Four rice samples of long grain type were tested using an electronic nose (Cyranose-320).Samples of 5 g of each variety of rice were placed individually in vials and were analyzed with the electronic nose unit consist...Four rice samples of long grain type were tested using an electronic nose (Cyranose-320).Samples of 5 g of each variety of rice were placed individually in vials and were analyzed with the electronic nose unit consisting of 32 polymer sensors.The Cyranose-320 was able to differentiate between varieties of rice.The chemical composition of the rice odors for differentiating rice samples needs to be investigated.The optimum parameter settings should be considered during the Cyranose-320 training process especially for multiple samples,which are helpful for obtaining an accurate training model to improve identification capability.Further,it is necessary to investigate the E-nose sensor selection for obtaining better classification accuracy.A re- duced number of sensors could potentially shorten the data processing time,and could be used to establish an application pro- cedure and reduce the cost for a specific electronic nose.Further research is needed for developing analytical procedures that adapt the Cyranose-320 as a tool for testing rice quality.展开更多
An electronic-nose is developed based on eight quartz-crystal-microbalance (QCM) gas sensors in a sensor box, and is used to detect Chinese liquors at room temperature. Each sensor is a highly-accurate and highly-sens...An electronic-nose is developed based on eight quartz-crystal-microbalance (QCM) gas sensors in a sensor box, and is used to detect Chinese liquors at room temperature. Each sensor is a highly-accurate and highly-sensitive oscillator that has experienced airflow disturbances under the condition of varying room temperatures due to unstable flow-induced forces on the sensors surfaces. The three-dimensional (3D) nature of the airflow inside the sensor box and the interactions of the airflow on the sensors surfaces at different temperatures are studied by computational fluid dynamics (CFD) tools. Higher simulation accuracy is achieved by optimizing meshes, meshing the computational domain using a fine unstructural tetrahedron mesh. An optimum temperature, 30 ℃, is obtained by analyzing the distributions of velocity streamlines and the static pressure, as well as the flow-induced forces over time, all of which may be used to improve the identification accuracy of the electronic-nose for achieving stable and repeatable signals by removing the influence of temperature.展开更多
以辐照0、1、3、5 k Gy的黄山毛峰和祁门红茶为研究对象,通过优化电子鼻测茶叶香气的技术参数,并对未辐照和辐照茶叶、辐照茶叶不同辐照剂量组的气味数据进行主成分分析(PCA)和线性判别函数分析(LDA),研究电子鼻技术在茶叶辐照鉴定中的...以辐照0、1、3、5 k Gy的黄山毛峰和祁门红茶为研究对象,通过优化电子鼻测茶叶香气的技术参数,并对未辐照和辐照茶叶、辐照茶叶不同辐照剂量组的气味数据进行主成分分析(PCA)和线性判别函数分析(LDA),研究电子鼻技术在茶叶辐照鉴定中的应用效果。结果表明,利用电子鼻技术可显著区分辐照茶叶和未辐照茶叶,区分率为1.000,并且在PCA分析中可显著区分辐照茶叶的不同辐照量组。表明在辐照茶叶鉴别中电子鼻技术有一定的应用前景。展开更多
基金support from the Doctoral Fund of Ministry of Education of China (No 20070224003)oversea research project of Hei-longjiang Province Education Agency, China (No1151HZ01)research project of Heilongjiang Province Education Agency, China (No 10531002).
文摘Four rice samples of long grain type were tested using an electronic nose (Cyranose-320).Samples of 5 g of each variety of rice were placed individually in vials and were analyzed with the electronic nose unit consisting of 32 polymer sensors.The Cyranose-320 was able to differentiate between varieties of rice.The chemical composition of the rice odors for differentiating rice samples needs to be investigated.The optimum parameter settings should be considered during the Cyranose-320 training process especially for multiple samples,which are helpful for obtaining an accurate training model to improve identification capability.Further,it is necessary to investigate the E-nose sensor selection for obtaining better classification accuracy.A re- duced number of sensors could potentially shorten the data processing time,and could be used to establish an application pro- cedure and reduce the cost for a specific electronic nose.Further research is needed for developing analytical procedures that adapt the Cyranose-320 as a tool for testing rice quality.
基金Project supported by the National Natural Science Foundation of China(Nos.61876059 and U1501251)
文摘An electronic-nose is developed based on eight quartz-crystal-microbalance (QCM) gas sensors in a sensor box, and is used to detect Chinese liquors at room temperature. Each sensor is a highly-accurate and highly-sensitive oscillator that has experienced airflow disturbances under the condition of varying room temperatures due to unstable flow-induced forces on the sensors surfaces. The three-dimensional (3D) nature of the airflow inside the sensor box and the interactions of the airflow on the sensors surfaces at different temperatures are studied by computational fluid dynamics (CFD) tools. Higher simulation accuracy is achieved by optimizing meshes, meshing the computational domain using a fine unstructural tetrahedron mesh. An optimum temperature, 30 ℃, is obtained by analyzing the distributions of velocity streamlines and the static pressure, as well as the flow-induced forces over time, all of which may be used to improve the identification accuracy of the electronic-nose for achieving stable and repeatable signals by removing the influence of temperature.
文摘目的研究不同等级俄色绿茶香气成分的组成及差异。方法采用电子鼻和气相色谱-离子迁移谱法(gas chromatography-ion mobility spectrometry,GC-IMS)对极品(LCJP)、特级(LCTJ)、一级(LCYJ)俄色绿茶的香气物质进行检测,并利用主成分分析(principal component analysis,PCA)法及正交偏最小二乘法判别分析(orthogonal partial least squares discriminant analysis,OPLS-DA)模型评价识别3种不同等级俄色绿茶间的香气差异。结果电子鼻和GC-IMS分析结果均表明3种等级茶叶香气特征有显著差别,其中LCYJ与LCTJ风格相似,而LCJP风格独特。GC-IMS在3种茶样中共检测出39种挥发性成分,主要为酯类、醛类、酮类、醇类物质;OPLS-DA模型筛选得到25个变量重要性投影值(variable importance in the projection,VIP)大于1的特征物质,乙醇、月桂烯在LCJP样本中含量最低,是引起LCJP茶汤香气清淡风味的主要原因之一。结论利用电子鼻结合GC-IMS可实现俄色绿茶不同质量等级的有效甄别,对俄色绿茶的质量化评估具有重要意义,同时该研究可为后续俄色茶资源的开发利用提供一定理论依据。ethyl alcohol and myrcene。
文摘以辐照0、1、3、5 k Gy的黄山毛峰和祁门红茶为研究对象,通过优化电子鼻测茶叶香气的技术参数,并对未辐照和辐照茶叶、辐照茶叶不同辐照剂量组的气味数据进行主成分分析(PCA)和线性判别函数分析(LDA),研究电子鼻技术在茶叶辐照鉴定中的应用效果。结果表明,利用电子鼻技术可显著区分辐照茶叶和未辐照茶叶,区分率为1.000,并且在PCA分析中可显著区分辐照茶叶的不同辐照量组。表明在辐照茶叶鉴别中电子鼻技术有一定的应用前景。
