Mixed potential gadolinia-doped ceria (GDC)-based gas sensors using a double perovskite composite oxide (Sr2NiMoO6) were fabricated to detect ethanol. The influence of the sensing materials sintered ...at different temperatures on the sensor properties was investigated. The results showed that Sr2NiMoO6 annealed at 1000 °C was the most suitable sensing material for detecting ethanol due to its suitable micromorphology and high electrochemical catalytic activity. The sensor attached with Sr2NiMoO6-1000 °C displayed the highest sensitivity to 1–200 ppm ethanol at 550 °C, the response value ΔV was piecewise linearly with the logarithm of ethanol concentration, and the slopes were −8 and −51.3 mV/decade in the ranges of 1–10 ppm and 10–200 ppm ethanol, respectively. Moreover, the stability and sensing mechanism of the sensor were also investigated.
•Double perovskite type oxide Sr2NiMoO6 was utilized to fabricate Ce0.8Gd0.2O1.95-based mixed potential type gas sensor.•Sr2NiMoO6 sensing material exhibited high response towards ethanol.•The influence of sintering temperature of Sr2NiMoO6 on the sensing performance was mainly discussed.
Based on the analysis of 5G and Internet of Things technology, this paper proposes the reference architecture of smart factory and its application path for traditional manufacturing enterprises in ...China, in which the intelligent manufacturing workshop is the core component of smart factory. The Internet of Things technology combined the advanced technologies (Industrial Big Data, WSN, RFID, Cloud Computing Platform) and provides hardware network foundation and technical theory for designing the real-time tracking and monitoring system of intelligent workshop products. The developed system has the advantages of low cost, rapid deployment, and convenient expansion, which traditional manufacturing enterprises realize intelligent management based on IoT application platform.
The ambient electrocatalytic N2 reduction reaction (NRR) enabled by TiO2 has attracted extensive recent attention. Previous studies suggest the formation of Ti3+ in TiO2 can significantly improve the ...NRR activity, but it still remains unclear what kinds of Ti3+ are effective. Herein, it is demonstrated that mixed‐valent Cu acts as an effective dopant to modulate the oxygen vacancy (VO) concentration and Ti3+ formation, which markedly improves the electrocatalytic NRR performance. In 0.5 m LiClO4, this electrocatalyst attains a high Faradic efficiency of 21.99% and a large NH3 yield of 21.31 µg h−1 mgcat.−1 at –0.55 V vs reversible hydrogen electrode, which even surpasses most reported Ti‐based NRR electrocatalysts. Using density function theory calculations, it is evidenced that mixed‐valent Cu ions modulate the TiO2 (101) surface with multiple oxygen vacancies, which is beneficial for generating different Ti3+ 3d1 defect states localized below the Fermi energy. N2 activation and adsorption are effectively strengthened when Ti3+ 3d1 defect states present the splitting of eg and t2g orbitals, which can be modulated by its coordination structure. The synergistic roles of the three ion pairs formed by the VO defect, including Cu1+–Ti4+, Ti3+–Ti4+ and Ti3+–Ti3+, are together responsible for the enhanced NRR performance.
Cu‐doped TiO2 nanoparticles are highly active toward ambient N2‐to‐NH3 conversion with excellent selectivity. In 0.5 m LiClO4, this catalyst attains a high Faradaic efficiency of 21.99% and a large NH3 yield of 21.31 µg h‒1 mgcat.‒1 at ‒0.55 V versus reversible hydrogen electrode. Density function theory calculations are further discussed for the N2 reduction reaction catalytic mechanism on the Cu‐doped TiO2 (101) surface.
Purpose. Accumulated evidence suggests that reproductive factors are related to different breast cancer subtypes, but most studies on these relationships are mainly focused on middle-aged and older ...patients, and it remains unclear how reproductive factors impact different subtypes of breast cancer in young women. Methods. We assessed the relationships between fertility factors and luminal A, luminal B, human epidermal growth factor receptor 2 (HER2)-enriched, and triple-negative breast cancer (TNBC) subtypes in 3792 patients and 4182 controls aged 20–70 years. Data on the reproductive history of the study participants were acquired through face-to-face interviews and questionnaires. We conducted case-control comparisons among tumor subtypes based on estrogen receptor (ER), progesterone receptor (PR), and HER2 statuses using unconditional polychotomous multivariate logistic regression models to compute odds ratios (ORs) and 95% confidence intervals (CIs). Results. Parity was inversely related to both luminal A and luminal B subtypes in young women and older women (all Ptrend<0.05). Later age at first full-term birth was inversely related to the luminal A subtype (Ptrend<0.05) in young women but correlated with an increased risk of the luminal A subtype (Ptrend<0.05) in older women. Parous Chinese women 40 years old or younger who breastfed for 12 months or longer had a lower risk of luminal B and TNBC subtypes than women who never breastfed (OR=0.55, 95% CI 0.36-0.84 and OR=0.52, 95% CI 0.28-0.99, respectively). Conclusions. Our results implied that parity exerted a strong protective effect against luminal A and luminal B subtype breast cancer in young Chinese women, and long-term breastfeeding obviously decreased the risk of luminal B and TNBC subtypes in this population.
Variational mode decomposition (VMD) is a suitable tool for processing cavitation-induced vibration signals and is greatly affected by two parameters: the decomposed number
K
and penalty factor
α
...under strong noise interference. To solve this issue, this study proposed self-tuning VMD (SVMD) for cavitation diagnostics in fluid machinery, with a special focus on low signal-to-noise ratio conditions. A two-stage progressive refinement of the coarsely located target penalty factor for SVMD was conducted to narrow down the search space for accelerated decomposition. A hybrid optimized sparrow search algorithm (HOSSA) was developed for optimal
α
fine-tuning in a refined space based on fault-type-guided objective functions. Based on the submodes obtained using exclusive penalty factors in each iteration, the cavitation-related characteristic frequencies (CCFs) were extracted for diagnostics. The power spectrum correlation coefficient between the SVMD reconstruction and original signals was employed as a stop criterion to determine whether to stop further decomposition. The proposed SVMD overcomes the blindness of setting the mode number
K
in advance and the drawback of sharing penalty factors for all submodes in fixed-parameter and parameter-optimized VMDs. Comparisons with other existing methods in simulation signal decomposition and in-lab experimental data demonstrated the advantages of the proposed method in accurately extracting CCFs with lower computational cost. SVMD especially enhances the denoising capability of the VMD-based method.
Potassium‐ion batteries (PIBs) are recognized as promising alternatives for lithium‐ion batteries as the next‐generation energy storage systems. However, the larger radius of K+ hinders the K+ ...insertion into the conventional carbon electrode and results in sluggish potassiation kinetics and poor cycling stability. Here, nitrogen and fluorine dual doping of soft carbon nanotubes (NFSC) anode are synthesized in one pot, achieving extraordinary electrochemical performance for PIBs. It is demonstrated that NFSC with a doping dose of 5.6 at% nitrogen and 1.3 at% fluorine together exhibits the highest reversible capacity of 238 mAh g−1 at 0.2 A g−1 and cycling stability of 186 mAh g−1 after 1000 cycles at 1 A g−1. The extraordinary electrochemical performance can be attributed to the hollow structure, expanded interlayer distance, nitrogen and fluorine dual doping, and the binding ability of abundant defect sites. Moreover, density functional theory shows that the extra fluorine modification can dramatically enhance the conventional nitrogen doping effect and reduces the formation energy which makes a great contribution to the improvement of electrical conduction and K‐ions insert. This work may promote the development of low‐cost and sustainable carbon‐based materials for PIBs and other advanced energy storage devices.
The nitrogen and fluorine dual‐doped soft carbon fiber serves as the advanced anode for potassium ion battery. The dual‐doping effect is realized by locking the fluorine and nitrogen sources in the polypyrrole fiber cage which boosts the high conductivity, outstanding rate performance, and cycling stability.
Lightweight, and broad and strong absorption are still a huge challenge for electromagnetic (EM) wave absorbers. Here, we propose a facile oxidative polymerization-carbonization strategy to ...synthesize O, S, N codoped carbon planar helixes for superior EM wave absorbers. The spiral cetyltrimethylammounium bromide crystallites act as a template for the in-situ oxidative polymerization of pyrroles into ordered PPy spiral nanowires. Sintering temperature (Ts) was used to adjust the defects, heteroatoms, graphitization degree, and properties of the carbonized products. With Ts varying from 400 °C to 800 °C, internal stress and heteroatom (N, O, S) content decreased, causing the decreased defect/dipole polarization and increased graphitization degree and conductivity loss. As a result, one broad high-frequency absorption band was exhibited by carbon planar helixes produced at 400 °C− 500 °C, two broad absorption bands were exhibited by those formed at 600 °C, and three absorption bands were exhibited by those formed at 700 °C − 800 °C. The carbon planar helix formed at 700 °C exhibited broader bandwidth (4.96 GHz), thinner sample thickness (1.4 mm), and stronger absorption (−35.44 dB) than those of other absorbers. The superior properties are attributed to a combination of dipole/defect polarization, interface polarization, conductivity loss, multiple scattering, and multiple LC-resonances generated from the unique planar helical structure, defects, heteroatoms, and local electric network.
Display omitted
•A facile oxidative polymerization-carbonization strategy for carbon planar helixes.•Modulation of the defects, heteroatoms, graphitization degree.•Investigating electromagnetic wave absorption capabilities.•Revealing the enhancement mechanism of the microwave absorption.
Cadmium (Cd) contamination in paddy soils and the related pollution risk of rice grain have received increasing attention. Agronomic measures, such as the application of sulfur and changes in water ...regimes, were reported to mitigate the accumulation of Cd in rice. However, there is limited information on the combined effects of sulfur application and water regimes. Therefore, a pot experiment was conducted to investigate the effects of two sulfur forms, three water regimes and multiple sulfur application rates on Cd accumulation in rice. The sulfur was applied as SO42− (SVI, replacing the traditional fertilizers by SO42--containing fertilizers), and element S (S0) was applied at 0, 10, 20, 30 and 40 mg S kg−1 soil. The water regimes were continuous flooding (F), flooding-moist alternation (FM), and moist irrigation (M), for a total of 30 treatments. The results indicated that application of SVI exceeding 30 mg S kg−1 significantly reduced the Cd concentrations in brown rice by 31.1–56.3%, and the Cd concentrations decreased with increasing amount of irrigation water. Similar reductions in Cd concentrations in rice shoots and rice straw collected at tillering and maturity stages were observed after application of SVI. However, the effect of S0 application on Cd accumulation in grain was not significant under different water regimes. Furthermore, this study found that application of both SVI and S0 inhibited the transfer of Cd from rice roots to shoots in most cases. These findings indicate that replacing traditional fertilizers with SO42--containing fertilizers, especially combined with increased irrigation, could be a potential approach to mitigate Cd accumulation in rice growing in Cd-contaminated acidic paddy soils.
Display omitted
•The effect of sulfur supply on the accumulation of Cd in rice under different water regimes was tested.•Reduction effect of SVI on rice grain Cd enhanced as irrigation water increased.•Application of S0 has a limited effect on the accumulation of Cd in rice.•Both forms of sulfur inhibited Cd transfer from roots to shoots in most cases.
Scutellaria–coptis herb couple (SC) is one of the well-known herb couples in many traditional Chinese compound formulas used for the treatment of diabetes mellitus (DM), which has been used to treat ...DM for thousands of years in China.
Few studies have confirmed in detail the anti-diabetic activities of SC in vivo and in vitro. The present investigations aimed to evaluate the anti-diabetic activity of SC in type 2 diabetic KK-Ay mice and in RAW264.7 macrophages to understand its possible mechanism.
High-performance liquid chromatography with ultraviolet detection (HPLC-UV) and LC-LTQ-Orbitrap Pro mass spectrometry were used to analyze the active ingredients of SC extracts and control the quality. A type 2 diabetic KK-Ay mice model was established by high-fat diet. Body weight, fasting blood glucose levels, fasting blood insulin levels, glycosylated hemoglobin and glycosylated serum protein were measured. The effects of SC on total cholesterol (TC), high-density lipoprotein (HDL) and triglyceride (TG) levels were examined. The lipopolysaccharide (LPS), interleukin-6 (IL-6) and tumour necrosis factor alpha (TNF-α) levels were measured. Gut microbial communities were assayed by polymerase chain reaction (PCR) and PCR-denaturing gradient gel electrophoresis (PCR-DGGE) methods. The expressions of Toll-like receptor 4 (TLR4) and MyD88 protein in the colons were measured by western blot. In RAW264.7 macrophages, IL-6, TNF-α, TLR4 and MyD88 protein levels were measured by enzyme-linked immunosorbent assay (ELISA) kits or western blot, and the mRNA expression of IL-6, TNF-α and TLR4 was examined by the real time PCR.
The present results showed that the SC significantly increased blood HDL and significantly reduced fasting blood glucose, fasting blood insulin, glycosylated hemoglobin, glycosylated serum protein, TC, TG, LPS, IL-6 and TNF-α levels (P < 0.05 or P < 0.01) in type-2 diabetic KK-Ay mice. Furthermore, SC could regulate the structure of intestinal flora. Additionally, the expressions of TLR4 and MyD88 protein in the colons were significantly decreased in the model group (P < 0.05 or P < 0.01). However, SC had no significant effect on weight gain. In RAW264.7 macrophages, SC containing serum (SC-CS) (5%, 10% and 20%) significantly decreased IL-6, TNF-α, TLR4 and MyD88 protein levels and the mRNA expression of IL-6, TNF-α and TLR4 (P < 0.05 or P < 0.01).
The anti-diabetic effects of SC were attributed to its regulation of intestinal flora and anti-inflammation involving the TLR4 signaling pathway. These findings provide a new insight into the anti-diabetic application for SC in clinical settings and display the potential of SC in the treatment of DM.
Display omitted
PDF
