Methyl Orange-Doped Polypyrrole Promoting Growth of ZIF-8 on Cellulose Fiber with Tunable Tribopolarity for Triboelectric Nanogenerator

Cellulose fiber (CelF) is a biodegradable and renewable material with excellent performance but negligible triboelectric polarizability. Methods to enhance and rationally tune the triboelectric properties of CelF are needed to further its application for energy harvesting. In this work, methyl-orange-doped polypyrrole (MO-PPy) was in situ coated on CelF as a mediating layer to promote the growth of metal–organic framework ZIF-8 and to construct a cellulose-based triboelectric nanogenerator (TENG). The results showed that a small amount of MO-PPy generated in situ significantly promoted the growth of ZIF-8 on CelF, and the ZIF-8 deposition ratio was able to increase from 7.8% (ZIF-8/CelF) to 31.8% (ZIF-8/MO-PPy@CelF). ZIF-8/MO-PPy@CelF remained electrically conductive and became triboelectrically positive, and the triboelectricity’s positivity was improved with the increase in the ZIF-8 deposition ratio. The cellulose-based TENG constructed with ZIF-8/MO-PPy@CelF (31.8% ZIF-8 deposition ratio) and polytetrafluoroethylene (PTFE) could generate a transfer charge of 47.4 nC, open-circuit voltage of 129 V and short-circuit current of 6.8 μA—about 4 times higher than those of ZIF-8/CelF (7.8% ZIF-8 deposition ratio)—and had excellent cycling stability (open-circuit voltage remained almost constant after 10,000 cycles). MO-PPy not only greatly facilitated the growth of ZIF-8 on CelF, but also acted as an electrode active phase for TENG. The novel TENG based on ZIF-8/MO-PPy@CelF composite has cheerful prospects in many applications, such as self-powered supercapacitors, sensors and monitors, smart pianos, ping-pong tables, floor mats, etc.

Optimization of Electrical Performance of Defected n+-p-p+ Solar Cell with CdS/BaSi2/Cu2O Heterostructure Using SCAPs 1D

Present study investigates the performance of BaSi2 based BSF structure solar cell. SCAPS 1D simulator has been employed to investigate the heterostructure solar cell. To decrease the recombination loss due to minority carrier, a new configuration is proposed by inclusion of the p-type cuprous oxide (Cu2O) as BSF layer. The Cu2O BSF layer width varying in range 0.1 to 0.4 µm to analyze the feasibility of device for optimum performance. The anticipated structure consists of ZnO/CdS/BaSi2/Cu2O layers and offers the maximum efficiency of above 24%. Parameters for example open circuit voltage (Voc), short-circuit current density (Jsc), fill factor (FF), conversion efficiency (η) and quantum efficiency (QE) of the device have been analyzed graphically. The optimized structure may have significant impact on future development of advanced photovoltaic devices.

Membraneless Photocatalytic Fuel Cell with Double Photoelectrodes for Simultaneous Electricity Generation and Pollutant Degradation

Environmental pollution and new energy development have become topics of increasing concern. Herein, a visible-light-driven photocatalytic fuel cell (PFC) with double photoelectrodes was constructed for simultaneous electricity generation and pollutant degradation, in which graphitic carbon nitride (g-C3N4) generated on W/WO3 nanorod arrays (W/WNR/g-C3N4) was used as the photoanode and Fe3+-doped CuBi2O4 thin film on indium tin oxide (ITO) conductive glass (ITO/CBFeO) was used as the photocathode. The experimental results showed that the WO3/g-C3N4 Z-scheme structure and one-dimensional WNR rod-like structure could effectively suppress the recombination of photogenerated charge carriers and enable W/WNR/g-C3N4 to present a good photocurrent response under visible light irradiation. The Fermi level mismatch between the W/WNR/g-C3N4 photoanode and ITO/CBFeO photocathode could improve the transfer of photogenerated electrons from the photoanode to the photocathode across the external circuit, enabling the constructed PFC to afford high electricity output and good efficiency for pollutant degradation. The short-circuit current density and maximum power density could reach 620 μA cm−2 and 110 μW cm−2, respectively, while the degradation ratio of oxytetracycline reached 97.6% in 90 min. Therefore, the proposed PFC system provides a new way to generate electric energy and degrade pollutants simultaneously.

Receptor-mediated activation of CFTR via prostaglandin signaling pathways in the airway

Cystic fibrosis (CF) is a genetic disease caused by mutations of the gene encoding a cAMP-activated Cl- channel, the cystic fibrosis transmembrane conductance regulator (CFTR). CFTR modulator therapies consist of small-molecule drugs that rescue mutant CFTR. Regimens of single or combinations of CFTR modulators still rely on endogenous levels of cAMP to regulate CFTR activity. We investigated CFTR activation by the natural mediator prostaglandin E2 (PGE2) and lubiprostone and tested the hypothesis that receptor-mediated CFTR activators can be used in combination with currently available CFTR modulators to increase function of mutant CFTR. Primary cultured airway epithelia were assayed in Ussing chambers. Experimental CFTR activators and established CFTR modulators were applied for 24 h and/or acutely and analyzed for their effect on CFTR activity as measured by changes in short-circuit current (ISC). In non-CF airway epithelia, acute application of lubiprostone and PGE2 activated CFTR to levels comparable to forskolin. Pre-treatment (24 h) with antagonists to prostaglandin receptors EP2 and EP4 abolished the ability of lubiprostone to acutely activate CFTR. In F508del homozygous airway epithelia pre-treated with the triple combination of elexacaftor, tezacaftor, and ivacaftor (ELEXA/TEZ/IVA; i.e., Trikafta), acute application of lubiprostone was able to maximally activate CFTR. Prolonged (24 h) co-treatment of F508del homozygous epithelia with ELEXA/TEZ/IVA and lubiprostone increased acute CFTR activation by ~60% compared to treatment with ELEXA/TEZ/IVA alone. This work establishes the feasibility of targeting prostaglandin receptors to activate CFTR on the airway epithelia and demonstrates that co-treatment with lubiprostone can further restore modulator-rescued CFTR.

Improved crystallinity of GaP-based dilute nitride alloys by proton/electron irradiation and rapid thermal annealing

This study presents the positive effects of proton/electron irradiation on the crystallinity of GaP-based dilute nitride alloys. It is found that proton/electron irradiation followed by rapid thermal annealing enhances the PL peak intensity of GaPN alloys, whereas major photovoltaic III-V materials such as GaAs and InGaP degrade their crystal quality by irradiation damage. Atomic force microscopy and transmission electron microscopy reveal no degradation of structural defects. GaAsPN solar cell test devices are then fabricated. Results show that the conversion efficiency increases by proton/electron irradiation, which is mainly caused by an increase in the short-circuit current.

Research on grounding grid corrosion detection based on hybrid artificial intelligence algorithm

As an important part of substation, grounding grid is the main approach to release short-circuit current. Grounding grid is in the complex electromagnetic compund,and with increasely being operated, it is easily corroded for various reasons, resulting in short-circuit current not being discharged normally. It is difficult to detect the grounding grid without excavation, because it is generally buried underground. Therefore, it is very important to accurately detect the grounding grid without excavation. In this paper, a grounding grid detection method based on artificial intelligence hybrid algorithm is proposed. In order to verify the accuracy of the detection method, the grounding grid model is established by using electromagnetic transient simulation software ATP-EMTP. According to the ATP-EMTP simulation model, the node potential of each point of the grounding grid is detected as the reference object for verification. In order to remove the randomness of the simulation results, the average value of 20 tests was used as the corrosion diagnosis result. The results show that the missed diagnosis rate of the proposed in paper was 2.1%, which was reduced by 12.1%, 7.1% and 7.5% respectively compared with the other three algorithms. At the same time, the misdiagnosis is 2.1%, which is reduced by 10%, 6.2% and 12.9% respectively for the other three algorithms. In sum, the corrosion leakage diagnosis rate and misdiagnosis rate of the proposed artificial intelligence algorithm are lower than those of the other three optimization algorithms, and have higher accuracy and stability in corrosion diagnosis.

The.main types of wind turbines-generators in the power supply system

THE PURPOSE. This paper considers the problem of relay protection functioning when the current transformer reaches the saturation mode which is provided by transient processes.METHODS. MATLAB Simulink software environment allows reproducing the method of statespace representation by using structural blocks. The model is verified by comparison the time to saturation, obtained by calculation and according to the graphical data of the model. The separation of variables method extracts and graphically displays the investigated components.RESULTS. This paper reveals that applying the requirements of IEC 61869-2:2012 standard, which determines the worst combination of series of unfavorable factors for current transformers in transient mode, can influence a serious impact on the correct operation of relay protection based on current, reactance or differential principle of action. Saturation of the current transformer can lead to both negative results: false operation of relay protection devices and their failure.CONCLUSION. According to the results of the study, it was determined that the presence of a DC component in the primary short-circuit current has the greatest effect on the protection operation. The delays in the restoration of the RMS value of the short-circuit current reached up to 0.3 seconds, which is comparable with the response time of the second protection zones for microprocessor-based relay protection devices. The DC component of the primary current and the presence of residual magnetic induction of the current transformer provides the largest content of the magnetization current, the largest angular error and also the largest content of the second harmonic component in the secondary short-circuit current.

Optimization of the Sb2S3 Shell Thickness in ZnO Nanowire-Based Extremely Thin Absorber Solar Cells

Extremely thin absorber (ETA) solar cells made of ZnO/TiO2/Sb2S3 core–shell nanowire heterostructures, using P3HT as the hole-transporting material (HTM), are of high interest to surpass solar cell efficiencies of their planar counterpart at lower material cost. However, no dimensional optimization has been addressed in detail, as it raises material and technological critical issues. In this study, the thickness of the Sb2S3 shell grown by chemical spray pyrolysis is tuned from a couple of nanometers to several tens of nanometers, while switching from a partially to a fully crystallized shell. The Sb2S3 shell is highly pure, and the unwanted Sb2O3 phase was not formed. The low end of the thickness is limited by challenges in the crystallization of the Sb2S3 shell, as it is amorphous at nanoscale dimensions, resulting in the low optical absorption of visible photons. In contrast, the high end of the thickness is limited by the increased density of defects in the bulk of the Sb2S3 shell, degrading charge carrier dynamics, and by the incomplete immersion of the P3HT in the structure, resulting in the poor hole collection. The best ETA solar cell with a short-circuit current density of 12.1 mA/cm2, an open-circuit voltage of 502 mV, and a photovoltaic conversion efficiency of 2.83% is obtained for an intermediate thickness of the Sb2S3 shell. These findings highlight that the incorporation of both the absorber shell and HTM in the core–shell heterostructures relies on the spacing between individual nanowires. They further elaborate the intricate nature of the dimensional optimization of an ETA cell, as it requires a fine-balanced holistic approach to correlate all the dimensions of all the components in the heterostructures.