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Porous photonic structures have greatly advanced large‐scale radiative cooling application owing to its satisfying optical properties, easy‐designation, and low cost. However, current reported porous radiative cooling materials mainly focuses on uniform or random pore distribution structure, which failed to achieve precise spectrum control for sunlight and mid‐infrared light, thereby weakening the radiative cooling performance. Herein, gradient structural porous metamaterials (GSPMs) are proposed and successfully constructed for maximizing cooling effectiveness based on step‐by‐step freeze‐casting technology. The designed GSPMs with gradient micro‐nano porous structure can wide‐range scatter entire solar spectrum while possess gradual refractive index transition to increase air‐medium interface absorption at mid‐infrared regions. Notably, solar reflectivity and mid‐infrared emissivity of GSPMs reach 97.3% and 97.6%, achieving maxinum cooling temperature of 8.7 °C and net cooling power of 94.1 W m−2, presenting a higher cooling effect than random porous materials. Moreover, GSPMs enable achieve compatibility with color aesthetic and cooling superiorities due to selective spectra response behavior, as well as can be applied in building materials, realizing efficient energy saving and CO2 emission reduction. This work proposed gradient porous structure can achieve highly efficient daytime radiative cooling, offering new possibilities in the structure design of next‐generation porous radiative cooling materials. [ABSTRACT FROM AUTHOR]

Ungulate grazing involves multiple components, including defoliation, dung and urine return, and trampling, which supply offsetting or synergistic effects on plant community composition and productivity (ANPP), but these effects have not been fully studied. Plant functional traits may reflect the response of plants to disturbance and their impact on ecosystem functions. Species turnover and intraspecific trait variation (ITV) are important drivers of community trait composition. We conducted a simulated grazing experiment in a steppe grassland in northern China to examine the effects of defoliation, dung and urine return, and trampling on community-weighted mean (CWM), functional diversity (FD) and ANPP, and to disentangle the roles of species turnover and ITV in driving these changes. We found that defoliation had a dominant effect on CWMs and FDs of all four traits through species turnover and ITV, respectively, resulting in a convergence of traits towards as more resource-acquisitive strategy. Dung-urine return resulted in more resource-acquisitive community traits mainly through ITV, whereas there were no significant effects on FDs except for leaf C/N. Trampling increased CWM of leaf dry matter content primarily driven by ITV, and had no significant effect on FDs. Furthermore, our simulated grazing positively affected ANPP, primarily due to nutrient additions from dung and urine, and ITV largely explained the variation in ANPP. These findings highlight the multifaceted effects of grazing components on community structure and ANPP, and the significance of ITV in shaping grassland plant communities and productivity. [ABSTRACT FROM AUTHOR]

Mixing of reagents in microfluidics is critical, and currently, the focus is on Newtonian fluids, but these reagents are often viscoelastic fluids. In this study, a micromixer containing a conductive cylinder is proposed based on the principle of induced charge electro-osmosis (ICEO). The Oldroyd-B constitutive model was chosen to characterize the flow properties of viscoelastic fluids, and the Poisson–Boltzmann model was used to describe the ion distribution in the electrolyte. The impact of the elasticity number (El) of viscoelastic fluids on the mixing efficiency, velocity, and vortex in the micromixer was studied. The results show that the mixing efficiency is only 55.41% when El = 0 (Newtonian fluid), and the mixing efficiency reaches 99.08% when El = 50. As El increases from 0 to 50, the cross-sectional average velocity at 50 μm from the micromixer exit decreases from 160 to 26.1 μm/s. Furthermore, the vortices around the conductive plate generated by the ICEO phenomenon begin to fluctuate at El = 7. [ABSTRACT FROM AUTHOR]

Micromixers have important applications in lab-on-a-chip, biomanufacturing, and chemical engineering. In this study, a micromixer with a conductive barrier plate based on the induced charge electro-osmosis is proposed. The Oldroyd-B constitutive model was chosen to characterize the flow characteristics of viscoelastic fluids, and the Poisson–Boltzmann model was used to characterize the electrokinetic properties. The effects of the installation of the conductive plate, the concentration of the polymer, and the shape of the conductive plate on the mixing were studied based on the finite volume method. The mixing efficiency of the viscoelastic fluids is 78.3% when a non-conductive plate is placed in the micromixer. However, placing a conductive plate increases the mixing efficiency to 89.8%. As the polymer concentration increases, the mixing efficiency increases, which is attributed to the elastic instability. As the curvature of the conductive plate increases from 0° to 360°, the mixing efficiency of the Newtonian fluid increases by 2.82%, while that of the polyacrylamide solutions at concentrations of 100 and 250 ppm increases by 5.31% and 1.97%, respectively. [ABSTRACT FROM AUTHOR]

Plant carbon (C) input via litter decomposition is essential for forming soil organic C (SOC). Previous studies have investigated the fate of litter C through one-time litter addition, while litter input could be recurrent, e.g., gradual litter input from above-ground plant material in diverse ecosystems. This paper investigates how litter input's frequency (single vs. repeated) and amount (low vs. high) affect the SOC formation and the associated microbial community composition and activity in a controlled microcosm experiment. After incubating the 13C-labeled litter (Stipa krilovii) for 80 days with the fresh field soil collected from a semi-arid steppe in Inner Mongolia, China, we measured newly formed SOC, microbial biomass C (MBC), and microbial phospholipid fatty acid (PLFA) indicated by 13C-labeling. The repeated litter addition resulted in 19.92% greater and 12.45% more efficient SOC formation than the single addition. Repeated litter addition also increased C use efficiency (CUE, + 76.71%), indicating more substrate C allocated for microbial growth than respiration. It also enhanced the fungi to bacteria ratio by 47.40% (based on 13C-PLFA) and maintained relatively stable microbial assimilation of litter C (based on 13C-MBC). These findings were consistent regardless of litter amounts. Our results indicate that the uninterrupted litter input to the soil in natural ecosystems benefits SOC formation and highlights soil fungi's critical role in promoting SOC formation. This study suggests that incorporating plant C input frequency into SOC dynamic models may improve the predictions of C cycling. [ABSTRACT FROM AUTHOR]

Soil microorganisms play a key role in the provision of plant-bioavailable nutrients, which is crucial for ecosystem functioning and plant productivity. Fairy rings are widespread features in grasslands accompanied by lush dark-green vegetation bands. This enigmatic feature is caused by increased soil bioavailable nitrogen (N) due to the expansion of fairy ring fungi (FRF). However, little is known about how FRF enhance soil bioavailable N concentrations. Here, we conducted a survey of 35 fairy rings in temperate grasslands to reveal the role of FRF in regulating soil microorganisms and N cycling using amplicon and metagenomic sequencing. The presence of FRF accelerated organic N mineralization via promoting extracellular enzyme (β-1,4- N -acetylglucosaminidase) activity, leading to a 455% increase in ammonium-N. This further stimulated nitrification to enhance nitrate-N concentration by favoring ammonia-oxidizing archaea. Concomitantly, the increased nitrate-N did not promote denitrification or affect the potential risk of N loss. Furthermore, the relative abundance of other saprotrophic and symbiotrophic fungi was significantly reduced by FRF but the changes in these fungi did not affect the activity of extracellular enzymes involved in N mineralization. Our results suggest that FRF can act as ecosystem engineer species shaping fairy rings by driving soil N cycling without the involvement of other microbial functional groups of saprotroph and symbiotroph to boost plant productivity. Thus, due to the stronger N mobilizing ability, FRF show great potential to be exploited as beneficial microorganisms in plant production and sustainable agricultural development. [Display omitted] ● Fairy ring fungi act as ecosystem engineers that drive soil bioavailable nitrogen dynamics to boost plant productivity. ● The presence of fairy ring fungi accelerates organic nitrogen mineralization and nitrification to accumulate bioavailable nitrogen. ● Fairy ring fungi temporarily dominate soil fungal communities and substantially affect microbial functions. [ABSTRACT FROM AUTHOR]

Soil aggregation and its stability are fundamental in ensuring soil function and ecosystem service provision, which can be greatly altered by ungulate disturbance, particularly the indirect effects from biomass removal by defoliation and direct effects from hoof trampling, but the mechanisms underlying the effect of defoliation and trampling on soil aggregation remains largely unexplored. Here, we conducted a 3-year manipulative experiment to investigate the effects of defoliation and trampling of ungulates and their interaction on soil aggregate stability in a semiarid grassland of Inner Mongolia, China. We found that defoliation rather than trampling dominantly affected soil aggregate stability. Defoliation disintegrated macroaggregates, reducing aggregate stability (-5 %), mainly attributed to the direct influence of a decline in plant inputs (aboveground biomass: −32 %) and the indirect effects of soil microbial biomass (-5 %). Moreover, compared to no defoliation plots, defoliation significantly decreased soil fungal diversity and altered fungal communities, particularly decreasing the relative abundance of Glomeraceae fungal taxa favorable to the formation of soil aggregates. Trampling only slightly attenuates the involvement of microorganisms (indirectly, −7 %) in aggregate formation by increasing soil compaction (directly, −4 %), and the positive effects from accelerating litter-derived C inputs due to trampling disturbance may counteract these limited negative effects. Our results highlight the negative effect of biomass removal by ungulates on soil aggregation, and suggest that the role of plant inputs and soil microbial properties on soil function and their correlation with soil aggregate stability needs to be explored under a diversity of grazing management strategies to refine management to improve soil conservation, C persistence and restore grasslands. • Defoliation rather than trampling dominantly decreased soil aggregate stability. • Negative effect of trampling on soil aggregate stability was overestimated. • Trampling slightly reduced MWD by increasing soil compactness and litter inputs. • Defoliation decreased MWD by reducing plant inputs and altering fungal community. [ABSTRACT FROM AUTHOR]

Although LLC converters are attractive in industrial applications due to its advantages of soft switching, high efficiency, and simple control, in wide voltage gain range applications, large switching frequency operating range is required, which may cause the loss of soft switching operation and existence of control instability issue. In this article, a novel LLC converter with two LLC resonant tanks is proposed. The proposed converter has three operation modes, namely, dual full-bridge operation mode, full-bridge operation mode, and half-bridge operation mode, which can cover the high voltage gain range, medium voltage gain range, and low voltage gain range operations, respectively. The operational principles of the proposed converter are presented, and brief design considerations are discussed. A 250 W experimental prototype with six times input voltage range (50–300 V) was built to validate the theoretical analysis of the proposed converter. Comparisons among different LLC topologies for wide voltage gain range applications are made. [ABSTRACT FROM AUTHOR]

Hold-up time operation is a crucial requirement for distributed power systems and server power supplies. LLC resonant converter is widely used in these applications due to its high efficiency and power density characteristics. Conventional pulse frequency modulation (PFM)-controlled inductor-inductor-capacitor (LLC) resonant converter requires a wide switching frequency operation range to satisfy the hold-up requirement. In this article, a novel control scheme is proposed for stacked structure LLC resonant converter. During the normal operation, the frequency doubler modulation strategy is adopted to reduce the switching loss and driving loss, and the output is regulated by PFM. During the hold-up time operation, the pulsewidth modulation is adopted to increase the system voltage gain, where the switching frequency is fixed during this operation stage. For the proposed converter, the resonant tank parameters are designed at the nominal operation point, and the only design consideration for the magnetizing inductor is the zero-voltage switching for primary switches. Therefore, compared with PFM-LLC, both the switching frequency operating range and the circulating current are reduced, and high efficiency feature is obtained. Finally, a 100-W experimental prototype with input voltage range of 160–340 V was built to validate the advantages of the proposed converter. [ABSTRACT FROM AUTHOR]

LLC resonant converters have been widely used in many different industrial applications. Analysis and design methodologies have great effect on the converter performance. Accordingly, a complete step-by-step optimal design methodology based on time-domain analysis has been proposed for an LLC resonant converter in this article. The proposed design methodology is implemented under the worst operation condition, and the following considerations are included to obtain the suitable design area: operation mode; voltage stress for resonant capacitor; zero voltage switching operation for primary switches; and resonant tank root-mean-square current. Then, by finding all possible design candidates and comparing them based on the power loss model, the optimized design candidate can be found. Compared with the existing design methodologies, the proposed one has the advantages of high accuracy and small computation requirement, which makes it application in industry possible. Finally, a 192-W experimental prototype was built to validate the effectiveness of the proposed design methodology. In addition, a MATLAB graphical user interference program was built based on the proposed design methodology to visualize and facilitate the design process for engineers. [ABSTRACT FROM AUTHOR]

The cascaded H-bridge (CHB) inverter is one of the most attractive multilevel topologies for renewable energy applications. Due to the fact that CHB inverters employ a large number of components, they suffer from a higher probability of fault, which reduces the system reliability. A fault-tolerant operation for a CHB inverter is described in this article. New features ensure reliable and robust operation of the converter in the event of a fault. The proposed strategy uses an additional cross-coupled CHB (X-CHB) unit in companion with the existing CHB units to support the output voltage and ensure continuity of operation in the event of an open/short-circuit fault. The operation of the proposed X-CHB inverter is described in detail. Simulation and experimental verification of the proposed concept are demonstrated using a seven-level CHB. Both simulation and experimental results confirm the fault-tolerant operation of the X-CHB for a battery energy storage system in case of switch faults. [ABSTRACT FROM AUTHOR]

In this article, based on the LLC resonant converter fundamental harmonic analysis model, the modulation strategies for LLC resonant converter can be categorized into the following three groups: 1) input voltage fundamental harmonic modulation; 2) resonant tank elements modulation; and 3) secondary equivalent impedance modulation. Operational principles and control diagrams for different modulation strategies are given. Comprehensive comparisons between these modulation strategies in terms of topology complexity, control complexity, and voltage gain range are presented with respect to the same system specifications. The advantages and disadvantages for each modulation strategy are summarized to provide guidance for engineers when analyzing and designing an LLC resonant converter. The hybrid modulation strategies are categorized into different groups based on the specific applications. Brief introductions of these hybrid modulation strategies are presented. Future trends regarding the modulation strategies of LLC resonant converters are presented. [ABSTRACT FROM AUTHOR]

In this letter, a magnetically controlled single-stage ac–dc converter is proposed for low-power application which has the following features. First, single-stage operation is achieved by sharing switches between LLC resonant converter and totem-pole bridgeless power factor corrector (PFC) converter. Second, the power factor correction function is inherently achieved by designing the PFC converter to operate in discontinuous conduction mode. Third, the dc-link voltage is almost constant. Fourth, fixed switching frequency and duty cycle can be implemented for the switches, which simplifies the magnetic component and driver circuit design. Fifth, the LLC resonant converter is designed to operate at series resonant frequency, the highest efficiency operating point, so the converter can always achieve the maximum efficiency operation. Meanwhile, at this operating point, the converter output voltage is independent of the load so that it is functioning as a dc transformer; and finally, soft switching for all semiconductors is achieved. A 75-W experimental prototype is built to validate the proposed magnetically controlled single-stage ac–dc converter [ABSTRACT FROM AUTHOR]

The LLC resonant converters commonly adopt frequency modulation (FM) or combination of FM with phase-shift modulation to regulate its output voltage. However, in these control schemes, a variable switching frequency range is required, which makes the magnetic components design complicated. Therefore, in this article, magnetic control (or variable inductor control) is adopted to make the converter operating at constant switching frequency and constant duty cycle. The fundamental harmonic analysis is commonly used because of its characteristic of simplicity. However, the accuracy of this method is reduced and considerable errors occur when the switching frequency or output power changes. Therefore, an optimal design methodology based on time-domain analysis of the LLC resonant converter with magnetic control is proposed in this article. The proposed methodology can assure that the converter will operate in PO or OPO modes within the whole operating range, and zero voltage switching operation for primary switches and zero current switching operation for secondary rectifier will be guaranteed. In addition, by limiting the resonant tank root-mean-square current, the system efficiency is improved. A 200-W experimental prototype is built and the effectiveness of the proposed optimal design methodology is verified. [ABSTRACT FROM AUTHOR]

In this paper, a dual half-bridge LLC resonant converter with magnetic control is proposed for the battery charger application. The primary switches are shared by two LLC resonant networks, and their outputs are connected in series. One of the LLC resonant converters is designed to operate at the series resonant frequency, which is also the highest efficiency operating point, and the constant output voltage characteristic is achieved at this operating point. The second LLC resonant converter adopts magnetic control to regulate the total output current and voltage during both constant current charge mode and constant voltage charge mode. Meanwhile, the function decoupling idea is adopted to further improve the system efficiency. The significant amount of the power is handled by the LLC resonant converter operating at the series resonant frequency, whereas the second LLC resonant converter fulfills the responsibility to achieve closed-loop control. By carefully designing the resonant networks, the zero-voltage switching for primary switches and zero-current switching for secondary diodes can be achieved for whole operation range. A 320-W experimental prototype is built to verify the theoretical analysis, and the maximum efficiency is measured about 95.5%. [ABSTRACT FROM AUTHOR]

Legume-grass mixtures are often used to increase forage yield and soil fertility in managed grasslands, but it remains unclear whether these benefits could be further improved by utilizing optimal legume-grass seeding ratios and phosphorus (P) fertilization. Here, we conducted a 5-year field experiment across 3 sites to investigate the effects of legume-grass seeding ratio and P fertilization on forage yield and soil quality. This experiment included mixtures comprised of two legume species and two grass species at five legume-grass ratios (3:7, 4:6, 5:5, 6:4, and 7:3), and monoculture of each species. P fertilizer was applied at the rate of 0, 9, 18, or 27 kg P ha-1 year-1. Plant diversity effects, e.g., complementarity and selection effects, were assessed by comparing yield of mixtures with monocultures. Our results show that a legume-grass mixture with a seeding ratio of 3:7 under moderate P fertilization resulted in the highest forage yield among all monocultures and mixtures, for each of the three sites, with persistent and consistent transgressive overyielding. Notably, greater soil organic matter, total nitrogen, enzymatic activity, and microbial biomass were observed with the legume-grass ratio of 3:7, compared to monocultures or other seeding ratios. Structural equation modeling indicated that the legume-grass ratio of 3:7 achieved highest yield through directly improving complementarity effect, and indirectly promoting selection effects because of increased fungal biomass. P fertilization directly enhanced soil nutrient and enzymatic activities, and further improved complementarity effect, resulting in high forage yield and soil quality. These results indicate that forage diversification practices with low legume-grass seeding ratios and moderate P fertilization can simultaneously benefit forage production and soil quality in managed grasslands. Overall, our study suggests that low legume seeding proportion in legume-grass mixtures combined with moderate nutrient management is a useful strategy for sustainable and highly productive managed grasslands. [ABSTRACT FROM AUTHOR]

• Grazing promoted soil organic carbon (SOC) formation from litter carbon. • The positive effect of grazing on SOC formation was due to defoliation and trampling. • Defoliation reduced plant cover and enhanced UV intensity arriving litter surface. • The increased UV intensity enhanced microbial assimilation of litter carbon. • Trampling also enhanced SOC formation directly by mixing litter and soil. Grasslands store 10–30 % of the global soil organic carbon (SOC) and have the potential to mitigate the increase in atmospheric CO 2 concentrations. Grazing plays a crucial role in regulating SOC storage in grassland ecosystems. However, the mechanistic understanding of how grazing influences the SOC dynamic still needs to be improved. We investigated how grazing-induced microenvironment changes influence the microbial assimilation of plant litter C and SOC formation from decomposed litter C in a multi-year field experiment, where grazing was simulated with mowing, dung and urine return, and trampling. We incubated 13C labeled litter in PVC collars to trace the microbial assimilation of litter C and the fate of litter C in the SOC after decomposition. While the grazing treatments changed soil properties marginally, mowing decreased above-ground plant biomass, litter mass, plant height, and plant cover (−12 % to −79 %). Accordingly, mowing treatment increased the exposure of litter to UV radiation (+38 %) and therefore facilitated the microbial assimilation of litter C (+20 %) and the SOC formation (+15 %). Trampling treatment promoted the transformation of litter C to SOC pools by mixing litter and soil (+34 %). Dung and urea return treatment did not affect SOC formation due to a marginal change in available nitrogen. Collectively, our results suggest that grazing facilitates litter-derived SOC formation by regulating microbial involvement through changes in the microenvironment. Our study indicates that grazing promotes SOC formation from plant litter, which maintains SOC storage in grasslands. Accurate quantification of the contribution of plant C input to SOC pools in different grasslands under various utilization is the next step to better predict SOC dynamics. [ABSTRACT FROM AUTHOR]

Defoliation, often induced by herbivores, and soil microbiomes are recognized as key drivers of plant diversity and productivity in grasslands. However, lack of experiments simultaneously manipulating defoliation and soil microbial diversity has constrained our understanding of how these two factors interactively influence both above‐ground and below‐ground net primary productivity (ANPP and BNPP).We employed a soil filtering approach to create the gradient of soil microbial diversity and removal of above‐ground biomass by clipping to simulate defoliation effect from herbivores. Our goal was to investigate how soil microbial diversity affected both ANPP and BNPP under the stress of defoliation.We found that defoliation and soil microbial diversity loss decreased the ANPP and BNPP of the plant community, and Medicago falcata (legume) was more responsive to these treatments than Leymus chinensis (grass) and Artemisia frigida (forb). ANPP was positively correlated with soil microbial richness only when plants suffered defoliation. By contrast, BNPP showed a closer relationship with soil fungal richness than bacteria, and defoliation enhanced this relationship. The structural equation model (SEM) showed that defoliation indirectly regulated ANPP by affecting plant P content, while soil bacterial diversity loss decreased the ANPP through altering plant P and fungal diversity loss directly decreased BNPP. The LEfSe and linear regression analysis revealed that the biomarkers of bacteria (e.g. Actinobacteria, Xanthobacteraceae) and fungi (e.g. Ascomycota, Glomerales) significantly contributed to the variation of ANPP and BNPP under defoliation treatment respectively. Defoliation enhanced phosphorus acquisition by soil microorganisms, further strengthening the microbial regulation of plant productivity.Overall, we provide novel insights on how defoliation enhances the positive effects of soil microbial diversity on above‐ and below‐ground net primary productivity. Our findings highlight that soil microorganisms associated with phosphorus cycling are mobilized to play a more active role in promoting productivity after defoliation. It may provide a new perspective on how to better utilize the role of soil microorganisms in grazed or managed grasslands. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

• Trampling increased losses in litter mass and carbon by promoting soil-litter mixing. • Trampling facilitated microbial assimilation and stabilization of litter carbon. • Trampling increased soil organic carbon formation but did not affect priming effects. • Trampling enhanced net soil organic carbon accumulation. Plant litter is an important source of soil organic carbon (SOC) in terrestrial ecosystem. The formation of SOC from plant litter and SOC mineralization to atmosphere is a critical determinant of long-term net ecosystem C balance. While it is generally understood that grazing plays a role in SOC cycling, what mechanisms are involved in driving SOC dynamic are not clear. Trampling enhances microbial processes by incorporating litter into the soil, likely influencing the fate of litter C and SOC mineralization. We conducted a controlled microcosm experiment to assess the role of trampling on the fate of litter C, litter-derived SOC mineralization (priming effect), and net C balance through incubation of 13C isotopically labelled Stipa krilovii litter placed on the soil surface, or incorporated into soil via simulated trampling, for 6 months. Litter C transferred into the SOC pool was further fractionated into mineral-associated soil organic carbon pool (MASOC, <53 μm) and particulate organic carbon pool (POC, >53 μm). We analyzed soil enzyme activities and litter-derived microbial biomass carbon (MBC) to determine microbial activities. We found trampling increased overall losses in litter mass (+16%) and litter C (+14%), with proportionally more decomposed litter C transferred to SOC pools (MASOC + 47% and POC + 157%), compared to absence of trampling. The litter-derived MBC was positively correlated with SOC formation, which was increased (+40.78%) by trampling, indicting a stronger microbial contribution to SOC formation. The disturbance of trampling did not induce significant positive priming effects, consistent with invariant soil total MBC and soil enzyme activities following trampling. As a result, trampling induced an increase in SOC formation and invariant priming effect, which contributed to positive net soil C balance (-230.74 ± 89.44 vs 100.33 ± 32.65 mg C/kg soil). Our results show trampling incorporates litter into soil and promotes microbial utilization of litter C and physiochemical stabilization of decomposed litter C, suggesting trampling is an important mechanism of SOC storage with litter C efficiently transferred into SOC pool. We demonstrate the importance of trampling in SOC formation and stabilization. Our findings indicate SOC formation efficiency from C input should be included in SOC predictive models in managed ecosystems. [ABSTRACT FROM AUTHOR]

Enhancing the micro-channel flow mixing is always a difficult problem. In this study, a micromixer based on induced charge electro-osmosis is proposed. A T-shaped micromixer, which has a chamber with conductive surfaces in the channel, is chosen. Due to the electro-osmotic effect of the induced charge, the induced potential is generated on the conductive surface. The Oldroyd-B constitutive model is chosen to characterize the flow characteristics of polyacrylamide solution, and an open-source solver named rheoTool based on the finite-volume method is used. The effect of the chamber shape, the chamber size, the conductive edge numbers in the chamber, and the applied electric intensity on the mixing efficiency are investigated. The results show that the micromixer with conductive edges in the chamber has better mixing effect because of the vortices. At the same time, compared with other shapes, the micromixer with diamond chamber has the best mixing effect, and the mixing efficiency reaches 79.51%. In addition, the mixing efficiency of one conductive edge in the diamond chamber is 4.39% higher than that of the two conductive edges chamber. It is found that increasing the chamber size will improve the mixing efficiency, and the mixing efficiency increased by 12.76% with the increase in chamber size. On the other hand, when increasing the electric field intensity from 100 to 200 V/cm, the mixing efficiency will decrease. [ABSTRACT FROM AUTHOR]

[Display omitted] • A series of MgO-x synthesized from Mg-MOF-74 was used to remove fluoride. • The adsorption capacities of MgO-500 and MgO-700 were 151.11 and 173.30 mg g−1. • MgO-x exhibit excellent anti-interference capabilities in the treatment of the polluted lake. • The adsorption mechanism mainly involves ligand exchange. Magnesium oxide (MgO), an inexpensive and non-toxic substance, is considered an excellent and environmentally friendly fluoride adsorbent. In this study, a series of MgO-x materials (MgO-300, MgO-500, MgO-700 and MgO-800) were obtained by calcination with Mg-MOF-74 as a precursor, and they were used for efficient fluoride removal from wastewater. Both MgO-500 and MgO-700 exhibit excellent fluoride adsorption capacity in the pH range of 3.00–10.00. Specifically, their maximum adsorption capacities are 151.11 mg g−1 and 173.30 mg g−1, respectively. By analyzing the adsorption isotherm and kinetic data, it is confirmed that the adsorption of F− by MgO-x is more in line with the Langmuir isotherm model and the pseudo-second-order kinetic model. Interestingly, the adsorption rate of MgO-500 was significantly faster than that of MgO-700. MgO-x exhibited excellent repeat application performance, with MgO-500 maintaining 75.5 % fluoride ion removal efficiency and 81.5 % regeneration efficiency after five adsorption/desorption cycles. FTIR and XPS analyses show that the adsorption mechanism of fluorine on MgO-x is mainly the result of ligand exchange and electrostatic attraction. Density functional theory calculations show that the adsorption of fluorine on the MgO (1 1 0) plane is more favorable than on the (1 0 0) plane. This study demonstrates that magnesium oxide derived from Mg-MOF-74, as an economical and environmentally friendly material, has great potential to remove excess fluoride from water. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel MoS 2 -TpTa composites were successfully synthesized and used for gold recycling from e-waste. • MoS 2 and COF components in the composite exhibited synergistic effects in gold adsorption. • MoS 2 -TpTa composite exhibited ultra-high gold adsorption capacity of 2564.80 mg g−1. • Composites demonstrate exceptional gold selectivity in the processing of real e-waste. • Gold adsorption mechanism is a contribution of coordination and redox reactions. The development of high-efficiency adsorbents for recovering gold from electronic waste has significant economic and environmental benefits. In this work, the efficient and selective adsorbents (MoS 2 -TpTa-0.5, MoS 2 -TpTa-1.0 and MoS 2 -TpTa-1.5) were fabricated by combining TpTa, a COF material obtained by condensing 2,4,6-Triformylphloroglucinol (Tp) and 4,4′'-Diamino-p-terphenyl (Ta), with MoS 2 for gold adsorption from electronic wastewater. The interaction between MoS 2 -TpTa and Au(III) occurred through an irreversible monolayer chemical adsorption mechanism, exhibiting adherence to both the pseudo-second order kinetics model and the Langmuir adsorption isotherm model. Remarkably, the MoS 2 -TpTa-1.5 composite exhibited an impressive maximum adsorption capacity of 2564.80 mg g−1 at an initial pH of 5.0. In addition, it exhibited selectivity for Au(III) recovery from a simulated solution that included coexisting ions of Pb(II), Cu(II), Co(II), Mn(II), Ni(II), Mg(II), Zn(II), and Li(I). Meanwhile, the MoS 2 -TpTa composite can completely adsorb Au(III) from the lixivium of discarded circuit boards from mobile phones in as little as 5 min. In addition, MoS 2 -TpTa demonstrated good repeatability over five adsorption cycles. SEM, XPS and XRD characterization were employed to study the adsorption mechanism, revealing the coordination between Au(III) and N, O, and S functional groups. Subsequently, the presence of S2- in the material resulted in the conversion of Au(III) ions to gold nanoparticles through reduction. The gold particles generated relatively large isolated clusters with a mean diameter reaching an astonishing 0.31 μm, exhibiting a regular hexagonal shape. This study proposes the combination of COF materials with metal sulfides to obtain composite materials with excellent adsorption performance, high selectivity and recyclability, holding substantial potential in practical electronic waste treatment for gold recovery. [ABSTRACT FROM AUTHOR]

Light-emitting diodes (LEDs) are widely used in street lighting, landscape lighting, liquid crystal display (LCD) backlighting, healthcare, etc. As an important part of LED lighting products, LED driver plays a vital role in maintenance costs reduction, energy saving and lifetime prolongation. In this paper, a single-stage LED driver is proposed, which is integrated by a totem-pole bridgeless power factor correction (PFC) unit and several modular LCL-T resonant rectifiers. The totem-pole bridgeless PFC unit and the LCL-T resonant rectifiers are integrated by sharing switches, which can simplify the circuit and reduce the system cost. The output current can be regulated by applying the variable inductor control. Constant duty cycle and fixed switching frequency operation can be achieved as well. The operating principle and the performance of the proposed converter are analyzed in this paper. In addition, a precise parameter design method is proposed by considering the high-order harmonics. At last, an experimental prototype is established to validate the proposed parameter design and variable inductor control method. [ABSTRACT FROM AUTHOR]

Gallium nitride (GaN) devices are widely used due to their excellent performance when integrated into power electronics applications. However, owing to their low parasitic parameters and fast switching speed, they are more prone to instability than the silicon devices. The sustained oscillation discussed in this article is one of the instability problems, which may result in overshoot or even more serious device breakdown; thus, it is pretty necessary to suppress it effectively in practical applications. It is the first time to adopt an RC snubber to suppress the sustained oscillation in this article, which is very simple and cheap but effective. First, the sustained oscillation modeling based on a double pulse circuit is carried out. Then, the RC region is established quantitatively according to the root locus analysis results, which makes up for the defects of these qualitative methods before. Furthermore, it is first found that the sustained oscillation can be fully suppressed due to the existence of dipoles. Finally, the oscillation suppression effect within the RC region is compared with that outside the region by the simulation and experimental results, which are consistent with the theoretical analysis. Additionally, the possible negative influence of the added RC snubber is also discussed in this article, which shows that it has a little impact on the switching speed and energy loss, while the sustained oscillation is well suppressed. [ABSTRACT FROM AUTHOR]

In order to realize power flow control among photovoltaic (PV) panel port, battery port, and load port in the distributed photovoltaic power generation system, integrated three-port dc–dc converters (TPCs) are widely adopted. The objective of this article is to provide a comprehensive, comparative, and insightful analysis and overview of these TPCs. First, based on the power transmission and control requirements of the system, five topological structures of three-port dc–dc conversion system (TPCS) composed of two or three two-port dc–dc converters are presented. And the five structures are comparatively analyzed. Second, based on these topological structures, and combing with the basic two-port dc–dc converters, three groups of typical TPCs with different galvanic isolation requirements are derived, respectively, by sharing switches, combining branches, etc., And comprehensive analysis, comparisons, and reviews of these TPCs with different structures of each isolation type are presented with tables and figures. Finally, the comparison results of the three isolation groups are summarized, which leads to a guidance for the selection of TPCs in different applications, and then some suggestions for the future research on TPCs are given. [ABSTRACT FROM AUTHOR]

With the growing adoption of wide bandgap devices in power electronic applications, current sensor design for switching current measurement has become more important. The demands for high accuracy, high bandwidth, low cost, compact size, and galvanic isolation pose significant design challenges. The conventional modeling approach for bandwidth analysis of current transformer sensors assumes that the magnetizing inductance remains constant, which does not always hold true in high-frequency operations. This can result in inaccurate bandwidth estimation and affect the overall performance of the current sensor. To address this limitation, this paper provides a comprehensive analysis of nonlinear modeling and bandwidth, considering the varying magnetizing inductance in a wide frequency range. A precise and straightforward arctangent-based fitting algorithm was proposed to accurately emulate the nonlinear feature, and the fitting results were compared with the magnetic core's datasheet to confirm its accuracy. This approach contributes to more accurate bandwidth prediction in field applications. In addition, the droop phenomenon of the current transformer and saturation effects are analyzed in detail. For high-voltage applications, different insulation methods are compared and an optimized insulation process is proposed. Finally, the design process is experimentally validated. The bandwidth of the proposed current transformer is around 100 MHz and the cost is around $20, making it a low-cost and high-bandwidth solution for switching current measurements in power electronic applications. [ABSTRACT FROM AUTHOR]

Due to the contradiction between [ABSTRACT FROM AUTHOR]

In order to further improve the efficiency of dual-active-bridge (DAB) converter, a hybrid five-variable modulation scheme with minimal root mean square (rms) current is proposed in this article, which combines the traditional phase-shift and pulsewidth modulation schemes. By adopting the proposed optimal scheme, a wider zero-voltage switching (ZVS) operation range and lower rms current level are achieved simultaneously when compared with other modulation schemes, which significantly improves the efficiency of the DAB converter. Moreover, for the complexity of the proposed modulation scheme with five variables, the Fourier decomposition based analytical expressions are derived for the converter and a generalized performance analysis results are presented. Besides, in order to avoid the analysis error, especially at light-load condition, the optimization strategy takes the rms current as the optimal objective, which includes the eight harmonic component of the inductor current rather than just considers the fundamental component. And an offline particle swarm optimization algorithm is introduced to acquire the optimal operating points for the whole power range. To substantiate the effectiveness of the proposed modulation scheme, a comprehensive comparison among related works in terms of the rms value and ZVS range were carried out under various operation condition. Finally, a 1.2 kW experimental platform was built and the highest experimental efficiency under the proposed modulation scheme reaches 96.8%. [ABSTRACT FROM AUTHOR]

The boost of convolutional neural networks (CNNs) has promoted the development of face recognition. Recently, the emergence of margin-based loss functions has further significantly improved the performance of face recognition. However, these methods sharply degrade in performance when dealing with large intra-class variations, including age, pose, illumination, resolution, and occlusion. Unlike most methods that target specific variations, our proposed approach, HAMFace, addresses the problems uniformly from the perspective of hard positive examples. To mitigate the intra-class variance, we argue that hard positive examples prefer larger margins, which can push them closer to their corresponding class centers. First, we design a hardness adaptive margin function to adjust the margin according to the hardness of the hard positive examples. Then, to enhance performance for unconstrained face recognition with various intra-class variations, we introduce a novel loss function named Hardness Adaptive Margin (HAM) Softmax Loss. This loss function allocates larger margins to hard positive examples during training based on their level of hardness. The proposed HAMFace is evaluated on nine challenging face recognition benchmarks and exhibits its superiority compared with other state-of-the-arts. • Hard positive example. • Hardness Adaptive margin loss. • SOTA results 9 benchmarks. [ABSTRACT FROM AUTHOR]

Asymmetric duty modulation (ADM), as a recently proposed modulation scheme, provides new chance to improve the performance of dual active bridge (DAB) converter. On this basis, an optimal ADM (OADM) scheme is proposed in this article to minimize the inductor peak-to-peak current over the whole voltage and power range. First, the DAB converter adopting ADM scheme is analyzed in frequency-domain and time-domain, and four operating modes are established. Then, the minimum peak-to-peak inductor current for each operating mode is obtained under Karush–Kuhn–Tucker condition, and the corresponding optimal closed-loop control with low calculation complexity is derived. Then, the key values and features of the OADM scheme are compared with recent state of the art, mainly including the inductor root mean square current and soft-switching performance. Finally, an experimental prototype was built to validate the efficiency enhancement of the converter by adopting the proposed OADM scheme. [ABSTRACT FROM AUTHOR]

In this article, an efficiency-oriented hybrid duty modulation (HDM) scheme is proposed for the dual active bridge (DAB) converter that can reduce the inductor root-mean-square (rms) current and extend the switch soft-switching range. First, a complete description of the combination forms of different modulation schemes is presented considering the allocation of the zero-voltage portion. A unified description for these combination forms is obtained in the frequency domain. Second, the symmetric–symmetric duty modulation (SSDM) scheme and asymmetric–symmetric duty modulation (A2SDM) scheme are established to minimize the inductor rms current by considering its fundamental component. Third, the characteristics of SSDM, A2SDM, and the traditional phase shift modulation schemes are compared from several aspects, mainly including the inductor rms current and the soft-switching performance. Furthermore, the loss breakdown analysis results for the three modulation schemes are presented and compared. According to these results, the HDM scheme is proposed to improve the overall efficiency of the DAB converter. Finally, an experimental prototype was built with a peak efficiency of 97%, which validates the effectiveness of the proposed modulation scheme. [ABSTRACT FROM AUTHOR]

High step-up boost converters with coupled inductor have attracted much attention in the fuel cell or photovoltaic grid-connected generation system, however, there are few literatures elaborated on the construction ideas and derivation methods of them. Accordingly, in order to obtain a clear roadmap on the derivation and inner connection of these converters, a comprehensive review and analysis are presented in this paper. First, the basic boost converter with coupled inductor is regarded as the basic topology, and its merits and demerits are analyzed in detail. Then, in order to address these demerits, various step-up techniques are introduced, such as the rectifier circuit, the active-clamped circuit, the multi-winding coupled inductor, and the voltage doubler rectifier; and numerous new topologies are continuously proposed by combinations and equivalent simplifications. In addition to a detailed synthesis of each topology, a comparative and quantitative analysis among some important converters is presented, and the optimal one is chosen to build a 250 W prototype. Finally, based on comparisons and analysis, the main characteristics and inner connections of these high step-up boost converters with coupled inductor are identified and clarified. [ABSTRACT FROM AUTHOR]

Many studies have concentrated on fixed cost and resource allocation issues by using data envelopment analysis (DEA). The existing approaches allocate fixed cost or resource primary based on efficiency principle. They usually assume that all of the DMUs become efficient after fixed cost or resource allocation. However, due to the existing of technology heterogeneity among DMUs, it is impractical for all the DMUs to achieve a common technology level, especially when some DMUs are far from the efficient frontier. In this paper, under the centralized decision environment, we present a new approach to deal with fixed cost and resource allocation problems by considering the factor of technology heterogeneity. Specifically, the concepts of meta-efficiency and group efficiency as well as meta-technology ratio are firstly introduced to reflect the technology level of the DMUs. Then two centralized DEA models considering technology heterogeneity are proposed to allocate fixed cost and resources, respectively. Finally, two numerical examples are presented to illustrate the feasibility and superiority of the proposed approach compared with prior studies. [ABSTRACT FROM AUTHOR]

The temperature sensitivity (Q 10 values) of soil respiration (Rs) has been a source of much debate given the potential feedbacks between soil carbon pools and global warming. Many studies have been conducted to investigate monthly variations in Q 10 values. However, few studies have focused on the underlying causes of the variations, and it no clear how seasonal variation in soil physicochemical properties could affect Q 10 . The fairy rings (FRs) caused by basidiomycete fungi can change soil physiochemical properties. Therefore, we collected a series of soils over five months (June–October) from three zones impacted by FRs: outside (OUT), on (ON) and inside (IN) the rings to explore the relationship between soil physicochemical properties and Q 10 values. We observed significantly higher plant biomass, plant nitrogen content and soil available phosphorus (P) in the ON zone than the OUT and IN zones ( p  < 0.05). Soil total carbon, nitrogen and water content decreased significantly from the OUT zone to the IN zone. In contrast, soil pH increased significantly from the OUT zone to the IN zone. The Q 10 values increased significantly as months passed, different zones followed the order IN > OUT > ON ( p  < 0.05), and the response of Rs to the zones and progression through the months was the opposite to that of Q 10 values. Our study suggest that soil available P and water content were two dominant factors influencing temporal patterns in Q 10 , and that soil pH was closely related to Rs, which can also affect Q 10 indirectly. [ABSTRACT FROM AUTHOR]

• Viscoelastic fluids have a higher mixing efficiency than Newton fluids. • The induced charge electroosmosis flow of viscoelastic fluids is unstable and time dependent. • The viscoelastic instability is amplified with the increase of polymer concentration and electric field intensity. Effective mixing at the microscale is crucial in bioengineering and chemical engineering. In this study, the mixing of viscoelastic fluids described by the Oldroyd-B constitutive model in the micromixer with a conductive cylinder was numerically studied. Based on the finite volume method, the EDL effect is approximated by the slip velocity on the surface using Helmholtz-Smoluchowski theory. The effects of the polymer concentration and applied electric field intensity on the mixing of polyacrylamide (PAA) solutions were investigated. The results show that the velocity decreases and the mixing efficiency increases with the increase of the polymer concentration. The mixing efficiency of the PAA solutions is 20-40% higher than that of the Newtonian fluid. When the electric field strength is increased from 100 V/cm to 200 V/cm, the mixing efficiency first decreases and then increases significantly for the PAA solutions from 100 ppm to 400 ppm, but the mixing efficiency for the 500 ppm PAA solution keeps increasing slowly. When the electric field intensity is 200 V/cm, the mixing efficiency of 500 ppm PAA solution reaches more than 99%. [Display omitted] [ABSTRACT FROM AUTHOR]

Soil biota could have a significant impact on plant productivity and diversity through benefiting plants and mediating plant-plant interaction. However, it is poorly understood how soil biotic factors interaction with abiotic environments affect plant community diversity and composition. Here, we investigate the community-level consequences of arbuscular mycorrhizal fungi (AMF) interactions with multiple nutrients and their ecological stoichiometry. We conducted a greenhouse experiment manipulating nitrogen (N) and phosphorus (P) to create soil nutrient availability and N:P gradients for microcosm communities with and without AMF. We found that AMF suppressed plant diversity at low P levels, whereas it did not alter the diversity at high P levels because of trade-offs in the abundance of the dominant and subordinate species. AMF reduced plant diversity at the intermediate N:P ratios, while AMF did not affect the diversity at low and high N:P ratios. P addition decreased the mycorrhizal contribution to community productivity, whereas N addition reduced the negative effects of AMF on productivity at high P levels. AMF decreased community productivity at low N:P ratios but increased it at high N:P ratios. AMF increased the stoichiometric homoeostasis of plant communities, which was positively correlated with the stability of productivity under variations in soil N:P ratios. Our study demonstrates that both resource availability and stoichiometry influence the effect of AMF on plant community productivity and diversity and suggests that AMF may increase the stability of plant communities under variations in the soil nutrients by increasing the stoichiometric homoeostasis of the plant community. [ABSTRACT FROM AUTHOR]

• A large sample of papers are reviewed by a citation network analysis. • Subjective analysis of 43 papers is employed to replenish the citation analysis. • Case studies primary focus on macro systems by modeling approaches. • The development trajectory and future research directions are identified. The water-energy nexus has gained great attention to both academe and practitioners in the past decade. In order to help expand the understanding in this field, we conduct a comprehensive literature review on water-energy nexus by using citation-based approach. A directional network is established in terms of citation relationships among 1185 related papers published in journals indexed by the Web of Science database from 2007 to 2019. Specifically, we first draw the citation chronological graph and main path analysis to show a complete picture of literature development trajectory since 2007. It is found that the current key route focuses on the understanding of coupling relations in macroscopic national systems, while the study of microscopic systems such as enterprises, families and individuals is lacked. In addition, considering that the citation-based approach may ignore the newest papers, 43 latest highly relevant papers are further analyzed in terms of study background, data source and modeling methods. To be specific, the main advantages and major limitations of existing approaches are identified. Finally, future research challenges and prospects are identified, including the shifts of research object: from macro systems to micro systems, the challenge of modeling: from analysis to analytics of big data, and the deepening of decision support: from knowing to doing. [ABSTRACT FROM AUTHOR]

Water and energy resource are inextricably linked. Rapid industrialization has led to severe water and energy shortage as well as environmental issues in China. In industrial sector, industrial production and wastewater treatment are two interdependent subsystems. Accordingly, understanding the internal operation performance of the two subsystems as well as assessing their coordination level are of great importance for sustainable water and energy usage. From the perspective of production efficiency, this paper aims to explore industrial water-energy nexus in China by proposing an interactive meta-frontier network DEA approach. The proposed approach is applied to assess the industrial water and energy utilization efficiency in the processes of industrial production and wastewater treatment from 2011 to 2015 in China. The results show that although eastern and central regions have high industrial production efficiency, most regions have relatively low wastewater treatment efficiency. In addition, the nexus degree of eastern region maintains a relatively high level and shows a stable improvement, while the rest two regions perform relatively worse. Comparing the central and western region, the industrial production technology of central region is better yet the wastewater treatment efficiencies of western region are higher, which results in higher nexus degree of western region. Based on the empirical results, policy implications are given in terms of national level, regional level and provincial level, respectively. [ABSTRACT FROM AUTHOR]

Simple Summary: Forages are an essential portion of ruminant rations to maintain rumen function. Exploring how orchardgrass and alfalfa interact in the rumen is necessary to better understand their feed use potential as both hay and silage. This study evaluated in vitro rumen degradation, fermentation characteristics, and methane production responses to different forage ratios of alfalfa and orchardgrass. The results indicate that dry matter and organic matter degradability and methane production were greater for mixed silages compared to mixed hays. A forage ratio of 50:50 for orchardgrass and alfalfa favor the growth of rumen microorganisms without compromising nutrient digestion and rumen fermentation. This study aimed to investigate the effects of different forage ratios of orchardgrass (Dactylis glomerata) and alfalfa (Medicago sativa) on in vitro rumen degradation and fermentation characteristics. Orchardgrass and alfalfa were harvested separately and prepared as hay and silage mixtures at ratios of 100:0, 75:25, 50:50, 25:75, and 0:100 (w/w on a dry matter basis) and anaerobically incubated for 48 h with rumen fluid obtained from lactating dairy cows. Fermented residues and cultured fluids were used to determine nutrient degradability, fermentation parameters, and associative effect indices. Increasing the proportion of alfalfa in hay and silage mixtures quadratically increased in vitro organic matter disappearance (IVOMD, up +5.14%) and marginally decreased in vitro neutral detergent fiber disappearance (NDFD, down −1.79%). Meanwhile, increasing the proportion of alfalfa accelerated the rumen fermentation process (e.g., gas production) and remarkably enhanced the growth of rumen microbes as indicated by microbial protein production (MCP, 13.4% increase). Increments of rumen degradability and methane production were more pronounced in silage mixtures than hay mixtures. In combination, a forage ratio of 50:50 for orchardgrass and alfalfa is recommended for both hay and silage in order to improve the feed use potential in ruminants. [ABSTRACT FROM AUTHOR]

• The total forage yield of perennial legume and grass intercropping system were higher than monoculture. • Interspecific interactions and P application contributed to transgressive overyielding. • The legume: Grass seeding ratio 3:7 under 80 kg ha−1 P fertilization had the highest intercropping advantage. • Alfalfa and orchardgrass were more competitive than sainfoin and tall fescue in this fully mixed intercropping system. • Adequate P application facilitated the forage yield and competitive ability but excessive P fertilizer suppressed. Although intercropping is a common technique that has been widely applied, the effect of phosphorus (P) fertilization on productivity of a fully-mixed perennial intercropping system composed of four species, including two legumes and two grasses, has rarely been studied. The objective of this study was to determine the effect of interspecific interactions on forage yield and the influence of P application on interspecific competitiveness and yield in a fully-mixed intercropping system of alfalfa (Medicago sativa L.), sainfoin (Onobrychis viciifolia Scop.), orchardgrass (Dactylis glomerata L.) and tall fescue (Festuca arundinacea Schreb.). A three-year (2016–2018) field experiment was conducted in central China with an annual rainfall and temperature of 456 mm and 9.5 ℃, respectively. Five legume and grass seeding ratios (L: G) of 5:5, 4:6, 3:7, 6:4, and 7:3 were included, with four monocultures used as the control. The total forage yield was measured when 20% of the alfalfa flowers had opened (BBCH 62). Competitiveness indices, including the land equivalent ratio (LER), aggressivity (A), relative crowding coefficient (K values), competitive ratio (CR), and actual yield loss (AYL), were assessed. The total forage yield increased under fully-mixed intercropping in 2017–2018 when a transgressive overyielding advantage was attained, which was contributed by the interspecific interactions and P application. Moreover, the maximum yield and highest intercropping advantage appeared in L: G 3:7 and L: G 5:5 under 80 kg ha−1 P application in 2017–2018. Additionally, adequate P (80 kg ha−1) contributed to higher A values, K values, CR, and AYL of alfalfa and orchardgrass than in sainfoin and tall fescue, which suggested greater interspecific benefits and land-use efficiency. The fully-mixed intercropping system of alfalfa, sainfoin, orchardgrass, and tall fescue realized these potential advantages by coordinating interspecific interactions and environmental resources, which were manipulated by P application. [ABSTRACT FROM AUTHOR]