Spectral Modeling Synthesis Past and Present

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电化学原位紫外可见反射谱用于表面等离激元效应的表征

第３８卷，第１０期光谱学与光谱分析Ｖｏｌ．３８，Ｎｏ．１０，ｐｐ３７３－３７４２　０　１　８年１　０月Ｓｐｅｃｔｒｏｓｃｏｐｙ　ａｎｄ　Ｓｐｅｃｔｒａｌ　Ａｎａｌｙｓｉｓ　Ｏｃｔｏｂｅｒ，２０１８　电化学原位紫外可见反射谱用于表面等离激元效应的表征王家正，刘　佳，周剑章＊，吴德印＊，田中群福建省厦门市厦门大学化学化工学院，福建厦门　３６１００５摘　要　在锁相放大技术的基础上，搭建了光检测系统与恒电位系统联用的电化学原位紫外－可见电反射光谱测量系统，并将其应用于表面等离激元体系的反射率表征。

对光滑银电极和银纳米粒子修饰电极进行了电化学原位反射光谱测量，得到在不同电位下的反射光谱变化，发现在纳米粒子修饰电极上，产生强的反射谱峰。

推测这种谱峰来自于纳米间隙结构造成的热点效应，电位可显著地调控纳米间隙结构的光散射效应。

关键词　紫外－可见光谱；表面等离激元共振；电化学原位光谱；纳米间隙文献标识码：Ａ文章编号：１０００－０５９３（２０１８）１０－０３７３－０２　收稿日期：２０１８－０４－３０，修订日期：２０１８－０７－０１　基金项目：国家自然科学基金项目（２１５３３００６，２１６２１０９１，２１２７３１８２）资助　作者简介：王家正，１９９５年生，厦门大学固体表面物理化学国家重点实验室博士研究生＊通讯联系人ｅ－ｍａｉｌ：ｊｚｚｈｏｕ＠ｘｍｕ．ｅｄｕ．ｃｎ；ｄｙｗｕ＠ｘｍｕ．ｅｄｕ．ｃｎ在外来电磁波的激发下，金属纳米粒子内部的自由电子发生集体振荡，形成局域表面等离激元。

当外来电磁波的频率与自由电子的振荡频率一致时，电磁波与自由电子运动发生最大限度耦合，这种现象叫局域表面等离激元共振（ＬＳＰＲ）［１］。

ＬＳＰＲ现象在光谱上表现为消光峰，而对于贵金属如金、银的纳米粒子，其ＬＳＰＲ峰一般位于可见光区域，因此利用电化学原位紫外－可见光谱，可对电化学条件下金属纳米粒子的ＬＳＰＲ性质进行研究。

Ｆｉｇ．１　Ｉｎ－ｓｉｔｕ　ＵＶ－Ｖｉｓ　ｅｌｅｃｔｒｏｒｅｆｌｅｃｔａｎｃｅ　ｓｐｅｃｔｒａ　ｏｆ　ｓｍｏｏｔｈ　ｓｉｌ－ｖｅｒ　ｅｌｅｃｔｒｏｄｅ　ｕｎｄｅｒ　ｄｉｆｆｅｒｅｎｔ　ｐｏｔｅｎｔｉａｌｓ（ｖｓ．Ａｇ／ＡｇＣｌ）对光滑银电极和银纳米粒子修饰的银电极进行了电化学原位反射光谱的表征，主要考察这两种电极在不同电位下对垂直入射光的反射率变化。

MATLAB在电机教学中的应用_赵静

福建电脑2012年第1期(下转第63页)MATLAB 在电机教学中的应用赵静（中州大学工程技术学院河南郑州450044）【摘要】：为提高教学质量，将MATLAB 软件应用于电机教学中。

建立了直流电动机的数学模型，对直流电动机的启动过程进行了仿真研究。

仿真结果表明MATLAB 是电机教学的重要工具。

【关键词】：软件;电机;仿真1、引言电机是一门理论性很强的专业基础课，同时又具有专业课的性质[1]，在整个课程体系中起着承上启下的作用。

课程中电机的结构、时空图和电磁关系等内容，都与三维空间有关，仅借助板书和老师的讲解很难表达透彻，学生理解较困难[2]。

MATLAB 是美国MathWorks 公司开发的一种软件库，具有强大的运算处理能力和方便实用的绘图功能，尤其是其中的Simulink 图形界面环境，使各种工程问题的求解和仿真更具有简洁性和直观性。

将MATLAB 应用于电机教学中，利用其电力系统仿真工具箱提供的丰富的算法程序可完成电机系统的建模、分析和设计，用一系列直观、准确、运动的图像展示抽象概念的含义，使学生较快地掌握该课程的精神实质，提高教学效果。

2、应用实例电动机的启动是最重要的一部分，由于直流电动机的电枢绕组电阻很小，因此不能直接启动，否则会产生很大的启动电流。

为限制该电流，可采取降低电源电压的方法。

单纯的理论讲解不能使学生对启动过程产生直观认识，利用MATLAB 软件对该过程仿真，则会极大提高教学效果。

2.1直流电动机数学模型的建立MATLAB 的Power System Block 中已经提供了各种各样的电机模型，但也可以根据不同的数学模型搭建自己所需要的电机。

以他励直流电动机为例来说明。

他励直流电动机有两个独立的电路：电枢回路和励磁回路，如图1所示。

为直观起见，电枢电阻R a 和漏磁电感L a 单独画出[3]。

额定励磁下电枢回路的电压方程为：（1）其中，e=Kn 为反电动势。

若忽略空载转矩，电动机的运动方程为：（2）式中，转动惯量J=GD 24g ；角速度ω=2πn60；T e =Ci a 为额定励磁下的电磁转矩，T L 为负载转矩，GD 2为电力拖动系统部分折算到电动机轴上的飞轮惯量。

基于新型MRTD模型研究扫描型红外热像仪的视距

基于新型MRTD模型研究扫描型红外热像仪的视距张鹏;吴平;贾全涛;曾辉【摘要】This paper presents a method for predicting the minimum resolvable temperature difference (MRTD) of thermal imager based on the perceived threshold signal-to-noise ratio of the human visual system. According to the frequency spectrum theory and two-dimensional modulation transfer function of infrared thermal imaging system, combined with the concept of matched filter, the method describes the spatial frequency spectral function of 4 standard bars. After the 4 standard bars are modulated and transferred by the infrared thermal imaging system, the perceived signal-to-noise ratio of the human visual system can be researched by using the spatial frequency spectral function. A new MRTD model based on the perceived threshold signal-to-noise ratio of the human visual system was established. The visual range prediction of thermal imager was achieved based on the MRTD model and visual range model. Simulation results show that the predicted visual range agrees with the experimental data.%基于人眼视觉系统可感知的阈值信噪比,提出预测红外热像仪最小可分辨温差(MRTD)方法.该方法根据频谱理论和红外热成像系统的二维调制传递函数,并结合匹配滤波器的概念,描述4条带标准靶的空间频谱函数.利用此空间频谱函数研究了4条带标准靶经过红外热成像系统的调制传递之后人眼视觉系统的感知信噪比.基于人眼视觉系统可感知的阈值信噪比,建立一个新的MRTD模型.依据此MRTD模型和视距模型,实现红外热像仪视距的预测.仿真结果表明,该方法预测的视距与实验数据有很好的一致性.【期刊名称】《应用光学》【年(卷),期】2011(032)005【总页数】5页(P998-1002)【关键词】红外热成像系统;视距;最小可分辨温差;二维调制传递函数【作者】张鹏;吴平;贾全涛;曾辉【作者单位】南京航空航天大学理学院,江苏南京211100;南京航空航天大学理学院,江苏南京211100;南京航空航天大学理学院,江苏南京211100;南京航空航天大学理学院,江苏南京211100【正文语种】中文【中图分类】TN216引言目前，通常依据MRTD和约翰逊准则对红外热成像系统的视距进行评估［1］。

211050369_分散固相萃取-超高效液相色谱-串联质谱法测定海龙中11_种磺胺类抗菌药物残留

分析测试新成果 (16 ~ 22)分散固相萃取-超高效液相色谱-串联质谱法测定海龙中11种磺胺类抗菌药物残留王小乔1 ，李　坚1 ，许晓辉1 ，李剑勇2 ，吴福祥1 ，张虹艳1 ，潘秀丽1 ，李　赟1（1. 兰州市食品药品检验检测研究院/食品中农药兽药残留监控国家市场监管重点实验室，甘肃兰州　730050；2. 中国农业科学院兰州畜牧与兽药研究所，甘肃兰州　730050）摘要：采用超高效液相色谱串联三重四极杆质谱（UPLC-MS/MS ）技术，建立了测定海龙中11种磺胺类抗菌药物残留量的分析方法. 样品经2%甲酸-乙腈超声提取，增强型脂质去除分散固相萃取净化管（EMR-Lipid dSPE ）净化，采用Waters ACQUITY BEH C 18色谱柱（1.7 µm ，2.1 mm×100 mm ）分离，电喷雾离子源电离，正离子多反应监测模式（MRM ）检测，以含2 mmol/L 乙酸铵-0.1%甲酸的水溶液和含0.1%甲酸的乙腈溶液为流动相进行梯度洗脱，外标法定量. 11种磺胺类抗菌药物在0～30 ng/mL 的质量浓度范围内线性关系良好，相关系数（R 2）均不低于0.995 9，检出限（LOD ）与定量限（LOQ ）分别在0.11～1.30 µg/kg 和0.37～4.40 µg/kg 之间，11种磺胺类抗菌药物在质量浓度为20.0、50.0、100.0 µg/kg 时的三个加标水平的平均回收率为62.5%～118.1%，相对标准偏差为2.1%～9.2%. 方法前处理简便、准确性好，可用于海龙中11种磺胺类抗菌药物残留的快速筛查.关键词：海龙；超高效液相色谱-三重四极杆质谱联用法；磺胺类药物；分散固相萃取；残留量中图分类号：O657. 63 文献标志码：B 文章编号：1006-3757（2023）01-0016-07DOI ：10.16495/j.1006-3757.2023.01.003Determination of 11 Sulfonamide Antibacterial Drug Residues in Syngnathus by Ultra-Performance Liquid Chromatography-Mass Spectrometry Combined with Dispersed Solid Phase ExtractionWANG Xiaoqiao 1， LI Jian 1， XU Xiaohui 1， LI Jianyong 2， WU Fuxiang 1， ZHANG Hongyan 1，PAN Xiuli 1， LI Yun1（1. Lanzhou Institute for Food and Drug Control/Key Laboratory of Pesticides and Veterinary Drugs Monitoringfor State Market Regulation , Lanzhou 730050, China ；2. Lanzhou Institute of Husbandry and Pharmaceutical Sciences of CAAS , Lanzhou 730050, China ）Abstract ：An analytical method for the determination of 11 sulfonamide antibacterial drug residues in Syngnathus by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS/MS) has been established. The samples were extracted by ultrasonication with 2% formic acid-acetonitrile, purified by an enhanced matrix removal lipid-dispersed solid phase extraction (EMR-Lipid dSPE), and separated on a Waters ACQUITY BEH C 18 column (1.7 µm, 2.1 mm×100mm). The analytes were detected by mass spectrometry using the positive electrospray ionization mode under multiple reaction monitoring mode (MRM), with 2 mmol/L ammonium acetate-0.1% formic acid in aqueous solution and 0.1%收稿日期：2022−10−19；　修订日期：2023−01−08.基金项目：甘肃省市场监督管理局科技计划资助项目（SSCJG-SP-A202204）作者简介：王小乔（1973−），女，本科，研究方向：食品药品检验检测与研究，E-mail ：通信作者：李坚（1969−），男，本科，主管药师，研究方向：食品药品检验检测与研究，E-mail ：.第 29 卷第 1 期分析测试技术与仪器Volume 29 Number 12023年3月ANALYSIS AND TESTING TECHNOLOGY AND INSTRUMENTS Mar. 2023formic acid in acetonitrile as mobile phases by a gradient elution program, and quantified by the external standard method. The results showed that the 11 antibacterial sulfonamides had good linearity in the range of 0~30 ng/mL, the correlation coefficient (R2) were all greater than 0.9959, the limit of detection (LOD) and quantitation (LOQ) were in the range of 0.11~1.30 µg/kg and 0.37~4.40 µg/kg, respectively. At three spiked levels of 20.0, 50.0 and 100.0 µg/kg, the spiked average recoveries of the analytes were in the range of 62.5%~118.1%, and the relative standard deviation was 2.1%~9.2%. The method is accurate, straightforward, and is suitable for the rapid screening of 11 sulfonamide antibacterial drug residues in Syngnathus.Key words：Syngnathus；UPLC-MS/MS；sulfonamides；solid phase extraction；residues海龙是一种药用价值很高的动物源性中药材，也是一种水产品，其为刁海龙Solenognathus hardwickii（Gray）、拟海龙Syngnathoidesbiaculeatus （Bloch）或尖海龙Syngnathus acus Linnaeus的干燥体[1-4]，主要成分是甾体类、脂肪酸、蛋白质、氨基酸、微量元素等，具有温肾壮阳、散结消肿等功效，广泛应用于临床治疗中[5]. 因野生海龙资源稀缺，市场所见海龙主要来源于人工养殖. 在海龙养殖过程中，养殖户为了避免其受细菌感染而造成经济损失，常使用磺胺类药物进行预防治疗. 但有些不良养殖户违规超量使用磺胺类药物，导致药物残留在海龙体内，人类通过食用海龙进而转移到人体内[6-8]. 人类若食用磺胺类药物残留量较高的海龙，易产生药物蓄积，导致肾毒性与过敏反应，甚至会破坏胃肠道菌群平衡，引起白细胞减少等[9-10]. 当前，有关海龙中磺胺类抗菌药物残留量的常规监测未见文献报道，因此，从安全角度出发，很有必要建立简便、可靠的方法以满足海龙中磺胺类药物残留检测的需求.目前，测定动物源性食品中磺胺类药物应用最广泛的是超高效液相色谱-串联质谱法，其具有背景干扰少、灵敏度高、特异性强、选择性强等特点，适合复杂基质中微量成分的检测. 前处理方法应用最广泛的是分散固相萃取和固相萃取柱[11-14]. 传统的分散固相萃取难以去除动物源性食品中大部分脂质干扰物，固相萃取柱因需要活化、淋洗、洗脱和浓缩等，试验过程繁琐. 而增强型脂质去除分散固相萃取（enhanced matrix removal lipid-dispersed solid phase extraction，EMR-Lipid dSPE）可选择性去除样品中的主要脂类且不影响目标分析物的提取效率，相比传统的分散固相萃取和固相萃取柱，EMR-Lipid dSPE具有操作简单、杂质净化高效的优势.为了监测与评判海龙中磺胺类药物残留的暴露水平与风险，本研究采用2%甲酸-乙腈提取干燥样品中的目标待测物，使用EMR-Lipid dSPE净化技术去除脂类等非极性杂质，建立了一种基于超高效液相色谱质谱联用法同时测定海龙中11种磺胺类抗菌药物残留量的分析方法. 该方法快速简单、重复性好、定量准确，适用于海龙中磺胺类药物残留的风险监测.1　试验部分1.1　仪器与试剂Agilent 1290 Infinity II-6460C超高效液相色谱串联三重四极杆质谱联用仪（配置离子源为Agilent Jet Stream电喷雾离子源）、EMR-Lipid dSPE净化管（美国安捷伦科技有限公司）；MS105DU型电子天平（瑞士梅特勒托利多有限公司）；VXR涡旋混合器（德国艾卡仪器设备有限公司）；H1850离心机（湖南湘仪实验室仪器开发有限公司）；SB-800DT超声波清洗机（宁波新芝生物科技股份有限公司）.乙腈（色谱纯，德国默克公司）；乙酸铵、甲酸（色谱纯，日本东京化成工业株式会社）；蒸馏水（广州屈臣氏食品饮料有限公司）；其余试剂均为分析纯. 对照品：磺胺甲基嘧啶（批号：G982705，纯度：99.1%）、磺胺甲噁唑（批号：G150000，纯度：99.5%）、磺胺氯哒嗪（批号：G119228，纯度：99.1%）、磺胺邻二甲氧嘧啶（批号：G151421，纯度：99.1%）、磺胺噻唑（批号：G980077，纯度：99.2%）、磺胺间二甲氧嘧啶（批号：G122608，纯度：99.5%）、磺胺甲二唑（批号：G974370，纯度：99.3%）、磺胺甲氧哒嗪（批号：G150001，纯度：99.7%）均来源于德国Dr.Ehrenstorfer GmbH公司；磺胺嘧啶（批号：100026-201404，纯度：99.7%）、磺胺二甲嘧啶（批号：100411-200501，纯度：100%）来源于中国食品药品检定研究院；磺胺间甲氧嘧啶（批号：97864，纯度：99.1%）来源于曼哈格生物科技有限公司. 实际检测样品的信息如下：甘肃第 1 期王小乔，等：分散固相萃取-超高效液相色谱-串联质谱法测定海龙中11种磺胺类抗菌药物残留17中医药大学附属医院2批（批号：20141101）；广西蓝正药业有限责任公司2批（批号：200901）；甘肃陇脉药材有限公司1批（批号：190701）.1.2　对照品溶液配制精密称取11种磺胺类药物对照品10.0 mg，分别置于10 mL棕色容量瓶中，加适量乙腈并超声使其溶解，取出放至室温，使用乙腈稀释至刻度，摇匀，得到质量浓度均为1 mg/mL的对照品储备溶液，于−18 ℃下保存备用. 分别准确吸取上述各对照品储备溶液0.025 mL，置于同一个25 mL的棕色容量瓶中，使用乙腈稀释至刻度，摇匀，得到质量浓度均为1 µg/mL的混合对照品中间溶液，于−18 ℃下保存备用. 再精密移取1.00 mL上述混合对照品中间溶液，置于10 mL棕色容量瓶，用乙腈稀释至刻度，摇匀，得到质量浓度均约为100 ng/mL的磺胺类药物混合对照品溶液，于4 ℃冷藏备用.1.3　供试品溶液配制取适量供试样品，粉碎，精密称取1 g，置于50 mL容量瓶中，加入2 mL水复原，静置20 min，精密加入10.00 mL 2%甲酸-乙腈，涡旋振荡2 min，超声处理20 min，再加入4 g硫酸钠和1 g氯化钠，涡旋振荡2 min，在3 900 r/min转速下离心15 min，精密移取上层清液2.00 mL置于EMR-Lipid dSPE 净化管，涡旋振荡1 min，在3 900 r/min转速下离心20 min，取上层清液，过0.22 µm有机滤膜，上机测定.1.4　色谱条件色谱柱：Waters ACQUITY BEH C18色谱柱（1.7µm，2.1 mm×100 mm）. 流动相：A相为含2 mmol/L 乙酸铵和0.1%甲酸的水溶液，B相为含0.1%甲酸的乙腈溶液，梯度洗脱程序如下：0~1.0 min，15% B；1.0~2.0 min，30% B；2.0~3.0 min，40% B；3.0~4.5 min，90% B；4.5~6.5 min，90% B；6.5~7.0 min，15% B；7.0~8.0 min，15% B. 柱温：35 ℃；进样量：2 µL；流速：0.2 mL/min.1.5　质谱条件离子源：安捷伦喷射流电喷雾离子源（agilent jet stream electron spray ionization，AJS ESI）；离子极性：正离子；采集模式：多反应监测模式（multiple reaction monitoring，MRM）；气流温度：325 ℃；雾化气：N2；干燥气流速：6 L/min；雾化器压强：0.31 MPa；鞘气流速：10 L/min；鞘气温度：350 ℃；毛细管电压：4 000 V；各个磺胺类药物的质谱参数及保留时间如表1所列.2　结果与讨论2.1　前处理条件选择本试验检测的11种磺胺类药物在甲醇、乙腈中均能够很好的溶解，大多数被测目标化合物与乙腈极性接近，且乙腈能变性并沉淀蛋白，故选择乙腈作为海龙中磺胺类药物的提取溶剂. 由于磺胺类药物在酸性条件下容易发生质子化，酸化提取溶剂表 1 11种磺胺类药物的质谱参数及保留时间Table 1　Mass spectrum parameters and retention times of 11 sulfonamides序号名称保留时间/min母离子/（m/z）子离子/（m/z）碎裂电压/V碰撞能量/eV 1磺胺甲噁唑 4.665254.1156.0*/108.010010/25 2磺胺氯哒嗪 4.449285.0156.0*/108.010010/25 3磺胺间甲氧嘧啶 4.006281.1156.0*/108.010515/25 4磺胺甲基嘧啶 3.607265.1172.0/156.0*11012/15 5磺胺邻二甲氧嘧啶 4.585311.1156.0*/92.012015/30 6磺胺间二甲氧嘧啶 5.067311.0156.0*/108.013020/26 7磺胺二甲嘧啶 3.950279.1186.1*/156.112015/16 8磺胺嘧啶 2.902251.1156.0*/108.010010/22 9磺胺甲二唑 3.969271.0156.0*/108.09010/22 10磺胺噻唑 3.208256.0156.0*/108.010010/21 11磺胺甲氧哒嗪 4.287281.1156.0*/108.010515/25注：“*”为定量离子18分析测试技术与仪器第 29 卷有助于目标物的提取，本试验考察了在10 ng/mL 加标质量浓度下，乙腈、1%甲酸-乙腈、2%甲酸-乙腈、5%甲酸-乙腈的提取回收率和质谱响应. 结果发现，11种磺胺类药物在甲酸酸化乙腈中的质谱响应优于乙腈，当提取溶剂为2%甲酸-乙腈时，大部分磺胺类药物的质谱响应及提取回收率都优于其他甲酸酸化方案（如图1所示）. 而EMR-Lipid dSPE 是一种新型分散固相萃取技术，常被用在QuEChERS 和蛋白质沉淀等净化流程中，可有效去除海龙中非极性的基质杂质，能够提高基质去除效率和分析重现性，与传统分散固相萃取相比，提高了净化效果.与固相萃取柱相比，净化流程简单快速，无繁琐的活化、上样、淋洗以及洗脱等步骤. 因此本试验最终采用2%甲酸-乙腈提取样品中目标待测物，EMR-Lipid dSPE 净化.2.2　色谱及质谱条件优化磺胺类药物含有相同的母体结构，在酸性条件下容易发生质子化，本试验选用了通用型超高效色谱柱Waters ACQUITY BEH C 18. 在正离子多反应监测采集模式下，流动相中加入适量甲酸能提高电喷雾源对目标检测物的离子化效率，加入适量乙酸铵能减少拖尾并改善峰形，因此选择在乙腈与水中加入不同浓度的甲酸、乙酸铵，考察峰形对称性、灵敏度与分离效果，寻找最佳流动相组合. 结果表明，在水相中加入2 mmol/L 乙酸铵和0.1%甲酸能显著改善峰形、提高灵敏度，在有机相中加入0.1%甲酸能提高离子化效果与重现性，稳定保留时间. 因此本试验采用含2 mmol/L 乙酸铵与0.1%甲酸的水溶液、含0.1%甲酸的乙腈作为流动相.分别将对照品溶液直接注入质谱仪，在正离子采集模式下，以全扫描（Scan ）确定化合物准分子离子. 以选择离子扫描（Sim ）确定碎裂电压，以子离子扫描（Product ion ）确定丰度最高的2个子离子，分别作为定性离子与定量离子. 以多反应监测扫描（MRM ）确定定性离子与定量离子的最佳碰撞能量，建立的仪器采集方法包含化合物名称、定性定量离子对、碰撞能量、碎裂电压以及驻留时间等.以多反应监测模式采集11种磺胺类抗菌药物的定性、定量离子对色谱图，其质量浓度为20ng/mL 的混合对照品溶液的提取离子流图如图2所示. 由图2可见，各个目标检测物监测通道互不干扰，所得采集峰形对称且响应良好.2.3　基质效应基质效应影响测定结果的准确性，因此，评价基质产生的基质效应十分有必要. 本试验通过考察同一浓度的空白样品基质溶液匹配混合对照品溶液，与2%甲酸-乙腈匹配混合对照品溶液质谱响应强度比值的百分比来评价基质效应（matrix effect ，ME ）. ME 为（100±20）%，通常认为ME 弱. ME 大于120%或小于80%，分别为存在增强或抑制效应.如图3所示，磺胺间二甲氧嘧啶存在弱的增强效应，磺胺噻唑存在抑制效应，除此之外，其他目标检测物的基质效应较弱. 总体来说，基质效应不影响所有目标检测物的分析结果.2.4　方法学考察2.4.1　线性关系、检出限和定量限使用乙腈将混合对照品溶液依次稀释配制成质量浓度为0、1、2、5、10、20、30 ng/mL 的标准曲线磺胺间甲氧嘧啶磺胺甲噁唑回收率/%乙腈1% 甲酸乙腈2% 甲酸乙腈5% 甲酸乙腈140120100806040200磺胺氯哒嗪磺胺甲基嘧啶磺胺邻二甲氧嘧啶磺胺甲氧哒嗪磺胺间二甲氧嘧啶磺胺二甲嘧啶磺胺嘧啶磺胺甲二唑磺胺噻唑图1　不同提取溶剂的提取效率Fig. 1　Extraction efficiencies of different extraction solvents第 1 期王小乔，等：分散固相萃取-超高效液相色谱-串联质谱法测定海龙中11种磺胺类抗菌药物残留19溶液，外标法定量，以11种磺胺类药物的浓度（x ）为横坐标，以定量离子的响应值（y ）为纵坐标，绘制标准曲线. 取空白样品，逐级减少加入混合对照品溶液，按1.3项下方法处理样品，上机测定. 由提取的MRM 色谱图，以信噪比为3对应的质量浓度作为检出限（LOD ），以信噪比为10对应的质量浓度作为定量限（LOQ ），结果如表2所列. 由表2可见，11种目标检测物在0～30 ng/mL 的质量浓度范围内，线性关系良好，相关系数R 2不低于0.995 9，LOD 为0.11～1.30 µg/kg ，LOQ 为0.37～4.40 µg/kg.2.4.2　回收率与精密度选用海龙空白样品，分别添加20.0、50.0、100.0µg/kg 3个浓度水平的混合对照中间液，按照前处理方法处理后上机测定，每个浓度水平平行进行6次试验，每份待测样品溶液重复测定2次，计算回收率与精密度（RSD ），结果如表3所列. 由表3可见，11种目标待测物的平均回收率为62.5%～118.1%，RSD （n=6）为2.1%～9.2%，建立的分析方法完全能够满足实际样品的检测需求.2.5　样品测定采用本方法对5批海龙样品中11种磺胺类抗菌药物残留量进行测定，结果未检出目标检测物，如图4所示（其中1批阴性样品总离子流图），说明市售海龙中上述11种磺胺类抗菌药物残留在一定程度上处于低风险等级.3　结论本研究采用2%甲酸-乙腈作为提取溶剂，超声提取样品中目标待测物，EMR-Lipid dSPE 净化提取液，以正离子多反应监测模式检测，同时优化了液相色谱质谱检测条件，建立了一种超高效液相色谱质谱联用法同时测定海龙中11种磺胺类药物残留的分析方法，并进行了相关的方法学考察. 该方法具有线性关系良好、灵敏度高、准确度和精密度好的特点，且前处理简单、净化高效. 基质效应评价显示，虽然目标检测物存在不同程度的基质效应，但磺胺甲噁唑磺胺氯哒嗪磺胺间甲氧嘧啶磺胺甲基嘧啶磺胺邻二甲氧嘧啶磺胺甲氧哒嗪磺胺间二甲氧嘧啶磺胺二甲嘧啶磺胺嘧啶磺胺甲二唑磺胺噻唑2.0×103C o u n t s1.8×1031.6×1031.4×1031.2×1031.0×1030.8×1030.6×1030.4×1030.2×10300.81.2 1.62.0 2.4 2.83.23.64.44.0Acquisition time/min4.85.2 5.66.0 6.4 6.87.27.68.0图2　11种磺胺类药物对照品提取离子流图Fig. 2　Extract ion chromatogram of 11 standards of sulfonamides磺胺间甲氧嘧啶磺胺甲噁唑回收率/%140120100806040200磺胺氯哒嗪磺胺甲基嘧啶磺胺邻二甲氧嘧啶磺胺甲氧哒嗪磺胺间二甲氧嘧啶磺胺二甲嘧啶磺胺嘧啶磺胺甲二唑磺胺噻唑图3　11种磺胺类药物的基质效应Fig. 3　Matrix effects of 11 sulfonamides20分析测试技术与仪器第 29 卷不影响分析结果，符合准确定性定量要求. 该方法适用于海龙中磺胺类抗菌药物残留量的检测，可为监控海龙中磺胺类抗菌药物残留风险提供技术支撑.参考文献：国家药典委员会. 中华人民共和国药典(一部2020版)[M ]. 北京: 中国医药科技出版社, 2020:306.［ 1 ］吴伟建, 王燕, 王斌, 等. 基于聚类、主成分和判别分析的海龙红外指纹图谱研究[J ]. 中国药学杂志，2013，48（18）：1540-1545. [WU Weijian, WANG Yan, WANG Bin, et al. Infrared fingerprint analysis of syngnathus' s ethanol extracts coupled with cluster［ 2 ］表 2 11种磺胺类药物的线性关系、检出限、定量限Table 2　Linear relationship, LOD, LOQ of 11 sulfonamides序号名称线性方程R2线性范围/（ng/mL ）LOD/（µg/kg ）LOQ/（µg/kg ）1磺胺甲噁唑y =139.010x +28.158 70.995 90～300.48 1.602磺胺氯哒嗪y =107.763x +15.615 70.997 90～300.84 2.803磺胺间甲氧嘧啶y =171.804x +35.380 50.998 50～300.73 2.404磺胺甲基嘧啶y =141.980x +7.901 70.998 60～30 1.30 4.405磺胺邻二甲氧嘧啶y =1 038.220x +227.398 00.998 10～300.110.376磺胺间二甲氧嘧啶y =596.926x +90.787 30.998 60～300.38 1.307磺胺二甲嘧啶y =325.171x +42.142 30.998 80～300.170.548磺胺嘧啶y =146.238x +62.685 00.999 20～300.220.709磺胺甲二唑y =120.498x -3.966 50.999 20～300.95 3.1010磺胺噻唑y =117.540x +14.036 40.999 50～300.320.9711磺胺甲氧哒嗪y =165.395x+35.380 50.998 50～300.762.50表 3 11种磺胺类药物的回收率及RSD （n=6）Table 3　Recoveries and RSD of 11 sulfonamides 序号名称20.0 µg/kg50.0 µg/kg100.0 µg/kg加入质量/ng测得质量/ng 平均回收率/%RSD/%加入质量/ng 测得质量/ng 平均回收率/%RSD/%加入质量/ng测得质量/ng 平均回收率/%RSD/%1磺胺甲噁唑20.6814.0868.19.251.7038.8875.2 4.3103.4082.4179.7 3.92磺胺氯哒嗪21.7618.5485.27.754.4046.5185.5 3.7108.8088.4581.3 2.63磺胺间甲氧嘧啶21.6816.1974.7 4.854.2052.4696.8 3.2108.4083.3676.9 2.44磺胺甲基嘧啶22.0416.1873.4 3.855.1042.8777.8 6.9110.2085.0777.2 6.55磺胺邻二甲氧嘧啶21.7018.4485.0 2.754.2547.6887.9 3.0108.5098.0890.4 2.66磺胺间二甲氧嘧啶21.8219.7290.4 4.554.5555.80102.3 2.5109.10118.05108.22.17磺胺二甲嘧啶21.7621.3798.23.054.4053.9199.1 3.4108.80108.0499.3 2.88磺胺嘧啶22.7617.4176.5 4.656.9045.6380.2 5.8113.8084.8974.6 4.39磺胺甲二唑21.0024.42116.3 6.952.5062.00118.1 3.1105.00116.02110.54.710磺胺噻唑20.8013.0062.55.052.0032.9263.3 4.9104.0065.2162.76.011磺胺甲氧哒嗪22.5215.6769.64.356.3037.1065.92.9112.6074.6566.34.31.2×1031.0×1030.8×1030.6×1030.4×1030.2×1031.02.03.04.0Acquisition time/minC o u n t s5.06.07.08.0图4　阴性样品总离子流图Fig. 4　Total ion chromatogram of negative sample第 1 期王小乔，等：分散固相萃取-超高效液相色谱-串联质谱法测定海龙中11种磺胺类抗菌药物残留21analysis, principal component analysis and discrimin-ant analysis [J ]. 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Progress in the risk sources and assessment of aquatic products in China [J ]. Food Science ，2015，36 （17）：300-304.]［ 10 ］周瑞铮, 陈锦杭, 张树权, 等. 分散固相萃取结合液相色谱-串联质谱法测定淡水鱼中9种磺胺类和3种喹诺酮类药物残留量[J ]. 食品安全质量检测学报，2021，12（17）：6946-6952. [ZHOU Ruizheng, CHEN Jinhang, ZHANG Shuquan, et al. Determination of 9kinds of sulfonamides and 3 kinds of quinolones residues in freshwater fish by dispersive solid phase extraction coupled with liquid chromatography-tan-dem mass spectrometry [J ]. Journal of Food Safety &Quality ，2021，12 （17）：6946-6952.]［ 11 ］覃玲, 董亚蕾, 王钢力, 等. 分散固相萃取-液相色谱-串联质谱法测定常见动物源性食品中42种兽药残留[J ]. 色谱，2018，36（9）：880-888. [QIN Ling,DONG Yalei, WANG Gangli, et al. Determination of 42 veterinary drug residues in common animal de-rived food by dispersive solid phase extraction coupled with liquid chromatography-tandem mass spectro-metry [J ]. Chinese Journal of Chromatography ，2018，36 （9）：880-888.]［ 12 ］余丽梅, 张聪, 宋超, 等. 分散固相萃取-超高液相色谱/质谱测定水产品中磺胺类抗生素的残留量[J ].中国农学通报，2017，33（26）：128-135. 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Chem.Soc.Rev.,2012,41,7938–Defect-related luminescent materials

Cite this:Chem.Soc.Rev .,2012,41,7938–7961Defect-related luminescent materials:synthesis,emission properties and applicationsCuimiao Zhang ab and Jun Lin*aReceived 25th March 2012DOI:10.1039/c2cs35215jLuminescent materials have found a wide variety of applications,including information displays,lighting,X-ray intensiﬁcation and scintillation,and so on.Therefore,much eﬀort has been devoted to exploring novel luminescent materials so far.In the past decade,defect-related luminescent materials have inspired intensive research eﬀorts in their own right.This kind of luminescent material can be basically classiﬁed into silica-based materials,phosphate systems,metal oxides,BCNO phosphors,and carbon-based materials.These materials combine several favourable attributes of traditional commercially available phosphors,which are stable,eﬃcient,and less toxic,being free of the burdens of intrinsic toxicity or elemental scarcity and the need for stringent,intricate,tedious,costly,or ineﬃcient preparation steps.Defect-related luminescentmaterials can be produced inexpensively and on a large scale by many approaches,such as sol–gel process,hydro(solvo)thermal reaction,hydrolysis methods,and electrochemical methods.This review article highlights the recent advances in the chemical synthesis and luminescent properties of the defect-related materials,together with their control and tuning,and emission mechanisms (solid state physics).We also speculate on their future and discuss potential developments for their applications in lighting and biomedical ﬁelds.1.IntroductionLuminescent materials (or phosphors)are generally characterized by the emission of light in the visible range but can also be in other spectral regions (such as ultraviolet or infrared)with energy beyond thermal equilibrium.1,2The ever-growing demand for advanced luminescent materials has motivated scientiﬁc andaState Key Laboratory of Rare Earth Resources Utilization,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022,P.R.China.E-mail:jlin@;Fax:(+86)431-85698041bCollege of Chemistry and Environmental Science,Hebei University,Baoding 071002,P.R.China.E-mail:cuimiaozhang@Cuimiao ZhangCuimiao Zhang was born in Hebei,China,in 1980.She received her BS (2004)in chemistry from Hebei Univer-sity.Then she has been a grad-uate student in Jun Lin’s group at Changchun Institute of Applied Chemistry (CIAC),Chinese Academy of Sciences,and received a PhD degree in 2010.After graduation,she has been working as a research fellow in Nanyang Technolo-gical University (Singapore,2010–2012).Her current research interests include thesynthesis of environmentally-friendly luminescence materials and their bioapplication.She came back to China in 2012,and since then has been working as an assistant professor in Hebei University.Jun LinJun Lin was born in Chang-chun,China,in 1966.He received BS and MS degrees in inorganic chemistry from Jilin University,China,in 1989and 1992,respectively,and a PhD degree (inorganic chemistry)from the Chang-chun Institute of Applied Chemistry (CIAC),Chinese Academy of Sciences,in 1995.Then he went to CityU (HK,1996),INM (Germany,1997),VCU and UNO (USA,1998–1999)working as a postdoctor.He came back toChina in 2000,and since then has been working as a professor in CIAC.His research interests include luminescent materials and multifunctional composite materials together with their applica-tions in display,lighting and biomedical ﬁelds.Chem Soc RevDynamic Article Links/csrCRITICAL REVIEWP u b l i s h e d o n 27 S e p t e m b e r 2012. D o w n l o a d e d o n 06/01/2015 10:49:26.View Article Online / Journal Homepage / Table of Contents for this issuetechnological eﬀorts dedicated to improving existing phos-phors and to developing new eﬀective luminescent materials.3Generally,inorganic luminescent materials can be classiﬁed into two groups:metal-activator based and non-activator based luminescent materials.The ﬁrst case is represented by transitions between energy levels of metal activator ions containing the rare earth and/or transition metal ions (e.g.f–f transitions of Eu 3+in Y 2O 3:Eu 3+)4–7or complex ions (e.g.the charge-transfer transition on [WO 4]2Àin CaWO 4).8,9These kinds of luminescent materials are often expensive and contain non-environmentally friendly elements,such as Ag (in ZnS:Ag +)and lanthanides.1–15On the other hand,it is necessary for most metal-activator-based phosphors to be excited by short-wavelength ultraviolet (UV)light for operation,which results in the extensive use of a mercury vapor plasma in ﬂuorescent lighting products.1,10The excess usage of mercury vapor will give rise to environmental contamination and technical diﬃculties.The other group of luminescent materials consists of semiconductors and defect-related materials.For most semiconductors,the luminescence normally results from band-to-band excitation between impurity states within the bandgap.However,some serious intrinsic toxicity and potential environmental hazards associated with many of these semiconductors are critically pronounced,which have limited their applications.For the defect-related luminescent materials,although the roots can be traced to 1986,16they have had a remarkable growth since Sailor et al.reported the white phosphors from a silicate-carboxylate sol–gel precursor.17Since then,the emerging defect-related luminescent materials,which do not contain any transition metal or rare earth activators,appear to be promising alternatives to traditional phosphors in many applications because of their advantages of low toxicity,stability,tunable emission color,and low cost.17–30Although the origins of photoluminescence (PL)are not yet entirely understood in defect-related materials,there is mounting evidence that emission arises from the special defects.Typically,the defects in these kind of materials contain vacancies,impurities,radical impurities,donor–acceptor pairs,etc.,22,27,31–33which may arouse charge imbalances at these defect sites.The charge imbalances must be rectiﬁed by localization of electrons and electron holes or give rise to impurity states within the bandgap.Therefore,the defect sites are apparently the precursors for various centers containing the emission center for defect-related luminescent materials and impart them with excellent photo-luminescent emission.On the other hand,in modern chemistry and materials science,there have been tremendous developments in the synthetic control of size,shape,and composition,thus allowing the tailoring of their properties.34–40Therefore,the synthesis methods have been inten-sively pursued for their technological and fundamental scientiﬁc importance.41,42Among them,the luminescence properties of defect-related luminescent materials can also be inﬂuenced by their phase,surface chemistry,size distribution,morphology and/or porosity.43–45Thus,the rational control over these factors has become an important research issue in recent years.46So far,valuable explorations have been carried out based on soft chemical synthetic strategies [such as Pechini sol–gel (PSG)method,hydro-thermal process,and so on]to luminescent materials as well as controlled morphologies,formation,and luminescence properties.As we know,the tremendous recent advances in functionalized nanomaterials with distinct ﬂuorescent properties,47–54mesoporous properties,55and biocompatability 56,57have received considerable attention in the past decades,since nanomaterials provide a new platform for biomedical applications such as drug delivery,bio-separation,ﬂuorescent labeling,58diagnosis and treatment of disease.59–68During the past decades,the use of semiconductor ﬂuorescent nanocrystals or quantum dots has notably extended the scope of possible biological applications (ﬂuorescent probes,labeling and tracking,etc.)due to their high quantum yield and high photostability.69,70However,their disadvantages of blinking,potential cytotoxicity in vivo ,and complex functionalization strategies have limited their use.Additionally,some serious problems of photobleaching and quenching of ﬂuorescent organic molecules are critically pronounced,which have seriously limited their applications in biomedical areas.60,71,72In contrast to traditional ﬂuorescent materials in biological areas such as organic dyes and quantum dots,the novel defect-related luminescent nanomaterials may be promising ﬂuorescent materials in biological ﬁelds due to their good optical properties,high chemical stability,and low toxicity.29,30,73–77Especially,multifunctional defect-related materials with excellent luminescent,structural,and/or surface properties seem to be ideal systems for biomedical applications.To date,many recent reports have shown that multifunctional defect-related materials,as the most eﬃcient ﬂuorescent materials,can be used for the intracellular imaging,drug delivery,and so on.26,29,30,78In this review article,we mainly focus on the recent progress in various chemical syntheses and luminescent properties of defect-related luminescent materials,together with their tuning and possible emission mechanisms as well as their applications in lighting,display,and biological ﬁelds (including bioimaging and tracking in drug delivery systems),based on our recent eﬀorts and those of others in this area.Moreover,we hope to inspire research into the origins of the unique properties of this emergent class of novel luminescent materials and to encourage their exploration in a multitude of exciting areas from lighting to display and medical diagnostics.2.Synthetic methodsGenerally,as the defect sites are mainly created in the preparing process,the luminescent properties of defect-related materials seem to be dominated by the preparation methods.In recent years,a large number of synthetic methods have been developed for generating defect-related luminescent materials.These methods can be divided into several categories:sol–gel method,hydro-(solvo)thermal reaction,hydrolysis method,electrospinning process,sonochemical synthesis,chemical vapor deposition (CVD),and so on.Typically,the common features of all these methods of synthesis are the need of heat treatments (high or low temperature)and/or organic groups (surfactants,organic additives,templates,etc.).2.1.Sol–gel methodUndoubtedly,the sol–gel technique is one of the most well-known soft solution processes,which can be generally divided into three types:sol–gel route based on the hydrolysis andP u b l i s h e d o n 27 S e p t e m b e r 2012. D o w n l o a d e d o n 06/01/2015 10:49:26.condensation of molecular precursors,gelation route based on concentration of aqueous solutions containing metal-chelates (called ‘‘chelate gel’’route),and polymerizable complex route (named Pechini-type sol–gel process).79–81Commonly,silicon alkoxides,metal alkoxides,or organic additives [such as citric acid and polyethylene glycol (PEG)]are employed in the sol–gel process,following heat treatment to remove the organic groups produced by alcoholysis of alkoxides or organic additives.Interestingly,it is also possible to utilize some defects (such as carbon impurities and vacancies)as emission centers to get novel defect-related luminescent materials.17,79It has been reported that sol–gel-derived SiO 2-based materials,including silica gels (xerogels or aerogels),28,82porous silica,83multicomponent silica-based oxide materials,84silicate-carboxylate,17and inorganic–organic hybrids,18,85all show strong luminescence from the blue to red spectral region,17–19,27and even ultraviolet photoluminescence.83They can potentially be used as environ-mentally friendly luminescent materials without expensive or toxic metal elements as activators.Pechini-type sol–gel process (PSG),which uses common metal salts as precursors,citric acid as a chelating ligand of metal ions and polyhydroxy alcohol as a cross-linking agent to form a polymeric resin on the molecular level,can reduce segregation of particles and ensure compositional homogene-ity.These advantages can overcome most of the diﬃculties and disadvantages that frequently occur in the alkoxide-based sol–gel process (high cost,fast hydrolysis rate,and so on).Pechini-type sol–gel method followed by heat treatment at moderate temperature can remove organic additives and generate a pure phase of multiple components (Scheme 1).79During this annealing process,hydrocarbon residues cannot be removed completely,which may induce carbon impurities and form other kinds of defects in the host lattice (such as the oxygen defects).It is possible to utilize these defects as emission centers to obtain novel phosphors without rare earth or transition metal ions as activators.In the past several years,our group has synthesized various kinds of highly eﬃcient defect-related phosphors by PSG.We found that the PSG process-derived BPO 4exhibits a weak purple-colored emission under UV irradiation caused by the carbon impurities.Doping it with alkaline earth metal and alkali metal ions 86,87or mixing with SiO 2or Al 2O 388produced a series of BPO 4-based materials that emit an eﬃcient bluish-white light with a quantum yield more than 31%,which is induced by carbon impurities,peroxyl radicals,and/or oxygen vacancies defects,respectively.Besides BPO 4-based phosphors,the same phenomena were also observed in Al 2O 3,89ZrO 2,43and silica/apatite composite 90prepared by PSG process (Fig.1),whichcan also show eﬃcient,stable,and/or tunable luminescence.In addition,some titanates (CaTiO 3,SrTiO 3,and BaTiO 3)exhibiting an intense photoluminescence were also prepared by PSG method followed by calcination at 300–4001C.91,92For the sol–gel method,the annealing procedure (temperature and annealing time)is the key step in the synthesis process,which can seriously aﬀect the types and quantities of the defects in the materials and their luminescent properties.2.2.Hydro(solvo)thermal reactionIt is well known that the hydrothermal method is a typical solution-based method that exploits water or organic solvents under certain temperatures and pressures,and has received much attention.93Over the past decade,various micro-and/or nano-crystals,which exhibit many interesting shape-and size-dependent phenomena and properties,have been synthesized by the hydrothermal process and extensively investigated for both their scientiﬁc and technological applications.94–99Especially,the water-based systems with environmentally acceptable and relatively low cost advantages provide a relatively green chemical alternative to the preparation of various inorganic materials.38,100–102To date,diﬀerent defect-related luminescentScheme 1Basic principle of Pechini sol–gel process to synthesize phosphors (reproduced with permission from ref.79,copyright 2007,American Chemical Society).Fig.1Representative shapes of defect-related luminescent materials obtained by Pechini-type sol–gel process.SEM images of BPO 4:6%Li +(a),Al 2O 3(b),ZrO 2(c)(reproduced with permission from ref.87,89and 43,copyright 2009,2008,and 2007,American Chemical Society),and silica/apatite composite (d)(reproduced with permission from ref.90,copyright 2011,Royal Society of Chemistry).P u b l i s h e d o n 27 S e p t e m b e r 2012. D o w n l o a d e d o n 06/01/2015 10:49:26.materials have been successfully prepared by the simple hydro-thermal method.For instance,based on the hydrothermal treatment at designated reaction conditions (such as reaction temperature and time,chelating ligands,organic additives,etc.),a systematic study has been carried out to investigate the controlled formation of a series of apatite structure micro-/nano-crystals with environmentally friendly defect-related luminescent properties.103–106The general synthetic methodology for the apatite structures is shown in the top of Fig.2.As an example,the hydroxyapatite (HAp)phosphors via hydrothermal process [trisodium citrate as chelating ligands and hexadecyltri-methylammonium bromide (CTAB)as surfactants]with narrow size distribution and novel morphologies and architectures,such as nanorods,nanowires,nanoparticles,microspheres,micro-ﬂowers,microsheets,and microspheres (Fig.2a–f),are of special signiﬁcance in understanding the growth behavior and inﬂuence on defect-related luminescent properties.103Moreover,there are several important key factors for ﬁnal shapes of HAp nano/microcrystals,which contains pH values,organic additive (CTAB),and trisodium citrate (Fig.2).107,108The metal-chelating trisodium citrate ligands can not only aﬀect the morphology of the sample,but also the key factor for the defect-related luminescent properties.During the crystal growth of HAp,the trisodium citrate can slow down the nucleation and subsequent crystal growth of HAp particles and change the relative surface energy of diﬀerent crystal facets,which results in the formation of diﬀerent HAp structures.109On the other hand,the electron paramagnetic resonance (EPR)results indicates that the lumi-nescent-related paramagnetic defects (CO 2 À)can be induced by trisodium citrate during the hydrothermal process.Under the high pressure and thermal process,bond cleavages can occur in some citrate anions,which result in R–C and CO 2 À.Small amounts of CO 2 Àradicals resulting from the bond cleavages are trapped by the already formed hydroxyapatite lattice or interstitial positions.The residual fragmented bonds (CO 2 À)are apparently the precursors for various centers,such as luminescent centers.Apart from the investigation of the HAp nano/microcrystals,we also utilized a similar method to synthesize other apatite structures with defect-related luminescent properties,such as calcium ﬂuorapatite (FAP)nanorods,strontium hydroxyapatite (SrHAp)with various morphologies (nanorods and architecture microspheres).Fig.2g–i shows the representative morpho-logies of FAP and SrHAp products.We found that the molar ratio of metal ions and chelating ligands,reaction time,and acetone treatment are also critical to obtain the apatite structures.Especially,multifunctional strontium hydroxy-apatite nanorods with luminescent and mesoporous properties can be easily synthesized at a low temperature,and have good biocompatibility,stability,nontoxicty,and water-soluble properties.106In addition,the defect-related ﬂuoride materials prepared by the solvothermal method were also reported.97,110The as-obtained alkaline earth metal ﬂuoride (CaF 2,SrF 2,BaF 2)nanocrystals based on the solvothermal method exhibit a narrow size distribution,and can be well dispersed in nonpolar solvents.The colloidal solutions of these three ﬂuoride nano-crystals dispersed in cyclohexane present a strong emissionFig.2The general synthetic methodology for a series of apatite nano/microstructures by hydrothermal method and the typical methodologies for defect-related luminescent apatite structures by hydrothermal method.Typical TEM and SEM images of calcium hydroxyapatite (a–f)(reproduced with permission from ref.103,copyright 2009,American Chemical Society),SEM images of calcium ﬂuorapatite (g)(reproduced with permission from ref.105,copyright 2010,Royal Society of Chemistry),and strontium hydroxyapatite (h,i)(reproduced with permission from ref.106and 104,copyright 2010,2009,Elsevier and American Chemical Society)with multiform shapes.P u b l i s h e d o n 27 S e p t e m b e r 2012. D o w n l o a d e d o n 06/01/2015 10:49:26.band around 400nm in the PL spectra.97In addition,a series of well-dispersed KRE 3F 10(RE =rare earth:Sm–Lu,Y)colloidal nanocrystals with a rich variety of morphologies,such as hexagonal nanoplates,nanocubes and nanoparticles have been synthesized by a facile solvothermal route.The as-prepared nanocrystals are highly crystalline and can be well dispersed in nonpolar solvents such as cyclohexane and chloroform to form stable and clear colloids,which all display self-activated luminescence.1102.3.Hydrolysis methodIt is well known that the hydrolysis method is often used to prepare hydroxide and oxide materials using alkoxides as precursors.Over the past decade,monodisperse nano-/microspheres,which exhibit tunable or size-dependent photoluminescent properties,have been synthesized by the hydrolysis method and extensively investigated.111–115Our group has reported the simple synthesis of nearly monodisperse zirconia spheres (ZrO 2)with defect-related tunable luminescent properties (Fig.3a and b)by the controlled hydrolysis of zirconium butoxide in ethanol,followed by heat treatment in air at low temperature from 300to 5001C.106,116In addition,the well-known Sto ber method,117based on hydro-lysis of tetraethylorthosilicate (TEOS)in an alcohol medium in the presence of water and ammonia,has been extensively employed to prepare the monodisperse silica (SiO 2)spheres with diﬀerent sizes by a modiﬁed procedure (Fig.3).These monodisperse SiO 2spheres could be further annealed at low temperature (generally less than 6001C),and exhibited bright,stable,and tunable defect-related luminescence.111,113Apart from the methodology presented by Sto ber and modiﬁed Sto ber methods,other hydrolysis-related strategies have recently been developed,based mainly on reverse microemulsions using a stable and macroscopically isotropic dispersion of a surfactant and water in a hydrocarbon (Fig.3c),114,118,119or on direct micelles as templates.120,1212.4.Electrospinning processThe electrospinning technique was developed for the synthesis of one-dimensional (1D)nanomaterials.122–128During the synthesis process,the as-synthesized 1D precursor needs to be annealed to remove the organic additives.Moreover,it is also possible to form some carbon-related impurities induced by residual organic additives and other oxygen-related defects as emission centers during the annealing process.Recently,the electrospinning method was employed to prepare multifunctional silica ﬁbers,which possess irregular porous structure,and display ﬁber-like morphology with dimensions of several hundred nanometers in width and several millimeters in length (Fig.4).129Furthermore,the as-obtained silica ﬁbers exhibit an intense broad bluish emission,which might be attributed to impurities and/or defects in the silica ﬁbers.In addition,Qiu and co-workers reported tunable emission of BCNO nanoparticle-embedded polymer electrospun nano-ﬁbers.130Firstly,BCNO nanoparticles were prepared by a low-temperature method.Then,the BCNO nanoparticle-embedded polymer electrospun nanoﬁbers were synthesized by an electrospinning process using synthesized BCNO phosphors as raw materials.Photoluminescence properties of these nanoﬁbers indicate that the emission can be readily tuned by adjusting the C concentration in the BCNO phosphors.Fig.3Typical SEM images for unannealed ZrO 2(a),heat-treated ZrO 2spheres (b)(reproduced with permission from ref.112,copyright 2009,American Chemical Society),and (c–f)SiO 2spheres with diﬀerent size (reproduced with permission from ref.114,copyright 2010,Elsevier).Fig.4Typical SEM images of the as-formed precursor (a)and porous silica ﬁbers annealed at 6001C (b).The possible formation process of the porous structures in silica ﬁbers (c)(reproduced with permission from ref.129,copyright 2010,Wiley).P u b l i s h e d o n 27 S e p t e m b e r 2012. D o w n l o a d e d o n 06/01/2015 10:49:26.2.5.Sonochemical synthesisThe sonochemical method has been widely used to prepare a variety of nanostructured materials.131,132During the sonication process,propagation of pressure waves is intense enough to cause the formation,growth and implosive collapse of bubbles in liquid medium.These bubbles generate localized hotspots,which exhibit extreme temperatures,pressure and high cooling rates.133Sonochemical eﬀects can primarily drive a variety of chemical reactions such as oxidation,reduction,and so on.During this special process,some defects can also be formed as a result of localized hotspots.Recently,Uchino and co-workers 134synthesized luminescent silica crystals without luminescent activator ions via a sonochemical reduction route.The neutral oxygen vacancy or the F center induced by the sonochemical process might be the emission centers and give a broad visible PL band peaking at B 500nm under UV irradiation.The sonochemical reduction of TEOS by a colloidal solution of sodium performed by Gedanken’s group led to the formation of silicon.135Ultrasound-induced reduction was further applied to a system with silicon alkoxides and colloidal sodium to prepare luminescent silicon nanoparticles.2.6.Chemical vapor depositionThe chemical vapor deposition (CVD)system is believed as an important synthesis method with several advantages,such as relatively low temperature and low cost,adaptable to a wide variety of structures,rapid growth,and direct growth on a large number of substrates.136Controlling the diﬀerent reaction conditions (such as substrate temperature,pressure,reactant composition,reactant pre-treatment,supply rates,etc.),a number of forms of CVD are in wide use,including atmospheric pressure CVD (APCVD),aerosol-assisted CVD (AACVD),plasma-enhanced CVD (PECVD),and so on.137–139So far,a large number of compounds,including oxides,sulﬁdes,semiconduc-tors,carbon-based materials,etc.,have been grown by these CVD methods.140Among them,some defect-related luminescent materials can also be obtained by this kind of method.Previously,oﬀ-stoichiometric silicon oxide (SiO x ,x o 2)thin ﬁlms can often be synthesized via chemical vapor deposition.141,142In addition,Becher’s group reported the ﬂuorescence and polarization spectroscopy of single silicon vacancy centers in heteroepitaxial nanodiamonds on iridium using microwave plasma chemical vapor deposition.143Yang and co-workers have successfully fabricated the In 2O 3–ZnO one-dimensional nanosized heterostructures constructed by In 2O 3quadrangular columns and ZnO hexagonal disks by thermal chemical vapor transport.144Besides the above methods,multistep heat treatment,145thermal decomposition,16ﬂame spray pyrolysis,146microwave irradiation method,147etc.can also be employed to prepare the defect-related luminescent materials.3.Classiﬁcation and optical propertiesDefect-related luminescent materials can be classiﬁed intosilica-based materials,phosphate systems,metal oxides,BCNO phosphors,and carbon-based materials,etc .Here we will elucidate the luminescent properties together with theircontrol and tuning,and emission mechanisms (solid state physics)of these materials.3.1.Silica and silica-based materialsEarlier defect-related luminescent materials were mainly based upon silica and silica-based materials,including silicate-carboxylate,17SiO 2glass,18,22SiO 2gels,27,28SiO 2spheres,111,114organic/inorganic hybrid silicones,23–25silica nanotubes,148molecular sieves,31,149etc.150–156As the most promising materials for environmentally friendly phosphors,these kinds of luminescent materials have been the focus of research eﬀorts since the pioneering work of Sailor and co-workers.17,121It has been reported that a kind of white phosphor with high emissive broadband spectra (Fig.5a)(emission maximum between 450and 600nm)can be synthesized from a sol–gel precursor and a variety of organic carboxylic acid with a low heat treatment.The PL quantum yield of these materials ranged from 20%to 45%under UV (365nm)excitation with PL lifetime less than 10ns.In addition,it is worth pointing out that the bright white photoluminescence was ﬁrst attributed to carbon defect centers and the detailed scheme of the carbon substitutional defect for Si as the luminescent species in the lattice is shown in Fig.5b.Apart from this,silica gels have been also extensively investigated as defect-related phosphors.Among them,silica aerogels,which are well-known to show photoluminescence generally from the blue to red spectral regions,exhibited several structural defects advantageous to photoluminescent properties,such as a non-bridged oxygen hole center (NBOHC)(described as SiOH -SiO + H;this defect was connected with bands at 1.8and 1.9eV),151–153peroxy linkage (POL)(labeled as ROO ,where R represents an unspeciﬁed radical or part of the structure),154and E 0center (R Si )on the basis of the basic emission characteristic band at 2.2eV in the PL spectra.152,156Inaddition,Hinic’s group has reported PL spectra measured Fig.5Optical characterization of SiO 2-based materials.Emission spectra (337nm excitation at 298K)of sol–gel-prepared SiO 2-based phosphors (a)and a scheme of the carbon substitutional defect for Si as the luminescent species in the lattice (b)(reproduced with permission from ref.17,copyright 1997,).Emission spectra of monodisperse SiO 2spheres excited at 300nm (c)and the corresponding photographs (d)under a 365nm lamp (reproduced with permission from ref.111,copyright 2006,American Chemical Society).P u b l i s h e d o n 27 S e p t e m b e r 2012. D o w n l o a d e d o n 06/01/2015 10:49:26.。

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ZIF-67

大学化学Univ. Chem. 2024, 39 (4), 163收稿：2023-08-31；录用：2023-10-16；网络发表：2023-11-15*通讯作者，Email:************.cn基金资助：山东大学青年学者未来计划；山东大学实验室建设与管理研究项目(sy20232204)•专题• doi: 10.3866/PKU.DXHX202308117 ZIF-67/氧化亚铜复合材料的制备及其光增强电催化性能研究 ——推荐一个综合性物理化学实验林猛*，陈涵睿，徐聪聪山东大学化学与化工学院，济南 250100摘要：大学物理化学实验多以经典的基础理论验证性实验为主，自主设计性、综合性实验缺乏。

依托于山东大学化学实验教学中心现有的仪器设备及实验条件，设计了制备钴基金属有机框架/氧化亚铜微纳米复合材料，并研究其光增强电催化析氧性能的综合性物理化学实验。

本实验涉及物质合成、结构成分分析、产品性能表征、实验结果处理等方面，在启发学生发现物质结构与性能之间内在规律的同时，巩固了学生对前期所学理论及实验知识的掌握，调动了学生学习的积极性和主动性，提升了学生解决问题和灵活运用知识的能力。

关键词：综合性物理化学实验；光增强；电催化析氧反应；半导体；ZIF-67中图分类号：G64；O64Preparation and Study of Photo-Enhanced Electrocatalytic Oxygen Evolution Performance of ZIF-67/Copper(I) Oxide Composite:A Recommended Comprehensive Physical Chemistry ExperimentMeng Lin *, Hanrui Chen, Congcong XuSchool of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China.Abstract: University physical chemistry experiments mainly focuse on classical foundational theory verification experiments, with a lack of independent design and comprehensive experiments. Based on the existing instruments and experimental conditions of the Center for Experimental Chemistry Education of Shandong University, a comprehensive physical chemistry experiment was designed to prepare cobalt-based metal-organic framework/copper(I) oxide micro-nano composites and study the photo-enhanced electrochemical oxygen evolution catalytic performance. This experiment involves aspects such as material synthesis, structural characterization, performance evaluation, and result analysis. It not only inspires students to discover the inherent laws between material structure and properties, but also consolidates their previous theoretical and experimental knowledge, mobilizes students’ enthusiasm and initiative in learning, and enhances their ability to solve problems and flexibly apply knowledge.Key Words: Comprehensive physical chemistry experiment; Photo-enhancement;Electrocatalytic oxygen evolution reaction; Semiconductor; ZIF-671 引言物理化学实验是物理化学教学的重要组成部分，它综合了化学领域中各分支学科所需的基本研究方法和实验技能，是培养学生物理化学基本素养和动手能力的重要教学环节，对提升学生的逻辑思维和科研能力具有重要作用[1]。

基于FPGA的Mel倒谱系数提取方法设计与实现

基于FPGA的Mel倒谱系数提取方法设计与实现杨鸿武;张帅;丁朋程【摘要】为了在嵌入式系统中实现参数化语音合成,提出一种在FPGA(field programmable gate array)中通过SOPC(system on programmable chip)系统提取Mel倒谱系数的方法.用SOPC Builder搭建硬件平台,然后在嵌入式Nios Ⅱ处理器中对语音信号做短时傅里叶变换、对数幅度运算、逆傅里叶变换,最后通过牛顿迭代法实现Mel倒谱系数的求解.将Nios Ⅱ处理器得到的Mel倒谱系数通过JTAG接口回传到计算机上,并与MATLAB仿真结果进行比较,结果表明Nios Ⅱ处理器提取的Mel倒谱系数与MATLAB提取的系数结果相同.%A Mel-cepstral coefficients (MCCs) extraction method on FPGA(Field Programmable Gate Array) by using SOPC(System on a Programmable Chip) system for implementing parameter speech synthesis on embedded system was proposed.A hardware platform was established by SOPC Builder.Short Time Fourier Transform (STFT) was firstly performed on input speech signal.Then the results of STFT were transformed by a logarithm calculation.Finally the Mel-cepstral Coefficients (MCCs) were extracted by Newton-Raphson method from the results of inverse fast Fourier transform that is obtained on the results of logarithm transform.The MCCs calculated by Nios Ⅱ processor are then feedback to comput er through JTAG interface for comparing with the simulating results of MATLAB.The results show that the extracted MCCs by Nios Ⅱ are same with the results of MATLAB.【期刊名称】《仪表技术与传感器》【年(卷),期】2017(000)003【总页数】5页(P82-85,89)【关键词】语音合成;现场可编程门阵列(FPGA);可编程片上系统(SOPC);Mel倒谱系数;参数提取【作者】杨鸿武;张帅;丁朋程【作者单位】西北师范大学物理与电子工程学院,甘肃兰州 730070;西北师范大学物理与电子工程学院,甘肃兰州 730070;西北师范大学物理与电子工程学院,甘肃兰州 730070【正文语种】中文【中图分类】TP391语音合成也被称为文语转换，是人机交互领域的重要分支。

扩散序谱(DOSY)实验中扩散系数维数字分辨率的影响

扩散序谱(DOSY)实验中扩散系数维数字分辨率的影响黄俊霖;余亦华【摘要】核磁共振二维扩散序谱(DOSY)实验测定溶液中分子自扩散系数时,扩散系数维的数据点及其数字分辨率直接影响了测定值的精度.在较系统地确定了DOSY 实验本身偏差范围的基础上,本文研究了扩散系数维不同的数字分辨率对测定值的影响,包括其引入偏差的来源以及形成偏差的大小.由于不同的溶液条件下分子扩散系数的改变可直接用于表征分子结构或状态的变化,本文提出的相对数字分辨率与扩散系数相对变化值的直接比较,可直观地表明数字分辨率对扩散系数测定值的影响.【期刊名称】《波谱学杂志》【年(卷),期】2018(035)003【总页数】7页(P287-293)【关键词】液体核磁共振(liquid-state NMR);数字分辨率;扩散序谱(DOSY);自扩散系数【作者】黄俊霖;余亦华【作者单位】华东师范大学物理与材料科学学院,上海市磁共振重点实验室,上海200062;华东师范大学物理与材料科学学院,上海市磁共振重点实验室,上海200062【正文语种】中文【中图分类】O482.53引言核磁共振扩散序谱（Diffusion Ordered Spectroscopy，DOSY）是目前测量液体样品的自扩散系数（D，简称扩散系数）的一个重要的方法，它通过脉冲梯度场（Pulsed Field Gradient，PFG）对溶液中分子的平移运动进行空间编码，在分子的扩散运动（扩散系数D）与梯度场强度g之间建立起明确的数学关系[1]：其中，I表示加上梯度场脉冲之后测得的信号强度；I0是未加梯度场脉冲时测得的信号强度；D为自扩散系数；γ为所观测核的磁旋比；g为梯度场强度；δ为梯度场脉冲宽度；Δ为脉冲序列中一对梯度场脉冲之间的时间，即扩散时间.将实验中不同梯度场强度下测得的谱峰强度 I代入(1)式，通过指数曲线的拟合便可求得D 值.一维谱中的谱峰产生于溶液中相同或不同的分子，通过谱峰积分面积随梯度场强变化拟合出的D值就是其对应的分子在该溶液体系中的扩散系数.与分别拟合出各个谱峰的D值不同，另一种呈现D拟合值的方式是二维DOSY谱[2].二维DOSY图谱中的其中一维是普通的化学位移轴，另一维则是扩散系数轴，相关峰所对应的扩散系数则是从该谱峰的最高点在扩散系数维的投影值（lgD）读出并换算而得，如图1所示.相关峰的产生首先是通过对其化学位移轴上相应数据点的峰强度变化拟合出，再对D值在一个预设的范围内进行反拉普拉斯变换后模拟生成的[2].虽然在一张DOSY谱上能够读取所有谱峰所对应的扩散系数，但是在DOSY图谱的数据处理时有2个人为设置的参数，即扩散系数的取值范围和数据点[3].扩散系数取值范围和数据点决定了该维读数的数字分辨率（数字分辨率 r=扩散系数的取值范围/数据点），而数字分辨率的大小直接影响到 DOSY实验中扩散系数读数的偏差. 图1 乙基苯样品的DOSY实验图谱（CDCl3）Fig. 1 DOSY spectrum of ethylbenzene (CDCl3)如图2所示，这是一张有关DOSY谱上扩散系数维的数据点及其数字分辨率r的示意图，纵坐标表示扩散系数维的取值，每一条虚线即代表该维的一个数据点，两条虚线间的间隔为该维的数字分辨率.当真实的谱峰最高点（lgD）出现在介于相邻的数据点之间时（如图 2中的椭圆形所示），由于数字分辨率的原因，图谱上实际的谱峰最高点会出现在其临近的数据点上（如图2上的矩形所示），因此图谱上扩散系数维设置的数字分辨率r（与扩散系数的取值范围和数据点相关）的设定影响了谱峰最高点读数的准确性，即为扩散系数维读数的最小偏差.当数字分辨率不够高时，有可能成为实验偏差的主要来源.图2 DOSY数字分辨率示意图Fig. 2 Diagram of digital resolution on F1 dimension (diffusional coefficient dimension) of DOSY spectrum从最初的自旋回波序列（Spin Echo，SE）序列[4]到后来的刺激回波（STimulated Echo，STE）序列[5]的衍变，以及纵向涡流延迟（Longitudinal Eddy current Delay，LED）技术[6]和偶极梯度场脉冲对（Bipolar Pulse Pairs，BPP）[7]技术的运用，大大提高了DOSY实验的可重复性和准确性，也大大拓展了DOSY实验的应用范围.DOSY谱中不同扩散速率分子产生的谱峰可以依据它们扩散的快慢沿着扩散系数维展开（谱峰不重叠的情况下），因此被广泛应用于复杂混合物的分析测试[8-10].更多的应用则是将溶液体系中扩散系数的变化用于表征分子间的相互作用[11,12]，包括分子组装[13]、研究药物分子的包裹作用[14-17]以及聚合物分子量的测定等[18].在已发表的用扩散系数变化表征分子间相互作用的研究文献中，扩散系数的相对变化值通常在百分之几十~百分之十几之间[19-21]，也有仅百分之几的变化[22]，但提及扩散系数维的数据点数，以及考虑该维数字分辨率对研究结果的影响的研究并不多见.早期研究DOSY实验方法的文献曾经提及能观察到的扩散系数最小变化值在2%左右[20]，而本文的研究结果表明如果数字分辨率运用得不合适，偏差会远大于 2%（见本文的研究结果与讨论），因此有必要对DOSY图谱扩散系数维数字分辨率的影响做一个较系统的研究，避免由此引起的实验偏差增加.数字分辨率的大小只是DOSY实验结果的偏差来源之一，它源于对实验数据的处理，而实验数据本身也会产生一个偏差范围.为了区分和比较两者的差别，本文首先研究了DOSY实验本身的重复性及偏差范围，继而分析研究了数字分辨率对扩散系数检测值的影响，阐述了实验偏差与数字分辨率的关系.1 实验部分1.1 仪器与测试样品测试仪器为Bruker公司的AvanceⅢ HD谱仪，配有BBFO 5 mm探头，1H核的共振频率为500.13 MHz.Z方向最大梯度场强度为53.5 Gauss/cm.测试样品为Bruker公司提供的标样，即0.1%乙基苯/氘代氯仿（EB/CDCl3）样品.1.2 NMR实验DOSY实验使用Bruker公司的标准脉冲序列stebpgp1s[4]，谱宽为4 006.41 Hz，激发中心为2 250.59 Hz，H通道射频脉冲脉宽为10 μs，功率为21.8 W，弛豫延迟时间（D1）为2 s.累加次数为16，空采次数为16.脉冲序列中的扩散时间（Δ）为40 ms；梯度场脉冲宽度（δ）为1 800 μs，脉冲形状为梯形.每个DOSY实验中梯度场脉冲的强度（g）变化范围为5%~95%，采用线性方式在该范围中选取16个变化值.采样数据点为16 k，采样时间为2 s.1.3 数据处理所得的实验数据处理软件为Bruker公司提供的TopSpin 3.5pl7.通过其中的“DOSY”程序对实验得到的数据进行扩散系数拟合和反拉普拉斯变换，进而得到相应的DOSY图谱.处理过程中扩散系数维数据点为1 k，该维的取值范围（lgD）为-8 ~ -10，这两个处理参数其它的选值将在后面的讨论部分中加以具体说明.谱峰所对应的扩散系数值 D是由该峰的最高点在扩散系数维的投影值（lgD）读出并换算而得.2 结果与讨论2.1 DOSY实验偏差范围为了更准确地区分DOSY实验导致的偏差与数字分辨率引入的偏差，首先采用同样的样品与实验条件测试了6组DOSY实验以确定实验导致的偏差范围.每组实验连续测试5次，而1~6组实验依次之间的时间间隔为1天.图1为实验得到的DOSY图谱，其中以样品乙基苯中CH2峰（图中虚线所示位置）的数值代表乙基苯分子的扩散系数，共30个扩散系数值列于表1.表1 DOSY实验测得的乙基苯分子扩散系数Table 1 Self-diffusion coefficientsof ethylbenzene measured by DOSY experiments组别D/(×10-9 m2/s) 平均偏差d¯ 相对平均偏差d¯ r 1 1.611 1.618 1.611 1.611 1.625 0.0045 0.28%21.611 1.603 1.611 1.618 1.604 0.0047 0.29%3 1.596 1.604 1.618 1.611 1.5970.0074 0.46%4 1.582 1.575 1.575 1.582 1.582 0.0034 0.21%5 1.582 1.5751.582 1.582 1.589 0.0028 0.18%6 1.589 1.589 1.597 1.589 1.596 0.0036 0.23% 由于测试样品的溶剂为低粘度的氘代氯仿，有研究[23,24]表明这样的稀溶液在室温下只要存在控温的加热气流，就会产生沿NMR样品管方向的温度梯度，进而产生对流，影响扩散系数的测量.为避免此类现象对实验测量值造成偏差，上述所有实验都是在无温控和无温控气流的条件下进行的，实验室温度为（288±1）K.为了更好地呈现实验的偏差范围，采用了平均偏差（）及相对平均偏差（）的计算方法，其计算公式分别为：其中为扩散系数的平均值，n为计算所用的数据个数.表1中最后两列给出了每组5次连续实验的平均偏差（）及相对平均偏差（），其相对平均偏差都在0.5%以下.将6组30个数值一起计算时，平均偏差为0.012 6；相对平均偏差为0.79%.数值都略大于同组内5个数据的偏差值，可能的原因可归于实验期间实验室温度的起伏以及仪器上不可预测的不稳定性.总体而言，实验本身的相对平均偏差约为 1%.为进一步确认此偏差范围，对上述30个实验中的CH2谱峰面积进行了积分，将积分值及其相应的实验参数代入(1)式进行D值的拟合（拟合程序为BRUKER公司提供的“T1/T2 measure”程序），拟合出的平均偏差为0.014 7，相对平均偏差为0.92%.与DOSY图谱中得到的数值偏差基本一致，即在控制了诸多的影响因素之后，得到的实验本身的相对偏差在1%左右. 2.2 关于DOSY数据处理中扩散维数字分辨率的问题上述DOSY图谱的处理中在扩散系数维的取值范围（lgD）在-8 ~ -10之间，该取值范围是有机化合物在溶液中常见范围[25]，而该维所用的数据点是1 024，那么相邻两个数据点间lgD的差值为：[(- 8 )-(- 1 0)]/1024=0.00195，即数字分辨率（r）为0.001 95，对照表1可知其小于实验本身的平均偏差值，说明表1中DOSY实验数据偏差不完全是由数字分辨率的设置引入的.当扩散系数维是以对数形式（lgD）取值时，所有数据点间的间隔（即数字分辨率r）是相同的，而换算成 D值时，则数据点间隔是不等的.如图 2所示，x1数据点与相邻数据点间的间隔为（10 x 1 +r -10x1），而x2数据点与相邻数据点间的间隔则为（ 1 0 x 2 + r -10x2），x1和x2分别为相应数据点对应的 lgD.由此可见直接用 D值表示时，数据点间隔与数据点所在位置对应的扩散系数值相关，相互之间是不等的.但是当引入相对数字分辨率（R=数据点间隔/数据点对应的D 值），则上述间隔值转换为： (1 0 x 1 + r -10x1)/10 x 1 = 1 0r -1，与x1、x2无关.这表明对于一个处理参数（取值范围和数据点）已确定的DOSY图谱，其相对数字分辨率（ R = 1 0r -1）是一个恒定的值.正式发表的研究文献中通常都是直接用D值的变化大小，或以百分数表示其相对变化的大小，因此以相对数字分辨率R来表示其引入偏差的大小时更直观、更方便.根据上述所用的处理参数，图1中DOSY谱的数字分辨率r为0.001 95，相对数字分辨率R则为0.45%.为更明确地表明DOSY实验中数字分辨率的设置所引入的偏差，对表1中的第2组实验数据进行了不同数据点的处理，其结果列于表2.当取值范围（lgD）不变（-8 ~ -10），数据点为64和256时，它们所对应的相对数字分辨率R分别为7.46%和1.82%，表2中列出的5个数据之间只观察一个差值，其相对数据与相对数字分辨率基本一致，表明D值的偏差主要由数字分辨率不够高导致的.当数据点增加至1 024时，5个数据之间主要有2个差值（其中0.001的差值对于我们的研究没有意义，故舍去），其中一个的相对数据差值大于相对数字分辨率（约为2倍），说明此时的主要偏差不是来源于数字分辨率，因为数字分辨率引入的偏差只来源于相邻数据点的差别，不会大于相对数字分辨率本身.此外，由相对平均偏差的变化可知，随着数据点的增加，实验的精度也会逐渐提高.表2 不同数据点处理时扩散系数的偏差范围Table 2 Deviation range of self-diffusion coefficients when processing DOSY data with different data points*相对数据差=数据差值/数据点对应数值数据点D/(×10-9m2/s) 数据差值相对数据差* 相对数字分辨率相对平均偏差d¯r 64 1.778 1.655 1.778 1.778 1.778 0.123 7.43% 7.46% 3.94%256 1.625 1.625 1.625 1.655 1.655 0.030 1.85% 1.82% 1.44%1024 1.611 1.603 1.611 1.618 1.604 0.015 0.94% 0.45% 0.29%0.008 0.50%图3更直观地显示了数据点的多少对谱峰最高点（对应于扩散系数的读数）的影响，图中的谱峰来自于图1 DOSY图谱中虚线（通过CH2谱峰最高点）所在的化学位移位置（δ 2.67）对应的纵向一维谱.三角形、圆形和方形分别代表DOSY数据处理时所用数据点分别取128、512和1 024.从图中可以观察到当有足够多的数据点（如 1 024）时，这些数据点能较准确地描述出完整的峰型，包括谱峰的最高点；而数据点不足时不仅峰型描述得不够准确，更重要的是谱峰最高点的位置会随数据点移动，引起读数的偏差.图3 不同数据点处理时扩散系数维示意图Fig. 3 Sketch diagram of F1 dimension processed with different data points3 结论上述的研究结果表明DOSY图谱数据处理时如果设置的数据点不够多，导致数字分辨率不够高时，将会对实验所得的扩散系数测量值造成偏差，应当在设置相应的处理参数时予以充分考虑，并在成果发表时予以明确的陈述.当需要用扩散系数的变化值来表征分子结构或状态的变化时，相对数字分辨率应小于对应的相对变化值；当需要考虑扩散系数值的数据重复性时，建议相对数字分辨率R小于1%.从本文的研究结果中可知：扩散系数（lgD）取值范围为-8 ~ -10时，64、256和1 024个数据点对应的相对数字分辨率为7.46%、1.82%和0.45%.如果取值范围改变，则相对数字分辨率R= 1 0r -1（数字分辨率r=取值范围/数据点）也要做相应的调整.理论上如果相对数字分辨率为R，则由分辨率导致的读数偏差范围应该为（±R/2），由于数值范围上没有差别，为方便和容易理解，本文在所有的研究结果讨论中直接用R代替了±R/2.【相关文献】[1] JOHNSON C S. 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Self-compensating pulsed magnetic-field gradients for short recovery times[J]. J Magn Reson, 1994,108(2): 255-258.[8] BARJAT H, MORRIS G A, SMART S, et al. High-resolution diffusion-ordered 2D spectroscopy (HR-DOSY)-a new tool for the analysis of complex mixtures[J]. J Magn Reson, 1995, 108(2): 170-172.[9] Ca2+ assisted DOSY NMR: An unexpected tool for anomeric identification for D-glucopyranose[J]. ChemistrySelect, 2018, 3, DOI:10.1002/slct.201800316[10] TOUMI I, CALDARELLI S, TORRÉSANI B. A review of blind source s eparation in NMR spectroscopy[J]. Prog Nucl Magn Reson Spectrosc,2014, 81(8): 37-64.[11] PASTOR A, MARTÍNEZ-VIVIENTE E. NMR spectroscopy in coordination supramolecular chemistry: A unique and powerful methodology[J].Coordin Chem Rev, 2008, 252(21,22): 2314-2345.[12] MA E Q, LI Y X, ZHAO R G, et al. Interactions between NP-10 and single/double chain quaternary ammonium salts studied by NMR spectroscopy[J]. Chinese J Magn Reson, 2017, 34(1): 16-24.马二倩, 李永肖, 赵瑞格, 等. NP-10与单链、双链季铵盐三种复配体系相互作用规律的NMR研究[J]. 波谱学杂志, 2017, 34(1): 16-24.[13] KHODOV I A, ALPER G A, MAMARDASHVILI G M, et al. Hybrid multi-porphyrin supramolecular assemblies: Synthesis andstructure elucidation by 2D DOSY NMRstudies[J]. J Mol Struct, 2015, 1099: 174-180.[14] WANG L M, QIU R C, HUANG S H. Quantitative analysis of active ingredients in compound acetylsalicylic acid tablets by DOSY[J]. Chinese J Magn Reson, 2016, 33(3): 415-421.王丽敏, 仇汝臣, 黄少华. 复方乙酰水杨酸片中有效成分的DOSY技术分析[J]. 波谱学杂志, 2016, 33(3): 415-421.[15] TREFI S, GILARD V M M, MARTINO R. Generic ciprofloxacin tablets contain the stated amount of drug and different impurity profiles: A 19F,1H and DOSY NMR analysis[J]. J Pharmaceut Biomed Anal, 2007, 44(3): 743-754.[16] 崔艳芳, 刘买利. 应用DOSY-NMR分析血浆脂蛋白扩散系数的分布[C]. 南京: 第十一届全国波谱学学术会议, 2000.[17] ZHOU Q J, XIANG J F, TANG Y L. Applications of nuclear magnetic resonance spectroscopy in drug discovery[J]. Chinese J Magn Reson,2010, 27(1): 68-79.周秋菊, 向俊锋, 唐亚林. 核磁共振波谱在药物发现中的应用[J]. 波谱学杂志, 2010, 27(1): 68-79.[18] MONAKHOVA Y B, DIEHL B, DO T X, et al. Novel method for the determination of average molecular weight of natural polymers based on 2D DOSY NMR and chemometrics: Example of heparin[J]. J Pharm Biomed Anal, 2017, 149: 128-132.[19] BEDNAREK E, SITKOWSKI J, BOCIAN W, et al. An assessment of polydispersed species in unfractionated and low molecular weight heparins by diffusion ordered nuclear magnetic resonance spectroscopy method[J]. J Pharm Biomed Anal, 2010, 53(3): 302-308.[20] ANTALEK B. Using pulsed gradient spin echo NMR for chemical mixture analysis: How to obtain optimum results[J]. Concept Magn Reson A,2010, 14(4): 225-258.[21] ZHAO B, LI Y L, LI M, et al. An NMR study of capsaicin/β-cyclodextrin complex[J]. Chinese J Magn Reson, 2013, 30(4): 576-584.赵兵, 李艺蕾, 李明, 等. 辣椒碱与β-环糊精包合物的核磁共振研究[J]. 波谱学杂志, 2013, 30(4): 576-584.[22] CHEN X J, HU R Q, FENG H J, et al. Intradiffusion, density, and viscosity studies in binary liquid systems of acetylacetone + alkanols at 303.15 K[J]. J Chem Eng Data, 2012, 57(9): 2401-2408.[23] LOENING N M, KEELER J. Measurement of convection and temperature profiles in liquid samples[J]. J Magn Reson, 1999, 139(2): 334-341.[24] LAPPA M. Thermal convection: patterns, evolution and stability[M]. Wiley, 2009.[25] ANTALEK B. Using pulsed gradient spin echo NMR for chemical mixture analysis: How to obtain optimum results[J]. Concept Magn Reson A,2010, 14(4): 225-258.。

Matlab的第三方工具箱全套整合(强烈推荐)

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复变函数在信号与系统中的应用

复变函数在信号与系统中的应用1.复变函数在信号处理中被用来分析和处理信号的频谱特性。

Complex functions are used in signal processing toanalyze and process the frequency characteristics of signals.2.通过对复变函数的变换，可以将信号从时域转换到频域，方便进一步的分析和处理。

By transforming complex functions, signals can be converted from time domain to frequency domain, facilitating further analysis and processing.3.复变函数的共轭性质可以用来处理实函数信号的复数表达形式。

The conjugate properties of complex functions can be used to handle the complex representation of real-valued signals.4.应用拉普拉斯变换，可以将时域中的微分方程转换为频域中的代数方程。

By applying the Laplace transform, differential equations in the time domain can be transformed into algebraic equations in the frequency domain.5.在信号处理中，复变函数的奇偶性质可以帮助分析信号的对称性。

In signal processing, the odd and even properties of complex functions can help analyze the symmetry of signals.6.利用傅立叶变换，可以将信号分解为不同频率的正弦和余弦分量。

Editorial Reviews

Editorial ReviewsReviewEvery major topic is thoroughly covered, and every important concept is defined, described, and illustrated. Conceptually challenging but carefully explained articles will be equally valuable to practicing engineers, researchers and students.-Electronic Servicing & TechnologyThe entire work is heavy on math and includes excellent illustrations. In addition to the usual author and subject indexes, the reader will find indexes to the tables, figures, and equations, the latter being particularly useful. Because areas like communications and biomedical engineering are far from static, this new edition is a worthwhile addition as a technical reference.-John M. Robson…strongly recomm ended…This definitive handbook is a must for any ref erence library.M. S. Roden, California State University, Los AngelesProduct DescriptionIn 1993, the first edition of The Electrical Engineering Handbook set a new standard for breadth and depth of coverage in an engineering reference work. Now, this classic has been substantially revised and updated to include the latest information on all the im portant topics in electrical engineering today. Every electrical engineer should have an opportunity to expand his expertise with this definitive guide.In a single volume, this handbook provides a com plete reference to answer the questions encountered by practicing engineers in industry, government, or academia. This well-organized book is divided into 12 major sections that encompass the entire field of electrical engineering, including circuits, signal processing, electronics, electrom agnetics, electrical effects and devices, and energy, and the em erging trends in the fields of communications, digital devices, computer engineering, system s, and biomedical engineering. A com pendium of physical, chemical, m aterial, and mathematical data com pletes this com prehensive resource. Every major topic is thoroughly covered and every important concept is defined, described, and illustrated. Conceptually challenging but carefully explained articles are equally valuable to the practicing engineer, researchers, and students.A distinguished advisory board and contributors including m any of the leading authors, professors, and researchers in the field today assist noted author and professor Richard Dorf in offering com plete coverage of this rapidly expanding field. No other single volume available today offers this combination of broad coverage and depth of exploration of the topics. The Electrical Engineering Handbook will be an invaluable resource for electrical engineers for years to com e.About the AuthorDorf; Richard C. University of California, Davis, California, USA,Product Details∙ Hardcover: 2752 pages∙ Publisher: CRC; 2 edition (September 26, 1997) ∙ Language: English ∙ ISBN-10: 0849385741 ∙ ISBN-13: 978-0849385742∙ Product Dimensions: 10.3 x 8.7 x 3 inches ∙ Shipping Weight: 7.1 pounds ∙Average Customer Review:2 Reviews5 star :(1) 4 star :(1) 3 star : (0) 2 star : (0) 1 star :(0)› See all 2 customer reviews...∙ 4.5 out of 5 stars See all reviews (2 custom er reviews )∙ Sales Rank: #1,310,414 in Books (See Bestsellers in BooksContents:Circuits Introduction Passive Components ResistorsCapacitors and Inductors Transformers Electrical FusesVoltage and Current Sources Step, Impulse,Exponential and DC Signals Ideal and Practical Sources Controlled Sources Linear Circuit Analysis Voltage and Current Laws Node and Mesh Analysis Network TheoremsPower and Energy Three-Phase Circuits Graph TheoryThe Electrical Engineering Handbook 3rd Edition, 6 Volume Setby Richard C. Dorf, 3672 pp., ISBN: 084932274XThe Electrical Engineering Handbook, 3rd Edition -$209.95 eachEvery electrical engineer should have an opportunity to expand his expertise with this definitive guide.∙Provides the most comprehensive and authoritative reference available on all areas of electrical engineering∙Comes as a six-volume set packaged in an attractive, protective slipcase∙Comprises the latest work of foremost experts from all areas of electrical engineering∙ Presents each article with consistent quality, authority, and level of technical sophisticationTwo-Port Parameters and TransformationsPassive Signal Processing Nonlinear Circuits Diodes and Rectifiers Limiters DistortionLaplace Transform Definitions and Properties ApplicationsState Variables: Concept and Formulation The z-TransformT-XXX Equivalent Networks Transfer Functions of Filters Frequency Response Stability AnalysisComputer Softw are for Circuit Analysis and D esign Analog C ircuit Simulation Parameter Extraction for Analog Circuit Simulation Signal Processing Digital Signal Processing Fourier Tr ansformsFourier Tr ansforms and Fast Fourier Tr ansformDesign and Implementation of Digital Filters Signal R estoration Speech Signal Processing Coding, Transmission and StorageSpeech Enhancement and N oise ReductionAnalysis and Synthesis Speech Recognition Spectr al Estimation and Modeling Spectr al Analysis Parameter Estimation Multidimensional Signal ProcessingDigital Image Processing∙ Maintains consistency with IEEE reader∙Includes new discussions in areas such as nano-technology, fuel cells, embedded systems, and biometricsIn two editions spanning more than a decade, The Electrical Engineering Handbook stands as the definitive reference to the multidisciplinary field of electrical engineering.Our knowledge continues to grow, and so does the Handbook. For the third edition, it has grown into a set of six books carefully focused on specialized areas or fields of study.Each one represents a concise yet definitive collection of key concepts, models, and equations in its respective dom ain, thoughtfully gathered for convenient access.Combined, they consti tute the m ost com prehensive, authoritative resource available.The Electrical Engineering Handbook, 3rd Edition - $209.95 eachCircuits, Signals, and Speech and Im age Processing presents all of the basic information related to electric circuits and components, analysis of circuits, the use of the Laplace transform, as well as signal, speech, and image processing using filters and algorithms.It also examines em erging areas suc h as text to speech synthesis, real-tim e processing, and em bedded signal processing.Electronics, Power Electronics, Opto-electronics, Microwaves, Electro-m agnetics, and Radar delves into the fields of electronics, integrated circuits, power electronics, opto-electronics,electro-m agnetics, light waves, and radar, supplying all of the basic information required for a deep understanding of each area. It also devotes a section to electrical effects and devices and exploresVideo Signal Processing Sensor Array Processing VLSI for Signal Processing Special Architectures Signal Processing Chips and ApplicationsAcoustic Signal Processing Digital Signal Processing in Audio and Electro-acoustics Underwater Acoustical Signal ProcessingArtificial Neural Netw orks Computing Environments forDigital Signal Processing Electronics Introduction Semiconductors Physical Properties DiodesElectrical Equivalent C ircuit Models and D evice Simulators for Semiconductor Devices Semiconductor Manufacturing Processe sTesting Wayne N eedham Electrical Characterization of Interconnections TransistorsJunction Field-Effect Tr ansistors Bipolar TransistorsThe Metal-Oxide Semiconductor Field-Effect Transistor (MOSFET) Integrated C ircuits Integrated C ircuitTechnology Layout, Placement, and Routing Application-Specific Integrated C ircuits Surface Mount Technology Operational Amplifiers Ideal and Practical Models Applications AmplifiersLarge Signal Analysisthe em erging fields of m icro-lithography and power electronics.Sensors, Nano-science, Biomedical Engineering, and Instrum ents provides thorough coverage of sensors, materials and nano-science, instruments and m easurem ents, and biom edical system s and devices, including all of the basic information required to thoroughly understand each area.It explores the em erging fields of sensors, nano-technologies, and biological effects.Broadcasting and Optical Communication Technology explores communications, information theory, and devices, covering all of the basic information needed for a thorough understanding of these areas.The Electrical Engineering Handbook, 3rd Edition - $209.95 eachIt also examines the em erging areas of adaptive estim ation and optical communication.Computers, Software Engineering, and Digital Devices examines digital and logical devices, displays, testing, software, and com puters, presenting the fundamental concepts needed to ensure a thorough understanding of each field.It treats the em erging fields of programmable logic, hardware description languages, and parallel com puting in detail.System s, Controls, Embedded System s, Energy, and Machines explores in detail the fields of energy devices, m achines, and system s as well as control system s.It provides all of the fundamental concepts needed for thorough, in-depth understanding of each area and devotes special attention to the em erging area of em bedded systems.Encom passing the work of the world's foremost experts in their respective specialties, The Electrical Engineering Handbook, Third Edition remains the m ost convenient, reliable source of inform ation available.Small Signal Analysis Active FiltersSynthesis of Low-Pass Forms RealizationGeneralized Impedance Convertors and Simulated Impedances Power ElectronicsPower Semiconductor D evices Power Conversion Power SuppliesConverter C ontrol of Machines Optoelectronics LasersSources and Detectors CircuitsD/A and A/D Converters Thermal Management of ElectronicsDigital and Analog ElectronicDesign Automation Electromagnetics IntroductionElectromagnetic FieldsMagnetism and Magnetic Fields MagnetismMagnetic Recording Wave Propagation Space Propagation Waveguides Antennas Wire ApertureMicr ostrip Antennas Micr owave D evices Passive Microwave Devices Active Micr owave D evices CompatibilityGrounding, Shielding, and Filter ingSpectr um, Specifications, and Measurement Techniques Lightning RadarThe Electrical Engineering Handbook, 3rd Edition - $209.95 eachThis edition features the latest developm ents, the broadest scope of coverage, and new m aterial on nano-technologies, fuel cells, em bedded system s, and biometrics.The engineering community has relied on the Handbook for m ore than twelve years, and it will continue to be a platform to launch the next wave of advancem ents.The Handbook's latest incarnation features a protective slipcase, which helps you stay organized without overwhelming your bookshelf. It is an attractive addition to any collection, and will help keep each volume of the Handbook as fresh as your latest research.$209.95The Electrical Engineering Handbook, 3rd Edition - $209.95 eachPulse RadarContinuous Wave Radar Lightw aveLightw ave WaveguidesOptical Fibers and CablesSolid State CircuitsThree-Dimensional Analysis Computational Electr omagnetics Electrical Effects and Devices Electroacoustic D evices Surface Acoustic Wave Filters UltrasoundFerroelectric and Piezoelectric MaterialsElectrostrictionThe Hall Effect SuperconductivityPyroelectr ic Materials and DevicesDielectr ics and Insulators SensorsMagnetoopticsSmart Mater ialsEnergyConventional Power Generation Distributed Power Generation Transmission。

电热膜热成像英文文献

英文文献翻译The technology of generating infrared image basedon electric heating film technology基于电热膜技术的红外图像生成技术文献来源：脉冲功率激光技术国家重点实验室作者：路元，冯云松，乔涯译者：林凯鹏指导教师：胡长松The technology of generating infrared image based onelectric heating film technologyLu Yuan Feng Yun-song Qiao Ya(State Key Laboratory of Pulsed Power Laser Technology, Hefei Anhui 230037, China)ABSTRACTThe technology of generating infrared image based on electric heating film technology by its resistance per unit area was studied. A Lifgt-off-road vehicle was used as an object to be simulated. An infrared thermograph was used to photography the light-off-road vehicle from a specific corner. As a result several infrared images of the light-off-road vehicle were obtained and the thermal distribution of the vehicle was also obtained at the same time. A matlab program was used to process the image. The image was divided into several areas according to its grey level. Each area has its own temperature range. The average temperature of each area was calculated. A thermal balance equation was established according to the average temperature of each area and the environment temperature. By solving these equations, the radiant existances of these areas were gotten. The heating power per unit area of these areas was calculated. The electric heating film was preparation accordingly. The power was applied on the film and the infrared thermograph was used to observe it. The infrared image of the film has a high similarity with the true light-off-road vehicle ’s.Keywords: electric heating film, infrared image, simulation1. PRINCIPLES OF OPERATIONAll kinds objects have infrared radiation. The infrared radiant characteristic of an object is depending on its surface temperature and its surface emissivity. The radiation can be calculated by Planck equation. The usual form of the equation is written in terms of the radiant exitance as a function of wavelength. Considering the emissivity of a certain object, the radiant exitance can be written [1]:11251-=T c e c M λλλλε (1) Where λM is the spectral radiant exitance, 1c is the first radiation constant and 2c is the second radiationconstant. They are given by:-1-2821m Wm 10741832.32μπ⨯==hc cK m 10438786.1/22⋅⨯==-k hc c Where c is the speed of light in vacuum, h is Planck ’s constant, k is Boltzmann ’s constant, and T is the temperaturein kelvins. Since the emissivity is fixed for certain material, the temperature is the major factor that influences infrared radiation. It is usually more useful to know the value of the total power emitted from a body, rather than its spectral extent. The well-known Stephan-Boltzmann law gives the total radiant exitance as:4T M g εσ= (2)Where ε is the emissivity of an object. σ is the Stephan-Boltzmann constant. It has been evaluated and is given by]K Wm [1067.542-8-⨯=σFor an object, the reason of it showing different infrared image is that it has different temperature on different parts of it. Thus we can simulate a true object ’s infrared image by reappearing the temperature of the object.The technology of generating infrared image based on electric heating film technology was brought forward according to the infrared radiation theory. The main course is: the infrared image of an object was obtained firstly, and then the image was divided into several areas according to its temperature and its grey level. The radiation power of these parts was calculated. The resistance per unit area of these parts were calculated when the voltage of the film was certain. The heating film was prepared according to the resistance per unit area. When the film was heated by electricity power, the relevant infrared image will appear.2. INFRARED IMAGE OBTAIN OF AN OBJECT AND RELATIVELY CALCULATION2.1 infrared image and its temperature distributingA Light-off-road vehicle was used as an object to be simulated. The vehicle was fired up in idle state. Ten minutes late, an infrared thermograph was used to photography the light-off-road vehicle from a specific corner. Fig.1 was the infrared image of the vehicle.Fig.1 infrared image of a Light-off-road vehicleThe analysis and process to the image was carried out. The infrared image was divided into seven temperature areas by its grey level. These areas showed in fig.2. The average temperature of the area is the same for those areas which have the same number.Fig.2 the grey level of the vehicleThe average temperature of these areas showed in table 1 and the temperature of background is 24℃.Table 1 The average temperature of different areasFor these areas, we hypothesized that the area “i ” has a temperaturei T , the temperature background is B T . The acreage of area “i ” isi A . The acreage of these areas is calculated.2.2 Heating power calculationWhen the electric heating film was powered on, most of the electron power it gotten was converted to heat power. The temperature of these areas rose. The temperature of these area achieve maximum when the area was in thermal equilibrium state with the environment. When the film was in thermal equilibrium, we have: i i Q =Φ (3)Where i Q is the heating power of area “i ” and i Φ is the lost power of the area “i ” because of the heat exchange between the area and the environment.The heat exchanges [3] between the area “i ” and the environment were composed of two parts: radiation heat transfer and convective heat transfer. The lost power of area “i ” is the sum of radiation heat transfer and convective heat transfer:44()()B B B i i i i i A T T hA T T σεεΦ=-+- (4)Where ε is surface emissivity of the film andB ε is the emissivity of background, h is heat transfer coefficient ofthe surface.When it was in heat balance, we have44()()B B B i i i i i P A T T hA T T σεε=-+- (5)Wherei P is the heating power of area “i ” of the film.2.3 Methods of temperature controlling and relative calculationThere are three methods for the film to control the temperature. The first method is that all areas were connected in series and one power was used to supply power. The second method is that all areas were connected in parallel and one power was used to supply power. The third method is that every area was supplied by different power. The voltage of the power can be 220V, 110V, 24V and 12V. Both ac power and dc power can be used. The first method was used. Thus we have: 2i i P I R = (6)1n i i PUI ==∑ (7)Where I is the current in the film, i R is the resistance of area “i ” and U is voltage added on the whole film.3. SIMULATION OF THE INFRARED OBJECTThe acreage of these areas was calculated by AUTOCAD software. For convenience, we scale down the size of the film. Assuming the length of film is 0.5m, the acreages of these areas are calculated and which was showed in table 2.Table 2 The acreage of these areas on filmThe heat power of these areas was calculated and showed in table 3.Table 3 The heat power of these areas on filmThe power per unit area was calculated and showed in table 4.Table 4 The power per unit area of these areas on filmAssuming the power was 20V in dc. The resistance of these areas was showed in table 5.Table 5 The resistance of these areas on filmAccording to the data, the film was prepared . A couple conductors were extracted from the film. When the power was applied on the film, the infrared image will appear of a Light-off-road vehicle will appear.4. INFRARED IMAGE GENERATION AND EVALUATION4.1 infrared image generation of the filmA rectangle on electric heating film was made according the data calculated [5]. When the power was on, an infrared thermograph was used to observe the film. The images we gotten by an infrared thermograph were showed in fig. 3. These images were the infrared images of the film when the film was powered on. These images were captured when the time was at 0 and 4th, 10th, 16th, 22nd, 28th, second.On these images, we can see that the infrared image of the film was appeared as a Light-off-road vehicle when the power was on. It was vague at first, and then it became clearer when the time went on.Fig. 3 infrared images generated by the heating film4.2 evaluation of infrared image of the filmThe infrared images were evaluated according to reference 6; the similarity defined in reference 6 was used. The infrared image of true vehicle and the infrared image of the film were extracted. The pixels were 296×140. The infrared image of the vehicle was showed in fig.5 and the infrared images of the film were showed in fig.6. The infrared image of the film was captured at 0 second and 4th, 10th, 16th, 22nd, 28th, second.Fig.4 infrared image of the vehicleFig5. Infrared images of the heating filmThe similarity [6] between the infrared image of the true vehicle and the infrared image of the film was calculated according to reference [6]. The result was showed in table 6.Table 6 The image similarity between the vehicle and the heating filmFrom the table 6, we can see that the similarity between infrared image of the film and it of the vehicle was different for the time we capturing images. The similarity became bigger when the infrared image of the became clearer. When the time was 28th second, the similarity achieved 0.7724. For the reason that technology level of making film, data ’s accepted or rejected, there will be error on property of the film between the film we made and the film we designed. These will reduce the similarity on infrared images between the film and the true vehicle.5. CONCLUSIONThe technology can be used to simulate infrared image of a true object. By improving the technology, the simulation effect will be promoted. The method can be applied to many fields such as infrared decoy target, infrared thermography simulation and infrared equipment inspection.Reference ：1. M. Planck, Theory of Heat, Macmillan, New York(1957)2. M. A. Bramson, Infrared, A Handbook for Application, Plenum Press, New York(1966).3. Yuan LU ，Dan WU ，Wei JIN ， De-peng HOU, A Study on Infrared Radiation of Terrain by Modeling, Infrared Technology, Vol.30 No.2, 75-79, (2008).4.Hong-ye CHEN, Zhao-yang ZENG, Wen-bin XIE, Jun-yu LU, ZHU Chao,Thermal Characteristic Analysis for Electric Heating Film as Infrared Decoy, LASER & INFRARED, Vo.l 37, No. 4, 336-337, (2007)5. ZENG Zhao-yang,CHENHong-ye,CHEN Kui-feng, The Characteristic of Electric Heating Film and Its Application in Military, LASER & INFRARED, Vo.l 38, No. 9 894-896, (2008).6. Weidong Xu, xuliang lu, A model based on texture analysis for the performance evaluation of camouflage screen equipment. ACTA ARMAMENTARII, Vol. 23 No.3 329-331(2002).摘要基于电热膜技术以其单位面积电阻产生的红外图像进行了工艺研究.一种轻型越野车为对象进行模拟。

中红外光谱模型用于烤肉中苯并[a]芘的快速检测和评估

基金项目：烹饪科学四川省高等学校重点实验室开放基金项目（编号：ＰＲＫＸ２０１７Ｚ０５）作者简介：邵淑娟，女，菏泽市行政审批服务局、菏泽市食品药品检验检测研究院高级工程师，硕士。

通信作者：李丽（１９８２—），女，四川轻化工大学副教授，博士。

Ｅｍａｉｌ：ｋｏｋｏｎｉｃｅ＠１３９．ｃｏｍ收稿日期：２０２２０８０９改回日期：２０２３０１１０犇犗犐：１０．１３６５２／犼．狊狆犼狓．１００３．５７８８．２０２２．８０６５７［文章编号］１００３５７８８（２０２３）０３００３４０４中红外光谱模型用于烤肉中苯并［ａ］芘的快速检测和评估Ｒａｐｉｄｄｅｔｅｃｔｉｏｎａｎｄｅｖａｌｕａｔｉｏｎｏｆｂｅｎｚｏ［ａ］ｐｙｒｅｎｅｉｎｂａｒｂｅｃｕｅｂｙｍｉｄｉｎｆｒａｒｅｄｓｐｅｃｔｒｏｓｃｏｐｙｍｏｄｅｌ邵淑娟１，２犛犎犃犗犛犺狌犼狌犪狀１，２　李　丽３犔犐犔犻３　温　磊３犠犈犖犔犲犻３　宋　欢４犛犗犖犌犎狌犪狀４　阳生琼５犢犃犖犌犛犺犲狀犵狇犻狅狀犵５（１．菏泽市行政审批服务局，山东菏泽　２７４０００；２．菏泽市食品药品检验检测研究院，山东菏泽　２７４０００；３．四川轻化工大学生物工程学院，四川宜宾　６４４０００；４．四川戎测质检技术服务有限公司，四川宜宾　６４４０００；５．宜宾中山医院，四川宜宾　６４４０００）（１．犎犲狕犲犃犱犿犻狀犻狊狋狉犪狋犻狏犲犈狓犪犿犻狀犪狋犻狅狀犪狀犱犃狆狆狉狅狏犪犾犛犲狉狏犻犮犲犅狌狉犲犪狌，犎犲狕犲，犛犺犪狀犱狅狀犵２７４０００，犆犺犻狀犪；２．犎犲狕犲犐狀狊狋犻狋狌狋犲狅犳犉狅狅犱犪狀犱犇狉狌犵犐狀狊狆犲犮狋犻狅狀犪狀犱犜犲狊狋犻狀犵，犎犲狕犲，犛犺犪狀犱狅狀犵２７４０００，犆犺犻狀犪；３．犆狅犾犾犲犵犲狅犳犅犻狅犲狀犵犻狀犲犲狉犻狀犵，犛犻犮犺狌犪狀犝狀犻狏犲狉狊犻狋狔狅犳犛犮犻犲狀犮犲犪狀犱犈狀犵犻狀犲犲狉犻狀犵，犢犻犫犻狀，犛犻犮犺狌犪狀６４４０００，犆犺犻狀犪；４．犛犻犮犺狌犪狀犚狅狀犵犮犲犙狌犪犾犻狋狔犐狀狊狆犲犮狋犻狅狀犜犲犮犺狀狅犾狅犵狔犛犲狉狏犻犮犲犆狅．，犔狋犱．，犢犻犫犻狀，犛犻犮犺狌犪狀６４４０００，犆犺犻狀犪；５．犢犻犫犻狀犣犺狅狀犵狊犺犪狀犎狅狊狆犻狋犪犾，犢犻犫犻狀，犛犻犮犺狌犪狀６４４０００，犆犺犻狀犪）摘要：目的：实现烤肉制品中苯并［ａ］芘含量的快速检测。

菲利普·音频 Diamond Compressor 说明书

Thanks for purchasing a Diamond Compressor! We hope you have as much fun playing guitar through this pedal as we did designing and testing it. Our goal is to provide a versatile ‘guitar channel’ – a dynamics and tone shaping tool to front-end your effects chain.Remember to protect your hearing and wear appropriate hearing protection when playing loud…Design FeaturesVactrol opto-isolator variable resistance path as used in high-end studio compressors for smooth attack and decay characteristics while preserving initial signal transients.Post-compressor ‘tilt’ EQ provides a very musical tailoring of frequency response - seamlessly transition from a darker jazz voicing to a bright jangle, with ﬂat frequency response at the cen-ter detent position.Optimized gain staging and use of ultra low noise transistor and opamps in signal path for lowest possible noise and extended signal headroom.Premium audio components, including 2% polypropylene capacitors and 1% metal ﬁlm resistors.Dual AC capacitive coupling paths for improved transient response.Bi-color LED provides visual indication of depth of compression.True bypass signal path.Battery or standard negative tip 9V DC adapter operation, can be powered from 9 to 24 V nega-tive tip.C O M P R E S S O R��ControlsCompThis controls the amount of compression to be applied to the guitar signal. Backing it off all the way gives just a touch of compression on signal peaks, while turning the control clockwise gives an increasing amount of signal ‘squash’. The compression threshold, the input signal level at which compression begins to take effect, is sensitive to level variations like pickup output and4.8 kHz cutoff, 6 dB/octave lowpass ﬁlter between the tilt EQ and volume control. This will help reduce any audible ampliﬁcation of low level white noise by subsequent high gain stages with-out signiﬁcant impact on the midrange band. The jumper is easy to set – with the pedal oriented with the effect on-off switch at the bottom, ﬁrst ﬁnd the jumper located to the left of the EQ slider switch, then move the jumper from the bottom and middle pins (hi-cut ﬁlter out) to theC O M P R E S S O RUsage NotesHow The Compressor WorksThe basic concept behind compression is simple: the audio level in the signal path is measured and this value is then used to control the overall output level by some amount proportionate to the measured level. There have been a number of different schemes and circuit topologies de-signed over the years to accomplish this task – it’s well beyond the scope of this user manual to delve into all of them in detail. The Diamond Compressor uses a simple and relatively non-intru-sive resistive divider gain reduction system that utilizes an analog optical isolator to map output signal level to a variable resistance. The opto-isolator (for short) is placed in a feedback loop – it uses the output level from the gain reduction system to stabilize its own gain reduction system. This stabilization can seem somewhat counterintuitive, but basically the louder the signal, the more gain reduction takes place, which lowers the signal level, and reduces the gain reduction, and so on… until the output level stabilizes at some reduced level. The amount of reduction that takes place is dependent on the input signal level, the amount that level is above a gain-reduc-tion threshold , and the steepness of the gain reduction slope once the threshold is met. Basi-cally, any input signal below the threshold is not compressed, and any signal rising above the threshold is reduced in level by a gain-reduction slope or ratio . The Diamond Compressor has a very simple system for providing control over compression. The Comp control is in reality a con-trol for a voltage ampliﬁer placed in the signal path which performs several duties:it provides make-up gain to compensate for overall loudness loss due to the resistivedivider compression loss circuitit provides a mechanism to boost the input signal which in turn has the effect of increas-ing the amount of signal above the ﬁxed threshold in the signal level measuring circuit (aka sidechain ). The more signal above the threshold, the deeper the attenuation of the resistive divider , and the more perceived ‘compression’.The Volume control is simply a ﬁnal attenuator that the user can use to balance the perceived loudness between effect on and off. This volume balance between effect on and off is very much dependent on how hard the player picks – try setting the Volume and Comp controls iteratively to the desired amount of compression and overall level while playing a chord or run at your usual picking strength.Unfortunately, there’s still a bit more to it all… Along with the threshold and compression ra-tio, the ‘personality’ of a compressor is deﬁned by just how quickly (or not quickly) it reacts to changes in level. Things can get really confusing here… Each guitar note played has certain dynamic characteristics. Sound synthesis people often talk about ADSR – Attack, Decay, Sustain and Release when designing synthesizer sounds or patches, and many of those concepts hold for how a compressor reacts to a guitar waveform. Basically, when a note is picked, there is a short Attack and Decay period that covers the initial transient of the picking action. The string then begins to vibrate in a more steady-state fashion for a certain period of time, constantly decay-a.b.Diamond Pedals carry a full ﬁve year warranty on registered products - make sure to send us your warranty card! The warranty is simple - if you have a problem, call us, send us the pedal if necessary, and we’ll make it right.ing until either stopped, picked again, or let die out. For simplicity, we’ll call this the Sustain of the note, we won’t worry about the mechanics of the Release action. When a note is picked, it takes a ﬁnite amount of time for the compressor to measure the rising signal and then begin to attenuate it once it exceeds the compressor’s threshold. If the speed of the compressor is too fast, too much of the initial note transient may get attenuated giving a ‘lifeless’ kind of sound. Conversely, beginning compression too long after the initial transient has begun can lead to an uneven and unnatural note dynamic. On the release side, having a compressor that removes itsBasic Comp��Really nice for smoothing out piezo pickups.��。

spectrum

AbstractÐA menu-driven PC program (SPECTRUM) is presented that allows the analysis of unevenly spaced time series in the frequency domain. Hence, paleoclimatic data sets, which are usually irregularly spaced in time, can be processed directly. The program is based on the Lomb±Scargle Fourier transform for unevenly spaced data in combination with the Welch-Overlapped-Segment-Averaging procedure. SPECTRUM can perform: (1) harmonic analysis (detection of periodic signal components), (2) spectral analysis of single time series, and (3) cross-spectral analysis (cross-amplitude-, coherency-, and phase-spectrum). Cross-spectral analysis does not require a common time axis of the two processed time series. (4) Analytical results are supplemented by statistical parameters that allow the evaluation of the results. During the analysis, the user is guided by a variety of messages. (5) Results are displayed graphically and can be saved as plain ASCII ®les. (6) Additional tools for visualizing time series data and sampling intervals, integrating spectra and measuring phase angles facilitate the analysis. Compared to the widely used Blackman±Tukey approach for spectral analysis of paleoclimatic data, the advantage of SPECTRUM is the avoidance of any interpolation of the time series. Generated time series are used to demonstrate that interpolation leads to an underestimation of high-frequency components, independent of the interpolation technique. # 1998 Elsevier Science Ltd. All rights reserved Key Words: Spectral analysis, Harmonic analysis, Cross-spectral analysis, Irregular sampling intervals, Interpolation, Lomb±Scargle Fourier transform.

Spectral LAB 软件介绍

Spectral LAB 软件介绍1.前言1.1 欢迎使用本软件Spectral LAB是一个功能强大的双通道频谱分析仪，装有任何与Windows兼容的声卡，就可以进行实时频谱分析、数据记录、回放及后处理。

可用来测量频率响应、失真及传递函数，支持多达65535点的FFT、加窗、数字滤波、重叠处理、平均、峰值保持、触发、抽取窄带和倍频程分析（1/1,1/3,1/6,1/9,1/12），能够显示、导出、和打印时间序列、频谱（spectrum）、相位、3－D轮廓图（3－D surface plot）及谱图（Spectrogram），其中信号发生器工具可以产生粉红／白噪声、扫频正弦、音频和脉冲信号，采用高速CPU，可以进行实时操作。

1.2 什么是频谱分析仪是一台把信号从时域（幅度—时间）转换到频域（幅度—频率）的仪器。

音频频率分析仪（Audio Spectrum Analyzer）就是处理音频范围内的信号，计算机上所装的声卡的频率范围限制了软件的分析频率。

程序工作与所装的声卡有关，将待测音频信号接入声卡后面的Line-in或Mic插座，然后程序使用声卡实现A/D转换，数字化了的音频信号通过FFT算法，被转换到了频域。

1.3系统配置2．测量2.1 基本操作程序由3种完全不同的工作方式及5种独立的界面。

实时方式—直接处理来自声卡的信号并显示结果，不保存原始数据所以无法存盘，但可无限运行下去；记录器方式—将数字化了的信号（数据）以*.wav的文件格式存入硬盘，可以通过连在声卡上的扬声器进行回放。

后处理方式—处理以前存在硬盘上的*.wav格式的音频数据，分析时该方式比前两种方式有更大的灵活性，允许使用重叠处理，这样在3－D和谱图中可有效的延长时间分辨率。

5种界面（窗口）：时间序列窗口—显示数字化的声音信号波形，类似示波器现实；频谱窗口—显示信号幅度与频率的关系；相位窗口—显示信号相位与频率的关系；谱图窗口—显示频谱随—时间图，幅度用彩色或灰度表示；3－D窗口—显示频谱与时间的立体图。

PbSe量子点近红外光源的CH 4 气体检测

第４期
邢笑雪，等：ＰｂＳｅ量子点近红外光源的ＣＨ４气体检测
６６３
ｄｏｔｓｎｅａｒｉｎｆｒａｒｅｄｌｉｇｈｔｓｏｕｒｃｅｈａｓｔｈｅａｄｖａｎｔａｇｅｓｏｆｌｏｗｐｏｗｅｒｃｏｎｓｕｍｐｔｉｏｎ，ｌｏｗｃｏｓｔａｎｄｈｉｇｈｅｆｆｉｃｉｅｎｃｙ．Ｗｈｅｎｉｔｉｓｕｓｅｄｉｎｇａｓｄｅｔｅｃｔｉｏｎ，ｔｈｅｆｉｌｔｅｒｃａｎｂｅｏｍｉｔｔｅｄ，ａｎｄｉｔｈａｓａｂｒｏａｄａｐｐｌｉｃａｔｉｏｎｐｒｏｓｐｅｃｔｉｎｔｈｅｆｉｅｌｄｏｆｉｎｆｒａｒｅｄｇａｓｄｅｔｅｃｔｉｏｎ．Ｋｅｙｗｏｒｄｓ：ＣＨ４ｇａｓｄｅｔｅｃｔｉｏｎ；ＰｂＳｅｑｕａｎｔｕｍｄｏｔｓ；ｎｅａｒｉｎｆｒａｒｅｄｌｕｍｉｎｅｓｃｅｎｃｅ
的发光谱和ＣＨ４的吸收谱线的对比图。从图２中可以看出，ＣＨ４气体在１６２５～１８４０ｎｍ范围内吸收谱线特征明显，其在１６５３ｎｍ处有一个强吸收峰，５１ｎｍ的ＰｂＳｅ量子点近红外光源的发光峰位于１６６５ｎｍ处（半峰宽度为１４０ｎｍ），其发光谱完全覆盖了ＣＨ４气体的吸收谱。
图３５．１ｎｍＰｂＳｅ量子点吸收谱线Ｆｉｇ．３Ｎｏｒｍａｌｉｚｅｄａｂｓｏｒｐｔｉｏｎｓｐｅｃｔｒｕｍｏｆ５．１ｎｍＰｂＳｅ
１引言
近年来，量子点半导体材料成为了科学研究的热点之一，它被广泛应用于光电探测器、电致发光器件、太阳能电池、生物成像等多种领域。［１８］量子点光致发光波段具有随量子点尺寸改变而迁移的特性，使得量子点在光转换领域中具有较好的应用前景。［９１２］ＰｂＳｅ体材料在室温下具有窄的带隙，仅为０２８ｅＶ，它的激子玻尔半径为４６ｎｍ。因此，ＰｂＳｅ量子点在近红外波段具有较强的量子限制效应和较高的量子产率。此外，ＰｂＳｅ在红外波段的边带光致发光峰跨度较大，为１～４μｍ。