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We report here a selective C6‐nitration of benzothiazolones in the presence of iron nitrate as nitro source. A series of novel 6‐nitrobenzothiazolin‐2‐one derivatives were prepared with moderate to excellent yields at room temperature. The method shows good regioselectivity, broad substrate scope and excellent compatibility with functional groups. Further transformations were performed for the reduction of nitro groups, amination of carbonyl groups and alkylation of amine at the 3‐position in the product. [ABSTRACT FROM AUTHOR]

The development of non-enzymatic glucose detection method is of great significance in the clinical, biological and food sample analysis. In this work, a NiCo.sub.2O.sub.4-Nafion modified glassy carbon electrode was successfully fabricated which can rapidly detect glucose (, Author(s): Suqin Liu [sup.1], Li Liu [sup.1], Wanqiang Wang [sup.1], Yang Zhou [sup.2], Gaopeng Dai [sup.1], Yuanyuan Liu [sup.2] Author Affiliations: (1) grid.412979.0, 0000 0004 1759 225X, School of Food [...]

As a key component of motion support, the rolling bearing is currently a popular research topic for accurate diagnosis of bearing faults and prediction of remaining bearing life. However, most existing methods still have difficulties in learning representative features from the raw data. In this paper, the Xi'an Jiaotong University (XJTU-SY) rolling bearing dataset is taken as the research object, and a deep learning technique is applied to carry out the bearing fault diagnosis research. The root mean square (RMS), kurtosis, and sum of frequency energy per unit acquisition period of the short-time Fourier transform are used as health factor indicators to divide the whole life cycle of bearings into two phases: the health phase and the fault phase. This division not only expands the bearing dataset but also improves the fault diagnosis efficiency. The Deep Convolutional Neural Networks with Wide First-layer Kernels (WDCNN) network model is improved by introducing multi-scale large convolutional kernels and Gate Recurrent Unit (GRU) networks. The bearing signals with classified health states are trained and tested, and the training and testing process is visualized, then finally the experimental validation is performed for four failure locations in the dataset. The experimental results show that the proposed network model has excellent fault diagnosis and noise immunity, and can achieve the diagnosis of bearing faults under complex working conditions, with greater diagnostic accuracy and efficiency. [ABSTRACT FROM AUTHOR]

Nitrous oxide (N2O) is an environmental pollutant that has a significant greenhouse effect and contributes to the depletion of the ozone layer. To address the issues caused by N2O, direct catalytic decomposition of N2O to N2 and O2 has been demonstrated as one of the most efficient methods for its removal. Various metals, particularly noble metals, including Rh, Ru, Pd, Pt, Au, and Ir, have been widely used and investigated as catalysts to facilitate this transformation. Therefore, this review aims to provide an overview of the advances in noble metal-based catalysts studied in recent years. The comprehensive discussion includes the influence of multiple factors, such as catalyst supports, preparation methods, additives, and impurity gases (such as O2, H2O, SO2, NO, and CO2) on the performance of versatile catalysts. Furthermore, this review offers insights into the future trends of catalyst systems for the direct catalytic decomposition of N2O. [ABSTRACT FROM AUTHOR]

The development of non-enzymatic glucose detection method is of great significance in the clinical, biological and food sample analysis. In this work, a NiCo2O4-Nafion modified glassy carbon electrode was successfully fabricated which can rapidly detect glucose (<5 s) with high selectivity. Flower-like nanorod-shaped NiCo2O4 spheres were simply synthesized via an one-pot hydrothermal reaction which were characterized by scanning electron microscope and X-ray diffraction. The as-prepared NiCo2O4 and Nafion modified glassy carbon electrode showed remarkable electrochemical activity for glucose detection in both cyclic voltammetry and chronoamperometry measurements. The anodic current was linearly proportional to glucose concentration in a broad range from 0.1 to 1360 μM. The detection limit of our NiCo2O4−Nafion modified electrode was determined as 10 nM (S/N = 3). Finally, the modified electrode exhibited high stability, selectivity and reproducibility. The electrode has been successfully applied to detect glucose in real food samples. [ABSTRACT FROM AUTHOR]

In this work, (1−x)(0.98Bi0.5Na0.5TiO3‐0.02BiAlO3)‐x(Na0.5K0.5)NbO3 (BNT‐BA‐xKNN) lead‐free pyroelectric ceramics were prepared by a solid‐state reaction method. The effect of Na0.5K0.5NbO3 (KNN) content on microstructure, phase transition, and electrical properties of the BNT‐BA‐xKNN ceramics were systematically investigated. The results show that the appropriate content of KNN can induce the formation of the tetragonal structure, which results in the decreased ferroelectric‐antiferroelectric phase transition temperature as a result of the break of long‐range translational symmetry of BNT lattices. Therefore, the ferroelectric and pyroelectric properties of the BNT‐BA‐xKNN near room temperature are improved. The room‐temperature pyroelectric coefficient significantly increases from 3.66 × 10−4 C/m2/K at x = 0 to 8.04 × 10−4 C/m2/K at x = 0.02, making a great contribution to the superior pyroelectric energy harvesting. The output energy density in one cycle of the BNT‐BA‐0.02KNN is 23.32 μJ/cm3, which is twice as high as that of the pristine samples. The enhancement of material properties suggests that the pyroelectric energy harvesting can be efficiently optimized by the adequate control of the phase structure. [ABSTRACT FROM AUTHOR]

In order to study the coefficient of restitution (Cr) during the vibrational separation of maggots, which were provided by Hubei Province Insect Resource Utilization and Pest Sustainable Management Key Laboratory, based on kinematic principles, a series of collision experiments were conducted. The maximum force that a maggot can withstand was tested. A range of free-falling heights on collision was analyzed. The L8 (41×24) orthogonal table scheme was designed to analyze the four influential factors: collision material, material thickness, free-falling height and moisture content. The results showed that the maximum force a maggot can withstand is 9.64±0.26 N, where N means Newton, and is the unit of force. The factors influencing Cr are: collision material, free-falling height, material thickness and moisture content. The single-factor test showed that the collision material and the free-falling height were the most influential factors on the Cr of the maggots. [ABSTRACT FROM AUTHOR]

Summary: Chrysomya megacephala is a saprophagous fly whose larvae can compost manure and yield biomass and bio‐fertilizer simultaneously. However, there are concerns for the safety of the composting system, that is risk of diseases spread by way of manure pathogens, residue of harmful metals and emission of greenhouse gases. Microbiota analysis and heavy metal speciation by European Communities Bureau of Reference were evaluated in raw, C. megacephala‐composted and natural stacked swine manure to survey pathogenic bacterial changes and mobility of lead and cadmium in manure after C. megacephala feeding; the emission rate of CH4 and N2O from manure during C. megacephala composting and natural stacking was also measured. C. megacephala composting altered manure microbiota, reduced the risk of pathogenic bacteria and maintained the stability, and microbiota changes might be associated with heavy metal fractions, especially in Pseudomonas and Prevotella. In addition, C. megacephala‐composting significantly reduced the emission rate of CH4 and N2O in comparing with natural stacking situation and the first two days should be the crucial period for CH4 and N2O emission measurement for manure treatment by C. megacephala. Moreover, OTU26 and Betaproteobacteria were changed after C. megacephala composting which might play a role in emission of CH4 and N2O, respectively. [ABSTRACT FROM AUTHOR]

Constructing a porous structure in photocatalysts is an effective strategy for improving the photocatalytic activity because of its enhanced molecule transfer capability and light capturing efficiency. In this work, a hierarchical macro‐/mesoporous ZnS/TiO2 composite with macrochannels was successfully synthesized without using templates by the simple dropwise addition of an ethanol solution of tetrabutyl titanate and zinc acetate into a sodium sulfide aqueous solution, which was then calcined at 450°C. Compared with pure TiO2, the ordered porous ZnS/TiO2 composite exhibited an enhanced photocatalytic activity on methylene blue removal under UV‐light irradiation. The results indicate that the macro‐/mesoporous structure, the large specific surface area, and the heterostructure combination between ZnS and TiO2 play a synergistic effect on the enhanced photocatalytic activity via improving the light absorption and the diffusion of organic molecules, providing more reactive sites for the photocatalytic reaction and improving the separation of photogenerated electron–hole pairs, respectively. Radical trapping experiments demonstrated that holes (h+) and superoxide anion radicals (O2−) play an important role in the photocatalytic oxidation process. [ABSTRACT FROM AUTHOR]

In this paper, through control the precursor's structure with layer morphology, the plate-like particles with different edge length and thickness can be syntheszed by the two step molten salt (MSS) method. The results of SEM showed that the NaNbO3 particles were characterized by platelet-like morphology with an edge length of 10∼20 μm and a thickness of 1∼4 μm. The results of XRD indicated the NaNbO3 particles synthesized had a strong orientation in {0 0 l} crystal planes. The plate-like NaNbO3 particles we synthesized are a suitable template candidate to fabricate textured ceramics by TGG or RTGG method, especially to the textured potassium sodium niobate lead-free piezoelectric ceramics. [ABSTRACT FROM AUTHOR]