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Feasibility of offshore wind turbines for linkage with onshore green hydrogen demands: A comparative economic analysis
No full textImprudent fossil fuel use for getting energy caused serious environmental problems making us necessary to seeking for alternative energy sources which are renewable and sustainable. Using wind energy is currently considered as one of feasible renewable energy sources, however, the problem of noise pollution from the sweep of turbine blades should be solved. As a feasible solution for the noise pollution problem, the construction of wind farms offshore is currently considered. In addition, many factors can change the onshore wind speed, while offshore wind has a higher wind speed and consistency, which leads to higher energy efficiency. However, the remained intermittency of wind energy makes storage media such as H-2 necessary, thus, the construction of an offshore wind base H-2 production system can be required for protecting the energy security. In this study, a comparative economic analysis is conducted to verify feasible equipment placements of offshore wind-based H-2 production systems in various possible cases with different electrolyzer types, wind speeds, and offshore distances. An optimization study for 4 case scenarios with different regions, offshore lengths, and kinds of electrolyzers, was preliminarily conducted to find several placements that are economically optimal in common. For the optimization, a mixed-integer programming tool in Python was used, and as a result, three absolutely economical placements were selected. Then, the comparative economic analysis with considering the selected three cases was conducted indicating the most feasible placement according to the considered offshore length and wind speed, and costs ranged from 1.64 to 4.46 $ kgH(2)(-1). From the optimal cases for considered regions (Ulsan, Magallanes), the system using alkaline electrolyzer can achieve the feasible prices for both regions, while using other types stay in ranges of the current green H-2 produced by electrolysis
Rheological and topological properties of entangled short-chain branched polymers in comparison to the linear analogs under shear flow
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Boosting square tensile strain to promote 4-variants in-plane ferroelectricity and switchable ternary polar states
No full textLow-Voltage Stretchable Electroluminescent Loudspeakers with Synchronous Sound and Light Generation
No full textStretchable sound-in-displays, which can generate synchronous sound and light directly from the display without a separate speaker, allow immersive audio and visual perception even on curved surfaces. In stretchable sound-in-displays, alternating current electroluminescent (ACEL) devices have been used as light-emitting sources owing to their high brightness and stability. However, stretchable ACEL devices that use low dielectric constant (lc) materials require a high operating voltage for generating light and sound. Herein, we demonstrate a stretchable ACEL loudspeaker with a low operating voltage using stretchable high -lc dielectrics and strain-insensitive electrodes. Our device exhibits 87.7 cd/m2 of luminance and 79.70 dB of sound pressure level at an operating voltage of 120 V and 10 kHz. As the next platform of wearable devices, the suggested ACEL loudspeaker exhibits high-quality synchronous light and sound generation performance even under various types of mechanical deformation, such as finger flexion and wrist bending
Human coronavirus 3CL proteases cleave septins and disrupt Hedgehog signaling, causing ciliary dysfunction
No full textCoronaviruses target ciliate cells causing the loss of cilia, acute rhinorrheas, and other ciliopathies. The loss of ciliary function may help the virus infect, replicate, and spread. However, the molecular mechanisms by which coronaviruses cause ciliary defects are still unclear. Herein we demonstrate how coronavirus infection and severe acute respiratory syndrome coronavirus2 3CL protease induce cilia dysfunction by targeting a host protein septin that is required for the structure and function of cilia. Further, we demonstrate that coronaviruses and 3CL protease lead to the cleavage of several septin proteins (SEPT2, -6, and -9), producing cleaved obstructive fragments. Furthermore, ectopic expression of cleaved SEPT2 fragments shows defective ciliogenesis, disoriented septin filaments, and ablated Sonic Hedgehog (SHH) signaling in a protease activity-dependent manner. We present that the 3CLpro inhibitors are potent and prevent abnormal ciliary structures and SHH signaling. These results provide useful insights into the general mechanisms underlying ciliary defects caused by coronaviruses, which, in turn, facilitate virus spread and prove that preclinical and clinical 3CL protease inhibitors may prove useful as therapeutics for treating ciliary defects of coronaviruses
Boosting Charge Transfer Efficiency by Nanofragment MXene for Efficient Photoelectrochemical Water Splitting of NiFe(OH)X Co- Catalyzed Hematite
No full textThe use of oxygen evolution co-catalysts (OECs) with hematite photoanodes has received much attention because of the potential to reduce surface charge recombination. However, the low surface charge transfer and bulk charge separation rate of hematite are not improved by decorating with OECs, and the intrinsic drawbacks of hematite still limit efficient photoelectrochemical (PEC) water splitting. Here, we successfully overcame the sluggish oxygen evolution reaction performance of hematite for water splitting by inserting zero-dimensional (0D) nanofragmented MXene (NFMX) as a hole transport material between the hematite and the OEC. The 0D NFMX was fabricated from two-dimensional (2D) MXene sheets and deposited onto the surface of a three-dimensional (3D) hematite photoanode via a centrifuge-assisted method without altering the inherent performance of the 2D MXene sheets. Among many OECs, NiFe(OH)x was selected as the OEC to improve hematite PEC performance in our system because of its efficient charge transport behavior and high stability. Because of the great synergy between NFMX and NiFe(OH)x, NiFe(OH)x/NFMX/Fe2O3 achieved a maximum photocurrent density of 3.09 mA cm-2 at 1.23 VRHE, which is 2.78-fold higher than that of alpha-Fe2O3 (1.11 mA cm-2). Furthermore, the poor stability of MXene in an aqueous solution for water splitting was resolved by uniformly coating it with NiFe(OH)x, after which it showed outstanding stability for 60 h at 1.23 VRHE. This study demonstrates the successful use of NFMX as a hole transport material combined with an OEC for highly efficient water splitting
A non-destructive correlated energy spread monitor using multi-stripline electrodes for X-ray free electron lasers
No full textDuring X-ray free electron laser (XFEL) operation, electron beam parameters such as the correlated energy spread, which affects the self-amplified spontaneous emission (SASE) spectrum, should remain optimized for the best performance. However, the correlated energy spread often varies from the optimized condition owing to the drift of RF stations, even when a feedback system with low-level radio frequency is operating. Non-destructive correlated energy spread monitoring could offer a means to stabilize such variations and improve the performance of X-ray generation by maintaining the spectral quality. Herein, we investigated the feasibility of a non-destructive correlated energy spread monitor based on multi-stripline electrodes for use with the 200 pC electron beam at the Pohang Accelerator Laboratory XFEL (PAL-XFEL). Beam tracking and electromagnetic simulations indicated that the correlated energy spread up to approximately 0.1% could be measured without intercepting the beam at the bunch compressors of the PAL-XFEL. Through the 3D FEL simulation, we confirmed that keeping the SASE energy spectrum bandwidth to 0.05-0.15%, with a photon energy of 9.7 keV at the undulator, requires the correlated energy spread of the electron beam to be within 0.12-0.35% at the third bunch compressor. From the simulations, we conclude that the non-destructive correlated energy spread monitor based on multi-stripline electrodes is applicable to XFEL facilities and could serve as an effective optimization tool
Electric-field-driven interfacial trapping of drifting triboelectric charges via contact electrification
No full textIn this paper, we report a new facile strategy to maximize the charge density for a high-output triboelectric nanogenerator (TENG). It was realized by designing a new cationic material structure consisting of SiO2 and MoS2 coated on a Ni-mesh in sequence. Compared with Ni-mesh-based TENGs, this new TENG generated about 13 times higher output power and a superior charge density of over 1000 mu C m(-2) with a slow charge decay rate. Its extremely high charge density could be explained by a low work function of MoS2, an upward bending of the energy band at the interface between MoS2 and SiO2, and a high charge capacity of SiO2. Based on the gear-cam mode, the average output power of the TENG was measured to be about 14.75 W m(-2)
Deep Learning-Based Algorithm for Electromagnetic Interference Noise Removal in Photoacoustic Endoscopic Image Processing
No full textIn this study, we developed deep-learning-based image processing algorithms to remove the electromagnetic interference (EMI) noise included in optical-resolution (OR) photoacoustic endoscopy (PAE) images, and we have witnessed that thereby EMI noise can be significantly removed from those images. Although we do not emphasize this point, engineering problems related to EMI noise form an important and fundamental subject area in electronics since EMI noise frequently intervenes between a sensor and an amplifier. To the best of our knowledge, this paper is the first to deal with the question of removing EMI noise from PAT images by using deep learning techniques