The novel fault diagnosis method of gearbox based on Fourier Bessel series expansion-based empirical wavelet transform (FBEWT) and manifold regularization extreme learning machine (MRELM) is proposed ...to obtain excellent fault diagnosis results of gearbox in this paper. A new feature extraction strategy based on Fourier Bessel series expansion-based empirical wavelet transform is used to capture the key non-stationary features of the vibrational signal of gearbox, and significantly improve the diagnosis ability of gearbox. The ELM with manifold regularization is proposed for fault diagnosis of gearbox. In order to outstand the superiority and stability of the proposed FBEWT and manifold regularization ELM, the balanced dataset and unbalanced dataset, respectively, are used. The experimental results testify that FBEWT-MRELM are more superior and stable than FBEWT-ELM, EWT-MRELM, and EWT-ELM regardless of balanced dataset and unbalanced dataset.
The process of energy conservation and emission reduction in China requires the specific and accurate evaluation of the energy efficiency of the industry sector because this sector accounts for 70 ...percent of China's total energy consumption. Previous studies have used a “black box” DEA (data envelopment analysis) model to obtain the energy efficiency without considering the inner structure of the industry sector. However, differences in the properties of energy utilization (final consumption or intermediate conversion) in different industry departments may lead to bias in energy efficiency measures under such “black box” evaluation structures. Using the network DEA model and efficiency decomposition technique, this study proposes an adjusted energy efficiency evaluation model that can characterize the inner structure and associated energy utilization properties of the industry sector so as to avoid evaluation bias. By separating the energy-producing department and energy-consuming department, this adjusted evaluation model was then applied to evaluate the energy efficiency of China's provincial industry sector.
•An adjusted network DEA (data envelopment analysis) model for energy efficiency evaluation is proposed.•The inner structure of industry sector is taken into account for energy efficiency evaluation.•Energy final consumption and energy intermediate conversion processes are separately modeled.•China's provincial industry energy efficiency is measured through the adjusted model.
The semi-heterogeneous g-C3N4/NaI dual catalytic system-driven C–C bond formation between quinoxalin-2(1H)-ones and arylhydrazines under blue light irradiation has been reported for the first time. ...The photo-generated hole acted as a traceless oxidant to turn over the iodide salt redox catalyst cycle and the photo-generated electron served as a clean reductant to promote the bond formation process. A wide range of 3-arylquinoxaline-2 (1H)-ones were obtained in high yields with excellent functional group tolerance.
LiNi0.8Co0.1Mn0.1O2 is considered as a promising cathode material for lithium ion batteries because of its high capacity and low cost. However, the LiNi0.8Co0.1Mn0.1O2 suffers structural instability ...and irreversible phase transition during charge/discharge processes, especially under high voltage, resulting in serious capacity fading and thermal runaway. Here, we propose a simple and effective method of modifying LiNi0.8Co0.1Mn0.1O2 by Mg doping. Benefiting from the pillaring effects of inactive Mg in the crystal structure, Li(Ni0.8Co0.1Mn0.1)1-xMgxO2 materials exhibit low Li+/Ni2+ cation mixing, high structural stability, and improved cyclic stability in the voltage of 3.0–4.5 V. The optimal Li(Ni0.8Co0.1Mn0.1)0.97Mg0.03O2 achieves a high capacity retention of 81% over 350 cycles at 0.5 C and exhibits enhanced thermal stability at 4.5 V. The promotion mechanism is explored systematically by a combination study of electrochemical characterizations, demonstrating the faster Li+ diffusion kinetics, higher electronic conductivity, and stronger structure due to the Mg doping. Moreover, the full cell of Li(Ni0.8Co0.1Mn0.1)0.97Mg0.03O2//mesocarbon microbeads delivers a promising energy density of 595.3 W h kg−1 at 0.5 C (based on the mass of the cathode). The present work demonstrates that moderate Mg doping is a facile yet effective strategy to modify high-performance LiNi0.8Co0.1Mn0.1O2 for high-voltage lithium ion batteries.
•LiNi0.8Co0.1Mn0.1O2 cathode material is modified by Mg doping.•The Li+/Ni2+ mixing of LiNi0.8Co0.1Mn0.1O2 material is reduced by Mg doping.•NCMMg0.03 material exhibits improved cycling retention and thermal stability.•The NCMMg0.03//MCMB full cell delivers an energy density of 595.3 W h kg−1 at 0.5 C.
Bisphenol A (BPA) is a well-known endocrine disruptor that has elicited great concern because of its potential toxic effects in organisms. In this study, the effects of BPA and several BPA structural ...analogs, including BPB, BPS, BPF, and BPAF, on the reproductive neuroendocrine system were evaluated during zebrafish embryonic and larval development. Our results showed that the numbers of gonadotropin-releasing hormone 3 neurons in zebrafish embryos increased after 100 μg/L BPA analog treatment, and exposure to BPA or its analogs at 1 or 100 μg/L increased the expression of reproductive neuroendocrine-related genes and the levels of typical hormones such as LH, FSH, E2, and GH. Moreover, the effects were associated with increases in the activities of erα, erβ, and cyp19a genes. The respective estrogen receptors (ER) and aromatase (AROM) antagonists significantly attenuated the stimulation of lhβ, fshβ, LH, and FSH expression, thereby proving that BPA analogs affect the reproductive neuroendocrine system via ERs and AROM pathway. Furthermore, we observed that the reproductive neuroendocrine toxicity of BPAF was more similar to that of BPA. This was the first study to comparatively explore the reproductive neuroendocrine toxicities of bisphenols in aquatic organism.
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•The comparative toxicities of BPA, BPB, BPS, BPF, and BPAF on zebrafish embryos were studied.•BPA and its analogs disturb the reproductive neuroendocrine system of zebrafish embryos.•BPAF induced more reproductive neuroendocrine indexes than BPB, BPS, and BPF.•BPA analogs affect the reproductive neuroendocrine system via ER and AROM pathways.
2,4-Bis(trifluoromethyl)phenylboronic acid is a highly effective catalyst for dehydrative amidation between carboxylic acids and amines. Mechanistic studies suggest that a 2 : 2 mixed anhydride is ...expected to be the only active species, and the ortho-substituent of boronic acid plays a key role in preventing the coordination of amines to the boron atom of the active species, thus accelerating the amidation. This catalyst works for α-dipeptide synthesis.
A new multi-stimuli-responsive homopolymer of polyN-2-(diethylamino)ethylacrylamide (PDEAEAM), which combines the thermoresponsive and pH/CO2-responsive moieties of the diethylamino and acrylamide ...groups, was proposed and synthesized by RAFT polymerization. Well-defined PDEAEAM was synthesized by solution RAFT polymerization as indicated by the linear increase in the polymer molecular weight with the monomer conversion and the narrow molecular weight distribution. The appending diethylamino group in the polymer backbone was found to be crucial to determine the thermoresponse of PDEAEAM in water. The parameters including the polymerization degree, the polymer concentration, the deuterated solvent, the terminal attached on the polymer backbone, the additives of salt and urea, and pH and bubbling CO2 affecting the thermoresponse of PDEAEAM in aqueous solution at the lower critical solution temperature (LCST) were investigated. The temperature-variable 1H NMR analysis suggests that the dehydration of PDEAEAM at temperature above LCST is ascribed to the weakened hydrogen bonding between the CONHCH2 and/or (CH2N(CH2CH3)2) moieties with the solvent of water. The proposed multi-stimuli-responsive homopolymer of PDEAEAM has two advantages of (1) the convenient and controllable RAFT synthesis and (2) the pH/CO2 tunable LCST at ∼36 °C being very close to body temperature.
Aqueous rechargeable zinc‐based batteries have sparked a lot of enthusiasm in the energy storage field recently due to their inherent safety, low cost, and environmental friendliness. Although ...remarkable progress has been made in the exploration of performance so far, there are still many challenges such as low working voltage and dissolution of electrode materials at the material and system level. Herein, the central tenet is to establish a systematic summary for the construction and mechanism of different aqueous zinc‐based batteries. Details for three major zinc‐based battery systems, including alkaline rechargeable Zn‐based batteries (ARZBs), aqueous Zn ion batteries (AZIBs), and dual‐ion hybrid Zn batteries (DHZBs) are given. First, the electrode materials and energy storage mechanism of the three types of zinc‐based batteries are discussed to provide universal guidance for these batteries. Then, the electrode behavior of zinc anodes and strategies to deal with problems such as dendrite and passivation are recommended. Finally, some challenge‐oriented solutions are provided to facilitate the next development of zinc‐based batteries. Combining the characteristics of zinc‐based batteries with good use of concepts and ideas from other disciplines will surely pave the way for its commercialization.
Herein, a systematic summary for the construction and mechanism of different aqueous zinc‐based batteries is established. Details for three major zinc‐based battery systems, including alkaline rechargeable Zn‐based batteries, aqueous Zn ion batteries, and dual‐ion hybrid Zn batteries are given. Combining the characteristics of zinc‐based batteries with good use of concepts and ideas from other disciplines will surely pave the way for its commercialization.
Although mass customization, which utilizes modularization to simultaneously increase product variety and maintain mass production (MP) efficiency, has become a trend in recent times, there are some ...limitations to mass customization. Firstly, customers do not participate wholeheartedly in the design phase. Secondly, potential combinations are predetermined by designers. Thirdly, the concept of mass customization is not necessary to satisfy individual requirements and is not capable of providing personalized services and goods. Industry 4.0 is a collective term for technologies and concepts of value chain organization. Based on the technological concepts of radio frequency identification, cyber-physical system, the Internet of things, Internet of service, and data mining, Industry 4.0 will enable novel forms of personalization. Direct customer input to design will enable companies to increasingly produce customized products with shorter cycle-times and lower costs than those associated with standardization and MP. The producer and the customer will share in the new value created. To overcome the gaps between mass customization and mass personalization, this paper presents a framework for mass personalization production based on the concepts of Industry 4.0. Several industrial practices and a lab demonstration show how we can realize mass personalization.
Numerous dams disrupt freshwater animals. The uppermost population of the critically endangered Yangtze finless porpoise has been newly formed below the Gezhouba Dam, however, information regarding ...the local porpoise is scarce. Passive acoustic monitoring was used to detect the behaviors of porpoises below the Gezhouba Dam. The influence of shipping, pandemic lockdown, hydrological regime, and light intensity on the biosonar activity of dolphins was also examined using Generalized linear models. Over the course of 4 years (2019–2022), approximately 848, 596, and 676 effective monitoring days were investigated at the three sites, from upstream to downstream. Observations revealed significant spatio‐temporal biosonar activity. Proportion of days that are porpoise positive were 73%, 54%, and 61%, while porpoise buzz signals accounted for 78.49%, 62.35%, and 81.30% of all porpoise biosonar at the three stations. The biosonar activity of porpoises was much higher at the confluence area, particularly at the MZ site, during the absence of boat traffic, and during the Pandemic shutdown. Temporal trends of monthly, seasonal, and yearly variation were also visible, with the highest number of porpoises biosonar detected in the summer season and in 2020. Significant correlations also exist between the hydrological regime and light intensity and porpoise activity, with much higher detections during nighttime and full moon periods. Hydropower cascade development, establishment of a natural reserve, fish release initiatives, and implementation of fishing restrictions may facilitate the proliferation of the porpoise population downstream of the Gezhouba Dam within the Yichang section of the Yangtze River. Prioritizing restoration designs that match natural flow regimes, optimize boat traffic, and reduce noise pollution is crucial for promoting the conservation of the local porpoises.
Passive acoustic monitoring was used to detect the behaviors of porpoises below the Gezhouba Dam. The influence of shipping, pandemic lockdown, hydrological regime, and light intensity on the biosonar activity of dolphins was also examined using Generalized linear models.