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1.
Glob Chang Biol ; 30(4): e17291, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38647225

RESUMEN

Terrestrial ecosystem resilience is crucial for maintaining the structural and functional stability of ecosystems following disturbances. However, changes in resilience over the past few decades and the risk of future resilience loss under ongoing climate change are unclear. Here, we identified resilience trends using two remotely sensed vegetation indices, analyzed the relative importance of potential driving factors to resilience changes, and finally assessed the risk of future resilience loss based on the output data of eight models from CMIP6. The results revealed that more than 60% of the ecosystems experienced a conversion from an increased trend to a declined trend in resilience. Attribution analysis showed that the most important driving factors of declined resilience varied regionally. The declined trends in resilience were associated with increased precipitation variability in the tropics, decreased vegetation cover in arid region, increased temperature variability in temperate regions, and increased average temperature in cold regions. CMIP6 reveals that terrestrial ecosystems under SPP585 are expected to experience more intense declines in resilience than those under SSP126 and SSP245, particularly in cold regions. These results highlight the risk of continued degradation of ecosystem resilience in the future and the urgency of climate mitigation actions.


Asunto(s)
Cambio Climático , Ecosistema , Temperatura , Modelos Teóricos
2.
Ambio ; 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38564103

RESUMEN

When accounting for the social-ecological impact of an ecological restoration program, both objective environmental contexts and people's subjective perceptions are required. While this kind of environmental impact assessment lacks a comprehensive perspective. We use the difference-in-differences model to evaluate the effect of the greenness of the landscape after ecological migration in the Qilian Mountains in China; and analysis of variance and fixed effects models are used to evaluate the effects of such ecological restoration programs on local people's perceptions. The results show that the ecological migration program in the Qilian Mountains has been successful at not only significantly improving remotely sensed greenness at the landscape scale, but also at enhancing immigrants' environmental perceptions. These findings demonstrate the environmental impacts of ecological migration from a social-ecological perspective, and can provide methodological implications for landscape planning to support a better understanding of ecological restoration programs in the drylands.

3.
J Environ Manage ; 356: 120617, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38537466

RESUMEN

Residents' environmental attitudes (EAs) towards ecological restoration programs are vital for evaluating program effectiveness and promoting environmental management. However, most local studies have neglected the indirect environmental contextual influences on residents' EAs, and have omitted the regional variations in the environmental contextual influences. To investigate the multilevel factors affecting residents' EAs, we conducted a transect survey that included the eastern, middle, and western regions in northern China's drylands, where have experienced ecological restoration. Multilevel linear models (MLMs) were applied to analyse the direct and indirect impacts of environmental contexts and individual characteristics on rural residents' EAs. The results showed the environmental context can indirectly impact EAs by amplifying the influence of individual characteristics such as family structure and income on EAs. The EAs are influenced by different local environmental contexts among the east, middle and west of China's drylands. The humidity attitude was influenced by precipitation only in the highly arid western and middle regions, while precipitation attitude is strongly influenced by land surface temperature and humidity in eastern China's drylands. These findings hold important implications for understanding the cross-scale impact of environmental contexts on EAs in drylands.


Asunto(s)
Actitud , Renta , Humanos , Población Rural , China
4.
Natl Sci Rev ; 11(2): nwad286, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38213521

RESUMEN

Kidney transplantation is the gold standard for the treatment of end-stage renal diseases (ESRDs). However, the scarcity of donor kidneys has caused more and more ESRD patients to be stuck on the waiting list for transplant surgery. Improving the survival rate for renal grafts is an alternative solution to the shortage of donor kidneys. Therefore, real-time monitoring of the surgical process is crucial to the success of kidney transplantation, but efficient methods and techniques are lacking. Herein, a fluorescence technology based on bright, photostable and long-circulating aggregation-induced emission (AIE) active NIR-II nano-contrast agent DIPT-ICF nanoparticles for the whole-process monitoring and evaluation of renal transplantation has been reported. In the aggregated state, DIPT-ICF exhibits superior photophysical properties compared with the commercial dyes IR-26 and IR-1061. Besides, the long-circulating characteristic of the AIE nano-contrast agent helps to achieve renal angiography in kidney retrieval surgery, donor kidney quality evaluation, diagnosing vascular and ureteral complications, and assessment of renal graft reperfusion beyond renovascular reconstruction, which considerably outperforms the clinically approved indocyanine green (ICG).

5.
J Colloid Interface Sci ; 648: 149-160, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37301140

RESUMEN

Due to their low cost and high stability, sodium-ion batteries have been increasingly studied. However, their further development is limited by the relative energy density, resulting in the search for high-capacity anodes. FeSe2 displays high conductivity and capacity but still suffers from sluggish kinetics and serious volume expansion. Herein, through sacrificial template methods, a series of sphere-like FeSe2-carbon composites are successfully prepared, displaying uniform carbon coatings and interfacial chemical FeOC bonds. Moreover, benefiting from the unique traits of precursor and acid treatment, rich structural voids are prepared, effectively alleviating volume expansion. Utilized as anodes of sodium-ion batteries, the optimized sample displays considerable capacity, achieving 462.9 mAh g-1, with 88.75% coulombic efficiency at 1.0 A g-1. Even at 5.0 A g-1, their capacity can be kept at approximately 318.8 mAh g-1, while the stable cycling can be prolonged to 200 cycles above. Supported by the detailed kinetic analysis, it can be noted that the existing chemical bonds facilitate the fast shuttling of ions at the interface, and the enhanced surface/near-surface properties are further vitrified. Given this, the work is expected to offer valuable insights for the rational design of metal-based samples toward advanced sodium-storage materials.

6.
J Colloid Interface Sci ; 641: 831-841, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36966572

RESUMEN

Mo-based heterostructures offer a new strategy to improve the electronics/ion transport and diffusion kinetics of the anode materials for sodium-ion batteries (SIBs). MoO2/MoS2 hollow nanospheres have been successfully designed via in-situ ion exchange technology with the spherical coordination compound Mo-glycerates (MoG). The structural evolution processes of pure MoO2, MoO2/MoS2, and pure MoS2 materials have been investigated, illustrating that the structureofthenanospherecan be maintained by introducing the S-Mo-S bond. Based on the high conductivity of MoO2, the layered structure of MoS2 and the synergistic effect between components, as-obtained MoO2/MoS2 hollow nanospheres display enhanced electrochemical kinetic behaviors for SIBs. The MoO2/MoS2 hollow nanospheres achieve a rate performance with 72% capacity retention at a current of 3200 mA g-1 compared to 100 mA g-1. The capacity can be restored to the initial capacity after a current returns to 100 mA g-1, while the capacity fading of pure MoS2 is up to 24%. Moreover, the MoO2/MoS2 hollow nanospheres also exhibit cycling stability, maintaining a stable capacity of 455.4 mAh g-1 after 100 cycles at a current of 100 mA g-1. In this work, the design strategy for the hollow composite structure provides insight into the preparation of energy storage materials.

7.
Small ; 18(1): e2105193, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34786835

RESUMEN

Given the inherent characteristics of transition metal fluorides and open tunnel-type frameworks, intercalation-conversion-type FeF3 ·0.33H2 O has attracted widespread attention as a promising lithium-ion battery cathode material with high operating voltage and high energy density. However, its low electronic conductivity and poor structural stability impede its practical application in high-rate capacity and long-lifetime batteries. Herein, rod-like Nb-substituted FeF3 ·0.33H2 O (Nb-FeF3 ·0.33H2 O@C) nanocrystals with a carbon coating derived from in situ carbonization in an ionic liquid are deliberately designed and prepared. Based on first-principles calculations and electrochemical analysis, it is shown that substitution of Nb into a proportion of Fe sites can dramatically reduce the total energy of the system and the bandgap, thus boosting the structural stability and electronic conductivity of FeF3 ·0.33H2 O. Simultaneously, the combination of a surface conductive carbon coating and assembly of the nanoparticles into a rod-like mesoporous architecture can produce an omni-directional ion/electron transmission network and a robust 3D composite structure. The Nb-FeF3 ·0.33H2 O@C composite with 3% Nb-doping displays high capacity (583.2 mAh g-1 at 0.2 C), good rate capacity (187.8 mAh g-1 at a high rate of 5.0 C), and excellent long-term cycle stability (160.4 mAh g-1 after 300 long cycles).

8.
ACS Appl Mater Interfaces ; 13(45): 54032-54042, 2021 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-34739216

RESUMEN

Looking for a high-efficiency, durabile, and low-cost dual-functional oxygen electrocatalyst as the air electrode catalyst in rechargeable zinc-air batteries (ZABs) is urgently desirable but faces many challenges. Herein, we propose the preparation strategy of effectively using a bifunctional electrocatalyst (Fe-Nx/C) based on the zeolite imidazole organic framework-8 (ZIF-8) as the template agent, with surface modification coated by ferrocene (Fc) molecules followed by pyrolysis at high temperature under inert atmosphere. Benefiting from the surface modification of ZIF-8 with Fc molecules, more abundant multiple catalytic Fe/Fe-Nx/FeCx sites with high intrinsic activity are derived, the resultant Fe-Nx/C exhibits excellent potential gap (ΔE = 0.63 V) and durability, which is obviously superior to the Pt/C + IrO2 benchmark (ΔE = 0.77 V) and other state-of-the-art electrocatalysts. Furthermore, the assembled rechargeable ZABs employing the Fe-Nx/C as an air-electrode show a reduced charging-discharging potential difference of 0.603 V, high power density of 214.8 mW cm-2, and long-term cycling stability of more than 290 h at 2.0 mA cm-2. Therefore, this work presents a feasible strategy to prepare a high-efficiency and durability ORR/OER bifunctional electrocatalyst toward high performance ZABs and next-generation energy storage devices.

9.
ACS Appl Mater Interfaces ; 13(28): 32968-32977, 2021 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-34227798

RESUMEN

Li2S-based Li-S batteries are taken as promising energy storage systems due to the high theoretical specific capacity/energy density and nature of a matching Li-metal-free anode. However, the cyclic stability of the Li2S-based Li-S battery is seriously prevented by the shuttle effect of lithium polysulfides (LiPSs). Meanwhile, due to the poor electrical conductivity of Li2S, the Li-S battery displays slow reaction kinetics. In this work, we design 3D-porous carbon (PC) architecture as a host for inhabiting the LiPS shuttle based on physical capture. Furthermore, this porous carbon architecture is modified by introducing two kinds of heteroatoms (N and S) to form dual active sites (named as NSPC) for chemically binding LiPSs and accelerating their conversion. The polyvinyl pyrrolidone-coated Li2SO4·H2O is embedded in the NSPC skeleton and further forms the Li2S/NSPC cathode via a carbothermal reduction process. In consequence, the NSPC architecture possesses continuous electron/ion channels and abundant active sites, which are beneficial to the fast diffusion of Li+ and timely conversion of sulfur species. As a result, the as-prepared Li2S/NSPC cathode exhibits a high initial discharge capacity of 690 mAh g-1 at a high rate of 1C and keeps a capacity of 587 mAh g-1 after 200 cycles with a good capacity retention rate of 85% and low fading rate of 0.075% per cycle. Therefore, this work offers a brand-new platform to understand the synergistic effects of promoting reaction kinetics for Li2S-based Li-S batteries.

10.
ACS Appl Mater Interfaces ; 13(24): 28324-28333, 2021 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-34106675

RESUMEN

Transition metal-nitrogen-carbon (TM-N-C) nanomaterials are promising platinum-based substitutes for the oxygen reduction reaction (ORR). However, large-scale commercial production of high-efficiency, durable TM-N-C catalysts remains a formidable challenge. In this work, a facile ″ZIF-on-ZIF″ strategy is first adopted to design ZIF-8@ZIF-67 core-shell polyhedral nanocages, and then, ferrocene (Fc) is added to form ZIF-8@ZIF-67@Fc double-layer encapsulating polyhedral nanocages. Finally, Zn, Co, and Fe tridoped N-C nanocages (ZnCoFe-N-C) as the high-efficiency ORR electrocatalyst are prepared through high-temperature annealing. Benefiting from the trimetal, nitrogen and carbon species bond to each other to form highly efficient active sites, and the material exhibits outstanding performance in 0.1 M KOH, onset potential and half-wave potential of up to 0.95 and 0.878 V (vs RHE), respectively, and long-term durability and methanol tolerance. Furthermore, when utilizing as a zinc-air battery (ZAB) air electrode, it exhibits wonderful indicators, reflected in an open circuit voltage of 1.525 V, power density of 350.2 mW cm-2, and specific capacity of 794.7 mAh gzn-1, which outperforms the benchmark Pt/C catalyst. This work provides a facile and effective strategy to obtain a highly efficient and stable TM-N-C electrocatalyst for the ORR in ZABs.

11.
Front Chem ; 8: 428, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32582631

RESUMEN

Doping heteroatom, an effective way to enhance the electrochemical performances of graphene, has received wide attention, especially related to nitrogen. Alternating voltage electrochemical exfoliation, as a low cost and green electrochemical approach, has been developed to construct in-situ N-doped graphene (N-Gh) material. The N-Gh presents a much higher capacity than that of pure graphene prepared via the same method, which might be attributed to the introduction of nitrogen, which has much more effects and a disordered structure. As-prepared N-Gh exhibits a low O/C ratio that is helpful in maintaining high electrical conductivity. And the effects and disorder structure are also conductive to reduce the overlaps of graphene layers. A symmetric supercapacitor assembled with N-Gh electrodes displays a satisfactory rate behavior and long cycling stability (92.3% retention after 5,000 cycles).

12.
Inorg Chem ; 58(9): 6410-6421, 2019 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-31009210

RESUMEN

Given its competitive theoretical capacity, Bi2MoO6 is deemed as a promising anode material for the realization of efficient Li storage. Considering the severe capacity attenuation caused by the lithiation-induced expansion, it is essential to introduce effective modification. Remarkably, in this work, Bi2MoO6 microsphere with double-layered spherical shells are successfully prepared, and the polyaniline are coated on both inner and outer surfaces of double-layered spherical shells, working as buffer layers to strain the volume expansion during electrochemical cycling. Inspiringly, when utilized as anode in LIBs, the specific capacity of Bi2MoO6@PANI is maintained at 656.3 mAh g-1 after 200 cycles at 100 mA g-1, corresponding to a high capacity of 82%. However, the counterpart of individual Bi2MoO6 is only 36%. This result confirms that the polyaniline layer can dramatically promote stable cycling performances. Supported by in situ EIS and ex situ technologies followed by detailed analysis, the enhanced pseudocapacitance-dominated contributions and electron/ion transfer rate, benefiting from the combination with polyaniline, are further proved. This work confirms the significant effect of polyaniline on the ultrastable energy storage, further providing an in-depth sight on the impacts of polyaniline coating to the electrical conductivity as well as the resistances of electron/ion transport.

13.
Data Brief ; 20: 790-793, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30211276

RESUMEN

The data presented in this data article are related to the research article entitled "Facile Synthetic Strategy to Uniform Cu9S5 Embedded into Carbon: A Novel Anode for Sodium-Ion Batteries" (Jing et al., 2018) [1]. The related experiment details of pure Cu9S5 has been stated. The structure data of pure Cu9S5 and the electrochemical performance for sodium-ion batteries are described.

14.
ACS Appl Mater Interfaces ; 9(31): 26118-26125, 2017 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-28723066

RESUMEN

Antimony represents a class of unique functional materials in sodium-ion batteries with high theoretical capacity (660 mA h g-1). The utilization of carbonaceous materials as a buffer layer has been considered an effective approach to alleviate rapid capacity fading. Herein, the antimony/nitrogen-doping porous carbon (Sb/NPC) composite with polyaniline nanosheets as a carbon source has been successfully achieved. In addition, our strategy involves three processes, a tunable organic polyreaction, a thermal annealing process, and a cost-effective reduction reaction. The as-prepared Sb/NPC electrode demonstrates a great reversible capacity of 529.6 mA h g-1 and an outstanding cycling stability with 97.2% capacity retention after 100 cycles at 100 mA g-1. Even at 1600 mA g-1, a superior rate capacity of 357 mA h g-1 can be retained. Those remarkable electrochemical performances can be ascribed to the introduction of a hierarchical porous NPC material to which tiny Sb nanoparticles of about 30 nm were well-wrapped to buffer volume expansion and improve conductivity.

15.
Org Lett ; 15(2): 354-7, 2013 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-23301922

RESUMEN

Two novel dendrimers, 16T and 20T, based on 1,1,2,2-tetra(thiophen-2-yl)ethene (4T) as a new dendron, were efficiently synthesized via carbonylation, Suzuki, and McMurry reactions. All intermediates and title compounds were fully characterized by (1)H NMR, (13)C NMR, and HRMS. 4T and 16T were confirmed by X-ray single crystal analyses. In addition, the absorption behaviors of two titled dendrimers are also described.

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