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Application of Uniform Experimental Design in Optimizing Excitation Parameters for Magnetic Frequency Mixing Measurements 被引量:2
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作者 Yu Chang Jingpin Jiao +3 位作者 Xiucheng Liu Guanghai Li Cunfu He Bin Wu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2020年第1期197-209,共13页
Excitation parameter preferences are key factors a ecting the performance of magnetic frequency mixing detection.A uniform experimental design method was used to analyze this influence.Using fuzzy theory,a comprehensi... Excitation parameter preferences are key factors a ecting the performance of magnetic frequency mixing detection.A uniform experimental design method was used to analyze this influence.Using fuzzy theory,a comprehensive model is established for evaluating the e ect of magnetic frequency mixing.A polynomial is selected as the regression function to express explicitly the correlation between the excitation parameters and the frequency-mixing e ect.The excitation parameters were then optimized using genetic algorithm.Magnetic frequency mixing experiments were conducted to measure the surface hardness of some ferromagnetic materials.Frequency mixing is further enhanced under the optimal settings,resulting in an improvement in the measurement sensitivity.The results of this study support the application of the magnetic frequency mixing technique in non-destructive testing. 展开更多
关键词 MAGNETIC frequency MIXING technology EXCITATION parameters UNIFORM experimental design Regression STATISTICAL method Surface HARDNESS measurement
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Design of a Simulator for Enhanced Oil Recovery Process Using a Nigerian Reservoir as a Case Study
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作者 Kamilu Folorunsho Oyedeko Alfred Akpoveta Susu 《Advances in Chemical Engineering and Science》 2014年第4期430-453,共24页
This study involves the applications of different numerical techniques in a more general way to the design of a simulator for an enhanced oil recovery process with surfactant assisted water flooding. The data from a h... This study involves the applications of different numerical techniques in a more general way to the design of a simulator for an enhanced oil recovery process with surfactant assisted water flooding. The data from a hypothetical oil well and a Nigerian oil well were used for the validation of the simulator. The process is represented by a system of nonlinear partial differential equations: the continuity equation for the transport of the components and Darcy’s equation for the phase flow. The orthogonal collocation, finite difference and coherence theory techniques were used in solving the equations that characterized the multidimensional, multiphase and multicomponent flow problem. Matlab computer programs were used for the numerical solution of the model equ- ations. The predicted simulator, obtained from the resulting numerical exercise confers uncondi- tional stability and more insight into the physical reservoir description. The results of the ortho- gonal collocation solution were compared with those of finite difference and coherence solutions. The results indicate that the concentration of surfactants for orthogonal collocation show more features than the predictions of the coherence solution and the finite difference, offering more opportunities for further understanding of the physical nature of the complex problem. We have found out that the partition of the three components between the two-phases determines other physical property data and hence the oil recovery. The oil recovery for the Nigerian oil reservoir is higher than the recovery predicted for the hypothetical crude. The displacement mechanism for the multicomponent and multiphase system is stable in the Nigerian oil reservoir due to the mod- erate value of the oil/water viscosity instead of the hypothetical reservoir with high value of oil/water ratio. 展开更多
关键词 Enhanced oil Recovery SIMULATOR design Multidimensional MULTICOMPONENT and Multiphase System Surfactant Assisted Flooding orthogonal COLLOCATION Finite Difference Coherence Theory Hypothetical RESERVOIR NIGERIAN RESERVOIR
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Experimental Investigation of Laser Surface Hardening of AISI 4340 Steel Using Different Laser Scanning Patterns 被引量:1
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作者 Baha Tarchoun Abderrazak El Ouafi Ahmed Chebak 《Journal of Minerals and Materials Characterization and Engineering》 2020年第2期9-26,共18页
Laser surface transformation hardening becomes one of the most modern processes used to improve fatigue and wear properties of steel surfaces. In this process, the material properties and the heating parameters are th... Laser surface transformation hardening becomes one of the most modern processes used to improve fatigue and wear properties of steel surfaces. In this process, the material properties and the heating parameters are the factors that present the most significant effects on the hardened surface attributes. The control of these factors using predictive modeling approaches to achieve desired surface properties leads to conclusive results. However, when the dimensions of the surface to be treated are larger than the cross-section of the laser beam, various laser-scanning patterns are involved. This paper presents an experimental investigation of laser surface hardening of AISI 4340 steel using different laser scanning patterns. This investigation is based on a structured experimental design using the Taguchi method and improved statistical analysis tools. Experiments are carried out using a 3 kW Nd: YAG laser source in order to evaluate the effects of the heating parameters and patterns design parameters on the physical and geometrical characteristics of the hardened surface. Laser power, scanning speed and scanning patterns (linear, sinusoidal, triangular and trochoid) are the factors used to evaluate the hardened depth and the hardened width variations and to identify the possible relationship between these factors and the hardened zone attributes. Various statistical tools such as ANOVA, correlations analysis and response surfaces are applied in order to examine the effects of the experimental factors on the hardened surface characteristics. The results reveal that the scanning patterns do not modify the nature of the laser parameters’ effects on the hardened depth and the hardened width. But they can accentuate or reduce these effects depending on the type of the considered pattern. The results show also that the sinusoidal and the triangular patterns are relevant when a maximum hardened width with an acceptable hardened depth is desired. 展开更多
关键词 LASER Surface HARDENING Process experimental Investigation LASER Scanning PATTERNS AISI 4340 STEEL Hardness Profile Hardened Depth Hardened WIDTH design of Experiment Analysis of Variance
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Key design parameters and optimum method of medium- and high-velocity synchronous induction coilgun based on orthogonal experimental design 被引量:1
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作者 Kai-Pei Liu Xiao-Bo Niu +3 位作者 Ya-Dong Zhang Zeng-Chao Ji Jian-Yuan Feng Wen-Qi Li 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第2期202-209,共8页
The energy conversion efficiency of a multistage synchronous induction coilgun(MSSICG) has become one of the key factors that restricts its industrialization. To improve the launch efficiency of medium-and high-veloci... The energy conversion efficiency of a multistage synchronous induction coilgun(MSSICG) has become one of the key factors that restricts its industrialization. To improve the launch efficiency of medium-and high-velocity MSSICG,we propose an optimization design scheme combining orthogonal experimental design(OED) and self-consistent design method in this paper. The OED is introduced to reduce the number of iterations and improve the identification accuracy and efficiency. A self-consistent design model is established to overcome a defect that the parameters that need to be optimized will multiply as the number of coil stages increases. The influence of six factors(radial thickness of armature, axial length of armature, axial length of coil, capacitance, wire diameter, and slip speed) on the launch efficiency are then evaluated by range analysis. This work presents a valuable reference for optimizing medium-and high-velocity MSSICG. 展开更多
关键词 MULTISTAGE synchronous induction coilgun(MSSICG) SELF-CONSISTENT design orthogonal experimental design(OED) range analysis
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Characterization of Six Categories of Systematic 2<sup><i>n</i>-(<i>n</i>-<i>k</i>)</sup>Fractional Factorial Designs
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作者 Hisham Hilow 《Open Journal of Statistics》 2014年第1期75-88,共14页
Six categories of systematic 2n-(n-k) designs derivable from the full 2k factorial experiment by the interactions-main effects assignment are available for carrying out 2n-(n-k) factorial experiments sequentially run ... Six categories of systematic 2n-(n-k) designs derivable from the full 2k factorial experiment by the interactions-main effects assignment are available for carrying out 2n-(n-k) factorial experiments sequentially run after the other such that main effects are protected against the linear/quadratic time trend and/or such that the number of factor level changes (i.e. cost) between the runs is minimal. Three of these six categories are of resolution at least III and three are of resolution at least IV. The three categories of designs within each resolution are: 1) minimum cost 2n-(n-k) designs, 2) minimum cost linear trend free 2n-(n-k) designs and 3) minimum cost linear and quadratic trend free 2n-(n-k) designs. This paper characterizes these six categories and documents their differences with regard to either time trend resistance of factor effects and/or the number of factor level changes. The paper introduces the last category of systematic 2n-(n-k) designs (i.e. the sixth) for the purpose of extending the design resolution from III into IV and also for raising the level of protection of main effects from the linear time trend into the quadratic, where a catalog of minimum cost linear and quadratic trend free 2n-(n-k) designs (of resolution at least IV) will be proposed. The paper provides for each design in any of the six categories: 1) the sequence of its runs in minimum number of factor level changes 2) the defining relation or its 2n-(n-k) alias structure and 3) the k independent generators needed for sequencing the 2n-(n-k) runs by the generalized foldover scheme. A comparison among these six categories of designs reveals that when the polynomial degree of the time trend increases from linear into quadratic and/or when the design’s resolution increases from III to IV, the number of factor level changes between the 2n-(n-k) runs increases. Also as the number of factors (i.e. n) increases, the design’s resolution decreases. 展开更多
关键词 Sequential FACTORIAL Experimentation Trend Resistant Run ORDERS Generalized Fold-Over Scheme Interactions-Main Effects Assignment Cost of Factor Level Changes design Resolution
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拟康氏木霉液态发酵条件的研究 被引量:14
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作者 郝林华 牛德庆 +1 位作者 陈靠山 郭敏 《菌物学报》 CAS CSCD 北大核心 2005年第2期235-244,共10页
采用单因素和正交试验对筛选出的一株有潜力的生物防治菌——拟康氏木霉Trichoderma pseudokoningii的液态发酵条件进行优化,并进行100L发酵罐中试放大试验的研究。优化后的拟康氏木霉发酵控制参数为:培养基配方为麸皮40g/L,马铃薯50g/L... 采用单因素和正交试验对筛选出的一株有潜力的生物防治菌——拟康氏木霉Trichoderma pseudokoningii的液态发酵条件进行优化,并进行100L发酵罐中试放大试验的研究。优化后的拟康氏木霉发酵控制参数为:培养基配方为麸皮40g/L,马铃薯50g/L,蔗糖20g/L,KH2PO4 0.5 g/L,MgSO4·7H2O 0.5g/L,CaCl2 0.25g/L;摇瓶发酵培养时间为6d,培养基的初始pH值为6.0- 7.0,发酵温度为28±1℃。通过对拟康氏木霉生长曲线的测定,确定其在发酵罐中培养的时间60h为宜,此时所获得的菌丝体干重为1.2694g/100ml发酵液。本研究结果为高效率、低成本、工业化生产具有生防作用的拟康氏木霉菌丝制剂提供了科学依据。 展开更多
关键词 MgSO4 PH 线 40g 20g
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高速高稳定耐蚀性化学镀镍工艺的优化 被引量:1
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作者 李昕 杨昌英 +3 位作者 潘家荣 孙玉宝 张桂燕 王其龙 《三峡大学学报(自然科学版)》 CAS 2005年第2期171-174,共4页
在筛选出合适的化学镀镍的配位剂、稳定剂、加速剂等的基础上,运用正交实验法,以镀速、镀液稳定性及镀层耐腐蚀性为指标,确定了化学镀镍的配方及施镀工艺.结果表明,经过电化学前处理后,采用配方NiSO4·6H2O21.0g/L,NaH2PO2·H2O... 在筛选出合适的化学镀镍的配位剂、稳定剂、加速剂等的基础上,运用正交实验法,以镀速、镀液稳定性及镀层耐腐蚀性为指标,确定了化学镀镍的配方及施镀工艺.结果表明,经过电化学前处理后,采用配方NiSO4·6H2O21.0g/L,NaH2PO2·H2O25.4g/L,乳酸43.2g/L,甘氨酸6g/L,Cd2+2.5×10-3g/L,苹果酸4g/L,CH3COONa8g/L,十二烷基硫酸钠2.0×10-2g/L,pH=4.6~5.1,在90℃下施镀1.5h,镀速15.62μm/h,镀液稳定性125s,镀件耐腐蚀性大于43s. 展开更多
关键词 NAH2PO2 NiSO4 Cd^2%PLUS% 4g
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南瓜组培根根系分泌物的化感效应研究 被引量:32
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作者 李明 马永清 税军峰 《应用生态学报》 CAS CSCD 北大核心 2005年第4期744-749,共6页
使用组织培养技术、生物测试法及室内分析相结合的方法研究了南瓜组培根在不同生长时期与不同营养谐迫下(利用正交设计调节标准B5培养基中的大量元素、微量元素、有机质和激素)根分泌物对南瓜、萝卜和小麦3种受体的种子萌发及幼苗生长... 使用组织培养技术、生物测试法及室内分析相结合的方法研究了南瓜组培根在不同生长时期与不同营养谐迫下(利用正交设计调节标准B5培养基中的大量元素、微量元素、有机质和激素)根分泌物对南瓜、萝卜和小麦3种受体的种子萌发及幼苗生长的化感作用.结果表明,南瓜具有自毒作用,南瓜组培根根系分泌物对受体幼苗生长的抑制作用呈现出高抑低促的作用表型;南瓜组培根根系分泌物产生化感作用的活性与南瓜组培根生长速度有关,南瓜组培根根系分泌物的生长抑制活性以15~17d即生长速度指数末期为最高,2 1d生物量最大时的南瓜组培根根系分泌物的生长抑制活性最低;营养元素的改变明显影响了南瓜根系分泌物的产生,并通过筛选出能诱导南瓜组培根对受体具有强烈抑制作用的大量元素、微量元素、维生素和激素种类和含量的最优化组合,为研究南瓜化感作用营养胁迫机理提供依据. 展开更多
关键词
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Remediation of Heavy Metal (Cd, Cr, Cu, Co, and Ni) Ions from Kaolinite Clay Using Molecular Micelles Chelators and D-Optimum Experimental Design
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作者 Sayo O. Fakayode Ashley M. Taylor +4 位作者 Maya McCoy Sri Lanka Owen Whitney E. Stapleton Carmen Grady David A. Pollard 《Journal of Environmental Protection》 2013年第8期789-795,共7页
This study investigated the potential utility of poly (sodium N-undecanoyl-L-leucyl-valinate) (poly-L-SULV), poly (sodium N-undecanoyl-L-leucyl-alanate) (poly-L-SULA), and poly (sodium N-undecanoyl-glycinate) (poly-SU... This study investigated the potential utility of poly (sodium N-undecanoyl-L-leucyl-valinate) (poly-L-SULV), poly (sodium N-undecanoyl-L-leucyl-alanate) (poly-L-SULA), and poly (sodium N-undecanoyl-glycinate) (poly-SUG) molecular micelles (MMs) as chelators for heavy metal (Cd, Cr, Cu, Co, and Ni) ion remediation of kaolinite clay using D-optimum experimental design. D-optimum experimental design was employed to simultaneously investigate the influence of design variables such as the buffer pH, chelator concentration, and centrifuge speed to evaluate the optimum conditions and to reduce the time and cost of metal ion remediation. The partition coefficients of the metal ion concentrations between the kaolinite clay and chelator equilibrium were also evaluated. In addition, the influence of metal ion concentrations on the remediation capability of the chelators was evaluated by conducting remediation studies at four different (10 ppm, 40 ppm, 60 ppm, and 80 ppm) metal ion concentrations. In general, the results of the remediation efficiency and partition coefficients obtained in this study are highly metal ion dependent and also dependent upon the chelator used for the remediation. Specifically, the remediation efficiency of the molecular micelles was found to be comparable to or better than the corresponding remediation efficiency obtained when SDS or EDTA was used for the remediation. However, at optimum conditions, poly-SULV and poly-L-SULA molecular micelle chelators demonstrated superior remediation efficiencies for Cr, with remediation efficiency of 99.9 ± 8.7% and 99.1 ± 0.7%, respectively. 展开更多
关键词 Heavy Metal Ion REMEDIATION MOLECULAR Micelles Chelator D-Optimum experimental design KAOLINITE CLAY
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Optimal Designs Technique for Locating the Optimum of a Second Order Response Function
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作者 Idorenyin Etukudo 《American Journal of Operations Research》 2017年第5期263-271,共9页
A more efficient method of locating the optimum of a second order response function was of interest in this work. In order to do this, the principles of optimal designs of experiment is invoked and used for this purpo... A more efficient method of locating the optimum of a second order response function was of interest in this work. In order to do this, the principles of optimal designs of experiment is invoked and used for this purpose. At the end, it was discovered that the noticeable pitfall in response surface methodology (RSM) was circumvented by this method as the step length was obtained by taking the derivative of the response function rather than doing so by intuition or trial and error as is the case in RSM. A numerical illustration shows that this method is suitable for obtaining the desired optimizer in just one move which compares favourably with other known methods such as Newton-Raphson method which requires more than one iteration to reach the optimizer. 展开更多
关键词 Optimal designS of Experiment UNCONSTRAINED Optimization Response Surface Methodology Modified Super CONVERGENT Line Series Algorithm NEWTON-RAPHSON Method
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利用正交设计优化水曲柳ISSR-PCR反应体系 被引量:115
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作者 谢运海 夏德安 +1 位作者 姜静 林萍 《分子植物育种》 CAS CSCD 2005年第3期445-450,共6页
利用正交设计L16(45)对水曲柳ISSR-PCR反应体系的5因素(Taq酶,Mg2+,模板DNA,dNTP,引物)在4个水平上进行优化试验,PCR结果用统计软件MINITAB分析:①各因素的不同水平对PCR反应结果都有显著的影响,其中Taq酶量影响最大;②筛选出各反应因... 利用正交设计L16(45)对水曲柳ISSR-PCR反应体系的5因素(Taq酶,Mg2+,模板DNA,dNTP,引物)在4个水平上进行优化试验,PCR结果用统计软件MINITAB分析:①各因素的不同水平对PCR反应结果都有显著的影响,其中Taq酶量影响最大;②筛选出各反应因素的最佳水平,建立水曲柳ISSR-PCR反应的最佳体系(20滋l)为:Taq酶1.0U,Mg2+2.0mmol/L,模板DNA50 ̄200ng,dNTP0.15mmol/L,引物0.3滋mol/L。最后,对水曲柳ISSR-PCR最佳反应体系进行梯度退火,得到最佳退火温度为58.3℃。这一优化系统的建立为今后利用ISSR标记技术,研究水曲柳的地理变异提供一个标准化程序。 展开更多
关键词 PCR ISSR-PCR ISSR MINITAB MG^2%PLUS% Taq DNA DNTP 退 mol
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Orthogonal design to sift the optimal parameter of Neiguan acupuncture for cerebral infarction 被引量:7
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作者 Yanan Zhang Sha Yang +5 位作者 Xiaonong Fan Shu Wang Nina He Lingxin Li Ding Luo Xuemin Shi 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第28期2641-2648,共8页
The individual difference and non-repeatability in acupuncture have not only restricted the devel- opment of acupuncture, but have also affected the specificity of acupoints. The present study used instruments to cont... The individual difference and non-repeatability in acupuncture have not only restricted the devel- opment of acupuncture, but have also affected the specificity of acupoints. The present study used instruments to control needle depth, lifting and thrusting frequency, and the duration of acupuncture. Effects of the quantified acupuncture were observed at Neiguan (PC6) with different stimulation parameters. A frequency of 1, 2, or 3 Hz and duration of 5, 60, or 180 seconds were used to observe cerebral blood flow and ratio of infarct volume recovery. Results showed that stimulation at Neiguan with a frequency of 1 Hz and long duration of 180 seconds or 2/3 Hz and long duration of 5/60 seconds significantly increased cerebral blood flow and decreased the ratio of infarct volume. In- teractions between frequency and duration play a critical role in quantified acupuncture therapy. 展开更多
关键词 neural regeneration ACUPOINT quantified acupuncture NEIGUAN middle artery occlusion injury lift-ing and thrusting method orthogonal design lifting and thrusting frequency acupuncture duration grants-supported paper NEUROREGENERATION
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水库优化调度遗传算法参数的灵敏性分析 被引量:6
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作者 钟平安 唐林 《水力发电》 北大核心 2010年第11期13-16,共4页
选取选择算子、交叉算子、变异算子、初始种群数、交叉率、变异率和终止条件等7个主要因素,以搜索能力、时效性、收敛性、稳定性为算法性能评价指标,运用正交试验方法,进行遗传算法参数的多指标、多因素、多水平的模拟试验。采用极差分... 选取选择算子、交叉算子、变异算子、初始种群数、交叉率、变异率和终止条件等7个主要因素,以搜索能力、时效性、收敛性、稳定性为算法性能评价指标,运用正交试验方法,进行遗传算法参数的多指标、多因素、多水平的模拟试验。采用极差分析方法,确定因素对遗传算法性能影响,得到结论,遗传算法参数对各性能评价指标影响比模式的影响大;初始种群数、优值不变终止代数和变异率是影响算法综合性能的主要敏感参数。实例表明,采用确定式采样选择、均匀交叉和均匀变异模式遗传算法的综合性能较优。 展开更多
关键词 Optimal Operation Genetic Algorithm
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Application of quality by design in the current drug development 被引量:13
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作者 Lan Zhang Shirui Mao 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2017年第1期1-8,共8页
Quality by Test was the only way to guarantee quality of drug products before FDA launched current Good Manufacturing Practice. To clearly understand the manufacture processes, FDA generalized Quality by Design(QbD) i... Quality by Test was the only way to guarantee quality of drug products before FDA launched current Good Manufacturing Practice. To clearly understand the manufacture processes, FDA generalized Quality by Design(QbD) in the field of pharmacy, which is based on the thorough understanding of how materials and process parameters affect the quality profile of final products. The application of QbD in drug formulation and process design is based on a good understanding of the sources of variability and the manufacture process. In this paper,the basic knowledge of QbD, the elements of QbD, steps and tools for QbD implementation in pharmaceutics field, including risk assessment, design of experiment, and process analytical technology(PAT), are introduced briefly. Moreover, the concrete applications of QbD in various pharmaceutical related unit operations are summarized and presented. 展开更多
关键词 QUALITY by design(QbD) Process analytical technology(PAT) Critical QUALITY attributes(CQA) design of experiment(DoE) Risk assessment Near infrared(NIR)spectroscopy
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水稻强化栽培体系(SRI)优化配套技术探讨 被引量:16
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作者 俞爱英 吴增祺 +4 位作者 林贤青 朱贵平 周奶弟 陈冬莲 沈益民 《中国农学通报》 CSCD 2005年第7期162-164,共3页
以两优培九为试验材料,采用正交试验设计方法,研究了水稻强化栽培体系(SRI)秧龄、密度、施氮量等三因素三水平对两优培九产量及其构成因素的影响,建立高产的水稻强化栽培农艺措施的优化方案。试验结果表明,密度、施氮量、秧龄三因素对... 以两优培九为试验材料,采用正交试验设计方法,研究了水稻强化栽培体系(SRI)秧龄、密度、施氮量等三因素三水平对两优培九产量及其构成因素的影响,建立高产的水稻强化栽培农艺措施的优化方案。试验结果表明,密度、施氮量、秧龄三因素对产量影响均达极显著水平。水稻强化栽培体系(SRI)农艺优化措施是:15d秧龄移栽,密度为每公顷栽150000丛、施氮量为每公顷在30000kg绿肥作基肥的基础上,加化肥纯氮150kg。 展开更多
关键词 (SRI) 绿
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蛹虫草鲁山株C0511菌丝液体培养基筛选试验 被引量:4
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作者 宋越冬 Yue-dong 《河南农业科学》 CSCD 北大核心 2010年第12期107-110,共4页
液体培养蛹虫草鲁山菌株,以菌丝体产量为指标,对培养基的碳源、氮源、无机盐、维生素B1进行单因素试验,并在单因素基础上进行四因素三水平正交试验,结果表明:影响液体培养菌丝产量的主次因素依次为氮源、碳源、维生素B1和无机盐。最佳... 液体培养蛹虫草鲁山菌株,以菌丝体产量为指标,对培养基的碳源、氮源、无机盐、维生素B1进行单因素试验,并在单因素基础上进行四因素三水平正交试验,结果表明:影响液体培养菌丝产量的主次因素依次为氮源、碳源、维生素B1和无机盐。最佳培养基为:蔗糖20 g/L、蛋白胨25 g/L、维生素B10.15 g/L,无机盐为KH2PO41.5 g/L+MgSO40.5 g/L+CaCl20.25 g/L。 展开更多
关键词 CORDYCEPS militaris
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Optimization of Extraction Process of Fagopyri Dibotryis Rhizoma by Orthogonal Experiment
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作者 Jian YU 《Medicinal Plant》 2024年第3期26-29,共4页
[Objectives]To optimize the water extraction process of Fagopyri Dibotryis Rhizoma.[Methods]The entropy weight method was used to determine the weight of epicatechin extraction rate and dry extract rate and calculate ... [Objectives]To optimize the water extraction process of Fagopyri Dibotryis Rhizoma.[Methods]The entropy weight method was used to determine the weight of epicatechin extraction rate and dry extract rate and calculate the comprehensive score.The water extraction process of Fagopyri Dibotryis Rhizoma was optimized by orthogonal design with the comprehensive score as the indicator and the amount of water,extraction time and extraction times as the factors.[Results]The optimum extraction process of Fagopyri Dibotryis Rhizoma was as follows:adding 10 times of water,extracting 3 times,and extracting for 60 min each time.[Conclusions]The optimized extraction process is stable and feasible,and can be used for the extraction of Fagopyri Dibotryis Rhizoma. 展开更多
关键词 Fagopyri Dibotryis Rhizoma orthogonal EXPERIMENT EPICATECHIN DRY EXTRACT
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Optimization of rheological parameter for micro-bubble drilling fluids by multiple regression experimental design 被引量:2
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作者 郑力会 王金凤 +2 位作者 李潇鹏 张燕 李都 《Journal of Central South University》 SCIE EI CAS 2008年第S1期424-428,共5页
In order to optimize plastic viscosity of 18 mPa·s circulating micro-bubble drilling fluid formula,orthogonal and uniform experimental design methods were applied,and the plastic viscosities of 36 and 24 groups o... In order to optimize plastic viscosity of 18 mPa·s circulating micro-bubble drilling fluid formula,orthogonal and uniform experimental design methods were applied,and the plastic viscosities of 36 and 24 groups of agent were tested,respectively.It is found that these two experimental design methods show drawbacks,that is,the amount of agent is difficult to determine,and the results are not fully optimized.Therefore,multiple regression experimental method was used to design experimental formula.By randomly selecting arbitrary agent with the amount within the recommended range,17 groups of drilling fluid formula were designed,and the plastic viscosity of each experiment formula was measured.Set plastic viscosity as the objective function,through multiple regressions,then quadratic regression model is obtained,whose correlation coefficient meets the requirement.Set target values of plastic viscosity to be 18,20 and 22 mPa·s,respectively,with the trial method,5 drilling fluid formulas are obtained with accuracy of 0.000 3,0.000 1 and 0.000 3.Arbitrarily select target value of each of the two groups under the formula for experimental verification of drilling fluid,then the measurement errors between theoretical and tested plastic viscosity are less than 5%,confirming that regression model can be applied to optimizing the circulating of plastic-foam drilling fluid viscosity.In accordance with the precision of different formulations of drilling fluid for other constraints,the methods result in the optimization of the circulating micro-bubble drilling fluid parameters. 展开更多
关键词 orthogonal experimental design uniform experimental design CIRCULATING micro-bubbles plastic viscosity multiple regression experimental design
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Oxidative desulfurization of model and real oil samples using Mo supported on hierarchical alumina–silica: Process optimization by Box–Behnken experimental design 被引量:1
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作者 Nasim Ghorbani Gholamreza Moradi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第11期2759-2770,共12页
The catalytic performance of Mo supported on hierarchical alumina–silica(Si/Al = 15) with Mo loadings of 3, 6 and 15 wt% was investigated for the oxidative desulfurization(ODS) of model and real oil samples. Hierarch... The catalytic performance of Mo supported on hierarchical alumina–silica(Si/Al = 15) with Mo loadings of 3, 6 and 15 wt% was investigated for the oxidative desulfurization(ODS) of model and real oil samples. Hierarchical alumina–silica(h Al–Si) was synthesized by economical and ecofriendly silicate-1 seed-induced route using cetyltrimethylammonium bromide(CTAB) as mesoporogen. The effect of CTAB on the structure of catalyst was studied by characterization techniques. The results revealed that 6%Mo/h Al–Si had the highest sulfur removal compared to the other catalyst loadings. The effect of operating parameters was evaluated using Box–Behnken experimental design. The optimal desulfurization conditions with the 6%Mo/h Al–Si catalyst were determined at oxidation temperature of 67 ℃, oxidation time of 42 min, H2O2/S molar ratio of 8 and catalyst dosage of 0.008 g·ml^-1 for achieving a conversion of 95%. Under optimal conditions, different sulfur-containing compounds with initial concentration of 1000 ppm, Dibenzothiophene(DBT), Benzothiophene(BT) and Thiophen(Th), showed the catalytic oxidation reactivity in the order of DBT > BT>Th. According to the regeneration experiments, the 6%Mo/h Al–Si catalyst was reused 4 times with a little reduction in the performance. Also, the total sulfur content of gasoline and diesel after ODS process reached 156.6 and 4592.2 ppm, respectively. 展开更多
关键词 OXIDATIVE DESULFURIZATION HIERARCHICAL aluminasilica Silicate-1 seed-induced route BoxBehnken experimental design
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高师地理科学专业的GIS课程教学与实验设计 被引量:6
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作者 金宝石 《安庆师范学院学报(自然科学版)》 2010年第3期135-138,共4页
地理信息系统(GIS)是一门技术性、综合性很强的学科,作者在分析GIS课程的特点、内容和要求以及地理科学专业学生培养目标的基础上,指出二者之间存在的问题,根据自己在教学过程中的理论探讨和经验总结,设计了与课程相一致的实验教学方案... 地理信息系统(GIS)是一门技术性、综合性很强的学科,作者在分析GIS课程的特点、内容和要求以及地理科学专业学生培养目标的基础上,指出二者之间存在的问题,根据自己在教学过程中的理论探讨和经验总结,设计了与课程相一致的实验教学方案,进行理论与实验的一体化教学,可以在培养学生GIS技能的同时,促进学生对理论知识的理解和掌握,取得了较好的教学效果。 展开更多
关键词 GIS COLLEGE TEACHERS experimental design TEACHING
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