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The paper proposes an ultra-narrow band graphene refractive index sensor, consisting of a patterned graphene layer on the top, a dielectric layer of SiO2 in the middle, and a bottom Au layer. The absorption sensor achieves the absorption efficiency of 99.41% and 99.22% at 5.664 THz and 8.062 THz, with the absorption bandwidths 0.0171 THz and 0.0152 THz, respectively. Compared with noble metal absorbers, our graphene absorber can achieve tunability by adjusting the Fermi level and relaxation time of the graphene layer with the geometry of the absorber unchanged, which greatly saves the manufacturing cost. The results show that the sensor has the properties of polarization-independence and large-angle insensitivity due to the symmetric structure. In addition, the practical application of testing the content of hemoglobin biomolecules was conducted, the frequency of first resonance mode shows a shift of 0.017 THz, and the second resonance mode has a shift of 0.016 THz, demonstrating the good frequency sensitivity of our sensor. The S (sensitivities) of the sensor were calculated at 875 GHz/RIU and 775 GHz/RIU, and quality factors FOM (Figure of Merit) are 26.51 and 18.90, respectively; and the minimum limit of detection is 0.04. By comparing with previous similar sensors, our sensor has better sensing performance, which can be applied to photon detection in the terahertz band, biochemical sensing, and other fields.

The NiWO4 powder was prepared by combining the hydrothermal method with calcination. Several studies have demonstrated that the NiWO4/graphene oxide composite can enhance the electrochemical performance of the NiWO4 material. However, no studies have investigated the use of NiWO4/graphene oxide composite material as the cathode material in zinc-ion batteries. The successful preparation of the NiWO4/graphene oxide composite material is verified by various characterization techniques. The NiWO4/graphene oxide composite, which is meant to be a cathode material, is fabricated into electrode sheets and incorporated into CR2025 coin cells for electrochemical assessment. The experimental results indicate that the material exhibits a high charge–discharge specific capacity with high rates. At a current density of 0.1 A g−1, it has a specific capacity of 490.2 mA h g−1. Even after 2000 charge–discharge cycles at a current density of 1 A g−1, the capacity remains constant at 75.2%. Through calculations, it is found that the charge storage is mainly contributed to by pseudocapacitance.

The thiosemicarbazone derivatives have a wide range of biological activities, such as antioxidant activity. In this study, the antiradical activities of six camphene-based thiosemicarbazones (TSC-1~6) were investigated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and peroxyl radical scavenging capacity (PSC) assays, respectively, and the results reveal that TSC1~6 exhibited good abilities for scavenging free radicals in a dose-dependent way. Compound TSC-2 exhibited the best effect of scavenging DPPH radical, with the lowest EC50 (0.208 ± 0.004 mol/mol DPPH) as well as the highest bimolecular rate constant Kb (4218 M−1 s−1), which is 1.18-fold higher than that of Trolox. Meanwhile, TSC-2 also obtained the lowest EC50 (1.27 µmol of Trolox equiv/µmol) of scavenging peroxyl radical. Furthermore, the density functional theory (DFT) calculation was carried out to further explain the experimental results by calculating several molecular descriptors associated with radical scavenging activity. These theoretical data suggested that the electron-donating effect of the diethylamino group in TSC-2 leads to the enhancement of the scavenging activities and the studied compounds may prefer to undergo the hydrogen atom transfer process.

A series of novel pinanyl pyrimidine amine derivatives (1e~1n) and camphoryl pyrimidine amine derivatives (2b~2f) bearing bicyclic monoterpene moieties were designed and synthesized from natural and renewable nopinone and camphor. All chemical structures of target compounds were characterized by 1H NMR, 13C NMR and HRMS spectra analyses, and the antimicrobial activities were evaluated. The results indicated that most compounds showed considerable antibacterial and antifungal activities against Klebsiella pneumoniae, Streptococcus pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Methicillin-Resistant Staphylococcus aureus (MRSA), Bacillus cereus and Candida albicans. Among them, 1f showed potent antibacterial activity against all tested bacteria, 1i exhibited excellent inhibition against Streptococcus pneumoniae (1 μg/mL) and Escherichia coli (1 μg/mL), which was better than the control drug amikacin (2 μg/mL). As to antifungal activity against Candida albicans (C. albicans), compound 1l showed comparable activity (16 μg/mL) to the control drug ketoconazole. Furthermore, five active compounds with better antimicrobial activities also showed anti-inflammatory potencies against mouse mononuclear macrophages leukemia cells (RAW). Especially, 1f (IC50 = 1.37 μM) and 2f (IC50 = 1.87μM) are more potent than the control drug aspirin (IC50 = 1.91 μM).

A carbon quantum dot (CQDs)/Ag3PO4/BiPO4 heterostructure photocatalyst was constructed by a simple hydrothermal synthesis method. The as-prepared CQDs/Ag3PO4/BiPO4 photocatalyst has been characterized in detail by X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, ultraviolet–visible spectroscopy, and photoelectrochemical measurements. It is demonstrated that the CQDs/Ag3PO4/BiPO4 composite is constructed by assembling Ag3PO4 fine particles and CQDs on the surface of rice-like BiPO4 granules. The CQDs/Ag3PO4/BiPO4 heterostructure photocatalyst exhibits a higher photocatalytic activity for the degradation of the rhodamine B dye than that of Ag3PO4, BiPO4, and Ag3PO4/BiPO4. The synergistic effects of light absorption capacity, band edge position, separation, and utilization efficiency of photogenerated carriers play the key role for the enhanced photodegradation of the rhodamine B dye.

By employing a synergistic blend of experimental and theoretical methodologies, we investigated the corrosion inhibition efficacy of a synthesized pyrazole derivative (BM-01) in a solution of hydrochloric acid (1 M). We utilized molecular dynamics (MD) simulations, scanning electron microscopy (SEM), density functional theory (DFT), complexation, plus electrochemical impedance spectroscopy (EIS). We conducted weight loss (WL) measurements from 298 to 328 K. Inhibition efficacy reached a maximum at a BM-01 concentration of 10 −3  M, achieving 90.0% (EIS), 90.40% (WL), and 90.38% (potentiodynamic polarization (PDP)). SEM unveiled the shielding of the carbon-steel surface from acid-induced damage by BM-01. The Langmuir adsorption isotherm exhibited a robust fit with a low sum of squares, standard deviation, and a high correlation coefficient. PDP findings indicated that BM-01 acted as a mixed-type inhibitor, predominantly favoring the cathodic process, suggesting potential corrosion-mitigation properties. Theoretical analyses involving DFT, MD simulations, and radial distribution function were conducted to postulate a mechanism and identify an inhibitory layer. Theoretical outcomes aligned closely with experimental data, thereby reinforcing the validity of our findings.

Isolongifolenone, a natural sesquiterpenoid widely used in food additives and perfume, demonstrates a range of biological activities. In this study, a series of isolongifolenone-based caprolactam derivatives (E1–E19) were designed, synthesized, and evaluated for their anticancer activities in vitro. Most of the synthesized compounds significantly inhibited the proliferation of cultured cancer cells. Compound E10, containing an m-trifluoromethyl group, demonstrated the strongest anti-proliferation activities against MCF-7 (IC50 = 0.32 µM), HepG2 (IC50 = 1.36 µM), and A549 (IC50 = 1.39 µM) cells. Moreover, E10 was shown to increase intracellular ROS, reduce mitochondrial function, and induce cancer cell apoptosis via the p53/mTOR/autophagy pathway. Together, these results indicate that compound E10 induced autophagy-associated cell apoptosis in MCF-7 cancer cells. Additionally, the antitumor activity of E10 was validated in a zebrafish MCF-7 xenograft model. The observation that E10 exhibits potent antitumor activity in both a three-dimensional (3D) cell culture model and the zebrafish xenograft model supports the development of E10 as a potential drug candidate for cancer therapy.

This study demonstrates the synthesis of the MgWO4 nanoparticles by a gamma-ray irradiation assisted polyacrylamide gel method through using the citric acid as chelating agent and H2WO4 and Mg(NO3)2·6H2O as starting materials. The anorthic MgWO4 phase can be prepared at a sintering temperature of 600 °C. As the calcination temperature is above 800 °C, a mixed phase including anorthic and monoclinic MgWO4 phases are observed. The prepared MgWO4 particles are almost spherical and the particle size increases with the increasing of sintering temperature. The optical and photoluminescence properties of the MgWO4 nanoparticles change appears to be strongly dependent on the calcining temperature and phase transition. The photoluminescence spectra show that a major emission band around 430 nm is observed when the excitation wavelength is 340 nm of the MgWO4 xerogel powders calcined at below 600 °C. The intensity of emission peak at 430 nm decreases with the decreasing of sintering temperature. In addition, a major emission band around 468 nm is observed when the excitation wavelength is 280 nm of the MgWO4 xerogel powders calcined at above 700 °C. The intensity of emission peak at 468 nm increases with the increasing of sintering temperature. The result confirmed that the anorthic MgWO4 no luminous for the first time. The photofluorescence enhancement of MgWO4 nanoparticles can be attributed to the type-I band alignment.

A series of new quinoxaline derivatives of dehydroabietic acid (DAA) were designed and synthesized as potential antitumor agents. Their structures were characterized by IR, 1H-NMR, 13C-NMR, and MS spectra and elemental analyses. All the new compounds were screened for their in vitro antiproliferative activities against three human cancer cell lines (MCF-7, SMMC-7721 and HeLa) and noncancerous human hepatocyte cells (LO2). A cytotoxic assay manifested that compound 4b showed the most potent cytotoxic activity against the three cancer cell lines, with IC50 values of 1.78 ± 0.36, 0.72 ± 0.09 and 1.08 ± 0.12 μM, respectively, and a substantially lower cytotoxicity to LO2 cells (IC50: 11.09 ± 0.57 μM). Moreover, the cell cycle analysis suggested that compound 4b caused cell cycle arrest of SMMC-7721 cells at the G0/G1 phase. In a Hoechst 33258 staining assay, compound 4b caused considerable morphological changes of the nuclei of SMMC-7721 cells, correlated with cell apoptosis. In addition, an Annexin V-FITC/PI dual staining assay confirmed that compound 4b could induce the apoptosis of SMMC-7721 cells in a dose-dependent manner.

Micro-displacement measurements play a crucial role in many industrial applications. Aiming to address the defects of existing optical-fiber displacement sensors, such as low sensitivity and temperature interference, we propose and demonstrate a novel surface plasmon resonance (SPR)-based optical-fiber micro-displacement sensor with temperature compensation. The sensor consists of a displacement-sensing region (DSR) and a temperature-sensing region (TSR). We employed a graded-index multimode fiber (GI-MMF) to fabricate the DSR and a hetero-core structure fiber to fabricate the TSR. For the DSR, we employed a single-mode fiber (SMF) to change the radial position of the incident beam as displacement. The resonance angle in the DSR is highly sensitive to displacement; thus, the resonance wavelength of the DSR shifts. For the TSR, we employed polydimethylsiloxane (PDMS) as a temperature-sensitive medium, whose refractive index is highly sensitive to temperature; thus, the resonance wavelength of the TSR shifts. The displacement and temperature detection ranges are 0–25 μm and 20–60 °C; the displacement and temperature sensitivities of the DSR are 4.24 nm/μm and −0.19 nm/°C, and those of the TSR are 0.46 nm/μm and −2.485 nm/°C, respectively. Finally, by means of a sensing matrix, the temperature compensation was realized.