To extend the working life of products made of titanium alloy, it is necessary to improve the polishing method to diminish the remaining defects on the workpiece surface. The Halbach array-assisted magnetic abrasive particle polishing method for titanium alloy was employed in this work. The distribution of magnetic field strength was simulated and verified at first to learn the characteristics of the Halbach array used in this work. Then, the polishing performance of the polishing tool was studied by conducting the polishing test, which aimed to display the relationship between shear force and surface roughness with polishing time, and the surface morphology during polishing was also analyzed. Following the establishment of the response surface model, a study on the optimal polishing parameters was conducted to obtain the suitable parameters for maximum shear force and minimum surface roughness. The results show that the maximum shear force 6.11 N and minimum surface roughness Sa 88 nm can be attained, respectively, under the conditions of (1) polishing tool speed of 724.254 r·min-1, working gap of 0.5 mm, and abrasive particle size of 200 μm; and (2) polishing tool speed of 897.87 r·min-1, working gap of 0.52 mm, and abrasive particle size of 160 μm.

Chitosan, a biopolymer obtained from chitin, is known for its remarkable adsorption abilities for dyes, drugs, and fats, and its diverse array of antibacterial characteristics. This study explores the extraction and characterization of chitosan from the mycelium of Amanita phalloides. The moisture content, ash content, water binding capacity, fat binding capacity, and degree of deacetylation of the extracted chitosan were determined. The chitosan exhibited a high yield of 70%, crystallinity of 49.07%, a degree of deacetylation of 86%, and potent antimicrobial properties against both Gram-negative and Gram-positive bacteria. The study also examined the adsorption capabilities of chitosan to remove methylene blue (MB) dye by analysing specific factors like pH, reaction time, and MB concentration using the response surface model. The highest degree of MB dye removal was 91.6% at a pH of 6, a reaction time of around 60 min and an initial dye concentration of 16 ppm. This experimental design can be applied for chitosan adsorption of other organic compounds such as dyes, proteins, drugs, and fats.

Grape pomace is the main by-product obtained from wine production that is still enriched in bioactive compounds. Within a framework of waste/by-product reuse through a sustainable approach, various green methods were utilized in this work to recover anthocyanins from the pomace resulting from \"Sangiovese\" grape vinification. Ultrasound- and Microwave-Assisted Extractions (UAE and MAE) were coupled with the use of green solvents, such as acidified water, an ethanol/water mixture, and Natural Deep Eutectic Solvents (NaDES), and their efficacy was compared with that of a conventional method based on a methanol/acidified water mixture. The Total Anthocyanin Index ranged from 36.9 to 75.2 mg/g DW for UAE, and from 54.4 to 99.6 mg/g DW for MAE, while resulting in 47.1 mg/g DW for conventional extraction. A Design of Experiments (DoE) approach was applied to MAE, the most efficient technique. Temperature, time, and the solid-to-liquid ratio were set as X variables, while malvidin-3-O-glucoside content and antioxidant activity were used as response variables, measured by High-Performance Liquid Chromatography with Diode Array Detection (HPLC-DAD) and 2,2-Diphenyl-1-picrylhydrazyl (DPPH) assay, respectively. The correlation between temperature and time and the antioxidant activity of the extract was positive, while it was found to be negative when considering malvidin-3-O-glucoside concentration as a response variable. Thus, the optimal conditions in temperature, time and solid-to-liquid ratio were different depending on the chosen variable. The results underline the importance of selecting an accurate response when using the response surface methodology approach.

Response surface models (RSMs) are a new trend in modern anesthesia. RSMs have demonstrated significant applicability in the field of anesthesia. However, the comparative analysis between RSMs and logistic regression (LR) in different surgeries remains relatively limited in the current literature. We hypothesized that using a total intravenous anesthesia (TIVA) technique with the response surface model (RSM) and logistic regression (LR) would predict the emergence from anesthesia in patients undergoing video-assisted thoracotomy surgery (VATS). This study aimed to prove that LR, like the RSM, can be used to improve patient safety and achieve enhanced recovery after surgery (ERAS). This was a prospective, observational study with data reanalysis. Twenty-nine patients (American Society of Anesthesiologists (ASA) class II and III) who underwent VATS for elective pulmonary or mediastinal surgery under TIVA were enrolled. We monitored the emergence from anesthesia, and the precise time point of regained response (RR) was noted. The influence of varying concentrations was examined and incorporated into both the RSM and LR. The receiver operating characteristic (ROC) curve area for Greco and LR models was 0.979 (confidence interval: 0.987 to 0.990) and 0.989 (confidence interval: 0.989 to 0.990), respectively. The two models had no significant differences in predicting the probability of regaining response. In conclusion, the LR model was effective and can be applied to patients undergoing VATS or other procedures of similar modalities. Furthermore, the RSM is significantly more sophisticated and has an accuracy similar to that of the LR model; however, the LR model is more accessible. Therefore, the LR model is a simpler tool for predicting arousal in patients undergoing VATS under TIVA with Remifentanil and Propofol.

The synthesis of cationic polyacrylamides (CPAMs) with the desired cationic degree and molecular weight is essential for various industries, including wastewater treatment, mining, paper, cosmetic chemistry, and others. Previous studies have already demonstrated methods to optimize synthesis conditions to obtain high-molecular-weight CPAM emulsions and the effects of cationic degrees on flocculation processes. However, the optimization of input parameters to obtain CPAMs with the desired cationic degrees has not been discussed. Traditional optimization methods are time-consuming and costly when it comes to on-site CPAM production because the input parameters of CPAM synthesis are optimized using single-factor experiments. In this study, we utilized the response surface methodology to optimize the synthesis conditions, specifically the monomer concentration, the content of the cationic monomer, and the content of the initiator, to obtain CPAMs with the desired cationic degrees. This approach overcomes the drawbacks of traditional optimization methods. We successfully synthesized three CPAM emulsions with a wide range of cationic degrees: low (21.85%), medium (40.25%), and high (71.17%) levels of cationic degree. The optimized conditions for these CPAMs were as follows: monomer concentration of 25%, content of monomer cation of 22.5%, 44.41%, and 77.61%, respectively, and initiator content of 0.475%, 0.48%, and 0.59%, respectively. The developed models can be utilized to quickly optimize conditions for synthesizing CPAM emulsions with different cationic degrees to meet the demands of wastewater treatment applications. The synthesized CPAM products performed effectively in wastewater treatment, with the treated wastewater meeting the technical regulation parameters. 1H-NMR, FTIR, SEM, BET, dynamic light scattering, and gel permeation chromatography were employed to confirm the structure and surface of the polymers.

To popularize the complete replacement of natural sand with manufactured sand, a study was performed to determine the effect of adding polypropylene fibres (PPFs) to increase the bending strength and carbonization resistance of manufactured sand concrete (MSC). A 2 × 3 factorial design with the content and length of PPF as variables was used to establish a carbonization depth prediction model and a response surface model (RSM). The phase composition and microstructure of polypropylene-fibre-reinforced manufactured sand concrete (PPF-MSC) were analysed using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show the addition of PPF with different contents and lengths increases the bending strength of PPF-MSC to varying degrees, while reducing the carbonization depth and increasing the dynamic elastic modulus after 28 days of carbonization. The highest bending strength (6.12 MPa) and carbonization resistance of PPF-MSC are obtained by the addition of 1 kg/m3 of 12 mm PPF, while the carbonization depth and an increase in the dynamic elastic modulus after 28 days of carbonization are maintained at a minimum of 2.26% and 1.94 mm, respectively. A prediction model was established to obtain a formula for the PPF-MSC carbonization depth in terms of the content and length of PPF and the carbonization time. The following results were obtained from the RSM: compared to the PPF length, the PPF content has a larger impact on the PPF-MSC bending strength and a smaller impact on the PPF-MSC carbonization resistance; there is no significant interaction between the content and length of PPF; and the predicted and measured values are close, indicating that the model is highly reliable. A comparison of the XRD patterns and SEM micrographs of PPF-MSC and MSC after 28 days of carbonization show a lower peak intensity of CaCO3 in the pattern for the carbonized area for PPF-MSC than for MSC and considerably fewer surface pores and cracks in PPF-MSC than in MSC. These results indicate that the addition of PPF increases the compactness of MSC and creates an effective resistance to the erosion by water molecules and carbon dioxide (CO2), thus enhancing the bending strength and carbonization resistance of MSC.

Dispersive liquid-liquid microextraction was used in conjunction with liquid chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry to quantitate vitamins K1 and K2 in vitamin-fortified emulsions, and vital microextraction parameters were optimized using response surface methodology coupled with Box-Behnken design. Under optimal microextraction conditions, highly linear (R 2 > .999) calibration curves were obtained for both vitamins in a broad concentration range (1-1000 μg/L), and vitamin recoveries exceeded 90%. The detection and quantitation limits equaled 1.89 and 5.72 μg/L for vitamin K1, respectively, and 5.00 and 15.15 μg/L for vitamin K2, respectively. When applied to vitamin-K-loaded nanoemulsions and solid lipid nanoparticles, the developed method achieved excellent results, outperforming the currently employed Korean Food Code method, and therefore holding great promise for the quantitation of vitamin K in vitamin-fortified food products.

A mixed natural preservative composed of ε-polylysine (ε-PL), chestnut 70% ethanol extract (NE), and cinnamon hydrothermal extract (CW), was investigated for the reduction of Staphylococcus aureus. The minimum inhibitory concentration (MIC) and minimum bacterial concentration (MBC) of seven natural extracts were investigated against a cocktail of three strains of S. aureus (ATCC 25923, ATCC 33591, and ATCC 33594). Three important factors (ε-PL, NE, and CW) were selected by using the Plackett-Burman (PB) design for the response surface model (P < 0.001). Following a central composite design, S. aureus were treated with mixtures of natural preservatives that included ε-PL, NE, and CW. The MIC and MBC of ε-PL and the natural extracts and ranged from 1 to 16 mg/mL (R2 = 0.9857). The mixed natural preservative presented a synergistic antibacterial effect, at the optimum point. These results suggest that mixed natural preservatives of ε-PL, NE, and CW can lower the economic cost of food processing.

There is unprecedented increase in low-temperature stress (LTS) during post-heading stages in rice as a consequence of the recent climate changes. Quantifying the effect of LTS on yields is key to unraveling the impact of climatic changes on crop production, and therefore developing corresponding mitigation strategies. The present research was conducted to analyze and quantify the effect of post-heading LTS on rice yields as well as yield and grain filling related parameters. A two-year experiment was conducted during rice growing season of 2018 and 2019 using two Japonica cultivars (Huaidao 5 and Nanjing 46) with different low-temperature sensitivities, at four daily minimum/maximum temperature regimes of 21/27 °C (T1), 17/23 °C (T2), 13/19 °C (T3) and 9/15 °C (T4). These temperature treatments were performed for 3 (D1), 6 (D2) or 9 days (D3), at both flowering and grain filling stages. We found LTS for 3 days had no significant effect on grain yield, even when the daily mean temperature was as low as 12 °C. However, LTS of between 6 and 9 days at flowering but not at filling stage significantly reduced grain yield of both cultivars. Comparatively, Huaidao 5 was more cold tolerant than Nanjing 46. LTS at flowering and grain filling stages significantly reduced both maximum and mean grain filling rates. Moreover, LTS prolonged the grain filling duration of both cultivars. Additionally, there was a strong correlation between yield loss and spikelet fertility, spikelet weight at maturity, grain filling duration as well as mean and maximum grain filling rates under post-heading LTS (p < 0.001). Moreover, the effect of post-heading LTS on rice yield can be well quantified by integrating the canopy temperature (CT) based accumulated cold degree days (ACDDCT) with the response surface model. The findings of this research are useful in modeling rice productivity under LTS and for predicting rice productivity under future climates.

Acridine orange (AO), a basic carcinogenic fluorochrome dye, is used in the industry for staining. In this study, Gram-positive bacteria, Bacillus cereus M116 (MTCC 5521) dry biomass was tested as an eco-friendly, easily available, and cheap biosorbent for the AO dye removal. We obtained optimum biosorption of AO at a biomass concentration of 0.25 g/L and initial dye concentrations of 50-400 mg/L at neutral to basic pH within the 300 min contact time. Kinetics analysis of the biosorption process was best fitted with the pseudo-second-order reaction type. We also performed the isotherm analysis to predict the nature of the reaction taking place, which was found to follow the Redlich Peterson isotherm model with high determination coefficients. The maximum sorption capacity was 210.46 mg/g of dry biomass. The differential FTIR spectroscopic analysis of pristine and AO-treated Bacillus cereus M116 cells suggested the potential involvement of carbonyl, hydroxyl, and amine groups in the biosorption process. Also, the scanning electron microscopy of the cells after AO removal confirmed a gross surface alteration compared to the untreated cells. Furthermore, Response Surface Model (RSM) analysis with the three-way ANOVA test confirms statistically significant interactions between the dye concentration, pH, and temperature with the biosorption capacity (p < 0.001). Hence, the dry biomass of Bacillus cereus M116 was found to be an effective bio-remedial for the AO removal.