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Repertoires of state-making and regime maintenance include the capture, control, and use of animals for activities ranging from landmine detection by rats to military incursions and border patrols on horseback. However, marine animals have been less amenable to efforts to fix or uphold states due to their disregard for territorial boundaries, thus prompting states to adopt different approaches. Through what means, then, do states incorporate marine animals into their resource and territorial claims? This research takes up this question through an examination of how the tourism industry in Ulsan, South Korea narrates its history of whaling and the geopolitical effects of this historiography. Ulsan is a former whaling hub and is now a centre of domestic whaling tourism. Building on resource nationalism and tourism geopolitics literature, we analyse the politics of Ulsan’s whale tourism through a combination of in-depth interviews, archival document analysis, and site observation. Our analysis reveals three interlinked sets of politics concerning the Bangudae Petroglyphs, Korean autonomy, and whales themselves. Korean state and non-state actors marshal prehistoric and historical whaling records in Ulsan to underscore cultural linkages and historical continuity between past and present-day Korean whaling practices. However, these nationalistic and territorialised descriptions of Korea’s relations with whales omit the highly consequential history of Japanese colonial whaling and its ongoing vestiges in postcolonial Korea. We find that the Korean government selectively mobilises ‘facts’ about the Bangudae Petroglyphs and Korean gray whales to support their whale resource claims within the International Whaling Commission. Moreover, whale tourism plays a crucial role in materially and discursively refining human-whale relations to bolster the state and city’s geopolitical positioning of whale resources and marine territory within the global whale governance landscape. [ABSTRACT FROM AUTHOR]

The van der Waals (vdW) heterojunctions of transition metal dichalcogenides (TMDCs) provide an advanced platform for interlayer exciton generation to detect the exceeding cutoff wavelengths of individual TMDCs. Herein, the first demonstration of high‐performance infrared (IR) photodetectors driven by interlayer excitons and based on HfS2/MoS2 vdW heterojunctions grown by chemical vapor deposition is presented. HfS2 exhibits selective growth only on MoS2, establishing a vertical heterojunction that effectively generates interlayer excitons. The synthesized HfS2/MoS2 vertical heterojunction with type‐II band alignment exhibits a low interlayer bandgap and a significantly large interface area, enabling highly efficient IR detection. Moreover, the built‐in potential in HfS2/MoS2 plays a pivotal role in the outstanding photoresponse by suppressing the dark current and providing gradient band bending for the interlayer exciton‐induced photocarriers to drift toward each electrode. The HfS2/MoS2 photodetector exhibits remarkable performance, achieving a detectivity (D*) of ≈7 × 1013 Jones at 1550 nm, D* of ≈2 × 1014 Jones at 980 nm, and fast response time of 60 µs, surpassing previously reported 2D photodetectors. Overall, the successful demonstration of a photodetector based on vdW epitaxial HfS2/MoS2 paves the way for the advancement of large‐scale high‐performance IR sensors. [ABSTRACT FROM AUTHOR]

Bacillus spores are highly resistant to toxic chemicals and extreme environments. Because some Bacillus species threaten public health, spore inactivation techniques have been intensively investigated. We exposed Bacillus atrophaeus spores to a 266 nm Nd:YVO4 laser at a laser power of 1 W and various numbers of scans. As a result, the UV laser reduced the viability of Bacillus atrophaeus spores. Although the outer coat of spores remained intact after UV laser irradiation of 720 scans, damage inside the spores was observed. Spore proteins were identified by matrix-assisted laser desorption/ionization Fourier transform ion cyclotron resonance mass spectrometry during the course of UV laser irradiation. Photochemical and photothermal processes are believed to be involved in the UV laser sterilization of Bacillus spores. Our findings suggest that a UV laser is capable of sterilizing Bacillus atrophaeus spores. [ABSTRACT FROM AUTHOR]

2D InSe is one of the semimetal chalcogenides that has been recently given attention thanks to its excellent electrical properties, such as high mobility near 1000 cm2 V−1 s−1 and moderate band gap of ≈1.26 eV suitable for IR detection. Here, high‐performance visible to near‐infrared (470–980 nm wavelength (λ)) photodetectors using surface‐doped InSe as a channel and few‐layer graphenes (FLG) as electrodes are reported, where the InSe top region is relatively p‐doped using AuCl3. The surface‐doped InSe photodetectors show outstanding performance, achieving a photoresponsivity (R) of ≈19 300 A W−1 and a detectivity (D*) of ≈3 × 1013 Jones at λ = 470 nm, and R of ≈7870 A W−1 and D* of ≈1.5 × 1013 Jones at λ = 980 nm, superior to previously reported 2D material‐based IR photodetectors operating without an applied gate bias. Surface doping using AuCl3 renders a band bending at the junction between the InSe surface and the top FLG contact, which facilitates electron‐hole pair separation and immediate photodetection. Multiple doped or undoped InSe photodetectors with different device structures are investigated, providing insight into the photodetection mechanism and optimizing performance. Encapsulation with hexagonal boron nitride dielectric also allows for 3‐month stability. [ABSTRACT FROM AUTHOR]

2D transition metal dichalcogenides (TMDCs) have emerged as promising candidates for post-silicon nanoelectronics owing to their unique and outstanding semiconducting properties. However, contact engineering for these materials to create high-performance devices while adapting for large-area fabrication is still in its nascent stages. In this study, graphene/Ag contacts are introduced into MoS 2 devices, for which a graphene film synthesized by chemical vapor deposition (CVD) is inserted between a CVD-grown MoS 2 film and a Ag electrode as an interfacial layer. The MoS 2 field-effect transistors with graphene/Ag contacts show improved electrical and photoelectrical properties, achieving a field-effect mobility of 35 cm 2 V -1 s -1 , an on/off current ratio of 4 × 10 8 , and a photoresponsivity of 2160 A W -1 , compared to those of devices with conventional Ti/Au contacts. These improvements are attributed to the low work function of Ag and the tunability of graphene Fermi level; the n-doping of Ag in graphene decreases its Fermi level, thereby reducing the Schottky barrier height and contact resistance between the MoS 2 and electrodes. This demonstration of contact interface engineering with CVD-grown MoS 2 and graphene is a key step toward the practical application of atomically thin TMDC-based devices with low-resistance contacts for high-performance large-area electronics and optoelectronics., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)