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Maneuverability, which is closely related to navigation safety, is an important part of the overall performance of an underwater vehicle. The purpose of this study is to analyze the dynamic response of an underwater vehicle to internal waves at different angles and speeds. A combination of experiments and numerical simulations is used to compare the forces on the underwater vehicle. In terms of fluid-structure coupling, the internal wave interface is tracked by the VOF method. In this paper, waves of the same amplitude ratio as the numerical results are simulated using a wave-making sphere. The validity of the numerical method is verified by comparing with the rotation moment test of the underwater vehicle. The results show that different angles of attack have significant effects on the forces and moments of the underwater vehicle and that choosing the right angle of attack and rotation speed can limit the dangerous depth. The conclusion is of certain significance for the safety of underwater navigation.

The Nanmushu carbonate-hosted Zn-Pb deposit is located in the Mayuan district of Shaanxi Province, a newly discovered metallogenic district next to the Sichuan Basin, in the northern margin of the Yangtze Block, which is the largest and the only one that is currently mined in this district. The δ34S values of sulfides are characterized by positive values with a peak around +18‰, and the reduced sulfur may have derived from reduction of SO42- from paleoseawater or evaporitic sulfates that have possibly been leached by basinal brines during mineralization stage. Detailed fluid inclusion study shows two types of fluids in the sphalerite, quartz, dolomite, calcite and barite, that is, aqueous-salt dominant inclusions (type I) and hydrocarbon-bearing inclusions (type II). The Laser Raman spectroscopy study shows occurrence of certain amount of CH4, C4H6, and bitumen. The salinities show similar values around 6 to 12 wt% NaCl equivalent but a decreasing temperature from early to late stages (typically 200° to 320°C in stage I, 180° to 260°C in stage II, and 140° to 180°C in stage III). These features may be related to basinal brines mixing between an external higher salinity CaCl2 ± MgCl2-rich fluid and a local H2O-NaCl methane-rich fluid.

With the spread and persistence of COVID-19, pharyngeal swab sampling, is an important link in nucleic acid testing, which is characterized by a high workload and susceptibility to infection. Therefore, it is necessary for medical workers to use medical robots instead of manual site sampling for collaborative sampling. However, the traditional teleoperation has difficulty ensuring the closed-loop performance due to the delay of the actual process, along with the weak control performance; Moreover, a robot cannot accurately plan and track sampling paths due to sensor accuracy and the changes in patient pharyngeal posture. The paper proposes a human-robot shared control strategy based on intention estimation, introducing the human intention as a reference, and the operator and robot work together to solve various significant problems during sampling. The human-robot negotiation based on the method includes the human judgement and perception and the robot into the invasion task. Through, the shared control based on the operator intention estimation, the robot can operate the obstacle avoidance and approach the target contact point remotely. Finally, two kinds of experiments of invasion process of throat swab sampling are implemented: a static target invasive experiment and a dynamic target invasive experiment, aiming at two different sampling conditions. Compared with the robotic independent control sampling, the time consumption in the two experiments is reduced by 34.8% and 41.6%, respectively, and the ultimate target position is basically within the scope of sampling field (where the range of the posterior pharynx wall < 20 mm). Thus, the sampling rate can reach 100%. Compared with independent control sampling by humans, the time consumption of the two experiments is respectively reduced by 15.9% and 42.3% on average, and the target position accuracy and sampling rate are quite close. Experimental results show that the control strategy improves the speed, flexibility, and intelligence of task execution compared to common sampling methods, laying the foundation for low-cost human-robot collaborative sampling. [ABSTRACT FROM AUTHOR]

Anode‐free Li metal batteries (AFLMBs) are highly advantageous due to their high energy density, low cost, and simple fabrication. However, severe challenges, such as uncontrolled dendrite formation and low coulombic efficiency, restrict their practical application. Herein, this work introduces a silver nanoparticles incorporated p‐doped conjugated polymer (Ag‐PCP) wetting agent on the copper current collector, which promotes both uniform Li nucleation and rapid formation of a LiF‐rich solid electrolyte interphase (SEI) at the early stage, resulting in interfacial stabilization and high Li utilization efficiency. Moreover, this work verifies the interfacial fluorinated mechanism of the Ag‐PCP to efficiently achieve a favorable SEI chemistry, which serves as an intermediate process for promoting LiF formation. Benefiting from the synergistic effect of Ag–Li alloying and F‐doping chemistry of the Ag‐PCP chains, the deposited Li exhibits a compact column‐like structure with dendrite‐free morphology, and the anode‐free cells display superior cycling stability with long lifespan even under harsh conditions, with the LFP//Ag‐PCP│Cu full cell having a high capacity retention of 72% (Li inventory retention rate, 99.8%) at 1 C‐rate after 200 cycles. [ABSTRACT FROM AUTHOR]

Electrolyte‐gated transistors (EGTs) have been extensively studied as a next‐generation neuromorphic device mimicking the biological ionic flux in synapses. However, its long‐term plasticity characteristic lasts only for few seconds because of the rapid self‐discharge of electrical double layer. Here, ultraviolet ozone (UVO) treated water‐in‐bisalt (WiBS)/polymer electrolyte‐gated synaptic transistor (WEST) which excellently implements multiple synaptic functions is proposed. Ultraviolet (UV) light and reactive oxygen radicals generated during UVO treatment form trap sites on the surface of active layer, causing lithium cations in the WiBS/polymer electrolyte to be captured at the electrolyte/active layer interface. The UVO treated WEST shows enhanced nonvolatile memory performance for 10 000 s, up to 1186 times longer than that of the untreated WEST. Also, near‐ideal weight update over 10 000 cycle tests with 0.32 and −0.55 nonlinearities of long‐term potentiation and depression is acquired with a ten times improved symmetricity. These results confirm that the surface engineering is a key technique for sophisticated ion transport, and demonstrate various applicability of EGTs as a neuromorphic device. [ABSTRACT FROM AUTHOR]

Interfacial instability between Li‐metal anode (LMA) and inorganic solid‐state electrolyte (SSE) is a critical issue in all‐solid‐state Li‐metal batteries (ASSLBs). Previous studies have focused on interface modification methodology to achieve long‐term cycling stability in ASSLBs. However, strategy establishment without an in‐depth understanding of the LMA–SSE interface is limited to a phenomenological solution. Also, the fact that rechargeable batteries are operated by behavior of charges inside electric field is frequently overlooked. Here, it is demonstrated for the first time that interface modeling based on energy band theory does effectively overcome the intrinsic vulnerability of SSE to LMA. The interfacial deterioration, due to undesirable electron transport from LMA to the SSE surface, is precluded by a titanium compound self‐induced interlayer (TSI), which forms an interfacial energy barrier. The Li symmetric cell with a TSI successfully maintains its constant overpotential over 1000 cycles and the significantly reduced impedance, whereas the cell having no interface modification exhibits erratic voltage profiles and is easily failed by repetitive charge–discharge process. This newly introduced approach is an informative tool to substantially reinforce the fundamental understanding of interfacial phenomena in all‐solid‐state batteries. Furthermore, rigorous stability requirements of automotive applications are expected to be fulfilled by the innovative interface modification. [ABSTRACT FROM AUTHOR]

As an important medium of human-computer interaction, flexible tactile sensors have a vital influence on the intelligence and safety of a system by accurately identifying the contact position and force. For now, most of the existing flexible capacitive pressure sensors adopt an array structure, which still cannot meet the requirements including simple manufacturing, simple wiring, and low cost. This paper innovatively proposes a flexible array-less capacitive tactile sensor, a 30 mm $\times30$ mm sensor prototype, consisting of flexible electrodes and a dielectric layer of a polydimethylsiloxane (PDMS) and multiwalled carbon nanotube (MWCNT) composite. Under the action of a contact force, the contact area is deformed, resulting in a capacitance change in the flexible sensor. First, Poisson’s equation is used to determine the relationship between the electric potential and position. Then, elastic contact mechanics is adopted to describe the relationship between the electric charges and force. Finally, the contact position and force are recognized by measuring the change in capacitance in real time, based on the classical principle of capacitance. Simulation and experimental results verified the effectiveness of the proposed recognition method, showing that the recognition resolution of contact position can reach $500\,\,\mu \text{m}\,\,\times 100\,\,\mu \text{m}$ , and the accuracy of contact force is 95.85%. Theoretically, the proposed flexible array-less sensor in this paper has infinite spatial resolution, and most importantly, it does not rely on complex manufacturing, redundant circuits, or sensor cell arrays. Therefore, it has broad application prospects in related fields such as electronic skin and wearable electronic devices. [ABSTRACT FROM AUTHOR]

In this paper, a novel kinematics model based on segmented variable curvature (SVC) method is proposed to describe the deformation of soft manipulator under the condition of environmental contact. Firstly, the variable curvature (VC) framework is used to the spatial backbone curve, which is to discrete the soft manipulator into tangent arcs with different curvatures. When the contacts with surroundings occur, the contacted arcs are further divided into several separate sub-segments at the contact points. Then, combining kinematics and statics of all the segments, the model of soft manipulator is established under environmental constraints. The proposed model inherits the generality of the continuous VC method, and resolves the complex contact problem with environmental constraints. Finally, simulations and experiments are conducted to verify the effectiveness of the proposed SVC method under contact conditions. The results show that compared with the traditional VC method the proposed model can obtain higher accuracy in describing contact segment deformation under contact constraints without knowing the contact force in advance. [ABSTRACT FROM AUTHOR]

Li Metal Anodes: Nonwoven rGO Fiber-Aramid Separator for High-Speed Charging and Discharging of Li Metal Anode (Adv. Keywords: functional separators; Li metal anodes; Li metal batteries; reduced graphene oxide; SEI layers; solid electrolyte interphase EN functional separators Li metal anodes Li metal batteries reduced graphene oxide SEI layers solid electrolyte interphase 1 1 1 07/23/20 20200701 NES 200701 In article number 2001479, Sang Yoon Park, Jeeyoung Yoo, Youn Sang Kim and co-workers develop an advanced Li metal anode, by introducing reduced graphene oxide (rGO) fibers with aramid paper as a conductive frame which helps a solid electrolyte intherphase (SEI) layer to grow stably in the confined fibers structure. Functional separators, Li metal anodes, Li metal batteries, reduced graphene oxide, SEI layers, solid electrolyte interphase. [Extracted from the article]

Recently, organic compounds are considered as promising candidates for application in next-generation energy storage systems to overcome the disadvantages of conventional inorganic cathode materials, including their low specific capacity and poor disposal systems. In particular, pillar[5]quinone (P5Q) is very effective as it provides active sites that favor Li uptake and promote a high theoretical capacity. Herein, we propose P5Q-derived cathodes, which are enveloped in multi-walled carbon nanotubes and cellulose nanofibers (CNFs), fabricated by a simple vacuum-filtering method. The designed cathode solves the issues associated with organic materials, including their high solubilities in aprotic electrolytes and low conductivities. Furthermore, CNFs are introduced as alternatives to conventional polyolefin separators. CNF separators can effectively suppress the dissolution of active materials in liquid electrolytes. In addition, CNFs improve ionic conductivity (0.88 mS cm−1), electrolyte wettability (electrolyte uptake: 333.41%, porosity: 70 ± 5%), and thermal shrinkage in contrast to conventional polyolefin separators. The Li-ion battery, assembled with the suggested P5Q cathode and CNF separator, exhibits highly stable capacity retention (76.5% after 50 cycles at a 0.2 C rate) and good rate capability, although an organic electrolyte is used. [ABSTRACT FROM AUTHOR]

Li metal, which has a high theoretical specific capacity and low redox potential, is considered to the most promising anode material for next‐generation Li ion‐based batteries. However, it also exhibits a disadvantageous solid electrolyte interphase (SEI) layer problem that needs to be resolved. Herein, an advanced separator composed of reduced graphene oxide fiber attached to aramid paper (rGOF‐A) is introduced. When rGOF‐A is applied, F− anions, generated from the decomposition of the LiPF6 electrolyte during the SEI layer formation process form semi‐ionic CF bonds along the surface of rGOF. As Li+ ions are plated, the "F‐doped" rGO surface induces the formation of LiF, which is known as a component of a chemically stable SEI, therefore it helps the Li metal anode to operate stably at a high current of 20 mA cm−2 with a high capacity of 20 mAh cm−2. The proposed rGOF‐A separator successfully achieves a stable SEI layer that could resolve the interfacial issues of the Li metal anode. [ABSTRACT FROM AUTHOR]

The Wusihe carbonate-hosted Zn-Pb deposit (3.7 Mt. Zn + Pb at a grade of 8.6% Zn and 2.0% Pb) is the largest deposit in the Dadu River Valley district of the Sichuan-Yunnan-Guizhou metallogenic province of southwest China. Three types of orebodies occur: (1) stratiform, banded and lamellar, within dolomite of the Neoproterozoic Dengying Formation; (2) vein type; and (3) breccia type. Four stages of mineralization are distinguished: (i) pyrite stage, (ii) pyrite-pyrrhotite-galena-sphalerite-bitumen stage, (iii) sphalerite-galena stage, and (iv) bitumen-calcite stage. Sphalerite and galena from stages II and III show δ34S ranges from +7.1 to +9.7‰ and +9.1 to +13.1‰, respectively. High-precision in situ lead isotope analyses of sulfides show 208Pb/204Pb, 207Pb/204Pb, and 206Pb/204Pb ratios of 37.938 to 38.336, 15.579 to 15.682, and 17.951 to 18.195, respectively, which suggest a mixing of lead from the basement and the host rocks. Rb-Sr isotope analyses for six sphalerite samples of stage II yielded an isochron age of 411 ± 10 Ma (MSWD = 1.4). Combining all available ore geology and geochemical data, together with fluid inclusion data reported previously, we suggest that the Wusihe deposit is a Mississippi Valley-type (MVT) deposit. [ABSTRACT FROM AUTHOR]

Lithium metal is one of the most attractive anode materials, due to its high theoretical specific capacity and lowest electrochemical potential. However, low coulombic efficiency and serious safety hazards have still hindered the wide applications of next-generation batteries including Li–S and Li–air. Previous studies have suggested overcoming the problem by applying various structures of current collectors. These structures homogenize the Li ion flux or provide space for volume expansion. However, there are some limitations to solving problems occurring at the Li metal surface, because the current collector is underneath the structures of Li metal. In this work, we propose a facile and cost-effective strategy for stabilizing the lithium metal–electrolyte interface via a three-dimensional stainless steel mesh (SSM) interlayer. Its high specific surface area lowers the local current density and provides an electronic flow path for dead Li. Also, this structure leads to confinement of Li deposits and alleviates volume expansion. As a result, the Li anode with the SSM interlayer operated at current densities of 1 mA cm−2 (1C rate) and 5 mA cm−2, and it exhibited a longer cycle-life than planar structures in a symmetrical cell configuration. [ABSTRACT FROM AUTHOR]