. Conducting a systematic analysis and assessment of the saturated hydrological conductivity (Ksat) on the Loess Plateau is crucial for modeling and simulating processes like surface runoff and solute migration. However, due to the uncertainty in detecting the saturated hydraulic conductivity, there are very few regional spatial analyses of the saturated hydraulic conductivity of the CLP. The research results show that the Campbell model is more suitable for the CLP than others. Spatially, Ksat gradually decreases from northwest to southeast. The Ksat in the surface layer (0 cm) was significantly larger than that at the lower soil depths, and the Ksat variability of each soil layer was moderate. Moran;s I decreased as the lag distance increased; this indicated a positive spatial correlation between Ksat and the correlation gradually decreasing with distance. The scattered points are mainly located in the first quadrant, so the local spatial auto-correlation characteristics of the Ksat in this area are clustered with high values. The Ksat for different land cover on the CLP increases in the order grassland > forest land > agricultural land and increases with elevation. This study improves our understanding of land resources and ecological environment management in the CLP. [ABSTRACT FROM AUTHOR]

We prove the existence of a triple , where is a class of finite groups consisting of groups of odd order which is complete (i.e., closed under subgroups, homomorphic images, and extensions), is a finite simple group, is an -maximal subgroup in , and is not pronormal in . [ABSTRACT FROM AUTHOR]

Nonlinear interactions of spin-waves and their quanta, magnons, have emerged as prominent candidates for interference-based technology, ranging from quantum transduction to antiferromagnetic spintronics. Yet magnon multiplication in the terahertz (THz) spectral region represents a major challenge. Intense, resonant magnetic fields from THz pulse-pairs with controllable phases and amplitudes enable high order THz magnon multiplication, distinct from non-resonant nonlinearities such as the high harmonic generation by below-band gap electric fields. Here, we demonstrate exceptionally high-order THz nonlinear magnonics. It manifests as 7th-order spin-wave-mixing and 6th harmonic magnon generation in an antiferromagnetic orthoferrite. We use THz two-dimensional coherent spectroscopy to achieve high-sensitivity detection of nonlinear magnon interactions up to six-magnon quanta in strongly-driven many-magnon correlated states. The high-order magnon multiplication, supported by classical and quantum spin simulations, elucidates the significance of four-fold magnetic anisotropy and Dzyaloshinskii-Moriya symmetry breaking. Moreover, our results shed light on the potential quantum fluctuation properties inherent in nonlinear magnons. The authors demonstrate high-order terahertz nonlinear magnonics using two-dimensional coherent spectroscopy, revealing the emergence of seventh-order spin-wave mixing and sixth harmonic magnon generation within an antiferromagnetic orthoferrite. [ABSTRACT FROM AUTHOR]