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Interfacial thermal resistance plays a critical role in heat dissipation, when the mean free paths of heat energy carriers approach or exceed the characteristic lengths of devices. Deep understanding on electron and phonon scattering, as well as their coupling behaviors are of importance for interfacial heat transport enhancement. In this work, complicated influential mechanisms of interface defects on phonon scattering are studied, from the aspects of both time‐domain thermoreflectance (TDTR) measurements and atomistic simulations. Particularly, this study focuses on the comprehensive influence of inelastic phonon scattering on interfacial thermal conductance (hK) of hexagonal and amorphous boron nitride (BN)/copper (Cu) interfaces with nonreactive and nondiffusive features. The TDTR results imply that the hK of Al/a‐BN/Cu is ≈80% higher than that of Al/h‐BN/Cu counterpart, with the comparable film thicknesses, grain sizes, and interface roughness. Although lower local strain near h‐BN/Cu interface can boost electron–phonon coupling, inelastic phonon scattering at a‐BN/Cu interface may greatly promote the interfacial heat transport. The authors believe multiple phonons scattering accompanied by high‐frequency phonons transformation to low‐frequency phonons within a‐BN may provide more phonon–phonon coupling channels at the a‐BN/Cu interface. The present findings may provide more insights to understand nanoscale heat transport mechanisms at metal/nonmetal interfaces.

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The poplar petiole gall aphid, Pemphigus populitransversus Riley, has been one of the major pests on cruciferous vegetable in the Rio Grande Valley (LRGV) of Texas since the late 1940s. It normally migrates from poplar trees to cruciferous vegetables in the fall, and migrates back to the trees in early spring of the coming year. Some root-feeding aphids were found on cruciferous vegetables in late spring and early summer in 1998 and the following years. Those aphids have been identified as Pemphigus obesinymphae Moran. This discovery completely changed the current knowledge about the root-feeding aphids on cruciferous vegetables in the LRGV. Due to their small size, morphological and feeding similarities between P. populitransversus and P. obesinymphae, their identification and distinction are difficult. In this study, random amplification of polymorphic DNA (RAPD) and amplified fragment length polymorphism (AFLP) were used to distinguish these two species over a period of time when the two species occurred together, or separately, in cabbage fields. The two species occurred on cabbage at different times of the year, and overlapped from October to June. From May to October, both species migrated to their primary hosts. The apterous aphids found on cabbage in winter contained mainly P. obesinymphae, whereas in early spring more apterous P. populitransversus were recovered. The root-feeding aphids would feed on cabbage plants as long as this host was available even during the hot, dry summer in the LRGV, although their populations were generally low. Both RAPD and AFLP techniques were efficient in discriminating the two species that showed obviously genetic variability. These molecular techniques confirmed the existence of the two aphid species in apterous samples collected from the soil in cabbage fields in the LRGV, and the results performed by RAPD were confirmed by AFLP. Furthermore, the results suggest that RAPD technique was a better choice despite its reproducibility problem, as it was less time-consuming and required less technology, labor and expense than AFLP.