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  • [期刊] CuO/Cu_2O nanowire array photoelectrochemical biosensor for ultrasensitive detection of tyrosinase
    摘要:Photoelectrochemical(PEC) biosensors have shown great promise in bioanalysis and diagnostic applications in recent years. In this work, the CuO/Cu_2O nanowire array(CuO/Cu_2O Nanowire) supported on copper foam was prepared as a photocathode for detection of tyrosinase though quinone-chitosan conjugation chemistry method. The in-situ generated quinones that were the catalytic product of tyrosinase acted as electron acceptors, which were captured by the chitosan deposited on the surface of the electrode. Direct immobilization of electron acceptor on the electrode surface improved the photocurrent conversion efficiency and thus sensitivity. The as-prepared biosensor can realize a rapid response in a wide linear range of 0.05 U/mL to 10 U/mL with the detection limit as low as 0.016 U/mL of tyrosinase. The current work provides a new perspective to design and develop highly sensitive and selective PEC biosensor.
  • [期刊] A review of enantioselective dual transition metal/photoredox catalysis
    摘要:Transition metal catalysis is one of the most important tools to construct carbon-carbon and carbon-heteroatom bonds in modern organic synthesis. Visible-light photoredox catalysis has recently drawn considerable attention of the scientific community owing to its unique activation modes and significance for the green synthesis. The merger of photoredox catalysis with transition metal catalysts, termed metallaphotoredox catalysis, has become a popular strategy for expanding the synthetic utility of visiblelight photocatalysis. This strategy has led to the discovery of novel asymmetric transformations, which are unfeasible or not easily accessible by a single catalytic system. This contemporary area of organic chemistry holds promise for the development of economical and environmentally friendly methods for the asymmetric synthesis of chiral compounds. In this review, the advances in the enantioselective metallaphotoredox catalysis(EMPC) are summarized.
  • [期刊] A review of enantioselective dual transition metal/photoredox catalysis
    摘要:Transition metal catalysis is one of the most important tools to construct carbon-carbon and carbon-heteroatom bonds in modern organic synthesis. Visible-light photoredox catalysis has recently drawn considerable attention of the scientific community owing to its unique activation modes and significance for the green synthesis. The merger of photoredox catalysis with transition metal catalysts, termed metallaphotoredox catalysis, has become a popular strategy for expanding the synthetic utility of visiblelight photocatalysis. This strategy has led to the discovery of novel asymmetric transformations, which are unfeasible or not easily accessible by a single catalytic system. This contemporary area of organic chemistry holds promise for the development of economical and environmentally friendly methods for the asymmetric synthesis of chiral compounds. In this review, the advances in the enantioselective metallaphotoredox catalysis(EMPC) are summarized.
  • [期刊] CuO/Cu_2O nanowire array photoelectrochemical biosensor for ultrasensitive detection of tyrosinase
    摘要:Photoelectrochemical(PEC) biosensors have shown great promise in bioanalysis and diagnostic applications in recent years. In this work, the CuO/Cu_2O nanowire array(CuO/Cu_2O Nanowire) supported on copper foam was prepared as a photocathode for detection of tyrosinase though quinone-chitosan conjugation chemistry method. The in-situ generated quinones that were the catalytic product of tyrosinase acted as electron acceptors, which were captured by the chitosan deposited on the surface of the electrode. Direct immobilization of electron acceptor on the electrode surface improved the photocurrent conversion efficiency and thus sensitivity. The as-prepared biosensor can realize a rapid response in a wide linear range of 0.05 U/mL to 10 U/mL with the detection limit as low as 0.016 U/mL of tyrosinase. The current work provides a new perspective to design and develop highly sensitive and selective PEC biosensor.
  • [期刊] 抑制型离子色谱法电导检测畜禽肉中硝酸盐和亚硝酸盐
    摘要:本试验在优化前处理方法和仪器检测条件的基础上,建立了一种可同时检测畜禽肉及其制品中硝酸盐和亚硝酸盐含量的抑制型离子色谱法。样品均质后,经超声萃取、静置分离,加入二氯甲烷除去蛋白质、脂肪等物质。取上清液过滤净化,以氢氧化钾为淋洗液,采用抑制型离子色谱法电导检测器检测。硝酸盐与亚硝酸盐的分离度良好,定量限分别为0.3、0.2 mg·kg~(-1),检出限分别为0.09、0.06 mg·kg~(-1),并分别在0.2 ~ 2.0 mg·kg~(-1)、0.02 ~ 0.2 mg·kg~(-1)浓度内,呈良好线性关系。在低、中、高3个浓度水平加标并平行测定6次,猪、牛、羊、鸡和鸭中硝酸盐和亚硝酸盐的加标回收率平均值分别在77.0% ~ 106.1%、77.3% ~ 101.0%、65% ~ 97.5%、80.0% ~ 103.3%、90.5% ~ 99.2%,平均相对标准偏差(relative standard deviation, RSD)均小于8.75%。本试验建立的方法简便快捷,检测结果准确可靠、回收率高、精密度良好,可以满足畜禽肉及其制品中硝酸盐与亚硝酸盐的同时检测。
  • [期刊] 核酸适配体亲和柱净化富集莲子中黄曲霉毒素B_(1)及其测定
    摘要:以高亲和力、特异性强的核酸适配体作为新型识别元件,制备了黄曲霉毒素B_(1)的适配体亲和柱,并用于黄曲霉素素B_(1)的特异性识别和富集。通过对适配体亲和柱的载样液中有机溶剂含量、载样液的体积和淋洗体积等条件进行优化,该适配体亲和柱的柱容量达到(329.2 ± 12.5) ng。莲子样品经适配体亲和柱净化富集后,用高效液相色谱-光化学衍生荧光法检测,外标法定量,检出限达到0.05 ng/mL,回收率为91.8%~108.6%。此适配体亲和柱最少可重复使用20次。本方法为食品、农产品和中药等复杂基质中痕量毒素的提取富集和分析提供了新的选择,具有良好的应用前景。
  • [期刊] 乳腺癌生物标志物钙网蛋白的核酸适配体筛选及血清检测和乳腺癌细胞识别
    摘要:钙网蛋白(CRT)与许多癌症的发生密切相关,并被认为是有效的新型乳腺癌侵袭和转移的生物标志物以及乳腺癌分期和预后的评价指标。本研究利用毛细管电泳-指数富集配体进化技术(CE-SELEX)筛选并鉴定了CRT的核酸适配体。通过毛细管电泳法,等温滴定量热法及纳米金比色法表征了所筛选的适配体Apt 23具有较高的亲和力和特异性。FAM标记的Apt 23(FAM-Apt23)可用作毛细管电泳的亲和探针,在激光诱导荧光检测下,可检出血清中1~1000 nmol/L的CRT,检出限为0.5 nmol/L。FAM-Apt 23也可用作CRT的免疫荧光成像探针,可结合在CRT过表达的乳腺癌细胞4T1的表面。初步研究表明,利用毛细管电泳筛选的核酸适配体Apt 23可用于CRT识别和检测的探针。
  • [期刊] 碱性阴离子交换膜燃料电池实验及数值模拟
    摘要:针对碱性阴离子交换膜燃料电池(AEMFC)水管理开展了实验及数值模拟工作,使用TokuyamaA201膜制备并组装了实验室规模的AEMFC单电池,建立了一个基于质量守恒、组分守恒、电荷守恒的碱性阴离子交换膜燃料电池二维稳态等温模型,用于研究电池性能及内部水传输机理。通过模型计算分析电池性能及内部水传输和水分布情况,结果表明:计算预测得到的特定参数下的极化曲线趋势与单电池测试的数据吻合良好;电流密度增加会增大水从阳极到阴极的净通量,有利于阴极反应的进行;电池两极均需进气加湿,提高阳极进气湿度可以加快水从阳极到阴极的净迁移,在较高电流密度下阴极进气湿度过低对电池性能影响较大。
  • [期刊] 二(4-苄氧苯基)二硒醚的设计与制备:一种铜残留清除剂(英文)
    摘要:通过往分子中引入苄氧取代基所制备出的二(4-苄氧苯基)二硒醚,与普通富电子或缺电子二硒醚相比,更能够清除铜污染物。在室温下,该化合物4小时内即可完全清除二价铜离子.该物质可被应用到伊马替尼全合成中,以降低产品中的催化剂铜残留.通过加入仅仅1 mol%的二(4-苄氧苯基)二硒醚,可将伊马替尼碱产品中的铜残留抑制到0.1ppm.上述结果表明该有机硒化合物在制药工业有着很好的应用潜力.本工作报导了一种新颖的利用硒与铜配位作用清除铜残留的方法。由于硒元素安全、可降解,该方法有望被应用于制药工业.
  • [期刊] 基于随机森林算法的大功率质子交换膜燃料电池系统故障分类方法
    摘要:针对大功率质子交换膜燃料电池(proton exchange membrane fuel cell,PEMFC)系统故障分类识别的问题,提出基于随机森林算法(random forest, RF)的燃料电池系统的故障分类方法。该方法基于Bootstrap法重采样,产生多个样本子集,通过决策树算法中的CART算法构造多个分类器模型,然后通过测试集对每个分类器进行测试得到分类结果,最后投票选出最优的分类结果作为预测类别。通过实例分析,对比支持向量机(support vector machine, SVM)和K最邻近(k-nearest neighbor, KNN)算法的分类结果,本文所提方法可有效识别有轨电车实际运行过程中5种故障状态,分类准确率可达94.4%,能明显提高故障分类正确率,对进一步实现大功率PEMFC系统在线故障诊断研究具有重要意义。

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