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A systematic scoping review of study methodology for randomized controlled trials investigating probiotics in athletic and physically active populations
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作者 Alex E.Mohr David B.Pyne +2 位作者 Geovana Silva Fogaça Leite Deborah Akins Jamie Pugh 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期61-71,共11页
Background:The purported ergogenic and health effects of probiotics have been a topic of great intrigue among researchers,practitioners,and the lay public alike.There has also been an increased research focus within t... Background:The purported ergogenic and health effects of probiotics have been a topic of great intrigue among researchers,practitioners,and the lay public alike.There has also been an increased research focus within the realm of sports science and exercise medicine on the athletic gut microbiota.However,compared to other ergogenic aids and dietary supplements,probiotics present unique study challenges.The objectives of this systematic scoping review were to identify and characterize study methodologies of randomized controlled trials investigating supplementation with probiotics in athletes and physically active individuals.Methods:Four databases(MEDLINE,CINAHL,Cochrane CENTRAL,and Cochrane Database of Systematic Reviews)were searched for randomized controlled studies involving healthy athletes or physically active individuals.An intervention with probiotics and inclusion of a control and/or placebo group were essential.Only peer-reviewed articles in English were considered,and there were no date restrictions.Results were extracted and presented in tabular form to detail study protocols,characteristics,and outcomes.Bias in randomized controlled trials was determined with the RoB 2.0 tool.Results:A total of 45 studies were included in the review,with 35 using a parallel group design and 10 using a cross-over design.Approximately half the studies used a single probiotic and the other half a multi-strain preparation.The probiotic dose ranged from 2×10^(8)to 1×10^(11)colony forming units daily,and the length of intervention was between 7 and 150 days.Fewer than half the studies directly assessed gastrointestinal symptoms,gut permeability,or the gut microbiota.The sex ratio of participants was heavily weighted toward males,and only 3 studies exclusively investigated females.Low-level adverse events were reported in only 2 studies,although the methodology of reporting varied widely.The risk of bias was generally low,although details on randomization were lacking in some studies.Conclusion:There is a substantial body of research on the effects of prob iotic supplementation in healthy athletes and physically active individuals.Considerable heterogeneity in probiotic selection and dosage as well as outcome measures has made clinical and mechanistic interpretation challenging for both health care practitioners and researchers.Attention to issues of randomization of participants,treatments and interventions,selection of outcomes,demographics,and reporting of adverse events will facilitate more trustworthy interpretation of probiotic study results and inform evidence-based guidelines. 展开更多
关键词 EXERCISE Experimental methodology Gastrointestinal symptoms Gut microbiota Probiotic supplementation
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An operator methodology for the global dynamic analysis of stochastic nonlinear systems
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作者 Kaio C.B.Benedetti Paulo B.Goncalves +1 位作者 Stefano Lenci Giuseppe Rega 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2023年第3期164-169,共6页
In a global dynamic analysis,the coexisting attractors and their basins are the main tools to understand the system behavior and safety.However,both basins and attractors can be drastically influenced by uncertainties... In a global dynamic analysis,the coexisting attractors and their basins are the main tools to understand the system behavior and safety.However,both basins and attractors can be drastically influenced by uncertainties.The aim of this work is to illustrate a methodology for the global dynamic analysis of nondeterministic dynamical systems with competing attractors.Accordingly,analytical and numerical tools for calculation of nondeterministic global structures,namely attractors and basins,are proposed.First,based on the definition of the Perron-Frobenius,Koopman and Foias linear operators,a global dynamic description through phase-space operators is presented for both deterministic and nondeterministic cases.In this context,the stochastic basins of attraction and attractors’distributions replace the usual basin and attractor concepts.Then,numerical implementation of these concepts is accomplished via an adaptative phase-space discretization strategy based on the classical Ulam method.Sample results of the methodology are presented for a canonical dynamical system. 展开更多
关键词 Stochastic dynamics Global nonlinear dynamics Coexisting attractors Operator methodology Adaptative discretization Noise
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Enhancing wood efficiency through comprehensive wood flow analysis:Methodology and strategic insights
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作者 Ruisheng Wang Peer Haller 《Forest Ecosystems》 SCIE CSCD 2024年第2期172-183,共12页
Wood,an essential natural resource in human civilization,remains widely used despite advances in technology and material substitution.The surge in greenhouse gas emissions and environmental concerns accentuates the ne... Wood,an essential natural resource in human civilization,remains widely used despite advances in technology and material substitution.The surge in greenhouse gas emissions and environmental concerns accentuates the need for optimizing wood utilization.Material flow analysis is a powerful tool for tracking material flows and stocks,aiding resource management and environmental decision-making.However,the full extent of its methodological dimensions,particularly within the context of the wood supply chain,remains relatively unexplored.In this study,we delve into the existing literature on wood flow analysis,discussing its primary objectives,materials involved,temporal and spatial scales,data sources,units,and conversion factors.Additionally,data uncertainty,data reconciliation and crucial assumptions in material flow analysis are highlighted in this paper.Key findings reveal the significance of wood cascading and substitution effects by replacing non-wood materials,where they can reduce greenhouse gas emissions more than the natural carbon sink of forests and wood products.The immediate impact of short-term wood cascading might not be as robust as the substitution effect,with energy substitution showcasing better results than material substitution.However,it's crucial to note that these conclusions could experience significant reversal from a long-term and global perspective.Strategies for improving wood efficiency involve maximizing material use,advancing construction technologies,extending product lifespans,promoting cascade use,and optimizing energy recovery processes.The study underscores the need for standardized approaches in wood flow analysis and emphasizes the potential of wood efficiency strategies in addressing environmental challenges. 展开更多
关键词 Material flow analysis WOOD methodology Cascade use Substitution effects
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Research on the development methodology for clinical practice guidelines for organic integration of traditional Chinese medicine and Western medicine
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作者 Ying-Hui Jin Yan-Ping Wang +22 位作者 Ying-Lan Xie Gui-Hua Tian Xiao-Yu Zhang Nan-Nan Shi Ke-Hu Yang Xin Sun Yao-Long Chen Da-Rong Wu Xin-Feng Guo Long Ge Chen Zhao Cheng Lu Yin Jiang Jing Guo Si-Yu Yan Yong-Bo Wang Qiao Huang Xiang-Ying Ren Ying-Yue Rao Yun-Yun Wang Meng-Qian Yuan Xian-Tao Zeng Hong-Cai Shang 《Military Medical Research》 SCIE CAS CSCD 2024年第3期313-322,共10页
Integrated traditional Chinese medicine(TCM)and Western medicine(WM)is a new medical science grounded in the knowledge bases of both TCM and WM,which then forms a unique modern medical system in China.Integrated TCM a... Integrated traditional Chinese medicine(TCM)and Western medicine(WM)is a new medical science grounded in the knowledge bases of both TCM and WM,which then forms a unique modern medical system in China.Integrated TCM and WM has a long history in China,and has made important achievements in the process of clinical diagnosis and treatment.However,the methodological defects in currently published clinical practice guidelines(CPGs)limit its development.The organic integration of TCM and WM is a deeper integration of TCM and WM.To realize the progression of"integration"to"organic integration",a targeted and standardized guideline development methodology is needed.Therefore,the purpose of this study is to establish a standardized development procedure for clinical practice guidelines for the organic integration of TCM and WM to promote the systematic integration of TCM and WM research results into clinical practice guidelines in order to achieve optimal results as the whole is greater than the sum of the parts. 展开更多
关键词 methodology Traditional Chinese medicine Western medicine Organic integration Clinical practice guidelines(CPGs)
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Pearls of meta-analyses and systematic review in scientific evidence
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作者 Sunny Chi Lik Au 《World Journal of Clinical Cases》 SCIE 2024年第16期2701-2703,共3页
Scientific evidence develops bit by bit from case reports,case series;to larger casecontrol,case-cohort;and further escalate to randomized controlled trials.This echoed the importance of continue publishing World jour... Scientific evidence develops bit by bit from case reports,case series;to larger casecontrol,case-cohort;and further escalate to randomized controlled trials.This echoed the importance of continue publishing World journal of Clinical Cases,where novel and advancing discoveries start from a single case.In contrast,at the other end of the realm of evidence synthesis,systematic review and meta-analysis represent distinct yet interconnected processes.Butorphanol in epidural labor analgesia has long been studied since 1989,and with 70 publications from MEDLINE searches.However,there was no meta-analysis,nor any systematic review published so far.The latest in-press article published by Tang et al.on the protocol for the systematic review and meta-analysis on the safety and effectiveness of butorphanol in epidural labor analgesia is encouraging.We believe the findings of this study will be valuable for clinical practice as well as for future research. 展开更多
关键词 META-ANALYSIS systematic review methodology RESEARCH JOURNAL ACADEMIC
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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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Bidirectional link between periodontitis and systemic inflammation in diabetic retinopathy
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作者 Prateek Nishant Sony Sinha +1 位作者 Ranjeet Kumar Sinha Arvind Kumar Morya 《World Journal of Diabetes》 SCIE 2024年第7期1651-1653,共3页
Periodontitis is independently associated with numerous lifestyle diseases.Diabetic patients have approximately threefold increased odds of periodontitis,which in turn increases the risk of systemic inflammation.The s... Periodontitis is independently associated with numerous lifestyle diseases.Diabetic patients have approximately threefold increased odds of periodontitis,which in turn increases the risk of systemic inflammation.The study by Thazhe Poyil et al is an effort to establish the inflammatory link between diabetic retinopathy(DR)and periodontitis based on the periodontal inflamed surface area in diabetic patients with and without DR.To further advance the study,we suggest refining the eligibility criteria to explicitly state the clinical correlates of periodontitis and DR,larger sample size and improved sampling methodology,matching of baseline characteristics of the two groups,as well as improved statistical approach and interpretation of the study findings.Measurement of hemoglobin A1c(HbA1c)in studies comparing type 2 diabetes mellitus patients with DR of matched severity with and without periodontitis could provide a clearer picture of whether HbA1c level is indeed influenced by periodontitis. 展开更多
关键词 Glucose intolerance HYPERGLYCEMIA INFLAMMATION Research methodology VISION
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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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Ingredients-based Methodology and Fuzzy Logic Combined Short-Duration Heavy Rainfall Short-Range Forecasting:An Improved Scheme
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作者 TIAN Fu-you XIA Kun +2 位作者 SUN Jian-hua ZHENG Yong-guang HUA Shan 《Journal of Tropical Meteorology》 SCIE 2024年第3期241-256,共16页
Short-duration heavy rainfall(SHR),as delineated by the National Meteorological Center of the China Me-teorological Administration,is characterized by hourly rainfall amounts no less than 20.0 mm.SHR is one of the mos... Short-duration heavy rainfall(SHR),as delineated by the National Meteorological Center of the China Me-teorological Administration,is characterized by hourly rainfall amounts no less than 20.0 mm.SHR is one of the most common convective weather phenomena that can cause severe damage.Short-range forecasting of SHR is an important part of operational severe weather prediction.In the present study,an improved objective SHR forecasting scheme was developed by adopting the ingredients-based methodology and using the fuzzy logic approach.The 1.0°×1.0°National Centers for Environmental Prediction(NCEP)final analysis data and the ordinary rainfall(0.1-19.9 mm h-1)and SHR observational data from 411 stations were used in the improved scheme.The best lifted index,the total precipitable water,the 925 hPa specific humidity(Q 925),and the 925 hPa divergence(DIV 925)were selected as predictors based on objective analysis.Continuously distributed membership functions of predictors were obtained based on relative frequency analysis.The weights of predictors were also objectively determined.Experiments with a typhoon SHR case and a spring SHR case show that the main possible areas could be captured by the improved scheme.Verification of SHR forecasts within 96 hours with NCEP global forecasts 1.0°×1.0°data initiated at 08:00 Beijing Time during the warm seasons in 2015 show the results were improved from both deterministic and probabilistic perspectives.This study provides an objectively feasible choice for short-range guidance forecasts of SHR.The scheme can be applied to other convective phenomena. 展开更多
关键词 ingredients-based methodology fuzzy logic approach probability of short-duration heavy rainfall(SHR) improved forecasting scheme objectively obtained membership functions
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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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Simulated patient methodology as a“gold standard”in community pharmacy practice:Response to criticism
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作者 Christian Kunow Bernhard Langer 《World Journal of Methodology》 2024年第2期172-174,共3页
The simulated patient methodology(SPM)is considered the“gold standard”as covert participatory observation.SPM is attracting increasing interest for the investigation of community pharmacy practice;however,there is c... The simulated patient methodology(SPM)is considered the“gold standard”as covert participatory observation.SPM is attracting increasing interest for the investigation of community pharmacy practice;however,there is criticism that SPM can only show a small picture of everyday pharmacy practice and therefore has limited external validity.On the one hand,a certain design and application of the SPM goes hand in hand with an increase in external validity.Even if,on the other hand,this occurs at the expense of internal validity due to the trade-off situation,the justified criticism of the SPM for investigating community pharmacy practice can be countered. 展开更多
关键词 Simulated patient methodology Community pharmacy Gold standard Covert participatory observation Internal validity External validity
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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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A New Discipline of Science-The Study of Open Complex Giant System and Its Methodology 被引量:34
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作者 Qian XuesenChina Association for Science and Technology, Beijing 100863, ChinaYu JingyuanBeijing Institute of Information and Control, P.O.Box 824, Beijing 100037, ChinaDai RuweiInstitute of Automation, Chinese Academy of Sciences, Beijing 100080, China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1993年第2期2-12,共11页
This paper introduces the conception of open complex giant system and the methodology for dealing with the system, with stress on its profound significance in development of science and technology. The authors conclud... This paper introduces the conception of open complex giant system and the methodology for dealing with the system, with stress on its profound significance in development of science and technology. The authors conclude that the reductionism underlying the exact science is not suitable to open complex giant system, and the only feasible alternative is the meta-synthetic engineering from the qualitative to the quantitative. 展开更多
关键词 systems science methodology Meta-synthetic engineering.
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A"One Engine with Six Gears"System Engineering Methodology for the Economic Development of Unconventional Oil and Gas in China 被引量:7
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作者 Guoxin Li Chenggang Xian He Liu 《Engineering》 SCIE EI CAS 2022年第11期105-115,共11页
Unconventional oil and gas resources have become the most important and realistic field for increasing China’s domestic oil and gas reserves and production.At present,the production scale does not match the massive a... Unconventional oil and gas resources have become the most important and realistic field for increasing China’s domestic oil and gas reserves and production.At present,the production scale does not match the massive amount of resources and the rapid growth of proven geological reserves.The challenges of technology,cost,management,and methodology restrict large-scale and economic development.Based on successful practices,a"one engine with six gears"system engineering methodology is put forward,which includes life-cycle management,overall synergy,interdisciplinary cross-service integration,marketoriented operation,socialized support,digitalized management,and low-carbon and green development.The methodology has been proved to be effective in multiple unconventional oil and gas national demonstration areas,including the Jimusar continental shale oil demonstration area.Disruptive views are introduced-namely,that unconventional oil and gas do not necessarily yield a low return,nor do they necessarily have a low recovery factor.A determination to achieve economic benefit must be a pervasive underlying goal for managers and experts.Return and recovery factors,as primary focuses,must be adhered to during China’s development of unconventional oil and gas.The required methodology transformation includes a revolution in management systems to significantly decrease cost and increase production,resulting in technological innovation. 展开更多
关键词 Unconventional oil and gas resources system engineering methodology transformation Life-cycle management Geoscience-to-engineering integration
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Reliability Analysis on Repairable System with Dual Input Closed-Loop Feedback Link Considering Shutdown Correlation Based on Goal Oriented Methodology 被引量:3
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作者 伊枭剑 石坚 +3 位作者 穆慧娜 张瑶 郭少伟 梁启海 《Journal of Donghua University(English Edition)》 EI CAS 2016年第2期314-318,共5页
Goal oriented( GO) methodology is a kind of success oriented system reliability analysis method and has been used widely.The repairable system with dual input closed-loop feedback link( DICLFL) considering shutdown co... Goal oriented( GO) methodology is a kind of success oriented system reliability analysis method and has been used widely.The repairable system with dual input closed-loop feedback link( DICLFL) considering shutdown correlation didn't make reliability analysis accurately based on existing GO methodology. So, a reliability analysis method used to deal with DICLFL considering shutdown correlation is provided based on GO methodology.Firstly, a new operator, which is used to describe DICLFL considering shutdown correlation,whose number is 1,is created and named as Type 9C operator. And then,the formulas of type 9C operator are derived based on Markov process theory. Finally,the new method presented in this paper is adopted to conduct the reliability analysis of an electro-hydraulic servo speed control system. The analysis result is compared with those of Monte Carlo simulation and fault tree analysis( FTA). The comparison results show that this new reliability analysis method based on GO methodology is feasible and meaningful for reliability analysis of repairable systems with DICLFL considering shutdown correlation.Meantime,it will be useful for more other applications. 展开更多
关键词 shutdown correlation goal oriented(GO) methodology GO operator dual input closed-loop feedback link(DICLFL) reliability analysis
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A Mooring System Deployment Design Methodology for Vessels at Varying Water Depths 被引量:2
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作者 XU Sheng-wen LIANG Ming-xiao +1 位作者 WANG Xue-feng DING Ai-bing 《China Ocean Engineering》 SCIE EI CSCD 2020年第2期185-197,共13页
In this paper,a methodology for designing mooring system deployment for vessels at varying water depths is proposed.The Non-dominated Sorting Genetic Algorithm-II(NSGA-II)is combined with a self-dependently developed ... In this paper,a methodology for designing mooring system deployment for vessels at varying water depths is proposed.The Non-dominated Sorting Genetic Algorithm-II(NSGA-II)is combined with a self-dependently developed vessel-mooring coupled program to find the optimal mooring system deployment considering both station-keeping requirements and the safety of the mooring system.Two case studies are presented to demonstrate the methodology by designing the mooring system deployments for a very large floating structure(VLFS)module and a semi-submersible platform respectively at three different water depths.It can be concluded from the obtained results that the mooring system can achieve a better station-keeping ability with relatively shorter mooring line when deployed in the shallow water.The safety factor of mooring line is mainly dominated by the maximum instantaneous tension increment in the shallow water,while the pre-tension has a decisive influence on the safety factor of the mooring line in the deep water. 展开更多
关键词 mooring system deployment design methodology NSGA-II varying water depths
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Reliability Analysis of Hydraulic Transmission Oil Supply System of Power-Shift Steering Transmission with GO Methodology 被引量:3
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作者 伊枭剑 董海平 +2 位作者 姜基平 赖岳华 张忠 《Journal of Donghua University(English Edition)》 EI CAS 2014年第6期785-788,共4页
GO methodology is a success-oriented method for system reliability analysis. There are components with multi-fault modes in repairable systems. It is a problem to use the existing GO method to make reliability analysi... GO methodology is a success-oriented method for system reliability analysis. There are components with multi-fault modes in repairable systems. It is a problem to use the existing GO method to make reliability analysis of such repairable systems. A new GO method for reliability analysis of such repairable systems with multifault modes was presented. Firstly, calculation equations of reliability parameters of operators which were used to describe components with multi-fault modes in reparable systems were derived based on Markov process theory. Then, this new GO method was applied in reliability analysis of a hydraulic transmission oil supply system( HTOSS) of a power-shift steering transmission at low and high speeds. Finally,Compared with fault tree analysis( FTA) and Monte Carlo simulation,the results show that this new GO method is correct and suitable for reliability analysis of repairable system with multi-fault modes. 展开更多
关键词 multi-fault modes GO methodology reliability analysis hydraulic transmission oil supply system(HTOSS) of power-shift steering transmission
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The optimization of phenolic compounds extraction from cactus pear(Opuntia ficus-indica) skin in a reflux system using response surface methodology 被引量:1
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作者 Aguirre Joya Jorge De La Garza Toledo Heliodoro +2 位作者 Zugasti Cruz Alejandro Belmares Cerda Ruth Aguilar Cristóbal No 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第6期436-442,共7页
Objective:To extract,quantify,and evaluate the phenolic content in Opuntia ficus-indica skin for their antioxidant capacity with three different methods(ABTS,DPPH,and lipid oxidation)and to optimize the extraction con... Objective:To extract,quantify,and evaluate the phenolic content in Opuntia ficus-indica skin for their antioxidant capacity with three different methods(ABTS,DPPH,and lipid oxidation)and to optimize the extraction conditions[time,temperature and ethanol concentration)in a reflux system.Methods:The extraction process was done using a reflux system.A San CristobalⅡexperimental design with three variables and three levels was used.The variables evaluated were time of extraction(h),concentration of ethanol(%,v/v)and temperature(°C).The extraction process was optimized using a response surface methodology.Results:It was observed that at higher temperature more phenolic compounds were extracted,but the antioxidant capacity was decreased.The optimum conditions for phenolic compounds extraction and antioxidant capacity mixing the three methods were as Follows:45%of ethanol,80℃and 2 hours of extraction.Values obtained in our results are little higher that other previously reported.Conclusions:It can he concluded the by-products of Opuntia ficus-indica represent a good source of natural antioxidants with possible applications in food,cosmetics or drugs industries. 展开更多
关键词 OPUNTIA ficus-indica REFLUX Phenolics ANTIOXIDANTS Prickly PEAR Response surface methodology
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