It is still very urgent and challenging to simultaneously develop high‐rate and long‐cycle oxide cathodes for sodium‐ion batteries (SIBs) because of the sluggish kinetics and complex multiphase ...evolution during cycling. Here, the concept of accurately manipulating structural evolution and formulating high‐performance heterostructured biphasic layered oxide cathodes by local chemistry and orbital hybridization modulation is reported. The P2‐structure stoichiometric composition of the cathode material shows a layered P2‐ and O3‐type heterostructure that is explicitly evidenced by various macroscale and atomic‐scale techniques. Surprisingly, the heterostructured cathode displays excellent rate performance, remarkable cycling stability (capacity retention of 82.16% after 600 cycles at 2 C), and outstanding compatibility with hard carbon anode because of the integrated advantages of intergrowth structure and local environment regulation. Meanwhile, the formation process from precursors during calcination and the highly reversible dynamic structural evolution during the Na+ intercalation/deintercalation process are clearly articulated by a series of in situ characterization techniques. Also, the intrinsic structural properties and corresponding electrochemical behavior are further elucidated by the density of states and electron localization function of density functional theory calculations. Overall, this strategy, which finely tunes the local chemistry and orbitals hybridization for high‐performance SIBs, will open up a new field for other materials.
An abnormal heterostructured biphasic layered oxide cathode for sodium‐ion batteries (SIBs) is successfully constructed, and its dynamic formation process, intrinsic structural properties, and electrochemical behavior are elucidated by a series of in situ characterization techniques and density functional theory calculations. The concept of accurately manipulating structural evolution and formulating heterostructured cathode materials by local chemistry and orbital hybridization modulation is further demonstrated.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Summary
The continuing nitrogen (N) deposition observed worldwide alters ecosystem nutrient cycling and ecosystem functioning. Litter decomposition is a key process contributing to these changes, but ...the numerous mechanisms for altered decomposition remain poorly identified.
We assessed these different mechanisms with a decomposition experiment using litter from four abundant species (Achnatherum sibiricum, Agropyron cristatum, Leymus chinensis and Stipa grandis) and litter mixtures representing treatment‐specific community composition in a semi‐arid grassland under long‐term simulation of six different rates of N deposition.
Decomposition increased consistently with increasing rates of N addition in all litter types. Higher soil manganese (Mn) availability, which apparently was a consequence of N addition‐induced lower soil pH, was the most important factor for faster decomposition. Soil C : N ratios were lower with N addition that subsequently led to markedly higher bacterial to fungal ratios, which also stimulated litter decomposition.
Several factors contributed jointly to higher rates of litter decomposition in response to N deposition. Shifts in plant species composition and litter quality played a minor role compared to N‐driven reductions in soil pH and C : N, which increased soil Mn availability and altered microbial community structure. The soil‐driven effect on decomposition reported here may have long‐lasting impacts on nutrient cycling, soil organic matter dynamics and ecosystem functioning.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Optimizing charge transfer and alleviating volume expansion in electrode materials are critical to maximize electrochemical performance for energy storage systems. Herein, an atomically thin ...soft-rigid Co
S
@MoS
core-shell heterostructure with dual cation vacancies at the atomic interface is constructed as a promising anode for high-performance sodium-ion batteries. The dual cation vacancies involving V
and V
in the heterostructure and the soft MoS
shell afford ionic pathways for rapid charge transfer, as well as the rigid Co
S
core acts as the dominant active component and resists structural deformation during charge/discharge. Electrochemical testing and theoretical calculations demonstrate both excellent Na
transfer kinetics and pseudocapacitive behavior. Consequently, the soft-rigid heterostructure delivers extraordinary sodium storage performance (389.7 mA h g
after 500 cycles at 5.0 A g
), superior to those of the single-phase counterparts; and the assembled Na
V
(PO
)
||d-Co
S
@MoS
/S-Gr full cell achieves an energy density of 235.5 Wh kg
at 0.5 C. Our finding opens up a new strategy of soft-rigid heterostructure and broadens the horizons of material design in energy storage and conversion. This article is protected by copyright. All rights reserved.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Sodium‐ion oxide cathodes with triphase heterostructures have attracted intensive attention, since the sodium‐storage performance can be enhanced by utilizing the synergistic effect of different ...phases. However, the composite structures generally suffer from multiple irreversible phase transitions and high lattice strain because of interlayer‐gliding during the charge/discharge process. Here, the concept of strain engineering via manipulating the local chemistry of heterostructured oxide cathode is proposed to regulate the relevant physical and chemical properties, resulting in highly reversible structural evolution (P2/P3/spinel → P2/P3″/spinel) and low intrinsic stress in the potential window of 1.5–4.0 V. Also, the simple structural evolution at a relatively high cut‐off potential of 4.3 V can be detected by in situ X‐ray diffraction and other electrochemical characterization techniques during Na+ extraction/insertion. Meanwhile, the electrode exhibits a high reversible capacity (169.4 mAh g−1 at 0.2 C) and excellent rate performance from 1.5 to 4.3 V. Overall, this study reveals the mechanisms of regulating local chemistry to realize strain engineering of the cathode materials and paves the way for the further improvement of high‐performance sodium‐ion batteries.
Strain engineering by manipulating the local chemistry of a heterostructured oxide cathode can facilitate phase transformation and suppress lattice strain, resulting in high‐performance sodium‐ion batteries. The concept of local chemistry modulation can also be used to regulate the physical and chemical properties of other electrode materials and further inspire the exploitation of new materials and chemistries in energy storage and conversion.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Layered transition metal oxide (NaxTMO2), being one of the most promising cathode candidates for sodium‐ion batteries (SIBs), have attracted intensive interest because of their nontoxicity, high ...theoretical capacities, and easy manufacturability. However, their physical and electrochemical properties of water sensitivity, sluggish Na+ transport kinetics, and irreversible multiple‐phase translations hinder the practical application. Here, a concept of surface lattice‐matched engineering is proposed based on in situ spinel interfacial reconstruction to design a spinel coating P2/P3 heterostructure cathode material with enhanced air stability, rate, and cycle performance. The novel structure and its formation process are verified by transmission electron microscopy and in situ high‐temperature X‐ray diffraction. The electrode exhibits an excellent rate performance with the highly reversible phase transformation demonstrated by in situ charging/discharging X‐ray diffraction. Additionally, even after a rigorous water sensitivity test, the electrode materials still retain almost the same superior electrochemical performance as the fresh sample. The results show that the surface spinel phase can play a vital role in preventing the ingress of water molecules, improving transport kinetics, and enhancing structural integrity for NaxTMO2 cathodes. The concept of surface lattice‐matched engineering based on in situ spinel interfacial reconstruction will be helpful for designing new ultra‐stable cathode materials for high‐performance SIBs.
The formation process and function mechanism for inhibiting phase transformation and enhancing air stability of surface lattice‐matched engineering based on in situ spinel interfacial reconstruction are studied. This strategy of designing heterostructure with in situ interfacial reconstruction will inspire the exploitation of new chemistries and materials.
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Elevated levels of neutrophils have been associated with poor survival in various cancers, but direct evidence supporting a role for neutrophils in the immunopathogenesis of human cancers is lacking.
...A total of 573 patients with gastric cancer were enrolled in this study. Immunohistochemistry and real-time PCR were performed to analyze the distribution and clinical relevance of neutrophils in different microanatomic regions. The regulation and function of neutrophils were assessed both
and
Increased neutrophil counts in the peripheral blood were associated with poor prognosis in gastric cancer patients. In gastric cancer tissues, neutrophils were enriched predominantly in the invasive margin, and neutrophil levels were a powerful predictor of poor survival in patients with gastric cancer. IL17
neutrophils constitute a large portion of IL17-producing cells in human gastric cancer. Proinflammatory IL17 is a critical mediator of the recruitment of neutrophils into the invasive margin by CXC chemokines. Moreover, neutrophils at the invasive margin were a major source of matrix metalloproteinase-9, a secreted protein that stimulates proangiogenic activity in gastric cancer cells. Accordingly, high levels of infiltrated neutrophils at the invasive margin were positively correlated with angiogenesis progression in patients with gastric cancer.
These data provide direct evidence supporting the pivotal role of neutrophils in gastric cancer progression and reveal a novel immune escape mechanism involving fine-tuned collaborative action between cancer cells and immune cells in the distinct tumor microenvironment.
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•Denitrifying-anammox sludge was shown to be a promising alternative for the inoculum.•The anammox reactor was successfully started up within 40days.•Evolution of the bacterial ...community was monitored.•Conductivity was used as an indicator to track the start-up process.
Successful start-up of the anaerobic ammonium oxidation (anammox) process in up-flow sludge blanket reactor was achieved by seeding denitrifying (R0) or mixed denitrifying-anammox granular sludge at a 3:1 volume ratio (R1). The results demonstrated that R1 was successfully started-up on day 40 and had a nitrogen removal rate (NRR) of 0.55kgNm−3d−1. By contrast, it took 98days to start up R0 (0.54kgNm−3d−1). R0 and R1 achieved maximum NRRs of 5.70 and 12.02kgNm−3d−1, respectively. The biogranules from R1 generally possessed greater specific anammox activity (SAA), higher extracellular polymeric substance (EPS) and heme c content, larger granules and greater settling velocity. Quantitative PCR (qPCR) and high-throughput sequencing techniques were used to monitor the evolution of the bacterial community. These results demonstrated the feasibility of seeding mixed denitrifying-anammox granular sludge to start-up an anammox reactor.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Pd-catalyzed C–H functionalizations promoted by transient directing groups remain largely limited to C–H arylation only. Herein, we report a diverse set of ortho-C(sp2)–H functionalizations of ...benzaldehyde substrates using the transient directing group strategy. Without installing any auxiliary directing group, Pd(II)-catalyzed C–H arylation, chlorination, bromination, and Ir(III)-catalyzed amidation, could be achieved on benzaldehyde substrates. The transient directing groups formed in situ via imine linkage can override other coordinating functional groups capable of directing C–H activation or catalyst poisoning, significantly expanding the scope for metal-catalyzed C–H functionalization of benzaldehydes. The utility of this approach is demonstrated through multiple applications, including late-stage diversification of a drug analogue.
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IJS, KILJ, NUK, PNG, UL, UM
Acute lymphoblastic leukemia (ALL) is the most common malignancy among children. The trial Chinese Children Leukemia Group (CCLG)‐ALL 2008 was a prospective clinical trial designed to improve ...treatment outcome of childhood ALL through the first nation‐wide collaborative study in China. Totally 2231 patients were recruited from ten tertiary hospitals in eight cities. The patients were stratified according to clinical‐biological characteristics and early treatment response. Standard risk (SR) and intermediate risk (IR) groups were treated with a modified BFM based protocol, and there was 25%‐50% dose reduction during intensification phases in the SR group. Patients in high risk (HR) group received a more intensive maintenance treatment. Minimal residual disease (MRD) monitoring with treatment adjustment was performed in two hospitals (the MRD group). Complete remission (CR) was achieved in 2100 patients (94.1%). At five years, the estimate for overall survival (OS) and event‐free survival (EFS) of the whole group was 85.3% and 79.9%, respectively. The cumulative incidence of relapse (CIR) was 15.3% at five years. The OS, EFS and CIR for the SR group were 91.5%, 87.9%, and 9.7%, respectively. The outcome of the MRD group is better than the non‐MRD group (5y‐EFS: 82.4% vs 78.3%, P = .038; 5y‐CIR: 10.7% vs 18.0%, P < .001). Our results demonstrated that the large‐scale multicenter trial for pediatric ALL was feasible in China. Dose reduction in the SR group could achieve high EFS. MRD‐based risk stratification might improve the treatment outcome for childhood ALL.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The efficiency of the ultraviolet (UV)/chlorine process strongly depends on UV wavelength because chlorine photolysis and its subsequent radical formation are highly wavelength-dependent. This study ...compared the degradation of humic acid (HA) during the UV/chlorine process by low pressure mercury lamp (LPUV, 254 nm) and ultraviolet light-emitting diode (UV-LED, 275 and 310 nm). The results indicated that HA degradation followed the pseudo-first-order kinetics, and the fluence-based degradation rate constants (kobs) were significantly affected by UV wavelength and solution pH. HA degradation decreased greatly with increasing solution pH during the UV/chlorine process at 254 nm, while the opposite trend was observed at 275 and 310 nm. In the meantime, kobs decreased in the order of 275 nm > 254 nm > 310 nm at pH > 7.0. The changes of chlorine molar absorption coefficients at different UV wavelengths resulted in the variation of chlorine photodecay rates (kobs, chlorine), and the synergistic effects of kobs, chlorine and chlorine quantum yields (Φchlorine) affected HA reduction. The formation of disinfection by-products (DBPs) during the UV/chlorine process was also evaluated. A significant suppression on DBP formation and DBP-associated calculated theoretical cytotoxicity were observed at 275 nm high UV fluence and alkaline pHs. These findings in this study demonstrate that UV wavelength at 275 nm is more suitable for HA degradation by the UV/chlorine advanced oxidation process in practical applications.
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•HA degradation rate constants were significantly affected by UV wavelength in the UV/chlorine process.•The UV/chlorine process was more efficient at 275 nm than 254 and 310 nm at alkaline conditions.•Effective mitigation of DBPs and toxicity was achieved at 275 nm at high UV fluence.•DBP-associated cytotoxicity decreased in the order of 254 > 310 > 275 nm at high UV fluence in the presence of Br−.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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