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We studied InAlBiAs thin films of less than 300 nm on the InP substrate with Bi composition up to 3.2%. The samples were grown by molecular beam epitaxy at low growth temperature and were shown to be fully strained to the substrate and have smooth interfaces. A bandgap reduction around 47 meV/%Bi was observed via spectroscopic ellipsometry. The valence band anticrossing model was used to fit the experimental data. The bandgaps of InAlBiAs with more than 3% Bi are much lower than the expected values from the model, which could be the result of alloy disorders. [ABSTRACT FROM AUTHOR]

Using first‐principles electronic structure calculations, it is shown that ferromagnetic Heusler compounds Co2MnX (X = Si, Ge, Sn) present nontrivial topological characteristics and belong to the category of Weyl semimetals. These materials exhibit two topologically interesting band crossings near the Fermi level. These band crossings have complex 3D geometries in the Brillouin zone and are characterized by nontrivial topology as Hopf links and chain‐like nodal lines that are protected by the perpendicular mirror planes. The spin–orbit interaction split these nodal lines into several 0D Weyl band crossings. Unlike previously known topologically nontrivial Heusler materials, these majority spin band crossings lie in or very near to the bandgap of minority spin bands, potentially facilitating experimental observation. [ABSTRACT FROM AUTHOR]

The frequent occurrence of sudden water pollution accidents brings enormous risks to water environment safety. Therefore, there is great need for the modeling and development of early warning systems and rapid response procedures for current water pollution situation in China. This paper proposes an emergency response system based on the integration of Geographic Information System (GIS) technology and a hydraulic/water-quality model. Using the spatial analysis and three-dimensional visualization capabilities of GIS technology, we calculated pollutant diffusion measures, and visualized and analyzed the simulation results, in order to provide the services of early warning and emergency response for sudden water pollution accidents in the Xiangjia Dam area on the Yangtze River. The results show that the proposed system offers reliable technological support for emergency response to sudden water pollution events, and it shows good potential for wide applications in various aspects of water resources protection. [ABSTRACT FROM AUTHOR]

Spatial–temporal rainfall assessments are integral to climate/hydrological modeling, agricultural studies, and water resource planning and management. Herein, we evaluate spatial–temporal rainfall trends and patterns in Pakistan for 1961–2020 using nationwide data from 82 rainfall stations. To assess optimal spatial distribution and rainfall characterization, twenty-seven interpolation techniques from geo-statistical and deterministic categories were systematically compared, revealing that the empirical Bayesian kriging regression prediction (EBKRP) technique was best. Hence, EBKRP was used to produce and utilize the first normal annual rainfall map of Pakistan for evaluating spatial rainfall patterns. While the largest under-prediction was estimated for Hunza (− 51%), the highest and lowest rainfalls were estimated for Malam Jaba in Khyber Pakhtunkhwa province (~ 1700 mm), and Nok-kundi in Balochistan province (~ 50 mm), respectively. A gradual south-to-north increase in rainfall was spatially evident with an areal average of 455 mm, while long-term temporal rainfall evaluation showed a statistically significant (p = 0.05) downward trend for Sindh province. Additionally, downward inter-decadal regime shifts were detected for the Punjab and Sindh provinces (90% confidence). These results are expected to help inform environmental planning in Pakistan; moreover, the rainfall data produced using the optimal method has further implications in several aforementioned fields. [ABSTRACT FROM AUTHOR]

In this study, we evaluated the effectiveness of photochemical reflectance index (PRI) and non-photochemical quenching (NPQ) for assessing water stress in maize for the purpose of developing remote sensing techniques for monitoring water deficits in crops. Leaf-level chlorophyll fluorescence and canopy-level PRI were measured concurrently over a maize field with five different irrigation treatments, ranging from 20% to 90% of the field capacity (FC). Significant correlations were found between leaf-level NPQ (NPQleaf) and the ratio of chlorophyll to carotenoid content (Chl/Car) (R² = 0.71, p < 0.01) and between NPQleaf and the actual photochemical efficiency of photosystem II (ΔF/Fm') (R² = 0.81, p < 0.005). At the early growing stage, both canopy-level PRI and NPQleaf are good indicators of water stress (R² = 0.65 and p < 0.05; R² = 0.63 and p < 0.05, respectively). For assessment of extreme water stress on plant growth, a relationship is also established between the quantum yield of photochemistry in PSII (ΦP) and the quantum yield of fluorescence (ΦF) as determined from photochemical quenching (PQ) and non-photochemical quenching (NPQleaf) of excitation energy at different water stress levels. These results would be helpful in monitoring soil water stress on crops at large scales using remote sensing techniques. [ABSTRACT FROM AUTHOR]

The distribution of many geographical objects and events is affected by the road network; thus, network-constrained point pattern analysis methods are helpful to understand their space structures and distribution patterns. In this study, network kernel density estimation and network K-function are used to study retail service hot-spot areas and the spatial clustering patterns of a local retail giant (Suguo), respectively, in Nanjing city. Stores and roads are categorized to investigate the influence of weighting different categories of point events and network on the analysis. In addition, the competitive relation between Suguo and foreign-brand retail chains was revealed. The comprehensive analysis results derived from the combination of the first-order and second-order properties can be further used to examine the reasonability of the existing store distribution and optimize the locational choice of new stores. [ABSTRACT FROM AUTHOR]