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Abstract Point defects typically reduce the thermal conductivity (κ) of a crystal due to increased scattering of heat‐carrying phonons, a mechanism that is well understood and widely used to enhance or impede heat transfer in the material for different applications. Here an opposite effect is reported where the introduction of point defects in graphite with energetic particle irradiation increases its cross‐planeκby nearly a factor of two, from 10.8 to 18.9 W m K⁻¹at room temperature. Integrated differential phase contrast imaging with scanning transmission electron microscopy revealed the creation of spiro interstitials in graphite by the irradiation. The enhancement inκis attributed to a remarkable mechanism that works to the benefit of phonon propagation in both the harmonic and anharmonic terms: these spiro interstitial defects covalently bridge neighboring basal planes, simultaneously enhancing acoustic phonon group velocity and reducing phonon–phonon scattering in the graphite structure. The enhancement ofκreveals an unconventional role of lattice defects in heat conduction, i.e., easing the propagation of heat‐carrying phonons rather than impeding them in layered materials, inspiring their applications for thermal management in heavily radiative environments. 

Pesticide overuse has been an increasing concern in China. Digital technology, such as smartphone access, is considered an effective way to promote proper use of pesticides. Using the Chinese Extended Family Database (2015, 2017, and 2019), this study empirically examines the impact of smartphone access on pesticide use intensity among Chinese farmers. The results show a “double-edged sword” effect of smartphone access on pesticide use intensity. In rural areas with a low level of digital economy, greater smartphone access led to higher pesticide use intensity. In rural areas with a high digital economy level, smartphone access reduced pesticide use intensity. The study results show that reducing pesticide use intensity through digital technology is not a linear process but a complicated one that involves social and engineering integration, including an increase in access to smartphones, development of a regional digital economy, reconstruction of agricultural extension systems, and enhancement of the capacity of digital technology. 

Oxygen vacancies ( V O • • ) play a critical role as defects in complex oxides in establishing functionality in systems including memristors, all-oxide electronics, and electrochemical cells that comprise metal-insulator-metal or complex oxide heterostructure configurations. Improving oxide-oxide interfaces necessitates a direct, spatial understanding of vacancy distributions that define electrochemically active regions. We show vacancies deplete over micrometer-level distances in Nb-doped SrTiO 3 (Nb:SrTiO 3 ) substrates due to deposition and post-annealing processes. We convert the surface potential across a strontium titanate/yttria-stabilized zirconia (STO/YSZ) heterostructured film to spatial (<100 nm) vacancy profiles within STO using ( T = 500°C) in situ scanning probes and semiconductor analysis. Oxygen scavenging occurring during pulsed laser deposition reduces Nb:STO substantially, which partially reoxidizes in an oxygen-rich environment upon cooling. These results (i) introduce the means to spatially resolve quantitative vacancy distributions across oxide films and (ii) indicate the mechanisms by which oxide thin films enhance and then deplete vacancies within the underlying substrate.