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1.
Small ; : e2310978, 2024 Mar 21.
Article in English | MEDLINE | ID: mdl-38513253

ABSTRACT

Rechargeable sodium chloride (Na-Cl2) batteries have emerged as promising alternatives for next-generation energy storage due to their superior energy density and sodium abundance. However, their practical applications are hindered by the sluggish chlorine cathode kinetics related to the aggregation of NaCl and its difficult transformation into Cl2. Herein, the study, for the first time from the perspective of electrode level in Na-Cl2 batteries, proposes a free-standing carbon cathode host with customized vertical channels to facilitate the SOCl2 transport and regulate the NaCl deposition. Accordingly, electrode kinetics are significantly enhanced, and the deposited NaCl is distributed evenly across the whole electrode, avoiding the blockage of pores in the carbon host, and facilitating its oxidation to Cl2. With this low-polarization cathode, the Na-Cl2 batteries can deliver a practically high areal capacity approaching 4 mAh cm-2 and a long cycle life of over 170 cycles. This work demonstrates the significance of pore engineering in electrodes for mediating chlorine conversion kinetics in rechargeable alkali-metal-Cl2 batteries.

2.
ACS Nano ; 18(4): 3542-3552, 2024 Jan 30.
Article in English | MEDLINE | ID: mdl-38215406

ABSTRACT

Prussian blue (PB) is one of the main cathode materials with industrial prospects for the sodium ion battery. The structural stability of PB materials is directly associated with the presence of crystal water within the open 3D framework. However, there remains a lack of consensus regarding whether all forms of crystal water have detrimental effects on the structural stability of the PB materials. Currently, it is widely accepted that interstitial water is the stability troublemaker, whereas the role of coordination water remains elusive. In this work, the dynamic evolution of PB structures is investigated during the crystal water (in all forms) removal process through a variety of online monitoring techniques. It can be inferred that the PB-130 °C retains trace coordination water (1.3%) and original structural integrity, whereas PB-180 °C eliminates almost all of crystal water (∼12.1%, including both interstitial and coordinated water), but inevitably suffers from structural collapse. This is mainly because the coordinated water within the PB material plays a crucial role in maintaining structural stability via forming the -N≡C-FeLS-C≡N- conjugate bridge. Consequently, PB-130 °C with trace coordination water delivers superior reversible capacity (113.6 mAh g-1), high rate capability (charge to >80% capacity in 3 min), and long cycling stability (only 0.012% fading per cycle), demonstrating its promising prospect in practical applications.

3.
J Environ Manage ; 344: 118421, 2023 Oct 15.
Article in English | MEDLINE | ID: mdl-37384986

ABSTRACT

Soil organic carbon (SOC), as a crucial measure of soil quality, is typically low in arid regions due to salinization, which is a global issue. How soil organic carbon changes with salinization is not a simple concept, as high salinity simultaneously affects plant inputs and microbial decomposition, which exert opposite effects on SOC accumulation. Meanwhile, salinization could affect SOC by altering soil Ca2+ (a salt component), which stabilizes organic matter via cation bridging, but this process is often overlooked. Here, we aimed to explore i) how soil organic carbon changes with salinization induced by saline-water irrigation and ii) which process drives soil organic carbon content with salinization, plant inputs, microbial decomposition, or soil Ca2+ level. To this end, we assessed SOC content, plant inputs represented by aboveground biomass, microbial decomposition revealed by extracellular enzyme activity, and soil Ca2+ along a salinity gradient (0.60-31.09 g kg-1) in the Taklamakan Desert. We found that, in contrast to our prediction, SOC in the topsoil (0-20 cm) increased with soil salinity, but it did not change with the aboveground biomass of the dominant species (Haloxylon ammodendron) or the activity of three carbon-cycling relevant enzymes (ß-glucosidase, cellulosidase, and N-acetyl-beta-glucosaminidase) along the salinity gradient. Instead, SOC changed positively with soil exchangeable Ca2+, which increased linearly with salinity. These results suggest that soil organic carbon accumulation could be driven by increases in soil exchangeable Ca2+ under salinization in salt-adapted ecosystems. Our study provides empirical evidence for the beneficial impact of soil Ca2+ on organic carbon accumulation in the field under salinization, which is apparent and should not be disregarded. In addition, the management of soil carbon sequestration in salt-affected areas should be taken into account by adjusting the soil exchangeable Ca2+ level.


Subject(s)
Carbon , Soil , Ecosystem , Calcium , Water , Sodium Chloride , Plants
4.
Nat Commun ; 14(1): 3767, 2023 Jun 24.
Article in English | MEDLINE | ID: mdl-37355646

ABSTRACT

Designing Pt-based electrocatalysts with high catalytic activity and CO tolerance is challenging but extremely desirable for alkaline hydrogen oxidation reaction. Herein we report the design of a series of single-atom lanthanide (La, Ce, Pr, Nd, and Lu)-embedded ultrasmall Pt nanoclusters for efficient alkaline hydrogen electro-oxidation catalysis based on vapor filling and spatially confined reduction/growth of metal species. Mechanism studies reveal that oxophilic single-atom lanthanide species in Pt nanoclusters can serve as the Lewis acid site for selective OH- adsorption and regulate the binding strength of intermediates on Pt sites, which promotes the kinetics of hydrogen oxidation and CO oxidation by accelerating the combination of OH- and *H/*CO in kinetics and thermodynamics, endowing the electrocatalyst with up to 14.3-times higher mass activity than commercial Pt/C and enhanced CO tolerance. This work may shed light on the design of metal nanocluster-based electrocatalysts for energy conversion.


Subject(s)
Lanthanoid Series Elements , Metals, Rare Earth , Platinum , Oxidation-Reduction , Carbon Monoxide , Hydrogen
5.
Chemosphere ; 325: 138319, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36898435

ABSTRACT

Soil inorganic carbon (SIC) accounts for 30-70% of the total soil C in global drylands. Despite the slow turnover rate, recent studies indicate that SIC could be altered by land-use change as soil organic C (SOC). Neglecting SIC change could contribute greatly to the uncertainty of soil C dynamics in drylands. However, due to the spatial-temporal variation in SIC, the direction and magnitude of SIC change (rate) induced by land-use change at a large spatial scale is understudied and poorly understood. Here, we used the space-for-time approach to test how the SIC change varied with the duration and type of land-use change and soil depth across China's drylands. We assessed the temporal and spatial variations in the SIC change rate and explored the influencing factors based on a regional dataset comprising 424 pairs of data across North China. We found that the SIC change rate of 0-200 cm after land-use change was 12.80 (5.47‒20.03) g C m-2 yr-1 (mean with 95% confidence interval), which was comparable to the SOC change rate (14.72, (5.27-24.15 g C m-2 yr-1)). Increased SIC occurred only in deep soils (>30 cm) and in the conversion from deserts to croplands or woodlands. In addition, the SIC change rate decreased with the duration of land-use change, implying that quantifying the temporal pattern of SIC change is necessary to accurately estimate SIC dynamics. The SIC change was strongly related to changes in soil water content. The SIC change rate was weakly and negatively correlated with the SOC change rate, and this relationship varied with soil depth. Together, this study highlights that to improve the prediction of soil C dynamics following land-use change in drylands, we should quantify the temporal and vertical patterns of both soil inorganic and organic C changes in the region.


Subject(s)
Carbon , Soil , Carbon/analysis , Forests , Water , China
6.
Nat Commun ; 13(1): 3797, 2022 07 01.
Article in English | MEDLINE | ID: mdl-35778395

ABSTRACT

Soil is the largest terrestrial reservoir of organic carbon and is central for climate change mitigation and carbon-climate feedbacks. Chemical and physical associations of soil carbon with minerals play a critical role in carbon storage, but the amount and global capacity for storage in this form remain unquantified. Here, we produce spatially-resolved global estimates of mineral-associated organic carbon stocks and carbon-storage capacity by analyzing 1144 globally-distributed soil profiles. We show that current stocks total 899 Pg C to a depth of 1 m in non-permafrost mineral soils. Although this constitutes 66% and 70% of soil carbon in surface and deeper layers, respectively, it is only 42% and 21% of the mineralogical capacity. Regions under agricultural management and deeper soil layers show the largest undersaturation of mineral-associated carbon. Critically, the degree of undersaturation indicates sequestration efficiency over years to decades. We show that, across 103 carbon-accrual measurements spanning management interventions globally, soils furthest from their mineralogical capacity are more effective at accruing carbon; sequestration rates average 3-times higher in soils at one tenth of their capacity compared to soils at one half of their capacity. Our findings provide insights into the world's soils, their capacity to store carbon, and priority regions and actions for soil carbon management.


Subject(s)
Carbon , Soil , Agriculture , Carbon Sequestration , Minerals
7.
Front Microbiol ; 13: 862245, 2022.
Article in English | MEDLINE | ID: mdl-35677905

ABSTRACT

Salinization poses great threats to soil fungal communities that would cause the losses of ecosystems services. Soil fungal communities are composed of different functional guilds such as saprotrophic, symbiotrophic, and pathotrophic fungi, and each guild includes many rare taxa and a few abundant taxa. Despite of low abundance, rare taxa may be crucial in determining the responses of entire soil fungal communities to salinization. However, it remains poorly understood how rare taxa mediate the impacts of soil salinization on soil fungal community structure. Here, we took advantage of a salinity gradient in a desert ecosystem ranging from 0.60 to 31.09 g kg-1 that was created by a 12-year saline-water irrigation and assessed how the rare vs. abundant taxa of soil saprotrophic, symbiotrophic, and pathotrophic fungi respond to soil salinization through changes in the community biodiversity and composition. We found that the rare taxa of soil saprotrophic, symbiotrophic, and pathographic fungi were more sensitive to changes in soil salinity compared to the abundant taxa. In addition, the community composition of rare taxa of the saprotrophic and pathotrophic fungi not the symbiotrophic fungi was positively associated with soil salinity change. However, the symbiotrophic fungi showed greater variations in the species richness along the salinity gradient. These findings highlight the importance to differentiate rare taxa in predicting how the biodiversity and functional groups of soil fungal communities respond to soil salinization.

8.
Glob Chang Biol ; 28(11): 3665-3673, 2022 06.
Article in English | MEDLINE | ID: mdl-35152535

ABSTRACT

Soils are important carbon (C) reservoirs and play a critical role in regulating the global C cycle. Soil water potential (SWP) measures the energy with which water is retained in the soil and is one of the most vital factors that constrain the decomposition of soil organic C (SOC). The measurements for soil water retention curve (SWRC), on which the estimation of SWP depends, are usually carried out above -1.5 MPa (i.e., the wilting point for many plants). However, the average moisture threshold at which soil microbial activity ceases is usually below -10 MPa in mineral soils. Beyond the measurement range, the SWP estimation has to be derived from extrapolating the SWRC, which violates the statistical principle, resulting in possibly inaccurate SWP estimations. To date, it is unclear to what extent the extrapolated SWP estimation deviates from the "true value" and how it impacts the modeling of SOC decomposition. This study combined SWRC measurements down to -43.7 MPa, a 72-day soil incubation experiment with four moisture levels, and an SOC decomposition model. In addition to the complete SWRC (SWRCall ), we fitted two more SWRCs by using measurements above -0.5 MPa (SWRC0.5 ) and -1.7 MPa (SWRC1.7 ), respectively, to quantify the deviations of extrapolated SWPs from the complete SWRC. Results showed that extrapolating the SWRC beyond its measurement range significantly underestimated the SWP. Incorporating the extrapolated SWP in the model significantly underestimated the SOC decomposition under relatively dry conditions. With the extrapolated SWP, the model predicted no SOC decomposition in the driest treatment, while the experiment observed a significant CO2 emission. The results emphasize that accurate SWP estimations beyond the wilting point are critically needed to improve the modeling of SOC decomposition.


Subject(s)
Soil , Water , Carbon , Plants
9.
Front Psychol ; 13: 1113655, 2022.
Article in English | MEDLINE | ID: mdl-36743651

ABSTRACT

On social media, luxury brand managers often use influencers' bragging language as a marketing tool. As modesty is considered a virtue in the Chinese context, Chinese influencers tend to adopt a humblebragging language style. Research has examined the impact of bragging language styles on luxury brands and has found that humblebragging, which appears to be modest, has a negative influence on brand attitudes. From the perspective of social comparison theory, we proposed a dual mediation model of malicious envy and trustworthiness to reveal the internal mechanisms and moderating factors of the negative effects of humblebragging. The results of three experiments indicated that compared with straightforward bragging, humblebragging was more likely to elicit malicious envy and lower levels of trust in an influencer, resulting in negative attitudes toward the luxury brand endorsed. Moreover, this negative effect was stronger when the influencer lacked expertise or had high similarity with consumers. Our findings enrich the antecedents of social media influencer marketing and provide managers with implications for maximizing the effectiveness of influencer marketing by matching influencers with word-of-mouth content.

10.
Front Psychol ; 12: 661851, 2021.
Article in English | MEDLINE | ID: mdl-34489785

ABSTRACT

Both happy and sad facial expressions of recipients are frequently used in charity advertisements. However, the relative effectiveness of these two types of facial expressions has been found paradoxical in the past. In this study, we examine when happy facial expression can more effectively increase donation intentions of consumers and when vice versa. Specially, we propose that eye contact between a donor and a potential recipient may moderate the relative effectiveness of happy and sad facial expressions, and further explain the interaction effect from the perspective of emotional intensity. Results from two experiments suggest that, when donor-recipient eye contact is present, consumers tend to have stronger emotional intensity, and, in turn, show higher donation intentions when the recipient is with a happy rather than sad facial expression. In contrast, when the eye contact is absent, consumers may show stronger emotional intensity and donation intentions toward the charity advertisement with a recipient showing sad rather than happy expression.

11.
Chemosphere ; 277: 130345, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34384187

ABSTRACT

Saline-sodic soils cover ∼10% of the global land surface and deliver various ecosystem services to human society in the arid/semiarid regions. Flue gas desulfurization gypsum (FGDG), a byproduct from coal-fired power plants, is widely used to ameliorate saline-sodic soils. Here, we aimed to quantify the impacts of FGDG application on multiple soil functions across climatic conditions, management practices, and soil types, and to explore how FGDG application affects plant productivity. We conducted a meta-analysis by compiling 2658 pairs of data points with and without FGDG application from 59 locations across China. We found that FGDG application significantly increased crop yield by 91.2% ± 22.5% (mean ± 95% CI) regardless of local climate and soil type, and improved soil quality by reducing soil exchangeable sodium percentage (ESP) by 37.4% ± 9.6% and pH by 8.1% ± 1.7%. Increases in soil productivity were strongly correlated with decreases in soil ESP and pH, suggesting that increases in soil productivity were due to alleviated stress for plant growth. Meanwhile, some heavy elements (e.g., Hg and Ni) increased after FGDG application, likely imposing threats to soil health. Overall, the FGDG application is effective in improving the quality and productivity of saline-sodic soils across China. Our findings suggest that simultaneous assessment of changes in soil water (e.g., water holding capacity and infiltration), nutrient transformation, soil organic matter dynamics, and microbial communities helps disentangle mechanisms that are responsible for optimizing ecosystem service provided by saline-sodic soils after FGDG amendment application.


Subject(s)
Mercury , Soil , Calcium Sulfate , Ecosystem , Gases , Humans
12.
J Environ Manage ; 292: 112755, 2021 Aug 15.
Article in English | MEDLINE | ID: mdl-33992868

ABSTRACT

Soil microbial biomass is key to improving the prediction of soil organic carbon (SOC) dynamics by modeling. However, the driving mechanism of microbial biomass of different groups with soil depth is poorly understood across sites. Here, we compiled the biomass of different microbial groups (i.e., fungi, bacteria, gram-positive bacteria G+, and gram-negative bacteria G-) from the surface to a soil depth of 1 m from 71 soil profiles across three continents. We found that the biomass of microbial groups all decreased with soil depth but at different magnitudes, while the relative abundance of microbial groups, except G-, was relatively stable along soil profiles. Soil fungal biomass had a shallower vertical distribution than bacteria, especially G+, with 89% fungi and 76% G+ in the top 10 cm soils. In addition, a greater proportion of microbial biomass (71-89%) compared to SOC (64%) was in the top 10 cm soils, suggesting that microbes and SOC exhibited different vertical distributions. The vertical distributions of microbial biomass of different groups were significantly correlated with SOC and clay content but not with climate, and these distributions were different among land uses, highlighting the great influences of edaphic factors on vertical distributions of microbial biomass. The relationship between microbial biomass and soil depth provides a feasible way to estimate microbial biomass at different soil depths, which can serve as a benchmark to improve the prediction of SOC dynamics of entire soil profile at large scales.


Subject(s)
Carbon , Soil , Biomass , Fungi , Soil Microbiology
13.
Nanoscale ; 13(4): 2481-2491, 2021 Jan 28.
Article in English | MEDLINE | ID: mdl-33471015

ABSTRACT

The electrode materials of potassium ion storage system have attracted considerable attention given the promising prospect of a potassium ion system in large-scale electrochemical energy storage applications. Despite the excellent anode performance of metal oxides in Li+ and Na+ batteries, the study on their K+ storage performance is still rarely reported. In this study, we report a safe and low-cost strategy to prepare FeOx/N-doped carbons by using NaHCO3 and Fe nanopowder. Benefiting from the oxidation of Fe to Fe3O4, an interesting "one stone, two birds" role of the Fe powder can be identified in the heating process. As a reduction agent, the Fe powder can consume the excess oxygen in the bio-massed carbon framework, facilitating the formation of short-range-ordered domains in the biomass-derived carbon materials (FeOx@GBHCs). Moreover, the close combination of oxidization products (Fe3O4 particles) and carbon matrix leads to numerous FeOx clusters grafted on the surface of the carbon framework via the strong C-O-Fe binding. Therefore, the resultant FeOx/porous carbon exhibits a high reversible capacity of 410 mA h g-1 and an excellent cycling capability. The assembled FeOx@GBHCs//AC potassium-ion hybrid supercapacitor delivers a high energy density of 133 W h kg-1 at a power density of 700 W kg-1, demonstrating a potential prospect of metal oxides in boosting the potassium ion storage performance.

14.
Data Brief ; 32: 106147, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32904338

ABSTRACT

Soil microbial biomass carbon (SMBC) is important in regulating soil organic carbon (SOC) dynamics along soil profiles by mediating the decomposition and formation of SOC. The dataset (VDMBC) is about the vertical distributions of SOC, SMBC, and soil microbial quotient (SMQ = SMBC/SOC) and their relations to environmental factors across five continents. Data were collected from literature, with a total of 289 soil profiles and 1040 observations in different soil layers compiled. The associated environment data collectd include climate, ecosystem types, and edaphic factors. We developed this dataset by searching the Web of Sciene and the China National Knowledge Infrastructure from the year of 1970 to 2019. All the data in this dataset met two creteria: 1) there were at least three mineral soil layers along a soil profile, and 2) SMBC was measured using the fumigation extraction method. The data in tables and texts were obtained from literature directly, and the data in figures were extracted by using the GetData Graph digitizer software version 2.25. When climate and soil properties were not available from publications, we obtainted the data from the World Weather Information Service (https://worldweather.wmo.int/en/home.html) and SoilGrids at a spatial resolution of 250 meters (version 0.5.3, https://soilgrids.org). The units of all the variables were converted to the standard international units or commonly used ones and the values were transformed correspondingly. For example, the value of soil organic matter (SOM) was converted to SOC by using the equation (SOC = SOM × 0.58). This dataset can be used in predicting global SOC changes along soil profiles by using the multi-layer soil carbon models. It can also be used to analyse how soil microbial biomass changes with plant roots as well as the composition, structure, and functions of soil microbial communities along soil profiles at large spatial scales. This dataset offers opportunities to improve our prediction of SOC dynamics under global changes and to advance our understanding of the environmental controls.

15.
Article in English | MEDLINE | ID: mdl-32912928

ABSTRACT

INTRODUCTION: Progressive distal symmetrical axonal neuropathy, a complication of diabetes mellitus (DM), has an unknown cause. Normal physiological metabolism and diabetic dysmetabolism are associated with the generation of γ-diketones. γ-Diketones form pyrroles with protein amines, notably with axonal proteins required for the maintenance of nerve fiber integrity, especially elongate, large-diameter peripheral nerve fibers innervating the extremities. We tested the hypothesis that neuropathy-associated γ-diketone pyrroles are elevated in DM. RESEARCH DESIGN AND METHODS: We measured the urinary concentration of γ-diketone pyrroles in age-matched and gender-matched elderly (60-84 years) persons with (n=267) or without (n=267) indicators of DM based in a community population (9411 community older adults aged ≥60 years) in Shenzhen city, Guangdong, China. We used statistical methods, including a generalized linear model, multivariate logistic regression analysis and restricted cubic splines, to assess linear and nonlinear relationships between urinary γ-diketone pyrroles and indicators of DM. RESULTS: Compared with healthy controls, those with DM had significantly higher levels of fasting blood glucose, glycated hemoglobin A1c, urinary ketone bodies and urinary γ-diketone pyrroles. The median concentration of urinary γ-diketone pyrrole adducts was significantly higher (p<0.0001) in individuals with DM (7.5 (5.4) µM) compared with healthy controls (5.9 (4.3) µM). Both linear and non-linear relations were found between urinary γ-diketone pyrroles and indicators of DM. CONCLUSIONS: Diabetic dysmetabolism includes increased generation and excretion of neuropathy-associated γ-diketone pyrroles. These findings form the foundation for studies to test whether γ-diketone pyrrole concentration correlates with quantitative sensory (vibration and temperature) and electrodiagnostic testing.


Subject(s)
Diabetes Mellitus , Peripheral Nervous System Diseases , Aged , Aged, 80 and over , Axons , China , Humans , Middle Aged , Pyrroles/adverse effects
16.
Nanoscale ; 12(19): 10816-10826, 2020 May 21.
Article in English | MEDLINE | ID: mdl-32393928

ABSTRACT

The design of electrodes with simultaneously high compaction density, developed porosity, and structural stability has always been a challenge so as to meet the demand of high volumetric performance lithium ion storage devices. In this paper, we demonstrate a new compositing method for hollow carbon "room" loading of Fe3O4 nanoparticles (HCR@Fe3O4) with the assistance of Na2CO3 salt crystal templates. The as-obtained HCR@Fe3O4 composites have a massive compaction density (1.79 g cm-3), abundant multimodal pores (1.26 cm3 g-1), and a large content of Fe3O4 (64.2 wt%), which leads to excellent volumetric capacitive performance. More importantly, the unique compositing model not only provides a fast transmission channel for Li+ but also alleviates the mechanical strain efficiently through the cavity between the Fe3O4 nanoparticles and the carbon wall. When evaluated as an anode of lithium ion batteries, the resultant HCR@Fe3O4 electrode exhibits a remarkable volumetric capacity of 2044 mA h cm-3 at 0.2 A g-1 and a stable cycle life of 828 mA h cm-3 after 1000 cycles at 5 A g-1. The assembled HCR@Fe3O4//AC lithium ion hybrid capacitor device exhibits a high energy density of 173 W h L-1 at a power density of 190 W L-1, demonstrating its high-level integrated volumetric density/power density.

17.
ACS Nano ; 14(4): 4938-4949, 2020 Apr 28.
Article in English | MEDLINE | ID: mdl-32271546

ABSTRACT

Potassium-ion energy-storage devices are highly attractive in the large-scale energy storage field, but the intercalation of large K ions greatly worsens the stability of electrode structures and solid electrolyte interphase (SEI) films, causing slow reaction dynamics and poor durability. In this Article, inspired by bubble wraps in our life, a bubble-wrap-like carbon sheet (BPCS) with a rigid-flexible coupling porous architecture is fabricated on the microscale, exhibiting strong structural stability and good accommodation for volume expansion. In the meantime, a K2CO3·1.5H2O-dominated SEI is created by an interfacial transfer behavior of carbonate groups. These K2CO3·1.5H2O nanograins not only enhance the stability of the SEI by constructing a stable scaffold but also create more diffusion routes for K ions. On the basis of the above, using the BPCS as the anode of potassium-ion batteries delivers reversible capacities of 463 mAh g-1 at 50 mA g-1 and 195 mAh g-1 at 10 A g-1 with a long cycling life. The assembled BPCS//NPC potassium-ion hybrid capacitor exhibits a high energy density of 167 Wh kg-1 and a superior cycling capability with 80.8% capacity retention over 10 000 cycles with nearly 100% Coulombic efficiency. Even at the higher current density of 10 A g-1, the device could deliver an energy density of 92.9 Wh kg-1 over 5000 cycles at a power density of 9200 W kg-1 with only 0.002% fading per cycle, which can rival lithium-ion hybrid supercapacitors.

18.
ACS Nano ; 13(10): 11582-11592, 2019 10 22.
Article in English | MEDLINE | ID: mdl-31560191

ABSTRACT

Bioinspired mineralization is a powerful method for designing and preparing nanomaterials. In this work, we developed a bioinspired mineralization approach under freezing conditions and fabricated methyl cellulose (MC)/NaHCO3 flake precursors with a sophisticated hierarchical structure. Based on this, amazing wing-like porous carbon sheets (WPCSs) assembled by numerous interconnected hollow carbon bubbles were obtained after carbonization and removal of inorganic crystals, which are seldom obtained by other artificial methods. Benefiting from their open framework, large surface area, and enlarged interlayer spacing of graphitized nanocrystallites, the obtained WPCSs exhibited an obvious boost in potassium storage performance. As an anode of potassium-ion batteries, they showed high reversible capacities of 347 mAh g-1 at 50 mA g-1 and 122 mAh g-1 at 20 A g-1 and relatively stable cyclability for 3000 cycles. The assembled WPCS//WPCS potassium-ion hybrid supercapacitor delivered a high energy density of 108 Wh kg-1 at a power density of 280 W kg-1. Given the cost effectiveness and green process, the modified bioinspired mineralization under freezing conditions would provide a facile and green way for exploring porous carbons with controlled structures and rich multifunction.

19.
Occup Environ Med ; 76(10): 758-764, 2019 10.
Article in English | MEDLINE | ID: mdl-31439688

ABSTRACT

OBJECTIVES: Experimental studies suggested that bisphenol A (BPA) exposure increased the risk of metabolic syndrome (MetS) through the mechanism of insulin resistance. All previous epidemiological studies of BPA and MetS were cross-sectional studies, and their findings were mixed. This study aims to provide further evidence on the association between urinary BPA and risk of MetS using a prospective cohort study in China. METHODS: The study population was from the Shenzhen Night shift workers' cohort. A total of 1227 male workers were recruited from the baseline survey in 2013 and then followed until 2017. Modified Adult Treatment Panel III criteria were used to identify the cases of MetS. Urinary BPA concentration was assessed using high-performance liquid chromatography-tandem mass spectrometry, and it was categorised into three subgroups by tertiles to obtain the adjusted HR (aHR) and 95% CI using Cox proportional hazard model. RESULTS: During 4 years of follow-up, 200 subjects developed MetS. Compared with the lowest urinary BPA subgroup, a weakly increased risk of MetS was suggested among those with the middle (aHR=1.19, 95% CI 0.87 to 1.63) and high level of urinary BPA (aHR=1.16, 95% CI 0.84 to 1.59); however, the significant association with MetS was restricted primarily to the smokers, showing a positive gradient with urinary BPA (middle level: aHR=2.40, 95% CI 1.13 to 5.08; high level: aHR=2.87, 95% CI 1.38 to 5.98; p trend=0.010). CONCLUSION: This prospective cohort study provided further evidence that exposure to BPA may increase the risk of MetS, and this association was further positively modified by cigarette smoking.


Subject(s)
Benzhydryl Compounds/urine , Metabolic Syndrome/epidemiology , Phenols/urine , Adult , China/epidemiology , Cigarette Smoking , Cohort Studies , Humans , Incidence , Male , Middle Aged , Prospective Studies
20.
ISME J ; 13(12): 2901-2915, 2019 12.
Article in English | MEDLINE | ID: mdl-31384013

ABSTRACT

The susceptibility of soil organic carbon (SOC) in tundra to microbial decomposition under warmer climate scenarios potentially threatens a massive positive feedback to climate change, but the underlying mechanisms of stable SOC decomposition remain elusive. Herein, Alaskan tundra soils from three depths (a fibric O horizon with litter and course roots, an O horizon with decomposing litter and roots, and a mineral-organic mix, laying just above the permafrost) were incubated. Resulting respiration data were assimilated into a 3-pool model to derive decomposition kinetic parameters for fast, slow, and passive SOC pools. Bacterial, archaeal, and fungal taxa and microbial functional genes were profiled throughout the 3-year incubation. Correlation analyses and a Random Forest approach revealed associations between model parameters and microbial community profiles, taxa, and traits. There were more associations between the microbial community data and the SOC decomposition parameters of slow and passive SOC pools than those of the fast SOC pool. Also, microbial community profiles were better predictors of model parameters in deeper soils, which had higher mineral contents and relatively greater quantities of old SOC than in surface soils. Overall, our analyses revealed the functional potential of microbial communities to decompose tundra SOC through a suite of specialized genes and taxa. These results portray divergent strategies by which microbial communities access SOC pools across varying depths, lending mechanistic insights into the vulnerability of what is considered stable SOC in tundra regions.


Subject(s)
Archaea/isolation & purification , Bacteria/isolation & purification , Carbon/analysis , Fungi/isolation & purification , Microbiota , Soil Microbiology , Archaea/classification , Archaea/genetics , Bacteria/classification , Bacteria/genetics , Carbon/metabolism , Climate Change , Fungi/classification , Fungi/genetics , Permafrost/microbiology , Soil/chemistry , Tundra
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