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This work investigated the effect of Fe/Mn ratio on the microstructure and mechanical properties of non-equimolar Fe80−xMnxCo10Cr10 (x = 30% and 50%) high-entropy alloys (HEAs) fabricated by laser powder bed fusion (LPBF) additive manufacturing. Process optimization was conducted to achieve fully dense Fe30Mn50Co10Cr10 and Fe50Mn30Co10Cr10 HEAs using a volumetric energy density of 105.82 J·mm−3. The LPBF-printed Fe30Mn50Co10Cr10 HEA exhibited a single face-centered cubic (FCC) phase, while the Fe50Mn30Co10Cr10 HEA featured a hexagonal close-packed (HCP) phase within the FCC matrix. Notably, the fraction of HCP phase in the Fe50Mn30Co10Cr10 HEAs increased from 0.94 to 28.10%, with the deformation strain ranging from 0 to 20%. The single-phase Fe30Mn50Co10Cr10 HEA demonstrated a remarkable combination of high yield strength (580.65 MPa) and elongation (32.5%), which surpassed those achieved in the FeMnCoCr HEA system. Comparatively, the dual-phase Fe50Mn30Co10Cr10 HEA exhibited inferior yield strength (487.60 MPa) and elongation (22.3%). However, it displayed superior ultimate tensile strength (744.90 MPa) compared to that in the Fe30Mn50Co10Cr10 HEA (687.70 MPa). The presence of FCC/HCP interfaces obtained in the Fe50Mn30Co10Cr10 HEA resulted in stress concentration and crack expansion, thereby leading to reduced ductility but enhanced resistance against grain slip deformation. Consequently, these interfaces facilitated an earlier attainment of yield limit point and contributed to increased ultimate tensile strength in the Fe50Mn30Co10Cr10 HEA. These findings provide valuable insights into the microstructure evolution and mechanical behavior of LPBF-printed metastable FeMnCoCr HEAs. [ABSTRACT FROM AUTHOR]

This paper describes the rationale and the protocol of the first component of the third simulation round of the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP3a, http://www.isimip.org , last access: 2 November 2023) and the associated set of climate-related and direct human forcing data (CRF and DHF, respectively). The observation-based climate-related forcings for the first time include high-resolution observational climate forcings derived by orographic downscaling, monthly to hourly coastal water levels, and wind fields associated with historical tropical cyclones. The DHFs include land use patterns, population densities, information about water and agricultural management, and fishing intensities. The ISIMIP3a impact model simulations driven by these observation-based climate-related and direct human forcings are designed to test to what degree the impact models can explain observed changes in natural and human systems. In a second set of ISIMIP3a experiments the participating impact models are forced by the same DHFs but a counterfactual set of atmospheric forcings and coastal water levels where observed trends have been removed. These experiments are designed to allow for the attribution of observed changes in natural, human, and managed systems to climate change, rising CH 4 and CO 2 concentrations, and sea level rise according to the definition of the Working Group II contribution to the IPCC AR6. [ABSTRACT FROM AUTHOR]

Comprehending the correlation between alterations in human‐flood distance and flood fatalities (as well as displacements) is pivotal for formulating effective human adaptive strategies in response to floods. However, this relationship remains inadequately explored in existing global analyses. To address this gap, we examine 910 flood events occurring from 2000 to 2018, resulting in significant numbers of fatalities and displacements. We find that in 53% of countries, humans tend to distance from floods, particularly in the Middle East. Such distancing greatly mitigates flood fatalities and displacements. Simultaneously, in areas with increased flood protection level (FPL), humans are less likely to move away from floods. Furthermore, FPL and human‐flood distance have decreased in regions affected by ice jam‐ and hurricane‐induced floods from 2000 to 2018. Notably, regions with human‐flood distance slightly below the average for a given flood type experience more severe flood fatalities. Plain Language Summary: People have developed effective ways (i.e., distancing from flood and increasing flood protection level) to adapt and minimize the impact of catastrophic floods on exposed populations. However, the relationship between these behaviors and flood fatalities (as well as displacements) is not well understood on a global scale. To address this knowledge gap, we study 910 flood events that occurred between 2000 and 2018, leading to significant fatalities and displacements. We find that in 53% of countries, people tend to move away from flood‐affected areas, especially in the Middle East. This distancing behavior greatly reduces the number of fatalities and displaced individuals caused by floods. Additionally, in areas with higher flood protection level, people are less likely to relocate away from floods. Over the studied period, both flood protection levels and the distance between humans and flood‐prone areas have decreased in regions affected by ice jam‐ and hurricane‐induced floods. Importantly, regions where the distance between humans and floods is slightly below the average for a given flood type experience more severe flood fatalities. These findings could help improve the efficiency of flood control management and the adoption of adaptive policies. Key Points: 53% of countries witnessed humans distancing themselves from floods between 2000 and 2018, especially those in the Middle EastHumans distancing from the floods leads to a substantial reduction in both flood fatalities and flood displaced populationHumans residing in regions with a high flood protection level tend not to move away from the flood [ABSTRACT FROM AUTHOR]

The most basic features of climatological normals and variability are useful for describing observed or likely future climate fluctuations. Pan evaporation (Epan) is an important indicator of climate change; however, current research on Epan has focused on its change in mean rather than its variability. The variability of monthly Epan from 1961 to 2020 at 969 stations in China was analyzed using a theoretical framework that can distinguish changes in Epan variance between space and time. The Epan variance was decomposed into spatial and temporal components, and the temporal component was further decomposed into interannual and intra-annual components. The results show that the variance in Epan was mainly controlled by the temporal component. The time variance was mainly controlled by intra-annual variance, decreasing continuously in the first 30 years, and slightly increasing after the 1990s. This is mainly due to the fact that the decrease of wind speed and the increase of water vapor pressure deficit with the temperature increase offset each other and inhibit the variability of Epan. The variance decreased more in the northern region, whereas it exhibited a small decrease or slight increase in the southern region. The reduction in seasonality was dominated by spring, followed by summer. The differences in Epan variability in space and season were mainly caused by the differing rates of change in evaporation driving forces, such as a greater reduction in wind speed in the northern region and spring. Significance Statement: The purpose of this study is to better understand how the variability of evaporation changes rather than in mean under climate change. This is important because the variability is useful to describe the observed or likely future fluctuations, and a small fluctuation may have large impacts on water practices, such as agricultural production. Our findings showed that the temporal and spatial variability of evaporation decreased due to its drivers offsetting each other. However, because the drivers are numerous and continuously changing under climate change, it is necessary to pay attention to its mean and variability for serving water resources practice. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Mine Automation is the property of Industry & Mine Automation Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper we show existence of positive solutions for a class of problems involving the fractional Laplacian in exterior domain and Choquard type nonlinearity. We prove the main results using variational method combined with Brouwer theory of degree and Deformation Lemma.. [ABSTRACT FROM AUTHOR]

Overlapping surgery or double-booking is a vital yet disputed issue in healthcare field. However, safety of the overlapping surgery during laparoscopic common bile duct exploration (LCBDE) remains unclear. This study aimed to assess the clinical outcomes and safety of overlapping surgery during laparoscopic cholecystectomy and LCBDE for gallbladder and common bile duct stones (CBDS). This study retrospectively reviewed 2736 laparoscopic cholecystectomy and LCBDE surgeries during 2013–2020. One thousand, two hundred eighty patients underwent LCBDE through cystic duct, including 867 receiving overlapping procedures, while 1456 underwent LCBDE through laparoscopic choledochotomy (LC), including 981 who underwent overlapping procedures. Data regarding patient sex, age, body mass index, the American Society of Anesthesiology grade, comorbidities, preoperative liver function test, previous upper abdominal surgery, presence of acute cholecystitis, cholangitis, pancreatitis, or jaundice, common bile duct (CBD) or CBDS diameter, CBDS number, LCBDE operation time, procedure duration, length of stay, stone clearance, CBD closure methods, conversion to open surgery, and complications were collected. Differences in demographics and clinical variables between both groups were not significant, and the unadjusted outcomes were comparable, except for the total procedure duration (transcystic: p <.001; LC: p <.001). After adjusting for demographics and clinical variables, overlapping surgery showed an extended total surgical procedure duration (transcystic: standardized coefficient = 0.084, p =.004; LC: standardized coefficient = 0.072, p =.015). Other effects of overlapping surgery were also comparable. Overlapping surgery in laparoscopic cholecystectomy and LCBDE was safe at our institution. However, the association of patient outcomes with overlapping laparoscopic cholecystectomy and LCBDE should be further investigated. [ABSTRACT FROM AUTHOR]

In this paper we consider the problem (pλ) { −Δu + vλ(x)u = (Ip * |u|2*p)|u|2*μ−2u in RN, u > 0 in RN, where Vλ = λ+V0 with λ ≥ 0, V0 ∈ LN/2(RN), Iμ = 1/|u|μ is the Riesz potential with 0 < μ < min {N,4} and 2*μ = 2N−μ/N−2 with N ≥ 3. Under some smallness assumption on V0 and λ we prove the existence of two positive solutions of (Pλ). In order to prove the main results, we used variational methods combined with degree theory. [ABSTRACT FROM AUTHOR]

Copyright of Hydrogeology & Engineering Geology / Shuiwendizhi Gongchengdizhi is the property of Hydrogeology & Engineering Geology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tropical Geography is the property of Tropical Geography Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We consider in R3 the singularly perturbed Schrödinger-Poisson system {−ε2Δv + V(x)v + ϕ(x)v = ƒ(v), −Δϕ = v2. Using variational techniques, we construct solutions which concentrate around the saddle points of the external potential V, as ε → 0. [ABSTRACT FROM AUTHOR]

Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mountain Research (10082786) is the property of Mountain Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper is dedicated to studying the Choquard equation{−Δu+V(x)u=(Iα∗|u|p)|u|p−2u+g(u),x∈RN,u∈H1(RN),{−Δu+V(x)u=(Iα∗|u|p)|u|p−2u+g(u),x∈RN,u∈H1(RN),where N≥4N≥4, α∈(0,N)α∈(0,N), V∈C(RN,R)V∈C(RN,R) is sign-changing and periodic, IαIα is the Riesz potential, p=N+αN−2p=N+αN−2 and g∈C(R,R)g∈C(R,R). The equation is strongly indefinite, i.e., the operator −Δ+V−Δ+V has infinite-dimensional negative and positive spaces. Moreover, the exponent p=N+αN−2p=N+αN−2 is the upper critical exponent with respect to the Hardy-Littlewood-Sobolev inequality. Under some mild assumptions on gg, we obtain the existence of nontrivial solutions for this equation. [ABSTRACT FROM AUTHOR]

We are concerned with nonlinear fractional Choquard equations involving critical growth in the sense of the Hardy-Littlewood-Sobolev inequality. Without the Ambrosetti-Rabinowitz condition or monotonicity condition on the nonlinearity, we establish the existence of radially symmetric ground state solutions. [ABSTRACT FROM AUTHOR]

The eastern margin of the Tibetan Plateau is characterized by frequent earthquakes; however, research of paleo–earthquakes in the area has been limited, owing to the alpine topography and strong erosion. Detailed investigations of soft–sediment deformation (SSD) structures are valuable for understanding the trigger mechanisms, deformation processes, and the magnitudes of earthquakes that generate such structures, and help us to understand tectonic activity in the region. To assess tectonic activity during the late Quaternary, we studied a well–exposed sequence of Shawan lacustrine sediments, 7.0 m thick, near Lake Diexi in the upper reaches of the Minjiang River. Deformation is recorded by both ductile structures (load casts, flame structures, pseudonodules, ball–and–pillow structures, and liquefied convolute structures) and brittle structures (liquefied breccia, and microfaults). Taking into account the geodynamic setting of the area and its known tectonic activity, these SSD structures can be interpreted in terms of seismic shocks. The types and forms of the structures, the maximum liquefaction distances, and the thicknesses of the horizons with SSD structures in the Shawan section indicate that they record six strong earthquakes of magnitude 6–7 and one with magnitude >7. A recent study showed that the Songpinggou fault is the seismogenic structure of the 1933 Ms7.5 Diexi earthquake. The Shawan section is located close to the junction of the Songpinggou and Minjiang faults, and records seven earthquakes with magnitudes of ∼7. We infer, therefore, that the SSD structures in the Shawan section document deglacial activity along the Songpinggou fault. [ABSTRACT FROM AUTHOR]

The Xining basin is located in the northeastern margin of the Qinghai‐Tibet Plateau. It is a rift basin formed in Mesozoic and Cenozoic and structurally belongs to the intersection of Kunlun and Qilian Mountains. Cenozoic fluvial and lacustrine sedimentary strata are continuous in the Xining basin, with a thickness of more than 800 m, completely recording the deformation uplifting, weathering and denudation history and climate change process of the northeastern plateau. Currently, early Miocene Xijia fauna, early Middle Miocene Danshuilu fauna and late Middle Miocene Diaogou fauna are discovered in the Xining basin, which provide an important basis for the stratigraphic correlation of the Cenozoic strata in the Xining basin. However, in the next few decades, there are no reports about the large mammal fossils in the Xining basin, especially about late Miocene fauna. The author discovered a large amount of mammal fossils in the Neogene sedimentary strata in Huzhu area, Xining basin. According to the identification results of the Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, these fossils mainly included Hipparion dongxiangense, Chilotherium sp., Parelasmotherium sp., Stephanocemas sp. and Kubanochoerus sp. and their age was early Late Miocene. Since the discovery of this set of fossils directly filled the blank that there were no large mammal fossils in the Xining basin in Late Miocene, it was very important for studying the magnetic stratigraphic chronology of fossil‐forming strata and establishing the paleomagnetic chronology scale plate of mammal fossils. In this paper, the paleomagnetic data of the fossil‐forming stratigraphic profile, Banyan profile, were measured and the paleomagnetic records were collected through high density sampling, and finally the paleomagnetic polarity column of the profile was established. The results showed that five positive and five negative polarity segments were recorded in Banyan profile, which corresponded well to the polarity between C3Br.1n‐C4n.2n in the standard polarity column. The age of profile top was about 7.25 Ma and profile bottom was about 8.4 Ma, with an age range of 1.15 Ma. The mammal fossils discovered this time were exposed between positive and negative polarities N5 and R5 at the bottom of the profile, corresponding to C4r.1r at negative polarity and C4n.2n at positive polarity in the standard polarity column. The age of mammal fossils was about 8.3 Ma. The paleomagnetic chronology of the strata and paleontological fossils determined the absolute age of late Miocene mammal fossils and expanded the upper age of late Miocene Xianshuihe Formation (N1xn) in the Xining basin, which had provided new basic data for further studying the stratigraphic deposition and correlation of late Cenozoic strata and regional environmental evolution. [ABSTRACT FROM AUTHOR]

Precipitation extremes are expected to increase by 7% per degree of warming according to the Clausius–Clapeyron (CC) relation. However, this scaling behavior is inappropriate for high temperatures and short-duration precipitation extremes. Here, daily data from 702 stations during 1951–2014 and hourly data from 8 stations during 2000–15 are used to examine and explain this behavior in China. Both daily and hourly precipitation extremes exhibit an increase in temperature dependency at lower temperatures. The CC scaling transitions from positive to negative rates with temperatures greater than 25°C. Unlike the increase in daily data, which is similar to single-CC (1CC) scaling, the increase in hourly data resembles super-CC (2CC) scaling for temperatures greater than 13°C. Results show that the precipitation extremes are controlled by water vapor for a given temperature. At lower temperatures, precipitation extremes exhibit a positive linear dependence on daily actual vapor pressure whose value is almost equal to the saturated vapor pressure at a given temperature. At higher temperatures, actual vapor pressure has difficulty maintaining a consistent increasing rate because of the exponential increasing of the saturated vapor pressure. Higher temperatures result in larger vapor pressure deficits, which lead to sharp decreases in precipitation extremes. Similar scaling behaviors are obtained in 10 river basins over China, where the breaking point temperature increases from 17°C along the northwest inland area to 25°C along the southeast coast. These behaviors demonstrate that precipitation extremes are firmly linked to temperature when there is sufficient moisture at lower temperatures and limited by insufficient moisture at higher temperatures. Overall, precipitation extreme events require more attention in a warming climate. [ABSTRACT FROM AUTHOR]

The Weiquan Ag–polymetallic deposit is located on the southern margin of the Central Asian Orogenic Belt and in the western segment of the Aqishan–Yamansu arc belt in East Tianshan, northwestern China. Its orebodies, controlled by faults, occur in the lower Carboniferous volcano‐sedimentary rocks of the Yamansu Formation as irregular veins and lenses. Four stages of mineralization have been recognized on the basis of mineral assemblages, ore fabrics, and crosscutting relationships among the ore veins. Stage I is the skarn stage (garnet + pyroxene), Stage II is the retrograde alteration stage (epidote + chlorite + magnetite ± hematite ± actinolite ± quartz), Stage III is the sulfide stage (Ag and Bi minerals + pyrite + chalcopyrite + galena + sphalerite + quartz ± calcite ± tetrahedrite), and Stage IV is the carbonate stage (quartz + calcite ± pyrite). Skarnization, silicification, carbonatization, epidotization, chloritization, sericitization, and actinolitization are the principal types of hydrothermal alteration. LA–ICP–MS U–Pb dating yielded ages of 326.5±4.5 and 298.5±1.5 Ma for zircons from the tuff and diorite porphyry, respectively. Given that the tuff is wall rock and that the orebodies are cut by a late diorite porphyry dike, the ages of the tuff and the diorite porphyry provide lower and upper time limits on the age of ore formation. The δ13C values of the calcite samples range from −2.5‰ to 2.3‰, the δ18OH2O and δDV‐SMOW values of the sulfide stage (Stage III) vary from 1.1‰ to 5.2‰ and −111.7‰ to −66.1‰, respectively, and the δ13C, δ18OH2O and δDV‐SMOW values of calcite in one Stage IV sample are 1.5‰, −0.3‰, and −115.6‰, respectively. Carbon, hydrogen, and oxygen isotopic compositions indicate that the ore‐forming fluids evolved gradually from magmatic to meteoric sources. The δ34SV‐CDT values of the sulfides have a large range from −6.9‰ to 1.4‰, with an average of −2.2‰, indicating a magmatic source, possibly with sedimentary contributions. The 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb ratios of the sulfides are 17.9848–18.2785, 15.5188–15.6536, and 37.8125–38.4650, respectively, and one whole‐rock sample at Weiquan yields 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb ratios of 18.2060, 15.5674, and 38.0511, respectively. Lead isotopic systems suggest that the ore‐forming materials of the Weiquan deposit were derived from a mixed source involving mantle and crustal components. Based on geological features, zircon U–Pb dating, and C–H–O–S–Pb isotopic data, it can be concluded that the Weiquan polymetallic deposit is a skarn type that formed in a tectonic setting spanning a period from subduction to post‐collision. The ore materials were sourced from magmatic ore‐forming fluids that mixed with components derived from host rocks during their ascent, and a gradual mixing with meteoric water took place in the later stages. [ABSTRACT FROM AUTHOR]