In order to imitate brain-inspired biological information processing systems, various neuromorphic computing devices have been proposed, most of which were prepared on rigid substrates and have ...energy consumption levels several orders of magnitude higher than those of biological synapses (∼10 fJ per spike). Herein, a new type of wearable organic ferroelectric artificial synapse is proposed, which has two modulation modes (optical and electrical modulation). Because of the high photosensitivity of organic semiconductors and the ultrafast polarization switching of ferroelectric materials, the synaptic device has an ultrafast operation speed of 30 ns and an ultralow power consumption of 0.0675 aJ per synaptic event. Under combined photoelectric modulation, the artificial synapse realizes associative learning. The proposed artificial synapse with ultralow power consumption demonstrates good synaptic plasticity under different bending strains. This provides new avenues for the construction of ultralow power artificial intelligence system and the development of future wearable devices.
We report a comparative study of the negative capacitance (NC) Ge pFETs with HfZrO x (HZO) partially and fully covering gate region. Utilizing the layout with HZO partially covering the gate, the ...internal voltage gain dV int /dV GS > 10 is demonstrated in NC Ge pFETs, which is attributed to the NC effect induced by HZO film. NC transistor demonstrates the hysteresis above 2 V, the sub-60 mV/decade subthreshold swing, and the improved drive current over internal-gated MOSFET. As the area of HZO is increased to fully cover the gate, the increased ferroelectric capacitance C FE produces the much better capacitance matching between C FE and the MOS capacitance of TaN/HfO 2 /Ge channel, contributing to the elimination of hysteresis of the NC Ge pFET. NC Ge pFETs with the gate fully covered by HZO achieve a much higher gate capacitance peak and a 36% enhancement in drive current compared to the devices with HZO partially covering gate.
Russian dolls: Two covalently tethered, curved bispyridinyl ligands and PdII ions have been shown to self‐assemble into a sphere‐in‐sphere complex (6.3 nm in diameter; see X‐ray structure). The two ...ligands did not form heteroleptic mixed complexes, but instead assembled into two distinct homogeneous M12L24 cuboctahedra, reminiscent of a double‐shell viral capsid.
To set up a rapid real-time nondestructive detection of moisture content, this paper reported the results of a combination of LF-NMR and BP-ANN to monitor the relationship between drying parameters ...and state of water under different microwave vacuum drying conditions. Three kinds of materials, carrot (fruit), banana (vegetable) and pleurotus eryngii (edible fungus), were tested in the experiment of applicability. The resulted showed that the information of Atotal and T23 can be used to analyze the drying behavior and the information of A20, A21 and A22 can be used as the fingerprint characteristics of material discrimination. Three classic models (PLS, SVM and BP-ANN) were compared to study the prediction ability of moisture content with the inputs of A20, A21, A22, A23 and Atotal. The performance of BP-ANN model was the best. Although the BP-ANN model of mixed species was not as good as the BP-ANN model of single fruit or vegetable, it still had excellent predictive performances with R2 0.9969 and RMSE 0.0184 to meet the needs of current industry and production.
•A rapid real-time nondestructive detection method of combination of LF-NMR and BP-ANN was set up.•The information of Atotal and T23 can be used to analyze the drying behavior.•The information of A20, A21 and A22 can be used as the fingerprint characteristics of material discrimination.•The BP-ANN model of mixed species had excellent predictive performances with R2 0.9969 and RMSE 0.0184.
Developing high-performance membranes is an extremely significant strategy to combat increasing severe oil pollution. However, most of the previously reported superwettable membranes have been ...inevitably involved with the use of toxic solvents and complicated preparation processes. In addition, most of them lacked the capacity of separating crude oil-in-water emulsions. Herein, a facile and green strategy is employed to fabricate a polytetrafluoroethylene (PTFE) membrane with a mixed suspension of PDA@ZIF-8 and carboxymethyl cellulose (CMC) using water as a solvent via the vacuum filtration method. Combining hydrophilic property with micro–nano-roughness, the CMC-PDA@ZIF-8-coated PTFE membrane (CPZP membrane) exhibits excellent underwater superoleophobicity. More importantly, the separation efficiency of various surfactant-stabilized oil-in-water emulsions including crude oil/water emulsion is higher than 99.2% with a flux up to 1306.5 L m–2 h–1, and the separation performance remains nearly the same after 10 cycles. Moreover, outstanding underwater superoleophobic and self-cleaning properties are maintained after long-distance sandpaper abrasion and multiple bending tests. Meanwhile, its exceptional separation performance is still maintained in harsh environments (3.5 wt % NaCl, 1 M HCl, 60 °C hot water) even after immersing it for 24 h. Therefore, this green-prepared and high-performance membrane has tremendous application prospects in treating oily wastewater.
Evolutes of fronts in the Minkowski plane Li, Yanlin; Sun, Qing‐You
Mathematical methods in the applied sciences,
15 November 2019, Letnik:
42, Številka:
16
Journal Article
Recenzirano
We consider the differential geometry of evolutes of singular curves and give the definitions of spacelike fronts and timelike fronts in the Minkowski plane. We also give the notions of moving frames ...along the non‐lightlike fronts in the Minkowski plane. By using the moving frames, we define the evolutes of non‐lightlike fronts and investigate the geometric properties of these evolutes. We obtain that the evolute of a spacelike front is a timelike front and the evolute of a timelike front is a spacelike front. Since the evolute of a non‐lightlike front is also a non‐lightlike front, we can take evolute again. We study the Minkowski Zigzag number of non‐lightlike fronts and give the n‐th evolute of the non‐lightlike front. Finally, we give an example to illustrate our results.
The lack of stable and efficient techniques to synthesize high‐quality large‐area thin films is one of the major bottlenecks for the real‐world application of the 2D transition metal dichalcogenides. ...In this work, the growth of molybdenum disulfide (MoS2) on sapphire substrates by sulfurizing the MoO3 film deposited by atomic layer deposition (ALD) is reported. The advantages of the ALD method can be well inherited, and the synthesized MoS2 films exhibit excellent layer controllability, wafer‐scale uniformity, and homogeneity. MoS2 films with desired thickness can be obtained by varying MoO3 ALD cycles. The atomic force microscope and Raman measurements demonstrate that the ALD‐based MoS2 has good uniformity. Clear Raman shift as a function of the film thickness is observed. Field‐effect transistor devices are fabricated through a transfer‐free and top‐down process. High On/Off current ratio (≈104) and medium‐level electron mobilities (≈0.76 cm2 V−1 s−1 for monolayer, and 5.9 cm2 V−1 s−1 for four‐layer) are obtained. The work opens up an attractive approach to realize the application of wafer‐scale 2D materials in integrated circuits and systems.
MoS2 films are acquired by the sulfurization of a MoO3 film predeposited by atomic layer deposition (ALD). The synthesized MoS2 retains the inherent benefits from the ALD process, including thickness controllability, reproducibility, and uniformity. Field‐effect transistors are fabricated through a transfer‐free and top‐down process. High On/Off current ratio (≈104) and electron mobility (up to 5.9 cm2 V−1 s−1) are obtained.
The formation of zygote is the beginning of mammalian life, and dynamic epigenetic modifications are essential for mammalian normal development. H3K27 di-methylation (H3K27me2) and H3K27 ...tri-methylation (H3K27me3) are marks of facultative heterochromatin which maintains transcriptional repression established during early development in many eukaryotes. However, the mechanism underlying establishment and regulation of epigenetic asymmetry in the zygote remains obscure. Here we show that maternal EZH2 is required for the establishment of H3K27me3 in mouse zygotes. However, combined immunostaining with ULI-NChIP-seq (ultra-low-input micrococcal nuclease-based native ChIP-seq) shows that EZH1 could partially safeguard the role of EZH2 in the formation of H3K27me2. Meanwhile, we identify that EHMT1 is involved in the establishment of H3K27me2, and that H3K27me2 might be an essential prerequisite for the following de novo H3K27me3 modification on the male pronucleus. In this work, we clarify the establishment and regulatory mechanisms of H3K27me2 and H3K27me3 in mouse zygotes.
Vehicle path planning is a key issue for car navigation systems. When path planning, considering the time spent at intersections is more in line with the actual situation, so it is of practical ...significance to study the path planning problem take account intersection attributes. In this article, we study the problem in a deterministic network, taking the minimization of travel time from the origin to the destination as the optimization goal. For this purpose, we construct a mathematical model for the problem. This paper proposes a reverse labeling Dijkstra algorithm (RLDA) based on traditional Dijkstra algorithm to solve the problem, it is proved that the correctness of the RLDA algorithm theoretically, and analyze that the RLDA algorithm has a lower polynomial time complexity. Finally, we selected the actual road network as the simulation experiment object to verify the effectiveness of the algorithm searching for the optimal path. And select 10 groups of networks of different sizes and conduct extensive experiments to compare the convergence efficiency and calculation speed between RLDA and PSO, GA, ACO, NNA, OPABRL. The statistical results show that the convergence rate of the RLDA algorithm is better than that of ACO, NNA, and GA. When the number of network nodes is less than 350, the algorithm has the smallest running time.
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