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The absorption-dominated graphene porous materials, considered ideal for mitigating electromagnetic pollution, encounter challenges related to intricate structural design. Herein, petal-like graphene porous films with dendritic-like and honeycomb-like pores are prepared by controlling the phase inversion process. The theoretical simulation and experimental results show that PVP K30 modified on the graphene surface via van der Waals interactions promotes graphene to be uniformly enriched on the pore walls. Benefiting from the regulation of graphene distribution and the construction of honeycomb pore structure, when 15 wt % graphene is added, the porous film exhibits absorption-dominated electromagnetic shielding performance, compared with the absence of PVP K30 modification. The total electromagnetic shielding effectiveness is 24.1 dB, an increase of 170%; the electromagnetic reflection coefficient reduces to 2.82 dB; The thermal conductivity reaches 1.1 W/(m K), representing a 104% increase. In addition, the porous film exhibits improved mechanical properties, the tensile strength increases to 6.9 MPa, and the elongation at break increases by 131%. The method adopted in this paper to control the enrichment of graphene in the pore walls during the preparation of honeycomb porous films by the phase inversion method can avoid the agglomeration of graphene and improve the overall performance of the porous graphene porous films.

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This research introduces a new approach to elevate the precision of image edge detection through a new algorithm rooted in the coefficients derived from the subclass SCt,ρ (CSKP model). Our method employs convolution operations on input image pixels, utilizing the CSKP mask window in eight distinct directions, fostering a comprehensive and multi-directional analysis of edge features. To gauge the efficacy of our algorithm, image quality is assessed through perceptually significant metrics, including contrast, correlation, energy, homogeneity, and entropy. The study aims to contribute a valuable tool for diverse applications such as computer vision and medical imaging by presenting a robust and innovative solution to enhance image edge detection. The results demonstrate notable improvements, affirming the potential of the proposed algorithm to advance the current state-of-the-art in image processing.

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In our work, a novel series of europium (III) (Eu3+) (5, 10 and 15 wt %) doped cobalt tetroxide@cupric oxide (Co3O4@CuO) nanomaterials (NMs) were synthesized by facile coprecipitation method. The synthesized NMs were characterized by XRD (X-ray diffraction), FT-IR (Fourier transform infrared), UV (ultraviolet)-visible absorption spectra, XPS (X-ray photoelectron), BET (Brunauer-Emmett-Teller) analytical methods. Crystal structure studies revealed the formation of polycrystalline nature with monoclinic and cubic phase. The morphology studies of Eu3+x:Co3O4@CuO (x = 5, 10 and 15 wt %) showed petal shape nanoparticles (NPs) with agglomeration. Redshift in optical absorption spectra appeared with a significant impact on the optical band gap as Eu3+ concentration increases on Co3O4@CuO bimetallic oxide NMs. The chemical composition and valence state of the elements confirmed from XPS studies detected the presence of Eu, Cu, Co, O and C elements. An increase in the pore size and surface area resulted as the Eu3+ concentration increased on Co3O4@CuO NMs. However, room temperature photoluminescence (RTPL) spectra of Co3O4@CuO bimetallic oxide NMs at two different excitations (λ excitation = 280 nm, 320 nm) showed sharp, strong emission intensities located at near ultraviolet (NUV) region and weak emissions detected at far ultraviolet (FUV) regions of the RTPL spectrum. Further, visible range emission intensities were displayed by Eu3+:Co3O4@CuO (5, 10 and 15 wt %) NMs when exited at 280 nm. The characteristic white light emission peaks in the visible range of the RTPL spectra showed intense blue, green and orange colours. Emission intensity increases with an increase in Eu3+ concentration on Co3O4@CuO bimetallic oxide NMs. The fluorescence (FL) decay spectra of Eu3+ 10wt% and 15 wt%: Co3O4@CuO NMs showed a decay lifetime of 2.54 and 2.31 ns (ns) attributed to the dynamic, ultrafast excitation energy transfer between Eu3+ (dopant) and Co3O4@CuO (host) NMs. It is proposed that enhanced RTPL emission intensity and FL decay behavior of Eu3+x:Co3O4@CuO NMs closely related to the change in the optical band gap, variation in the crystallite size, formation of more number of oxygen vacancies in the crystal structure of hybrid nanomaterials.

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A novel nano petal-shaped covalent organic frameworks modified magnetic polystyrene-divinylbenzene-glycidylmethacrylate (NP-COF@Mag-PS/DVB/GMA) microsphere has been synthesized. It is a perfect combination of high productivity of PS/DVB/GMA microspheres and excellent enrichment efficiency of COF particles, and the excellent properties of NP-COF@Mag-PS/DVB/GMA microspheres are characterized by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) and X-ray photoelectron spectroscopy (XPS). The sorbent can extract illicit drugs via the reverse-phase interactions provided by benzene ring on the polymer backbone and the hydrogen bonding interactions provided by functional group (-NH-) on the COF particles. Based on using NP-COF@Mag-PS/DVB/GMA as sorbents, an easiness-to-handle of magnetic dispersive solid phase extraction (Mag-dSPE) procedure is proposed for the simultaneous preconcentration of 12 illicit drugs from wastewater. The obtained results show high extraction efficiency of NP-COF@Mag-PS/DVB/GMA to illicit drugs with recoveries between 81.6 and 116%. Furthermore, a liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS) method for the determination of 12 illicit drugs from wastewater at sub-ppt levels has been proposed and validated with the pretreatment of samples by Mag-dSPE. The limits of quantification (LOQs) for the 12 illicit drugs are between 0.40 and 4.90 ng/L. Validation results on linearity, specificity, trueness and precision, as well as on application to the analysis of 12 illicit drugs in ten real samples demonstrate the applicability to environment monitoring analysis.

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The synthetic jet piezoelectric air pump is a potential miniature device for electronic cooling. In order to improve the performance of the device, a small-sized synthetic jet piezoelectric air pump is proposed in this work, which is mainly characterized by petal-shaped inlet channels. First, the structure and working principle of the piezoelectric vibrator and the proposed pump are analyzed. Then, three synthetic jet piezoelectric air pumps with different inlet channels are compared. These inlets are the direct channels, the diffuser/nozzle channels, and the petal-shaped channels, respectively. Furthermore, the performance of the synthetic jet piezoelectric air pump with the petal-shaped inlet channels is optimized by orthogonal tests. Finally, the simulation was used to investigate the heat dissipation capability of the synthetic jet piezoelectric pump. The experimental results show that among the three inlet channels, the petal-shaped channel can greatly improve the performance of the pump. The unoptimized pump with petal-shaped channels has a maximum flow rate of 1.8929 L/min at 100 V, 3.9 kHz. Additionally, the optimized pump with petal-shaped channels reaches a maximum flow rate of 3.0088 L/min at 100 V, 3.7 kHz, which is 58.95% higher than the unoptimized one. The proposed synthetic jet piezoelectric air pump greatly improves the output performance and has the advantages of simple structure, low cost, and easy integration. The convective heat transfer coefficient of the synthetic jet piezoelectric pump is 28.8 W/(m2·°C), which can prove that the device has a better heat dissipation capability.

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Here, the novel petal-shaped ionic liquids modified covalent organic frameworks (PS-IL-COFs) particles have been synthesized by using ionic liquids as modifying agent, which could be beneficial to avoid the aggregation of COFs during the preparation and improve its dispersing performance. The novel PS-IL-COFs particles have been used and evaluated in the one step cleanup and extraction (OSCE) procedure for human plasma prior to the analysis of 3 general anesthetics by liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS). In the OSCE procedure, human plasma samples are directly mixed with extraction solvent and PS-IL-COFs particles, and the extraction and cleanup procedure have been carried out simultaneously. Compared with the Oasis PRiME HLB cartridge method, the OSCE procedure using PS-IL-COFs particles as sorbents is much more effective for the minimization of ion suppression resulted from blood phospholipids. Under optimal conditions, the PS-IL-COFs particles show higher cleanup efficiency of 3 general anesthetics with recoveries in the range of 82.5%-115%. The limits of quantification (LOQs) for propofol, ketamine and etomidate are 0.18 µg/L, 0.15 µg/L and 0.016 µg/L, respectively. Validation results on linearity, specificity, precision and trueness, as well as on the application to analysis of general anesthetics in a case of a 54-year-old female suffered gallstone demonstrate the applicability to clinical studies.

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