Search

Salted duck egg yolk, a key ingredient in various specialty foods in China, frequently contains broken eggshell fragments embedded in the yolk due to high-speed shell-breaking processes, which pose significant food safety risks. This paper presents an online detection method, YOLOv7-SEY-DeepSORT (salted egg yolk, SEY), designed to integrate an enhanced YOLOv7 with DeepSORT for real-time and accurate identification of salted egg yolks with impurities on production lines. The proposed method utilizes YOLOv7 as the core network, incorporating multiple Coordinate Attention (CA) modules in its Neck section to enhance the extraction of subtle eggshell impurities. To address the impact of imbalanced sample proportions on detection accuracy, the Focal-EIoU loss function is employed, adaptively adjusting bounding box loss values to ensure precise localization of yolks with impurities in images. The backbone network is replaced with the lightweight MobileOne neural network to reduce model parameters and improve real-time detection performance. DeepSORT is used for matching and tracking yolk targets across frames, accommodating rotational variations. Experimental results demonstrate that YOLOv7-SEY-DeepSORT achieves a mean average precision (mAP) of 0.931, reflecting a 0.53% improvement over the original YOLOv7. The method also shows enhanced tracking performance, with Multiple Object Tracking Accuracy (MOTA) and Multiple Object Tracking Precision (MOTP) scores of 87.9% and 73.8%, respectively, representing increases of 17.0% and 9.8% over SORT and 2.9% and 4.7% over Tracktor. Overall, the proposed method balances high detection accuracy with real-time performance, surpassing other mainstream object detection methods in comprehensive performance. Thus, it provides a robust solution for the rapid and accurate detection of defective salted egg yolks and offers a technical foundation and reference for future research on the automated and safe processing of egg products. [ABSTRACT FROM AUTHOR]

In chemical industrial process, conversion of alkenes to functional oxygenates plays a key role in bridging between the feedstock and downstream application. Traditionally, the oxidation required highly‐active oxygen sources or molecular oxygen under high temperature and pressure. This poses challenges to the green and safe production of oxygenates. To circumvent the issues of massive consumption of fossil fuel and serious CO2 footprints, approaches of electro‐oxidation are developed under ambient conditions, adopting O2 and H2O as oxygen source. Utilizing electricity from renewable resources and the involved electron transfer, the performance is closely related to the interface characteristics of electrodes and electrolytes. This review presents the progress in catalysts design, electrolytes optimization, cells integration to effectively regulate the microenvironment of the interfaces. Further discussion of the mechanism analysis and potential issues are emphasized, based on the in‐situ characterization techniques, isotopic experiments and quenching tests. We hope this review can provide an outline for green approaches to oxidation of alkenes via electrocatalytic pathways. [ABSTRACT FROM AUTHOR]

We successfully constructed an ultrathin Ti3C2Tx supported Pt nanocluster catalyst for highly selective and efficient hydrogenation of p-chloronitrobenzene (p-CNB) to p-chloroaniline (p-CAN) under mild conditions (30 °C, 0.1 MPa H2). The Pt/Ti3C2Tx catalyst displayed a very high conversion (>99%) and selectivity (>99%). In addition, a higher reaction rate (41 mol h–1 g–1) was obtained in comparison with the previously reported catalysts. The excellent catalytic activity of Pt/Ti3C2Tx was attributed to the strong metal–support interactions between Pt nanoclusters and the support, in which the electrons were transferred from Ti3C2Tx to Pt sites, affording a high electron density of Pt active sites. Moreover, the electrostatic repulsion between C–Cl moiety and Pt sites inhibited the dechlorination process. In addition, the Pt/Ti3C2Tx catalyst also exhibited excellent performance in substrate scope (reducible heterocyclics such as pyridine and phthalimide), stability (10th cycles, conversion >99% and selectivity 98%), and gram-scale reaction (99% yield, 1.89 g). This work will promote the research in constructing efficient and highly selective noble metal-based catalysts for hydrogenation of halogenated nitroarenes. [ABSTRACT FROM AUTHOR]

Despite of high conductivity and reducing ability, transition metal nanoparticles tend to aggregate and unavoidably impact the selectivity during the proton‐coupled reduction process of CO2RR. New strategy to regulate and utilize the electronic property of transition‐metal particles allows for effective tuning of eCO2RR activity. Through simple creation of N‐doped carbon shells surrounding Ni nanoparticles and controlling the amount and arrangement of the N atoms, successful and long‐lasting electrochemical reduction of CO2 was accomplished. The inherent HER activity was almost completely suppressed. It exhibited FECO above 90 % in a 500 mV potential window, with the optimal up to 96.5 % at −0.78 V vs RHE. In flow cell electrolysis, a current density of 289.4 mA/cm2 was achieved with Faradic efficiency of 96.4 % towards CO. The results of control experiments using different catalysts imply that electron transfer between Ni core and shells was significantly influenced by the property of N atoms. High content of graphitic nitrogen is crucial for the catalytic performance. [ABSTRACT FROM AUTHOR]

In this paper, we investigated the role of excited-state hydrogen bonding in the photocatalytic carbon dioxide reduction reaction (CO2RR) utilizing Rose Bengal as a catalyst, through a combined experimental and theoretical approach. Experiments validated the successful conversion of CO2 to CO in a homogeneous aqueous solution system under light irradiation, without additional photosensitizers or sacrificial agents. Theoretically, the DFT/TDDFT calculations modeled the catalyst-reactants as a hydrogen-bonded complex (HBC), understanding the energy, hydrogen, and electron transfer mechanisms induced by excited-state hydrogen bonding. Combining the photophysical and photochemical insights revealed the complete catalytic cycle, identifying the water oxidation process as the rate-limiting step in the entire photocatalytic CO2RR process. Experimental and computational results provide molecular-level insights into the structure–activity relationships. This work enhances comprehension of the pivotal role of excited-state hydrogen bonding and holds significant reference value for enhancing the conversion efficiency in the photocatalytic CO2RR. [ABSTRACT FROM AUTHOR]

The vascular endothelial growth factor receptor (VEGFR) is a receptor tyrosine kinase that is regarded as an emerging target for abnormal angiogenesis diseases. In this study, novel naphthalene imidazo[1,2-b]pyridazine hybrids as VEGFR selective inhibitors were designed and synthesized using a scaffold hopping strategy based on ponatinib, a multitarget kinase inhibitor. Among the evaluated compounds, derivative 9k (WS-011) demonstrated the most potent inhibitory potency against VEGFR-2 (IC 50  = 8.4 nM) and displayed superior VEGFR selectivity over a panel of 70 kinases compared with ponatinib. Furthermore, 9k possessed good cytotoxic effects on various cancer cell lines, especially the colon cancer HT-29 cells, with an acceptable oral bioavailability. Moreover, 9k significantly inhibited the migration and invasion of human umbilical vein endothelial cells (HUVEC) cells and induced apoptosis through the upregulation of apoptotic proteins in HT-29 cells. 9k also effectively suppressed the activation of VEGFR-2 signaling pathways, which in turn inhibited the growth of HT-29 cells and the tube formation of HUVECs in vitro. All of the findings revealed that 9k could be considered a promising antiangiogenesis lead that merits further investigation., (© 2024 Deutsche Pharmazeutische Gesellschaft.)

Manipulation of selectivity in the catalytic electrochemical carbon dioxide reduction reaction (eCO 2 RR) poses significant challenges due to inevitable structure reconstruction. One approach is to develop effective strategies for controlling reaction pathways to gain a deeper understanding of mechanisms in robust CO 2 RR systems. In this work, by precise introduction of 1,10-phenanthroline as a bidentate ligand modulator, the electronic property of the copper site was effectively regulated, thereby directing selectivity switch. By modification of [Cu 3 (btec)(OH) 2 ] n , the use of [Cu 2 (btec)(phen) 2 ] n ·(H 2 O) n achieved the selectivity switch from ethylene (faradaic efficiency (FE) = 41%, FE C2+ = 67%) to methane (FE CH 4 = 69%). Various in situ spectroscopic characterizations revealed that [Cu 2 (btec)(phen) 2 ] n ·(H 2 O) n promoted the hydrogenation of *CO intermediates, leading to methane generation instead of dimerization to form C 2+ products. Acting as a delocalized π-conjugation scaffold, 1,10-phenanthroline in [Cu 2 (btec)(phen) 2 ] n ·(H 2 O) n helps stabilize Cu δ+ . This work presents a novel approach to regulate the coordination environment of active sites with the aim of selectively modulating the CO 2 RR.

Phonon polaritons, quasiparticles arising from strong coupling between electromagnetic waves and optical phonons, have potential for applications in subdiffraction imaging, sensing, thermal conduction enhancement, and spectroscopy signal enhancement. A new class of phonon polaritons in low-symmetry monoclinic crystals, hyperbolic shear polaritons (HShPs), have been verified recently in β-Ga 2 O 3 by free electron laser (FEL) measurements. However, detailed behaviors of HShPs in β-Ga 2 O 3 nanostructures still remain unknown. Here, by using monochromatic electron energy loss spectroscopy in conjunction with scanning transmission electron microscopy, the experimental observation of multiple HShPs in β-Ga 2 O 3 in the mid-infrared (MIR) and far-infrared (FIR) ranges is reported. HShPs in various β-Ga 2 O 3 nanorods and a β-Ga 2 O 3 nanodisk are excited. The frequency-dependent rotation and shear effect of HShPs reflect on the distribution of EELS signals. The propagation and reflection of HShPs in nanostructures are clarified by simulations of electric field distribution. These findings suggest that, with its tunable broad spectral HShPs, β-Ga 2 O 3 is an excellent candidate for nanophotonic applications., (© 2024 Wiley‐VCH GmbH.)

Nanoscale defects like grain boundaries (GBs) would introduce local phonon modes and affect the bulk materials' thermal, electrical, optical, and mechanical properties. It is highly desirable to correlate the phonon modes and atomic arrangements for individual defects to precisely understand the structure-property relation. Here we investigated the localized phonon modes of Al 2 O 3 GBs by combination of the vibrational electron energy loss spectroscopy (EELS) in scanning transmission electron microscope and density functional perturbation theory (DFPT). The differences between GB and bulk obtained from the vibrational EELS show that the GB exhibited more active vibration at the energy range of <50 meV and >80 meV, and further DFPT results proved the wide distribution of bond lengths at GB are the main factor for the emergence of local phonon modes. This research provides insights into the phonon-defect relation and would be of importance in the design and application of polycrystalline materials.