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Abstract A bio-based flame retardant nickel phytate (PA-Ni) was synthesized and combined with soybean oil-based polyol (SO) to create a green rigid polyurethane foam (RPUF) with enhanced compressive strength, good thermal stability and flame retardant. The results showed that the RPUF-SO2/Ni3 with 3 wt% PA-Ni had the highest initial and termination temperature, maximum thermal decomposition rate temperature and carbon residue, and better thermal stability. Its limiting oxygen index was increased by 2.6% compared with RPUF-SO2 without PA-Ni added, and the peak heat release rate (PHRR) and total heat release rate (THR) were reduced by 14.92% and 19.92%, respectively. In addition, RPUF-SO2/Ni3 had the lowest Ds under the conditions of flame (18.90) and flameless (22.41), and had the best smoke suppression effect. And the compressive strength of RPUF-SO/Ni3 was significantly enhanced by the addition of PA-Ni. The results show that the improvement of flame retardancy of RPUF is mainly the result of the combined effect of gas-phase and condensed-phase flame retardancy, among which the flame retardancy of RPUF-SO/Ni3 was the best. The current findings offer a practical way to produce green and low-carbon RPUF as well as promising prospects for the material's safe application.

In this work, a cost-effective organic package substrate embedded coupled magnetic core inductor technology is proposed and demonstrated for power supply in package applications. Based on a novel lithographic via process, it involves a solid copper pillar electroplating step for creating a groove and integration of the vertical interconnects of the inductor. The primary and secondary windings of the coupled inductor are interleaved on the rectangular magnetic composite core which is accommodated within the groove. The coupled inductor combines solid vertical interconnecting with low loss magnetic composite core, therefore bringing together tight process tolerances and superior current capability. Experimental results show that the 2.9-mm2 coupled inductor achieves a high inductance to resistance ratio of 0.28 nH/mΩ, and a coupling factor of 0.57. In addition, the proposed inductor achieves an ultra-high saturation current of 16.52 A that is the highest reported value for a high-frequency integrated magnetic core inductor to the best of our knowledge. The performance of the coupled inductor has been calculated for a standard 1.8 to 1 V interleaved converter. Notably, it demonstrated a remarkable efficiency exceeding 95% across a wide range of phase currents between 0.11 and 2.32 A.

Ammonium polyphosphate (APP) and self-made nickel phytate (PANi) were used as modified materials to prepare green biomass rigid polyurethane foam (RPUF). The flame retardancy, thermal stability, smoke toxicity and mechanical properties of the modified RPUF were investigated by limiting oxygen index (LOI), a cone calorimetry (CONE) test, thermogravimetric analysis and a compression test. The results showed that the RPUF with 10 wt% APP (PANi/APP10) had the highest LOI of 26.5%. Its peak heat release rate (PHRR) and total heat release (THR) were reduced by 29.64% and 24.05% compared with PANi/APP0 without APP. And its smoke production rate (SPR) and total smoke release (TSR) decreased by 33.14% and 19.88%, respectively. Compared with pure RPUF, the compressive strength of PANi/APP10 was increased by 50%, mainly because APP itself was an ultra-fine powder, which was better compatible with the matrix and improved the hardness of the material. The results showed that the synergistic effect of the gas phase and the condensed phase mechanism could effectively improve the flame-retardant effect. The current research results provided a new strategy for the preparation of green and low-toxicity RPUF.

This paper proposes a proximal policy optimization (PPO) algorithm for coupling matrix synthesis of microwave filters. With the improvement of filter design requirement, the limitations of traditional methods such as limited applicability are becoming more and more obvious. In order to improve the filter synthesis efficiency, this paper constructs a reinforcement learning algorithm based on Actor-Critic network architecture, and designs a unique filter coupling matrix synthesis reward function and action function, which can solve combinatorial optimization problems stably. [ABSTRACT FROM AUTHOR]

Cheap and widely available calcium-based materials have gained popularity for remediating cadmium-contaminated soils, but their potential to address cadmium (Cd) toxicity in acidic soils remains deeply understudied. The current study investigated the effects of calcined oyster shells (COS) and dolomite (DM), applied at a rate of 30 g kg-1, on Cd availability and its accumulation in spinach plants in acidic Cd-contaminated soils (Cd concentration: 4.42 mg kg-1). Additionally, the influence of active aluminium (Al) on Cd bioavailability and plant Cd accumulation was examined. The application of COS and DM led to a reduction in diethylenetriaminepentaacetic acid extracted Cd (DTPA-Cd) of 42.1% and 28.6%, respectively. Furthermore, the COS and DM positively increased soil pH (2.48 and 1.81 units), electrical conductivity (89.4% and 28.1%), organic matter content (17.2% and 11.9%) and available phosphorus (37.7% and 6.39%) and decreased soil exchangeable Al3+ (100% and 83.9%). As a result of amending with COS and DM, the Cd concentration (81.0%-82.9%) and bioaccumulation factor (78.8%-80.2%) in spinach plants were significantly decreased (p < .05). The presence of exchangeable Al3+ in the soil showed only a weak influence on plant Cd accumulation. The COS and DM also induced 8.65 times and 5.42 times greater spinach fresh matter yield compared with the control. In conclusion, the application of COS and DM as amendments in Cd-polluted acidic soils holds great promise. The COS has greater prospects for immobilizing Cd, promoting plant biomass and producing plants with lesser Cd concentrations in acidic soils. This work offers a new strategy by adopting wide-resource and cost-effective mineral materials for sustainable environmental management. [ABSTRACT FROM AUTHOR]

The utilization of the thin film gradient diffusion technique has been on the rise for appraising the efficacy of soil cadmium (Cd). Nonetheless, in contrast to conventional methodologies employed to gauge the efficacy of soil Cd, there exists a dearth of adequate research concerning whether the technique of diffusive gradients in thin films (DGT) can furnish a more precise and all-encompassing evaluation of soil Cd effectiveness in soil passivation and remediation procedures. Herein, this study selects four popular amendments (i.e. oyster shells, red mud, hydroxyapatite and biochar) and analyses the correlations among soil Cd availability, Cd uptake amount and spinach biomass. Results showed that the following concentration ranges: DGT-Cd (1.78-21.1 µg L-1), HAc-Cd (1.84-2.22 mg kg-1), DTPA-Cd (0.62-1.22 mg kg-1) and CaCl2-Cd (0.0489-0.103 mg kg-1). Among the methods, CaCl2 extraction had a lower capacity to extract soil Cd compared with the other methods. These amendments improved soil environment, promoted spinach growth and decreased plant Cd concentrations. Oyster shells and red mud treatments significantly reduced DGT-Cd levels (by 90.4% and 82.2%, respectively), which led to a reduction in plant Cd concentrations (by 77.1% and 72.4%) and bioconcentration factor (by 75.8% and 68.8%). Furthermore, oyster shells were found to be most effective in reducing soil-available Cd and inhibiting Cd uptake by spinach. Based on correlation analysis, the DGT method showed the largest measurement range and provided the best prediction of Cd accumulation in spinach compared with chemical extraction methods (R2 = .88, p <.001). Overall, the use of DGT in combination with plant uptake and chemical extraction data can provide a comprehensive assessment of soil Cd bioavailability. These findings facilitate an accurate and comprehensive evaluation of the bioavailability of Cd after applying amendments. These results also showed that oyster shells can be regarded as a promising eco-friendly and low-cost amendment for large-scale immobilizing Cd and producing plants with lesser Cd concentrations. [ABSTRACT FROM AUTHOR]

In order to explore the effect of heat shock treatment (HT) on the storage quality of fresh-cut lily bulbs, changes in the quality characteristics of lily bulb slices (Lilium davidii var. unicolor Cotton) exposed to heat shock treatment (hot water at 55 ℃, 2 min) were examined during storage at 4 ℃. The results demonstrated that HT effectively maintained the color of fresh-cut lily bulbs during storage and preserved the cell wall structure. The activities of peroxidase (POD), polyphenol oxidase (PPO), phenylalanine ammonia lyase (PAL) were suppressed by HT. Meanwhile, the accumulation of total phenolics (TP) and malondialdehyde (MDA) and the increase of relative electric conductivity (REC) were delayed, which led to reduced mass loss, decay rate, and browning degree. Comparison with the control group, the activities of POD, PPO and PAL in the HT group decreased by 95.26%, 21.74% and 41.65%, respectively. The decay rate, browning degree, MDA content, REC and TP content in the HT group were 10.56%, 1.55, 0.13 μmol/g, 19.71% and 3.51 mg/g, respectively, which were all significantly lower than those in the control group (P 0.05). Furthermore, plasma membrane dissolution did not appear in the HT group until the 40th day, which was 30 days later than the control group. Therefore, HT effectively delayed the quality deterioration of fresh-cut lily bulbs during storage and prolonged the storage time.