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It is quite a challenge to obtain the temperature and species concentration fields of muzzle flash at high noise level. In this numerical study, radiation intensity of muzzle flash received by the high-speed Complementary Metal-Oxide-Semiconductor (CMOS) camera was simulated based on the line-of-sight method in the direct radiative transfer problem. The inverse radiative transfer problem of reconstructing distributions of temperature and soot volume fraction from the knowledge of flame radiation intensity was transformed into a minimization optimization problem and a meta-heuristic algorithm was used to solve the problem. The effects of the number of detection lines, optical thickness and measurement errors on the reconstruction results were discussed in details. A method to estimate the noise level of radiation intensity was developed, experimental results showed that the signal-to-noise ratio ( SNR ) of radiation intensity can be successfully inferred when the SNR is greater than 20 dB. Subsequently, prior knowledge of the noise level was introduced in the regularization to achieve a meaningful approximation of the exact value. The reconstruction of the soot volume fraction filed with SNR greater than 40 dB is considered successful with the inclusion of an appropriate regularization term in the objective function, and the reconstruction of the temperature field is feasible even with SNR as low as 15 dB. The high tolerance to the noise level of the radiation intensity gives the reconstruction algorithm the potential to be used in practical experiments of muzzle flash.

The role of the mid‐latitude seaway between the proto‐Paratethys and the North Sea on the early Paleogene ocean circulation is examined with a state‐of‐art earth system model. The early Eocene simulations here demonstrate that the open mid‐latitude seaway captures most relatively fresh surface water from the Arctic and Greenland‐Norwegian Sea and prohibits them from leaking into the Labrador Sea, thus benefiting the Atlantic meridional overturning circulation (AMOC). However, the closure of the seaway triggers the AMOC reduction as more relatively fresh surface water enters the Labrador Sea, and the AMOC finally shuts down. Together with geological reconstructions, our results also provide insights into understanding the evolution of the Atlantic‐Arctic oceanic gateways during the Paleogene. Plain Language Summary Recent geological evidence demonstrated that a mid‐latitude seaway connected the proto‐Paratethys sea and the North Sea during the early Eocene. Then, this connection was closed since the late Eocene‐early Oligocene. Here, using climate modeling, we investigated the effects of this mid‐latitude seaway evolution, particularly in modulating the Atlantic meridional overturning circulation (AMOC). Our simulations show that the open seaway prohibits the relatively fresh Arctic surface water from leaking into the Labrador Sea and thus favors the formation of AMOC. On the contrary, the closed seaway allows more relatively fresh Arctic surface water to influence the Labrador Sea, thus triggering the AMOC reduction. Our study pinpoints a controlling role of the mid‐latitude seaway in modulating global ocean circulation during the early Paleogene. Key Points The evolution of the mid‐latitude seaway in the early Paleogene influences ocean circulation The opening of the seaway favors the Atlantic meridional overturning circulation (AMOC), while its closing leads to AMOC shutdown

During the early Paleogene, the Arctic Ocean existed in a warm yet restricted freshwater regime, with episodic strong freshening leading to proliferation of the freshwater‐adapted Azolla at basal middle Eocene times (49–48 Ma). The Kara Strait, located between the Arctic Ocean and the West Siberian Sea (WSS), facilitated an open central Eurasian seaway before the middle Eocene and the temporal coincidence of the strait's initial closure with the Azolla expansion suggests a causal link. Here with numerical modeling, we demonstrate that the open central Eurasian seaway constitutes a conveyor for heat and salt transport from subtropical to high‐latitude waters, accompanied by wind‐induced northward currents through the WSS. The closure of the Kara Strait disrupts this poleward transport, leading to cooling and freshening of both the Arctic Ocean and the WSS. The resultant decline in Arctic surface salinities might have favored the Azolla Event. Plain Language Summary During the greenhouse climate of the early Paleogene (56–49 Ma), the Arctic was much warmer and wetter than today, with substantially reduced sea surface salinities. Moreover, the strong freshening episode at the basal middle Eocene (∼49 Ma) brought about the flourishing of freshwater fern Azolla, known as the Azolla Event. Geological observations indicate temporal coincidence of the initial closure of the Kara Strait with the Azolla expansion, which may imply a causal relationship between them. Here with numerical modeling, we demonstrate that an open Kara Strait enables an active poleward heat and salt transport through the central Eurasian Seaway. This is achieved by wind‐induced northward currents from subtropical to polar regions. However, when the Kara Strait is closed, the Arctic inflow ceases, and the currents within the central Eurasian seaway are redistributed. The modulated flow field leads to cooling and freshening of both the Arctic Ocean and the West Siberian Sea. The resultant low Arctic surface salinities approach the upper limit for sustaining Azolla growth and might have favored the Azolla Event during the earliest middle Eocene. Key Points The open central Eurasian seaway constitutes a heat and salt conveyor from subtropical to high‐latitude waters during the early Paleogene Closure of the Kara Strait leads to strong freshening of the Arctic surface and might favor the Azolla bloom at basal middle Eocene times

Brain-inspired neuromorphic computing, featured by parallel computing, is considered as one of the most energy-efficient and time-saving architectures for massive data computing. However, photonic synapse, one of the key components, is still suffering high power consumption, potentially limiting its applications in artificial neural system. In this study, we present a BP/CdS heterostructure-based artificial photonic synapse with ultra-low power consumption. The device shows remarkable negative light response with maximum responsivity up to 4.1 × 108 A W−1 at VD = 0.5 V and light power intensity of 0.16 μW cm−2 (1.78 × 108 A W−1 on average), which further enables artificial synaptic applications with average power consumption as low as 4.78 fJ for each training process, representing the lowest among the reported results. Finally, a fully-connected optoelectronic neural network (FONN) is simulated with maximum image recognition accuracy up to 94.1%. This study provides new concept towards the designing of energy-efficient artificial photonic synapse and shows great potential in high-performance neuromorphic vision systems.Energy-efficient artificial photonic synapse is designed based on photo-sensitive BP/CdS heterostructure device, which can be used for high-performance brain-inspired neuromorphic computing.

Chlorine, a crucial basic chemical, is primarily produced by the electrolysis of chloride-containing brines, a highly energy-intensive process with a substantial carbon footprint. Notably, concentrated chloride-containing brines, e.g., acidic wastewater, desalination wastewater, seawater, possess significant osmotic energy, which can be harnessed using membrane-based diffusion cells. Considering this, we here present a spontaneous chlorine production method by using the inherent energy and chloride ions present in these brines. The method is first demonstrated with simulated acidic wastewater because in industry, diffusion cells are already widely used to recycle waste acid. Sulfonated covalent-organic framework membranes are employed to facilitate the diffusion of protons and reject multi-valent cations, purifying acid and avoiding side reactions on the anodes. Consequently, our method simultaneously recovers acid, produces hydrogen and chlorine without consuming external energy. We also validate the general applicability of the method with simulated desalination wastewater. Since our method is compatible with the diffusion-based industrial processes, it holds significant promise for facile, scalable implementation. We also expect the method to be extended for the spontaneous production of other crucial chemicals such as ammonia from nitrate-containing brines. Researchers report a spontaneous method that produces chlorine directly from chloride-containing brines by harnessing their inherent osmotic energy and chloride ions, without any external energy input.

Logic-in-memory architectures could be used to develop efficient computing devices with low power consumption. However, the approach is limited by device performance issues, including reliability and versatility. Here we report a two-dimensional van der Waals heterostructure device that can function as both reconfigurable transistor and reconfigurable non-volatile memory, as well as provide reconfigurable logic-in-memory capabilities. The architecture of the device—termed a partial floating-gate field-effect transistor—offers both charge-trapping and field-regulating units. When operating as a transistor, the device can be switched between the p- and n-type mode, and exhibits a subthreshold swing of 64 mV dec –1 and on/off current ratio approaching 10 8 . When operating as a memory, the device can be switched between the p- and n-type memory, and exhibits an erase/program ratio approaching 10 8 . We use the devices to fabricate complementary metal–oxide–semiconductor circuits, and linear and nonlinear logic gates with in situ storage, as well as device-efficient half-adder circuits. A van der Waals heterostructure that has a partial floating-gate field-effect transistor device architecture can function as both reconfigurable transistor and reconfigurable non-volatile memory, and can provide reconfigurable logic-in-memory capabilities.

Achieving a balance of good thermal stability, high performance, and appropriate sensitivity in materials remains a primary research goal in energetic materials. In this study, a series of dinitrimine-functionalized tris-1,3,4-oxadiazole-based energetic compounds was synthesized. Dinitroimmine 5 was found to possess favorable thermal stability (Td = 180 °C), superior mechanical sensitivity (IS = 25 J, FS = 240 N), and good detonation velocity (vD = 8372 m s−1). These results suggest that this polyheterocyclic backbone structure facilitates the synthesis of high-performance energetic compounds with application potentials.

Optoelectronic synaptic elements are emerging functional devices for the vigorous development of advanced neuromorphic computing technology in the post-Moore era. However, optoelectronic devices based on transition metal dichalcogenides (TMDs) are limited to their poor mobilities and weak light-matter interactions, which still hardly exhibit superior device performances in the application of artificial synapses. Here, we demonstrate the successful fabrication of Au nanoparticle-coupled MoS 2 heterostructures via chemical vapor deposition (CVD), where the light absorption of MoS 2 is greatly enhanced and engineered by plasmonic effects. Hot electrons are excited from Au nanoparticles, and then injected into MoS 2 semiconductors under the light illumination. The plasmonically-engineered photo-gating effect at the metal-semiconductor junction is demonstrated to create optoelectronic devices with excellent synaptic behaviors, especially in ultra-sensitive excitatory postsynaptic current (EPSC, 9.6 × 10 −3 nA@3.4 nW·cm −2 ), ultralow energy consumption (34.7 pJ), long-state retention time (> 1,000 s), and tunable synaptic plasticity transitions. The material system of Au-nanoparticles coupled TMDs presents unique advantages for building artificial synapses, which may lead the future development of neuromorphic electronics in optical information sensing and learning.

During the Cretaceous, there were two factors that had important influences on the East Asian climate, the East Asian coastal mountains and Earth's orbital cycling. An important question is how the coastal mountains modulated the variability of East Asian climate over orbital timescales. Here, we perform simulations with the coastal mountains of 0, 2, and 4 km high and three orbital configurations to answer the question. Our results show that a mountain range at the East Asian coast can amplify the impacts of orbital forcing on East Asian climate. Specifically, precipitation over the Songliao Basin in Northeastern China has significant changes as the coastal mountain range is about 4 km high. Combining our simulation results with orbitally‐controlled sedimentary deposits from the Songliao Basin, we conclude that the altitude of the coastal mountain range was very likely higher than 2 km in the Late Cretaceous. Plain Language Summary Tectonic events and solar insolation are the two important factors impacting variations of the climate system in the geological past. Regional climate responses to variations in the radiation from the sun over 104–105 years were often magnified or dampened by tectonic events. Cretaceous sedimentary records in East Asia suggest that East Asian climate was influenced by the solar insolation. Geological evidence showed that a mountain range existed along the East Asian coast then. Would this mountain range modulate impacts of solar insolation on East Asian climate? Our modeling results show that the influence of solar insolation on East Asian climate can be amplified by the coastal mountain range, depending on the mountain elevation. When the coastal mountain range is ∼2 km high, the amplification effects become significant. When its altitude reaches ∼4 km, the response of East Asian climate to solar insolation is considerably strengthened, and such a condition is supported by the rhythm induced by the climate variation due to solar insolation archived in the Cretaceous strata in the Songliao Basin. Thus, we speculate that the East Asian coastal mountains might have reached an altitude more than 2 km in the Late Cretaceous. Key Points East Asian climate was sensitive to orbital forcing in the Late Cretaceous East Asian coastal mountains amplified orbital forcing on East Asian climate variability East Asian coastal mountains were likely higher than 2 km in the Late Cretaceous

Optoelectronic synaptic devices integrating light‐perception and signal‐storage functions hold great potential in neuromorphic computing for visual information processing, as well as complex brain‐like learning, memorizing, and reasoning. Herein, the successful growth of MoS2 monolayer arrays assisted by gold nanorods guided precursor nucleation is demonstrated. Optical, spectral, and morphology characterizations of MoS2 prove that arrayed flakes are homogeneous monolayers, and they are further fabricated as optoelectronic devices showing featured photocurrent loops and stable optical responses. Typical synaptic behaviors of photo‐induced short‐term potentiation, long‐term potentiation, and paired pulse facilitation are recorded under different light stimulations of 450, 532, and 633 nm lasers at various excitation powers. A visual sensing system consisting of 5 × 6 pixels is constructed to simulate the light‐sensing image mapped by forgetting curves in real time. Moreover, the system presents the ability of utilizing associated images to restore vague and incomplete memories, which successfully mimics human intelligent behaviors of association memory and logical reasoning. The work emulates the brain‐like artificial intelligence using arrayed 2D semiconductors, which paves an avenue to achieve smart retina and complex brain‐like system. The growth of MoS2 monolayer arrays assisted by gold nanorods is demonstrated. Arrayed devices present the ability of utilizing associated images to restore vague and incomplete memories, which successfully mimics human intelligent behaviors. The work emulates the brain‐like artificial intelligence using arrayed 2D semiconductors, which paves an avenue to achieve smart retina and complex brain‐like system.