ER_1110-2-1463(Engineering and Design - Hydrologic Engineering for Hydropower)(水力发电工程)
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化工进展Chemical Industry and Engineering Progress2024 年第 43 卷第 2 期单孔排气气泡特征识别与参数提取方法杨志龙1,田文斌1,张珍2,王志英3,王一伟3(1 中国农业大学工学院,北京 100083;2 石家庄铁道大学省部共建交通工程结构力学行为与系统安全国家重点实验室 石家庄 050043;3 中国科学院力学研究所流固耦合系统力学重点实验室,北京 100190)摘要:气液两相流广泛应用于多种工业领域当中,测量气泡特征参数并进行统计分析可以探究气泡的运动及生长规律,这对相关物理规律和过程控制研究具有重要意义。
然而气泡在运动中会发生融合、破碎等现象,导致图像中气泡的重叠粘连,以及拍摄背景的不均匀性均会对气泡特征数据提取造成较大误差。
本文采用高速摄像技术获得了不同液体流速与通气量下的气泡图像,通过对距离变换图像的极值点进行抑制与融合,改进了分水岭算法的前景标记提取方法,实现了气泡的准确分割,进而对分割气泡进行最小二乘椭圆拟合重构,获取了气泡参数。
对比分析发现,相较于腐蚀运算和阈值分割提取标记的方法,本文方法准确率分别提高了22.7%与13.6%。
通过对气泡特征进行统计分析,发现随着通气量的增加,气泡数量略微增多而平均尺寸显著增大,表明通气量对气泡尺寸有着重要影响。
通气量相同,随着来流速度的增加,气泡破碎,气泡的数量增加且平均尺寸减小。
关键词:气液两相流;重叠气泡识别;气泡特征统计;高速摄像中图分类号:O359 文献标志码:A 文章编号:1000-6613(2024)02-0808-10Geometric features recognition and parameters extraction of bubbles insingle-hole air bleedYANG Zhilong 1,TIAN Wenbin 1,ZHANG Zhen 2,WANG Zhiying 3,WANG Yiwei 3(1 College of Engineering, China Agricultural University, Beijing 100083, China; 2 State Key Laboratory of Mechanical Behavior in Traffic Engineering Structure and System Safety, Shijiazhuang Tiedao University, Shijiazhuang 050043, Hebei, China; 3 Key Laboratory for Mechanics in Fluid Coupling Systems, ChineseAcademy of Sciences, Beijing 100190, China)Abstract: Gas-liquid two-phase flow is prevalent in various industries. The measurement and statisticalanalysis of bubbles characteristics are useful for the investigation of the bubbles motion and generation. Therefore, it can provide the fundamental data for physical mechanism and process control research. In this paper, bubble images were captured by a high-speed camera system at different liquid flow rates and aeration volumes in the circulating water tank. Given that bubble coalescence and breakup during motion could lead to overlapping and sticking issues in the images, these phenomena would cause significantmeasurement errors in bubble characterization parameters. To address these issues, this paper improved the marker extraction method of the watershed algorithm. The method obtained foreground markers by utilizing the extreme points of the distance transformed image for suppression and fusion, thereby研究开发DOI :10.16085/j.issn.1000-6613.2023-1426收稿日期:2023-08-16;修改稿日期:2023-10-19。
2017年第36卷第10期 CHEMICAL INDUSTRY AND ENGINEERING PROGRESS·3697·化 工 进展基于3A 分子筛和TiO 2载体的钙基碳载体对污泥气化的影响张琪1,汪根宝2,李蒙2,张磊2,陈时熠1,向文国1(1东南大学能源热转换及其过程测控教育部重点实验室,江苏 南京 210009;2中国石化南京工程有限公司,江苏 南京211100)摘要:CaO 具有良好的CO 2吸收性能且对焦油裂解有促进作用,可实现污泥气化制取富氢气体,是无害化处理污泥的一种方式,具有较好的应用前景。
本文以3A 分子筛和TiO 2为载体,分别对CaO 进行改性,制取了CaO-3A 、CaO-TiO 2和CaO-TiO 2-3A 三种碳载体,研究了不同温度下其作为CO 2碳载体对污泥气化特性的影响。
实验结果表明:钙基碳载体和气化温度对污泥气化影响显著,添加碳载体以及提高气化温度均有利于提高H 2产量和污泥能量转换效率;CaO-TiO 2-3A 性能表现优越,气化温度650℃时,H 2浓度高达84.2%,碳转化率最高达46%;气化温度850℃时,H 2产量和能量转换率最高。
研究表明,CaO-TiO 2-3A 碳载体具有优越的污泥催化制氢性能。
关键词:污泥;气化;氧化钙;碳载体;废物处理中图分类号:X703 文献标志码:A 文章编号:1000–6613(2017)10–3697–07 DOI :10.16085/j.issn.1000-6613.2017-0238Effects of 3A molecular sieve and TiO 2 supported CaO on the gasificationof sewage sludgeZHANG Qi 1,WANG Genbao 2,LI Meng 2,ZHANG Lei 2,CHEN Shiyi 1,XIANG Wenguo 1(1 Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education ,Southeast University ,Nanjing210009,Jiangsu ,China ;2 SINOPEC Nanjing Engineering Co.,Ltd.,Nanjing 211100,Jiangsu ,China )Abstract :CaO can be used to absorb CO 2 and to promote the tar cracking in sludge gasification to produce hydrogen-rich gases. Gasification of CaO-sewage sludge is a promising alternative technology to use sewage sludge and to reduce the secondary pollutions. In this work ,3A molecular sieve and TiO 2 were used as the supports to modify CaO. Three CO 2 sorbents were prepared :CaO-3A molecular sieve ,CaO-TiO 2,and CaO-TiO 2-3A molecular sieve. The effects of modified CaO as the CO 2 sorbents on the gasification of sewage sludge in a fixed bed reactor were studied at different temperatures. The experimental results showed that the increase of gasification temperature and the addition of the CO 2 sorbents could both promote the H 2 production and energy conversion rate. Among the three modified CaO CO 2 sorbents ,CaO-TiO 2-3A exhibited the highest H 2 yield and energy conversion rate. With the CaO-TiO 2-3A sorbent ,the concentration of H 2 reached 84.2% and the carbon conversion rate was 46% at 650℃. The experiments results showed that CaO-TiO 2-3A appeared to have the best adsorption and hydrogen production performances.Key words :sewage sludge ;gasification ;calcium oxide ;absorbents ;waste treatment作为污水处理厂的附属产物,城市污泥的产量增长迅速,如何有效而又环保地处理污泥引起了全球学者的广泛关注。
第45卷第3期2023年5月沈 阳 工 业 大 学 学 报JournalofShenyangUniversityofTechnologyVol 45No 3May2023收稿日期:2022-01-28.基金项目:辽宁省沈阳材料科学国家研究中心联合研发基金项目(2019JH3/30100019).作者简介:李志杰(1963-),男,辽宁沈阳人,教授,博士,主要从事纳米材料制备、应用及磁性材料等方面的研究.doi:10.7688/j.issn.1000-1646.2023.03.08磁性FeNi@C/Cu纳米颗粒制备及除油应用李志杰,王福春,王馨月,张超超,刘泰奇(沈阳工业大学理学院,沈阳110870)摘 要:为了处理港口码头薄油膜污染,在氩/氢气氛下利用电弧法制备Fe0 64Ni0 36为主相的合金纳米产物,采用水热法和高温碳化法制备碳包覆的核壳磁性FeNi@C/Cu复合纳米颗粒.对合金粒子以及碳包覆后的复合纳米颗粒进行表征及性能检测.结果表明:FeNi合金纳米粒子呈球状,500℃下制得的粒子饱和磁化强度最高,可以达到101 09A·m2/kg,比常温下制备的粒子提升16 0%.利用FeNi@C/Cu复合纳米颗粒对煤油、柴油与机油的除油能力分别为3 18、3 43和3 46g/g,表明FeNi@C/Cu复合纳米颗粒具有良好除油性能.关 键 词:FeNi合金纳米粒子;FeNi@C/Cu复合纳米颗粒;电弧法;磁性能;水热法;高温碳化法;包覆;除油中图分类号:TM271 文献标志码:A 文章编号:1000-1646(2023)03-0284-07PreparationanddegreasingapplicationofmagneticFeNi@C/CunanoparticlesLIZhi jie,WANGFu chun,WANGXin yue,ZHANGChao chao,LIUTai qi(SchoolofScience,ShenyangUniversityofTechnology,Shenyang110870,China)Abstract:Inordertodealwiththepollutionofthethinoilfilmofportterminal,anelectricarcmethodwasusedtopreparealloynanopowderproductswithFe0 64Ni0 36asthemainphaseinanargon/hydrogenatmosphere.Thecore shellmagneticFeNi@C/Cucompositenanoparticleswerepreparedbyhydrothermalandhightemperaturecarbonizationmethods.Alloyparticlesandcarbon coatedcompositenanoparticleswerecharacterizedandtheirpropertiesweretested.TheresultsshowthatFeNialloynanoparticlesareofsphericalshape.Thesaturatedmagnetizationvalueofthenanoparticlespreparedat500℃isofthehighestvalue,reaching101 09A·m2/kg,whichincreasesby16 0%comparedwiththatpreparedatroomtemperature.TheFeNi@C/Cucompositenanoparticlesaretestedfortheadsorptionofkerosene,dieselandengineoil,andtheadsorptioncapacitiesare3 18g/g,3 43g/gand3 46g/g,respectively,indicatingthattheFeNi@C/Cucompositenanoparticleshavegooddegreasingperformance.Keywords:FeNialloynanoparticle;FeNi@C/Cucompositenanoparticle;electricarcmethod;magneticproperty;hydrothermalmethod;hightemperaturecarbonizationmethod;coating;degreasing 随着全球经济化的不断发展进步,海运作为世界贸易运输中最有效、也是最安全的运输方式,承担了世界远程运送大宗货物总量近90%的运送任务[1].各类船舶在港口、码头装卸以及清洗机器过程中会产生煤油、柴油、机油等轻油污染,并在近海岸海面上形成薄油膜.油膜和海水混成一体,气味难闻,且挥发速率极低,会对水中生物产生恶劣影响[2].油膜可直接通过皮肤黏膜接触和呼吸等途径侵入人体,若油膜粘附鸟类羽毛则会影响其正常觅食[3];油膜若由土壤渗入到地下则会污染地下水质,威胁人类健康[4].因此,开发出具有亲油性良好、密度小、无毒可回收的材料去Copyright ©博看网. All Rights Reserved.处理港口码头薄油膜污染问题已经刻不容缓.FeNi合金纳米粉体具有较好的物理特性和较高的化学稳定性,在磁性[5]、吸波[6]和催化性能[7]等方面受到广泛关注.利用具有高磁性的FeNi合金纳米粉体进行海面油污处理将更利于磁场捕集.然而,合金粒子本身密度大且对油的吸附能力不强,为了降低粒子密度并提高纳米粉体对油的吸附性能,通过无机或有机材料[8]对粉体表面修饰并形成核壳型结构纳米粒子是一种有效途径.Li等[9]利用葡萄糖、硝酸铜和Fe3O4纳米颗粒合成了Fe3O4@C@Cu2O复合颗粒,用于去除水中污染物.Abdelwahab等[10]利用葡萄糖、聚苯胺等试剂,采用乳液聚合法制备出具有良好亲水性和分散性的核壳结构PANI/Fe3O4/C纳米复合材料,且能够达到去除海面柴油的目的.通过葡萄糖提供碳源实现碳包覆磁性材料,体现出碳壳的高稳定性,能够更好屏蔽偶极子相互作用并促进其与金属离子之间的相互作用[2],同时碳壳易于引入含氧官能团,对吸油性能的提升起到良好的增益效果.Liu[11]利用葡萄糖、碱式碳酸铜包覆Fe3O4制备Fe3O4@C/Cu复合材料用于处理水面浮油,采用葡萄糖提供碳源可做到漂浮处理水面浮油且无二次污染,但以Fe3O4作为内核材料磁性能较低,不利于更好的回收.基于核壳结构磁性复合纳米粒子的优异性能,选择具有高饱和磁化强度的FeNi合金作为内核,可以有效提高包覆后吸油颗粒的饱和磁化强度,更好地提高颗粒的磁性回收.本文在氩气、氢气混合气氛下利用电弧法制备出颗粒均匀的FeNi合金纳米粒子,并探究不同温度下制得纳米粒子的磁性能;采用水热法和高温碳化法并以葡萄糖提供碳源,选用碱式碳酸铜为催化剂,制备包覆碳层的核壳磁性FeNi@C/Cu复合纳米颗粒,所得纳米颗粒具有密度小、磁性强、无二次污染、除油性能优异等特性,可用作清理水面浮油.1 材料与方法1 1 试验原料与设备试验原料包括Fe棒(纯度99 9%)、Ni棒(纯度99 9%)、氢气(纯度99 99%)、氩气(纯度99 99%)、钨棒(99 99%)、去离子水、葡萄糖(C6H12O6)、乙醇(C2H5OH)、柠檬酸(C6H8O7)、司班 60(C24H46O6)、碳酸铜(CuCO3·Cu(OH)2·H2O)和正硅酸乙酯(TEOS)等.主要试验设备包括真空熔炼设备(VSD 450)、电弧等离子体粉体制备装置(VZD 400)、搅拌器(JJ 1B)、水浴锅(HH 1)、真空干燥箱(DZF 6050)、管式烧结炉(SG GL1400)、X射线衍射仪(MiniFlex600)、拉曼光谱分析仪(JobinYvonLabRamHR800)、傅里叶变换光谱仪(IR prestige21)、热场扫描电镜(GeminiSEM300)、透射电子显微镜(EITecnaiG2F30)和振动样品磁强计(BKT 4500Z)等.1 2 样品制备1 2 1 FeNi合金纳米粉体制备将Fe棒、Ni棒按照1∶1原子比于纯氩气状态下熔炼成总质量为25g的FeNi合金锭.将熔炼后的合金块体经抛光去除表面氧化膜后放于电弧设备铜底座上作为阳极,将钨棒作为阴极.将电弧设备工作腔抽至一定真空态,通入反应气体氩气和氢气,控制工作腔内加热套升温至指定温度,启动电弧电源开始起弧.起弧后调节电流并调整钨针位置直至弧形平稳.起弧完成后关闭加热套升温系统,静置2h后将腔体重新充入氩气和少量氧气进行钝化,反应12h后收集钝化后的纳米粉体产物.1 2 2 FeNi@C/Cu复合纳米粉体制备在60℃水浴加热条件下将浓度为0 1mol/L的柠檬酸溶液置于烧杯中,称取定量FeNi合金纳米粉体放入溶液后,在60℃水浴加热条件下搅拌10min.此外,制备一定量的饱和葡萄糖溶液并倒入上述烧杯中,水浴加热搅拌10min.再称取一定量的司班 60和碱式碳酸铜分别作为分散剂和催化剂放入上述复合溶液中并搅拌2h.取出样品后真空干燥,研磨大颗粒并利用150目筛网进行过滤.将过滤后的粉末在450℃管式炉中进行加热,加热时需要通入氮气保护气体.将烧结后的粉末样品研磨后利用蒸馏水和乙醇清洗数遍,干燥后即可得到最终粉末样品.2 结果与分析2 1 FeNi合金纳米粒子的表征图1为在不同温度条件下制得的样品粉体的XRD图谱.图1a中40°~80°范围内存在三个明显衍射峰,峰强度较高且峰形较平滑,说明产物结晶度较高.利用Scherrer公式计算晶粒尺寸约为36nm.对照PDF卡片,发现衍射峰与Fe0 64Ni0 36(PDF#47 1405)相符,呈面心立方结构,衍射峰在43 74°、50 90°和74 90°处可以分别指化为Fe0 64Ni0 36的(111)、(200)和(220)晶面衍射峰.由图1b可知,582第3期 李志杰,等:磁性FeNi@C/Cu纳米颗粒制备及除油应用Copyright ©博看网. All Rights Reserved.当加热温度为300℃和500℃时,衍射峰位置未改变,但峰型存在宽化现象,说明颗粒样品平均粒径逐渐减小[12],利用Scherrer公式计算可知,随着反应温度的升高(常温到500℃),晶粒尺寸分别为30 7、28 5、17 4nm,这与由分析图谱得到的结论相符.当反应温度为800℃时,图谱中除了具有Fe0 64Ni0 36衍射峰外,在44 83°、65 18°和82 35°附近还存在其他物相的衍射峰,经过对比发现另外三个衍射峰与体心立方结构FeNi(PDF#031049)的(110)、(200)和(211)晶面衍射峰相吻合,说明800℃下电弧产生的合金样品形成了新的合金相.图1 FeNi合金纳米粒子的XRD图谱Fig 1 XRDspectraofFeNialloynanoparticles图2为常温条件下制得的FeNi合金纳米粒子的SEM图像.由图2可见,样品中少数颗粒粒径较大,其余颗粒尺寸约为20~50nm,粒径均匀,呈球状.纳米颗粒独有的尺寸效应以及FeNi合金颗粒的高饱和磁化强度促使粒子间相互吸附形成如图2所示的链状结构.2 2 FeNi合金纳米粒子的磁性能图3为不同温度条件下制备得到的FeNi合金纳米粒子的VSM图.常温下样品饱和磁化强度M为87 18A·m2/kg.当温度升至300℃时,饱图2 FeNi合金纳米粒子的SEM图像Fig 2 SEMimageofFeNialloynanoparticles和磁化强度增至95 68A·m2/kg,500℃时饱和磁化强度达到最高值101 09A·m2/kg,涨幅分别为9 7%和16 0%.由图1b可知,(200)晶面衍射峰为易磁化峰,当温度升高时,样品产物衍射峰强度降低,通过计算可知,(200)与(111)晶面衍射强度比值增大,说明升高一定温度后粉体饱和磁化强度增大.当加热到800℃时,饱和磁化强度降低至70 35A·m2/kg,降幅约为19 3%,这是由于样品中析出了FeNi合金相,促使样品富Fe合金中的Fe0 64Ni0 36合金相一部分转化成FeNi合金相,Fe含量减少[13],同时说明合金相结构的改变会改变合金性能[14].常温下制得样品的矫顽力H为3 08A/m,300℃与500℃下制得的纳米粒子矫顽力分别降低为2 56、2 85A/m,800℃下制得的纳米粒子矫顽力增大到3 40A/m,因为材料的矫顽力与其晶粒大小和饱和磁化强度有关,其变化遵循1/(MsD)规律[12],结合XRD中计算出的不同温度FeNi合金的粒径大小以及饱和磁化强度数据可以发现,合金的晶粒大小相差不大,在300℃与500℃条件下制得的纳米合金粉末的饱和磁化强度增大明显,因此,样品的矫顽力下降明显,在800℃制得样品的矫顽力产生增大现象.可见,温度对纳米粒子磁性能具有很大影响.图3 FeNi合金纳米粒子的VSM图Fig 3 VSMdiagramofFeNialloynanoparticles682沈 阳 工 业 大 学 学 报 第45卷Copyright ©博看网. All Rights Reserved.2 3 FeNi@C/Cu复合纳米颗粒的性能表征利用X射线衍射仪对FeNi与FeNi@C/Cu复合纳米颗粒进行物相分析,结果如图4所示.对比碳包覆与未包覆纳米颗粒的衍射峰强度可知,包覆后衍射峰变弱,表明随着非晶体数量的增加,晶体化程度呈现降低趋势[15].将15°~35°区间衍射峰图放大后发现,FeNi@C/Cu样品在20°~30°区间存在不定型石墨波,说明FeNi@C/Cu复合纳米颗粒被无定型碳层包覆[2].(111)、(200)、(220)等晶面处衍射峰的位置未改变,也未发现其他衍射峰,说明无定型碳层对样品粒子晶型影响较小,样品仍然为面心立方晶相.由于样品中铜含量较少,故未发现铜峰,也未检测出氧化物或碳化物的衍射峰,说明测试样品晶体成分单一,不存在其他杂相.图4 FeNi与FeNi@C/Cu复合纳米颗粒的XRD图谱Fig 4 XRDspectraofFeNiandFeNi@C/Cucompositenanoparticles图5为FeNi@C/Cu复合纳米颗粒的SEM和TEM图像.由图5a可见,FeNi@C/Cu复合纳米颗粒具有良好的分散性和均匀分布的粒径并呈现近似球体形态,与包覆前差距不大,一些小颗粒为在葡萄糖碳化后附着于FeNi@C/Cu复合纳米颗粒表面的司班 60或碳聚合物[2].图5a中包覆后颗粒表面粗糙,会增加吸油效率,有利于样品除油应用.由图5b可见,内核颗粒颜色较深的物质为FeNi合金纳米粒子,其核心晶格间距为0 177nm,与Fe0 64Ni0 36(PDF#47 1405)面间距一致.外层颜色较浅的物质为厚约10nm的碳层,可见碳呈非晶态.图6为FeNi@C/Cu复合纳米颗粒的拉曼光谱.ID/IG值(峰强比)越小,碳有序度越高[16].FeNi@C/Cu复合纳米颗粒具有两个明显特征峰,D峰位于1365 7cm-1处,具有高强度和大宽度,图5 FeNi@C/Cu复合纳米颗粒的SEM和TEM图像Fig 5 SEMandTEMimagesofFeNi@C/Cucompositenanoparticles这归因于石墨原子层中质量畸变引起的声子约束效应[11].另一个峰位于1591 1cm-1处,可以归因于弯曲石墨层的应变和不均匀性,也说明颗粒表面含有大量C—C、C==C和C≡≡C键,这些官能团对油的吸附起到促进效果[2].通过拉曼光谱计算可知,ID/IG为0 858(小于1),说明产物中的碳相对有序.图6 FeNi@C/Cu复合纳米颗粒的拉曼光谱Fig 6 RamanspectrumofFeNi@C/Cucompositenanoparticles图7为FeNi与FeNi@C/Cu复合纳米颗粒的傅里叶红外光谱.FeNi合金纳米粒子在1637cm-1与3437cm-1处具有两个明显的衍射峰.FeNi@C/Cu复合纳米颗粒在2358cm-1处具有振动峰,这是782第3期 李志杰,等:磁性FeNi@C/Cu纳米颗粒制备及除油应用Copyright ©博看网. All Rights Reserved.由C≡≡C键的振动引起的,说明FeNi合金纳米颗粒表面在经过高温处理时存在利于碳化的官能团,这主要是受到炔烃中氢原子的影响,在高温处理过程中金属取代炔中活泼的氢原子并以新的炔化物形式存在[17].FeNi@C/Cu复合纳米颗粒在1513cm-1处的衍射峰对应C==C键的振动,说明葡萄糖发生碳化.1024cm-1附近衍射峰的形成归因于一些醇的残留[11].图7 FeNi与FeNi@C/Cu复合纳米颗粒的FTIR光谱Fig 7 FTIRspectraofFeNiandFeNi@C/Cucompositenanoparticles2 4 FeNi@C/Cu复合纳米颗粒的磁性能选取具有高饱和磁化强度的样品进行包覆试验,对复合颗粒进行磁性能测试,结果如图8所示.由图8可见,粉体磁性能下降,常温下制得样品的饱和磁化强度下降至69 24A·m2/kg,为包覆前的79 42%.500℃下制得的FeNi纳米粒子包覆后饱和磁化强度下降至67 79A·m2/kg,这是由无定形碳壳的单位质量能够提供较小的磁力矩造成的[11].常温下制得的FeNi@C/Cu复合纳米颗粒剩磁从8 48A·m2/kg降至6 01A·m2/kg,仅下降了29 1%,表明复合纳米颗粒仍然具有强烈的磁响应.内禀矫顽力从3 08A/m降低到2 41A/m,表明复合纳米颗粒的各向异性在制备过程中有所削减.此外,500℃下制得的FeNi纳米粒子内禀矫顽力从285A/m降低到2 40A/m.磁性会直接影响纳米粒子的除油性能,磁性纳米粒子与油滴粒子具有一定絮凝力,矫顽力与高饱和磁化强度使得复合纳米颗粒周围磁场呈阶梯形式快速升高[2],从而对油滴分子的磁力作用有所提高,因而更有助于对油分子进行吸附.不同温度条件下制得的FeNi合金纳米粒子在碳包覆后得到的复合纳米颗粒磁性无太大差别,均具有良好的除油性能.图8 FeNi@C/Cu复合纳米颗粒的VSM图Fig 8 VSMdiagramofFeNi@C/Cucompositenanoparticles3 FeNi@C/Cu复合纳米颗粒的除油应用 为了探究样品漂浮性与磁性回收情况,将FeNi@C/Cu复合纳米颗粒放置于水面上,利用玻璃棒搅拌后采用钕铁硼块体吸附颗粒,结果如图9所示.首先利用表面皿盛装适量水,将FeNi@C/Cu复合纳米颗粒撒在水面上,颗粒在水面分散性能较好,且颗粒能漂浮于水面.之后利用玻璃棒搅拌,样品不下沉且未粘连玻璃棒,说明FeNi@C/Cu复合纳米颗粒表面能很低,利于其吸附油污.然后将钕铁硼块体置于表面皿一侧,复合纳米颗粒很快被吸附聚集,水面澄清且不残留粉体,说明FeNi@C/Cu复合纳米颗粒磁性强,具有很强的磁响应.图9 FeNi@C/Cu复合纳米颗粒水面静置与回收Fig 9 RestingandrecoveryofFeNi@C/Cucompositenanoparticlesonwatersurface882沈 阳 工 业 大 学 学 报 第45卷Copyright ©博看网. All Rights Reserved.为了便于观察,将选取的柴油、煤油、机油等试验油品利用苏丹Ⅲ染色,其中FeNi@C/Cu复合纳米颗粒吸附柴油过程如图10所示.先将一定量染色柴油滴于水面(见图10a),添加一定量的除油颗粒后,油层会被快速打散并分成碎片(见图10b),同时柴油逐渐聚集在颗粒周围并被颗粒迅速吸收.将钕铁硼块体置于表面皿一侧时,吸附了柴油的磁性颗粒迅速聚集在块体周围(见图10c).最后,将钕铁硼块体与吸附柴油的颗粒收集,可以得到清澈水面(见图10d).在油吸附测量试验中,将0 7g柴油和0 2g吸油颗粒放入水中,除油率为98%,柴油吸附效率为3 43g/g.在相同条件下,煤油和机油的吸附效率(除油能力)分别为3 18g/g和3 46g/g.这些结果表明FeNi@C/Cu复合纳米颗粒具有良好的除油性能.图10 FeNi@C/Cu复合纳米颗粒的除油过程Fig 10 DegreasingprocessofFeNi@C/Cucompositenanoparticles4 结 论采用水热法和高温碳化法,利用葡萄糖包覆FeNi合金纳米粒子,制备得到用于处理水面薄油膜的新型材料FeNi@C/Cu复合纳米颗粒.利用电弧法制备的FeNi合金纳米粒子500℃下饱和磁化强度最高值为101 09A·m2/kg.采用葡萄糖包覆得到的核壳结构FeNi@C/Cu复合纳米颗粒具有良好的磁性能,利于吸油后粉体的回收.由于复合颗粒密度小能够漂浮于水面,可有效处理水面薄油层.利用复合颗粒对煤油、柴油和机油进行吸油试验,除油能力分别为3 18、3 43和3 46g/g,吸附性强且吸油速度较快.因此,FeNi@C/Cu复合纳米颗粒可以有效去除水面薄油膜,有望在港口或其他海洋环境中发挥重要作用.参考文献(References):[1]智峤生.海上能源运输对全球航运市场的影响[J].中国储运,2021(10):196-197.(ZHIQiao sheng.Influenceofmaritimeenergytrans portationonglobalshippingmarket[J].ChinaStorage&Transport,2021(10):196-197.)[2]刘泰奇.用于海面除油的碳包覆磁性漂浮纳米颗粒的应用研究[D].沈阳:沈阳工业大学,2019.(LIUTai qi.Applicationresearchofcarbon coatedmagneticfloatingnanoparticlesforseasurfacedeoiling[D].Shenyang:ShenyangUniversityofTechnology,2019.)[3]周亚蕊.海带质基光催化剂的制备及其吸附降解海面油污性能研究[D].舟山:浙江海洋大学,2019.(ZHOUYa rui.Preparationofseaweed basedphoto catalystsanditsadsorptionandphotodegradationabili tyonseasurfaceoil[D].Zhoushan:ZhejiangOceanUniversity,2019.)[4]郭峰.石油污染治理技术综述[J].化工管理,2021(19):51-53.(GUOFeng.Reviewofoilpollutioncontroltechnolo gy[J].ChemicalEnterpriseManagement,2021(19):51-53.)[5]SrakaewN.StructuralandmagneticpropertiesofFexNi100 xalloyssynthesizedusingAlasareducingmetal[J].JournalofMagnetismandMagneticMate rials,2017,435:201-205.[6]Almasi KashiM,MokarianMH,Alikhanzadeh AraniS.Improvementofthemicrowaveabsorptionproper tiesinFeNi/PANInanocompositesfabricatedwithdif ferentstructures[J].JournalofAlloysandCom pounds,2018,742:413-420.[7]钟爱华.镍铁核壳结构纳米催化剂的制备及其催化氨分解的性能研究[D].南京:南京大学,2018.(ZHONGAi hua.Synthesisofnickel,ironandtheiralloyscatalystsandtheirapplicationinammoniade composition[D].Nanjing:NanjingUniversity,2018.)[8]汤骏.用于液—液非均相反应的磁性纳米界面催化剂的制备与调控[D].杭州:浙江工业大学,2019.(TANGJun.Magneticpickeringinterfacialcatalyst:design,synthesisandapplicationinliquid liquidbi phasicreaction[D].Hangzhou:ZhejiangUniversityofTechnology,2019.)[9]LiSK,HuangFZ,WangY,etal.MagneticFe3O4@C@Cu2Ocompositeswithbean likecore/shellnano structures:synthesis,propertiesandapplicationinre cyclablephotocatalyticdegradationofdyepollutants[J].JournalofMaterialsChemistry,2011,21(20):7459-7466.[10]AbdelwahabNA,El GhaffarM.Preparationandcharacterizationofhighlyhydrophobicmagneticpoly anilinenanocompositeforfastandefficientseparationofdieseloilfromseawater[J].MaterialsResearchBulletin,2016,84:7-14.[11]LiuTQ.FacilepreparationofFe3O4@C/Cucore shellsub micronmaterialsforoilremovalfromwatersurface[J].AppliedSurfaceScience,2019,466:483-489.982第3期 李志杰,等:磁性FeNi@C/Cu纳米颗粒制备及除油应用Copyright ©博看网. 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All Rights Reserved.。
第42卷第1期自动化学报Vol.42,No.1 2016年1月ACTA AUTOMATICA SINICA January,2016基于表面肌电的运动意图识别方法研究及应用综述丁其川1熊安斌1赵新刚1韩建达1摘要表面肌电信号(Surface electromyography,sEMG)是人体自身的资源,蕴含着关联人体运动的丰富信息,用它作为交互媒介以构建人机交互(Human-robot interaction,HRI)系统有天然的优势.通过肌电信号实现人机自然交互的关键是由肌电信号识别出人体运动意图,通常包括离散动作模态分类、关节连续运动量估计及关节刚度/阻抗估计等三方面内容.本文详细归纳基于表面肌电的运动识别方法研究成果,总结当前研究的特点;随后,介绍基于表面肌电的运动识别技术的应用现状,并探讨制约其推广的主要问题;最后,展望该技术的未来发展.关键词表面肌电信号,人机交互,运动识别,刚度估计,自然控制引用格式丁其川,熊安斌,赵新刚,韩建达.基于表面肌电的运动意图识别方法研究及应用综述.自动化学报,2016,42(1): 13−25DOI10.16383/j.aas.2016.c140563A Review on Researches and Applications of sEMG-based MotionIntent Recognition MethodsDING Qi-Chuan1XIONG An-Bin1ZHAO Xin-Gang1HAN Jian-Da1Abstract Surface electromyography(sEMG)signals are human s own resources,which contain a wealth of information associated with one s movement.Thus,there is a natural advantage in utilizing sEMG signals as interface media to construct human-robot interaction(HRI)systems.The key to realize a natural HRI with sEMG is recognizing human s motion intention from sEMG signals,which usually involves three aspects,i.e.,classifying discrete motion modes,esti-mating continuous movements of joints,and estimating stiffness or impedance of joints.This paper fully collects the researches on methods of sEMG-based motion recognition,and summarizes the features of current studies.Afterwards, this paper introduces the application status of sEMG-based motion recognition technology,and discusses the key issues constraining its marketing applications.Finally,future development of the technology is presented.Key words Surface electromyography(sEMG),human-robot interaction(HRI),motion recognition,stiffness estimation, natural controlCitation Ding Qi-Chuan,Xiong An-Bin,Zhao Xin-Gang,Han Jian-Da.A review on researches and applications of sEMG-based motion intent recognition methods.Acta Automatica Sinica,2016,42(1):13−25机器人技术发展正强劲推动着机器人的应用由工业生产领域延伸到军事、医疗、服务等领域,在未来社会,人类同机器人的交流甚至彼此身体的直接结合将日益频繁,作为连接人与机器人信息通道的人机交互技术必将在人类生活中扮演至关重要的角色[1].传统基于程式控制的人机交互方式桎梏了机收稿日期2014-08-04录用日期2015-10-10Manuscript received August4,2014;accepted October10,2015国家高技术研究发展计划(863计划)(2015AA042301),国家自然科学基金(61273355,61503374,61573340),机器人学国家重点实验室自主课题(2015-z06)资助Supported by National High Technology Research and De-velopment Program of China(863Program)(2015AA042301), National Natural Science Foundation of China(61273355, 61503374,61573340),and Self-planned Project of the State Key Laboratory of Robotics(2015-z06)本文责任编委王聪Recommended by Associate Editor WANG Cong1.中国科学院沈阳自动化研究所机器人学国家重点实验室沈阳1100161.State Key Laboratory of Robotics,Shenyang Institute of Automation,Chinese Academy of Sciences,Shenyang110016器人的自主适应能力,难以应用于需要与人体直接结合的机器人系统,如仿生假肢、外骨骼机器人及医疗康复机器人等[2].现代人机交互技术需要由机器人被动接受指令向机器人主动理解人的行为意图的方式发展,由此衍生出一类基于生物电信号的新型人机交互技术.人体生物电信号是载有人的行为信息的神经元传输到相关组织/器官时所激发的电位和,直接反应人的意图.通过解码人体生物电信号以识别人的行为,进而赋予机器人能够理解人的意图的能力,已成为人机交互研究的热点之一.目前广泛关注的生物电信号包括肌电(Electromyography, EMG)、脑电(Electroencephalography,EEG)以及眼电(Electrooculography,EOG)等[3].由于表面肌电(Surface EMG,sEMG)蕴含信息丰富,采集技术成熟,并且是无创采集,因而受到众多研究者青睐.14自动化学报42卷文献[4]简述了肌电用于机器人控制交互的优缺点,但未对意图识别技术进行深入讨论,实际上通过sEMG 实现人机交互的关键正是由sEMG 精确识别出人的运动意图[5−6],通常包括离散动作模态分类和关节连续运动量估计.前期已有学者总结了动作分类的相关研究成果,多侧重于分析sEMG 信号的处理过程及评比不同分类模型/算法的优劣[7−8];与动作分类相比,关节连续运动估计对实现机器人运动的平滑控制更有价值[9],但目前未见有文献评述这方面的研究进展;而且作为运动意图识别的延伸,基于肌电的关节刚度/阻抗估计也备受关注[10],目前也缺乏对这类研究的梳理.本文首先提炼基于sEMG 人机交互的优点,然后重点关注以下几点:1)归纳当前动作分类方法研究的特点;2)分析实现关节连续运动估计的过程,并讨论不同估计方法的应用限制;3)讨论与柔顺运动关联的关节刚度/阻抗估计方法;4)概述相关方法应用于实际系统的现状.随后,本文将总结当前研究及应用中存在的亟待突破的关键问题,并提出一些有助于实现技术革新的切入点,为后续研究提供借鉴.1基于sEMG 的人机交互的优点表面肌电是由多个活跃运动单元发放的动作电位序列沿肌纤维传播,并经由脂肪/皮肤构成的容积导体滤波后,在皮肤表面呈现的时间和空间上综合叠加的结果[11],图1展示了一组运动单元(每个运动单元包括一条运动神经以及该神经关联的肌肉纤维)[12].sEMG 是一种非平稳的微电信号,它比肢体运动一般超前30∼150ms 产生,其幅值在0.01∼10mV,主要能量集中在0∼500Hz [13].由于易受肌肉阻抗、皮肤汗液、表皮毛发及外部电磁干扰等因素影响[11,14],sEMG 的稳定采集具有一定的难度,但是随着电子技术的发展,新的检测和记录技术已比较成熟,许多表面肌电采集系统(如美国Delsys 生产的Trigno 、加拿大Thought Technology 生产的Myoscan 等)已经在医疗、科研等领域被广泛应用.图1运动单元(每条运动神经对应一个运动单元)Fig.1Motor units (One motor nerve is corresponding toone motor unit.)表面肌电电极分为多极电极和高密度电极两种.采集sEMG 前,应先选定合适的肌肉与表面电极放置点,并清洁皮肤表面(如剔除汗毛、用酒精擦拭等).表面电极捕获的sEMG 先经过放大电路放大(图2),再通过A/D 转化后输入计算机[15].对采集的sEMG 进行去除偏置/噪声预处理后,便可以作为识别运动意图的输入信号,而识别结果则用于实现人机交互控制[16].图2采集sEMG 信号Fig.2Sampling sEMG signals与传统基于固定程式控制的人机交互方式相比,基于sEMG 的人机交互有以下优点:1)可以实现机器人的自然控制(类似于人脑控制肢体运动),交互方式更容易被使用者接受;2)sEMG 依赖于驱动关节运动的肌肉,不依赖于执行运动的肢体,因此适用于肢体残疾患者;3)sEMG 超前于实际运动,可以提供运动预判;4)sEMG 蕴含肌肉力、关节力矩、关节运动量等丰富信息,可以实现多模式交互控制;5)基于sEMG 易于开发便携式或穿戴式设备.因此应用sEMG 实现人机交互,有助于利用人体行为意识发生/变化的规律,提升机器人的自主适应性,为打破人机隔阂,实现人机自然交流提供支撑;同时,该技术的推广也有利于提高助老/助残/助弱机器人的综合性能,改善社会弱势人群的生活质量.鉴于上述优点,基于sEMG 的人机交互技术已聚焦了众多研究,部分成果甚至已投入市场应用[17−18].后续将从方法研究和实际应用两个层面,分析该技术的发展概况,并剖析制约其推广应用的瓶颈.2基于sEMG 的运动意图识别方法图3展示了基于sEMG 的人机交互过程,其核心部分是通过肌电信号解码出人的运动意图[18],通常涉及到三方面问题:1)通过sEMG 识别肢体离散动作模态,例如手部的握拳、伸掌等动作[19];2)利用sEMG 估计关节连续运动量,如关节力矩、关节角度等连续量[9,16];3)而作为进一步延伸,肌肉/关节刚度/阻抗等柔顺信息估计也成为提升人机自然交互能力的关键[20].下面从这三方面探讨基于sEMG 的意图识别方法.1期丁其川等:基于表面肌电的运动意图识别方法研究及应用综述15图3基于sEMG 的人机交互过程Fig.3The process of sEMG-based HRI2.1离散动作模态分类离散动作分类是目前研究最多,方法最成熟的研究[21−22].一般流程是:1)采集肢体做不同动作时相关肌肉的sEMG;2)对sEMG 进行去偏置/噪声预处理,提取特征;3)利用sEMG 特征样本离线训练动作分类模型;4)在线利用训练的模型对新样本分类,识别动作类型;5)以识别结果作为决策输入,控制机器人执行运动(图4).sEMG 特征提取和分类模型构建是实现上述过程的最重要环节,其中sEMG 特征包括时域特征(如绝对值积分、波形长等)、频率特征(如中值频率、均值频率等)、时频域特征(如小波变换系数等)及非线性动力学特征等[23−25];而已应用的分类模型有K 近邻[24]、多层感知器[13]、高斯混合模型[26]以及支持向量机[27]等.表1总结了动作分类的部分代表性研究成果.图4基于sEMG 的离散动作分类Fig.4sEMG-based discrate-motion classification通过对表1综合分析可知,为提高动作识别效果,遴选sEMG 特征及设计sEMG 分类模型是大多数动作分类研究的主要关注点[23−28].合适的sEMG 特征组合及分类模型能有效提高动作识别效果[25],比如可以识别9种以上动作模态,识别精度最高超过95%[13].针对sEMG 特征,时域特征计算简单,但对信号的描述不充分,而频域特征一般仅用于判断肌肉疲劳度[17];因此能较全面反映信号特性的时频域特征受到更多关注,但是提取时频域特征的过程复杂、耗时多,并且构成的样本向量是高维的,故为了提高后续运算效率,常需要采用降维算法对高维样本向量降维处理[13,23].针对分类模型,线性分类器(如LDA (Latent Dirichlet allocation))简单、效率高,但对线性不可分样本无能为力[14];非线性分类器(如SVM (Support vector machine))常含有较多未知模型参数,故在训练阶段,需要较多的离线样本进行参数辨识[27];另外,硬分类器(如MLP (Multi layer perceptron))直接输出确切的类别结果,却无法在线判断分类的正确性[13];而软分类器(如Bayes 分类器、GMM (Gaussian mixture model)等)则输出样本属于某一类的概率[26],于是可以依据置信度策略在线判定分类的正确性.除筛选sEMG 特征与优化分类模型外,对sEMG 信号预处理(如去偏置/去噪、对sEMG 分解等)或对模型分类结果后处理(如多数投票[28])也受到更多的重视,这些处理方法在提升动作分类精度的同时,也有助于提升开发的肌电交互系统的鲁棒性[26,29−30].针对被识别的动作,因手/腕部动作模态组合种类繁多,故手/腕部动作识别常被用于测试算法性能;又因为利用手部残疾患者的前臂sEMG 可以复现多种手部动作[31],故研发肌电假手也受到众多研究者的青睐,而肌电假手也最有可能成为肌电交互系统推广应用的先导[13,24].另外,单一自由度动作识别已获得充分研究,多自由度同步动作或组合动作模式识别正成为新研究点,而相关成果将有助于增强肌电假肢等运动辅助设备的空间运动能力,使之具备完整复现人体自然运动的潜能[32−33].由于sEMG 具有个体特异性,且会随着人的体征(包括性别、年龄、肢体的健康/疾病/残疾等)变化而变化,因此测试者体征会直接影响动作识别结果,在开发面向特定使用者的肌电系统(如肌电假肢)时,使用者本人或相似体征测试者参与实验,获得的结果更具有参考价值[30−31,33−35];与之相应的是,为保证开发的肌电交互系统的推广应用,系统的实时性和易用性是必须关注的两个方面,实时性包括系统应用的前期训练时间短以及在线应用无操作延时[31,34](通常肌电系统的控制周期应小于300ms,使用者才不会觉察到操作延时[13,23]),易用性则是指系统具有面向不同体征使用者的开放接口[27].尽管离散动作分类研究成果层出不穷,但仍存在一些突出问题:1)动作类型是事先定义的,sEMG 受到干扰小,极少考虑人执行任务时,遇到的非理想情形,如有未知动作类型出现、传感器出现损坏等;2)对动作的描述过于简单,没有统一标准,比如伸掌动作,不同测试者可能有不同习惯,并且伸掌的力度也有区别,而这些都会对算法性能评判产生影响;3)多数结论仅通过短时实验获得,未考虑长时运动过16自动化学报42卷表1离散动作分类研究1Table1Researches on discrete-motion classification1文献sEMG特征降维/分类算法sEMG通道数动作残疾人测试?平均分类精度(%)小结[13]WPT LDA+MLP49种手/腕部动作否97.4LDA投影特征能提高动作识别精度,用于假手在线控制[23]TD,STFT,WT,WPTPCA+LDA46种上肢动作否>96WPT等时频域特征能提高动作分类精度[24]DFT幅值,ARCKNN25种手指按压动作否>93利用GA算法可自主选择与动作最相关sEMG特征[25]MAV,SSC,ARCANFIS46种手/腕部动作否92设计一种多步强化分类器,其性能优于ANN、贝叶斯分类器等[26]TD,ARC,RMSGMM46种上肢动作否>95设计并优化GMM,其分类效果优于LDA、MLP[27]RMS,ARC SVM45种手部姿势否73基于双线性变换,提出一种与个体无关的动作分类方法[28]RMS,ARC HMM46种上肢动作否94.6设计并优化HMM,其动作分类效果优于MLP[29]MAV,ZC,SSC,WLMCLPBoot67种上肢动作/姿势否92,80利用Boosting随机森林分类器降低未训练数据的干扰[30]RMS,ZC,SSC,WLLDA+ANN88种手/腕部动作是59∼92提出一种可以检测并修正动作错误分类的后处理算法[31]MAV,ZC,WL,SSCLDA1210种手/腕部动作是84.4针对单侧截肢患者,评估利用其健侧与截肢侧肌肉的sEMG进行肌电控制的效果[32]归一化sEMG值LLGMN56种手/腕部动作否82.6∼97.7利用任务上下文信息进行动作分类,完成机械臂辅助进餐实验验证[33]MAV,ZC,WL,SSC条件并联分类算法6,84∼12种手/腕单一/联合运动是93.4,89.1设计条件并联分类器,分类多自由度联合运动模态[34]RMS,log(RMS)模糊C-均值25∼9种上肢动作是79.9,92.7设计一种用户自主选择动作类的实时肌电分类方法[35]TD,ARC,RMSLDA,KNN57(高密度电极)6种手部抓取动作是>97针对颈脊髓损伤患者,由其瘫痪肢体肌肉sEMG识别出运动意图1表1中涉及的sEMG特征:时域特征(Time domain feature,TD)、短时傅里叶变换(Short-time Fourier transform,STFT)、小波变换(Wavelet transform,WT)、小波包变换(Wavelet packet transform,WPT)、离散傅里叶变换(Discrete Fourier transform,DFT)、自回归模型系数(Autoregressive model coefficients,ARC)、均方根(Root mean square,RMS)、平均绝对值(Mean absolute value,MAV)、零穿越次数(Number of zero-crossings,ZC)、波长(Wave length,WL)、斜率符号变化次数(Slope sign changes,SSC);特征投影算法:主元分析(Principal components analysis,PCA)、遗传算法(Genetic algorithm,GA);分类模型:K近邻(K-nearest neighbor,KNN)、线性判别分析(Linear discriminant analysis,LDA)、隐马尔可夫模型(Hidden Markov model,HMM)、高斯混合模型(Gaussian mixture model,GMM)、多层感知器(Multi layer perceptron,MLP)、人工神经网络(Artificial neural network,ANN)、支持向量机(Support vector machine,SVM)、对数线性高斯混合网络(Log-linearized Gaussian mixture network,LLGMN)、自适应神经模糊交互系统(Adaptive neuro-fuzzy inference system,ANFIS)、线性规划Boosting算法(Linear programming boosting algorithm,MCLPBoot).1期丁其川等:基于表面肌电的运动意图识别方法研究及应用综述17程中(比如识别手指按键动作时,连续敲键1小时),模型性能的变化.2.2关节连续运动估计动作分类只能预测少数离散肢体动作,应用预测结果控制机器人,机器人无法完成类人连续平滑运动,而保证人机运动连续匹配是实现多种服务机器人安全控制的前提,如应用于助力的外骨骼机器人[36−37]、辅助瘫痪患者康复训练的医疗康复机器人[38−40]等,因此通过sEMG估计人体关节连续运动成为肌电研究的新热点[16,41−42].利用sEMG估计关节连续运动,通常先由sEMG提取肌肉活跃度或信号包络信息(图5展示了一种求取肌肉活跃度的方法[43]),而被估运动量包括关节力矩、角速度、角度等,估计结果可以作为参考输入控制机器人.图6展示了基于sEMG的连续运动估计及机器人控制过程[44],由图6可知,精确估计人体连续运动量是发挥机器人安全辅助功能的前提.表2列出当前基于sEMG的连续运动估计的部分成果.图5一种提取肌肉活跃度u方法Fig.5A method of extracting muscle activities u通过文献检索及对表2综合分析可知,常有两类方法实现基于sEMG的关节连续运动估计.第一类方法是结合肌肉生理力学建立以sEMG为输入的关节动力学模型,进而计算关节力矩、角加速度、角速度等连续量[42−48],该方法的优点是建立的模型能够解释运动的产生过程.应用最多的肌肉力模型是Hill模型[48](图7),它是一种生理现象学模型,其中含有多个无法直接量测的生理参数,因此有效的参数辨识方法必不可少.表2关节连续运动估计研究2Table2Researches on estimation of joints continuous-movements2文献模型连续运动量sEMG通道数残疾人测试?小结[43]基于Hill模型的前向神经肌骨模型关节力矩、角速度、角度等10否建立包括肌肉活跃度、肌肉收缩、肌骨几何、关节动力/运动学等子模型的神经肌骨动力模型[45]改进的Hill肌肉力模型上肢肘/腕关节力矩28否改进Hill肌肉力模型,利用遗传算法辨识参数,构建肌电控制上肢康复系统[46]简化的Hill肌肉力模型下肢膝关节力矩6否简化Hill肌肉力模型,设计分步标定法辨识参数,构建肌电控制下肢外骨骼系统[47]神经肌骨动力学模型下肢髋/膝关节力矩16否建立“多肌肉–多肌骨”的一般化运动模型,实现多关节力矩估计[48]基于Hill模型的状态空间模型肘关节角度、角速度1否提取sEMG特征作为量测输出,建立估计关节运动的状态空间模型[49]DRNN下肢关节角度、角速度等6否设计全连接自适应DRNN网络,估计关节连续运动量[50]BPNN 下肢踝/膝/髋关节角度7是预测健康者与脊髓损伤患者的下肢关节运动,实现下肢康复设备的自主肌电控制[51]NMF,LR,ANN腕关节角度16是比较3种不同模型预测关节角度离线与在线性能[52−53]线性状态空间模型上肢关节角度及手部运动位置9否建立状态空间方程,描述肌肉活跃度与关节运动量映射关系,并引入补偿疲劳干扰的模型自适应机制[54]高阶多项式模型肘关节屈/伸角度2否利用高阶多项式插值方法建立sEMG特征与规则化肘关节角度的映射模型2表2中涉及的算法:反向传播神经网络(Back propagation neural network,BPNN)、动态递归神经网络(Dynamic recurrent neural network,DRNN)、非负矩阵分解(Non-negative matrix factorization,NMF)、线性回归(Linear regression,LR),其他同表1.18自动化学报42卷图6基于sEMG 的连续运动估计及机器人控制Fig.6sEMG-based continuous-movement estimation androbotcontrol图7Hill 肌肉模型Fig.7Hill-type muscle model第二类方法是直接建立关联sEMG 和关节连续运动量的回归模型,该方法优点是建模过程直接,对sEMG 的利用不受限.其中神经网络应用最普遍[49−51],但是神经网络的结构形式对预测结果影响很大,却没有规范方法定义合适网络结构,并且网络参数确定依赖于学习数据,当测试数据和学习数据有差异时(特别是由肌肉状态变化(如疲劳)引起的差异),易造成网络输出较大偏离真实值.与神经网络模型相比,线性或多项式模型稳定性高[52−54],但是模型对sEMG 和关节运动量的非线性关系描述不充分,其泛化能力需要进一步提高.目前还无法完整描述sEMG 与运动的内在生理–物理关系,因此不管采取何种方法,其估计的关节运动量都是近似值.而sEMG 本身具有强非线性、非平稳性、易受干扰等特点,再加上人体关节/肌肉耦合,内在生理参数难以准确量测以及人体运动的复杂多变性,都造成连续运动建模与估计比离散动作分类更困难.为了降低模型复杂度、提高模型稳定性与运动估计精度,不仅要优化肌肉选取、sEMG 信号处理过程,也要融合恰当的解耦、参数辨识及扰动补偿算法[48,52−53].通过sEMG 估计的连续运动量可以作为参考输入,进行机器人关节的同步比例控制,同时为保证人体安全及人机交互的自然协调性,采取柔顺控制策略十分必要[55].2.3刚度/阻抗估计人体肌肉/关节具有刚度/阻抗自然可调的特性,使得人体运动柔顺自如.虽然将运动估计结果用于机器人控制,可以使人机运动相匹配,但机器人还不具备柔顺性的特点.为了克服这一缺陷,研究者在运动识别的基础上,又深入探讨了与柔顺运动关联的关节刚度/阻抗等信息的估计.Tsuji 等采用平衡点扰动法估计人手阻抗,该方法繁琐,需要大量重复测试[56];Shin 等从sEMG 提取肌肉活跃度,建立映射肌肉活跃度到关节力矩的肌电运动学模型,进一步对模型微分,计算得到关节及手部刚度[57],该方法仅在肢体固定姿势条件下进行了测试验证;Kim 等构建了估计上肢多关节刚度的神经网络,网络以sEMG 与关节运动量为输入,通过简单点到点任务数据训练后,便可以估计上肢自然运动过程中多关节的时变刚度[58],该方法需要实测关节运动量,会增加应用复杂度,而且网络适用运动的范围受限于训练数据.应用估计的关节刚度实现机器人的阻抗控制,能提升机器人的类人柔顺性及人机交互的自然性.Ajoudani 等提出了一种遥阻抗控制的概念,先将肌肉活跃度空间分解成正交的力空间与刚度空间,估计出未知环境中肢体末端的三维刚度,再利用估计结果实现机器人阻抗控制.研究者将提出的方法应用于控制KuKa 机器人进行穿孔和接球实验,结果显示机器人能有效模仿人面向任务自然调节关节阻抗的特性[59];进一步Liang 等基于EMG–刚度线性映射,提出一种人操控阻抗方法.该方法利用EMG 高频段幅值估计关节刚度增量,以补偿模型非线性余差,并降低肌肉疲劳的影响.研究者利用估计的时变刚度控制Baxter 机器人进行消除外部扰动实验,验证了提出方法的有效性[60].虽然关节刚度/阻抗估计已备受关注,但当前研究还存在许多需要进一步探究的问题.刚度与关节/肌肉的生理特性相关,是肢体的一种内在属性,难以直接量测,因此刚度与sEMG 的关系模型多是在人体特定固定姿势下近似拟合的,模型的适用性受限;另外,通过sEMG 可同时估计运动量与关节刚度,而将多信息融合用于机器人控制还鲜有研究.3运动意图识别技术的应用基于sEMG 的意图识别方法多是面向实际系统提出的,由于肌电交互系统需要与人体直接接触,因1期丁其川等:基于表面肌电的运动意图识别方法研究及应用综述19此在研发系统时,除了考虑sEMG 信号处理、运动模型设计及算法实时性等因素外,还要求系统机电一体化、操作简易度、安全/稳定性等综合指标达标.3.1基于动作分类的肌电交互系统基于sEMG 动作分类技术多应用于设计肌电假手系统.西班牙CSIS 研究中心设计了一款机电一体化灵巧手MANUS-HAND (图8)[61−62],通过采集截肢者前臂残存肌肉的sEMG 识别手部6种抓取动作,依据识别结果控制假手辅助使用者完成日常任务.MANUS-HAND 的拇指、食指和中指末端各有一个力传感器用于实现类人触觉感知,此外又结合手指上的位置传感器构建了包含力和位置反馈的底层柔顺控制系统,保证操作者可以自主控制抓取模式,而无需知道物体的具体形状.图8MANUS-HAND 灵巧手Fig.8The MANUS-HAND dextrous hand德国宇航中心研发了多自由度欠驱动假肢手DRL(I,II)[63−64],DRL-II 不仅有力和位置传感器,而且在每个关节还有力矩传感器和电位计,可以实现力/位置控制及力反馈感知.研究者为DRL-II 增加了肌电控制部分,利用sEMG 控制假手抓取不同形状/重量的物体.另外,该中心和哈尔滨工业大学联合研发了具有5个手指的HIT /DRL 假肢手[65−66],哈工大研究者通过对手指动作组合编码,利用前臂3通道sEMG 识别了19种手指运动,依据识别结果实现了HIT/DRL 假手的实时控制.德国KIT 研究中心研发一款轻型仿生假手Fluidhand [67],微型液压系统驱动手指关节使其具有较大负重比.假手有两路电极,通过采集残肢sEMG 可以识别使用者的5种抓取动作,从而实现假手自然控制.Fluidhand 的食指和拇指上安装了电阻式力传感器,微处理器根据传感器信息控制一个震动马达,使用者可以根据震动强度感知抓取过程的力反馈及所触摸物体的软硬/粗糙度.与实验室应用的肌电假手相比,商业应用肌电假手功能过于简单,多数是单通道sEMG 控制的单自由度假手[68],仅能执行手的伸/握动作.英国Touch Bionics 公司研发的i-LIMB Hand 是目前世界上最先进的商业化仿生假手,能实现多自由度控制[69−70](图9).该假肢手有5个手指,每个手指由独立电机驱动.在i-LIMB Hand 的手臂筒套中安置了一对表面电极,通过采集手部缺失患者残存肌肉的sEMG,识别使用者运动意图(休息、抓握、夹、捏等),进而控制仿生手执行相应动作,并且融合了比例控制策略,sEMG 信号越强,手指运动越灵活.图9i-LIMB 仿生手Fig.9The i-LIMB bionic hand3.2基于连续运动估计的肌电交互系统动作分类会限制肌电系统运动灵活性,针对一些需要自由运动空间或自主运动模式的辅助机器人(如外骨骼机器人),则需要采用基于sEMG 的连续运动估计方法构建其人机交互系统.美国华盛顿大学研发了一款7自由度上肢外骨骼康复机器人EXO-UL3[71](图10),其自由度与人体上肢自由度相匹配,各关节由电机带动钢丝缆绳驱动.为了实现使用者对机器人的主动控制,首先,基于Hill 肌肉力模型,由上肢肌肉sEMG 计算肌肉力;然后,估计多关节力矩;再利用估计结果对外骨骼进行力矩控制.目前已应用该外骨骼机器人进行了助力/康复实验,显示出良好的辅助性能,这种基于sEMG 交互的康复策略能激发使用者在运动中自主控制患肢肌肉收缩的意识,更有利于患肢运动功能的恢复.德国柏林工业大学研发了一款下肢外骨骼助力机器人TUPLEE [44,46](图11).外骨骼包括大腿、小腿和脚部.在其大腿套筒内布置6个表面电极,采集大腿肌肉sEMG,并利用简化的Hill 肌肉力模型计算肌肉力,估计膝关节力矩后,对外骨骼进行力矩比例控制,为使用者提供辅助.同时TUPLEE 安装了测量角度和力的传感器,实时检测系统状态,防止使用者发生意外.。
林仕伟等:尖晶石型化合物的制备及光催化性能· 535 ·第38卷第3期氮掺杂二氧化钛光催化剂的研究进展胡裕龙1,2,刘宏芳1,郭兴蓬1(1. 华中科技大学化学与化工学院,武汉 430074;2. 海军工程大学理学院,武汉 430033)摘要:纯纳米二氧化钛禁带较宽,只能在紫外光下激发。
拓宽二氧化钛的光谱响应范围,实现可见光激发,是二氧化钛基光催化材料面临的主要问题。
氮掺杂二氧化钛具有良好的可见光催化活性,是具有可见光响应的二氧化钛基光催化材料的典型代表,近十年来受到了广泛关注。
本文综述氮掺杂二氧化钛可见光响应机理和提高光催化活性方面的研究进展,提出今后值得关注与研究的方向。
关键词:二氧化钛;氮掺杂;可见光;光催化活性;综合评述中图分类号:O643.1 文献标志码:A 文章编号:0454–5648(2010)03–0535–07RESEARCH PROGRESS ON NITROGEN DOPED TITANIA PHOTOCATALYSTHU Yulong1,2,LIU Hongfang1,GUO Xingpeng1(1. School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology,Wuhan 430074;2. College of Science, Naval University of Engineering, Wuhan 430033, China)Abstract: The pristine titania nanomaterial can only be excited by ultraviolet light because of its wide band-gap. Extending the opti-cal response to the visible light spectrum is one of the most important aspects to the TiO2-based photocatalyst. Nitrogen-doped titania has high visible light photocatalytic activity, which is representative of TiO2-based photocatalyst with reactivity under visible light, and has received enormous attention from scientists and engineers in the past decade. In the current review, the recent progress in research on the origins of visible light responses and the improvement of photocatalytic activity of nitrogen-doped titania are dis-cussed in detail, and urgent issues for future research and development are proposed.Key words: titania; nitrogen doping; visible light; photocatalytic activity; review纳米二氧化钛(TiO2)具有化学稳定、无毒及光催化活性好的特点,已在许多方面获得了应用。
专利名称:一种聚乙二醇固相微萃取探头及其制备方法专利类型:发明专利
发明人:帅琴,朱丹,成金华,王肖戈
申请号:CN201010268351.2
申请日:20100831
公开号:CN101936968A
公开日:
20110105
专利内容由知识产权出版社提供
摘要:本发明公开了一种聚乙二醇固相微萃取探头及其制备方法,该方法是以PEG-20M为聚合主体,按照一定比例掺杂硅氧烷类有机物制成溶胶,然后将洁净的表面具有硅羟基结构的石英纤维浸渍到该溶胶中,室温干燥,在保护气氛下老化,即得到聚乙二醇固相微萃取探头。
本发明的聚乙二醇固相微萃取探头稳定性和重现性高,吸附量大,寿命长,对极性较强的酚类化合物具有优良的萃取性能,且制备方法简单易行。
申请人:中国地质大学(武汉)
地址:430074 湖北省武汉市洪山区鲁磨路388号
国籍:CN
代理机构:武汉华旭知识产权事务所
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CHEMICAL INDUSTRY AND ENGINEERING PROGRESS 2018年第37卷第9期·3416·化 工 进展低温等离子体协同铜铈催化剂脱除甲苯甘蓉丽,罗光前,许洋,梅瑞冬,朱海露,周梦丽(华中科技大学煤燃烧国家重点实验室,湖北 武汉430074)摘要:以挥发性有机化合物(VOCs )中的代表物质甲苯作为脱除对象,采用柠檬酸水热法制得铜铈催化剂,考察了低温等离子体协同不同摩尔比铜铈催化剂脱除甲苯的性能。
研究发现铜铈复合型金属催化剂可以大幅度提升低温等离子体对甲苯的脱除效率,降低初始浓度、气体流速和升高电压可以提高甲苯脱除效率。
同时利用N 2吸附-脱附(BET )、X 射线衍射(XRD )、X 射线光电子能谱(XPS )、程序升温还原(H 2-TPR )、红外光谱(FTIR )等手段对催化剂进行表征,发现催化剂活性组分分布较均匀,铜铈复合型金属催化剂表面氧空位、吸附态氧含量高于单金属氧化物催化剂,这有利于催化剂活性氧的释放。
铜铈之间存在着协同作用,铜铈之间的氧化还原循环有利于甲苯的氧化。
关键词:甲苯;低温等离子体;铜铈催化剂;氧空位中图分类号:X511 文献标志码:A 文章编号:1000–6613(2018)09–3416–08 DOI :10.16085/j.issn.1000-6613.2017-2042Removal of toluene by non-thermal plasma coupled with Cu-Ce catalystsGAN Rongli , LUO Guangqian , XU Yang , MEI Ruidong , ZHU Hailu , ZHOU Mengli(State Key Laboratory of Coal Combustion , Huazhong University of Science and Technology, Wuhan 430074,Hubei, China )Abstract :The study investigated the removal of toluene via non-thermal plasma combined with Cu-Cecatalysts. The catalysts were prepared by the citric acid sol-gel method. Compared with the plasma-only process ,the introduction of the Cu-Ce catalysts could greatly enhance the toluene removal efficiency. The toluene removal efficiency increased with the decrease of the initial concentration or the gas flow rate and with the increase of the voltage. The catalysts were characterized by BET ,XRD ,XPS ,H 2-TPR and FTIR, respectively. The active components of the Cu-Ce catalysts distributed uniformly. The contents of oxygen vacancies and the adsorbed oxygen in the Cu-Ce catalysts were higher than those in the CuO or CeO 2 catalysts ,which is beneficial to the release of active oxygen. There was synergistic effect between Cu and Ce ,and the redox cycles between them could further promote the oxidation of toluene.Key words :toluene; non-thermal plasma; Cu-Ce catalysts; oxygen vacancy挥发性有机物(volatile organic compounds ,VOCs )在生活中广泛存在[1-2]。
CHEMICAL INDUSTRY AND ENGINEERING PROGRESS 2017年第36卷第5期·1848·化 工 进展静电自组装壳聚糖载药空心微胶囊的制备及释放性能欧敏华,张永德,罗学刚,张思月,乔丹(西南科技大学材料科学与工程学院,生物质材料教育部工程研究中心,四川 绵阳 621010)摘要:采用目前材料领域新型的自组装模板法制备了壳聚糖空心微胶囊。
首先使用分散聚合的方法合成了粒径均一的聚苯乙烯微球,粒径范围在1~2μm 。
然后用H 2SO 4将聚苯乙烯表面功能化为磺化聚苯乙烯,并以之为模板,将壳聚糖静电组装于其表面,经戊二醛交联后用四氢呋喃溶解模板,成功制备出生物相容和可降解的交联壳聚糖空心微胶囊。
研究采用凝胶渗透色谱和纳米粒度仪测试合成聚苯乙烯微球的分子量、粒径及粒度分布等性能;利用Zeta 电位仪、扫描电镜、透射电镜和热重分析仪对核-壳结构与空心微胶囊的特性进行表征。
以吡虫啉为模型药物,通过吸附与渗透的方式负载到壳聚糖交联空心微胶囊,在甲醇下进行缓释实验。
傅里叶转换红外光谱仪的表征证明氢键力在壳聚糖对吡虫啉的负载起到了重要作用。
释放实验的结果表明,壳聚糖空心微胶囊对吡虫啉的载药量达到31.78%,前期出现的释放量达56.63%,释放实验后期能保持一定的缓慢释放量,表明壳聚糖空心微胶囊的载药部位主要在其表面与内部,而进入微胶囊内部的药物则需要在交联壳聚糖降解后缓慢释出,达到所期望的缓释效果。
关键词:静电自组装;粒度分布;壳聚糖;聚电解质;微胶囊;渗透;吡虫啉中图分类号:O636.9 文献标志码:A 文章编号:1000–6613(2017)05–1848–07 DOI :10.16085/j.issn.1000-6613.2017.05.037Fabrication of electrostatic self-assembly chitosan hollow microcapsulesand study of its loading and releasing propertiesOU Minhua ,ZHANG Yongde ,LUO Xuegang ,ZHANG Siyue ,QIAO Dan(School of Materials Science and Engineering ,Research Center of Biomass Materials ,Ministry of Education ,SouthwestUniversity of Science and Technology ,Mianyang 621010,Sichuan ,China )Abstract :Chitosan hollow microcapsules ,used as pesticide-loading carrier ,were fabricated by self-assembly and sacrificial template method. Polystyrene ,as the template ,was first prepared through dispersion polymerization and sulfonated with H 2SO 4 afterward. Then the chitosan was employed to assembly onto the surface of sulfonated polystyrene electronically and cross linked it with glutaraldehyde so as to form the steady core-shell microspheres. Next ,the tetrahydrofuran was applied to the removal of template and the cross-linked chitosan hollow microcapsules were successfully fabricated. To characterize the molecular weight ,particle size and the size distribution of polystyrene microsphere ,gel permeation chromatography and nano-particle size analyzer were used. Moreover ,properties of the core-shell structure microspheres were confirmed by the zeta potentiometer ,the scanning electron microscopy ,the transmission electron microscopy ,and the thermogravimetric analyzer. The model pesticide ,imidacloprid ,was then loaded on to the chitosan hollow microcapsule by way of passive absorption and permeation ,and the release experiment was executed in methanol.大学生物质材料(教育部)工程中心平台基金项目(14tdsc01)。
大。
(2)在清洗工艺中添加壬基酚聚氧乙烯醚磷酸酯TXP、硫脲、植酸都有助于除灰率的提升。
最终确定了除油除灰二合一清洗剂的配方为:PO嵌段脂肪酸甲酯乙氧基化物FMEE6%,脂肪酸甲酯乙氧基化物磺酸盐FMES6%,伯烷基磺酸钠PAS-80 2%,乙二胺二邻苯基乙酸钠EDDHA-Na7%,乙二醇单丁醚5%,壬基酚聚氧乙烯醚磷酸酯TXP4%,硫脲3%,植酸6%,水61%。
参考文献[1]颜建辉.浅谈铝型材碱蚀工序的工艺控制[J].铝加工,2002(4):31-32.[2]何定洋,刘静安.铝板带材清洗工艺探讨[J].铝加工,2005(6):25-26.[3]唐安喜.低泡沫环氧丙烷封端FMEE的合成与性能研究[J].精细与专用化学品,2022,30(3):38-42.[4]贾路航.表面活性剂的复配及其在除油清洗中的应用[J].安徽化工,2013,39(6):37-40.[5]徐铭勋.脂肪酸甲酯乙氧基化物及其磺酸盐的生产技术与应用[J].化学工业,2012,30(7):30-32.[6]唐安喜.二元催化剂在脂肪酸甲酯乙氧基化物FMEE合成中的应用[J].中国洗涤用品工业,2022(2):34-39.[7]于兴凯,卫杰刚,左建民.乙二胺二邻苯基乙酸钠的合成以及在皂洗中的应用[J].染整技术,2012(9):35-38.[8]房秀敏.非离子表面活性剂复配与浊点的关系[J].印染助剂,1999(2):3-6.[9]张静云.壬基酚聚氧乙烯醚的生物降解行为研究[D].上海:上海交通大学,2007.[10]蒋国新,陈泽宗,姜贻成.钢铁件除蜡或除油后表面挂灰去除剂的研究[J].电镀与涂饰,2018,37(16):722-724.2023年第2期总第271期《铝加工》深加工及其他/信息报道Research and design of ash remover for aluminum alloyPan Jun(Shanghai Xihe Fine Chemical Co.,Ltd.,Shanghai201620,China)Abstract:A layer of ash will appear on the aluminum alloy under the condition of high temperature cleaning or strong alkali corro⁃sion,which is mainly composed of carbon particles and silicon particles with little diameter,no matter it is lipophilic or hydrophilic cleaning agent,it is very difficult to clean the ash thoroughly.The ash hanging on the metal surface directly affects the quality of subse⁃quent oxidation,coloring and spraying.A low temperature degreasing and ash removing cleaning agent was prepared by compounding the PO block fatty acid methyl ester ethoxylatesFMEE and FMES with the penetrating agent PAS-80,the ash removing agent ED⁃DHA-Na and the solvent2-butoxyethanol,the influence of phosphate ester,thiourea and phytic acid on the cleaning of ash was ana⁃lyzed by single factor experiment.The formula of the two-in-one cleaning agent was determined as PO block FMEE6%,FMES 6%,PAS-802%,EDDHA-Na7%,2-butoxyethanol5%,TXP4%,thiourea3%,phytic acid6%,pure water61%.Key words:blocked with PO;FMEE;FMES;degrease;ash removing中南大学一项研究获突破Al-Cu-Li合金疲劳裂纹扩展(FCP)作为疲劳损伤容限的常用性能参数之一,对影响材料的安全保证起着至关重要的作用。
doi:10.19677/j.issn.1004-7964.2023.03.003二硫化钼/石墨相氮化碳光催化降解印染废水研究卜义夫1,刘思乐1*,杜文娟2,田川1,王思祺1,万帅龙1(1.沈阳科技学院,辽宁沈阳110167;2.山东飞洋环境工程有限公司,山东济南250000)摘要:通过浸渍法和煅烧法相结合制备二硫化钼/石墨相氮化碳(MoS 2/g-C 3N 4)催化剂。
采用X 射线衍射、扫描电镜、透射电镜、紫外可见漫反射光谱、稳态荧光光谱等手段对MoS 2/g-C 3N 4催化剂的晶型、形貌、光电化学性质进行了表征,并将MoS 2/g-C 3N 4催化剂应用于印染废水的处理。
结果表明:MoS 2/g-C 3N 4催化剂呈现多孔的层状结构,对可见光有着较好的响应;在MoS 2/g-C 3N 4用量2.0g/L、pH=6、反应时间120min 的光照条件下,MoS 2/g-C 3N 4催化剂对印染废水的色度去除率和化学需氧量(COD)去除率最高,分别为89.78%和65.57%,MoS 2/g-C 3N 4催化剂循环使用5次后对印染废水的色度去除率和COD 去除率仍达到了77.28%和53.26%,具有良好的稳定性。
关键词:催化剂;光催化;印染废水;层状多孔中图分类号:TS 199文献标志码:AStudy on Photocatalytic Degradation of Printing and Dyeing Wastewater by Molybdenum Disulfide/graphite Carbon Nitride(1.Shenyang Institute of Science and Technology,Shenyang 110167,China;2.Shandong Feiyang EnvironmentalEngineering Limited Company,Jinan 250000,China)Abstract:The MoS 2/g-C 3N 4catalyst was prepared by using the impregnation and calcination methods.Its crystal form,morphology and photoelectrochemical properties were characterized by using X -ray diffraction,scanning electron microscopy,transmission electron microscopy,ultraviolet -visible diffuse reflectance spectroscopy,steady fluorescence spectrum,respectively.The MoS 2/g -C 3N 4catalyst was applied to the treatment of printing and dyeing wastewater.The results showed that the MoS 2/g-C 3N 4catalyst had a porous layered structure and good response to visible light.Under the illumination conditions with its dosage of 2.0g/L,pH=6and the reaction time of 120min,the MoS 2/g-C 3N 4catalyst had the highest chroma and chemical oxygen demand (COD)removal rates for printing and dyeing wastewater,which are 89.78%and 65.57%,respectively.After the MoS 2/g-C 3N 4catalyst was recycled for 5times,the chroma and COD removal rates of printing and dyeing wastewater still reached 77.28%and 53.26%,respectively,indicating its good stability.Key words:catalyst;photocatalysis;printing and dyeing wastewater;layered porous收稿日期:2022-09-16基金项目:国家级大学生创新创业训练计划项目(202213621001);辽宁省教育厅2022年高等学校基本科研项目面上项目(LJKM20221989);沈阳科技学院科学研究重点项目(ZD-2023-01);沈阳科技学院化学工程与工艺一流专业建设项目第一作者简介:卜义夫(2001-),男,本科生,主要从事石墨相氮化物的制备与改性工作。
CECW-EH Engineer Regulation 1110-2-1463Department of the ArmyU.S. Army Corps of EngineersWashington, DC 20314-1000ER 1110-2-146330 May 1992Engineering and DesignHYDROLOGIC ENGINEERING FORHYDROPOWERDistribution Restriction StatementApproved for public release; distribution isunlimited.DEPARTMENT OF THE ARMY ER1110-2-1463US Army Corps of EngineersCECW-EH Washington,DC20314-1000RegulationNo.1110-2-146330May1992Engineering and DesignHYDROLOGIC ENGINEERING FOR HYDROPOWER1.PurposeThis regulation defines the scope,authorities,and re-quirements for hydrologic engineering studies performed in support of hydropower studies for both conventional and pumped-storage hydroelectric projects.2.ApplicabilityThis regulation applies to all HQUSACE/OCE elements, major subordinate commands,districts,laboratories,and full operating activities having civil works engineering and design responsibilities.3.Referencesa.ER1110-2-1."Provisions for Future Hydro-power Installation at Corps of Engineers Projects."b.ER1110-2-1454."Corps Responsibilities for Non-Federal Hydroelectric Power Development Under the Federal Power Act."c.ER1110-2-1460."Hydrologic Engineering Management."d.EM1110-2-1701."Hydropower."4.Scope of Hydrologic Engineering Activities The scope of hydrologic engineering and study manage-ment is presented in Reference3c.5.Development of Hydrologic Dataa.General.Data used to support the study will be as comprehensive and as accurate as possible.b.Types of Data.The most important hydrologic data element required for a hydropower study is the long-term streamflow record that represents the flow available for power production.Other hydrologic data includes tailwater rating curves,reservoir storage-elevation-area tables,evaporation rates,flows not avail-able for power generation,streamflow routing criteria, instream flow requirements,and downstream channel constraints.The level of detail used to develop this data depends upon the stage of study in the hydropower analysis.c.Streamflow Data.(1)Length of historical period used for analysis.To accurately estimate the energy potential of a hydroelec-tric project,a streamflow record of at least20to30ye-ars should be used.If a record of this length is not available,it should be extended using one of the stan-dard techniques for extending streamflow records.The only cases where a shorter period is acceptable would be for reconnaissance level energy estimates,and even then there should be some assurance that the shorter record is representative of the long-term record.(2)Adjustment of historical records.Streamflow data may not be immediately usable for hydropower site analyses.Historical streamflow records,particularly if they span a long period of time,may have to be adjust-ed to account for diversions,reservoir regulation,and upstream land use changes.These adjustments are made so that the streamflow record is consistent throughout the period of record and so that it properly reflects conditions at some well-defined base level.6.Analysis of Project Energy Outputa.Types of analysisER1110-2-1463 30May1992(1)The three types of analyses generally used to determine the energy output of a hydroelectric project are the duration curve method,the sequential streamflow routing(SSR)method,and the hybrid method,which isa combination of the first two.(2)The duration curve method is based on a flow-duration curve and is used only for run-of-river projects where head does not vary independently of discharge.(3)The sequential streamflow routing method is based on the continuity equation and accounts for changes in streamflow due to storage regulation.This method is used for evaluating the energy output of stor-age projects or projects that are part of a system which includes one or more storage projects.(4)The hybrid method performs power computa-tions sequentially and arrays the results in duration curve format for further analysis.This method is used to examine the addition of power to projects where head varies independently of streamflow but where there is no regulation of seasonal storage for hydropower.An example would be an existing flood control reservoir or storage project where conservation storage is regulated entirely for nonpower purposes and where a substantial historical operation record is available.(5)Chapter5of Reference3d contains detailed descriptions of each of these methods,as well as addi-tional discussion on situations where each method is appropriate.b.Operating Assumptions.(1)General.When performing a duration curve analysis,specific project operating assumptions do not need to be made because the basis of the analysis is a set of historic streamflows that already reflect a specific mode of operation.However,in an SSR energy analy-sis,one of the main purposes of the analysis is to test an assumed reservoir or system operation plan.Hence, a set of operating assumptions must be defined to con-trol the operation of the reservoir.(2)Nonpower reservoir operating criteria.Most Corps of Engineers projects having a hydropower func-tion also serve other functions,such as flood control, water supply,navigation,or recreation.In modeling the operation of a given reservoir,it is necessary to specify operating criteria for each of the project functions. These would be in the form of flow objectives,reservoir elevation objectives,or a combination of the two.The reservoir will then be regulated to produce the highest possible power benefits while still meeting nonpower requirements.The nonpower operating criteria may already be well-defined,as in the case of a hydropower addition to an existing project.For new projects,both hydropower and nonpower operating criteria must be developed concurrently.(3)Power operating criteria.There are several alternative strategies that might be considered in regulat-ing the power storage at a project.Traditionally,hydro-power projects have been operated to ensure that firm energy capability will be provided in all or nearly all of the years in the period of record.It is now preferable in some power systems to operate hydroprojects to maxi-mize average annual energy or to maximize dependable capacity.A project might also be operated for variable draft for energy production(basing the draft of power storage for energy production on the market value of energy at specific times).Such an operation might be superimposed on the primary objective of maximizing firm energy output.These alternative strategies are discussed further in paragraphs5-8through5-14of Reference3d.Close coordination is required with the Federal power marketing agency1(PMA)and/or the utility system where the power is to be used to ensure that the proper reservoir operating criteria are being used.c.Study output(1)Output from a duration curve analysis.The output resulting from a duration curve analysis will include an annual generation-duration curve,an estimate of the site’s total energy potential,the average annual energy for each plant size tested,and the monthly distri-bution of generation.A generation-duration curve for the peak demand months and monthly generation-duration curves are also useful.(2)Output from a sequential streamflow routing analysis.The output resulting from a sequential streamflow routing analysis will include the plant’s average annual energy output and the month-by-month generation,discharges,and reservoir elevations for the_____________________________________________________________________________________________________ 1The Federal agency responsible for marketing the power output of the Corps project.ER1110-2-1463 30May1992period of record.For projects that are operated to maxi-mize firm energy output,the critical period must be identified and estimates developed for firm and second-ary energy production.7.Analysis of Project Dependable Capacitya.Dependable capacity.(1)Dependable capacity has traditionally been de-fined as the load-carrying ability of a powerplant under adverse load and flow conditions.This definition still applies in hydrobased power systems.However,in thermal-based power systems,other techniques may be more appropriate.Dependable capacity is used in load-resource analyses and in power sales contracts,but in the planning of hydroprojects,its major use is in esti-mating a project’s capacity benefits.(2)There are four methods for estimating hydro-plant dependable capacity:(a)the critical month method,which assesses the hydroplant’s load-carrying capability under adverse flow and load conditions; (b)the firm plant factor method,which is based upon the amount of firm energy required to make the capacity marketable;(c)the specified availability method,which is based on the amount of capacity available for a speci-fied percentage of the time,and(d)the average avail-ability method,which is based on the assumption that variation of hydroplant generating capability due to variation in streamflow and reservoir elevation is equiv-alent to variation in thermal plant availability due to outages.(3)Generally,the average availability method is to be used for hydroprojects that are operated in thermal-based power systems,while either the critical month method or the firm plant factor method is to be used for projects located in hydrobased power systems.The specified availability method is suitable only for recon-naissance level studies.The four methods are described in detail in paragraph6-7of Reference3d,along with additional discussion of the situations where each method is appropriate.b.Hydrologic Studies Required.All of the methods for computing dependable capacity require output from one of the models used for computing project energy output(paragraph6).In addition,hourly sequential streamflow routing studies may be required to test the adequacy of pondage to support the capacity and to ensure that nonpower operating constraints do not limit the usability of the capacity(paragraph8).c.Marketable capacity.As noted in para-graph7.a.(2),the average availability method is usually the preferred approach for evaluating the dependable capacity of a hydroproject operating in a thermal-based power system.The dependable capacity thus computed would be used for computing capacity benefits in an NED(National Economic Development)economic anal-ysis.However,it is also sometimes necessary to pro-vide an estimate of the project’s dependable capacity to the Federal PMA,so that they can perform the market-ability studies for the project.The PMA usually bases its analyses on the capacity that can be supported under adverse water conditions.This is appropriate,because in most cases the PMA has only hydropower to market, so they are interested in the contribution the hydro-project makes to its own(all-hydro)load-carrying capability rather than its contribution to the entire regional power system,as would be the case in an NED economic analysis.To avoid confusion with the NED dependable capacity,the value provided to the PMA should be identified as the marketable capacity.The marketable capacity would be computed using either the critical month or firm plant factor method,depending on the practices of the specific PMA.8.Water Surface Fluctuation Studiesa.Because of their ability to come on line quickly and to respond quickly to changes in load,hydroprojects are highly valuable to power systems when operated as peaking projects.However,peaking operation often results in rapid fluctuations in discharge and in water surface elevations both upstream and downstream from the powerplant.If a hydroproject is being considered for peaking operation,it is necessary to evaluate the effect of the power operations on the shoreline of the reservoir and on riparian land downstream from the project site.Studies of this type are particularly impor-tant at the advanced feasibility and General Design Memoranda stages and are required for both conven-tional and pumped-storage hydroprojects.b.Areas of concern may include safety of and access to shoreline areas for commercial and recreational activities;maintenance of safe depths and velocities for navigation;adequate depth for operation of water supply and irrigation pumping facilities and sew-age treatment plant outfalls;and damage to waterfowlER1110-2-1463 30May1992nesting areas,fish migration channels and spawning areas,and habitat areas of rare or endangered species.c.Water surface fluctuation studies will usually require hydraulic modeling techniques based on un-steady flow theory when there are rapid fluctuations in discharge.9.Pumped-Storage Hydropower Projectsa.Average annual energy output and dependable capacity are computed differently for pumped-storage projects than for conventional hydropower projects.In addition,the average annual pumping energy required to support the pumped-storage operation must be comput-ed.The details of such analyses are described in Chap-ter7of Reference3d;however,several key points should be noted.b.Close coordination must be maintained with the Federal PMA and/or the utility that will be using the output of the project at all stages of the study to ensure that the project output will be usable in the system load, that sufficient low-cost pumping energy will be avail-able to support the project,and that sufficient storage will be available in both the upper and lower reservoirs to support the power operation and to meet other project purposes.c.Average annual generation and pumping energy requirements should in most cases be estimated by simulating the operation of the project in an hourly production cost model of the power system in which the project would be operating.This is the preferred method of analysis,because it simulates the operation of the project under a range of conditions similar to those in which the project would be expected to operate.An alternative method is based on an assumed operating cycle.This method involves more guesswork,and experience has proven that it often overestimates the amount of generation a project would produce.It should be used only where the project would operate according to a fixed dispatch schedule instead of the economic dispatch mode.In such cases some assurance should be received from the PMA or the utility customer that the proposed operating schedule can be supported with economical pumping energy.Even when this method is used,the proposed operation should also be tested in a system production cost model to verify that such an operation is possible within the system load shape.10.Documentation and ReportingHydrologic studies for hydropower are documented in technical reports or in technical appendices to project reports.The report or appendix presents a description of the data used,methods employed,assumptions made, and results obtained.A complete and well written report is required and must be of sufficient detail to allow an independent reviewer to follow the described analyses and support the study findings.Appendix A of Reference3d lists the type of information that should be included in a feasibility report.FOR THE COMMANDER:Colonel,Corps of EngineersChief of Staff。