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在线紫外分光分析仪的研制
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作者 白万红 漆随平 陈军 《甘肃科技》 1998年第2期13-14,共2页
在线紫外分析仪是用来对石油化工产品进行紫外光谱分析的线检测仪表,该仪表由双单色仪,紫外光源,高灵敏的检测系统等组成。测试系统用短光程吸收池,差试光谱法,对吸光度高达7Abs的石油产品,不经稀释即可进行在线检测。突破了... 在线紫外分析仪是用来对石油化工产品进行紫外光谱分析的线检测仪表,该仪表由双单色仪,紫外光源,高灵敏的检测系统等组成。测试系统用短光程吸收池,差试光谱法,对吸光度高达7Abs的石油产品,不经稀释即可进行在线检测。突破了以往采用现场采样,实验室稀释,普通... 展开更多
关键词 在线紫外分析仪 紫外分光分析仪 油品分析
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红外分光油分析仪的设计与研究
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作者 倪争技 黄元申 《光学仪器》 2002年第3期14-19,共6页
描述了红外分光油分析仪的基础原理、结构和数学模型 ,着重介绍了红外测油的原理。
关键词 红外分析仪 红外探测器 PLC 波数
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分光光度法-流动注射分析仪校准方法的研究
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作者 施江焕 余善成 王维峰 《中国测试》 CAS 北大核心 2012年第S1期56-57,共2页
为保证水质监测数据的准确性和统一性,结合分光光度法-流动注射分析仪的工作原理,通过长期的实践摸索,对该类仪器进行系统的测试和论证,研究并建立一套可靠的校准方法,解决目前缺乏该类仪器校准规范的问题。该方法科学、合理、可操作性... 为保证水质监测数据的准确性和统一性,结合分光光度法-流动注射分析仪的工作原理,通过长期的实践摸索,对该类仪器进行系统的测试和论证,研究并建立一套可靠的校准方法,解决目前缺乏该类仪器校准规范的问题。该方法科学、合理、可操作性强,各项计量性能评价指标符合仪器的设计性能及实际测试工作要求,对计量检定机构开展该类仪器的校准工作有一定的指导意义。 展开更多
关键词 度法-流动注射分析仪 检出限 线性误差 计量性能 校准方法
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钢液直接分析法的展望
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作者 佐伯正夫 谢德 《包钢科技》 1991年第1期75-80,共6页
在钢铁生产过程中,目前还是用取样—冷却—制样的程序进行数值分析或用发光分光分析仪等进行分析管理。如能对钢水进行直接分析,对实现炼钢工序的合理化和自动化将是一大促进。这个在过去只能是说说而已的设想,不久即将得以实现。
关键词 直接分析 分光分析仪 炼钢工序 数值分析 钢铁生产过程 制样 炼钢工艺 炼钢过程 钢液面 现场试验
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Feature extraction for target identification and image classification of OMIS hyperspectral image 被引量:7
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作者 DU Pei-jun TAN Kun SU Hong-jun 《Mining Science and Technology》 EI CAS 2009年第6期835-841,共7页
In order to combine feature extraction operations with specific hyperspectral remote sensing information processing objectives,two aspects of feature extraction were explored. Based on clustering and decision tree alg... In order to combine feature extraction operations with specific hyperspectral remote sensing information processing objectives,two aspects of feature extraction were explored. Based on clustering and decision tree algorithm,spectral absorption index (SAI),continuum-removal and derivative spectral analysis were employed to discover characterized spectral features of different targets,and decision trees for identifying a specific class and discriminating different classes were generated. By combining support vector machine (SVM) classifier with different feature extraction strategies including principal component analysis (PCA),minimum noise fraction (MNF),grouping PCA,and derivate spectral analysis,the performance of feature extraction approaches in classification was evaluated. The results show that feature extraction by PCA and derivate spectral analysis are effective to OMIS (operational modular imaging spectrometer) image classification using SVM,and SVM outperforms traditional SAM and MLC classifiers for OMIS data. 展开更多
关键词 hyperspectral remote sensing feature extraction decision tree SVM OMIS
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Effects of water salinity and content on particle size distribution and soil strength
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作者 PENG Chang-sheng LOWG Kathleen ZHANG Qian 《Journal of Environmental Science and Engineering》 2009年第1期24-28,共5页
The effect of NaCl on soil strength was investigated in this project based on salinity concentrations of 0 g/L, 5 g/L, 20 g/L, and 50 g/L as well as varying water contents of 15%-20%. Laser particle size analyzer was ... The effect of NaCl on soil strength was investigated in this project based on salinity concentrations of 0 g/L, 5 g/L, 20 g/L, and 50 g/L as well as varying water contents of 15%-20%. Laser particle size analyzer was also performed to explain possible effects. From particle size analysis and strength tests, it is hypothesized that the strength of the soil is increased with the addition of certain salinity concentrations until there are reversed effects, which is between 20 g/L and 50 g/L from our study. The increase of strength is suggested to be the affect of a greater variety of particle sizes. Since NaCI plays a role in the particle size distribution, it also plays a role in the strength of soils. The degree of the effect of the water content also differs from concentrations, and could be due to the variation of hydration film thickness on particles, which is affected by the ions introduced from water. 展开更多
关键词 water salinity water content particle size distribution soil strength hydration film
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Classification of Barley according to Harvest Year and Species by Using Mid-infrared Spectroscopy and Multivariate Analysis
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作者 Ajib Budour Fournier Frantz +2 位作者 Boivin Patrick Schmitt Marc Fick Michel 《Journal of Food Science and Engineering》 2014年第1期36-54,共19页
In order to monitor malt quality in the malting industry, despite yearly variations in the barley quality, 394 barley samples were analysed using conventional (moisture, protein and B-glucan content) and mid-infrare... In order to monitor malt quality in the malting industry, despite yearly variations in the barley quality, 394 barley samples were analysed using conventional (moisture, protein and B-glucan content) and mid-infrared Fourier transform spectroscopy FT-IR. The experimental dataset included barley from three harvest years, two barley species, 77 barley varieties, and two-row and six-row barley, from 16 cultivation sites. For each sample, the malt quality indices were also assessed according to European Brewing Convention (EBC) standards. Principal component analysis (PCA) was carried out on mean-centred, normalized and derivative spectra using 200/cm width spectral bands. The most informative spectral bands were observed in the 800-1,000/cm and 1,000-1,200/cm ranges. PCA revealed that barley harvested in 2010 and in 2011 had bands that were very close together, while 2009 harvest clearly displayed a difference in its quality. PCA made it possible to distinguish two species and confirmed that two-row winter barley quality was closer to two-row spring barley quality than to six-row winter barley. Results indicate that mid-infrared spectrometry (MIR) could be a very useful and rapid analytical tool to assess barley qualitative quality. 展开更多
关键词 Malting barley mean infrared spectroscopy principal components analysis.
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Cross-Validation of a Mobile N20 Flux Prototype (IPNOA) Using Micrometeorological and Chamber Methods
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作者 Patricia Laville Simone Neri +3 位作者 David Continanza Luca Ferrante Vero Simona Bosco Giorgio Virgili 《Journal of Energy and Power Engineering》 2015年第4期375-385,共11页
Within a LIFE+ project IPNOA (improved flux prototype for n2o emission from agriculture), LIFE11 ENV/IT/302 is a mobile prototype was developed to evaluate at field scale N20 emissions using a fast chamber techniqu... Within a LIFE+ project IPNOA (improved flux prototype for n2o emission from agriculture), LIFE11 ENV/IT/302 is a mobile prototype was developed to evaluate at field scale N20 emissions using a fast chamber technique. Main challenge was to develop a mobile system capable of moving on various field surfaces, equipped with very reliable N20 gas analyser (Los Gatos Research Inc.), electrically autonomous (with batteries) and enough robust to face up to field conditions. In this paper, we report the major features of this prototype studied during two field campaigns. The N20 flux IPNOA prototype was compared with other methodological implementations: first, during an INGOS (integrated non-CO2 greenhouse gas observing systems) campaign on a grazed grassland at Easter Bush (Scotland) by Eddy correlation method, and then after on an arable crop at Grignon (France) using automatic and manual chambers fitted with QC-TILDAS (Quantum Cascade Tunable Infrared Laser Differential Absorption Spectrometer, Aerodyne Research Inc.), with the 46C model of thermo-instrument analyser or with a GC (gas chromatography) analysis. 展开更多
关键词 Monitoring device nitrous oxide inventory agricultural managements steady state chamber.
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Numerical Analysis of the Biogeochemical Parameters in the Bay of Bengal
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《Journal of Shipping and Ocean Engineering》 2016年第3期135-148,共14页
Oceanic nutrient cycling plays a key role in understanding how oceanic biogeochemical parameters respond in varying physical and anthropogenically controlled processes. OA (Objective Analysis) of monthly climatology... Oceanic nutrient cycling plays a key role in understanding how oceanic biogeochemical parameters respond in varying physical and anthropogenically controlled processes. OA (Objective Analysis) of monthly climatology of WOAI3 (World Ocean Atlas 13) nutrient data of 5 km resolution called Nutrient-Climo has been done in this paper for analyzing the nutrient-rich region in the BOB (Bay of Bengal) and the mechanisms of physical forces were examined using six years (2002-2007) global ocean monthly analysis datasets based on the SODA v2.0.4 (Simple Ocean Data Assimilation package). The upwelled zones established from the circulation pattern were well synchronized with the nitrate rich zones. The POC (particulate organic carbon) of 5 km resolution has been analyzed from MODIS (Moderate-resolution Imaging Spectroradiometer) data and Chl a (Chlorophyll a) concentration SeaWiFS (Sea-viewing Wide Field-of-view Sensor) data of 9 km resolution are used to predict the productive zones in the BOB. In this paper, we examined that Chl a concentration (above 0.5 mg/m3) is found during the post-monsoon followed by winter in the north-western, north-eastern coast and head BOB as the source of nutrients is also supplementary due to high input of litter and sediment associated nutrients that are released during estuarine transport. 展开更多
关键词 OA Nutrient-Climo Chl a POC MODIS ScaWiFS.
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Using Support Vector Regression to Analyze Urban Atmosphere Pollution with Optical Remote Sensing Data
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作者 Yansong Xue Le Yu +1 位作者 Kai Cao Pengwei XH 《Journal of Earth Science and Engineering》 2013年第3期180-189,共10页
The concentration of absorbable particulate matter less than 10 μm termed as PM10 is the most important urban air pollution index for air quality monitoring. This paper presents a space based PM10 monitoring algorith... The concentration of absorbable particulate matter less than 10 μm termed as PM10 is the most important urban air pollution index for air quality monitoring. This paper presents a space based PM10 monitoring algorithm based on QUAC (QUick atmosphere correction) for optical remote sensing data and SVR (support vector regression). PM 10 concentration measurements from nine ground based stations in Hangzhou, China and the MODIS (moderate-resolution imaging spectroradiometer) images were analyzed. Experimental result indicates that the correlation between CD (correction differences) with actual measured data is better than correlation between AOD (aerosol optical depth) with measured data. In addition, the fitting performance of the SVR model established with CD and measured data is better than traditional regression models. 展开更多
关键词 MODIS PMIO QUAC SVR.
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Monitoring air pollution in China from geostationary satellite: A synthetic study using simulated observations
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作者 Xi CHEN Zhaonan CAI +1 位作者 Yi LIU Dongxu YANG 《Science China Earth Sciences》 SCIE EI CAS CSCD 2018年第11期1622-1632,共11页
We simulated geostationary satellite observations to assess the potential for high spatial-and temporal-resolution monitoring of air pollution in China with a focus on tropospheric ozone(O_3), nitrogen dioxide(NO_2), ... We simulated geostationary satellite observations to assess the potential for high spatial-and temporal-resolution monitoring of air pollution in China with a focus on tropospheric ozone(O_3), nitrogen dioxide(NO_2), sulfur dioxide(SO_2), and formaldehyde(HCHO). Based on the capabilities and parameters of the payloads onboard sun-synchronous satellites, we simulated the observed spectrum based on a radiative transfer model using a geostationary satellite model. According to optimal estimation theory, we analyzed the sensitivities and retrieval uncertainties of the main parameters of the instrument for the target trace gases. Considering the retrieval error requirements of each trace gas, we determined the major instrument parameter values(e.g., observation channel, spectral resolution, and signal-to-noise ratio). To evaluate these values, retrieval simulation was performed based on the three-dimensional distribution of the atmospheric components over China using an atmospheric chemical transportation model. As many as 90% of the experiments met the retrieval requirements for all target gases. The retrieval precision of total-column and stratospheric O_3 was 2%. In addition, effective retrieval of all trace gases could be achieved at solar zenith angles larger than 70°. Therefore, the geostationary satellite observation and instrument parameters provided herein can be used in air pollution monitoring in China. This study offers a theoretical basis and simulation tool for improving the design of instruments onboard geostationary satellites. 展开更多
关键词 Air pollution Geostationary satellite Instrument parameters Retrieval error
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