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Mechanical behavior of press-induced deformation of polycarbonate at intermediate strain rates was studied by finite element method. Based on DSGZ constitutive model, polycarbonate cylindrical uniaxial compression finite element simulation was carried out. Effectiveness of the model for prediction of compressive mechanical response was verified by contrast of simulated and experimental results, calculation of prediction accuracy of model, and analyzation of multi-physics distribution in material after compressive deformation. Mechanical evolution rule of polycarbonate plates was obtained by simulation of the solid-state deformation in lateral restricted mode. The results show that simulated stress-strain curves is in good agreement with that acquired from experiment in the process of uniaxial compressive deformation, and stress-strain relationship in compressive elastic-plastic deformation can accurately predicted by DSGZ model relatively. The overall deformation of material was uniform, and the sensitivity of stress response to temperature is higher than that of strain rate in cylindrical uniaxial compressive deformation and press-induced deformed simulation. Mechanical behavior of press-induced deformation of polycarbonate was reflected by simulated results, which can be an important basis for engineering realization of press-induced deformation of polycarbonate, and provide strong support for material strengthening and its application in aircraft cockpit transparencies.

【Objective】 Amending soil with biogas slurry is a way to treat livestock wastes. This paper is to elucidate the combined effect of biogas slurry application and chemical fertilization on improving rice yield and soil quality. 【Method】 A two-year field experiment was conducted from 2021—2022, with the traditional chemical fertilization served as the control (CK). There were two biogas slurry treatments: 150 m3/hm2 and 300 m3/hm2, each associated with three chemical fertilizations by applying 25%, 50% and 75% of the chemical fertilizer traditionally used by local farmers. The fertilizers were applied in two or three top-addressings. In each treatment, we measured rice growth and changes in soil properties. 【Result】 ① In 2021, applying 300 m3/hm2 of biogas slurry combined with 25% of traditionally used fertilizer (topdressing 3 times) gave the highest yield at 9.88 t/hm2. In 2022, the highest yield was 10.4 t/hm2, achieved by applying 150 m3/hm2 of biogas slurry combined with 50% of traditionally used fertilizer (topdressing 3 times). In both years, applying 150 m3/hm2 of biogas slurry combined with 25% of traditionally used fertilizer but by topdressing twice only gave the lowest yield. Applying 300 m3/hm2 of biogas combined with 50% and 75% of traditionally used reduced the rice yield and taste of the grains. ② Increasing topdressing from 2 to 3 times increased rice yield when the fertilization was the same. ③ Applying biogas slurry increased soil organic matter by 7.1% to 52.4%. Increasing biogas slurry and chemical fertilization also increased alkali hydrolyzable nitrogen, available phosphorus, available potassium, phosphatase activity, and electrical conductivity (EC) of the soil, but had little effect on soil pH. Applying 150 m3/hm2 of biogas slurry combined with 25% of traditionally used fertilizer reduced alkali-hydrolyzable nitrogen, available phosphorus, and available potassium contents, compared to CK. Applying 300 m3/hm2 of biogas slurry combined with 50% of traditionally used fertilizer increased EC, alkali-hydrolyzable nitrogen, available phosphorus, and available potassium contents in the soil, compared to CK. ④ Applying 75% of traditionally used fertilizer increased soil phosphatase activities by 10.6% and 42.4%, depending on biogas slurry application, compared to CK. 【Conclusion】 Combing biogas slurry application and chemical fertilization can improve rice yield, soil nutrient contents, and enzyme activity only when applied at right rates. From our two-year experiment, applying 150 m3/hm2 of biogas slurry combined with 50%~75% of traditionally used fertilizers by topdressings the fertilizers 3 times is optimal for improving crop yield and soil quality.

The influences of ambient temperature on mechanical properties of polycarbonate（PC）were investigated. The results show that both tensile properties and flexural properties of PC decrease linearly with the increase of ambient temperature, and the linear correlation is good. When the ambient temperature rises from –40℃ to 130 ℃, the tensile yield stress of PC decreases by nearly 55% and the yield strain decreases by about 63%. When the ambient temperature rises from –70℃ to 130℃, the flexural strength of PC decreases by about 66% and the flexural modulus decreases by about 37%. In addition, the fracture morphology indicates that all tensile fractures at different temperatures originate from the surface of PC, and there are obvious mirror areas, fog areas and rough areas on the fracture surface. The fracture mode of PC changes from rapid brittle fracture at low temperature to ductile fracture at high temperature. However, the impact strength of PC increases first, then decreases and then increases with the increase of ambient temperature. The impact fracture mechanism of PC has a large degree of temperature difference. In the whole range of –40-145 ℃, the impact fracture morphology of PC shows a series of changes from fog zone to sawtooth zone, then to mirror zone, and finally softening and melting.

Piezo-photocatalysis is an emerging means to efficiently relieve energy crises and environmental problems. In this work, (Na, Sm) co-doped CaBi2Nb2O9 nanoplates with an average thickness of ∼100 nm are prepared by a molten salt method. The ultra-high piezo-photocatalytic performance is achieved by modulating the calcination temperature with a first-order kinetic constant (k) of impressive 0.7734 min−1 for 10 mg L−1 RhB, superior to most similar reported studies. The catalytic universality for other colored pollutants (methylene blue, methyl orange, and indigo carmine), antibiotics (tetracycline, tetracycline hydrochloride, and oxytetracycline), and an optimum hydrogen production of 183.60 μmol g−1 h−1 is demonstrated. The outstanding catalytic performance derives from the unique (Bi2O2)2+ layers, the dominant surface effect, and piezoelectric assistance. The synergistic effect of piezocatalysis and photocatalysis is described using the energy band bending mechanism and the separation behaviors of carriers. This work provides a feasible strategy for the preparation of powerful piezo-photocatalysts. [ABSTRACT FROM AUTHOR]

Plasmonic metal nanoclusters are widely used in chemistry, nanotechnology, and biomedicine. In metal nanocluster dimers, coupling of the plasmons leads to the emergence of two distinct types of modes: (1) bonding dipole plasmons (BDP), which occurs when charge oscillates synchronously within each nanocluster, and (2) charge transfer plasmons (CTP), which occurs when charge oscillates between two conductively linked nanoclusters. Although TDDFT-based modeling has uncovered some trends in these modes, it is computationally expensive for large dimers, and quantitative analysis is challenging. Here, we demonstrate that the semiempirical quantum mechanical method INDO/CIS enables us to quantify the CTP character of each excited state efficiently. In end-to-end Ag nanowire dimers, the longitudinal states have CTP character that decreases with increasing gap distance and nanowire length. In side-by-side dimers, the transverse states have CTP character and generally larger than in the end-to-end dimers, particularly for the longer nanowires. In side-by-side dimers where one nanowire is shifted along the length of the other, the CTP character of the longitudinal states peaks when the dimer is shifted by two Ag–Ag bond lengths, while the transverse states show decreasing CTP character as displacement increases. In the larger Ag31+ nanorod dimers, CTP character follow a similar distance dependence to that seen in the small nanowire but have smaller overall CTP character than the nanowires. Our study demonstrates that INDO/CIS is capable of modeling metal nanocluster dimers at a low computational cost, making it possible to study larger dimers that are difficult to analyze using TDDFT. [ABSTRACT FROM AUTHOR]