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Optimization of Callus Induction Medium for Schisandga chinensis Baill via Uniform Design 被引量:7
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作者 张佳 金东淳 +1 位作者 金海林 刘权刚 《Agricultural Science & Technology》 CAS 2011年第1期141-143,共3页
[Objective]This study was to optimize callus induction medium for Schisandga chinensis Baill.[Method]Using callus induction rate as an indicator,uniform design was employed to optimize hormone combination at poly-fact... [Objective]This study was to optimize callus induction medium for Schisandga chinensis Baill.[Method]Using callus induction rate as an indicator,uniform design was employed to optimize hormone combination at poly-factors and poly-levels for callus induction from Schisandga chinensis Baill.[Results]Optimal hormone combinations depended on different explants:optimum medium for both tender leaf and petiole was MS +3 mg/L 6-BA,for stem segment was MS +3 mg/L 6-BA +0.6 mg/L NAA.[Conclusion]Uniform design is a time-saving and convenient method for the optimum medium for callus and yields a higher callus induction rate. 展开更多
关键词 Schisandga chinensis Baill Callus tissue uniform design Callus induction rate
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Optimizing Yanbian Cow Oocytes Mature in vitro and Cleavage System after Nuclear Transfer Based on Uniform Design 被引量:6
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作者 苗婷婷 魏世宝 《Agricultural Science & Technology》 CAS 2009年第5期113-115,共3页
[Objective] The aim was to optimize Yanbian cow oocytes mature in vitro and cleavage system after nuclear transfer based on uniform design. [Method] Oocytes were recovered by aspiration method, and oocytes were mature... [Objective] The aim was to optimize Yanbian cow oocytes mature in vitro and cleavage system after nuclear transfer based on uniform design. [Method] Oocytes were recovered by aspiration method, and oocytes were matured in vitro (IVM) with different conditions, and then carried out nucleus transfer, fusion, activation and in vitro culture (IVC) of embryo. Effects of ovary storage temperature, maturation time and follicular diameter size on in vitro maturation and cleavage rates of cow oocytes were compared. [ Result] The best conditions of IVM of Yanbian cow oocytes was that: the oocytes of 8 mm diameter were matured in vitro for 24 hours when the ovaries were stored at 26℃ or 31 ℃. The best cleave conditions after nucleus transfer of oocytes was that: the oocytes of 6 mm or 8 mm diameter were cultured in vitro for 24 hours when the ovaries were stored at 26℃. [ Conclusion] The result has some reference to Yanbian cow and other cow breeding and population expanding propagation. 展开更多
关键词 uniform design Yanbian cow OOCYTES MATURE CLEAVAGE
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Optimizing Efficient Micropropagation System of Rhododendron Brachycarpum D. Don by Uniform Design Method
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作者 姜云天 陈艳秋 +2 位作者 顾地周 李玉梅 曲柏宏 《Agricultural Science & Technology》 CAS 2009年第5期49-51,共3页
[Objective] The study was conducted to establish a high efficient micropropagation system for Rhododendron Brachycarpum D. Don and realize the high efficiency in vitro micropropagation of R. brachycarpum. [ Method ] Y... [Objective] The study was conducted to establish a high efficient micropropagation system for Rhododendron Brachycarpum D. Don and realize the high efficiency in vitro micropropagation of R. brachycarpum. [ Method ] Young stems of R. brachycarpum were used as explants, suitable medium compositions for axillary bud growing and rooting were screened through uniform design exPeriments. [ Result] MS (modified) + IAA 0,15 mg/ L + IBA 0.30 mg/L + GA3 3.00 mg/L was the most suitable medium with the regeneration rate of 92%. Stems each with one node were cut from regenerated shoots and cultured for propagation, the proliferative multiple was over 45 within one culture period of 35 d. [ Conclusion] High efficient micropropagation system of R. brachycarpum has been successfully established, which provides some basis for development and utilization and industrial seedling growth of the alpine rhododendron in Changbai Mountain northeast China. 展开更多
关键词 Rhododendron Brachycarpum D. Don MICROPROPAGATION uniform design
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Uniform Design for Optimizating Regeneration Shoots Directly from Tender Leaves and Plant Regeneration System of Rhododendron chrysanthum Pall. 被引量:3
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作者 李玉梅 姜云天 孙智慧 《Agricultural Science & Technology》 CAS 2008年第6期31-34,共4页
[Objective] The experimental was aimed to screen the optimum regeneration shoot induction media and rooting media for tender leaves of Rhododendron chrysanthum Pall.[Method] The tender leaves of Rhododendron chrysanth... [Objective] The experimental was aimed to screen the optimum regeneration shoot induction media and rooting media for tender leaves of Rhododendron chrysanthum Pall.[Method] The tender leaves of Rhododendron chrysanthum Pall were taken as explants to select the optimum bud induction media and rooting media through uniform design and the screening results were verified.[Result] The optimum media for regeneration shoot of Rhododendron chrysanthum Pall contained 1/4 MS,3.70 mg/L ZT, 0.02 mg/L IAA and 1.00 mg/L KT and its induction rate was 95.5% and the rooting media contained modified MS, 0.10 mg/L IAA and 0.07 mg/L NAA and its rooting rate was 98%. [Conclusion] Through this experiment, regeneration systems for regeneration shoot and regenerated plant from tender leaves of Rhododendron chrysanthum Pall were created successfully. 展开更多
关键词 RHODODENDRON chrysanthum Pall. Tissue culture uniform design
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CONSTRUCTING UNIFORM DESIGNS WITH TWO- OR THREE-LEVEL 被引量:5
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作者 覃红 张尚立 方开泰 《Acta Mathematica Scientia》 SCIE CSCD 2006年第3期451-459,共9页
When the number of runs is large, to search for uniform designs in the sense of low-discrepancy is an NP hard problem. The number of runs of most of the available uniform designs is small (≤50). In this article, th... When the number of runs is large, to search for uniform designs in the sense of low-discrepancy is an NP hard problem. The number of runs of most of the available uniform designs is small (≤50). In this article, the authors employ a kind of the so-called Hamming distance method to construct uniform designs with two- or three-level such that some resulting uniform designs have a large number of runs. Several infinite classes for the existence of uniform designs with the same Hamming distances between any distinct rows are also obtained simultaneously. Two measures of uniformity, the centered L2-discrepancy (CD, for short) and wrap-around L2-discrepancy (WD, for short), are employed. 展开更多
关键词 DISCREPANCY Hadamard matrix Hamming distance uniform design
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Optimization of Culture Conditions and Medium Composition for the Marine Algicidal Bacterium Alteromonas sp. DH46 by Uniform Design 被引量:4
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作者 LIN Jing ZHENG Wei +2 位作者 TIAN Yun WANG Guizhong ZHENG Tianling 《Journal of Ocean University of China》 SCIE CAS 2013年第3期385-391,共7页
Harmful algal blooms(HABs) have led to extensive ecological and environmental issues and huge economic losses.Various HAB control techniques have been developed,and biological methods have been paid more attention.Alg... Harmful algal blooms(HABs) have led to extensive ecological and environmental issues and huge economic losses.Various HAB control techniques have been developed,and biological methods have been paid more attention.Algicidal bacteria is a general designation for bacteria which inhibit algal growth in a direct or indirect manner,and kill or damage the algal cells.A metabolite which is strongly toxic to the dinoflagellate Alexandrium tamarense was produced by strain DH46 of the alga-lysing bacterium Alteromonas sp.The culture conditions were optimized using a single-factor test method.Factors including carbon source,nitrogen source,temperature,initial pH value,rotational speed and salinity were studied.The results showed that the cultivation of the bacteria at 28℃ and 180 r min-1with initial pH 7 and 30 salt contcentration favored both the cell growth and the lysing effect of strain DH46.The optimal medium composition for strain DH46 was determined by means of uniform design experimentation,and the most important components influencing the cell density were tryptone,yeast extract,soluble starch,NaNO3 and MgSO4.When the following culture medium was used(tryptone 14.0g,yeast extract 1.63g,soluble starch 5.0 g,NaNO3 1.6 g,MgSO4 2.3 g in 1L),the largest bacterial dry weight(7.36 g L-1) was obtained,which was an enhancement of 107% compared to the initial medium;and the algal lysis rate was as high as 98.4% which increased nearly 10% after optimization. 展开更多
关键词 algicidal bacteria OPTIMIZATION culture conditions medium composition uniform design
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Optimization of tensile strength for new type acetone-urea-formaldehyde furan resin using uniform design 被引量:5
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作者 Lin Shengjun Zhao Wei +2 位作者 Li Yuancai Tong Siyi Wang Wenqing 《China Foundry》 SCIE CAS 2011年第1期30-35,共6页
In this study,the 24 h tensile strength of new type acetone-urea-formaldehyde furan resin (nitrogen content 3%) was investigated by uniform design optimization.Four independent variables such as acetone:formaldehyde m... In this study,the 24 h tensile strength of new type acetone-urea-formaldehyde furan resin (nitrogen content 3%) was investigated by uniform design optimization.Four independent variables such as acetone:formaldehyde molar ratio (mol/mol),solution pH value,reaction temperature (℃) and reaction time (min) were considered in the experiments.U13(134) uniform design was employed and the equation of 24 h tensile strength model was obtained after 13 experimentations.The 24 h tensile strength was optimized by applying single factor experiments and stepwise non-linear regression analysis.Minitab (Minitab 15 trial version) and MATLAB (R2010a trial version) were used for data analysis.The t-value and p-value indicate that the major impact factors include the interaction effect of solution pH value and reaction temperature (X2X3),the linear terms of acetone:formaldehyde molar ratio (X1),reaction time (X4) followed by the square effects of acetone/formaldehyde molar ratio (X1X1).The optimized results were achieved with the acetone:formaldehyde molar ratio (mol/mol) at 3:1,solution pH value at 6.0,reaction temperature at 70℃,and reaction time at 140 min,respectively.This method can not only significantly reduce the number and cost of the tests,but also provide a good experimental design strategy for the development of furan resin.The investigation shows that the predicted results of 24 h tensile strength are consistent well with the experimental ones. 展开更多
关键词 acetone-urea-formaldehyde furan resin 24 h tensile strength single factor experiment uniform design stepwise regression
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The height-width ratio limited value for rubber bearing isolated structure computed by uniform design method 被引量:7
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作者 王铁英 王焕定 +1 位作者 张永山 刘文光 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第1期36-40,共5页
Rubber isolation is the most mature control technology in practical application, and is widely used by short rigid buildings. However, many high isolation buildings have been built around the world in recent years, wh... Rubber isolation is the most mature control technology in practical application, and is widely used by short rigid buildings. However, many high isolation buildings have been built around the world in recent years, which do not follow the existing criterions and codes. Many researchers began to research the special problems caused by larger height-width ratio isolation structures. The overturning effect of high height-width ratio structures with rubber bearing is firstly studied. Considering the main factors, such as the height-width ratio of structures, type of site, the designed basic acceleration of ground motion and the decouple factor in horizon, computing experiment is defined with the Uniform Design Method, which is also known as designing isolation structure. The forces of the bearing under edge of structures based on the position of the rubber bearing are calculated. The result indicates that the rubber bearings will lose its functionality under very high tension and compressing force of earthquake motion in horizon and vertical, when the height-width ratio is over a certain value. Thus, based on the calculation result of isolation structures defined in the uniform design method, regression analysis is conducted, and also the rubber edge force regression formula are gotten, which has higher correlation and smaller standard deviation. This formula can be used to roughly calculate whether the pull force occurs at the edge of the building. By the edge bearings of isolation structure minimum force formula, the height-width ratio limited value of the isolation structure is deducted when rubber bearing has minimum force of zero. 展开更多
关键词 isolation structures the uniform design method regression analysis height-width ratio limited value
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Integration of uniform design and quantum-behaved particle swarm optimization to the robust design for a railway vehicle suspension system under different wheel conicities and wheel rolling radii 被引量:2
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作者 Yung-Chang Cheng Cheng-Kang Lee 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2017年第5期963-980,共18页
This paper proposes a systematic method, integrating the uniform design (UD) of experiments and quantum-behaved particle swarm optimization (QPSO), to solve the problem of a robust design for a railway vehicle suspens... This paper proposes a systematic method, integrating the uniform design (UD) of experiments and quantum-behaved particle swarm optimization (QPSO), to solve the problem of a robust design for a railway vehicle suspension system. Based on the new nonlinear creep model derived from combining Hertz contact theory, Kalker's linear theory and a heuristic nonlinear creep model, the modeling and dynamic analysis of a 24 degree-of-freedom railway vehicle system were investigated. The Lyapunov indirect method was used to examine the effects of suspension parameters, wheel conicities and wheel rolling radii on critical hunting speeds. Generally, the critical hunting speeds of a vehicle system resulting from worn wheels with different wheel rolling radii are lower than those of a vehicle system having original wheels without different wheel rolling radii. Because of worn wheels, the critical hunting speed of a running railway vehicle substantially declines over the long term. For safety reasons, it is necessary to design the suspension system parameters to increase the robustness of the system and decrease the sensitive of wheel noises. By applying UD and QPSO, the nominal-the-best signal-to-noise ratio of the system was increased from -48.17 to -34.05 dB. The rate of improvement was 29.31%. This study has demonstrated that the integration of UD and QPSO can successfully reveal the optimal solution of suspension parameters for solving the robust design problem of a railway vehicle suspension system. 展开更多
关键词 Speed-dependent nonlinear creep model Quantum-behaved particle swarm optimization uniform design Wheel rolling radius Hunting stability
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Process parameter optimization for local post-weld heat treatment.of turbine rotor based on uniform design 被引量:1
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作者 王开云 陆皓 +2 位作者 余春 曹志明 顾福明 《China Welding》 EI CAS 2012年第3期44-49,共6页
During the process of local post-weld heat treatment ( PWHT) , the temperature difference inside the weld overlay is a very influential factor on relieving residual stress. In this paper, a commercial program (ABA... During the process of local post-weld heat treatment ( PWHT) , the temperature difference inside the weld overlay is a very influential factor on relieving residual stress. In this paper, a commercial program (ABAQUS) was used to simulate the temperature field in turbine rotor, and the influence of heat treatment parameters on temperature was investigated by finite element method. Weight analysis shows that the holding temperature and heating rate are the main factors affecting on temperature, especially the holding temperature. Besides, two regression equations that reflect the relationship between temperature and heat treatment parameters were fitted with uniform design method. Both the correlation coefficients of the regression equations are up to O. 999 2, and the maximum residual error is only O. 7. The agreement between simulation results and regression results is shown to be excellent. At the end, local heat treatment parameters were optimized using the simplex method. 展开更多
关键词 turbine rotor parameter optimization uniform design
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Extraction optimization of coumarins from radix angelicae pubescentis by HPLC-DAD coupled with uniform design 被引量:1
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作者 郭方遒 黄兰芳 +1 位作者 周火飞 江秋菊 《Journal of Central South University of Technology》 EI 2006年第2期156-159,共4页
Uniform design was used to optimize extraction condition of direct refluence extraction of coumarins from the Chinese traditional medicine of radix angelicae pubescentis(Duhuo); the sum peak area of coumarins separate... Uniform design was used to optimize extraction condition of direct refluence extraction of coumarins from the Chinese traditional medicine of radix angelicae pubescentis(Duhuo); the sum peak area of coumarins separated with high performance liquid chromatography(HPLC) at detection wavelength of 320nm was considered as detection index, two factors of solvent concentration and extraction time were mainly studied at extraction temperature of 85℃ and a volume ratio of solvent to sample of 10∶1. Optimal subclass, quadric polynomial step by step aggression and neural network method were applied to process the experimental results. The results show that the first and second methods give the same factors combination (concentration of ethanol: 95%, extraction time: 3.6 h) and the second method is much better than the first one. The extraction model is consequently developed. 展开更多
关键词 radix angelicae pubescentis(Duhuo) couamrins uniform design high performance liquid chromatagraphy-diode array detector(HPLC-DAD)
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Simulation and uniform design-based automatic generation of risk scenarios
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作者 Jinghui Li Rui Kang +1 位作者 Ali Mosleh Xing Pan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第6期1015-1022,共8页
This paper presents a methodology for automatically generating risk scenarios for dynamic reliability applications in which some dynamic characteristics(e.g.,the order,timing and magnitude of events,the value of relev... This paper presents a methodology for automatically generating risk scenarios for dynamic reliability applications in which some dynamic characteristics(e.g.,the order,timing and magnitude of events,the value of relevant process parameters and initial conditions) have a significant influence on the evolution of the system.The main idea of the methodology is:(i) making the system model "express itself" through simulation by having the model driven by an elaborated simulation engine;(ii) exploiting uniform design to pick out a small subset of representative design points from the space of relevant dynamic characteristics;(iii) for each selected design point,employing a depth-first systematic exploration strategy to cover all possible scenario branches at each branch point.A highly dynamic example adapted from the literature(a chemical batch reactor) is studied to test the effectiveness of the proposed methodology. 展开更多
关键词 risk scenarios automatic generation SIMULATION uniform design dynamic reliability.
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A study of arc stability of basic electrode in view of uniform design method
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作者 孟工戈 金龙浩 杨拓宇 《China Welding》 EI CAS 2007年第3期32-35,共4页
In order to develop a basic electrode with low fume and good usability, a uew slag system has been designed after analyzing several basic electrode slag systems. Then in view of uniform design method, arranging the ex... In order to develop a basic electrode with low fume and good usability, a uew slag system has been designed after analyzing several basic electrode slag systems. Then in view of uniform design method, arranging the experiment points by it, the influenced laws of the uew system coating compouents on the arc stability had been searched. In the formula, niue coating compouents were taken as independent variables and they were divided into six levels in all twenty-four experiments. The arc stability was taken as function and taken down the data when welding and then put them into the computer to be processed statistically. The analysis results give the mathematical model and trend diagrams between independent variables and the function. They indicate that the effects of many coating compouents on the arc stability are in the mutual form. The mutual effects between CaCO3 and BaF2, BaF2 and BaCO3 , increases the arc stability separately. While the mutual effects between CaF2 and iron powder, the square item of iron powder itself decreases the arc stability separately. 展开更多
关键词 basic electrode arc stability uniform design
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Application of Uniform Design and SVR for Culture Medium Optimization of Organophosphorus Degradation Bacteria
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作者 TAN Xian-sheng ZHU Xiong-mei +5 位作者 ZHOU Yu-liang LI Wei-wei LIU Li-na HU Jun-he JIN Chen-zhong LI Wen-juan 《Agricultural Science & Technology》 CAS 2018年第6期43-47,共5页
In order to improve the degradation activity of organophosphorus degradation bacterial strains, uniform design and support vector regression(SVR) are used to optimize the formula of mineral salt medium for the strains... In order to improve the degradation activity of organophosphorus degradation bacterial strains, uniform design and support vector regression(SVR) are used to optimize the formula of mineral salt medium for the strains based on single factor experiment. The formula being used after SVR optimization is glucose 1.24 g/L,NH4 NO3 0.73 g, KH2 PO4 0.96 g, KCl 0.50 g, MgSO4·7 H2 O 0.50 g, MnSO4 0.02 g, CaCl2 0.04 g, distilled water 1 000 mL;the highest degradation rate is obtained at pH7.0(SVR, 76.68%), superior to that of the QSAR model(74.67%). The formula optimization method based on uniform design and SVR is very promising to apply in various multiple-factor and multiple-level formula optimization experiments. 展开更多
关键词 Organophosphorus degradation bacteria uniform design Support Vector Regression(SVR) formula optimization
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Investigation of paeonol-geniposide on acute alcoholic liver injury based on uniform design method
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作者 LIU Ke LIU Yu-long +3 位作者 SUN Min LIU Ling-ling ZHANG Lu-ning YAN Gui-ming 《Journal of Hainan Medical University》 2022年第24期25-31,共7页
Objective:To explore the optimal ratio and compatibility effect of paeonol-geniposide combination on acute alcoholic liver injury by uniform design.Methods:Lieber-DeCarli alcoholic liquid feed was used to induce acute... Objective:To explore the optimal ratio and compatibility effect of paeonol-geniposide combination on acute alcoholic liver injury by uniform design.Methods:Lieber-DeCarli alcoholic liquid feed was used to induce acute alcoholic liver injury in mice.Uniform design was used to select the best dosage combination of paeonol and geniposide,and the related indexes of liver injury and oxidative stress were detected by kit.Serum inflammatory factors were detected by ELISA,and the expressions of p38 MAPK,JNK and NF-κB P65 related proteins in liver were detected by Western-blot.Results:The regression equation suggested that paeonol:geniposide=220:20 was the best ratio of paeonol and geniposide to resist alcoholic liver injury.Compared with the model group,the liver injury indexes and oxidation products of the paeonol+geniposide group decreased significantly,the antioxidant activity of liver tissue increased significantly,and the expression levels of p-p38 MAPK,p-JNK and NF-κB P65 protein decreased significantly.Conclusion:The optimal dosage of paeonolgeniposide was effectively optimized by uniform design and pharmacodynamic analysis.The combination of the two drugs could reduce the alcoholic liver injury by reducing the oxidative stress injury and inflammatory response in the liver tissue of mice,and its effect might be related to the targeting of p38 MAPK/JNK/NF-κB channel. 展开更多
关键词 PAEONOL GENIPOSIDE Alcoholic liver injury uniform design Chinese medicine effective ingredient ratio
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Optimizational production of phenyllactic acid by a Lactobacillus buchneri strain via uniform design with overlay sampling methodology 被引量:4
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作者 Jintao Guan Chaofei Han +3 位作者 Yixin Guan Songhong Zhang Junxian Yun Shanjing Yao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第2期418-425,共8页
A Lactobacillus buchneri GBS3 strain isolated from the traditional Chinese pickles was used for the production of 3-phenyllactic acid(PLA), an important compound with antimicrobial activities against a wide species of... A Lactobacillus buchneri GBS3 strain isolated from the traditional Chinese pickles was used for the production of 3-phenyllactic acid(PLA), an important compound with antimicrobial activities against a wide species of grampositive and gram-negative bacteria and some fungi. The growth performance of this strain in the de Man, Rogosa and Sharpe(MRS) medium, the production of metabolites of valuable organic acids, and the biosynthesis of PLA using this strain as the whole-cell biocatalyst and phenylpyruvic acid(PPA) as the precursor, were investigated experimentally. The uniform design method with overlay sampling was developed for the optimization of the biotransformation conditions. The results showed that although it produced naturally lactic acid with the maximum concentration of 1.84 g·L^(-1) and PLA with the concentration of 0.015 g·L^(-1) after 66 to 72 h cultivation in MRS broth by fermentation, the present strain displayed an effective utilization ability by transforming PPA to PLA. By the uniform design method with overlay sampling for the design and optimization of transformation conditions, a maximum yield of 10.93 g·L^(-1) PLA with the mole conversion ratio of 83.07% from PPA to PLA was achieved under the optimized condition, i.e., 20 g·L^(-1) glucose, 270 g·L^(-1) cells, 13 g·L^(-1) PPA, pH 8.0 and the reaction time of 15 h, indicating that Lactobacillus buchneri GBS3 was an interesting strain for the biosynthesis of PLA via the microbial transformation. The prediction of PLA yield under different conditions was achieved successfully based on the limited information of only a small number of experiments by the uniform design with overlay sampling. Therefore, the present methodology is effective and helpful for the optimization of the biosynthesis processes of PLA. 展开更多
关键词 Phenyllactic ACID Biotransformati on LACTOBACILLUS Buchneri uniform design OVERLAP Sampling
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Research on the design method for uniform wear of shield cutters in sand-pebble strata
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作者 Jinxun Zhang Bo Li +4 位作者 Guihe Wang Yusheng Jiang Hua Jiang Minglun Yin Zhengyang Sun 《Deep Underground Science and Engineering》 2024年第2期216-230,共15页
During shield tunneling in highly abrasive formations such as sand–pebble strata,nonuniform wear of shield cutters is inevitable due to the different cutting distances.Frequent downtimes and cutter replacements have ... During shield tunneling in highly abrasive formations such as sand–pebble strata,nonuniform wear of shield cutters is inevitable due to the different cutting distances.Frequent downtimes and cutter replacements have become major obstacles to long-distance shield driving in sand–pebble strata.Based on the cutter wear characteristics in sand–pebble strata in Beijing,a design methodology for the cutterhead and cutters was established in this study to achieve uniform wear of all cutters by the principle of frictional wear.The applicability of the design method was verified through three-dimensional simulations using the engineering discrete element method.The results show that uniform wear of all cutters on the cutterhead could be achieved by installing different numbers of cutters on each trajectory radius and designing a curved spoke with a certain arch height according to the shield diameter.Under the uniform wear scheme,the cutter wear coefficient is greatly reduced,and the largest shield driving distance is increased by approximately 47%over the engineering scheme.The research results indicate that the problem of nonuniform cutter wear in shield excavation could be overcome,thereby providing guiding significance for theoretical innovation and construction of long-distance shield excavation in highly abrasive strata. 展开更多
关键词 cutter wear EDEM model long-distance shield driving sand-pebble stratum shield tunnel uniform wear design method
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An Adjusted Gray Map Technique for Constructing Large Four-Level Uniform Designs
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作者 ELSAWAH A M VISHWAKARMA G K +1 位作者 MOHAMED H S FANG Kai-Tai 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2023年第1期433-456,共24页
A uniform experimental design(UED)is an extremely used powerful and efficient methodology for designing experiments with high-dimensional inputs,limited resources and unknown underlying models.A UED enjoys the followi... A uniform experimental design(UED)is an extremely used powerful and efficient methodology for designing experiments with high-dimensional inputs,limited resources and unknown underlying models.A UED enjoys the following two significant advantages:(i)It is a robust design,since it does not require to specify a model before experimenters conduct their experiments;and(ii)it provides uniformly scatter design points in the experimental domain,thus it gives a good representation of this domain with fewer experimental trials(runs).Many real-life experiments involve hundreds or thousands of active factors and thus large UEDs are needed.Constructing large UEDs using the existing techniques is an NP-hard problem,an extremely time-consuming heuristic search process and a satisfactory result is not guaranteed.This paper presents a new effective and easy technique,adjusted Gray map technique(AGMT),for constructing(nearly)UEDs with large numbers of four-level factors and runs by converting designs with s two-level factors and n runs to(nearly)UEDs with 2^(t−1)s four-level factors and 2tn runs for any t≥0 using two simple transformation functions.Theoretical justifications for the uniformity of the resulting four-level designs are given,which provide some necessary and/or sufficient conditions for obtaining(nearly)uniform four-level designs.The results show that the AGMT is much easier and better than the existing widely used techniques and it can be effectively used to simply generate new recommended large(nearly)UEDs with four-level factors. 展开更多
关键词 ABERRATION adjusted Gray map technique Gray map technique Hamming distance moment aberration threshold accepting algorithm uniform design
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Uniform design ray in the assessment of combined toxicities of multi-component mixtures 被引量:22
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作者 Shu-Shen Liu Qian-Fen Xiao +1 位作者 Jin Zhang Mo Yu 《Science Bulletin》 SCIE EI CAS CSCD 2016年第1期52-58,共7页
Multi-component mixture(MCM) is a complicated chemical system that contains a great deal of mixture rays with various mixture ratios, and each ray includes many mixtures with different concentration levels.Currently, ... Multi-component mixture(MCM) is a complicated chemical system that contains a great deal of mixture rays with various mixture ratios, and each ray includes many mixtures with different concentration levels.Currently, in combined toxicity field, almost all studies on MCM focus on the mixtures designed by the equivalenteffect concentration ratio(EECR) procedure. However, the EECR mixtures cannot represent the whole mixture system because the EECR mixtures are located on one mixture ray in concentration space formed by multiple components. In our view, some optimal experimental design such as the uniform design(UD) should be used to effectively select many representative mixture rays from the MCM system,instead of single EECR ray. The uniform design ray(UDray) integrating UD idea with fixed-ratio ray design can systematically and comprehensively measure the combined toxicity changes in the MCM system. This review introduces the operation method, construction of uniform table and corresponding usable table, and some cases of application of the UD-ray to help readers easily use UD-ray in their MCM toxicity assessment. 展开更多
关键词 Chemical mixture uniform design Ray design Mixture ratio. Concentration-responserelationship Toxicity interaction
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Optimization of H_2O_2 dosage in microwave-H_2O_2 process for sludge pretreatment with uniform design method 被引量:12
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作者 Qingcong Xiao Hong Yan +3 位作者 Yuansong Wei Yawei Wang Fangang Zeng Xiang Zheng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第12期2060-2067,共8页
A microwave-H202 process for sludge pretreatment exhibited high efticiencies of releasing organics, nitrogen, and phosphorus, but large quantifies of H202 residues were detected. A uniform design method was thus emplo... A microwave-H202 process for sludge pretreatment exhibited high efticiencies of releasing organics, nitrogen, and phosphorus, but large quantifies of H202 residues were detected. A uniform design method was thus employed in this study to further optimize H202 dosage by investigating effects of pH and H202 dosage on the amount of 1-I202 residue and releases of organics, nitrogen, and phosphorus. A regression model was established with pH and H202 dosage as the independent variables, and H202 residue and releases of organics, nitrogen, and phosphorus as the dependent variables. In the optimized microwave-H202 process, the pH value of the sludge was firstly adjusted to 11.0, then the sludge was heated to 80~C and H202 was dosed at a H202 :mixed liquor suspended solids (MLSS) ratio of 0.2, and the sludge was finally heated to 100~C by microwave irradiation. Compared to the microwave-H202 process without optimization, the H202 dosage and the utilization rate of H202 in the optimized microwave-H202 process were reduced by 80% and greatly improved by 3.87 times, respectively, when the H202:MLSS dosage ratio was decreased from 1.0 to 0.2, resulting in nearly the same release rate of soluble chemical oxygen demand in the microwave-H202 process without optimization at H202:MLSS ratio of 0.5. 展开更多
关键词 H2O2 dosage uniform design method MICROWAVE OPTIMIZATION sludge pretreatment
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