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程序升温气相色谱对农药复配制剂的分析 被引量:2
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作者 毕富春 王文丽 《农药》 CAS 北大核心 1989年第2期17-18,5,共3页
目前农药复配制剂日益增多,在国际农药市场上,美国和日本的复配制剂占其总产量的近一半,其他国家也有众多的复配品种不断投放市场。对这些复配品种虽然有的仍可用恒温气相色谱进行分析,但是对这些制剂中沸点等性质相差很大的组份,就很... 目前农药复配制剂日益增多,在国际农药市场上,美国和日本的复配制剂占其总产量的近一半,其他国家也有众多的复配品种不断投放市场。对这些复配品种虽然有的仍可用恒温气相色谱进行分析,但是对这些制剂中沸点等性质相差很大的组份,就很难用恒温色谱对其中的有效成分同时进行分离。程序升温色谱法用于农药制剂的分析,在我国尚较少。目前我国生产的复配农药品种日益增多,同时我国生产的几种主要的气相色谱仪也都配置了程序升温装置,为程序升温色谱法在农药复配制剂中的应用创造了有利条件。 展开更多
关键词 程序升温 复配制剂 中沸点 气相 农药制剂 农药品种 拌种灵 克百威 组份 初始温度
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用指数程序涂渍色谱柱测定油脂的脂肪酸 被引量:1
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作者 唐大武 叶翠层 +1 位作者 聂长明 刘小林 《中南林学院学报》 CSCD 1991年第2期158-161,共4页
本文提出了一种按指数程序涂渍的气相色谱柱测定油脂肪脂酸的方法,实验表明,以DEGS为固定液,液载比按y=2.05×14^2变化的四段2米指数柱的柱效,塔板高度,硬脂肪酸甲酯与油酸甲酯与油酸甲酯的分离度及分析菜籽油所需的时间,均... 本文提出了一种按指数程序涂渍的气相色谱柱测定油脂肪脂酸的方法,实验表明,以DEGS为固定液,液载比按y=2.05×14^2变化的四段2米指数柱的柱效,塔板高度,硬脂肪酸甲酯与油酸甲酯与油酸甲酯的分离度及分析菜籽油所需的时间,均比液载比为5.0%的2米均柱优越,说明此法更适于对油脂,特别是含高碳数脂肪酸的油脂进行分析。 展开更多
关键词 指数程序涂渍谱柱 柱效 油脂分析 脂肪酸
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余弦函数程序涂渍色谱柱的研究
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作者 袁晓燕 易卫红 陈贻文 《湖南大学学报(自然科学版)》 EI CAS CSCD 1999年第3期21-24,93,共5页
程序涂渍色谱柱内固定液和载体的比例按余弦函数程序改变.从理论上推导出程序效应与各变数之间的关系,对其色谱柱的特性进行了探讨.
关键词 气相谱法 余弦函数程序 程序涂渍谱柱
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等差线性程序涂渍色谱柱的研究
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作者 易卫红 陈贻文 李庆宏 《湖南大学学报(自然科学版)》 EI CAS CSCD 1996年第4期51-55,共5页
设计了等差线性程序柱,从理论上推导出等差线性程序柱中组分的保留时间与各操作参数之间的数学关系式,并对其色谱特性及应用进行了探讨.
关键词 程序涂渍谱柱 气相谱法 特性
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程序涂渍色谱柱的研究及应用 被引量:1
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作者 成金玉 张荣水 《华东冶金学院学报》 1995年第4期392-399,共8页
本文对单指数、双指数和新型双指数程序柱进行了研究。选择了指数u=1.6(1.2)、V=0.5的新型双程序柱,采用内标标准曲线法,对酒中高级醇进行了定量分析,该柱保留时间短,柱效高,分离度好。
关键词 幂指数 程序涂渍谱柱 谱分析
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对于有序聚类程序包ZONATION中几个算法的分析与应用实例 被引量:1
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作者 邢雪 童国榜 林锦璇 《石油实验地质》 CAS CSCD 北大核心 1991年第1期93-98,共6页
本文对有序聚类程序色ZONAION(“分带”)中所用的三种算法(其中两个算法各含两种度量指标)进行了介绍与剖析,并以天津Ⅰ24孔钴井中的孢粉序列分析为例对方法进行了验证。
关键词 有序聚类 程序色 岩芯 ZONATION
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移动子窗口搜索法在紫丁香挥发油气相色谱-质谱分析中的应用 被引量:3
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作者 赵晨曦 梁逸曾 +1 位作者 方洪壮 李晓宁 《分析化学》 SCIE EI CAS CSCD 北大核心 2006年第U09期179-182,共4页
基于气相色谱-质谱仪产生的二维数据,采用移动子窗口搜索法,以纯组分峰为标准对同一样品在不同色谱柱上或不同样品在相同色谱柱上所获得的总离子流图的一定保留时间范围内搜索,可以得到目标化合物的流出区域,取其中点作为保留时间... 基于气相色谱-质谱仪产生的二维数据,采用移动子窗口搜索法,以纯组分峰为标准对同一样品在不同色谱柱上或不同样品在相同色谱柱上所获得的总离子流图的一定保留时间范围内搜索,可以得到目标化合物的流出区域,取其中点作为保留时间,从而计算各化合物在不同极性色谱柱上的程序升温保留指数。采用GC-MS与色谱保留指数相结合的方法,分别在HP-5MS和DB-35MS柱上,于80℃~290℃(4℃/min)的升温程序下,对黑龙江产紫丁香花蕾与花挥发油的分析结果表明,辅以化学计量学方法和双柱色谱保留指数定性比单用GC-MS定性结果更加快速可靠。 展开更多
关键词 气相谱-质谱 移动子窗口搜索法 程序升温谱保留指数 紫丁香 挥发油
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白色珠光漆工艺调试及色差解决 被引量:1
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作者 史亚邦 王奇 +1 位作者 郑永帅 张存乐 《现代涂料与涂装》 CAS 2019年第9期38-41,44,共5页
详细介绍了白色珠光漆色差的主要影响因素以及解决办法。通过过程排查发现中涂换色异常时珠光白色漆会出现色差,验证了中涂机器人换色清洗程序对色差的影响。
关键词 珠光漆 程序
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基于FANUC P500浅析喷涂机器人换色系统 被引量:3
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作者 李梁 《现代涂料与涂装》 CAS 2015年第10期53-55,共3页
从换色组件与换色程序等方面介绍了喷涂机器人FANUC P500的换色系统。并且根据现场使用经验,总结了由于换色系统而产生溅溶剂的原因。
关键词 喷涂机器人 系统 组件 程序 溅溶剂
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Determination of Chlorine and Bromine in Plant Materials by Ion Chromatography 被引量:1
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作者 胡兰 陈波 《Agricultural Science & Technology》 CAS 2016年第10期2403-2405,共3页
A method was developed for determination of chlorine and bromine in plant materials by ion chromatography using temperature programing-semi molten for sample preparation. Values of detection limits of the method found... A method was developed for determination of chlorine and bromine in plant materials by ion chromatography using temperature programing-semi molten for sample preparation. Values of detection limits of the method found were 1.0×10^-5 for CI and 1.3×10^-6 for Br. The measuring range of the method found were 0.3-20.0 mg/L for CI and 4,0-120,0 μg/L for Br. The results obtained agreed quite well with those reference values. 展开更多
关键词 Ion chromatography Temperature programing-semi molten PLANT CHLORINE BROMINE
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Automatic salient object segmentation using saliency map and color segmentation 被引量:1
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作者 HAN Sung-ho JUNG Gye-dong +2 位作者 LEE Sangh-yuk HONG Yeong-pyo LEE Sang-hun 《Journal of Central South University》 SCIE EI CAS 2013年第9期2407-2413,共7页
A new method for automatic salient object segmentation is presented.Salient object segmentation is an important research area in the field of object recognition,image retrieval,image editing,scene reconstruction,and 2... A new method for automatic salient object segmentation is presented.Salient object segmentation is an important research area in the field of object recognition,image retrieval,image editing,scene reconstruction,and 2D/3D conversion.In this work,salient object segmentation is performed using saliency map and color segmentation.Edge,color and intensity feature are extracted from mean shift segmentation(MSS)image,and saliency map is created using these features.First average saliency per segment image is calculated using the color information from MSS image and generated saliency map.Then,second average saliency per segment image is calculated by applying same procedure for the first image to the thresholding,labeling,and hole-filling applied image.Thresholding,labeling and hole-filling are applied to the mean image of the generated two images to get the final salient object segmentation.The effectiveness of proposed method is proved by showing 80%,89%and 80%of precision,recall and F-measure values from the generated salient object segmentation image and ground truth image. 展开更多
关键词 salient object visual attention saliency map color segmentation
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Modeling and Analyzing Web Application with Aspect-Oriented Hierarchical Coloured Petri Nets 被引量:1
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作者 Xiaoxing Sun Huiqun Yu +1 位作者 Honghao Liang Nianhua Yang 《China Communications》 SCIE CSCD 2016年第5期89-102,共14页
Aspect-oriented modeling can uncover potential design faults, yet most existing work fails to achieve both separation and composition in a natural and succinct way. This study presents an aspect-oriented modeling and ... Aspect-oriented modeling can uncover potential design faults, yet most existing work fails to achieve both separation and composition in a natural and succinct way. This study presents an aspect-oriented modeling and analysis approach with hierarchical Coloured Petri Nets(HCPN). HCPN has sub-models and well-defined semantics combining a set of submodels. These two characteristics of HCPN are nicely integrated into aspect oriented modeling. Submodels are used to model aspects while the combination mechanism contributes to aspects weaving. Furthermore, the woven aspect oriented HCPN model can be simulated and analyzed by the CPN Tools. A systematic web application case study is conducted. The results show the system original properties are satisfied after weaving aspects and all design flaws are revealed. As such, the approach can support web application design and analysis in an aspect-oriented fashion concisely and effectively. 展开更多
关键词 aspect-oriented modeling hierarchical coloured Petri net CPN Tools ASKCTL
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Low Temperature Dyeing and Shrinkage-Resistance Finishing of Wool by Composition of Salt-Ammonia and Enzyme Treatment
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作者 罗燕 朱若英 +2 位作者 张健飞 滑均凯 忻浩忠 《Journal of Donghua University(English Edition)》 EI CAS 2007年第2期192-196,共5页
Wool top and knitted fabric were treated with ammonia in the presence of sodium chloride (salt-ammonia process). The effectiveness of salt-ammonia process traditionally used as pretreatment for low temperature dyein... Wool top and knitted fabric were treated with ammonia in the presence of sodium chloride (salt-ammonia process). The effectiveness of salt-ammonia process traditionally used as pretreatment for low temperature dyeing has been investigated for conferring shrink-resistance of wool. The pretreatmont of salt-ammonia process followed by enzymatic treatment has been proved that contribute to not only the enhancement of dyeing behavionr but also shrinkage-resistance in the present studies. A novel composition of salt-ammonia pretreatment, oxidized and reduced treatment as well as protease modification was recommended to achieve low temperature dyeing and shrinkage-resistance of wool. At the same time, the process conditions were optimized by orthogonal array and assessed by dye uptake rate, weight loss and area shrinkage. Laboratory experiments showed that the knitted fabric treated according to optimized conditions of the combined process, achieved not only improvement of dye abilities but also the strict requirement of machine-washable, representing a possible alternative to chlorination. 展开更多
关键词 salt-ammonia process ENZYME shrinkagebehaviour dyeing properties
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An optimized sequential extraction scheme for molybdenum association in environmental samples 被引量:1
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作者 Liang Liang Jian-Ming Zhu 《Acta Geochimica》 EI CAS CSCD 2016年第2期111-119,共9页
By comparing three sequential extraction pro- cedures, a new optimized extraction scheme for the molyb- denum association in environmental samples was proposed. Five operational steps were described as exchangeable (... By comparing three sequential extraction pro- cedures, a new optimized extraction scheme for the molyb- denum association in environmental samples was proposed. Five operational steps were described as exchangeable (KH2PO4 + K2HPO4: including water-soluble), associated with organic matter (NaOH), Fe-Mn oxides and/or carbonates (HC1), sulfides (H2O2) and residue (HNO3 + HF + H2O2). An optimized extraction scheme was com- pared with Tessier's procedure and the Commission of European Communities Bureau of Reference (BCR) was applied to black shales. Results showed Tessier's procedure gave the lowest concentration values for exchangeable molybdenum and the highest values for the residual molybdenum, which could not present the efficiency of the extraction reagents. BCR's procedure showed the highest values in oxidizable molybdenum and presented four fractions of molybdenum, which did not demonstrate the fractions of molybdenum in the black shales in detail. The optimized extraction scheme demonstrated a certain improvement on extraction efficiency over Tessier's proce- dure for the lowest residual molybdenum, and revealed morefeatured fraction information of molybdenum in black shales than BCR' s. Therefore, after a comparison with other two extraction procedures, the optimized extraction scheme proved suitable for the molybdenum in black shales and it also showed an accurate determination of the molybdenum in the fractions and source of bioavailable Mo. 展开更多
关键词 MOLYBDENUM Sequential extractionprocedure Black shales
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Nuclear reprogramming: the zygotic transcription program is established through an“erase-and-rebuild” strategy 被引量:5
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作者 Feng Sun Haiyan Fang +5 位作者 Ruizhen Li Tianlong Gao Junke Zheng Xuejin Chen Wenqin Ying Hui Z Sheng 《Cell Research》 SCIE CAS CSCD 2007年第2期117-134,共18页
Oocytes display a maternal-specific gene expression profile, which is switched to a zygotic profile when a haploid set of chromatin is passed on to the fertilized egg that develops into an embryo. The mechanism underl... Oocytes display a maternal-specific gene expression profile, which is switched to a zygotic profile when a haploid set of chromatin is passed on to the fertilized egg that develops into an embryo. The mechanism underlying this transcription reprogramming is currently unknown. Here we demonstrate that by the time when transcription is shut down in germinal vesicle oocytes, a range of general transcription factors and transcriptional regulators are dissociated from the chromatin. The global dissociation of chromatin factors (CFs) disrupts physical contacts between the chromatin and CFs and leads to erasure of the maternal transcription program at the functional level. Critical transcription factors and regulators remain separated from chromatin for a prolonged period, and become re-associated with chromatin shortly after pronuclear formation. This is followed temporally by the re-establishment of nuclear functions such as DNA replication and transcription. We propose that the maternal transcription program is erased during oogenesis to generate a relatively naive chromatin and the zygotic transcription program is rebuilt de novo after fertilization. This process is termed as the "erase-and-rebuild" process, which is used to reset the transcription program, and most likely other nuclear processes as well, from a maternal one to that of the embryo. We further show in the accompanying paper (Gao T, et al., Cell Res 2007; 17:135-150.) that the same strategy is also employed to reprogram transcriptional profiles in somatic cell nuclear transfer and parthenogenesis, suggesting that this model is universally applicable to all forms of transcriptional reprogramming during early embryogenesis. Displacement of CFs from chromatin also offers an explanation for the phenomenon of transcription silence during the maternal to zygotic transition. 展开更多
关键词 nuclear reprogramming TRANSCRIPTION transcription silence chromatin factors EMBRYOGENESIS FERTILIZATION OOGENESIS
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说明
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作者 编辑部 《刑事技术》 1987年第4期44-,共1页
本刊今年第1期第5页左栏图的图号和图题名应为'图4.三磷杀虫剂程序升温色谱图',图注第l行应为'色谱柱:OV-101 20米×0.35毫米毛细管柱';第23页图4的图注2.应为'荧光接收透过光谱'。该期有的刊本中,
关键词 图号 程序升温 毛细管柱
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Skin Detection Using Simple Arithmetic Operations
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作者 Saleh Alshehri 《Computer Technology and Application》 2012年第12期797-800,共4页
Skin detection is the primary step in a large number of computer vision applications. Speed and simplicity are vital components in many of these applications. Various methods have been implemented. However they lack e... Skin detection is the primary step in a large number of computer vision applications. Speed and simplicity are vital components in many of these applications. Various methods have been implemented. However they lack either speed or simplicity or both. In previous studies, simple color component subtraction and threshold in RGB color space were used. However, in this research study, the threshold is found empirically using a known images database. In addition, all the RGB color components were used in the calculation. Optimistic results were obtained. The obtained results illustrate that this method is a promising approach used in skin detection applications. 展开更多
关键词 Skin detection RGB color space.
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Comparative Study on Woody Biomass Use and Application in Japanese Biomass Towns
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作者 Kayoko Yamamoto Jun Izumi Shifeng Zhang 《Journal of Environmental Science and Engineering(B)》 2013年第2期82-94,共13页
This study aimed to grasp the characteristics of woody biomass use and application in leading examples of Japanese biomass towns, and made the following two points clear: (1) Biomass town plans had been officially ... This study aimed to grasp the characteristics of woody biomass use and application in leading examples of Japanese biomass towns, and made the following two points clear: (1) Biomass town plans had been officially announced in 318 districts by 2011, and in about 71% of the districts, woody biomass use and application, which is classified into four types, was being conducted; (2) In each example studied, regional characteristics were reflected and there were distinct characteristics. Shimokawa Town in Hokkaido made the most number of efforts, and after 2008 the number of efforts was increasing; however, along with each of the other examples, the use and application of forest timber offcuts is a task for the future. 展开更多
关键词 Woody biomass biomass town renewable energy forest resources woody resources.
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Roles Portrayed by Women: A Content Analysis in Brazilian Television Advertisements
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作者 Claudia Rosa Acevedo Helenita Tamashiro +1 位作者 Jouliana Jordan Nohara Julio Cunha 《Journalism and Mass Communication》 2013年第7期409-421,共13页
The main purpose of this paper was to examine female roles portrayed by advertising. More specifically, the questions that motivated this research project were "What messages about women have been given to society th... The main purpose of this paper was to examine female roles portrayed by advertising. More specifically, the questions that motivated this research project were "What messages about women have been given to society through advertisement?" and "Have these portrayals been changed during the past decades?" The study consisted of a systematic content analysis of Brazilian commercials from 1973 to 2000. The population from which this sample was drawn consisted of Brazilian commercials which got an award in international and national festivals. A probabilistic sample procedure was employed. Ninety five pieces were selected. The categories and operational rules used in the study were developed based on previous research. This study has proposed that female images in advertising are depicted in three different ways: stereotyped, idealized, and plural portrayals. Our results have revealed that some specific images have changed, however, they continued to be stereotyped and idealized. 展开更多
关键词 roles in advertising gender representations mass communication female roles content analysis inmedia
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Analysis of Nitrosamines in Organic Foods
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作者 L. Peykova D. Obreshkova I. Pencheva 《Journal of Chemistry and Chemical Engineering》 2011年第11期1014-1019,共6页
Nitrosamines are classified by IARC as Group 2B carcinogens. Usually they might be present in organic foods as products of reaction between secondary amines and nitrosation system. The aim of the study was to test the... Nitrosamines are classified by IARC as Group 2B carcinogens. Usually they might be present in organic foods as products of reaction between secondary amines and nitrosation system. The aim of the study was to test the concentration of nitrosamines in Bulgarian products. High performance liquid chromatography with UV detector was used for identification and quantitation. A standard solution of N-nitrosodiethanolamine was used as a reference substance and in the validation procedure of samples. The limit of detection of the method was determined to 14× 10^-9 g/mL. The results of the testing showed that analyzed organic foods produced in Bulgaria did not contain nitrosamines above the limit of detection of the method. 展开更多
关键词 HPLC organic foods NITROSAMINES N-nitrosodiethanolamine
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