In present study, the feasibility of applying a natural adsorbent with Fe3+ modification (Fe3+-modified argillaceous limestone, FAL) on the competitive adsorption of heavy metals (i.e., Cd2+, Pb2+ ...and Ni2+) was evaluated. The current results revealed an efficient adsorption on Cd2+, Pb2+ and Ni2+ in mono-metal system. Further experiments demonstrated a high selectivity of Pb2+ during the competitive adsorption of Cd2+, Pb2+ and Ni2+. The adsorption selectivity of the metal ions followed the order of Pb ≫ Cd > Ni. In addition, both pH and ionic strength are important factors affecting the metal adsorptions. It is interestingly that various NOMs (i.e., humic acid (HA) and glycine (Gly)) exerted different effects on the adsorption behaviors, probably due to the different affinities for Pb2+, Cd2+ and Ni2+ and the redistribution of newly-formed metal-DOM complexes. X-ray photoelectron spectroscopy (XPS) analysis together with X-ray diffraction (XRD) and energy dispersive spectrometer (EDS) analysis revealed that the metal adsorptions were mainly regulated via the synergistic mechanisms of ion exchange by Na+, Ca2+, and Al3+, precipitation to form CdCO3 and Pb2(OH)2(CO3)2, as well as complexes of FAL-OPb and FAL-ONi by hydroxyl groups on the surface of FAL. The application of FAL would be a promising option in leading to an efficient heavy metal removal.
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•Fe3+-modified argillaceous limestone showed effective adsorption of Cd2+/Pb2+/Ni2+.•The adsorption selectivity of the metals followed the order of Pb ≫ Cd > Ni.•Both pH and ionic strength played key roles in metal adsorption.•Humic acid and glycine exerted distinct effects on adsorption behaviors of metals.•Mechanisms of metal adsorption were ion exchange, precipitation and complexation.
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•Jiangjin District located in Red Beds zone is a Se-enriched region in China.•Se content in topsoil in the northeast is higher than that of the midwest.•Se exhibited a negative ...correlation with the coefficient of weathering and eluviation.•Organic matter primarily controlled the spatial variation of soil Se content.
Selenium (Se) is an essential micronutrient for humans given its varying health benefits. It is generally recognized that China has a wide belt of low-Se soil stretching from the northeast to southwest. Nevertheless, there are Se-enriched areas distributed in the low-Se belt of China. However, the quantificational relationships among soil properties, topographic characteristics, parent materials, land use and soil Se content in those Se-enriched soils remain to be elucidated. Similarly, the key driving factors of the Se-enriched soil in the low-Se geological belt need to be documented. These aims could be an useful basis for evaluating the health of the soil ecosystem (in terms of Se toxicity or deficiency) and the potential intake of Se by humans from soils to food crops and animal products. To solve the above questions, Jiangjin district, Chongqing City, as an area in low Se red beds, was selected, and 156 topsoil samples were collected to explore the relationships between Se content in topsoil under various land use type and soil properties (pH, organic matter (OM), major elements content in topsoil) and topographic characteristics such as elevation (H), slope (SL), and topographic wetness index (TWI) and geological condition (stratum). Geostatistics, principal component analysis (PCA) and Geodetector were used to analyze the controlling factors of Se distribution in topsoil. The results show that in the analyzed topsoil (1) Se contents vary from 0.039 to 1.110 mg/kg, with a mean of 0.315 mg/kg, and higher than the background value of Chinese soil (0.290 mg/kg). 82.3% are classified as having moderate Se levels (Se > 0.175 mg/kg). (2) The Se contents in northeast of Jiangjin district are higher (Se > 0.315 mg/kg) than the midwest (Se < 0.315 mg/kg). (3) The key controlling factor of the soil Se distribution is OM. In addition, the soil weathering and leaching process and pedogenic rock are the secondary factors controlling Se distribution. Together, these findings reveal that Se-rich soil of low Se belt tends to be distributed in regions with higher OM, stronger leaching, and carbonate parent materials. These observations are beneficial to explore the Se-rich soil resources in low Se region in China.
Strategies for reducing cadmium (Cd) content in polluted farmland soils are currently limited. A type of composite with nanoparticles incorporated into a hydrogel have been developed to efficiently ...remove heavy metals from sewage, but their application in soils faces challenges, such as organic hydrogel degradation due to oxygen exposure and slow Cd2+ release from soil constituents. To overcome these challenges, a composite with superior stability for long-term application in soil is required. In this study, ferrous sulfide (FeS) nanoparticle@lignin hydrogel composites were developed. The lignin-based hydrogels inherited lignin’s natural mechanical and environmental stability and the FeS nanoparticles efficiently adsorbed Cd2+ and enhanced Cd2+ desorption from soils by producing H+. The high sorption capacity (833.3 g kg−1) of the composite was attributed to four proposed mechanisms, including cadmium sulfide (CdS) precipitation via chemical reaction (84.06%), lignin complexation (13.19%), hydrogel swelling (0.61%), and nanoparticle sorption (2.15%). In addition, Fe2+ displaced from the composite was gradually oxidized to form solid iron oxide hydroxide, which increased Cd2+ sorption. The composite significantly reduced the total, surfactant-soluble, and fixed Cd in heavily and lightly polluted paddy soils by 22.4–49.6%, 13.5–68.6%, and 40.1–16.6%, respectively, in 7 days.
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•The synthesized nFeS@lh reduced soil total and stable Cd by 16.6–49.6% in 7 days.•Lignin hydrogel realized the efficient dispersion and recovery of FeS nanoparticles.•The nFeS@lh had a high Cd sorption capacity (833.3 g kg−1) and mechanical strength.•The relative contributions of four sorption mechanisms were quantitively evaluated.
Dyslipidemia is a leading risk factor for cardiovascular and cerebrovascular diseases. By collecting the blood lipid profiles among adult residents of Shenmu City in Shaanxi Province, China, we aim ...to assess and elucidate the prevalence and risk factors of dyslipidemia in this city.
Stratified multistage sampling was used to survey 4,598 permanent adult residents in five areas of Shenmu (2 communities in the county seat, 2 in the southern area and 2 in the northern area) from September 2019 to December 2019. Questionnaire surveys and physical examinations were conducted. Data were analyzed using SPSS software version 26.0.
The average level of total cholesterol (TC) is 4.47mmol/L, that of triglyceride (TG) 1.32mmol/L, high-density lipoprotein cholesterol (HDL-C) 1.27mmol/L, apolipoprotein A1 (ApoA1) 1.44g/L, low-density lipoprotein cholesterol (LDL-C) 2.7mmol/L and apolipoprotein B (ApoB) 0.97g/L. The prevalence of hypercholesterolemia (HTC), hypertriglyceridemia (HTG), low high-density lipoprotein (HDL-C) and high low-density lipoprotein (LDL-C) is 22.4%, 33.3%, 14.5%, and 5.81%, respectively, and the overall prevalence of dyslipidemia is 48.27%. Furthermore, blood lipid levels and prevalence of dyslipidemia vary by region, age, gender, occupation and educational level. Nine risk factors of dyslipidemia were identified, which are living in county seat or northern industrial area, increasing age, male, overweight or obesity, abdominal obesity, smoking, hypertension, abnormal glucose metabolism (pre-diabetes or diabetes) and hyperuricemia.
The blood lipid levels and dyslipidemia prevalence of adults in Shenmu City are higher comparing to national averages of China. Combining risk factors of dyslipidemia, early detection and public health interventions are necessary in high-risk population for associated cardiovascular and cerebrovascular diseases prevention.
To determine the hydrochemical characteristics and health risks associated with their use as drinking water, 54 river water and 44 groundwater samples were collected and analyzed in a rural area of ...Jiangjin District, Chongqing City. The concentration of solutes in river water and groundwater showed significant spatial variability in the region. A number of dissolved chemical constituents including nitrate (NO
3
−
), nitrite (NO
2
−
), aluminum (Al), arsenic (As), boron (B), barium (Ba), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb) and selenium (Se) exceeded their respective recommended drinking water limits at some locations. Ternary plots of cations, anions and silica indicated that carbonate weathering was the primary source of major ions in water, followed by silicate weathering. Elevated concentrations of some chemical constituents including NO
3
−
and chloride (Cl
−
) were found in water samples in areas with the most intensive agricultural land use activities. A health risk assessment indicated that Cl
−
and NO
3
−
were the most important chemical constituents that were a non-carcinogenic health concern. A carcinogenic health risk assessment indicated that chromium (Cr) and As were the chemical constituents of most concern in water from the area that might be used as a drinking water source. The average annual carcinogenic risks for Cr in drinking water were determined to be in the range of 3.14E−05 and 7.90E−05 for adults and children, respectively. Similarly, the average annual carcinogenic risks for As in drinking water for adults and children were calculated to be in the range of 4.43E−07 and 1.11E−06, respectively. These values are within the risk values of 10
−6
to 10
−4
, which generally indicate that there are health concerns that need to be addressed in more detail. The highest values of carcinogenic risk for drinking water were mainly located in the northern part of the study area where there are industrial activities that are potential sources of arsenic and chromium in surface water and groundwater.
Sodium ion batteries (SIBs) are promising candidates for the applications of large-scale energy storage due to their cost-effective and environmental-friendly characteristics. Nevertheless, it ...remains a practical challenge to find a cathode material of SIBs showing ideal performance (capacity, reversibility, etc.). We report here a nanocomposite material of amorphous, porous FePO4 nanoparticles electrically wired by single-wall carbon nanotubes as a potential cathode material for SIBs. The hydrothermally synthesized nanocomposite shows excellent cell performance with unprecedented cycling stability and reversibility. The discharge capacity of as high as 120 mAh/g is delivered at a 0.1 C rate (10 mA/g). The capacity retentions are about 70 mAh/g, 60 mAh/g, and 55 mAh/g at higher currents of 20 mA/g, 40 mA/g, and 60 mA/g, respectively. Even at a 1 C rate (100 mA/g), a capacity of about 50 mAh/g is still retained after 300 cycles. With a simple synthetic procedure, cost-effective chemicals, and desirable cell performance, this method offers a highly promising candidate for commercialized cathode materials of SIBs.
Effective density (ρe) is universally used in atmospheric science as an alternative measure of the density (ρ) of aerosol particles, and its definitions can be expressed in terms of the particle mass ...(mp), ρ, mobility diameter (Dm), vacuum aerodynamic diameter (Dva), and dynamic shape factor (χ), as ρeI = 6mp/(π∙Dm3), ρeII = ρ/χ, and ρeIII = Dva/Dm. However, the theoretical foundation of these three definitions of ρe is still poorly understood before their application. Here, we explore the relationship between ρe and aerosol size through theoretical calculation. This study finds, for the first time, that ρeI and ρeIII inherently decrease with increasing size for aspherical particles with a fixed ρ and χ. We further elucidate that these inherent decreasing tendencies are governed by χ, and the ratio of the Cunningham Slip Correction Factor of the volume-equivalent diameter to that of the mobility diameter (Cc(Dve)/Cc(Dm)), but not by ρ. Taking the variable χ into consideration, the relationships of ρeI and ρeIII to particle size become more complicated, which suggests that the values of ρeI and ρeIII have little indication of the size-resolved physicochemical properties of particles. On the contrary, ρeII is independent on size for fixed χ and ρ, which indicates that the change in ρeII with size can better indicate the change in morphology and the transformation of the chemical compositions of particles. Our new insights into the essence of three ρes provide an accurate and crucial theoretical foundation for their application.
This work demonstrates the effect of atomic layer deposited (ALD) Al2O3 on the reactivation of dissolved polysulfides in Li–S batteries. A 0.5nm thick layer of Al2O3 is conformally coated onto highly ...porous carbon cloth by ALD, and then assembled in a Li–S battery between the sulfur cathode and the anode side (separator and Li anode) to function as a reactivation component. Compared to half cells with no ALD treatment, the ultrathin Al2O3 coating increases the specific discharge capacity by 25% from 907 to 1136mAh/g at the 1st cycle, and by 114% from 358 to 766mAh/g at the 40th cycle. Thus the ALD-Al2O3 improves the initial specific capacity and stabilizes the cycle life remarkably. Scanning electron microscopy and energy-dispersive X-ray spectroscopy results indicate that the ALD-Al2O3 coated carbon cloth sorbs (adsorbs/absorbs) more dissolved sulfur species from the electrolyte. Potential mechanisms for the improved sorption properties are proposed. The combination of an ultrathin ALD-oxide coating with highly porous carbons presents a new strategy to improve the performance of Li–S batteries.
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•Propose a concept that recollection/reactivation, instead of confinement (usually used), of dissolved polysulfidesfor improvement of Li-S battery performance.•Combination of atomic layer deposition (ALD) with nanoporousactive carbon to engineer the surface chemistryand pore size to enhance the sorption (absorption and adsorption) of lithium polysulfides.•Development of sulfur cathode configuration for next generation of rechargeable batteries with high energy and long cycling life.
Heavy metal stress in soil accelerates the plant root exudation of organic ligands. The degradation of exudate ligands can be fundamental to controlling the complexation of heavy metals. However, ...this process remains poorly understood. Here, we investigated the relationship between the transformation of glycine, a representative amino acid exudate, and cadmium/lead mobility in soils. Two 48-h incubation experiments were conducted after glycine addition to the soils. Parameters related to glycine distribution and degradation, Cd/Pb mobility, and the formation of glycine-Cd complex were analyzed. Glycine addition gradually decreased the Cd and Pb mobility throughout the 48-h incubation. By the end of the experiment, the CaCl2-extracted Cd and Pb concentrations decreased by 63.5% and 43.6%, respectively. The glycine mineralization was strong in the first 6 h, as indicated by a sharp decrease in CO2 efflux rates from 10.04 ± 0.62 to 3.51 ± 0.07 mg C–CO2 kg−1 soil h−1. The mineralization rates notably decreased after 6 h. The comparisons of dissolved organic carbon and hydrolyzable amino acid contents indicated that glycine mineralization in solution (95.6%) was much stronger than that in soil solids (49.3%). At the end of incubation, 0.22 mmol kg−1 glycine remained in soil solids. The remaining glycine provided sufficient sorption sites for Cd2+ and Pb2+, resulting in enhanced metal fixation via complexation. Comparisons of zeta potentials supported the formation of the glycine-Cd complex. The Cd and Pb immobilization processes could be attributed to metal-glycine complex formation, sorption re-equilibrium, and glycine degradation. These findings emphasize that the biogeochemical processes of glycine, derived from root exudates or protein degradation products, increased the sorption of heavy metals to soils and thus reduced their toxicity to plants.
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Glycine decreased soil Pb & Cd mobilities by 43.6% & 63.5% after 48 h incubation.The glycine mineralization in soil solution was much faster than that in soil solids.The remaining glycine in soil provided sufficient sorption sites for Cd2+ and Pb2+.Glycine complexation and degradation in soil accounted for Cd and Pb immobilization.Glycine may be an in vitro detoxification strategy of plant under Cd and Pb stresses.
Reducing the metal mobility in soil using glycine could be a self-defense strategy of plants.
BackgroundHigh blood pressure is a leading cardiovascular disease risk factor and considered to be associated with psychological factors. However, the causal relationships between blood pressure and ...anxiety, depressive symptoms, neuroticism and subjective well-being are not clear.AimsThe current study explored the genetic causal relationships between blood pressure and anxiety, depressive symptoms, neuroticism and subjective well-being.MethodsMendelian randomisation (MR) analyses were performed using the generalised summary-data-based MR analysis method with eight large-scale genome-wide association study datasets for hypertension, systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse pressure, anxiety, depressive symptoms, neuroticism and subjective well-being.ResultsA causal effect of DBP on neuroticism was found, and 1074 independent instrumental single nucleotide polymorphisms were identified by the incorporated Heterogeneity in Dependent Instruments-outlier test among the bidirectional causal relationship between blood pressure and the four psychological states.ConclusionsDBP has a causal effect on neuroticism. Appropriate management of blood pressure may reduce neuroticism, neuroticism-inducing mood disorders and cardiovascular diseases.
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