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101.
    
Cavity optomechanics explores the interaction between light and mechanical systems through radiation pressure. This interdisciplinary field merges principles from quantum mechanics and quantum optics provides powerful tools for generating and controlling quantum states. In this research, we theoretically investigated a four-level N-atomic system within the context of optomechanics. The oscillating mirror possesses a mass that varies with position and exhibits a singularity. We analyzed the dynamics using Heisenberg–Langevin equations and calculated steady-state solutions, studied optical response through both analytical and numerical methods. The main focus of this study was optical response within the domain of position-dependent effective mass. Our findings revealed that the output field representing transmission exhibits variations and shift with α$$ alpha $$, the nonlinear parameter of the position dependent effective mass. These variations not only impact transmission but also alter the dispersion and phase of the output field.  相似文献   
102.
    
Biodiesel is a potential alternative fuel that offers several environmental benefits and can be used in conventional engines. However, high feedstock cost poses a challenge for its commercial viability. This study focuses on producing biodiesel using waste cooking oil (WCO) and Moringa oleifera oil (MOO) as feedstock, with a specific emphasis on the use of modified conch shell as solid catalyst under ultrasonic conditions. Different mixtures of WCO and MOO were evaluated for their suitability in a two-stage esterification transesterification process, and the acid value of the WCO-MOO blend was reduced through an ultrasound-assisted esterification process. Additionally, a calcium oxide-based catalyst was developed from conch shells (CS) through calcination for 3 h at 900°C and further modified using water and methanol. The characterization studies confirm the successful development and modification of the CS catalyst and also demonstrates excellent catalytic activity. The ultrasound assisted transesterification process parameters were optimized using response surface methodology (RSM) based Box–Behnken design (BBD). By employing a catalyst loading of 5.8 wt%, methanol to esterified oil volumetric ratio of 0.37:1, and an ultrasonication time of 57 min, a maximum predicted methyl ester conversion of 94.7% was achieved. Therefore, this work provides valuable insights into the use of modified conch shell catalyst for biodiesel production from WCO and MOO mixtures thereby contributing to the advancement of cost-effective and environmentally friendly biodiesel production methods.  相似文献   
103.
    
Response surface methodology (RSM) is an expert method for demonstration of effective input factors and responses. In this study, RSM was used with the purpose of increasing the octane number of the primary feed (n-heptane) in n-heptane reforming reaction over Pt/Zr-HMS catalysts. Based on the results of analysis of variance, the correlation coefficient values upper 0.9 were obtained for all responses. However, the results of n-heptane conversion and selectivity to isomers as two responses were fit to Quadratic model and Research Octane Number was fit to Cubic model. Furthermore, the maximum n-heptane conversion of 98.8 was obtained at T = 500°C, TOS = 3.5 h, and Si/Zr = 5. Also, at the optimal conditions of (T = 200°C, TOS = 3.5 h, and Si/Zr = 35) and (T = 500°C, TOS = 1 h, and Si/Zr = 20), the maximum isomers selectivity of 54.2 and RON of 100.0 was obtained, respectively.  相似文献   
104.
105.
A method is developed to fabricate tumor microenvironment (TME) stimuli-responsive nanoplatform for fluorescence (FL) imaging and synergistic cancer therapy via assembling photosensitizer (chlorine e6, Ce6) modified carbon dots (CDs-Ce6) and Cu2+. The as-obtained nanoassemblies (named Cu/CC nanoparticles, NPs) exhibit quenched FL and photosensitization due to the aggregation of CDs-Ce6. Their FL imaging and photodynamic therapy (PDT) functions are recovered efficiently once they entering tumor sites by the stimulation of TME. Introducing of Cu2+ not only provides extra chemodynamic therapy (CDT) function through reaction with hydrogen peroxide (H2O2), but also depletes GSH in tumors by a redox reaction, thus amplifying the intracellular oxidative stress and enhancing the efficacy of reactive oxygen species (ROS) based therapy. Cu/CC NPs can act as a FL imaging guided trimodal synergistic cancer treatment agent by photothermal therapy (PTT), PDT, and thermally amplified CDT.  相似文献   
106.
    
Electrochemical sensing performance is often compromised by electrode biofouling (e.g., proteins nonspecific binding) in complex biological fluids; however, the design and construction of a robust biointerface remains a great challenge. Herein, inspired by nature, we demonstrate a robust polydopamine-engineered biointerfacing, to tailing zwitterionic molecules (i.e., sulfobetaine methacrylate, SBMA) through Michael Addition. The SBMA-PDA biointerface can resist proteins nonspecific binding in complex biological fluids while enhancing interfacial electron transfer and electrochemical stability of the electrode. In addition, this sensing interface can be integrated with tissue-implantable electrode for in vivo analysis with improved sensing performance, preserving ca. 92.0% of the initial sensitivity after 2 h of implantation in brain tissue, showing low acute neuroinflammatory responses and good stability both in normal and in Parkinson′s disease (PD) rat brain tissue.  相似文献   
107.
A novel metal–organic framework material {[N(C2H5)3][Zn2(ptmda)22-H2O)]·(H2O)0.5}n { GUT-3 ; H2ptmda is 4,4′-([p-tolylazanediyl]bis [methylene])dibenzoic acid} was successfully synthesized using the hydrothermal method and characterized by X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. GUT-3 has a two-dimensional network based on dinuclear [Zn2(ptmda)2(μ2-H2O)] building units which formed an eightfold interpenetration network in GUT-3 molecules. Hirshfeld surface analysis revealed that H–H, C–H, and O–H bonds accounted for the majority of intermolecular interactions. Moreover, the interactions between GUT-3 and As(V) – the form of As(V) is AsO43− – were analyzed in aqueous solutions in a batch system to study the effect of pH, concentration, adsorbent dose, adsorption time, adsorption temperature, and shaking speed. The kinetic and isotherm data of arsenic adsorption on GUT-3 were accurately modeled by pseudo-second-order, Langmuir (qm = 33.91 mg/g), and Freundlich models. The Box–Behnken response surface method was used to optimize the adsorption conditions of As(V) from the simulated arsenic-contaminated wastewater. The effect of various experimental parameters and optimal experimental conditions was ascertained using the quadratic model.  相似文献   
108.
    
Developing optimized hydrogel products requires an in-depth understanding of the mechanisms that drive hydrogel tunability. Here, we performed a full 4 × 4 factorial design study investigating the impact of gellan, a naturally derived polysaccharide (1%, 2%, 3%, or 4% w/v) and CaCl2 concentration (1, 3, 7, or 10 mM) on the viscoelastic, swelling, and drug release behavior of gellan hydrogels containing a model drug, vancomycin. These concentrations were chosen to specifically provide insight into gellan hydrogel behavior for formulations utilizing polymer and salt concentrations expanding beyond those commonly reported by previous studies exploring gellan. With increasing gellan and CaCl2 concentration, the hydrogel storage moduli (0.1–100 kPa) followed a power-law relationship and on average these hydrogels had higher liquid absorption capability and greater total drug release over 6 days. We suggest that the effects of gellan and CaCl2 concentration and their interactions on hydrogel properties can be explained by various phenomena that lead to increased swelling and increased resistance to network expansion.  相似文献   
109.
    
Pesticides have posed significant threats to aquatic ecosystems, yet little is known about their transformation products. The challenge is to simultaneously analyze various pesticides and transformation products in water as they have distinct physicochemical properties. A mix‐mode solid phase extraction method was established to simultaneously analyze current‐use pesticides and their transformation products using a mixture of hydrophile–lipophile balance, weak anion, and cation exchange resins (2:1:1, w/w/w) in combination with high‐performance liquid chromatography and tandem mass spectrometry for chemical quantification. Neutral, acidic, and alkaline methanol were used as the elution solvent. Box‐Behnken design was applied to optimize extraction conditions. Optimal conditions were as follows: sorbent mass, 200 mg; volume of elution solvent, 5 mL × 3; pH 4. The method was validated for compounds at concentrations from 20 to 1000 ng/L in different types of water samples, with recovery being from 43.5 ± 3.1 to 141 ± 35%. Low method detection limits (0.02?5.6 ng/L) implied that the developed method was sensitive. Finally, the method was applied to monitor current‐use pesticides and their transformation products in natural waters. Frequent detection of transformation products of pesticides indicated that their contribution to aquatic risk should not be ignored.  相似文献   
110.
    
The activity of Mo/V/W mixed oxide catalyst in the gas phase oxidation of acrolein to acrylic acid is tremendously influenced by addition of fed water. This effect of water is investigated and connected to the catalytic mechanism by several stationary kinetic measurements and transient response methods, such as temperature-programmed reduction, oxidation and desorption experiments, special concentration-programmed methods as well as H218O-SSITKA and D2O-SSITKA experiments. Furthermore, kinetic modeling, based on results of H218O-SSITKA experiments in a wide temperature and feed water content range gives access to kinetic parameters of single reaction steps in the catalytic mechanism. The developed mechanism is not only able to describe conversion and selectivities, inclusively the effect of water, but also describes the 18O-degree of labeling of all reaction components quantitatively.  相似文献   
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