γ-Cyclodextrin-metal organic framework as a carrier for trans-N-p-coumaroyltyramine: A study of drug solubability, stability, and inhibitory activity against α-glucosidase.

γ-Cyclodextrin-based metal-organic frameworks (γ-CD-MOF) were successfully synthesized using the solvent diffusion method and applied as carriers for trans-N-p-coumaroyltyramine (N-p-t-CT, NCT) to study the solubability, stability, sustained release and inhibitory activity against α-glucosidase. The solubilization effect of γ-CD-MOF on N-p-t-CT was performed using impregnation (NCT@CD-MOF-1) and co-crystallization (NCT@CD-MOF-2) methods. X-ray diffraction, scanning electron microscope (SEM), fourier transform infrared spectrometer (FTIR), and N2 adsorption/desorption were used to characterize the MOFs before and after loading NCT. The results showed that NCT@CD-MOF-2 had a better solubability for N-p-t-CT, 145.03 µg/mg of drug loading capacity could be achieved, and the solubility of NCT@CD-MOF-2 in water was 366 times higher than free N-p-t-CT. In addition, the stabilities of N-p-t-CT under temperature, UV light and pH conditions were greatly improved after encapsulation in γ-CD-MOF. Furthermore, NCT@CD-MOFs had a sustained release of N-p-t-CT over an extended period in vitro due to the primary encapsulation in pore structures. Notably, γ-CD-MOF loaded with N-p-t-CT showed superior inhibitory activity against α-glucosidase compared to free N-p-t-CT. Cytotoxicity studies demonstrated that NCT@CD-MOF-2 had low toxicity in vitro and perfect biocompatibility with HL-7702 cells, and γ-CD-MOF could reduce the toxicity of free N-p-t-CT at higher concentrations.

Responses of plant and microbial C:N:P stoichiometry to livestock removal.

Livestock removal (LR) is considered an effective strategy for recovering ecosystem functions in degraded grasslands. Carbon (C), nitrogen (N), and phosphorus (P), as well as their ratios in plants and microorganisms, act as key regulators of ecosystem stability and nutrient limitation during grassland succession. However, few studies have comprehensively evaluated plant and microbial nutrient limitations through C:N:P stoichiometry following LR over different durations. Here, our study explored the contents of C, N, P contents, and C:N, C:P and N:P ratios of green and senescent leaves, microbial biomass and extracellular enzymes after 33 years of LR on the Loess Plateau, China. The results showed that LR increased the C, N, and P contents of plant and microbial communities. LR (>26 years) enhanced C, N, P contents of green leaves by 364.7 %, 232.2 %, 134.6 %, and C, N, P contents of senescent leaves by 164.8 %, 230.8 %, 86.3 %, respectively. LR also increased plant C:P and N:P ratios and the P reabsorption efficiency, indicating that the plant communities shifted from N to P-limitation during grassland restoration. Compared with the grazing sites, LR26 increased C, N, P contents, C:P and N:P ratios of soil microbial biomass, whereas reduced soil N-acquiring enzyme activity and enzymatic N:P ratio, indicating that the microbial community experienced higher P limitation than that of the grazing sites. Plant and microbial communities showed strong plastic relationships with soil resource. Vegetation cover and productivity played strong roles in altering the plant and microbial C:N:P stoichiometry following LR. These findings indicate that long-term LR (>26 years) will exacerbate plant and microbial P limitation during grassland succession.

Rhizosphere effects and microbial N limitations drive the root N limitations in the rhizosphere during secondary succession in a Pinus tabuliformis forest in North China.

Introduction: Rhizosphere effects (REs) have recently been identified as important regulators of root and microbial nutrient acquisition and are positively involved in nutrient cycling of belowground carbon (C), nitrogen (N), and phosphorus (P). Nutrient conditions of the fine roots and soil N are likely to influence REs. Still, it is unclear how REs of soil nutrients themselves variably impact the supply of nutrients to plants in terms of the responses to soil N due to succession. Methods: In this study, we applied both fine roots and extracellular enzymes for vector analysis and stoichiometry of N:P to explore the metabolic limitations of roots and rhizospheric soil microbes and their relationships with REs across five levels of soil N (0, 5, 10, 15, and 20 kg N m-2 year-1) along successional age classes of 42, 55, and 65 years in a Pinus tabuliformis forest. Results: Overall, the metabolism of root and rhizospheric soil microbes was mediated by soil N. N limitation of roots initially decreased before increasing, whereas that of microbes demonstrated opposite trends to the N levels owing to competition for inorganic N between them by REs of NO3 --N. However, N limitations of both roots and microbes were alleviated in young stands and increased with succession after the application of N. In addition, root N limitations were manipulated by REs of three different soil N-related indicators, i.e., total N, NH4 +-N, and NO3 --N. Rhizospheric soil microbial N limitation was almost unaffected by REs due to their strong homeostasis but was an important driver in the regulation of root N limitation. Discussion: Our results indicated that successional age was the most critical driver that directly and indirectly affected root N metabolism. However, the level of N application had a slight effect on root N limitation. Microbial N limitation and variations in the REs of N indicators regulated root N limitation in the rhizosphere. As a result, roots utilized REs to sequester N to alleviate N limitations. These findings contribute to novel mechanistic perspectives on the sustainability of N nutrition by regulating N cycling in a system of plant-soil-microbes in the rhizosphere to adapt to global N deposition or the heterogeneous distribution of bioavailable soil N with succession.

Detection of ciprofloxacin and pH by carbon dots and rapid, visual sensing analysis.

Food safety is a serious issue worldwide and practical detection method is vital for the supervision of food safety. It is necessary to establish efficient and economical methods to detect antibiotics, especially antibiotics in complex systems. This study employs citric acid and m-phenylenediamine to synthesize N, P-codoped carbon dots (N, P-CDs) by a microwave-assisted method. Anhydrous ethanol and phosphoric acid are essential to the properties of N, P-CDs. A "turn-on" fluorescent probe based on N, P-CDs was established for detecting ciprofloxacin (CIP) with detection limit down to 24.2 nm. Semiquantitative test stripe and a PS color detection system for CIP were developed to achieve visual and smart detection. The test stripe is applied to the visual detection of CIP residues in milk and a popular Chinese cuisine, Malatang, for the first time. N, P-CDs can also be used to detect pH in the range of pH 7.5-12.

In-situ synthesis of heteroatom-doped hard carbon for sodium-ion batteries: Dual benefits for green energy and environment.

Heteroatom-doped carbon has been widely investigated as anode materials for sodium-ion batteries (SIBs). However, simplifying the preparation process and precisely controlling their microstructure to achieve excellent Na+ storage performance remain significant challenges. Therefore, in this study, high-performance N, P co-doped Na+ storage carbon anode electrode materials were prepared by one-step carbonization using N, P-rich Eichhornia crassipes (EC) as raw materials and systematically tested for their Na+ storage performance. The doping levels of N and P atoms as well as the spatial structure of the carbon material were adjusted by changing the carbonization temperature during the pyrolysis process. Among them, the anode material corresponding to 1300 °C (EC-PN1300) showed an excellent Na+ storage capacity of 336 ± 4 mAh g-1 (50 mA g-1) and excellent cycling stability (99.8 % retention after 2000 cycles). In addition, the Na+ storage mechanism of EC-PN1300 was systematically analyzed using galvanostatic intermittent titration (GITT), ex-situ XPS and in-situ Raman spectroscopy, providing accurate research directions for developing carbon anode electrode materials with superior electrochemical performance. This study not only provides some insights into the preparation of carbon anode materials in alkali metal batteries and the development of carbon materials in other fields, but also realizes the interaction between environmental protection and new energy development.

Grazing period management affects the accumulation of plant functional groups, and soil nutrient pools and regulates stoichiometry in the desert steppe of Northwest China.

To understand how nutrient cycling and sequestration are influenced by different grazing periods, the C:N:P stoichiometry features of the plant-soil interface in the desert steppe were measured and evaluated. The 5-year seasonal grazing experiment employed four grazing period treatments: traditional time of grazing (TG), early termination of grazing (EG), delayed start of grazing (DG), and delayed start and early termination of grazing (DEG). Additionally, fenced off desert steppe served as the control. The grazing periods each had a differing impact on the C:N:P stoichiometry in both plant functional group and soil depth comparisons. Compared to the EG, DG, and DEG treatments, the TG treatment had a more significant impact on the C, N, and P pools of grass, as well as the C:P and N:P ratios of forbs, but had a reduced effect on the C:P and N:P ratios of legumes. In contrast to plants, the DG treatment exhibited greater advantages in increasing C pools within the 0-40 cm soil layer. Furthermore, in the 10-20 cm soil layer, the C:P and N:P ratios under the EG treatment were significantly higher, ranging from 8.88% to 53.41% and 72.34%-121.79%, respectively, compared to the other treatments (TG, DG, and DGE). The primary drivers of the C, N, and P pools during different grazing periods were above-ground biomass (AGB) and litter biomass (LB). Both lowering the plant C:P and N:P ratios and considerably raising the plant P pool during different grazing periods greatly weakened the P limitation of the desert steppe environment. It is predicted that delayed start grazing might be a management strategy for long-term ecosystem sustainability, as it regulates above-ground nutrient allocation and has a positive effect on soil C and N pools.

Highly active nitrogen-phosphorus co-doped carbon fiber@graphite felt electrode for high-performance vanadium redox flow battery.

Heteroatom-doped electrodes offer promising applications for enhancing the longevity and efficiency of vanadium redox flow battery (VRFB). Herein, we controllably synthesized N, P co-doped graphite fiber electrodes with conductive network structure by introducing protonic acid and combining electrodeposition and high temperature carbonization. H2SO4 and H3PO4 act as auxiliary and dopant, respectively. The synergistic effect between N and P introduces additional defect structures and active sites on the electrodes, thereby enhancing the reaction rate, as confirmed by density functional theory calculations. Furthermore, the conductive network structure of carbon fibers improves electrode-to-electrode connectivity and reduces internal battery resistance. The optimized integration of these strategies enhances VRFB performance significantly. Consequently, the N, P co-doped carbon fiber modified graphite felt electrodes demonstrate remarkably high energy efficiency at 200 mA cm-2, surpassing that of the blank battery by 7.9 %. This integrated approach to in-situ controllable synthesis provides innovative insights for developing high-performance, stable electrodes, thereby contributing to advancements in the field of energy storage.

Synergistic enhancement of Ni2P anode for high lithium/sodium storage by N, P, S triply-doping and soft template-assisted strategy.

Transition metal phosphides have demonstrated excellent performance in the field of energy conversion and storage, where nickel phosphide is one of the most prominent type of phosphides. However, achieving long cycle life with higher specific capacity in the case of Ni2P is still a great challenge. In this study, the composition and structure of Ni2P composites are rationally and precisely adjusted by heteroatoms doping and micelle-assisted methods to attain high capacity for longer cycles at high rate. Among all studied combinations, nickel phosphide particles anchored to triple heteroatom (N, P, S) doped carbon network skeleton (Ni2P@NPS) exhibited specific capacities of 727.3, 586.6, and 321.5 mA h g-1 after 1000 cycles at 1, 2 and 6 A g-1 for lithium-ion batteries (LIBs) and 230.1 mA h g-1 at 1 A g-1 for sodium-ion batteries (SIBs) after 560 cycles. The introduction of heteroatoms optimized the electronic structure of the electrode materials and promoted mass and charge transfer, while triple-heteroatom doped carbon substrates and uniformly dispersed spherical structures formed an active three-dimensional conductive network structure that provided a stronger driving force and richer channels for Li+/Na+ transport. Theoretical calculations showed that the high content of pyrrole nitrogen as well as the additional sulfur ensured improved electrical conductivity and enhanced ion adsorption performance. This study encourages further research into the synergistic effect of N, P, S co-doping materials for improving Li+/Na+ storage and the exploration of other heteroatom co-doping systems.

Nitrogen availability and summer drought, but not N:P imbalance, drive carbon use efficiency of a Mediterranean tree-grass ecosystem.

All ecosystems contain both sources and sinks for atmospheric carbon (C). A change in their balance of net and gross ecosystem carbon uptake, ecosystem-scale carbon use efficiency (CUEECO), is a change in their ability to buffer climate change. However, anthropogenic nitrogen (N) deposition is increasing N availability, potentially shifting terrestrial ecosystem stoichiometry towards phosphorus (P) limitation. Depending on how gross primary production (GPP, plants alone) and ecosystem respiration (RECO, plants and heterotrophs) are limited by N, P or associated changes in other biogeochemical cycles, CUEECO may change. Seasonally, CUEECO also varies as the multiple processes that control GPP and respiration and their limitations shift in time. We worked in a Mediterranean tree-grass ecosystem (locally called 'dehesa') characterized by mild, wet winters and summer droughts. We examined CUEECO from eddy covariance fluxes over 6 years under control, +N and + NP fertilized treatments on three timescales: annual, seasonal (determined by vegetation phenological phases) and 14-day aggregations. Finer aggregation allowed consideration of responses to specific patterns in vegetation activity and meteorological conditions. We predicted that CUEECO should be increased by wetter conditions, and successively by N and NP fertilization. Milder and wetter years with proportionally longer growing seasons increased CUEECO, as did N fertilization, regardless of whether P was added. Using a generalized additive model, whole ecosystem phenological status and water deficit indicators, which both varied with treatment, were the main determinants of 14-day differences in CUEECO. The direction of water effects depended on the timescale considered and occurred alongside treatment-dependent water depletion. Overall, future regional trends of longer dry summers may push these systems towards lower CUEECO.

Chromophoric dissolved organic matter traces seasonally changing coastal processes in a river-influenced region of the western Bay of Bengal.

The optical characteristics of colored dissolved organic matter (CDOM) serve as a convenient tool for evaluating coastal processes, e.g., river runoff, anthropogenic inputs, primary production, and bacterial/photochemical processes. We conducted a study on the seasonal and spatial variability of absorbance and fluorescence characteristics of CDOM and nutrients in the coastal waters near the Gauthami estuary of River Godavari, the largest peninsular river of India, for a year. The surface aCDOM(350) showed a significant inverse relation with salinity in the coastal region, indicating a conservative mixing of marine and terrestrial end members. The aCDOM(350) was not conservative in the offshore (100 m isobath) waters due to enrichment by secondary sources. Seasonal variability in optical properties indicated diverse sources for CDOM, as revealed by principal component analysis. The excitation-emission matrix (EEM) spectra followed by parallel factor analysis (EEM-PARAFAC) revealed four distinct fluorophores. The tyrosine (B) fluorophore showed a predominant increase in the post-monsoon season (October to January), while tryptophan (T) was relatively more enriched, coincident with nutrient enrichment and transparency increase during the early monsoon phase (July). The biological index (BIX), which reflects recent photosynthetic activity, also displayed relatively higher values during the early monsoon. The humic fluorophores A and M, and humification index (HIX) were relatively enriched during the later phase of monsoon (July-October). HIX was > 4 in a few samples of the offshore region (100-m isobath) and indicated a probable contamination from drill-mud (bentonite) used in hydrocarbon exploration. During the monsoon, the relationship between T and B with CDOM was not evident due to the masking of B fluorescence in intact protein. However, during the post-monsoon (POM) and pre-monsoon (PRM) periods, this masking effect was not observed, likely due to protein degradation via bacterial and photochemical processes, respectively. Temporal variability in nutrients indicated that high ammonium levels were produced during POM (OM bacterial degradation), and high nitrite levels were observed during PRM (due to primary production). This study provides foundational insights into the use of CDOM for understanding the impact of diverse environmental, river discharge, and anthropogenic factors on coastal ecosystems.

Modulation of Photocatalytic CO2 Reduction by n-p Codoping Engineering of Single-Atom Catalysts.

Transition metal (TM) single-atom catalysts (SACs) have been widely applied in photocatalytic CO2 reduction. In this work, n-p codoping engineering is introduced to account for the modulation of photocatalytic CO2 reduction on a two-dimensional (2D) bismuth-oxyhalide-based cathode by using first-principles calculation. n-p codoping is established via the Coulomb interactions between the negatively charged TM SACs and the positively charged Cl vacancy (VCl) in the dopant-defect pairs. Based on the formation energy of charged defects, neutral dopant-defect pairs for the Fe, Co, and Ni SACs (PTM0) and the -1e charge state of the Cu SAC-based pair (PCu-1) are stable. The electrostatic attraction of the n-p codoping strengthens the stability and solubility of TM SACs by neutralizing the oppositely charged VCl defect and TM dopant. The n-p codoping stabilizes the electron accumulation around the TM SACs. Accumulated electrons modify the d-orbital alignment and shift the d-band center toward the Fermi level, enhancing the reducing capacity of TM SACs based on the d-band theory. Besides the electrostatic attraction of the n-p codoping, the PCu-1 also accumulates additional electrons surrounding Cu SACs and forms a half-occupied dx2-y2 state, which further upshifts the d-band center and improves photocatalytic CO2 reduction. The metastability of Cl multivacancies limits the concentration of the n-p pairs with Cl multivacancies (PTM@nCl (n > 1)). Positively charged centers around the PTM@nCl (n > 1) hinders the CO2 reduction by shielding the charge transfer to the CO2 molecule.

[The Russian priority in development of general intravenous anesthesia (Report II)].

The article considers evaluation of works of colleagues and contemporaries of N. P. Kravkov, the creator of "Russian narcosis" with hedonal. The hidden and explicit, objective and subjective factors that prevented spreading of application of discovery of Russian scientists, both in Russia and abroad, are established. The dependence of self-esteem of Russian surgeons of XIX - early XX centuries on recognition of their scientific efforts in Germany is emphasized.

Trade-off between sulfidated zero-valent iron reactivity and air stability: Regulation of iron sulfides by ammonium dihydrogen phosphate.

The reactivity and stability of zero-valent iron (ZVI) and sulfidated zero-valent iron (S-ZVI) are inherently contradictory. Iron sulfides (FeSX) on the S-ZVI surface play multiple roles, including electrostatic adsorption and catalyzing reduction. We proposed to balance the reactivity and air stability of S-ZVI by regulating FeSX. Benefiting from the superior coordination and accelerate electron transport capabilities of phosphate, herein, eco-friendly ammonium dihydrogen phosphate (ADP) was employed to synthesize N, P, and S-incorporated ZVI (NPS-ZVI) and regulate the FeSX. Raman, FTIR, XPS, and density functional theory (DFT) calculations were combined to reveal that HPO42- acts as the main P species on the Fe surface. The superior reactivity of NPS-ZVI was quantified by kobs, kSA, and kM of Cr(VI), which were 210.77, 27.44, and 211.17-fold than ZVI, respectively. NPS-ZVI demonstrated excellent reusability, with no risk of secondary pollution. Critically, NPS-ZVI could effectively maintain FeSX stability under the combination of diffusion limitation and surface protection mechanisms of ADP. The superior reactivity of NPS-ZVI was attributed to the fact that ADP maintains FeSX stability and accelerates electron transport. This study provides a novel strategy in balancing the reactivity and air stability of S-ZVI and offers theoretical support for material modification.

The Preparation of N, P-Doped NiSe Nanorod Electrode Materials on Nickel Foam Using the Microwave Method for High-Performance Supercapacitors.

Transition metal selenides have the leading position in the field of energy storage and conversion due to their high theoretical capacity, good electrical conductivity, and cycling stability. Nickel is widely used for the construction of positive electrodes in devices due to its good conductivity, variable valence state, and ideal redox activity. NiSe materials have high internal resistance and are prone to volume change during charging and discharging, thus affecting the practical application of this electrode material, and the reported NiSe materials have not achieved a more desirable capacity value. Therefore, in this study, N, P-NiSe nanoelectrode materials were prepared using nickel foam as the nickel source and hexachlorocyclotriphonitrile as the nitrogen and phosphorus dopant using an efficient, energy-saving, and simple microwave method. It was also characterised by XRD and XPS to confirm the successful preparation of N, P-NiSe materials. In addition, the material yielded a high capacitance value (3184 F g-1) and good cycling stability (72% of the initial capacitance value was retained after 4000 cycles) in electrochemical tests. To demonstrate its excellent suitability for practical applications, an asymmetric supercapacitor was assembled using N, P-NiSe as the anode and activated carbon as the cathode. At an operating voltage of 1.6 V, the device achieved an energy density of 289.06 Wh kg-1 and a power density of 799.26 W kg-1 and retained 80% of its initial capacity after 20,000 cycles.

Chlorophyll fluorescence characteristics and H2O2 contents of Chinese tallow tree are dependent on population origin, nutrients and salinity.

Plants from invasive populations often have higher growth rates than conspecifics from native populations due to better environmental adaptability. However, the roles of improved chlorophyll fluorescence or antioxidant defenses in helping them to grow better under adverse situations are insufficient, even though this is a key physiological question for elucidating mechanisms of plant invasion. Here, we conducted experiments with eight native (China) and eight introduced (USA) populations of Chinese tallow tree (Triadica sebifera). We tested how salinity, nutrients (overall amount or N:P in two separate experiments) and their interaction affected T. sebifera aboveground biomass, leaf area, chlorophyll fluorescence and antioxidant defenses. Plants from introduced populations were larger than those from native populations, but salinity and nutrient shortage (low nutrients or high N:P) reduced this advantage, possibly reflecting differences in chlorophyll fluorescence based on their higher PSII maximum photochemical efficiency (F v/F m) and PSI maximum photo-oxidizable P700 in higher nutrient conditions. Native population plants had lower F v/F m with saline. Except in high nutrients/N:P with salinity, introduced population plants had lower electron transfer rate and photochemical quantum yield. There were no differences in antioxidant defenses between introduced and native populations except accumulation of hydrogen peroxide (H2O2), which was lower for introduced populations. Low nutrients and higher N:P or salinity increased total antioxidant capacity and H2O2. Our results indicate that nutrients and salinity induce differences in H2O2 contents and chlorophyll fluorescence characteristics between introduced and native populations of an invasive plant, illuminating adaptive mechanisms using photosynthetic physiological descriptors in order to predict invasions.

Unlocking the critical roles of N, P Co-Doping in MXene for Lithium-Oxygen Batteries: Elevated d-Band center and expanded interlayer spacing.

The design and fabrication of bifunctional catalysts with high electrocatalytic activity and stability are critical for developing highly reversible Li-O2 batteries (LOBs). Herein, the N, P co-doped MXene (NP-MXene) is prepared by one-step annealing method and evaluated as bifunctional catalyst for LOBs. The results suggest that the P doping plays a crucial role in increasing interlayer distance of MXene, thereby effectively providing more active sites, fast mass transfer, and ample space for the deposition/decomposition of Li2O2. Moreover, the N doping can significantly elevate the d-band center of Ti, thereby remarkably improving the adsorption of reaction intermediates and accelerating the deposition/decomposition of Li2O2 films. Consequently, the MXene-based LOBs deliver an ultrahigh specific capacity of 13,995 mAh/g at 500 mA g-1, a discharge/charge voltage gap of 0.89 V, and a cycle life up to 523 cycles with a limited capacity of 1000 mAh/g at 500 mA g-1. Impressively, the as-fabricated flexible LOBs with NP-MXene cathode display excellent cycling stability and ability to continuously power LEDs even after bending. Our findings pave the road of heteroatom doped MXenes as next-generation electrodes for high-performance energy storage and conversion systems.

[Effects of N, P, and K application rates on distribution of 13C assimilates, starch accumulation in grains and fertilizer utilization of wheat]. / 氮磷钾施用量对小麦旗叶13CåŒåŒ–ç‰©åˆ†é ã€ç±½ç²’æ·€ç²‰ç§¯ç´¯å’Œè‚¥æ–™åˆ©ç”¨çš„å½±å“.

Clarifying the appropriate application rates of N, P, and K fertilizers and the physiological mechanisms of wheat under water-saving recharge irrigation in the North China Plain would provide a theoretical basis for formulating reasonable fertilization plans for high-yield and high-efficiency wheat production. We established four treatments with different amounts of nitrogen (N), phosphorus (P2O5), and potassium (K2O) application: 0, 0, and 0 kg·hm-2 (F0), 180, 75, and 60 kg·hm-2 (F1), 225, 120, and 105 kg·hm-2 (F2), and 270, 165, and 150 kg·hm-2 (F3). During the jointing and anthesis stages of wheat, the relative water content of each treatment in the 0-40 cm soil layer was replenished to 70%, to investigate the differences in wheat flag leaf photosynthetic characteristics, distribution of 13C assimilates, grain starch accumulation, and fertilizer utilization. The results showed that the relative chlorophyll content of flag leaves, photosynthetic and chlorophyll fluorescence parameters, 13C assimilate allocation in each organ, enzyme activities involved in starch synthesis, and starch accumulation in the F1 treatment were significantly higher than that in F0 treatment, which was an important physiological basis for the 20.9% increase in grain yield. The above parameters and yield in the F2 and F3 treatments showed no significant increase compared to F1 treatment, while fertilizer productivity and agronomic efficiency of N, P, and K decreased by 17.5%-58.4% and 12.7%-50.7%, respectively. Therefore, F1 could promote flag leaf photosynthetic assimilate production and grain starch accumulation under water-saving supplementary irrigation conditions, resulting in higher grain yield and fertilizer utilization efficiency.

N-P covalent bond regulation of mesoporous carbon-based catalyst for lowered oxygen reduction overpotential and enhanced zinc-air battery performance.

Developing sustainable metal-free carbon-based electrocatalysts is essential for the deployment of metal-air batteries such as zinc-air batteries (ZABs), among which doping of heteroatoms has attracted tremendous interest over the past decade. However, the effect of the heteroatom covalent bonds in carbon matrix on catalysis was neglected in most studies. Here, an efficient metal-free oxygen reduction reaction (ORR) catalyst is demonstrated by the N-P bonds anchored carbon (termed N,P-C-1000). The N,P-C-1000 catalyst exhibits superior specific surface area of 1362 m2 g-1 and ORR activity with a half-wave potential of 0.83 V, close to that of 20 wt% Pt/C. Theoretical computations reveal that the p-band center for C-2p orbit in N,P-C-1000 has higher interaction strength with the intermediates, thus reducing the overall reaction energy barrier. The N,P-C-1000 assembled primary ZAB can attain a large peak power density of 121.9 mW cm-2 and a steady discharge platform of ∼1.20 V throughout 120 h. Besides, when served as the cathodic catalyst in a solid-state ZAB, the battery shows flexibility, conspicuous open circuit potential (1.423 V), and high peak power density (85.8 mW cm-2). Our findings offer a strategy to tune the intrinsic structure of carbon-based catalysts for improved electrocatalytic performance and shed light on future catalysts design for energy storage technologies beyond batteries.

Molecule Engineering of Sugar Derivatives as Electrolyte Additives for Deep-Reversible Zn Metal Anode.

The cycling performance of zinc-ion batteries is greatly affected by dendrite formation and side reactions on zinc anode, particularly in scenarios involving high depth of discharge (DOD) and low negative/positive capacity (N/P) ratios in full cells. Herein, drawing upon principles of host-guest interaction chemistry, we investigate the impact of molecular structure of electrolyte additives, specifically the -COOH and -OH groups, on the zinc negative electrode through molecular design. Our findings reveal that molecules containing these groups exhibit strong adsorption onto zinc anode surfaces and chelate with Zn2+, forming a H2O-poor inner Helmholtz plane. This effectively suppresses side reactions and promotes dendrite-free zinc deposition of exposed (002) facets, enhancing stability and reversibility of an average coulombic efficiency of 99.89 % with the introduction of Lactobionic acid (LA) additive. Under harsh conditions of 92 % DOD, Zn//Zn cells exhibit stable cycling at challenging current densities of 15 mA ⋅ cm-2. Even at a low N/P ratio of 1.3, Zn//NH4V4O10 full cells with LA electrolyte exhibit high-capacity retention of 73 % after 300 cycles, significantly surpassing that of the blank electrolyte. Moreover, in a conversion type Zn//Br static battery with a high areal capacity (~5 mAh ⋅ cm-2), LA electrolyte sustains an improved cycling stability of 700 cycles.

Phycospheric bacteria limits the effect of nitrogen and phosphorus imbalance on diatom bloom.

Human activities have caused an imbalance in the input nitrogen and phosphorus (N/P) in the biosphere. The imbalance of N/P is one of the characteristics of water eutrophication, which is the fundamental factor responsible for the blooms. The effects of the N/P imbalance on diatom and phycospheric bacteria in blooms are poorly understood. In this study, the N/P molar ratio in real water (14:1) and the predicted N/P molar ratio in future water (65:1) were simulated to analyze the response of Cyclotella sp. and phycospheric bacteria to the N/P imbalance. The results showed that the N/P imbalance inhibited the growth of Cyclotella sp., but prolonged diatom bloom duration. The resistance of Cyclotella sp. to the N/P imbalance is related to phycospheric bacteria, and there are dynamic regulatory mechanisms within the phycospheric bacteria community to resist the N/P imbalance: (1) the increase of HNA bacterial density, the decrease of LNA bacterial density, (2) the increase of phycospheric bacterial diversity and eutrophic bacteria abundance, and the change of denitrifying bacteria abundance, (3) the activity of nitrogen and phosphorus metabolism of HNA bacteria enhanced, while that of LNA bacteria decreased. And the gene hosts of nitrogen and phosphorus metabolism were most enriched in Proteobacteria, indicating that Proteobacteria played an important role in maintaining the stability of phycospheric bacteria and was the dominant phylum resistant to the N/P imbalance. This study clarified that the algal-bacteria system was resistant to the N/P imbalance and implied that the N/P imbalance had little effect on the occurrence of diatom bloom events due to the presence of phycospheric bacteria.