紫外分光光度计测量甲基硫菌灵和多菌灵的含量

紫外分光光度计测量甲基硫菌灵和多菌灵的含量 施张胜 12011001399 摘要:本文首先对紫外分光光度计工作原理、分类、结构、优点等作了一些基本的介绍。然后再通过紫外分光光度计测量甲基硫菌灵和多菌灵的含量，进而让大家对紫外分光光度计有更加全面的了解。 关键词:甲基硫菌灵;多菌灵;紫外分光光度计 一 对紫外分光光度计的介绍 紫外-可见分光光度法的特点 与其它光谱方法相比，其仪器设备和操作都比较简单、费用少、分析速度快、灵敏度高 、选择性好精密度和准确度较高、 用途广泛。 紫外分光光度计的原理 它是利用物质的分子或离子对某一波长范围的光的吸收作用，对物质进行 rAt present, we have formed a "three-three" Park. …… Industrial Park, according to ... ... The instructions of comrade, focus on development needs in the next decade, based on the original, and then extended the 6 square kilometers. Of the Park, to further improve the roads, power supply, communications, water supply and drainage and sewage pipe network and other infrastructure, to achieve full coverage of infrastructure and interconnection with the facilities and raise capacity. Each park to determine 1 leading industries, in particular stone Materials, cans, gloves, through guided, force and other measures to promote the "road company" Park, industrial agglomeration. Currently, to focus on building better ... ... Industrial Park, ... ... Wood Park as the starting area of the industrial park, planners need to take out plan, start construction as soon as possible, undertake in a timely manner ... ... Transfer of the wood industry. This opportunity slip by, so the timing must be tight. Second is to optimize government service. Low efficiency of government services, departments do not coordinate the views of businesses large, poor business environment, it is ... ... Short Board, decide to change. We will continue to deepen reform of the administrative examination and approval system, good digestion, implement the Government canceled, adjustment and devolution of administrative examination and approval matters, strengthen the existing supervision in matters of administrative power, has made it clear to cancel, are not allowed to keep or disguised approval. To do list list of administrative powers and responsibilities 定性分析、定量分析及结构分析, 所依据的光谱是分子或离子吸收入射光中特定波长的光而产生的吸收光谱。按所吸收光的波长区域不同，分为紫外分光光度法和可见分光光度法，合称为紫外-可见分光光度法。 物质对光的吸收是选择性的，利用被测物质对某波长的光的吸收来了解物质的特性，这就是光谱法的基础。通过测定被测物质对不同波长的光的吸收强度(吸光度)，以波长为横坐标，吸光度为纵坐标作图，得出该物质在测定波长范围的吸收曲线。在吸收曲线中，通常选用最大吸收波长λmax进行物质含量的测定。 朗伯-比尔定律是紫外-可见分光光度法的理论基础。朗伯-比尔定律:当一束平行单色光通过含有吸光物质的稀溶液时，溶液的吸光度与吸光物质浓度、液层厚度乘积成正比，即A= κ cl 式中比例常数κ与吸光物质的本性，入射光波长及温度等因素有关。c为吸光物质浓度，l为透光液层厚度。设入射光强度 ，反射光强度为Ir，则I0= Ia+ It+ 为I0，吸收光强度为Ia,透射光强度为 It Ir 由于反射光强度基本相同，其影响可相互抵消，上式可简化为:I0= Ia+ It 透光度:透光度为透过光的强度It与入射光强度I0之比，用T示:即 T= rAt present, we have formed a "three-three" Park. …… Industrial Park, according to ... ... The instructions of comrade, focus on development needs in the next decade, based on the original, and then extended the 6 square kilometers. Of the Park, to further improve the roads, power supply, communications, water supply and drainage and sewage pipe network and other infrastructure, to achieve full coverage of infrastructure and interconnection with the facilities and raise capacity. Each park to determine 1 leading industries, in particular stone Materials, cans, gloves, through guided, force and other measures to promote the "road company" Park, industrial agglomeration. Currently, to focus on building better ... ... Industrial Park, ... ... Wood Park as the starting area of the industrial park, planners need to take out plan, start construction as soon as possible, undertake in a timely manner ... ... Transfer of the wood industry. This opportunity slip by, so the timing must be tight. Second is to optimize government service. Low efficiency of government services, departments do not coordinate the views of businesses large, poor business environment, it is ... ... Short Board, decide to change. We will continue to deepen reform of the administrative examination and approval system, good digestion, implement the Government canceled, adjustment and devolution of administrative examination and approval matters, strengthen the existing supervision in matters of administrative power, has made it clear to cancel, are not allowed to keep or disguised approval. To do list list of administrative powers and responsibilities It/I0吸光度: 为透光度倒数的对数，用A表示即A=lg1/T=lgI0/It。 偏离朗伯-比耳定律的因素(1)入射光为非单色光(2)溶液的不均性。 实际样品的混浊，加入的保护胶体，蒸馏水中的微生物，存在散射以及共振发射等，均可吸光质点的吸光特性变化大。(3)光程的不一致性。光源不是点光源，比色皿光径长度不一致，光学元件的缺陷引起的多次反射等，均造成光径不一致，从而与定律偏离。 紫外-可见分光光度计主要部件的性能与作用 基本结构:光源?单色器?吸收池?检测器?信号显示系统 光源:在紫外可见分光光度计中，常用的光源有两类:热辐射光源和气体放电光源 。单色器:单色器的主要组成:入射狭缝、出射狭缝、色散元件和准直镜等部分。单色器质量的优劣，主要决定于色散元件的质量。色散元件常用棱镜和光栅。吸收池:吸收池又称比色皿或比色杯，按材料可分为玻璃吸收池和石英吸收池，前者不能用于紫外区。吸收池的种类很多，其光径可在0.1~10cm之间，其中以1cm光径吸收池最为常用。检测器:检测器的作用是检测光信号，并将光信号转变为电信号。现今使用的分光光度计大多采用光电管或光电倍增 rAt present, we have formed a "three-three" Park. …… Industrial Park, according to ... ... The instructions of comrade, focus on development needs in the next decade, based on the original, and then extended the 6 square kilometers. Of the Park, to further improve the roads, power supply, communications, water supply and drainage and sewage pipe network and other infrastructure, to achieve full coverage of infrastructure and interconnection with the facilities and raise capacity. Each park to determine 1 leading industries, in particular stone Materials, cans, gloves, through guided, force and other measures to promote the "road company" Park, industrial agglomeration. Currently, to focus on building better ... ... Industrial Park, ... ... Wood Park as the starting area of the industrial park, planners need to take out plan, start construction as soon as possible, undertake in a timely manner ... ... Transfer of the wood industry. This opportunity slip by, so the timing must be tight. Second is to optimize government service. Low efficiency of government services, departments do not coordinate the views of businesses large, poor business environment, it is ... ... Short Board, decide to change. We will continue to deepen reform of the administrative examination and approval system, good digestion, implement the Government canceled, adjustment and devolution of administrative examination and approval matters, strengthen the existing supervision in matters of administrative power, has made it clear to cancel, are not allowed to keep or disguised approval. To do list list of administrative powers and responsibilities 管作为检测器。信号显示系统:常用的信号显示装置有直读检流计，电位调节指零装置，以及自动记录和数字显示装置等。 紫外-可见分光光度计的类型 按其光学系统可分为单波长分光光度计和双波长分光光度计1.单波长单光束分光光度计目前国内广泛采用721型分光光度计。具有结构简单、价格低廉、操作方便、维修也比较容易，适用于常规分析。单波长单光束分光光度计还有国产751型、XG-125型、英国SP500型和伯克曼DU-8型等。2.单波长双光束分光光度计。单波长双光束分光光度计有国产710型、730型、740型、日立UV-340型等就属于这种类型。3.双波长分光光度计。 rAt present, we have formed a "three-three" Park. …… Industrial Park, according to ... ... The instructions of comrade, focus on development needs in the next decade, based on the original, and then extended the 6 square kilometers. Of the Park, to further improve the roads, power supply, communications, water supply and drainage and sewage pipe network and other infrastructure, to achieve full coverage of infrastructure and interconnection with the facilities and raise capacity. Each park to determine 1 leading industries, in particular stone Materials, cans, gloves, through guided, force and other measures to promote the "road company" Park, industrial agglomeration. Currently, to focus on building better ... ... Industrial Park, ... ... Wood Park as the starting area of the industrial park, planners need to take out plan, start construction as soon as possible, undertake in a timely manner ... ... Transfer of the wood industry. This opportunity slip by, so the timing must be tight. Second is to optimize government service. Low efficiency of government services, departments do not coordinate the views of businesses large, poor business environment, it is ... ... Short Board, decide to change. We will continue to deepen reform of the administrative examination and approval system, good digestion, implement the Government canceled, adjustment and devolution of administrative examination and approval matters, strengthen the existing supervision in matters of administrative power, has made it clear to cancel, are not allowed to keep or disguised approval. To do list list of administrative powers and responsibilities 二 对甲基硫菌灵和多菌灵含量的测量 对甲基硫菌灵的介绍 甲基硫菌灵(又名甲基托布津)是一种广范谱内吸型杀菌剂,被广泛用于防治果品的轮纹病和黑腐病及贮藏期的青霉病和绿霉病等。但因生产商和销售环节的违规操作,使果品中甲基硫菌灵的含量超过国家(GB14870-94)规定,最高留限量每千克不超过0?5mg。为防止高残留农药的果品及加工品上市,国家要求销售前按国标SN0162-92用气相色谱—质谱仪法,测定甲基硫菌灵的含量。但仪器昂贵,操作技术复杂。为此介绍一种简便易行、准确可靠、一般实验室即可测试的紫外分光光度计测定法。 对甲基硫菌灵和多菌灵含量的测量 a. 标准储备液和使用液的配制 精确称取50mg甲基硫菌灵可湿性粉剂,放入烧杯中,用三氯甲烷溶解,定容至50ml。从中准确吸取10?00ml甲基硫菌灵的标准液,移入100ml容量瓶中,用三氯甲烷稀释至刻度,制成甲基硫菌灵标准使用液。同样精确称取50mg多菌灵放入 rAt present, we have formed a "three-three" Park. …… Industrial Park, according to ... ... The instructions of comrade, focus on development needs in the next decade, based on the original, and then extended the 6 square kilometers. Of the Park, to further improve the roads, power supply, communications, water supply and drainage and sewage pipe network and other infrastructure, to achieve full coverage of infrastructure and interconnection with the facilities and raise capacity. Each park to determine 1 leading industries, in particular stone Materials, cans, gloves, through guided, force and other measures to promote the "road company" Park, industrial agglomeration. Currently, to focus on building better ... ... Industrial Park, ... ... Wood Park as the starting area of the industrial park, planners need to take out plan, start construction as soon as possible, undertake in a timely manner ... ... Transfer of the wood industry. This opportunity slip by, so the timing must be tight. Second is to optimize government service. Low efficiency of government services, departments do not coordinate the views of businesses large, poor business environment, it is ... ... Short Board, decide to change. We will continue to deepen reform of the administrative examination and approval system, good digestion, implement the Government canceled, adjustment and devolution of administrative examination and approval matters, strengthen the existing supervision in matters of administrative power, has made it clear to cancel, are not allowed to keep or disguised approval. To do list list of administrative powers and responsibilities 50ml容量瓶中,用1mol/L盐酸溶液溶解并定容至刻度。再准确吸取10?00ml多菌灵标准储备液,移入100ml容器瓶中,用1mol/L盐酸溶液定容至刻度,制成多菌灵标准使用液。 b. 待测样品的提取和分离 随机抽取果实样品,用清水洗去泥沙,晾干或用吸水纸吸干果实表面的水。将果实纵切分成两等份,取果肉部分,置于干燥的组织捣碎机或研钵内破碎磨细。称取50g果泥样品,加50ml甲醇,用高速离心机(每分钟6000转)离心分离10分钟,移上清液于烧杯中。沉淀物用20ml甲醇搅匀后,加水10m,l作用10分钟,再 次高速离心10分钟。上清液并入盛滤液的烧杯中,在80?水浴上用热空气流吹去部分甲醇,倒入分液漏斗中,加10%的氯化钠溶液30ml和25ml石油醚,混合摇动2分钟后,再加25ml石油醚振摇2分钟以充分提取待测物药液。除去石油醚,加盐酸提高酸度至pH值1~2,用二氯甲烷提取两次(每次加25m,l作用2分钟)。合并两次的提取液,用25ml蒸馏水洗涤1次,用尖嘴吸管吸出二氯甲烷层,移入干燥的分液漏斗中,供甲基硫菌灵含量测定之用。水洗液合并入水层,留作多菌灵测定用。 rAt present, we have formed a "three-three" Park. …… Industrial Park, according to ... ... The instructions of comrade, focus on development needs in the next decade, based on the original, and then extended the 6 square kilometers. Of the Park, to further improve the roads, power supply, communications, water supply and drainage and sewage pipe network and other infrastructure, to achieve full coverage of infrastructure and interconnection with the facilities and raise capacity. Each park to determine 1 leading industries, in particular stone Materials, cans, gloves, through guided, force and other measures to promote the "road company" Park, industrial agglomeration. Currently, to focus on building better ... ... Industrial Park, ... ... Wood Park as the starting area of the industrial park, planners need to take out plan, start construction as soon as possible, undertake in a timely manner ... ... Transfer of the wood industry. This opportunity slip by, so the timing must be tight. Second is to optimize government service. Low efficiency of government services, departments do not coordinate the views of businesses large, poor business environment, it is ... ... Short Board, decide to change. We will continue to deepen reform of the administrative examination and approval system, good digestion, implement the Government canceled, adjustment and devolution of administrative examination and approval matters, strengthen the existing supervision in matters of administrative power, has made it clear to cancel, are not allowed to keep or disguised approval. To do list list of administrative powers and responsibilities c. 测定残毒 1 绘制标准曲线 准确吸取0?0、0?1、0?3、0?5ml甲基硫菌灵标准使用液(相当于0、10、30、50μg甲基硫菌灵),分别置于30ml圆底离心器中,离心挥干溶剂后,各加入10ml乙酸-乙酸铜溶液及2~5粒玻璃珠,接上空气冷凝器,于酒精灯或微型电炉上缓缓加热煮沸30分钟取下,用20ml浓度为1mol/L的盐酸洗涤冷凝管和圆底离心管,作用2分钟。将液体移入125ml分液漏斗中。用二氯甲烷提取2次,每次用量10ml。用尖嘴吸管吸出二氯甲烷层移入备用的干燥分液漏斗中。上述酸溶液用2mol/L的氢氧化钠中和,调整pH值至6?0~6?5(碱液用量为25ml),中和液用二氯甲烷提取2次,每次20m,l把两次的提取液合并在一起,再用10ml蒸馏水洗涤分液漏斗,静置分层后,将二氯甲烷层并入另一存有二氯甲烷层的分液漏斗中。准确加入10ml浓度为1mol/L盐酸,再次提取5分钟,静置10分钟左右。待分层后,将酸提取液倒入1cm石英双色杯中,用1mol/L的盐酸调节分光光度计的零点,在波长282nm处分别测0~50μg甲基硫菌灵标准液的吸光度(A282)。以A282值为纵坐标,甲基硫菌灵的含量为横坐标,绘制甲基硫菌灵的标准曲线。准确吸取0?0、0?1、 rAt present, we have formed a "three-three" Park. …… Industrial Park, according to ... ... The instructions of comrade, focus on development needs in the next decade, based on the original, and then extended the 6 square kilometers. Of the Park, to further improve the roads, power supply, communications, water supply and drainage and sewage pipe network and other infrastructure, to achieve full coverage of infrastructure and interconnection with the facilities and raise capacity. Each park to determine 1 leading industries, in particular stone Materials, cans, gloves, through guided, force and other measures to promote the "road company" Park, industrial agglomeration. Currently, to focus on building better ... ... Industrial Park, ... ... Wood Park as the starting area of the industrial park, planners need to take out plan, start construction as soon as possible, undertake in a timely manner ... ... Transfer of the wood industry. This opportunity slip by, so the timing must be tight. Second is to optimize government service. Low efficiency of government services, departments do not coordinate the views of businesses large, poor business environment, it is ... ... Short Board, decide to change. We will continue to deepen reform of the administrative examination and approval system, good digestion, implement the Government canceled, adjustment and devolution of administrative examination and approval matters, strengthen the existing supervision in matters of administrative power, has made it clear to cancel, are not allowed to keep or disguised approval. To do list list of administrative powers and responsibilities 0?3、0?5ml多菌灵标准使用液(相当于0、10、30、50μg多菌灵),放入分液漏斗各加入20ml浓度为1mol/L的盐酸,用二氯甲烷提取2次,每次用10ml。用尖嘴吸管吸出二氯甲烷层,移入干燥的分液漏斗中。酸液用2mol/L的氢氧化钠溶液中和至pH值6?0~6?5,用二氯甲烷提取2次,每次20m,l提取液用10ml蒸馏水洗涤1次。静置分层后,将两次的二氯甲烷层合并,准确加入10ml浓度为1mol/L的盐酸,再次酸提5分钟。静置10分钟。待分层后,将酸提液倒入1cm石英双色杯中,用1mol/L的盐酸调节分光光度计的零点。在波长282nm处分别测0~50μg多菌灵标准液的吸光度值(A282)。以A282值为纵坐标,多菌灵的含量为横坐标,绘制多菌灵的标准曲线。 2 测定果品中的甲基硫菌灵和多菌灵含量 取果肉的二氯甲烷提取液,自然挥干或加热挥干后,用10ml乙酸-乙酸铜溶液分次溶解残渣,并移入30ml圆底离心器中,加2~5粒玻璃珠,接上空气冷凝管, 浓度为1mol/L的盐酸从冷凝用酒精灯或微型电炉缓缓煮沸30分钟取下,用20ml 管顶端洗涤冷凝管和圆底离心管,作用2分钟。将液体移入125ml分液漏斗中,用二氯甲烷提取2次,每次用量10ml。用尖嘴吸管吸出二氯甲烷层移入备用的干燥 rAt present, we have formed a "three-three" Park. …… Industrial Park, according to ... ... The instructions of comrade, focus on development needs in the next decade, based on the original, and then extended the 6 square kilometers. Of the Park, to further improve the roads, power supply, communications, water supply and drainage and sewage pipe network and other infrastructure, to achieve full coverage of infrastructure and interconnection with the facilities and raise capacity. Each park to determine 1 leading industries, in particular stone Materials, cans, gloves, through guided, force and other measures to promote the "road company" Park, industrial agglomeration. Currently, to focus on building better ... ... Industrial Park, ... ... Wood Park as the starting area of the industrial park, planners need to take out plan, start construction as soon as possible, undertake in a timely manner ... ... Transfer of the wood industry. This opportunity slip by, so the timing must be tight. Second is to optimize government service. Low efficiency of government services, departments do not coordinate the views of businesses large, poor business environment, it is ... ... Short Board, decide to change. We will continue to deepen reform of the administrative examination and approval system, good digestion, implement the Government canceled, adjustment and devolution of administrative examination and approval matters, strengthen the existing supervision in matters of administrative power, has made it clear to cancel, are not allowed to keep or disguised approval. To do list list of administrative powers and responsibilities 分液漏斗中。上述酸溶液用2mol/L的氢氧化钠中和,调整pH值6?0~6?5(碱液用量为25ml)。中和液用二氯甲烷提取2次,每次20m,l把两次的提取液合并在一起,再用10ml蒸馏水洗涤分液漏斗,静置分层后,将二氯甲烷层并入另一种存有二氯甲烷层的分液漏斗中,准确加入10ml浓度为1mol/L的盐酸,再次提取5分钟,静置10分钟左右。待分层后,将酸提取液倒入1cm石英双色杯中,用1mol/L的盐酸调节分光光度计零点。在波长282nm处测样品的吸光度。与甲基硫菌灵的标准曲线比较,计算样品中甲基硫菌灵的含量。取“待测样品的提取和分离”中的多菌灵测定液,用2mol/L氢氧化铵溶液中和至pH值6?0~6?5,用二氯甲烷提取2次,每次20m,l提取液用10ml蒸馏水洗涤1次,静置分层后,将两次的二氯甲烷层合并,准确加入10ml浓度为1mol/L盐酸,再次酸提5分钟。静置10分钟,待分层后,将酸提液倒入1cm石英双色杯中,用1mol/L的盐酸调节分光光度计零点。在波长282nm处测定样品的吸光度。与多菌灵的标准曲线比较,计算样品中多菌灵的含量。 测定结果按下式计算: X=V1×Cm×V2×100 式中V1为加入提取溶剂的总毫升数;m为样品重量(g);V2为测定时使用提取溶剂 rAt present, we have formed a "three-three" Park. …… Industrial Park, according to ... ... The instructions of comrade, focus on development needs in the next decade, based on the original, and then extended the 6 square kilometers. Of the Park, to further improve the roads, power supply, communications, water supply and drainage and sewage pipe network and other infrastructure, to achieve full coverage of infrastructure and interconnection with the facilities and raise capacity. Each park to determine 1 leading industries, in particular stone Materials, cans, gloves, through guided, force and other measures to promote the "road company" Park, industrial agglomeration. Currently, to focus on building better ... ... Industrial Park, ... ... Wood Park as the starting area of the industrial park, planners need to take out plan, start construction as soon as possible, undertake in a timely manner ... ... Transfer of the wood industry. This opportunity slip by, so the timing must be tight. Second is to optimize government service. Low efficiency of government services, departments do not coordinate the views of businesses large, poor business environment, it is ... ... Short Board, decide to change. We will continue to deepen reform of the administrative examination and approval system, good digestion, implement the Government canceled, adjustment and devolution of administrative examination and approval matters, strengthen the existing supervision in matters of administrative power, has made it clear to cancel, are not allowed to keep or disguised approval. To do list list of administrative powers and responsibilities 的毫升数;C为相当于标准浓度(mg);X为样品中甲基硫菌灵的含量(mg/kg)。 (注意:用石油醚和二氯甲烷萃取的整个过程,不论加入量还是取出量,必须准 确、快速。当甲基硫菌灵残留量过高时,可减少样品的用量或增加稀释倍数。) rAt present, we have formed a "three-three" Park. …… Industrial Park, according to ... ... The instructions of comrade, focus on development needs in the next decade, based on the original, and then extended the 6 square kilometers. Of the Park, to further improve the roads, power supply, communications, water supply and drainage and sewage pipe network and other infrastructure, to achieve full coverage of infrastructure and interconnection with the facilities and raise capacity. Each park to determine 1 leading industries, in particular stone Materials, cans, gloves, through guided, force and other measures to promote the "road company" Park, industrial agglomeration. Currently, to focus on building better ... ... Industrial Park, ... ... Wood Park as the starting area of the industrial park, planners need to take out plan, start construction as soon as possible, undertake in a timely manner ... ... Transfer of the wood industry. This opportunity slip by, so the timing must be tight. Second is to optimize government service. Low efficiency of government services, departments do not coordinate the views of businesses large, poor business environment, it is ... ... Short Board, decide to change. We will continue to deepen reform of the administrative examination and approval system, good digestion, implement the Government canceled, adjustment and devolution of administrative examination and approval matters, strengthen the existing supervision in matters of administrative power, has made it clear to cancel, are not allowed to keep or disguised approval. To do list list of administrative powers and responsibilities 三 参考文献 [1]徐林华，李相银.非晶态Zno结构及光学性质[J].2008,6 [2]陈长乐(固体物理学[M](北京:科学出版社，2007( [3]赵文宽.仪器分析 [M].北京:高等教育出版社，2001 [4]李庆，李文新(紫外分光光度计测量甲基硫菌灵和多菌灵的含量[J](DECIDUOUS FRUITS 2007(3) rAt present, we have formed a "three-three" Park. …… Industrial Park, according to ... ... The instructions of comrade, focus on development needs in the next decade, based on the original, and then extended the 6 square kilometers. Of the Park, to further improve the roads, power supply, communications, water supply and drainage and sewage pipe network and other infrastructure, to achieve full coverage of infrastructure and interconnection with the facilities and raise capacity. Each park to determine 1 leading industries, in particular stone Materials, cans, gloves, through guided, force and other measures to promote the "road company" Park, industrial agglomeration. Currently, to focus on building better ... ... Industrial Park, ... ... Wood Park as the starting area of the industrial park, planners need to take out plan, start construction as soon as possible, undertake in a timely manner ... ... Transfer of the wood industry. This opportunity slip by, so the timing must be tight. Second is to optimize government service. Low efficiency of government services, departments do not coordinate the views of businesses large, poor business environment, it is ... ... Short Board, decide to change. We will continue to deepen reform of the administrative examination and approval system, good digestion, implement the Government canceled, adjustment and devolution of administrative examination and approval matters, strengthen the existing supervision in matters of administrative power, has made it clear to cancel, are not allowed to keep or disguised approval. To do list list of administrative powers and responsibilities