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Optimization of Preparation of Oregano Oil Microspheres by Box-Behnken Response Surface Methodology
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作者 Fei HAN Mengyao TU +5 位作者 Hui YANG Hekun DUAN Fuhao HU Xinli LIANG Yang GUAN Wei XU 《Medicinal Plant》 2024年第4期40-45,共6页
[Objectives]To optimize the formulation and preparation of oregano oil microspheres by Box-Behnken response surface methodology.[Methods]Chitosan was used as the carrier material to prepare oregano oil microspheres by... [Objectives]To optimize the formulation and preparation of oregano oil microspheres by Box-Behnken response surface methodology.[Methods]Chitosan was used as the carrier material to prepare oregano oil microspheres by emulsion crosslinking method.The encapsulation efficiency,drug loading and ID 50 were used as the evaluation indicators,and the comprehensive score(OD)obtained by"coefficient of variation-AHP comprehensive weighting method"was used as the final evaluation indicator.The formulation design and preparation process were optimized by single factor experiment and Box-Behnken response surface methodology,and the optimal process parameters were determined.[Results]The optimal formulation and preparation process parameters of oregano oil microspheres were as follows:the ratio of oregano oil to chitosan was 2∶1,the emulsifying speed of double emulsion was 200 r/min,the amount of emulsifier in the colostrum was 4%,and the volume of curing agent was 1.0 mL.The average encapsulation efficiency was 45.33%±1.32%,the average drug loading was 30.59%±2.45%,and the median diameter(ID 50)was 52.596μm±0.023%.[Conclusions]The encapsulation efficiency,drug loading and ID 50 of oregano oil chitosan microspheres prepared by emulsion crosslinking method met the requirements.The drug-loaded microsphere not only can be used as a preparation finished product for direct application,but also be used as a product intermediate to lay a foundation for the research and development of subsequent dosage forms. 展开更多
关键词 Oregano oil CHITOSAN MICROSPHERES PREPARATION response surface methodology(RSM)
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The Influence of Tartaric Acid in the Silver Nanoparticle Synthesis Using Response Surface Methodology
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作者 Yatim Lailun Ni’mah Afaf Baktir +1 位作者 Dewi Santosaningsih Suprapto Suprapto 《Journal of Renewable Materials》 EI CAS 2024年第2期245-258,共14页
Silver nanoparticles(AgNPs)synthesized using tartaric acid as a capping agent have a great impact on the reaction kinetics and contribute significantly to the stability of AgNPs.The protective layer formed by tartaric... Silver nanoparticles(AgNPs)synthesized using tartaric acid as a capping agent have a great impact on the reaction kinetics and contribute significantly to the stability of AgNPs.The protective layer formed by tartaric acid is an important factor that protects the silver surface and reduces potential cytotoxicity problems.These attributes are critical for assessing the compatibility of AgNPs with biological systems and making them suitable for drug delivery applications.The aim of this research is to conduct a comprehensive study of the effect of tartaric acid concentration,sonication time and temperature on the formation of silver nanoparticles.Using Response Surface Methodology(RSM)with Face-Centered Central Composite Design(FCCD),the optimization process identifies the most favorable synthesis conditions.UV-Vis spectrum regression analysis shows that AgNPs stabilized with tartaric acid are more stable than AgNPs without tartaric acid.This highlights the increased stability that tartaric acid provides in AgNP ssssynthesis.Particle size distribution analysis showed a multimodal distribution for AgNPs with tartaric acid and showed the smallest size peak with an average size of 20.53 nm.The second peak with increasing intensity shows a dominant average size of 108.8 nm accompanied by one standard deviation of 4.225 nm and a zeta potential of−11.08 mV.In contrast,AgNPs synthesized with polyvinylpyrrolidone(PVP)showed a unimodal particle distribution with an average particle size of 81.62 nm and a zeta potential of−2.96 mV.The more negative zeta potential of AgNP-tartaric acid indicates its increased stability.Evaluation of antibacterial activity showed that AgNPs stabilized with tartaric acid showed better performance against E.coli and B.subtilis bacteria compared with AgNPs-PVP.In summary,this study highlights the potential of tartaric acid in AgNP synthesis and suggests an avenue for the development of stable AgNPs with versatile applications. 展开更多
关键词 Tartaric acid silver nanoparticle polyvinyl pyrrolidone response surface methodology
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Optimizing Bucket Elevator Performance through a Blend of Discrete Element Method, Response Surface Methodology, and Firefly Algorithm Approaches
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作者 Pirapat Arunyanart Nithitorn Kongkaew Supattarachai Sudsawat 《Computers, Materials & Continua》 SCIE EI 2024年第8期3379-3403,共25页
This research introduces a novel approach to enhancing bucket elevator design and operation through the integration of discrete element method(DEM)simulation,design of experiments(DOE),and metaheuristic optimization a... This research introduces a novel approach to enhancing bucket elevator design and operation through the integration of discrete element method(DEM)simulation,design of experiments(DOE),and metaheuristic optimization algorithms.Specifically,the study employs the firefly algorithm(FA),a metaheuristic optimization technique,to optimize bucket elevator parameters for maximizing transport mass and mass flow rate discharge of granular materials under specified working conditions.The experimental methodology involves several key steps:screening experiments to identify significant factors affecting bucket elevator operation,central composite design(CCD)experiments to further explore these factors,and response surface methodology(RSM)to create predictive models for transport mass and mass flow rate discharge.The FA algorithm is then applied to optimize these models,and the results are validated through simulation and empirical experiments.The study validates the optimized parameters through simulation and empirical experiments,comparing results with DEM simulation.The outcomes demonstrate the effectiveness of the FA algorithm in identifying optimal bucket parameters,showcasing less than 10%and 15%deviation for transport mass and mass flow rate discharge,respectively,between predicted and actual values.Overall,this research provides insights into the critical factors influencing bucket elevator operation and offers a systematic methodology for optimizing bucket parameters,contributing to more efficient material handling in various industrial applications. 展开更多
关键词 Discrete element method(DEM) design of experiments(DOE) firefly algorithm(FA) response surface methodology(RSM)
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Optimization and Characterization of Cellulose Extraction from Grevillea robusta (Silky Oak) Leaves by Soda-Anthraquinone Pulping Using Response Surface Methodology
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作者 Catherine N. Muya John M. Onyari +2 位作者 Lydia W. Njenga Joab O. Onyango Wilson M. Gitari 《Green and Sustainable Chemistry》 2024年第3期43-65,共23页
Response surface methodology (RSM) using the central composite design (CCD) was applied to examine the impact of soda-anthraquinone pulping conditions on Grevillea robusta fall leaves. The pulping factors studied were... Response surface methodology (RSM) using the central composite design (CCD) was applied to examine the impact of soda-anthraquinone pulping conditions on Grevillea robusta fall leaves. The pulping factors studied were: NaOH charge 5% to 20% w/v, pulping time 30 to 180 minutes, and the anthraquinone charge 0.1 to 0.5% w/w based on the oven-dried leaves. The responses evaluated were the pulp yield, cellulose content, and the degree of delignification. Various regression models were used to evaluate the effects of varying the pulping conditions. The optimum conditions attained were;NaOH charge of 14.63%, 0.1% anthraquinone, and a pulping period of 154 minutes, corresponding to 20.68% pulp yield, 80.56% cellulose content, and 70.34% lignin removal. Analysis of variance (ANOVA), was used to determine the most important variables that improve the extraction process of cellulose. The experiment outcomes matched those predicted by the model (Predicted R2 = 0.9980, Adjusted R2 = 0.9994), demonstrating the adequacy of the model used. FTIR analysis confirmed the elimination of the non-cellulosic fiber constituents. The lignin and hemicellulose-related bands (around 1514 cm−1, 1604 cm−1, 1239 cm−1, and 1734 cm−1) decreased with chemical treatment, indicating effective cellulose extraction by the soda-anthraquinone method. Similar results were obtained by XRD, SEM and thermogravimetric analysis of the extracted cellulose. Therefore, Grevillea robusta fall leaves are suitable renewable, cost-effective, and environmentally friendly non-wood biomass for cellulose extraction. 展开更多
关键词 Cellulose Extraction response surface methodology Central Composite Design DELIGNIFICATION
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Optimization of Methylene Blue Dye Adsorption onto Coconut Husk Cellulose Using Response Surface Methodology: Adsorption Kinetics, Isotherms and Reusability Studies
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作者 Frank Ouru Omwoyo Geoffrey Otieno 《Journal of Materials Science and Chemical Engineering》 2024年第2期1-18,共18页
In this study, coconut husk cellulose was employed as a cost-effective and environmentally friendly adsorbent to eliminate methylene blue (MB) dye from aqueous solutions. The successful development of response surface... In this study, coconut husk cellulose was employed as a cost-effective and environmentally friendly adsorbent to eliminate methylene blue (MB) dye from aqueous solutions. The successful development of response surface methodology paired with a central composite design (RSM-CCD) enabled the optimization and modelling of the adsorption process. The study investigated the individual and combined effects of three variables (pH, contact time, and initial MB dye concentration) on the adsorption of MB dye onto coconut husk cellulose. The developed RSM-CCD model exhibited a remarkable degree of precision in predicting the removal efficiency of MB dye within the specified experimental parameters. This was demonstrated by the strong regression parameters, with an R<sup>2</sup> value of 99.79% and an adjusted R<sup>2</sup> value of 99.6%. The study depicted that the optimal parameters for attaining a 98.8827% removal of MB dye using coconut husk cellulose were as follows: an initial MB dye concentration of 30 mg∙L<sup>−1</sup>, contact time of 120 minutes, and pH 7 at a fixed adsorbent dose of 0.5 g. The Freundlich isotherm model provided the most satisfactory description of the equilibrium adsorption isotherms, suggesting that MB dye adsorption onto coconut husk cellulose occurs on a heterogeneous surface. The experimental results demonstrated a strong agreement with the pseudo-second-order kinetics model, indicating that the number of active sites present on the cellulose adsorbent predominantly influences the adsorption process of MB dye. Additionally, the adsorbent made from coconut husk cellulose exhibited the potential to be reused, as it retained its efficiency for a maximum of three cycles of adsorption of MB dye. The results of this study show that coconut husk cellulose has the potential to be an effective and sustainable adsorbent for removing MB dye from aqueous solutions. 展开更多
关键词 Adsorption Kinetics Isotherms OPTIMIZATION response surface methodology CELLULOSE
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Optimization of Cellulose Nanocrystal Isolation from Ayous Sawdust Using Response Surface Methodology
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作者 Tchigo Alifa Hamida Aminatou +1 位作者 Oumar Said Jean-Bosco Tchatchueng 《Journal of Materials Science and Chemical Engineering》 2024年第1期36-55,共20页
This study focuses on the extraction of cellulose nanocrystals (CNC), from microcrystalline cellulose (MCC), derived from Ayous sawdust. The process involves multiple steps and a large amount of chemical products. The... This study focuses on the extraction of cellulose nanocrystals (CNC), from microcrystalline cellulose (MCC), derived from Ayous sawdust. The process involves multiple steps and a large amount of chemical products. The objective of this research was to determine the effects of factors that impact the isolation process and to identify the optimal conditions for CNC isolation by using the response surface methodology. The factors that varied during the process were the quantity of MCC, the concentration of sulfuric acid, the hydrolysis time and temperature, and the ultrasonic treatment time. The response measured was the yield. The study found that with 5.80 g of microcrystalline cellulose, a sulfuric acid concentration of 63.50% (w/w), a hydrolysis time of 53 minutes, a hydrolysis temperature of 69˚C, and a sonication time of 19 minutes are the ideal conditions for isolation. The experimental yield achieved was (37.84 ± 0.99) %. The main factors influencing the process were the sulfuric acid concentration, hydrolysis time and temperature, with a significant influence (p < 0.05). Infrared characterization results showed that nanocrystals were indeed isolated. With a crystallinity of 35.23 and 79.74, respectively, for Ayous wood fiber and nanocrystalline cellulose were observed by X-ray diffraction, with the formation of type II cellulose, thermodynamically more stable than native cellulose type I. 展开更多
关键词 Ayous Sawdust Lignocellulosic Waste ISOLATION Cellulose Nanocrystals OPTIMIZATION response surface methodology
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Effects of main ecological factors on the growth of marine green alga Caulerpa sertularioides using the response surface methodology
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作者 Bingxin Huang Yue Chu +2 位作者 Rongjuan Wang Yixiao Wang Lanping Ding 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第11期90-97,共8页
Caulerpa sertularioides is an invasive potential blooming green alga in China but it remains poorly studied.We studied the effects of ecological factors on its growth.Optimum conditions of ecological factors,i.e.,irra... Caulerpa sertularioides is an invasive potential blooming green alga in China but it remains poorly studied.We studied the effects of ecological factors on its growth.Optimum conditions of ecological factors,i.e.,irradiance,temperature,and salinity,for the growth of its fragments were determined in the response surface methodology(RSM).The specific growth rates(SGR)of the fragments were determined in single-factor experiment.The results show that the SGR of C.sertularioides peaked under the conditions of irradiance 37.5μmol/(m~2·s),temperature25℃,and salinity 30.Meanwhile,using the Box-Behnken design,the conditions were further optimized and verified to be:irradiance 39.03μmol/(m~2·s),temperature 25.29℃,and salinity 30.06,under which the SGR reached 4.66%.The results provide new theoretical data and solutions for the cultivation,invasion prediction,and monitoring of Caulerpa species in China and the world.The RSM method may have great potential applications in the environmental adaptation characteristics of new macroalgal cultivars,intensive orientation cultured germplasm,and environmental hazard analysis of cultivated species in the field. 展开更多
关键词 Caulerpa sertularioides FRAGMENT response surface methodology(RSM) ecological factor
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Optimization of Mortar Compressive Strength Prepared with Waste Glass Aggregate and Coir Fiber Addition Using Response Surface Methodology
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作者 Cut Rahmawati Lia Handayani +6 位作者 Muhtadin Muhammad Faisal Muhammad Zardi S.M.Sapuan Agung Efriyo Hadi Jawad Ahmad Haytham F.Isleem 《Journal of Renewable Materials》 EI 2023年第10期3751-3767,共17页
Waste Glass(WGs)and Coir Fiber(CF)are not widely utilized,even though their silica and cellulose content can be used to create construction materials.This study aimed to optimize mortar compressive strength using Resp... Waste Glass(WGs)and Coir Fiber(CF)are not widely utilized,even though their silica and cellulose content can be used to create construction materials.This study aimed to optimize mortar compressive strength using Response Surface Methodology(RSM).The Central Composite Design(CCD)was applied to determine the optimization of WGs and CF addition to the mortar compressive strength.Compressive strength and microstructure testing with Scanning Electron Microscope(SEM),Fourier-transform Infrared Spectroscopy(FT-IR),and X-Ray Diffraction(XRD)were conducted to specify the mechanical ability and bonding between the matrix,CF,and WGs.The results showed that the chemical treatment of CF produced 49.15%cellulose,with an average particle size of 1521μm.The regression of a second-order polynomial model yielded an optimum composition consisting of 12.776%WGs and 2.344%CF with a predicted compressive strength of 19.1023 MPa.C-S-H gels were identified in the mortars due to the dissolving of SiO_(2) in WGs and cement.The silica from WGs increased the C-S-H phase.CF plays a role in preventing,bridging,and branching micro-cracks before reaching maximum stress.WGs aggregates and chemically treated CF are suitable to be composited in mortar to increase compressive strength. 展开更多
关键词 CELLULOSE response surface methodology waste glass coir fiber composite
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Response Surface Methodology-Based SERS for Determination of Gymnodimine
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作者 Siyang Chan Yaoyi Wu +2 位作者 Yifan Liu Donghang Yin Fei Wang 《American Journal of Analytical Chemistry》 2023年第8期305-325,共21页
Gymnodimine (GYM), a fast-acting marine toxin, is destructive to aquaculture and human health through contaminated shellfish. The current detection methods in GYM have definite drawbacks in operation, such as the dema... Gymnodimine (GYM), a fast-acting marine toxin, is destructive to aquaculture and human health through contaminated shellfish. The current detection methods in GYM have definite drawbacks in operation, such as the demand for delicate instruments and the consumption of time. Therefore, silver colloid was utilized as a surface-enhanced Raman scattering (SERS) desirable substrate for sensitive and rapid detection of GYM in lake and shellfish samples. The theoretical spectrum of GYM is calculated by density functional theory (DFT), and the substrate performance is evaluated by a rhodamine 6 G probe. Under the optimal SERS experimental condition calculated by the response surface methodology, the low limit of detection of 0.105 μM with R<sup>2</sup> of 0.9873 and a broad linearity range of 0.1 - 10 μM was achieved for GYM detection. In addition, the substrate was satisfyingly applied to detect gymnodimine in the lake and shellfish matrix samples with LOD as low as 0.148 μM and 0.170 μM, respectively. These results demonstrated a promising SERS platform for detecting marine toxins in seafood for food safety and pharmaceutical research. 展开更多
关键词 surface-Enhanced Raman Scattering Gymnodimine Ag Colloid box-behnken Design response surface methodology
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Response Surface Methodology as an Approach for Optimization of Vinegar Fermentation Conditions Using Three Different Thermotolerant Acetic Acid Bacteria
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作者 Mariama Ciré Kourouma Malick Mbengue +1 位作者 Abdoulaye Thioye Coumba Touré Kane 《Food and Nutrition Sciences》 2023年第7期638-656,共19页
This study aimed to investigate optimal fermentation conditions of biological acetic acid fermentation for vinegar production. Optimization was performed on 3 acetic acid bacteria strains namely VMA1, VMA7 and VMAO us... This study aimed to investigate optimal fermentation conditions of biological acetic acid fermentation for vinegar production. Optimization was performed on 3 acetic acid bacteria strains namely VMA1, VMA7 and VMAO using Response Surface Methodology (RSM). A Box-Behnken-Design (BBD) was achieved with three different independent process parameters involving: fermentation temperature, original alcohol concentration and original acetic acid concentration and one dependent variable (acetic acid yield). The results showed that the mathematical models describe correctly the relationship between responses and factors (F values of the models (p R<sup>2</sup> (coefficient of correlation) respectively 0.96, 0.94, 0.98, and adjusted R<sup>2</sup> 0.95, 0.92, 0.98). The maximum acidity was obtained respectively at fermentation temperatures, original alcohol concentrations and original acetic acid concentrations ranging from [37.5°C - 45°C], [16% - 20% (v/v)], [1.5% - 2% (w/v)] for VMA1, [40°C - 45°C], [14.5% - 20% (v/v)], [1.7% - 2% (w/v)] for VMA7 and [42°C - 45°C], [17% - 20% (v/v)], [1.5% - 2% (w/v)] for VMAO. The use of these acetic strains in the production of vinegar may seriously lead to a decrease or even an ablation of the costs related to the cooling of bioreactors especially in warm and hot countries, in the context of global warming. 展开更多
关键词 VINEGAR response surface methodology box-behnken-Design OPTIMIZATION
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Optimization of Preparation Conditions of Modified Oyster Shell Powder/Ce-N-TiO2 by Response Surface Methodology (RSM)
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作者 Wei Zhang Qizheng You +3 位作者 Jinkai Shu Aihe Wang Hai Lin Xuchao Yan 《Journal of Environmental Protection》 CAS 2023年第1期16-31,共16页
A new composite photocatalyst of modified oyster shell powder/Ce-N-TiO<sub>2</sub> was prepared by sol-gel method. Based on single factor experiment, Ce doping rate, N doping rate and calcination temperatu... A new composite photocatalyst of modified oyster shell powder/Ce-N-TiO<sub>2</sub> was prepared by sol-gel method. Based on single factor experiment, Ce doping rate, N doping rate and calcination temperature were taken as input variables. Based on the central composite design (BBD) response surface model, two functional relationship models between three independent variables and glyphosate removal rate were established to evaluate the influence degree of independent variables and interaction on catalyst. The significance of the model and regression coefficient was tested by variance analysis. The analysis of the obtained data showed that the degradation performance of the composite photocatalyst was significantly affected by the calcination temperature and the rate of N doping, while the rate of Ce doping had little effect;at the calcination temperature of 505.440°C, the degradation rate of glyphosate reached the maximum of 82.15% under the preparation conditions of 17.057 mol% N doping and 0.165 mol% Ce doping, respectively. 展开更多
关键词 Modified Titanium Dioxide response surface methodology (RSM) PHOTOCATALYSIS GLYPHOSATE
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Optimization for Microbial Degumming of Ramie with Bacillus subtilis DZ_(5) in Submerged Fermentation by Orthogonal Array Design and Response Surface Methodology
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作者 刘芬 陈杨栋 +2 位作者 朱鹏 曹张军 张兴群 《Journal of Donghua University(English Edition)》 CAS 2023年第5期475-481,共7页
As a kind of natural fiber,ramie fiber has distinctive advantages in textile application,but the application is limited due to the traditional degumming mode.Compared with the traditional degumming process,the microbi... As a kind of natural fiber,ramie fiber has distinctive advantages in textile application,but the application is limited due to the traditional degumming mode.Compared with the traditional degumming process,the microbial degumming process has many advantages.To obtain the optimal conditions for degumming ramie with Bacillus subtilis DZ_(5)(BS DZ_(5)),a combined statistical approach of orthogonal array design(OAD)and response surface methodology(RSM)was used.The influences of initial pH of the bacteria medium,culture temperature,shaking speed,degumming time and inoculum size on submerged fermentation degumming were evaluated by using fractional factorial design.The main factors in the analysis were culture temperature,shaking speed and initial pH.The residual gum mass fraction was used as the optimization index,and the optimal conditions for degumming were determined by central composite design and RSM.Thus with only a limited number of experiments,an optimal ramie microbial degumming condition was found as the culture temperature of 40℃,the initial pH in the culture medium of 8.5,the shaking speed of 205 r/min,the degumming time of 96 h and the inoculum size of 5%.After microbial degumming of ramie under the optimal conditions,there was only 10.6%residual gum by mass in the fiber.In addition,the effective degumming of BS DZ_(5)was also confirmed by a scanning electron microscope(SEM). 展开更多
关键词 microbial degumming OPTIMIZATION RAMIE orthogonal array design(OAD) response surface methodology(RSM)
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Optimization of Solid-state Fermentation Conditions of Sophora japonica cv.jinhuai by Response Surface Methodology
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作者 Miao YANG Chaohao GU +5 位作者 Qiling LI Zhiqiang HUANG Hao LIU Yanxi LAI Zongyou CHEN Kaimei ZHU 《Medicinal Plant》 CAS 2023年第5期36-41,共6页
[Objectives]To optimize the solid-state fermentation process of Flos Sophorae Immaturus by Penicillium with Sophora japonica cv.jinhuai as raw material.[Methods]The fermentation conditions were optimized by single fac... [Objectives]To optimize the solid-state fermentation process of Flos Sophorae Immaturus by Penicillium with Sophora japonica cv.jinhuai as raw material.[Methods]The fermentation conditions were optimized by single factor experiment and response surface methodology with quercetin content as the dependent variable.[Results]According to the established model,the optimal fermentation process of Flos Sophorae Immaturus was obtained as follows:temperature 29.97℃,time 6.88 d,rotation speed 180.86 rpm,inoculation amount 3.93 mL,and the expected content of quercetin was 34.8053 mg/g.Based on this,the fermentation parameters were adjusted,and the actual content was 33.67 mg/g,which was close to the predicted value.[Conclusions]The optimization of fermentation process of Flos Sophorae Immaturus by response surface methodology provides a reference for the development and utilization of this medicinal material. 展开更多
关键词 Sophora japonica cv.Jinhuai QUERCETIN PENICILLIUM Fermentation process response surface methodology(RSM)
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Catalytic Hydrothermal Liquefaction of Water Hyacinth Using Fe3O4/NiO Nanocomposite: Optimization of Reaction Conditions by Response Surface Methodology
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作者 Godwin Aturagaba Dan Egesa +1 位作者 Edward Mubiru Emmanuel Tebandeke 《Journal of Sustainable Bioenergy Systems》 2023年第3期73-98,共26页
This research aimed at optimizing the reaction conditions for the catalytic hydrothermal liquefaction (HTL) of water hyacinth using iron oxide/nickel oxide nanocomposite as catalysts. The iron oxide/nickel oxide nanoc... This research aimed at optimizing the reaction conditions for the catalytic hydrothermal liquefaction (HTL) of water hyacinth using iron oxide/nickel oxide nanocomposite as catalysts. The iron oxide/nickel oxide nanocomposite was synthesized by the co-precipitation method and used in the hydrothermal liquefaction of water hyacinth. The composition and structural morphology of the synthesized catalysts were determined using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atomic absorption spectroscopy (AAS). The particle size distribution of the catalyst nanoparticles was determined by the Image J software. Three reaction parameters were optimized using the response surface methodology (RSM). These were: temperature, residence time, and catalyst dosage. A maximum bio-oil yield of 59.4 wt% was obtained using iron oxide/nickel oxide nanocomposite compared to 50.7 wt% obtained in absence of the catalyst. The maximum bio-oil yield was obtained at a temperature of 320°C, 1.5 g of catalyst dosage, and 60 min of residence time. The composition of bio-oil was analyzed using gas chromatography-mass spectroscopy (GC-MS) and elemental analysis. The GC-MS results showed an increase of hydrocarbons from 58.3% for uncatalyzed hydrothermal liquefaction to 88.66% using iron oxide/nickel oxide nanocomposite. Elemental analysis results revealed an increase in the hydrogen and carbon content and a reduction in the Nitrogen, Oxygen, and Sulphur content of the bio-oil during catalytic HTL compared to HTL in absence of catalyst nanoparticles. The high heating value increased from 33.5 MJ/Kg for uncatalyzed hydrothermal liquefaction to 38.6 MJ/Kg during the catalytic HTL. The catalyst nanoparticles were recovered from the solid residue by sonication and magnetic separation and recycled. The recycled catalyst nanoparticles were still efficient as hydrothermal liquefaction (HTL) catalysts and were recycled four times. The application of iron oxide/ nickel oxide nanocomposites in the HTL of water hyacinth increases the yield of bio-oil and improves its quality by reducing hetero atoms thus increasing its energy performance as fuel. Iron oxide/nickel oxide nanocomposites used in this study are widely available and can be easily recovered magnetically and recycled. This will potentially lead to an economical, environmentally friendly, and sustainable way of converting biomass into biofuel. 展开更多
关键词 Catalytic Hydrothermal Liquefaction Water Hyacinth BIO-OIL Central Com-posite Design response surface methodology OPTIMIZATION
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Optimization of preparing V_2O_5 by calcination from ammonium metavanadate using response surface methodology 被引量:6
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作者 刘秉国 彭金辉 +3 位作者 万润东 张利波 郭胜惠 张世敏 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第3期673-678,共6页
Parameters of technique to prepare vanadium pentoxide by calcination from ammonium metavanadate were optimized using central composite design of response surface methodology. A quadratic equation model for decompositi... Parameters of technique to prepare vanadium pentoxide by calcination from ammonium metavanadate were optimized using central composite design of response surface methodology. A quadratic equation model for decomposition rate was built and effects of main factors and their corresponding relationships were obtained. The results of the statistical analysis show that the decomposition rate of ammonium metavanadate is significantly affected by calcination temperature and calcination time. The optimized calcination conditions are as follows: calcination temperature 669.71 K, calcination time 35.9 min and sample mass 4.25 g. The decomposition rate of ammonium metavanadate is 99.71%,which coincides well with experimental value of 99.27% under the optimized conditions, suggesting that regressive equation fits the decomposition rates perfectly. XRD reveals that it is feasible to prepare the V2O5 by calcination from ammonium metavanadate using response surface methodology. 展开更多
关键词 vanadium pentoxide ammonium metavanadate CALCINATION response surface methodology
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Adsorption property of direct fast black onto acid-thermal modified sepiolite and optimization of adsorption conditions using Box-Behnken response surface methodology 被引量:2
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作者 Chengyuan SU Weiguang LI Yong WANG 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2013年第4期503-511,共9页
The adsorption of direct fast black onto acid- thermal modified sepiolite was investigated. Batch adsorp- tion experiments were performed to evaluate the influences of experimental parameters such as initial dye conce... The adsorption of direct fast black onto acid- thermal modified sepiolite was investigated. Batch adsorp- tion experiments were performed to evaluate the influences of experimental parameters such as initial dye concentra- tion, initial solution pH and adsorbent dosage on the adsorption process. The three-factor and three-level Box- Behnken response surface methodology (RSM) was utilized for modeling and optimization of the adsorption conditions for direct fast black onto the acid-thermal modified sepiolite. The raw sepiolite was converted to acid-thermal modified sepiolite, and changes in the fourier transform infrared spectrum (FTIR) adsorption bands of the sample were noted at 3435 cm] and 1427 cm1. The zeolitic water disappeared and the purity of sepiolite was improved by acid-thermal modification. The decoloriza- tion rate of direct fast black adsorbed increased from 68.2% to 98.9% on acid-thermal modified sepiolite as the initial solution pH decreased from 10 to 2. When the adsorbent dosage reached to 2.5 g. L-1, 2.0 g. L-~, 1.5 g. I,I and 1.0g.L-1, the decolorization rate was 90.3%, 86.7%, 61.0% and 29.8%, respectively. When initial dye concen- tration increased from 25 to 200 rag. L-l, the decolorization rate decreased from 91.9% to 60.0%. The RSM results showed that the interaction between adsorbent dosage and pH to be a significant factor. The optimum conditions were as follows: the adsorbent dosage 1.99 g.L-1, pH 4.22, and reaction time 5.2 h. Under these conditions, the decolor- ization rate was 95.1%. The three dimensional fluores- cence spectra of direct fast black before and after treatment showed that the direct fast black was almost all adsorbed by the acid-thermal modified sepiolite. 展开更多
关键词 direct fast black acid-thermal modified sepio-lite ADSORPTION response surface methodology
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Identification of processing window for extrusion of large thick-walled Inconel 625 alloy pipes using response surface methodology 被引量:5
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作者 郭良刚 党利 +2 位作者 杨合 张君 郑文达 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第7期1902-1911,共10页
Identifying suitable processing window is necessary but difficult for achieving favorable microstructure and performance in extrusion of large thick-walled pipe with difficult-to-deform Inconel 625 alloy. In this work... Identifying suitable processing window is necessary but difficult for achieving favorable microstructure and performance in extrusion of large thick-walled pipe with difficult-to-deform Inconel 625 alloy. In this work, a method was established for identifying the extrusion process window considering temperature control using response surface methodology. Firstly, the response surface models, which correlate temperature rise and peak temperature to key extrusion parameters, have been developed by orthogonal regression based on finite element calculated data. Secondly, the coupled effects of the key extrusion parameters on the temperature rise and peak temperature have been disclosed based on the regression models. Lastly, suitable extrusion processing windows, which are described by contour map of peak temperature in the space of extrusion speed and initial billet temperature, have been established for different extrusion ratios. Using the identified process window, a suitable combination of the key extrusion parameters can be determined conveniently and quickly. 展开更多
关键词 profile extrusion processing window response surface methodology difficult-to-deform materials finite element simulation
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SCRAMJET INLET MULTI-OBJECTIVE OPTIMIZATION BASED ON RESPONSE SURFACE METHODOLOGY 被引量:1
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作者 李健 谷良贤 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第3期205-210,共6页
The uniform design and response surface methodology (RSM) are applied to the multi-objective optimization of a 2-D mixed compression scramjet inlet. The set of experimental design points on the design space is selec... The uniform design and response surface methodology (RSM) are applied to the multi-objective optimization of a 2-D mixed compression scramjet inlet. The set of experimental design points on the design space is selected by the uniform design, and the inlet performance is analyzed by computational fluid dynamics (CFD). Then complete quadratic polynomial response surface approximation models are constructed based on the performance analysis results and then used to replace theoriginal complex inlet performance model. The optimization is conducted using a multi-objective genetic algorithm NSGA-Ⅱ, and the Pareto optimal solution set is obtained. Results show that the uniform design and RSM can reduce the computational complexity of numerical simulation and improve the optimization efficiency. 展开更多
关键词 scramjet inlet response surface methodology oblique shock multi-objective optimization
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Device Robust-Design by Using Response Surface Methodology
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作者 谢晓锋 鲁勇 +1 位作者 张文俊 杨之廉 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第8期817-824,共8页
Device robust-design is inherently a multiple-objective optimization problem.Using design of experiments (DoE) combined with response surface methodology (RSM) can satisfy the great incentive to reduce the number of t... Device robust-design is inherently a multiple-objective optimization problem.Using design of experiments (DoE) combined with response surface methodology (RSM) can satisfy the great incentive to reduce the number of technology CAD(TCAD) simulations that need to be performed.However,the errors of RSM models might be large enough to diminish the validity of the results for some nonlinear problems.To find the feasible design space,a new method with objectives-oriented design in generations that takes the errors of RSM model into account is presented.After the augment design of experiments in promising space according to the results of RSM model in current generation,the feasible space will be emerging as the model errors deceasing.The results on FIBMOS examples show that the methodology is efficient. 展开更多
关键词 response surface methodology design of experiments device robust-design
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Optimization of the Fermentation Conditions of Sweet Oats by Response Surface Methodology
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作者 张泓 黄艳杰 +1 位作者 黄志兵 许杨 《Agricultural Science & Technology》 CAS 2014年第3期483-487,498,共6页
Objective] The purpose of this study was to evaluate the effects of five variables (steaming time, moisture content before inoculation, inoculation amount, fer-mentation temperature, fermentation time) on the sweetn... Objective] The purpose of this study was to evaluate the effects of five variables (steaming time, moisture content before inoculation, inoculation amount, fer-mentation temperature, fermentation time) on the sweetness of sweet oats, obtained the best fermentation conditions. [Method] Plackett-Burman (PB) was to evaluate the effects of five variables, and selected significant factors. The steepest ascent was used to approach the optimal response surface experimental area. The optimal fer-mentation condition was obtained by central composite design and response surface analysis. [Results] It was indicated that moisture content, inoculation amount and fer-mentation temperature had significant influences on the content of the reducing sugars. The optimal conditions of moisture content, inoculation amount and temper-ature were 45.26%, 0.014%(g/g) and 28 ℃, respectively. The predicted value of the reducing sugar content was 13.16 mg/g. [Conclusion] Under the optimal conditions, the content of the reducing sugars in the sweet oats could be up to 12.91 mg/g, which was on the whole consistent with the predictive maximum value. 展开更多
关键词 Sweet oats FERMENTATION Reducing sugars response surface methodology
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