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Ecological water replenishment is an important measure for conserving water sources and improving the water environment. To explore the evolution and causes of groundwater chemistry after ecological water replenishment in the Jialu River, this study utilized groundwater monitoring data from 2015 to 2019 following ecological water replenishment. Various methods, including Piper’s trilinear diagram, Gibbs diagram, principal component analysis, and ion ratio analysis, were employed for research purposes. The results indicate that (1) since the implementation of ecological water replenishment in the Jialu River, there has been a general downwards trend in total dissolved solids (TDS) in groundwater. The dominant cation in groundwater is Ca 2+ , whereas HCO 3 − is the dominant anion. The concentration of cations in groundwater has generally decreased, with noticeable reductions in SO 4 2− and Cl − concentrations in the upper reaches of the recharge river contributing to improved groundwater quality. (2) A comparison with 2015 reveals a gradual transition at sampling points from chemical types such as HCO 3 -Ca·Mg and HCO 3 ·Cl–Ca·Mg to an ecological water replenishment chemical type (HCO 3 -Ca).

Groundwater is a vital water source for human survival and regulates the hydrological cycle within the uppermost strata. Through the processes of recharge and discharge, as well as solute exchange, it interacts with surface water systems in Zhengzhou, e.g., the Yellow River and the Jialu River. Therefore, systematically assessing its hydrochemical characteristics, driving factors, and health risks is crucial for ensuring the safety of public drinking water and regional development. This study focuses on shallow (45~55 m), medium-deep (80~350 m), deep (350~800 m), and ultra-deep (800~1200 m) groundwater in Zhengzhou City. A descriptive statistical analysis was employed to identify the primary chemical constituents of groundwater at various depths within the study area. Piper diagrams and the Shukarev classification method were employed to determine the hydrochemical types of the groundwater. Additionally, Gibbs diagrams, correlation coefficient methods, ion ratio coefficient methods and chlorine–alkali indices were employed to investigate the formation mechanisms of the chemical components of the groundwater, and the health risks in the study area were evaluated. Results: Ca2+ dominates the shallow/medium-deep groundwater, Na+ dominates the deep/ultra-deep groundwater; HCO3− (70~82%) is the dominant anion. Water chemistry shifts from HCO3-Ca to HCO3-Na with depth. Solubilisation, cation exchange, counter-cation exchange, and mixed processes primarily govern the formation of the groundwater’s chemical composition in the study area. Nitrate health risk assessments indicate significant differences in non-carcinogenic risks across four population groups (infants, children, young adults, and adults). Medium-depth groundwater poses a potential risk to all groups, while shallow and deep groundwater threaten only infants. Ultra-deep groundwater carries the lowest risk.

Groundwater in the Qingshui River Plain of southern Ningxia is one of the main water sources for local domestic and agricultural use. However, due to the geological background of the area, 33.94% of the groundwater samples had fluoride concentrations that exceeded the WHO drinking water standards. To examine the spatial patterns and formation processes of fluoride in groundwater, researchers gathered 79 rock samples, 2618 soil samples, 21 sediment samples, 138 groundwater samples, and 82 surface water samples across the southern Qingshui River Plain. The collected data were analyzed using statistical approaches and hydrogeochemical diagrams. The findings reveal that fluoride levels in groundwater exhibit a gradual increase from the eastern, western, and southern peripheral sloping plains toward the central valley plain. Vertically, higher fluoride concentrations are found within 100 m of depth. Over a ten-year period, fluoride concentrations have shown minimal variation. Fluoride-rich rocks, unconsolidated sediments, and soils are the primary sources of fluoride in groundwater. The primary mechanisms governing high-fluoride groundwater formation are rock weathering and evaporative concentration, whereas cation exchange adsorption promotes fluoride (F−) mobilization into the aquifer. Additional sources of fluoride ions include leaching of fluoride-rich sediments during atmospheric precipitation infiltration and recharge from fluoride-rich surface water.

With the large-scale closure of coal mines leading to groundwater pollution, in order to systematically identify the sources of major chemical ions in surface water and groundwater. This study comprehensively applied methods such as Piper’s trilinear diagram, linear fitting, and correlation analysis to quantitatively analyze the hydrochemical characteristics of closed coal mining areas in southwest Shandong and to clarify the sources of geochemical components in surface water and groundwater, and the PMF model was used to analyze the sources of chemical components in mine water and karst water. The results show that the concentrations of TDS ( Total Dissolved Solids), SO42−, Fe, and Mn in the mine water of the closed coal mine area are higher than in the karst water. Both water bodies are above groundwater quality standards. Ca2+, SO42−, and HCO3− dominate the ionic components in surface water and different types of groundwater. The hydrochemical types of surface, pore, and mine waters are mainly SO4-HCO3-Ca, whereas SO4-HCO3-Ca and HCO3-SO4-Ca dominate karst waters. SO42− is the leading ion in the TDS of water bodies. The mineralization process of surface water is mainly controlled by the weathering of silicate minerals, while that of the groundwater is mainly controlled by the dissolution of carbonate minerals. The impact of mining activities on surface water and groundwater is significant, while the impact of agricultural activities on surface water and groundwater is relatively small. The degree of impact of coal mining activities on SO42− concentrations in surface water, pore water, and karst water, in descending order, is karst water, surface water, and pore water. The PMF (Positive Matrix Factorization) model analysis results indicate that dissolution of carbonate minerals with sulphate and oxidation dissolution of sulfide minerals are the main sources of chemical constituents in mine waters. Carbonate dissolution, oxidation dissolution of sulfide minerals, domestic sewage, and dissolution of carbonate minerals with sulphate are ranked as the main sources of chemical constituents in karst water from highest to lowest. These findings provide a scientific basis for the assessment and control of groundwater pollution in the areas of closed coal mines.

The limited studies were performed to clarify the hydrogeochemical processes and mechanisms of subsidence pools in coal mining area. In this study, the surface water samples were collected from subsidence pools in coal mining area of Northern Anhui Province, China. Based on the determination on physicochemical parameters, the statistical analysis, Piper diagram, Gibbs model diagram, ion ratio methods, and the self-organizing map were applied to interpret the hydrochemical characteristics and genesis. The results showed that the dominance order of main cations was Na +  > Mg 2+  > Ca 2+  > K + , with the average anionic concentrations followed the order of HCO 3 −  > SO 4 2−  > Cl −  > NO 3 − . The hydrochemical types from the pools subsided for more than years were HCO 3 -Na type, while the subsidence pools formed in less than 20 years mainly presented SO 4 ·Cl-Na type. The weathering and dissolution of silicate rock and halite controlled the hydrogeochemical processes, but the contribution of evaporite minerals cannot be excluded in study area. The dominate mechanism was rock weathering, when the positive ion exchange of Ca 2+ and Mg 2+ replacing Na + and K + and coal mining activities had some effect on the hydrochemical process. Na + and HCO 3 − mainly came from the weathering and dissolution of sodium-containing silicate minerals, when the dissolution of silicate minerals and evaporate minerals was main sources of Ca 2+ and Mg 2+ . SO 4 2− mainly derived from the gypsum dissolution, along with its high SO 4 2− concentration resulting from human mining activities. This study will provide the effective information for protecting water resources in coal mining areas.

The paper took Taiyuan-Zhongwei-Yinchuan Railway as a background and the study focused on the frost damage there. First of all, the influence on the line operation was mentioned, discussing the status quo and the characteristics of the damage; next, by means of on-site investigation and testing, the phenomenon in the typical frost damage zone along the Railway was analyzed with the damages being classified; simultaneously, taking the track bed and the subgrade bed as the objectives, the damages were studied from the aspect of soil, water and temperature; last, the genesis and mechanism of the frost damage to the Lanzhou-Xinjiang Railway subgrade was generalized, offering the basis of the treatment.

Issue Title: The Composition of Matter The concentrator on Genesis provided samples of increased fluences of solar wind ions for precise determination of the oxygen isotopic composition. The concentration process caused mass fractionation as a function of the radial target position. This fractionation was measured using Ne released by UV laser ablation and compared with modelled Ne data, obtained from ion-trajectory simulations. Measured data show that the concentrator performed as expected and indicate a radially symmetric concentration process. Measured concentration factors are up to 30 at the target centre. The total range of isotopic fractionation along the target radius is 3.8%/amu, with monotonically decreasing ^sup 20^Ne/^sup 22^Ne towards the centre, which differs from model predictions. We discuss potential reasons and propose future attempts to overcome these disagreements. [PUBLICATION ABSTRACT]

When Mieke Bal reread the story of Joseph and Potiphar’s wife as an adult, she was struck by differences between her childhood memories of a moral tale and what she read today. In Loving Yusuf¸ Bal seeks to resolve this clash between memory and text, using the same story, in which Joseph spurns the advance of his master’s wife who then falsely accuses him of rape, as her point of departure. She juxtaposes the Genesis tale to the rather different version told in the Qur’an and the depictions of it by Rembrandt and explores how Thomas Mann’s great retelling in Joseph and His Brothers reworks these versions. Through this inquiry she develops concepts for the analysis of texts that are both strange and overly familiar—culturally remote yet constantly retold. As she puts personal memories in dialogue with scholarly exegesis, Bal asks how all of these different versions complicate her own and others’ experience of the story, and how the different truths of these texts in their respective traditions illuminate the process of canonization.

Scheelite from 25 representative orogenic gold deposits from various geological settings was investigated by EPMA (electron probe micro-analyzer) and LA-ICP-MS (laser ablation-inductively coupled plasma-mass spectrometer) to establish discriminant geochemical features to constrain indicator mineral surveys for gold exploration. Scheelite from orogenic gold deposits displays five REE patterns including a bell-shaped pattern with a (i) positive or (ii) negative Eu anomaly; (iii) a flat pattern with a positive Eu anomaly and, less commonly, (iv) a LREE-enriched pattern, and (v) a HREE-enriched pattern. The REE patterns are interpreted to reflect the source of the auriferous hydrothermal fluids and, perhaps, co-precipitating mineral phases. Scheelite from deposits formed in rocks metamorphosed at upper greenschist to lower amphibolite facies have low contents in REE, Y, and Sr, and high contents in Mn, Nb, Ta, and V, compared to scheelite formed in rocks metamorphosed below the middle greenschist facies. Scheelite from deposits hosted in sedimentary rocks has high Sr, Pb, U, and Th, and low Na, REE, and Y, compared to that hosted in felsic to intermediate rocks. Statistical analysis including elemental plots and multivariate statistics with PLS-DA (partial least square-discriminant analysis) reveal that the metamorphic facies of the host rocks as well as the regional host rock composition exert a strong control on scheelite composition. This is a result of fluid-rock exchange during fluid flow to gold deposition site. PLS-DA and elemental ratio plots show that scheelite from orogenic gold deposits have distinct Sr, Mo, Eu, As, and Sr/Mo, but indistinguishable REE signatures, compared to scheelite from other deposit types.

The rotation velocities in the outer disks of six massive star-forming galaxies are shown to decrease with disk radius, owing to high baryonic mass fractions and large velocity dispersions. Early galaxies not so dark In the cold dark matter cosmology, the baryonic components of galaxies (stars and gas) are thought to be mixed with non-baryonic and non-relativistic dark matter, which dominates the total mass. In the local Universe, dark matter dominates the outer, baryonic regions of the disks of star-forming galaxies, leading to rotation velocities of the visible matter within the disk that are constant or increase with disk radius—an essential feature of the dark-matter model. Reinhard Genzel et al . now report rotation curves for the outer disks of six massive, high-redshift star-forming galaxies and find that the rotation velocities decrease as radius increases. They propose a combination of two causes. First, these high-redshift galaxies were strongly baryon dominated, with dark matter playing a smaller part than in the local Universe and, second, the radial pressure gradient observed in the disks slows the rotation velocity as radius increases. The effect of both factors appears to increase with redshift. In the cold dark matter cosmology, the baryonic components of galaxies—stars and gas—are thought to be mixed with and embedded in non-baryonic and non-relativistic dark matter, which dominates the total mass of the galaxy and its dark-matter halo 1 . In the local (low-redshift) Universe, the mass of dark matter within a galactic disk increases with disk radius, becoming appreciable and then dominant in the outer, baryonic regions of the disks of star-forming galaxies. This results in rotation velocities of the visible matter within the disk that are constant or increasing with disk radius—a hallmark of the dark-matter model 2 . Comparisons between the dynamical mass, inferred from these velocities in rotational equilibrium, and the sum of the stellar and cold-gas mass at the peak epoch of galaxy formation ten billion years ago, inferred from ancillary data, suggest high baryon fractions in the inner, star-forming regions of the disks 3 , 4 , 5 , 6 . Although this implied baryon fraction may be larger than in the local Universe, the systematic uncertainties (owing to the chosen stellar initial-mass function and the calibration of gas masses) render such comparisons inconclusive in terms of the mass of dark matter 7 . Here we report rotation curves (showing rotation velocity as a function of disk radius) for the outer disks of six massive star-forming galaxies, and find that the rotation velocities are not constant, but decrease with radius. We propose that this trend arises because of a combination of two main factors: first, a large fraction of the massive high-redshift galaxy population was strongly baryon-dominated, with dark matter playing a smaller part than in the local Universe; and second, the large velocity dispersion in high-redshift disks introduces a substantial pressure term that leads to a decrease in rotation velocity with increasing radius. The effect of both factors appears to increase with redshift. Qualitatively, the observations suggest that baryons in the early (high-redshift) Universe efficiently condensed at the centres of dark-matter haloes when gas fractions were high and dark matter was less concentrated.