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Abstract We show that a minimum-mass neutron star undergoes delayed explosion after mass removal from its surface. We couple the Newtonian hydrodynamics to a nuclear reaction network of ∼4500 isotopes to study the nucleosynthesis and neutrino emission during the explosion. An electron antineutrino burst with a peak luminosity of ∼3 × 10⁵⁰erg s⁻¹is emitted while the ejecta is heated to ∼10⁹K. A robustr-process nucleosynthesis is realized in the ejecta. Lanthanides and heavy elements near the second and thirdr-process peaks are synthesized as end products of nucleosynthesis, suggesting that subminimal neutron star explosions could be an important source of solar chemical elements. 

Abstract. New particle formation (NPF) and subsequent particle growth are importantsources of condensation nuclei (CN) and cloud condensation nuclei (CCN).While many observations have shown positive contributions of NPF to CCN atlow supersaturation, negative NPF contributions were often simulated inpolluted environments. Using the observations in a coastal city of Qingdao,Beijing, and Gucheng in north China, we thoroughly evaluate the simulatednumber concentrations of CN and CCN using an NPF-explicit parameterizationembedded in the WRF-Chem model. For CN, the initial simulation shows largebiases of particle number concentrations at 10–40 and 40–100 nm. Byadjusting the process of gas–particle partitioning, including the massaccommodation coefficient (MAC) of sulfuric acid, the phase changes in primary organic aerosol emissions, and the condensational amount of nitric acid, the improvement of the particle growth process yields substantially reduced overestimation of CN. Regarding CCN, secondary organic aerosol (SOA) formed from the oxidation of semi-volatile and intermediate-volatility organic compounds (S/IVOCs) is called SI-SOA, the yield of which is an important contributor. At default settings, the SI-SOA yield is too high without considering the differences in precursor oxidation rates. Lowering the SI-SOA yield under linear H2SO4 nucleation scheme results in much-improved CCN simulations compared to observations. On the basis of the bias-corrected model, we find substantially positive contributions of NPF to CCN at low supersaturation (∼ 0.2 %) over broad areas of China, primarily due to competing effects of increasing particle hygroscopicity, a result of reductions in SI-SOA amount, surpassing that of particle size decreases. The bias-corrected model is robustly applicable to other schemes, such as the quadratic H2SO4 nucleation scheme, in terms of CN and CCN, though the dependence of CCN on SI-SOA yield is diminished likely due to changes in particle composition. This study highlights potentially much larger NPF contributions to CCN on a regional and even global basis. 

Excitons in monolayer semiconductors have a large optical transition dipole for strong coupling with light. Interlayer excitons in heterobilayers feature a large electric dipole that enables strong coupling with an electric field and exciton-exciton interaction at the cost of a small optical dipole. We demonstrate the ability to create a new class of excitons in hetero- and homobilayers that combines advantages of monolayer and interlayer excitons, i.e., featuring both large optical and electric dipoles. These excitons consist of an electron confined in an individual layer, and a hole extended in both layers, where the carrier-species–dependent layer hybridization can be controlled through rotational, translational, band offset, and valley-spin degrees of freedom. We observe different species of layer-hybridized valley excitons, which can be used for realizing strongly interacting polaritonic gases and optical quantum controls of bidirectional interlayer carrier transfer. 

Lightweight and strong structural materials attract much attention due to their strategic applications in sports, transportation, aerospace, and biomedical industries. Nacre exhibits high strength and toughness from the brick-and-mortar–like structure. Here, we present a route to build nacre-inspired hierarchical structures with complex three-dimensional (3D) shapes by electrically assisted 3D printing. Graphene nanoplatelets (GNs) are aligned by the electric field (433 V/cm) during 3D printing and act as bricks with the polymer matrix in between as mortar. The 3D-printed nacre with aligned GNs (2 weight %) shows lightweight property (1.06 g/cm 3 ) while exhibiting comparable specific toughness and strength to the natural nacre. In addition, the 3D-printed lightweight smart armor with aligned GNs can sense its damage with a hesitated resistance change. This study highlights interesting possibilities for bioinspired structures, with integrated mechanical reinforcement and electrical self-sensing capabilities for biomedical applications, aerospace engineering, as well as military and sports armors. 

Interlayer exciton diffusion in transition metal dichalcogenide heterostructures is controlled by the moiré potential. 

Abstract Flexible sensors with accurate detection of environmental stimuli (e.g., humidity and chemical substances) have drawn increasing research interests in biomedical engineering and environmental science. However, most work is focused on isotropic sensing of liquid occurrence due to the limitation of material development, sensor design, and fabrication capability. 3D printing is used to build multifunctional flexible liquid sensors with multimaterials enabling anisotropic detection of microliquid droplets, and described herein. Electrical conductive composite hydrogels capable of detecting chemical liquid are developed with poly (ethylene diacrylate) (PEGDA) and multiwalled carbon nanotube (MWCNT). Due to the absorption of the liquid droplet and related swelling behavior, the resistance of PEGDA/MWCNT composite hydrogel increases dramatically, while the resistance of pure PEGDA hydrogel decreases significantly. Based on the two composite hydrogels and the related 3D printing method, a mesh‐shaped liquid sensor that can effectively identify the position and volume of liquid leakage in a short time is developed. Furthermore, a three‐layered liquid sensor to enable bidirectional monitor and detection of the liquid leakage in two different sides is demonstrated. The 3D‐printed liquid sensor offers a distinctive perspective on the potential applications in various fields for detection of liquid leakage in accurate position and direction. 

Abstract The semiconductor tracker (SCT) is one of the tracking systems for charged particles in the ATLAS detector. It consists of 4088 silicon strip sensor modules.During Run 2 (2015–2018) the Large Hadron Collider delivered an integrated luminosity of 156 fb -1 to the ATLAS experiment at a centre-of-mass proton-proton collision energy of 13 TeV. The instantaneous luminosity and pile-up conditions were far in excess of those assumed in the original design of the SCT detector.Due to improvements to the data acquisition system, the SCT operated stably throughout Run 2.It was available for 99.9% of the integrated luminosity and achieved a data-quality efficiency of 99.85%.Detailed studies have been made of the leakage current in SCT modules and the evolution of the full depletion voltage, which are used to study the impact of radiation damage to the modules.