基于响应面法和NSGA-II算法的麦弗逊悬架优化     

李伟平  王世东  周兵  张利轩  马义超 《湖南农业大学学报(自然科学版)》2011,38(6):27-32

应用响应面法和经过改进的非支配排序遗传算法(NSGA-II)进行悬架结构参数优化.在ADAMS/Insight软件中进行设计参数的灵敏度分析，针对灵敏度较大的设计参数，建立车轮定位参数在车轮跳动过程中最大变化量的2阶响应面近似数学模型对该模型进行稳定性分析，并且应用加入精英保持策略和去除重复个体算法的NSGA-II优化算法对多目标响应面模型进行优化求解.优化结果表明该方法具有较高的精确性与有效性.  相似文献   

井渠灌区地下地表水耦合模拟及用水配置研究     

孙骁磊  田军仓  朱磊 《节水灌溉》2016,(11)

针对宁夏惠农区渠井用水比例失调,导致地下水越过适宜埋深造成次生盐渍化的问题。选择惠农区李岗村为试验区,在概化试验区水文地质条件,建立了水文地质概念模型,采用双重节点方式对地表水地下水模型进行耦合,在每个时间段对两者进行联立同时求解,通过HydroGeoSphere进行模型的计算求解,率定和验证模型中的水文地质参数。并通过建立的模拟模型,适时调整用水比例,得到在生态安全埋深下,渠井用水最优比例。  相似文献   

凸齿镇压器作业过程的运动学与动力学分析     

张智泓  张广凯  佟金  StephenCarr  赖庆辉  张兆国  方秋容 《安徽农业科学》2016,(5)

[目的]基于理论推导建立凸齿镇压器作业过程中的运动学和动力学模型。[方法]根据运动学中刚体做平面运动的瞬心定理和牵连运动为平动时质点的加速度合成定理,建立凸齿镇压器在不同工作阶段的运动参数模型;根据动力学中的动量定理、动能定理和冲量定理,建立凸齿镇压器工作状态中所需牵引力、凸齿与地面作用瞬间产生的冲击力和冲击能的参数模型。[结果]凸齿镇压器作业过程中所需的牵引力随着凸齿镇压器的自身质量和滚动阻力系数的增加而增大,而凸齿镇压器转动惯量的增加会降低凸齿镇压器所需牵引力;冲击过程中,凸齿镇压器的牵引速度越大、质量和转动惯量越大、冲击时间越短,则冲击力越大;凸齿镇压器冲击土壤时的冲击能随着凸齿的转动惯量、质量和质心竖直向下移动距离的提高而增加,而随土壤的弹性系数与土壤的塑性变形量的增加而减小。[结论]建立了凸齿镇压器在不同工作状态下运动学及动力学模型,分析并揭示了凸齿镇压器结构参数与运动参数间的相互联系,探索了凸齿镇压器冲击土壤的特征规律,为设计和优化其结构参数和运动参数提供了理论依据。  相似文献   

Practical use of response surface methodology for optimization of veterinary antibiotic removal using UV/H2O2 process     

《Aquacultural Engineering》2021

Three of the most commonly used veterinary antibiotics—enrofloxacin (ENR), sulfamethoxazole (SMX), and oxytetracycline (OTC)—were chosen as representative antibiotics for UV/H₂O₂ treatments. The objective was to determine the optimization of UV/H₂O₂ to remove antibiotics from aquaculture discharge water using response surface methodology. The degradation of the antibiotics was investigated under varying UV/H₂O₂ conditions in environments with different levels of pH, water matrices, humic acid, and constituent ions. The degradation results demonstrated that increasing the H₂O₂ dosage facilitated ENR degradation at a neutral pH while facilitating degradation of SMX and OTC at a slightly acidic pH. The optimum removal conditions for ENR, which was used in all influential effect experiments and the contact tank experiments, was obtained at 10 mM H₂O₂, a pretreated COD of 87.51 mg L⁻¹, and an initial pH of 6.15. Among the tested anions, only the presence of Cl^- showed slight positive effects on ENR degradation, due to the generation of secondary active radicals. During the reaction, the hydroxyl radical (OH) was present at a higher pH while singlet oxygen (¹O₂) was slightly present at a lower pH. The experimental results from H₂O₂ sequential addition indicated that freshly added H₂O₂ could quench the recently generated OH and therefore a high H₂O₂ concentration with frequent adding was not necessary. Our contact system reduced the ENR concentration in both the effluent reservoir and in the UV irradiation zone. The overall results supported the use of the UV/H₂O₂ system to treat remnant antibiotics in the discharge water.  相似文献   

地稔凝集素的提取及凝血活性的研究     

邓政东  程爱芳  李秀丽 《黑龙江农业科学》2015,(2):56-58

为研究和利用地稔的促凝血活性物质,以地稔为试材,提取地稔凝集素,研究pH、温度和糖等理化因素对凝血活性的影响。结果表明:经硫酸铵沉淀及透析提取的地稔凝集素具有红细胞凝集活性;碱性条件下,抑制作用明显,而酸性条件有较强促进作用;温度对凝集素凝血活性影响很小;半乳糖有明显促进作用。  相似文献   

Importance of Noncrystalline Hydroxide Phases in Sequential Extractions to Fractionate Antimony in Acid Soils     

《Communications in Soil Science and Plant Analysis》2012,43(11-12):1487-1501

Abstract

Sequential extraction techniques have been used to make inferences about speciation of phosphorus (P) and to a lesser extent arsenic (As) in soils. However, sequential extraction studies on the less‐abundant group V element, antimony (Sb), are limited. In this work, a widely used P sequential extraction scheme was modified and used to extract P, As, and Sb from two acidic soils from the Macleay River floodplain, NSW, that were enriched with Sb (26.9 and 23.0 mg kg^?1). An ammonium oxalate–oxalic acid step was included in the extraction sequence to dissolve the noncrystalline iron (Fe) and aluminium (Al) hydroxide phase. It extracted 30 to 47% of Sb, indicating the importance of this fraction, which may be mobilized in the floodplain by acid sulfate soil processes and periodic waterlogging. The original method overestimated P, As, and Sb in the residual fraction (30–71%). Relative efficiency values of extracts for P, As, and Sb were compared, and inferences about phase distributions were made. The results suggest some potential in using extractions to assess bioavailability of Sb in soil.  相似文献   

生物酶法提取中草药活性成分研究进展     

张艳  黄宝银  刘雪松  尹珺伊  唐伟  郝静友  史同瑞 《中国兽药杂志》2021,55(3):69-74

对酶提方法的原理、酶类选择依据、酶提工艺,以及酶提法应用现状进行了综述,旨在为同类研究提供技术参考。中草药具有广泛的应用前景和开发潜力,为提高中药疗效,方便临床用药,生产中常需要对中草药进行提取,然而传统的提取方法较为繁杂。随着科技进步,一些现代中药提取方法不断涌现。酶提方法是一种应用酶工程技术提取中药的现代中药提取方法,该方法具有高效、无毒、反应条件温和等优点,是一种发展潜力较大的中药提取方法。  相似文献   

分散固相萃取结合UPLC-Orbitrap MS联用测定鸡蛋中五氯苯酚残留量     

吴剑平  严凤  张婧  王博  潘娟  贡松松  达列亚.阿合买提 《中国兽药杂志》2021,55(4):20-29

建立了超高效液相色谱-静电轨道阱质谱联用测定禽蛋中五氯苯酚残留量的分析方法。取均质后的禽蛋样品经乙腈溶液提取,加入无水硫酸镁和氯化钠进行脱水和盐析,高速离心分层后,取适量乙腈层溶液经0.1%(V∶V)甲酸稀释后,用酸性氧化铝粉末进行样品净化并以10000 r/min离心取上清液,过0.22μm滤膜后上机测定。使用反相色谱柱进行分离,流动相为乙腈:0.1%甲酸=75∶25,采用等度程序进行洗脱,静电轨道阱质谱进行定性定量分析。结果表明,五氯苯酚在0.5~100μg/kg范围内线性关系良好(r>0.995),方法的最低检出限为0.2μg/kg,最低定量限为0.5μg/kg,添加回收率在74.43%~96.85%之间,批内批间变异系数CV%<10%。该方法具有较好的准确度与精密度,适用于禽蛋中五氯苯酚残留量的测定。  相似文献   

酸与碱处理对海带多糖提取及其抗氧化活性的影响     

陈文宁  郑娟霞  月金玲  杨莉  王琤韡 《中国饲料》2021,1(7):17-20

本试验采用柠檬酸提取法和碱提取法从海带中提取多糖组分,以总抗氧化能力和羟自由基（·OH）为衡量抗氧化活性指标,比较这两种提取方法得到海带粗多糖产率和抗氧化活性。试验结果表明：柠檬酸提取法和碱提取法的提取率分别为15.92%和6.05%,所提取的海带粗多糖具有良好的抗氧化活性,且柠檬酸提取法抗氧化活性更高。 [关键词] 柠檬酸提取法|碱提取法|海带多糖|抗氧化活性  相似文献   

响应面法优化沙棘再制奶酪加工工艺     

徐海祥  刘灵灵  陈籽达  李嘉晨 《中国乳业》2021,(9):106-115

本试验以新鲜沙棘果及奶酪为主要原料,探讨了沙棘再制奶酪的加工工艺。首先经护色、打浆、精磨、过滤、调酸、均质等工序,制备澄清均一的沙棘果汁。以样品感官品质和Vc含量为评价指标,通过单因素试验以及响应面试验,得出最佳配方及工艺为：35.00%天然奶酪、18.56%沙棘果汁（料水质量比1∶1）、1.54%复合乳化盐（m_柠檬酸钠∶m_{多聚磷酸钠}∶m_焦磷酸钠∶m_{六偏磷酸钠}=4∶2∶2∶1）、12.00%黄油、6.00%脱脂乳粉、6.00%白砂糖、0.50%复合稳定剂（m_卡拉胶∶m_黄原胶=4∶1）,其余20.40%为纯净水,乳化温度为84 ℃,乳化时间为11.4 min,搅拌速度为3 000 r/min。经此工艺制成的成品,感官评分为57.5分（满分60分）,Vc含量达16.61 mg/100 g。成品组织结构细腻光滑、色泽橘黄、口感润滑、营养丰富,具有沙棘果的风味,符合《GB25192—2010 再制奶酪》要求。  相似文献