To evaluate the potential of FT-NIR spectroscopy and the influence of the distance between the light source/detection probe and the fruit for measuring the sugar content (SC) of Fuji apples, diffuse reflectance spectr...To evaluate the potential of FT-NIR spectroscopy and the influence of the distance between the light source/detection probe and the fruit for measuring the sugar content (SC) of Fuji apples, diffuse reflectance spectra were measured in the spectral range from 12500 to 4000 cm^-1 at 0 mm, 2 mm, 4 mm and 6 mm distances. Four calibration models at four distances were established between diffused reflectance spectra and sugar content by partial least squares (PLS) analysis. The correlation coefficients (R) of calibrations ranged from 0.982 to 0.997 with SEC values from 0.138 to 0.453 and the SECV values from 0.74 to 1.58. The best model of original spectra at 0 mm distance yielded high correlation determination of 0.918, a SEC of 0.092, and a SEP of 0.773. The results showed that different light/detection probe-fruit distances influence the apple reflective spectra and SC predictions.展开更多
We analyzed two types of crude oil samples: Middle Eastern crude oil and Texas crude oil by using a residual gas analyzer (RGA) based on the linear quadrupole principle. This portable mass analyzer is capable of measu...We analyzed two types of crude oil samples: Middle Eastern crude oil and Texas crude oil by using a residual gas analyzer (RGA) based on the linear quadrupole principle. This portable mass analyzer is capable of measuring hydrocarbons with masses of up to 300 atomic mass units (amu) as well as low mass targets, such as methane and carbon dioxide at ppm level concentrations. The generated mass spectra revealed differences in the composition and signal intensity of hydrocarbons of Middle Eastern and Texas crude oil samples. Even if RGA 300 is manufactured to be served as a detailed gas analysis of vacuum systems, we have shown that it is sensitively capable of detection of hydrocarbons and it enables one to qualitative and quantitative analysis of the composition of the crude oils.展开更多
为了探究中国数字内容贸易出口规模和结构特征等问题,借鉴联合国贸易和发展会议(United Nations Conference on Trade and Development,UNCTAD)的测算思路,对中国与世界范围内135个主要经济体开展的数字内容贸易出口规模进行测算。除贸...为了探究中国数字内容贸易出口规模和结构特征等问题,借鉴联合国贸易和发展会议(United Nations Conference on Trade and Development,UNCTAD)的测算思路,对中国与世界范围内135个主要经济体开展的数字内容贸易出口规模进行测算。除贸易总额外,还分别测算了数字视听、数字游戏和数字图书3个不同类别数字内容产品的出口金额;更进一步地,对中国数字内容贸易的总体发展趋势、主要出口对象、对不同出口对象的主力贸易产品进行分析。研究认为,欧盟、美国、日本及韩国等经济体是中国数字内容贸易最主要的出口对象;数字游戏和数字视听是中国主要的贸易产品,其中数字游戏在海外有更强的竞争力;受限于消费者偏好以及互联网发展水平等多重因素影响,不同经济体的消费者对于中国不同类别数字内容产品喜好存在较大差异,如日韩及北美消费者更偏好数字游戏、中国其他地方的消费者则更偏好于数字视听。研究表明,面对数字内容贸易迅速发展的现实情况,中国应该积极参与国际数字贸易治理,提升数字贸易规则制定的话语权,尽早建立国际统一的数字贸易规则;加强文化和科技的融合,进一步提升中国数字内容产品的国际竞争力,向价值链高端延伸;针对不同类别的数字内容产品,有针对性的制定出口推广策略,如提升翻译质量、举办文化交流活动、关注新兴市场等。展开更多
基金Project (No. 30270763) supported by the National Natural Science Foundation of China
文摘To evaluate the potential of FT-NIR spectroscopy and the influence of the distance between the light source/detection probe and the fruit for measuring the sugar content (SC) of Fuji apples, diffuse reflectance spectra were measured in the spectral range from 12500 to 4000 cm^-1 at 0 mm, 2 mm, 4 mm and 6 mm distances. Four calibration models at four distances were established between diffused reflectance spectra and sugar content by partial least squares (PLS) analysis. The correlation coefficients (R) of calibrations ranged from 0.982 to 0.997 with SEC values from 0.138 to 0.453 and the SECV values from 0.74 to 1.58. The best model of original spectra at 0 mm distance yielded high correlation determination of 0.918, a SEC of 0.092, and a SEP of 0.773. The results showed that different light/detection probe-fruit distances influence the apple reflective spectra and SC predictions.
文摘We analyzed two types of crude oil samples: Middle Eastern crude oil and Texas crude oil by using a residual gas analyzer (RGA) based on the linear quadrupole principle. This portable mass analyzer is capable of measuring hydrocarbons with masses of up to 300 atomic mass units (amu) as well as low mass targets, such as methane and carbon dioxide at ppm level concentrations. The generated mass spectra revealed differences in the composition and signal intensity of hydrocarbons of Middle Eastern and Texas crude oil samples. Even if RGA 300 is manufactured to be served as a detailed gas analysis of vacuum systems, we have shown that it is sensitively capable of detection of hydrocarbons and it enables one to qualitative and quantitative analysis of the composition of the crude oils.
文摘为了探究中国数字内容贸易出口规模和结构特征等问题,借鉴联合国贸易和发展会议(United Nations Conference on Trade and Development,UNCTAD)的测算思路,对中国与世界范围内135个主要经济体开展的数字内容贸易出口规模进行测算。除贸易总额外,还分别测算了数字视听、数字游戏和数字图书3个不同类别数字内容产品的出口金额;更进一步地,对中国数字内容贸易的总体发展趋势、主要出口对象、对不同出口对象的主力贸易产品进行分析。研究认为,欧盟、美国、日本及韩国等经济体是中国数字内容贸易最主要的出口对象;数字游戏和数字视听是中国主要的贸易产品,其中数字游戏在海外有更强的竞争力;受限于消费者偏好以及互联网发展水平等多重因素影响,不同经济体的消费者对于中国不同类别数字内容产品喜好存在较大差异,如日韩及北美消费者更偏好数字游戏、中国其他地方的消费者则更偏好于数字视听。研究表明,面对数字内容贸易迅速发展的现实情况,中国应该积极参与国际数字贸易治理,提升数字贸易规则制定的话语权,尽早建立国际统一的数字贸易规则;加强文化和科技的融合,进一步提升中国数字内容产品的国际竞争力,向价值链高端延伸;针对不同类别的数字内容产品,有针对性的制定出口推广策略,如提升翻译质量、举办文化交流活动、关注新兴市场等。