首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   12篇
  国内免费   1篇
  完全免费   3篇
  轻工业   16篇
  2021年   1篇
  2018年   1篇
  2016年   1篇
  2013年   2篇
  2012年   4篇
  2011年   3篇
  2010年   1篇
  2009年   1篇
  2006年   2篇
排序方式: 共有16条查询结果,搜索用时 187 毫秒
1.
Yande Liu  Xudong Sun  Aiguo Ouyang 《LWT》2010,43(4):602-49
A relationship was established between the soluble solid content (SSC) of navel orange fruit determined by destructive measurement and visible-near infrared diffuse reflectance spectra in the wavelength range of 350-1800 nm. Multiplicative scatter correction (MSC) and standard normal variate correction (SNV) were applied to the spectra, partial least squares regression (PLSR) and back propagation neural network (BPNN) based on principal component analysis (PCA) were used to develop the models for predicting the SSC of intact navel orange fruit. Thirty-eight unknown samples were used to evaluate the performance of these models. The principal component analysis-back propagation (PCA-BPNN) method with MSC spectral pretreatment obtain the best predictive results, resulting in correlation coefficient, root mean square error of prediction (RMSEP), average difference between predicted and measured values (Bias) of 0.90, 0.68 °Brix and 0.16 °Brix, respectively. Experimental results indicate that PCA-BPNN is a suitable tool to model the non-linear complex system, with additional advantages over PLSR, and the vis/NIR spectrometric technique can be used for measuring the SSC of intact navel orange fruit, nondestructively.  相似文献
2.
表面增强拉曼光谱法检测农药残留的研究进展   总被引:4,自引:2,他引:2       下载免费PDF全文
表面增强拉曼光谱技术(SERS)作为一种高灵敏度的指纹光谱技术, 在农药残留检测方面越来越受到关注。本文介绍了表面增强原理, 从表面增强基底、农药的特征拉曼位移、农药残留表面增强拉曼光谱定性判别和定量分析四个方面综述了农药残留SERS检测研究进展, 展望了SERS在农药残留检测方面的应用前景。  相似文献
3.
A portable near-infrared (NIR) device was developed to nondestructively predict Brix value in intact ‘Gannan’ navel oranges. This research focused on developing calibration models which were less disturbed by the challenges of portable applications. The spectra of 150 samples were collected in the wavelength range of 820–950 nm. Wavelet transformed (WT) was applied to compress the raw data for improving the optimization efficiency. Classical linear partial least squares regression and nonlinear least squares support vector regression (LSSVR) were applied to building calibration models. By comparison, both prediction precision and optimization efficiency of the compressed regression models were improved. The LSSVR models outperformed the PLS models with higher accuracy and lower error. LSSVR combined with WT compression (WT–LSSVR) produced the best correlation coefficient value (r) and the root mean squared error of prediction of 0.918 and 0.321 oBrix. Based on these results, WT–LSSVR is to be a promising method to improve precision and optimization efficiency of NIR spectral calibration models for Brix prediction in ‘Gannan’ navel oranges by the portable near-infrared device.  相似文献
4.
表面增强拉曼光谱法在农药残留检测中的研究进展   总被引:1,自引:0,他引:1  
表面增强拉曼光谱是一种探测界面特性、分子之间相互作用和分子结构非常有效的现代测试分析工具,可将试样检测限提高10个数量级.文章介绍表面增强拉曼光谱技术的增强原理、活性基底的制备及其关键技术,综述表面增强拉曼光谱在农药残留分析中的研究进展,分析其优势和不足,并提出表面增强拉曼光谱在农药残留中的发展方向.  相似文献
5.
近红外漫反射无损检测赣南脐橙中可溶性固形物和总酸   总被引:1,自引:0,他引:1  
目的:利用近红外漫反射无损检测技术对赣南脐橙可溶性固形物和总酸含量进行相关研究。方法:通过自行设计的NIR光谱系统测定150个赣南脐橙可溶性固形物和总酸。120个赣南脐橙样品用来建模,其余30个用来验证模型的性能。采集完整赣南脐橙的近红外漫反射光谱(350~1800nm),光谱经移动窗口平滑处理、一阶微分和二阶微分预处理后,再分别采用主成分回归(PCR)和偏最小二乘法(PLS),建立赣南脐橙可溶性固形物和总酸含量的定量预测数学模型。结果:采用一阶微分结合偏最小二乘法所建模型的预测效果较好,可溶性固形物和总酸含量定量预测数学模型的相关系数分别为0.9263和0.9562,均方根误差分别为0.4102°Brix和0.018%。结论:近红外漫反射光谱作为一种无损的检测方法,可用于评价赣南脐橙的可溶性固形物和总酸含量。  相似文献
6.
基于UG的齿轮刀具设计及切齿仿真加工研究   总被引:1,自引:0,他引:1  
黄勇 《食品与机械》2006,22(6):99-102
利用计算机仿真技术,结合计算机图形学技术,在企业普遍使用的UG CAD平台上,对常用齿轮刀具进行参数设计计算并仿真加工齿轮,对形成齿廓的过程进行动态仿真,帮助刀具设计者验证刀具的齿形参数合理与否,减少甚至避免试切,直接降低齿轮的试切、调试费用,缩短试制周期。同时,提出把C/S结构引入到UG二次开发中,实现了MFC、UG/Open和C/S结构三者相结合的应用。  相似文献
7.
基于多重自相关微弱正弦信号的检测   总被引:1,自引:0,他引:1  
陈明奎  刘正平 《轻工机械》2006,24(3):112-115
强噪音背景下检测出有用的正弦信号是信号检测中的一个典型问题。本文介绍的多重自相关法利用了正弦函数的特性,经过多重自相关运算,再对信号进行频谱分析,就能准确检测出湮没于强大噪声的微弱正弦信号,其中频率信息精确,幅值信息经过修正后也能达到一定精度。  相似文献
8.
Near-infrared (NIR) spectroscopy has been attempted to determine ash and moisture of wheat flour nondestructively combined with characteristic bands selection methods. Pearson product-moment correlation coefficients and interval partial least squares (iPLS) were performed comparatively to choose characteristic bands associated with ash and moisture distributions. Through comparing the performance of developed models with new samples, the optimal models of ash and moisture were obtained with the characteristic bands of 4000–5500, 6708–7304 and 4000–4896, 5504–6704 cm?1, respectively. The root mean square errors of prediction were 0.019 and 0.088 % for ash and moisture, respectively. The results suggest that NIR technique combining with iPLS has significant potential to quantitatively analyze ash and moisture in wheat flour; moreover, it could indicate the related spectral contributions.  相似文献
9.
研究了以蒸馏水为提取剂从油茶壳中提取单宁的工艺。在单因素实验的基础上,运用Box-Behnken中心组合实验和响应面法考察了液料比、提取温度和提取时间3个因素对单宁含量的影响,并优化了提取工艺。结果表明,最佳的工艺条件为:液料比30(mL.g-1),提取温度63℃,提取时间26min。在此条件下,单宁含量的预测值为4.28%,验证实验值为4.25%,两者相近,说明响应面法优化油茶壳中单宁的提取工艺可行。  相似文献
10.
刘燕德  张光伟 《食品与机械》2012,28(5):223-226,242
介绍高光谱成像技术的原理,总结高光谱在农药残留、农作物品质、肉类品质检测中的应用,并分析其中的不足和优势,提出高光谱成像技术未来在农产品检测中的发展方向。  相似文献
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号