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Surfactant-free microemulsions (SFMEs) have been explored extensively to avoid the residual surfactant problem caused by traditional surfactant microemulsions. Many researchers focused on the SFMEs with tertiary amine, which exhibited the typical CO2 response behavior. In this study, the phase diagram of the SFMEs consisting of tripropylamine (TPA), ethanol, and water was readily prepared via the measurements of electrical conductivity. The CO2 response behavior of SFME was confirmed by determination of conductivity and measurement of the average diameter of SFME, which was mainly dependent on the protonation of TPA induced by the additional CO2. The transition of protonated TPA to a more hydrophilic nature from lipophilicity to hydrophilicity should be responsible for the variation of SFME average diameter. In addition, the SFMEs exhibited remarkable solubilizing capacity of crude oil, and three types of SFMEs achieved more than 80% oil removal rate in the washing process of oil sands. It was noted that both oil-in-water and bicontinuous SFMEs could be circularly utilized at least three times with a relatively high oil removal rate (%). Our work provided the insight perspective on the mechanism of SFMEs with a CO2 response behavior.
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Optical phased arrays (OPAs) can achieve non-mechanical beam deflection. Many types of OPA face the problem of low deflection efficiency due to the phase distortion induced by mutual coupling between nearby channels. In this Letter, a universal optimization algorithm is proposed to compensate for this structural phase distortion, in which the adjacent sampling principal component analysis (AS-PCA) method is introduced to reduce the dimension of the solution space. Simulations and experimental results on different classes of OPA verified that this method can considerably optimize the deflection beam with a rapid convergence speed, irrespective of the scale of OPA, and maintain the universal feature, laying the foundation for large-scale, high-density OPA in-line optimization. We envision it to become a general method on different platforms.
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A novel electrochemical sensor is described for the determination of ofloxacin (OFL) in environmental water samples. A laser-modified glassy carbon electrode (LGCE) was structured and characterized by scanning electron microscopy, atomic force microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and electrochemical impedance spectroscopy. The increase in electrochemical activity is due to a moderate increase in the surface roughness and to the presence of functional groups on the LGCE. Under optimal conditions (viz. a pH value of 5.5, a laser power of 1.8 W and an action time of 40 s), the sensor is capable of detecting OFL by differential pulse voltammetry at a working potential of +0.91 V (versus Ag/AgCl). Response is linear from 0.25 to 200 µM for OFL concentration range, and the detection limit is 75 nM (at S/N = 3). Removal of oxygen from samples is not required. The sensor was successfully applied to the determination of OFL in spiked groundwater, tap water and wastewater samples, with apparent recoveries from 94.0 to 108.0% and a relative standard deviation of less than 4.8%." Graphical abstractSchematic representation of a method for determination of ofloxacin (OFL) by differential pulse voltammetry. It is making use of a laser modified glassy carbon electrode (LGCE), which increases the number of active functional groups and the surface area compared to a conventional GCE.
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A hybrid integration of nanoporous gold with silicon nitride waveguide has been realized for surface-enhanced Raman spectroscopy (SERS) at 633-nm wavelength. The SERS signal is excited through 580-nm-thick T-shape suspended waveguides and collected through an objective lens. Raman spectra for different mesa width at either transverse electric (TE) or transverse magnetic (TM) mode are measured and compared. The localized surface plasmon resonance of the nanoporous gold can result in a waveguide and polarization-dependent SERS enhancement. The presented miniaturized SERS chips can work from visible to near-infrared wavelength and a wide application prospect could be expected.
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This study was to analyze application effect of multidisciplinary collaboration model with health-care integration in perioperative period of femoral neck fracture. As a prospective study, 124 patients with femoral neck fracture who underwent artificial joint replacement in our hospital from August 2020 to August 2021 were selected as the study subjects. According to the random allocation, they were divided into the group A (n = 62, multidisciplinary collaboration model with health-care integration) and the group B (n = 62, conventional care) to analyze the clinical value of different intervention measures in perioperative period by comparing the hip joint activity, quality of life and incidence of perioperative complications between the two groups. Compared with group B, the average HHS score and hip joint activity after intervention in group A were notably higher (P < 0.05), the VAS score after intervention was overtly lower (P < 0.001), and the GQOLI-74 score of group A after intervention was visibly higher (P < 0.001), with no overt difference in the overall incidence of perioperative complications between the two groups (P > 0.05). The application of multidisciplinary collaboration model with health-care integration in femoral neck fracture can effectively improve the hip joint function, reduce the severity of pain and benefit patients, and further studies will help to establish a better solution for such patients.
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The application of rectangular-groove fused-silica gratings as polarizing beam splitters (PBSs) under Littrow incidence is investigated. Based on the simple modal method, two different cases of PBS gratings are designed. The achieved solutions, which are independent on the incident wavelength, are verified by the rigorous coupled-wave analysis and expressed in several polynomials instead of listing one or two numerical solutions. More importantly, on the basis of the designed PBS gratings, a porous fused silica antireflective film is introduced to improve their performances. Theoretical results indicate that such modified rectangular-groove PBS gratings exhibit higher diffraction efficiencies (over 0.99) and larger spectral bandwidths.
Assuntos
Refratometria/instrumentação , Dióxido de Silício/química , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de EquipamentoRESUMO
In the present study, we aimed to investigate the preventive effects of 4-hydroxychalcone (4HCH) on resistant hypertension. We used cryptochrome-null mice, which characteristically show high plasma aldosterone levels, inflammation, and renal injury. The cryptochrome-null mice received high-salt treatment and were treated orally with 4HCH 10 mg/kg, 4HCH 20 mg/kg, and 4HCH 40 mg/kg, respectively. The salt administration in cryptochrome-null mice is able to induce an increase in systolic pressure which is associated with hyperaldosteronism, inflammation, and kidney injury. Treatment with 40 mg/kg 4HCH reduced systolic hypertension, serum IL-1ß, and TNF-α levels and suppressed the activation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and renal injury. The impact of 4HCH on the hyperaldosteronism, inflammation, and kidney injury provides new insights for future development of therapeutic strategies in resistant hypertension.