This study discussed the application of response surface methodology(RSM)and central composite rotatable design(CCRD)for modeling and optimization of the influence of some operating variables on the performance of a l...This study discussed the application of response surface methodology(RSM)and central composite rotatable design(CCRD)for modeling and optimization of the influence of some operating variables on the performance of a lab scale thickener for dewatering of tailing in the flotation circuit.Four thickener operating variables,namely feed flowrate,solid percent,flocculant dosage and feedwell height were changed during the tests based on CCRD.The ranges of values of the thickener variables used in the design were a feed flowrate of 9–21 L/min,solid percent of 8%–20%,flocculant dosage of 1.25–4.25 g/t and feedwell height of 16–26 cm.A total of 30 thickening tests were conducted using lab scale thickener on flotation tailing obtained from the Sarcheshmeh copper mine,Iran.The underflow solid percent and bed height were expressed as functions of four operating parameters of thickener.Predicted values were found to be in good agreement with experimental values(R2values of 0.992 and 0.997 for underflow solid percent and bed height,respectively).This study has shown that the RSM and CCRD could effciently be applied for the modeling of thickener for dewatering of flotation tailing.展开更多
The conversion of rice hulls into fermentable saccharides was explored through steam pretreatment employing 2.5% SO_(2).The in teraction between temperature and time was assessed by means of the response surface metho...The conversion of rice hulls into fermentable saccharides was explored through steam pretreatment employing 2.5% SO_(2).The in teraction between temperature and time was assessed by means of the response surface method to achieve optimum contents of C6-sugars in water-insoluble solids(WIS)and C5-sugars in the liquor.Pretreatment carried out at 218℃ for 2.3 min released liquor containing 55.4 g/L of sugars(29.1 g/L of xylose).In parallel,the WIS was subjected to enzymatic saccharification using different solid and enzyme loads via an experimental design:assays using 22.0% WIS and 20.0 filter paper units(FPU)/g led to 90.6 g/L of glucose,corresponding to a yield of 86.4% and an overall yield of 72.4%.The data reported are the highest ever found for such raw material,making it attractive to compete with conventi on al lig no cellulosic biomass.展开更多
Rotatability is a desirable quality of fitting response surface experimental designs. The propertystates that the variance of the estimated response made from the Taylor’s series expansion areconstant on circles, sph...Rotatability is a desirable quality of fitting response surface experimental designs. The propertystates that the variance of the estimated response made from the Taylor’s series expansion areconstant on circles, spheres and hyper-spheres about the centre of the design. In this article,a measure of rotatability of modified second-order rotatable design is presented. The variancefunction of a second-order response design and an infinite class of supplementary difference setsis used in coming up with the design.展开更多
The technique of fitting a response surface design is useful in modelling of experimental designs.Response surface is used in situations where the response of interest is influenced by several experimental variables.T...The technique of fitting a response surface design is useful in modelling of experimental designs.Response surface is used in situations where the response of interest is influenced by several experimental variables.The objective of fitting a response surface design is to reduce cost of experimentation and to obtain optimal designs.The property of rotatability is a desirable quantity of experimental design and requires the variance of the fitted design to be constant on circles or spheres about the centre of the design.In this article,a construction technique of fitting modified non-sequential third order rotatable design(TORD)using Pairwise Balanced Design(PBD)is presented.The variance function of a third order response surface design and the properties of Pairwise Balanced Design are utilised for the construction.展开更多
We propose a novel non-contact rotational sensor based on a fiber Bragg grating(FBG) packaged in a core of a magnetic head, which converts the introduced strain from the circular magnetic railings ruler into the rotat...We propose a novel non-contact rotational sensor based on a fiber Bragg grating(FBG) packaged in a core of a magnetic head, which converts the introduced strain from the circular magnetic railings ruler into the rotational information. A mathematical model is built for processing the data obtained by an interrogator, and the accuracy and resolution of the measurements are analyzed by altering the radius and period of the circular magnetic railings ruler, as well as the dimension of the sensor. The experimental results show that it is in good accordance with the theoretical analysis on rotational angle, and the fitting results indicate that the results obtained from the rotational sensor match very well with the real rotational velocity with a linearity of 0.998 and a standard error of about 0.01.展开更多
Glyphosate is an important organophosphonate herbicide used to eliminate grasses and herbaceous plants in many vegetation management situations.Its extensive use is causing environmental pollution,and consequently,the...Glyphosate is an important organophosphonate herbicide used to eliminate grasses and herbaceous plants in many vegetation management situations.Its extensive use is causing environmental pollution,and consequently,there is a need to remove it from the environment using an eco-friendly and cost-effective method.As a step to address this problem,a novel bacterial strain Comamonas odontotermitis F2,capable to utilize glyphosate as a carbon(C)and/or phosphorus(P)source,was isolated from a glyphostate-contaminated field soil in Australia and characterized.Response surface methodology(RSM)employing a 2^3 full factorial central composite design was used to optimize glyphosate degradation by C.odontotermitis P2 under various culture conditions.The strain C.odontotermitis P2 was proficient in degrading 1.5 g L^-1 glyphosate completely within 104 h.The optimal conditions for the degradation of glyphosate were found to be pH 7.4,29.9℃,and an inoculum density of 0.54 g L^-1,resulting in a maximum degradation of 90%.Sequencing of glyphosate oxidoreductase(GOX)and C-P lyase(phnJ)genes from C.odontotermitis P2 revealed 999c and 93%identities to already reported bacterial GOX and phnJ genes,respectively.The presence of these two genes in C.odontotermitis indicates its potential to degrade glyphosate through GOX and C-P lyase metabolic pathways.This study demonstrates the potential of C.odontotermitis P2 for efficient degradation of glyphosate,which can be exploited for remediation of glyphosate.展开更多
Though subjective feelings affected by lighting have been studied a lot,multivariate experimental studies are lacking in this research field.Central composite rotatable design(CCRD)was applied to investigate the influ...Though subjective feelings affected by lighting have been studied a lot,multivariate experimental studies are lacking in this research field.Central composite rotatable design(CCRD)was applied to investigate the influence of illuminance,correlated color temperature(CCT)and illuminance uniformity on satisfaction in this study.A series of subject experiments were carried out and polynomial regression models of luminous satisfaction for different activity scenarios were generated.Illuminance and CCT affected the satisfaction significantly in visual task scenarios,and the effect of them was independent with each other,which was demonstrated by the regression model(R2=0.89).The variation of luminous satisfaction in general activity scenarios cannot be fully explained by the three investigated factors.The results contributed to the knowledge of multivariate analysis of luminous environment and indicated that much could be expected referring to the application of CCRD in this field.展开更多
基金supported by the National Iranian Copper Industry Co.
文摘This study discussed the application of response surface methodology(RSM)and central composite rotatable design(CCRD)for modeling and optimization of the influence of some operating variables on the performance of a lab scale thickener for dewatering of tailing in the flotation circuit.Four thickener operating variables,namely feed flowrate,solid percent,flocculant dosage and feedwell height were changed during the tests based on CCRD.The ranges of values of the thickener variables used in the design were a feed flowrate of 9–21 L/min,solid percent of 8%–20%,flocculant dosage of 1.25–4.25 g/t and feedwell height of 16–26 cm.A total of 30 thickening tests were conducted using lab scale thickener on flotation tailing obtained from the Sarcheshmeh copper mine,Iran.The underflow solid percent and bed height were expressed as functions of four operating parameters of thickener.Predicted values were found to be in good agreement with experimental values(R2values of 0.992 and 0.997 for underflow solid percent and bed height,respectively).This study has shown that the RSM and CCRD could effciently be applied for the modeling of thickener for dewatering of flotation tailing.
基金supported by Coordination for the Improvement of Higher Education Personnel Foundation,Mmistry of Education in Brazil(Grant No.POS-DOC-88881.170076/2018-01).
文摘The conversion of rice hulls into fermentable saccharides was explored through steam pretreatment employing 2.5% SO_(2).The in teraction between temperature and time was assessed by means of the response surface method to achieve optimum contents of C6-sugars in water-insoluble solids(WIS)and C5-sugars in the liquor.Pretreatment carried out at 218℃ for 2.3 min released liquor containing 55.4 g/L of sugars(29.1 g/L of xylose).In parallel,the WIS was subjected to enzymatic saccharification using different solid and enzyme loads via an experimental design:assays using 22.0% WIS and 20.0 filter paper units(FPU)/g led to 90.6 g/L of glucose,corresponding to a yield of 86.4% and an overall yield of 72.4%.The data reported are the highest ever found for such raw material,making it attractive to compete with conventi on al lig no cellulosic biomass.
文摘Rotatability is a desirable quality of fitting response surface experimental designs. The propertystates that the variance of the estimated response made from the Taylor’s series expansion areconstant on circles, spheres and hyper-spheres about the centre of the design. In this article,a measure of rotatability of modified second-order rotatable design is presented. The variancefunction of a second-order response design and an infinite class of supplementary difference setsis used in coming up with the design.
文摘The technique of fitting a response surface design is useful in modelling of experimental designs.Response surface is used in situations where the response of interest is influenced by several experimental variables.The objective of fitting a response surface design is to reduce cost of experimentation and to obtain optimal designs.The property of rotatability is a desirable quantity of experimental design and requires the variance of the fitted design to be constant on circles or spheres about the centre of the design.In this article,a construction technique of fitting modified non-sequential third order rotatable design(TORD)using Pairwise Balanced Design(PBD)is presented.The variance function of a third order response surface design and the properties of Pairwise Balanced Design are utilised for the construction.
基金supported by the Program for Cheung Kong Scholars and Innovative Research Team in University(No.IRT1212)the Project Plan of Beijing Municipal Science and Technology Commission(No.Z151100003615010)the Project Plan of Beijing Municipal Education Commission for Enhancing the Innovation Capability in 2015(No.TJSHG201510772016)
文摘We propose a novel non-contact rotational sensor based on a fiber Bragg grating(FBG) packaged in a core of a magnetic head, which converts the introduced strain from the circular magnetic railings ruler into the rotational information. A mathematical model is built for processing the data obtained by an interrogator, and the accuracy and resolution of the measurements are analyzed by altering the radius and period of the circular magnetic railings ruler, as well as the dimension of the sensor. The experimental results show that it is in good accordance with the theoretical analysis on rotational angle, and the fitting results indicate that the results obtained from the rotational sensor match very well with the real rotational velocity with a linearity of 0.998 and a standard error of about 0.01.
基金We acknowledge Higher Education Commission (HEC), Islamabad, Pakistan, for providing financial support through International Research Support Initiative Program (IRSIP) to conduct this research at University of Sydney, Australia.
文摘Glyphosate is an important organophosphonate herbicide used to eliminate grasses and herbaceous plants in many vegetation management situations.Its extensive use is causing environmental pollution,and consequently,there is a need to remove it from the environment using an eco-friendly and cost-effective method.As a step to address this problem,a novel bacterial strain Comamonas odontotermitis F2,capable to utilize glyphosate as a carbon(C)and/or phosphorus(P)source,was isolated from a glyphostate-contaminated field soil in Australia and characterized.Response surface methodology(RSM)employing a 2^3 full factorial central composite design was used to optimize glyphosate degradation by C.odontotermitis P2 under various culture conditions.The strain C.odontotermitis P2 was proficient in degrading 1.5 g L^-1 glyphosate completely within 104 h.The optimal conditions for the degradation of glyphosate were found to be pH 7.4,29.9℃,and an inoculum density of 0.54 g L^-1,resulting in a maximum degradation of 90%.Sequencing of glyphosate oxidoreductase(GOX)and C-P lyase(phnJ)genes from C.odontotermitis P2 revealed 999c and 93%identities to already reported bacterial GOX and phnJ genes,respectively.The presence of these two genes in C.odontotermitis indicates its potential to degrade glyphosate through GOX and C-P lyase metabolic pathways.This study demonstrates the potential of C.odontotermitis P2 for efficient degradation of glyphosate,which can be exploited for remediation of glyphosate.
基金This work was supported by the National Key R&D Program of China(2017YFC0703503).
文摘Though subjective feelings affected by lighting have been studied a lot,multivariate experimental studies are lacking in this research field.Central composite rotatable design(CCRD)was applied to investigate the influence of illuminance,correlated color temperature(CCT)and illuminance uniformity on satisfaction in this study.A series of subject experiments were carried out and polynomial regression models of luminous satisfaction for different activity scenarios were generated.Illuminance and CCT affected the satisfaction significantly in visual task scenarios,and the effect of them was independent with each other,which was demonstrated by the regression model(R2=0.89).The variation of luminous satisfaction in general activity scenarios cannot be fully explained by the three investigated factors.The results contributed to the knowledge of multivariate analysis of luminous environment and indicated that much could be expected referring to the application of CCRD in this field.