The electrical and thermal transport properties of metals become complicated in the intermediate and low temperature range ($0.1{\mathrm{\Theta }}_D-{\mathrm{\Theta }}_D$, with ${\mathrm{\Theta }}_D$ being the Debye temperature) due to electron-phonon inelastic scattering. For the Wiedemann-Franz law, a notable feature is that the Lorenz ratio significantly deviates from the Sommerfeld value. Although qualitatively theoretical understanding has been developed for decades, a mode-level first-principles analysis is still lacking in this temperature range and a better understanding of inelastic scattering and thermal transport mechanisms is desirable. In this work, we take aluminum and copper as examples. We find that two factors are essential to correctly predict the thermal conductivity and Lorenz ratio in the intermediate temperature range. First, the momentum relaxation time should be used for electrical conductivity calculations, while the energy relaxation time should be used for electronic thermal conductivity calculations. Second, proper choice of broadening parameter and fine sampling in the Brillouin zone is vital. Using the mode-level description of inelastic electron-phonon scattering at intermediate temperatures, the correct Lorenz ratio can be obtained within the present scheme, while using only the energy or momentum relaxation time cannot capture the correct trend of Lorenz ratio. The calculation scheme can be expanded to other metallic systems and is valuable for a better understanding of the transport properties of metals.

Using a density functional theory‐based thermal transport model, which includes the effects of temperature (T)‐dependent potential energy surface, lattice thermal expansion, force constant renormalization, and higher‐order quartic phonon scattering processes, it is found that the recently synthesized nitride perovskite LaWN₃ displays strong anharmonic lattice dynamics manifested into a low lattice thermal conductivity (κ_L) and a non‐standard κ_L∝T^−0.491 dependence. At high T, the departure from the standard κ_L∝T⁻¹ law originates in the dual particle‐wave behavior of the heat carrying phonons, which includes vibrations tied to the N atoms. While the room temperature κ_L=2.98 W mK^‐1 arises mainly from the conventional particle‐like propagation of phonons, there is also a significant atypical wave‐like phonon tunneling effect, leading to a 20% glass‐like heat transport contribution. The phonon broadening effect lowers the particle‐like contribution but increases the glass‐like one. Upon T increase, the glass‐like contribution increases and dominates above T = 850 K. Overall, the low κ_L with a weak T‐dependence points to a new utility for LaWN₃ in energy technology applications, and motivates synthesis and exploration of nitride perovskites.

Background: Controlling excess biomass accumulation and clogging is important for maintaining the performance of gas biofilters and reducing energy consumption. Interruption of bacterial communication (quorum quenching) can modulate gene expression and alter biofilm properties. However, whether the problem of excess biomass accumulation in gas biofilters can be addressed by interrupting bacterial communication remains unknown. Results: In this study, parallel laboratory-scale gas biofilters were operated with Rhodococcus sp. BH4 (QQBF) and without Rhodococcus sp. BH4 (BF) to explore the effects of quorum quenching (QQ) bacteria on biomass accumulation and clogging. QQBF showed lower biomass accumulation (109 kg/m³) and superior operational stability (85–96%) than BF (170 kg/m³; 63–92%) at the end of the operation. Compared to BF, the QQBF biofilm had lower adhesion strength and decreased extracellular polymeric substance production, leading to easier detachment of biomass from filler surface into the leachate. Meanwhile, the relative abundance of quorum sensing (QS)-related species was found to decrease from 67 (BF) to 56% (QQBF). The QS function genes were also found a lower relative abundance in QQBF, compared with BF. Moreover, although both biofilters presented aromatic compounds removal performance, the keystone species in QQBF played an important role in maintaining biofilm stability, while the keystone species in BF exhibited great potential for biofilm formation. Finally, the possible influencing mechanism of Rhodococcus sp. BH4 on biofilm adhesion was demonstrated. Overall, the results of this study achieved excess biomass control while maintaining stable biofiltration performance (without interrupting operation) and greatly promoted the use of QQ technology in bioreactors. Graphical