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1.
Environ Res ; 250: 118419, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38316389

RESUMEN

Ferrous iron (Fe2+) reduces the amount of external carbon source used for the denitrification of low-C/N wastewater. The effects of key operating parameters on the efficiency of ferrous-dependent autotrophic denitrification (FDAD) and the functioning mechanism of the microbiome can provide a regulatory strategy for improving the denitrification efficiency of low C/N wastewater. In this study, the response surface method (RSM) was used to explore the influence of four important parameters-the molar ratio of Fe2+ to NO3--N (Fe/N), total organic carbon (TOC), the molar ratio of inorganic carbon to NO3--N (IC/N) and sludge volume (SV, %)-on the FDAD efficiency. Functional prediction and molecular ecological networks based on high-throughputs sequencing techniques were used to explore changes in the structure, function, and biomarkers of the sludge microbial community. The results showed that Fe/N and TOC were the main parameters affecting FDAD efficiency. Higher concentrations of TOC and high Fe/N ratios provided more electron donors and improved denitrification efficiency, but weakened the importance of biomarkers (Rhodanobacter, Thermomonas, Comamonas, Thauera, Geothrix and unclassified genus of family Gallionellaceae) in the sludge ecological network. When Fe/N > 4, the denitrification efficiency fluctuated significantly. Functional prediction results indicated that genes that dominated N2O and NO reduction and the genes that dominated Fe2+ transport showed a slight decrease in abundance at high Fe/N levels. In light of these findings, we recommend the following optimization ranges of parameters: Fe/N (3.5-4); TOC/N (0.36-0.42); IC/N (3.5-4); and SV (approximately 35%).


Asunto(s)
Procesos Autotróficos , Carbono , Desnitrificación , Hierro , Nitrógeno , Eliminación de Residuos Líquidos , Aguas Residuales , Aguas Residuales/microbiología , Aguas Residuales/química , Carbono/metabolismo , Hierro/metabolismo , Eliminación de Residuos Líquidos/métodos , Nitrógeno/metabolismo , Microbiota , Aguas del Alcantarillado/microbiología
2.
Chem Biodivers ; 21(2): e202301308, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38163260

RESUMEN

Flavonoids, known for their abundance in Eucommia ulmoides pollen, possess diverse biological functions, including antioxidants, antibacterial agents, and anti-tumor properties. This study aims to establish effective parameters for flavonoid extraction from Eucommia ulmoides pollen using a microwave-assisted method, characterize the flavonoid composition of the extracted material, and explore its biological activities. Building upon the initial results from single-factor experiments, response surface methodology was employed to optimize the extraction parameters. The inhibitory effect of human breast cancer cells (MCF-7) was evaluated by CCK assay and Live/dead staining. Simultaneously, the extract's scavenging ability against DPPH free radicals and its antibacterial properties against Escherichia coli and Staphylococcus aureus were investigated. The results demonstrated that the flavonoid yield reached 3.28 g per 100 g of pollen, closely aligning with the predicted value. The IC50 for flavonoid-mediated DPPH radical scavenging was 0.04 mg/mL. The extract exhibited a robust inhibitory effect on both Escherichia coli and Staphylococcus aureus. Concurrently, the extract displayed a significant inhibitory effect on the growth and proliferation of MCF-7 cells in a dose-dependent and time-dependent manner. In addition, six kinds of flavonoids have been identified by UPLC-TOF-MS/MS technology, providing further support to the study on the anti-oxidation and anti-tumor mechanism of Eucommia ulmoides pollen extracts.


Asunto(s)
Eucommiaceae , Humanos , Eucommiaceae/química , Flavonoides/farmacología , Espectrometría de Masas en Tándem , Antioxidantes/farmacología , Antibacterianos/farmacología , Extractos Vegetales/farmacología , Escherichia coli
3.
J Environ Manage ; 370: 122345, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39260279

RESUMEN

Coal mines are one of the largest sources of energy supply and generate significant volumes of wastewater. Chemical coagulation is one of the most effective methods for wastewater treatment. In this research, ferric and aluminum-based coagulants, along with polyacrylamide flocculants with positive, negative, and neutral charges, were utilized in chemical coagulation. After applying the Plackett-Burman screening method, it was found that ferric chloride coagulant, neutral flocculant, and slow mixing duration had the greatest impact. The chemical coagulation process was modeled and optimized by examining these factors using the Box-Behnken statistical design as input parameters and sedimentation velocity as the output. Under optimal conditions, the values for ferric chloride coagulant, neutral flocculant, mixing time in slow mode, and sedimentation velocity were determined to be 106.3 mg/L, 3.98 mg/L, 29.6 min, and 1.10 cm/min, respectively. Under optimal conditions, the removal percentages of pollutants, including TSS, turbidity, TDS, COD, and BOD, were obtained at 100%, 100%, 87%, 93%, and 81%, respectively. The experimental data were fitted using the BBD and ANN methods. Both models demonstrated very high agreement, but the ANN method performed better with an AAD% of 0.66, an MSE of 0.0001, and an R2 value of 0.99. All results were calculated with a confidence level above 98%, indicating that both models had very high reliability in modeling and prediction.

4.
J Environ Manage ; 351: 119761, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38113785

RESUMEN

The practice of aquaculture is associated with the generation of a substantial quantity of effluent. Microalgae must effectively assimilate nitrogen and phosphorus from their surrounding environment for growth. This study modeled the algal biomass film, NO3-N concentration, and pH in the membrane bioreactor using the response surface methodology (RSM) and an artificial neural network (ANN). Furthermore, it was suggested that the optimal condition for each parameter be determined. The results of ANN modeling showed that ANN with a structure of 5-3 and employing the transfer functions tansig-logsig demonstrated the highest level of accuracy. This was evidenced by the obtained values of coefficient (R2) = 0.998, R = 0.999, mean squared error (MAE) = 0.0856, and mean square error (MSE) = 0.143. The ANN model, characterized by a 5-5 structure and employing the tansig-logsig transfer function, demonstrates superior accuracy when predicting the concentration of NO3-N and pH. This is evidenced by the high values of R2 (0.996), R (0.998), MAE (0.00162), and MSE (0.0262). The RSM was afterward employed to maximize the performance of algal film biomass, pH levels, and NO3-N concentrations. The optimal conditions for the algal biomass film were a concentration of 2.884 mg/L and a duration of 6.589 days. Similarly, the most favorable conditions for the NO3-N concentration and pH were 2.984 mg/L and 6.787 days, respectively. Therefore, this research uses non-dominated sorting genetic algorithm II (NSGA II) to find the optimal NO3-N concentration, algal biomass film, and pH for product or process quality. The region has the greatest alkaline pH and lowest NO3-N content.


Asunto(s)
Dióxido de Carbono , Redes Neurales de la Computación , Biomasa , Reactores Biológicos , Concentración de Iones de Hidrógeno
5.
Prep Biochem Biotechnol ; 54(3): 282-293, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37395553

RESUMEN

"Zicao" has a long medicinal history and has a variety of pharmacological activities. As the main resource of "zicao" in Tibet, Onosma glomeratum Y. L. Liu (tuan hua dian zi cao), usually used for treating pneumonia in Tibet, has not been reported deeply. In order to determine the main anti-inflammatory active ingredients of Onosma glomeratum Y. L. Liu, in this study, the extracts enriched in naphthoquinones and polysaccharides were optimized prepared form Onosma glomeratum Y. L. Liu by ultrasonic extraction, and reflux extraction, respectively, with Box-Behnken design effect surface method. And their anti-inflammatory abilities were screened on LPS induced A549 cells model, for figuring out the anti-inflammatory active ingredients from Onosma glomeratum Y. L. Liu.The extract enriched naphthoquinone was obtained under following condition: extract with 85% ethanol in a liquid to material ratio of 1:40 g/mL at 30 °C for 30 minutes using ultrasound, leading to the extraction rate of total naphthoquinone as 0.98 ± 0.017%; the extract enriched polysaccharides was prepared as follows: extract 82 minutes at 100 °C with distilled water in a liquid to material ratio of 1:50 g/mL, with extraction rate of polysaccharide as 7.07 ± 0.02%.On the LPS-induced A549 cell model, the polysaccharide extract from Onosma glomeratum Y. L. Liu showed better anti-inflammatory effects than the naphthoquinone extract, indicating the extract enriched in polysaccharides is the anti-inflammatory extract of Onosma glomeratum Y. L. Liu, which could serve as a potential anti-inflammatory extract in medical and food industries in the future.


Asunto(s)
Boraginaceae , Naftoquinonas , Lipopolisacáridos , Antiinflamatorios/farmacología , Polisacáridos/farmacología
6.
Water Sci Technol ; 89(7): 1630-1646, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38619894

RESUMEN

Due to the colloidal stability, the high compressibility and the high hydration of extracellular polymeric substances (EPS), it is difficult to efficiently dehydrate sludge. In order to enhance sludge dewatering, the process of ultrasonic (US) cracking, chitosan (CTS) re-flocculation and sludge-based biochar (SBB) skeleton adsorption of water-holding substances to regulate sludge dewaterability was proposed. Based on the response surface method, the prediction model of the specific resistance to filtration (SRF) and sludge cake moisture content (MC) was established. The US cracking time and the dosage of CTS and SBB were optimized. The results showed that the optimal parameters of the three were 5.08 s, 10.1 mg/g dry solids (DS) and 0.477 g/g DS, respectively. Meantime, the SRF and MC were 5.4125 × 1011 m/kg and 76.8123%, which significantly improved the sludge dewaterability. According to the variance analysis, it is found that the fitting degree of SRF and MC model is good, which also confirms that there is significant interaction and synergy between US, CTS and SBB, and the contribution of CTS and SBB is greater. Moreover, the process significantly improves the sludge's calorific value and makes its combustion more durable.


Asunto(s)
Quitosano , Aguas del Alcantarillado , Ultrasonido , Carbón Orgánico , Filtración , Agua , Eliminación de Residuos Líquidos/métodos
7.
World J Microbiol Biotechnol ; 40(10): 312, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39198372

RESUMEN

Microbes within a consortium exhibit a synergistic interaction, enhancing their collective capacity to perform functions more effectively than a single species, especially in the degradation of keratin-rich substrates. To achieve a more stable and efficient breakdown of chicken feathers, a comprehensive screening of over 9,000 microbial strains was undertaken. This meticulous selection process identified strains with the capability to degrade keratin effectively. Subsequently, antagonistic tests were conducted to isolate strains of fungi and bacteria that were non-antagonistic, which were then used to form the artificial microbial consortia. The optimal fermentation conditions for the keratinophilic microbial consortia were determined through the optimization of response surface methodology. The results revealed that 11 microbial strains-comprising of 4 fungi and 7 bacteria-were particularly proficient in degrading chicken feathers. The artificially constructed microbial consortia (AMC) comprised two bacterial strains and one fungal strain. The optimal conditions for feathers degradation were identified as a 10 g/L concentration of chicken feathers, a 2.6% microbial inoculation volume and a fermentation fluid pH of 9. Under these conditions, the degradation rate for chicken feathers reached a significant 74.02%, representing an 11.45% increase over the pre-optimization rate. The AMC developed in this study demonstrates the potential for efficient and economical process of livestock and poultry feathers. It provides innovative insights and a theoretical foundation for tackling the challenging degradation of keratin-rich materials. Furthermore, this research lays the groundwork for the separation and purification of keratins, as well as the development of novel proteases, which could have profound implications for a range of applications.


Asunto(s)
Bacterias , Pollos , Plumas , Fermentación , Hongos , Queratinas , Consorcios Microbianos , Plumas/microbiología , Plumas/metabolismo , Animales , Pollos/microbiología , Queratinas/metabolismo , Hongos/metabolismo , Hongos/clasificación , Hongos/aislamiento & purificación , Hongos/genética , Bacterias/metabolismo , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Concentración de Iones de Hidrógeno , Biodegradación Ambiental
8.
Exp Eye Res ; 235: 109629, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37625574

RESUMEN

Chrysanthemum tea is commonly consumed by Chinese consumers mainly due to the Chrysanthemum flower being a potential source of antioxidants. The current study investigates the effects of extraction time and temperature on Chrysanthemum flower aqueous extract (CFAE) antioxidant capacity, including Trolox equivalent antioxidant capacity (TEAC), ferrous iron-chelating activity, and superoxide radical scavenging capacity (SRSC) using a two-factor, three-level factorial design of the response surface method (RSM). The TEAC and SRSC of CFAE are higher at higher temperatures and longer times up to a certain point, and the highest TEAC and SRSC are achieved at a 100 °C extraction temperature for 45 min. The fructose induced-αA-crystallin (Cry) glycation model system was used to evaluate the effects of the CFAE on anti-glycoxidation activities. The antioxidant ingredients obtained from CFAE significantly impede the production of advanced glycation end products from protein glycoxidation products (dityrosine, kynurenine, and N'-methylkynurenine) in the glycation process of αA-Cry and exhibit strong anti-glycating activity. The glycation inhibitory effects of CFAE are concentration-dependent. C. indicum L. exhibits greater potential for preventing cataracts compared to C. morifolium Ramat CFAE's antioxidant and anti-glycation properties suggest its potential application as a natural ingredient in the development of agents to combat glycation.


Asunto(s)
Chrysanthemum , Cristalinas , Humanos , Antioxidantes/farmacología , Extractos Vegetales/farmacología , Flores
9.
J Appl Microbiol ; 134(2)2023 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-36639125

RESUMEN

AIM: This study investigates the individual and combined effects of fermentation parameters for improving cell biomass productivity and the resistance to freezing, freeze-drying, and freeze-dried storage of Lactobacillus delbrueckii subsp. bulgaricus CFL1. METHODS AND RESULTS: Cells were cultivated at different temperatures (42°C and 37°C) and pH values (5.8 and 4.8) and harvested at various growth phases (mid-exponential, deceleration, and stationary growth phases). Specific acidifying activity was determined after fermentation, freezing, freeze-drying, and freeze-dried storage. Multiple regression analyses were performed to identify the effects of fermentation parameters on the specific acidifying activity losses and to generate the corresponding 3D response surfaces. A multiobjective decision approach was applied to optimize biomass productivity and specific acidifying activity. The temperature positively influenced biomass productivity, whereas low pH during growth reduced the loss of specific acidifying activity after freezing and freeze-drying. Furthermore, freeze-drying resistance was favored by increased harvest time. CONCLUSIONS: Productivity, and freezing and freeze-drying resistances of L. delbrueckii subsp. bulgaricus CFL1 were differentially affected by the fermentation parameters studied. There was no single fermentation condition that improved both productivity and resistance to freezing and freeze-drying. Thus, Pareto fronts were helpful to optimize productivity and resistance, when cells were grown at 42°C, pH 4.8, and harvested at the deceleration phase.


Asunto(s)
Lactobacillus delbrueckii , Congelación , Lactobacillus delbrueckii/metabolismo , Fermentación , Liofilización/métodos , Temperatura
10.
Bioorg Chem ; 131: 106333, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36587504

RESUMEN

Hesperidin (C28H34O15), a flavanone glycoside abundantly present in citrus fruits, has proven therapeutic effects including anti-inflammatory activities. Herein, we report a novel formulation of HESP loaded solid lipid nanoparticles (SLNs) using hot homogenization and ultrasound to improve the poor solubility and bioavailability. In the present study, the formulation was developed and optimized by response surface method and then characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy (FT-IR), and dynamic light scattering (DLS). Encapsulation efficiency was determined and the anti-inflammatory effect was assessed through in vivo ear edema inflammation model. According to the electron microscopy results, the product has a spherical shape. The optimized parameters produced small size (179.8 ± 3.6 nm) HESP-SLNs with high encapsulation efficiency (93.0 ± 3.8 %). The outcomes exhibited that encapsulation in SLNs carriers improves the anti-inflammatory potential of HESP.


Asunto(s)
Antiinflamatorios , Hesperidina , Nanopartículas , Vehículos Farmacéuticos , Antiinflamatorios/administración & dosificación , Portadores de Fármacos/química , Hesperidina/administración & dosificación , Lípidos/química , Nanopartículas/química , Espectroscopía Infrarroja por Transformada de Fourier , Vehículos Farmacéuticos/química
11.
Environ Res ; 237(Pt 1): 116803, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37532214

RESUMEN

Sea squirts, a tunicate, are found in all oceans and can foul marine ports and aquaculture, mainly affecting shipping and biodiversity. In this study, cellulose was extracted from sea squirts, and its hydrophilic properties were improved by substituting the hydrogen ions of the cellulose -OH with dopamine. The modified cellulose was used to prepare a hydrogel for use as a dust-fixing agent (CDP) to reduce air pollution caused by dust. After response surface method optimization, the proportions of binder, water-retaining agent, wetting agent, and antifreeze in CDP were 0.97, 1.44, 0.23, and 6.32%, respectively. This composition improved the wetting ability and permeability of CDP on particle surfaces. CDP exhibited good water retention at -11-50 °C. CDP reduced the wind erosion rate of dust at a wind speed of 12 m/s to 1.18%. The molecular dynamics method was used to analyze the wetting process and mechanism of CDP, revealing that hydrogen bonds were the dominant force at the solid-liquid interface. The adsorption of CDP onto the surface of coal increased the number of hydrophilic points. Water molecules were adsorbed on these hydrophilic points through hydrogen bonding, improving the binding energy between the solid and liquid interfaces. The application of ascidian cellulose in dust control makes full use of the biological value of ascidians, promoting sustainable development of the global biological economy.

12.
Environ Res ; 221: 115246, 2023 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-36657595

RESUMEN

Resource utilization of gangue solid waste has become an essential research direction for green development. This study prepared a novel gangue based geopolymer adsorbent (GPA) for the removal of Cd(II) from wastewater using pretreatment gangue (PG) as the main raw material. The ANOVA indicated that the obtained quadratic model of fitness function (R2 > 0.99, P-value <0.0001) was significant and adequate, and the contribution of the three preparation conditions to the removal of Cd(II) was: calcination temperature > Na2CO3:PG ratio > water-glass solid content. The hybrid response surface method and gray wolf optimization (RSM-GWO) algorithm were adopted to acquire the optimum conditions: Na2CO3:PG ratio = 1.05, calcination temperature of 701 °C, solid content of water glass of 22.42%, and the removal efficiency of Cd(II) by GPA obtained under the optimized conditions (GPAC) was 97.84%. Adsorption kinetics, adsorption isotherms and characterization by XRD, FTIR, Zeta potential, FSEM-EDS and BET were utilized to investigate the adsorption mechanism of GPAC on Cd(II). The results showed that the adsorption of Cd(II) from GPAC was consistent with the pseudo-second-order model (R2 = 0.9936) and the Langmuir model (R2 = 0.9988), the adsorption was a monolayer adsorption process and the computed maximum Cd(II) adsorption (50.76 mg g-1) was approximate to experimental results (51.47 mg g-1). Moreover, the surface morphology of GPAC was rough and porous with a specific surface area (SSA) of 18.54 m2 g-1, which provided abundant active sites, and the internal kaolinite was destroyed to produce a zeolite-like structure where surface complexation and ion exchange with Cd(II) through hydroxyl (-OH) and oxygen-containing groups (-SiOH and -AlOH) were the main adsorption mechanisms. Thus, GPAC is a lucrative adsorbent material for effective Cd(II) wastewater treatment, complying with the "high value-added" usage of solid wastes and "waste to cure poison" green sustainable development direction.


Asunto(s)
Aguas Residuales , Contaminantes Químicos del Agua , Cadmio , Contaminantes Químicos del Agua/análisis , Temperatura , Caolín , Adsorción , Cinética , Concentración de Iones de Hidrógeno
13.
Environ Res ; 227: 115640, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-36933636

RESUMEN

Currently, the pharmaceutical and personal care products (PPCPs) have posed great challenge to advanced oxidation techniques (AOTs). In this study, we decorated sponge iron (s-Fe0) with Cu and Pd (s-Fe0-Cu-Pd) and further optimized the synthesis parameters with a response surface method (RSM) to rapidly degrade diclofenac sodium (DCF). Under the RSM-optimized conditions of Fe: Cu: Pd = 100: 4.23: 0.10, initial solution pH of 5.13, and input dosage of 38.8 g/L, 99% removal of DCF could be obtained after 60 min of reaction. Moreover, the morphological structure of trimetal was characterized with high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), X-ray diffraction (XRD), X-ray photoelectron spectra (XPS). Electron spin resonance (ESR) signals have also been applied to capture reactive hydrogen atoms (H*), superoxygen anions, hydroxyl radicals, and single state oxygen (1O2). Furthermore, the variations of DCF and its selective degradation products over a series of s-Fe0-based bi(tri)metals have been compared. Additionally, the degradation mechanism of DCF has also been explored. To our best knowledge, this is the first report revealing the selective dechlorination of DCF with low toxicity over Pd-Cu co-doped s-Fe0 trimetal.


Asunto(s)
Hierro , Contaminantes Químicos del Agua , Hierro/química , Diclofenaco/química , Aniones , Oxidación-Reducción , Contaminantes Químicos del Agua/análisis
14.
Chem Biodivers ; 20(3): e202200776, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36652073

RESUMEN

Hippophae rhamnoides L. polysaccharide was optimized with flash extraction by response surface design. The optimum process conditions were: rotation rate 5000 r/min, extraction time 15 s, extraction temperature 90 °C and liquid-to-material ratio 38 mL/g, the extraction yield was 15.28±0.02 %. HRP-1 and HRP-2 obtained by 40 % and 60 % graded alcohol precipitation were characterized. The results indicated that HRP-1 and HRP-2 both composed of mannose, ribose, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose, xylose, arabinose with different molar ratio and the molecular weights were 380.59 kDa and 288.24 kDa, respectively. In addition, the in vitro antioxidant and immunoenhancement activities of HRP-1 and HRP-2 were analyzed, and the two fractions showed good free radical scavenging activity against ⋅OH, ABTS⋅+ , DPPH⋅, and extremely strong immunomodulatory activity against RAW264.7 cells. Indicating that flash extraction is suitable for extraction of HRP, the structural study of HRP provides a scientific theoretical basis for the development of Hippophae rhamnoides.


Asunto(s)
Hippophae , Antioxidantes/farmacología , Antioxidantes/química , Polisacáridos/farmacología , Polisacáridos/química , Galactosa
15.
Sensors (Basel) ; 23(9)2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37177481

RESUMEN

As the Internet of Things (IOT) becomes more widely used in our everyday lives, an increasing number of wireless communication devices are required, meaning that an increasing number of signals are transmitted and received through antennas. Thus, the performance of antennas plays an important role in IOT applications, and increasing the efficiency of antenna design has become a crucial topic. Antenna designers have often optimized antennas by using an EM simulation tool. Although this method is feasible, a great deal of time is often spent on designing the antenna. To improve the efficiency of antenna optimization, this paper proposes a design of experiments (DOE) method for antenna optimization. The antenna length and area in each direction were the experimental parameters, and the response variables were antenna gain and return loss. Response surface methodology was used to obtain optimal parameters for the layout of the antenna. Finally, we utilized antenna simulation software to verify the optimal parameters for antenna optimization, showing how the DOE method can increase the efficiency of antenna optimization. The antenna optimized by DOE was implemented, and its measured results show that the antenna gain and return loss were 2.65 dBi and 11.2 dB, respectively.

16.
Sensors (Basel) ; 23(12)2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37420792

RESUMEN

Tungsten heavy alloys (WHAs) are an extremely hard-to-machine material extensively used in demanding applications such as missile liners, aerospace, and optical molds. However, the machining of WHAs remains a challenging task as a result of their high density and elastic stiffness which lead to the deterioration of the machined surface roughness. This paper proposes a brand-new multi-objective dung beetle algorithm. It does not take the cutting parameters (i.e., cutting speed, feed rate, and depth of cut) as the optimization objects but directly optimizes cutting forces and vibration signals monitored using a multi-sensor (i.e., dynamometer and accelerometer). The cutting parameters in the WHA turning process are analyzed through the use of the response surface method (RSM) and the improved dung beetle optimization algorithm. Experimental verification shows that the algorithm has better convergence speed and optimization ability compared with similar algorithms. The optimized forces and vibration are reduced by 9.7% and 46.47%, respectively, and the surface roughness Ra of the machined surface is reduced by 18.2%. The proposed modeling and optimization algorithms are anticipated to be powerful to provide the basis for the parameter optimization in the cutting of WHAs.


Asunto(s)
Escarabajos , Tungsteno , Animales , Algoritmos , Aleaciones , Heces
17.
Molecules ; 28(5)2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36903566

RESUMEN

A batch of Fe-modified biochars MS (for soybean straw), MR (for rape straw), and MP (for peanut shell) were prepared by impregnating biochars pyrolyzed from three different raw biomass materials, i.e., peanut shell, soybean straw, and rape straw, with FeCl3 solution in different Fe/C impregnation ratios (0, 0.112, 0.224, 0.448, 0.560, 0.672, and 0.896) in this research. Their characteristics (pH, porosities, surface morphologies, crystal structures, and interfacial chemical behaviors) and phosphate adsorption capacities and mechanisms were evaluated. The optimization of their phosphate removal efficiency (Y%) was analyzed using the response surface method. Our results indicated that MR, MP, and MS showed their best phosphate adsorption capacity at Fe/C ratios of 0.672, 0.672, and 0.560, respectively. Rapid phosphate removal was observed within the first few minutes and the equilibrium was attained by 12 h in all treatment. The optimal conditions for phosphorus removal were pH = 7.0, initial phosphate concentration = 132.64 mg L-1, and ambient temperature = 25 °C, where the Y% values were 97.76, 90.23, and 86.23% of MS, MP, and MR, respectively. Among the three biochars, the maximum phosphate removal efficiency determined was 97.80%. The phosphate adsorption process of three modified biochars followed a pseudo-second-order adsorption kinetic model, indicating monolayer adsorption based on electrostatic adsorption or ion exchange. Thus, this study clarified the mechanism of phosphate adsorption by three Fe-modified biochar composites, which present as low-cost soil conditioners for rapid and sustainable phosphate removal.


Asunto(s)
Fosfatos , Contaminantes Químicos del Agua , Adsorción , Carbón Orgánico/química , Fósforo , Contaminantes Químicos del Agua/química
18.
Prep Biochem Biotechnol ; 53(8): 923-930, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36576214

RESUMEN

Onosma hookeri Clarke. var. longiforum Duthie (OHC-LD), one of the traditional Tibetan medicine, has been found many functions, including removing heat to cool blood, nourishing lung and inhibiting bacteria. In order to study the polysaccharides in OHC-LD water extract, the optimal extraction progress of polysaccharides of the roots of OHC-LD by response surface method designed with three-factor three-level Box-Behnken method and the antioxidant capacity and immune activity of the crude polysaccharide were studied in this investigation. Under the best conditions, the extraction yield of polysaccharide was 3.19±0.09% (n = 3). After purification, the crude polysaccharide was obtained with polysaccharide contents of 42.57%, which demonstrated stronger DPPH scavenging activity than BHT at low concentrations (<625 µg/mL), and comparable ABTS radical scavenging activity as BHT at high concentrations (≥1250 µg/mL). Additionally, it also exhibited a certain cell proliferation activity and an enhancement of the phagocytic ability of RAW264.7 cells. This study revealed that the crude polysaccharide from the roots of OHC-LD might be exploited as a natural antioxidant and immune enhance agent in the future in both medical and food industry.


Asunto(s)
Antioxidantes , Agua , Antioxidantes/química , Polisacáridos/química , Raíces de Plantas
19.
Molecules ; 28(24)2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38138612

RESUMEN

Here, we aimed to optimize the ethanol extraction technology for Yujin powder (YJP) and evaluate its safety. The ultrasonic-assisted ethanol reflux extraction method refluxing was used to extract YJP. The parameters were optimized through a combination of single-factor and response surface methodology (RSM). The comprehensive Y value score calculated using the content of 13 active ingredients in YJP ethanolic extracts (YEEs) and the yield of the dry extract were used as measuring criteria. RSM with a Box-Behnken design using three factors and three levels was adopted to optimize the ethanol extraction technology for YJP. Finally, acute and subchronic toxicity tests were performed to evaluate its safety. The results revealed the best technological parameters: a liquid-material ratio of 24:1, an ethanol concentration of 69%, assistance of ultrasound (40 °C, 50 kHZ, 30 min), reflux time of 53 min, and reflux temperature of 50 °C. In acute toxicity tests, the maximum administration dosage in mice was 28.21 g/kg, which is higher than 10 times the clinical dosage. Adverse effects in the acute and subchronic toxicity tests were not observed. All clinical indexes were normal. In conclusion, the RSM based on AHP-CRITIC weight analysis could be used to optimize the ethanol extraction technology for YJP and YEEs prepared under the above conditions and ensure high safety.


Asunto(s)
Medicamentos Herbarios Chinos , Etanol , Ratones , Animales , Proceso de Jerarquía Analítica , Medicamentos Herbarios Chinos/toxicidad , Temperatura , Extractos Vegetales
20.
Artículo en Inglés | MEDLINE | ID: mdl-38146218

RESUMEN

Moringa oleifera utilization in water treatment to eliminate emerging pollutants such as heavy metal ions, pesticides, pharmaceuticals, and pigments has been extensively evaluated. The efficacy of Moringa oleifera biosorbent has been investigated in diverse research work using various techniques, including its adsorption capacity kinetic, thermodynamic evaluation, adsorbent modifications, and mechanism behind the adsorption process. The Langmuir isotherm provided the most remarkable experimental data fit for batch adsorption investigations, whereas the best fit was obtained with the pseudo-second order kinetic model. Furthermore, only a few papers that combined batch adsorption with fixed-bed column investigations were examined. In the latter articles, the scientists modified the adsorbent to increase the material's adsorption capacity as determined by analytical methods, including IR spectroscopy, scanning electronic microscope (SEM), and X-ray diffraction (XRD). However, the raw material can show appreciable adsorption capacity values, proving moringa's potency as a biosorbent. Hydrogen bonds, electrostatic interaction, and van der Waals forces were the main processes in the found and reported adsorbent-adsorbate interactions. These mechanisms could change depending on the physiochemical nature of adsorption. Although frequently employed for heavy metal ions and dye adsorption, Moringa oleifera can still be explored in pesticide and medication adsorption investigations due to the few publications in this comprehensive review. This study, therefore, examined different Adsorbents from the Moringa oleifera plant, as well as parameters and models for enhancing the adsorption process.


Asunto(s)
Metales Pesados , Moringa oleifera , Plaguicidas , Contaminantes Químicos del Agua , Moringa oleifera/química , Contaminantes Químicos del Agua/química , Redes Neurales de la Computación , Adsorción , Cinética , Termodinámica , Iones , Concentración de Iones de Hidrógeno
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