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Classification and Extraction of Urban Land-Use Information from High-Resolution Image Based on Object Multi-features 被引量:7
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作者 孔春芳 徐凯 吴冲龙 《Journal of China University of Geosciences》 SCIE CSCD 2006年第2期151-157,共7页
Urban land provides a suitable location for various economic activities which affect the development of surrounding areas. With rapid industrialization and urbanization, the contradictions in land-use become more noti... Urban land provides a suitable location for various economic activities which affect the development of surrounding areas. With rapid industrialization and urbanization, the contradictions in land-use become more noticeable. Urban administrators and decision-makers seek modern methods and technology to provide information support for urban growth. Recently, with the fast development of high-resolution sensor technology, more relevant data can be obtained, which is an advantage in studying the sustainable development of urban land-use. However, these data are only information sources and are a mixture of "information" and "noise". Processing, analysis and information extraction from remote sensing data is necessary to provide useful information. This paper extracts urban land-use information from a high-resolution image by using the multi-feature information of the image objects, and adopts an object-oriented image analysis approach and multi-scale image segmentation technology. A classification and extraction model is set up based on the multi-features of the image objects, in order to contribute to information for reasonable planning and effective management. This new image analysis approach offers a satisfactory solution for extracting information quickly and efficiently. 展开更多
关键词 urban land-use multi-features OBJECT-ORIENTED SEGMENTATION CLASSIFICATION extraction.
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混频输入下基于MF-LSTM的电气设备故障诊断方法
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作者 梁英杰 韩玥莹 +2 位作者 张俊 张天傲 高天露 《海军工程大学学报》 CAS 北大核心 2024年第4期22-27,共6页
针对多型传感器采样频率不统一,现有机器学习算法难以有效处理混频数据输入,无法充分挖掘混频信号中的设备故障特征的问题,首先提出一种混频数据输入下的长短时记忆网络(multi-frequency long and short term memory network,MF-LSTM)架... 针对多型传感器采样频率不统一,现有机器学习算法难以有效处理混频数据输入,无法充分挖掘混频信号中的设备故障特征的问题,首先提出一种混频数据输入下的长短时记忆网络(multi-frequency long and short term memory network,MF-LSTM)架构;然后,对不同采样频率的状态数据分别进行特征提取并进行特征融合,实现混频数据输入下的电气设备的故障诊断任务;最后,利用凯斯西储大学轴承数据集对所提模型进行了算例验证,结果表明:相比于单频信号输入,混频输入平均提高故障诊断精度1.72%。该实验结果证明了所提出的基于MF-LSTM的故障诊断框架的有效性和混频数据输入的必要性。 展开更多
关键词 电气设备 故障诊断 状态数据 特征提取 mf-LSTM
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Radar false alarm plots elimination based on multi-feature extraction and classification
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作者 Cheng Yi Zhao Yan Yin Peiwen 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2024年第1期83-92,共10页
Caused by the environment clutter,the radar false alarm plots are unavoidable.Suppressing false alarm points has always been a key issue in Radar plots procession.In this paper,a radar false alarm plots elimination me... Caused by the environment clutter,the radar false alarm plots are unavoidable.Suppressing false alarm points has always been a key issue in Radar plots procession.In this paper,a radar false alarm plots elimination method based on multi-feature extraction and classification is proposed to effectively eliminate false alarm plots.Firstly,the density based spatial clustering of applications with noise(DBSCAN)algorithm is used to cluster the radar echo data processed by constant false-alarm rate(CFAR).The multi-features including the scale features,time domain features and transform domain features are extracted.Secondly,a feature evaluation method combining pearson correlation coefficient(PCC)and entropy weight method(EWM)is proposed to evaluate interrelation among features,effective feature combination sets are selected as inputs of the classifier.Finally,False alarm plots classified as clutters are eliminated.The experimental results show that proposed method can eliminate about 90%false alarm plots with less target loss rate. 展开更多
关键词 radar plots elimination density based spatial clustering of applications with noise multi-feature extraction CLASSIFIER
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基于VMD和MF-DFA的往复压缩机气阀故障特征提取方法 被引量:4
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作者 王金东 李颖 +2 位作者 赵海洋 欧凌非 夏法锋 《化工自动化及仪表》 CAS 2018年第6期458-463,共6页
针对往复压缩机气阀故障振动信号在进行多重分形分析时易受时间序列非平稳趋势影响,无法准确揭示其多重分形特征的难题,提出了基于变分模态分解(Variational Mode Decomposition,VMD)和多重分形去趋势分解(Multifractal Detrended Fluct... 针对往复压缩机气阀故障振动信号在进行多重分形分析时易受时间序列非平稳趋势影响,无法准确揭示其多重分形特征的难题,提出了基于变分模态分解(Variational Mode Decomposition,VMD)和多重分形去趋势分解(Multifractal Detrended Fluctuation Analysis,MF-DFA)的往复压缩机气阀故障特征提取方法。首先,利用VMD方法对往复压缩机气阀信号进行分解,根据互相关系数法选取模态分量进行信号重构,可有效消除噪声干扰;然后采取MF-DFA方法对重构后信号进行分析,以反映结构特征和局部振动信号尺度行为的特征向量参数Δα、α(fmax)、fmax、Δf和B为模式识别向量,极限学习机(Extreme Learning Machine,ELM)为故障分类器对往复压缩机气阀的4种状态进行分类识别。研究结果表明:该方法能够揭示往复压缩机气阀振动信号的多重分形特性,具有较强的辨识能力。 展开更多
关键词 往复压缩机 气阀 故障诊断 特征提取 VMD mf-DFA ELM
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MF-DFA方法的船舶辐射噪声特征提取
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作者 李瑜 章新华 于亚静 《火力与指挥控制》 CSCD 北大核心 2007年第12期46-48,共3页
分析船舶辐射噪声和环境噪声的多重分形特征的成因,提出利用MF-DFA方法对实测船舶辐射噪声进行处理,将环境噪声的分形特征削弱或消除,从而只得到船舶辐射噪声的分形特征,再结合MF-DFA方法与盒子维的定义进行船舶辐射噪声进行特征提取。
关键词 多重分形特征 特征提取 趋势消除 mf-DFA方法
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气相色谱-质谱法测定分散剂MF中喹啉的质量分数 被引量:4
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作者 张云 张薇 +3 位作者 叶琼 寿谦益 董岳龙 鲍国芳 《印染助剂》 CAS 北大核心 2018年第6期59-61,64,共4页
建立了测定分散剂MF中喹啉质量分数的气相色谱-质谱法。以二甲苯为萃取溶剂,固相萃取法进行前处理,内标法定量。喹啉为0.5~50μg/m L时呈线性关系,相关系数为0.999 9,方法检出限为0.3μg/m L,加标回收率为70%~130%,RSD小于5%,该方法线... 建立了测定分散剂MF中喹啉质量分数的气相色谱-质谱法。以二甲苯为萃取溶剂,固相萃取法进行前处理,内标法定量。喹啉为0.5~50μg/m L时呈线性关系,相关系数为0.999 9,方法检出限为0.3μg/m L,加标回收率为70%~130%,RSD小于5%,该方法线性关系良好,检出限低,回收率高,精密度好,适用于分散剂MF中喹啉质量分数的检测。 展开更多
关键词 分散剂mf 喹啉 固相萃取 内标法 气相色谱-质谱法
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基于三角覆盖MF-DFA的环形零件图像种类特征研究
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作者 盛文婷 王幸 +1 位作者 赖科学 何涛 《电子设计工程》 2021年第21期1-7,共7页
针对多重分形去趋势波动分析(Multifractality Detrended Fluctuation Analysis,MF-DFA)可以从全局和局部两方面出发,深层次发掘目标物体的各种特征,但存在过度覆盖的缺点,提出一种能够减少过度覆盖的三角覆盖MF-DFA,用于环形零件图像... 针对多重分形去趋势波动分析(Multifractality Detrended Fluctuation Analysis,MF-DFA)可以从全局和局部两方面出发,深层次发掘目标物体的各种特征,但存在过度覆盖的缺点,提出一种能够减少过度覆盖的三角覆盖MF-DFA,用于环形零件图像的种类特征提取。选用齿环、齿轮、轴承与螺母这四类常见环形零件的图像为研究对象,利用三角覆盖MF-DFA研究环形零件图像的种类特征,结合核化主成分分析(Kernelized Principal Component Analysis,KPCA)获得特征值。使用支持向量机(Support Vector Machines,SVM)对特征值进行识别验证,其识别正确率达99.5%,证实该方法可以准确提取环形零件图像的种类特征。 展开更多
关键词 三角覆盖mf-DFA 环形零件图像 种类特征提取 KPCA SVM
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基于错误纠正模块的场景文本识别算法
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作者 于洁潇 张大壮 何凯 《天津大学学报(自然科学与工程技术版)》 EI CAS CSCD 北大核心 2023年第4期400-407,共8页
近年来,场景文本识别技术得到了飞速发展.然而,由于不规则场景文本图像中经常存在诸如杂物遮挡、分布扭曲、光照不足等视觉障碍,使得现有方法不能对单词中某些字符进行准确识别,进而产生较多的错误识别.为了解决这一问题,本文提出了一... 近年来,场景文本识别技术得到了飞速发展.然而,由于不规则场景文本图像中经常存在诸如杂物遮挡、分布扭曲、光照不足等视觉障碍,使得现有方法不能对单词中某些字符进行准确识别,进而产生较多的错误识别.为了解决这一问题,本文提出了一种基于错误纠正(error correction,EC)模块的场景文本识别算法.与现有算法中的纠错模块不同,所提出的EC模块是一个序列到序列的预测模型.在EC模块的编解码结构中增加了多单元注意力机制,能够更加关注特征图中的一些重要信息.EC模块可直接从纯文本中学习语义信息,用于纠正拼写错误的文本.此外,提出了一种基于场景文本识别的多特征(multi-feature,MF)提取器,该提取器由5个MF单元组成,可分别从Resnet-45后5个模块的输出中提取特征信息.与传统的方法相比,MF提取器可以从不同深度挖掘更加丰富的图像信息.在7个数据集上的对比实验结果表明,与当前先进方法相比,所提算法在性能上具有明显的优势. 展开更多
关键词 场景文本识别 语义信息纠错 多特征提取 深度学习
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白姑鱼和小黄鱼肉中挥发性风味物质的鉴定 被引量:35
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作者 张晶晶 王锡昌 施文正 《食品科学》 EI CAS CSCD 北大核心 2019年第14期206-213,共8页
采用新型固相萃取整体捕集剂(Mono-Trap)结合气相色谱-质谱-嗅闻技术对白姑鱼和小黄鱼肉的挥发性风味物质进行鉴定,分别得到42种和49种挥发性成分。进一步通过芳香萃取物稀释分析法分别从白姑鱼和小黄鱼肉挥发物中筛选出12种和6种挥发物... 采用新型固相萃取整体捕集剂(Mono-Trap)结合气相色谱-质谱-嗅闻技术对白姑鱼和小黄鱼肉的挥发性风味物质进行鉴定,分别得到42种和49种挥发性成分。进一步通过芳香萃取物稀释分析法分别从白姑鱼和小黄鱼肉挥发物中筛选出12种和6种挥发物,其中9种挥发物经质谱和线性保留指数鉴定。进一步结合校准频率(modified frequency,MF)法,各筛选出2种鱼肉中排名前10的气味物质。白姑鱼中香气稀释(flavor dilution,FD)因子最高为40的化合物为三甲胺、2-辛烯-1-醇、壬醛及金属味未知化合物。结合MF排名,得到三甲胺和2-辛烯-1-醇对白姑鱼贡献较大;小黄鱼中FD因子最高为40的化合物为己醛和2-辛烯-1-醇,但结合MF排名,对其气味贡献较大的是三甲胺和未知烧烤味化合物。6-甲基-5-庚烯-2-酮为2种鱼中均鉴定出的一种带金属味或血腥味成分,根据MF排名,该化合物对白姑鱼影响更大。2,3-戊二酮、1-戊烯-3-醇为小黄鱼中MF较靠前的物质,结合三甲胺和未知烧烤味化合物以及白姑鱼中未鉴定到的二甲基二硫醚,这些挥发物可能是造成其与白姑鱼气味感知差异的原因。 展开更多
关键词 白姑鱼 小黄鱼 挥发性风味 气相色谱-嗅辨仪 香气萃取稀释分析 校准频率法
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色谱指纹图谱全定性相似度和全定量相似度质控体系研究 被引量:61
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作者 孙国祥 宋杨 +1 位作者 毕雨萌 智雪枝 《中南药学》 CAS 2007年第3期263-267,共5页
目的对中药色谱指纹图谱的全定性相似度和全定量相似度质控体系进行研究。方法用银杏叶提取物的HPLC指纹图谱实验结果为例,分别从化学成分分布相似性和含量相似性2个方面评价不同批次银杏叶提取物与对照指纹图谱的相似程度。提出用SF和S... 目的对中药色谱指纹图谱的全定性相似度和全定量相似度质控体系进行研究。方法用银杏叶提取物的HPLC指纹图谱实验结果为例,分别从化学成分分布相似性和含量相似性2个方面评价不同批次银杏叶提取物与对照指纹图谱的相似程度。提出用SF和S′F构成全定性相似度法来准确地解决色谱指纹图谱的定性评价问题;用W%与R%,C%与P%,Q%与M%,以及QF%与MF%分别构成第一、第二、第三、第四级全定量相似度。评价时,全定性相似度均〉0.9为必要条件,上述4种全定量相似度可选择任意1组,制剂控制在90%-110%,原料控制在85%-120%,组内相差不得超过10%为合格。结果当全定性相似度和全定量相似度合格时,一方面可保证削减大指纹峰影响,等权对待小指纹峰贡献;另一方面,从突出大指纹峰对体系的作用出发进行评价,这样能同时兼顾检测所有指纹峰对体系的定性定量的贡献作用。结论全定性相似度和全定量相似度的密切结合构成色谱指纹图谱新的质控体系,是利用色谱指纹图谱宏观控制中药质量的最佳方法。 展开更多
关键词 全定性相似度(SF和S′F) 全定量相似度(W%与R% C%与P% Q%与M% 以及QF%与mf%) 银杏叶提取物 HPLC指纹图谱
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Diagnosis of sewer pipe defects on image recognition of multi-features and support vector machine in a southern Chinese city 被引量:5
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作者 Xiangyang Ye Jian’e Zuo +4 位作者 Ruohan Li Yajiao Wang Lili Gan Zhonghan Yu Xiaoqing Hu 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2019年第2期29-41,共13页
Closed circuit television(CCTV)systems are widely used to inspect sewer pipe conditions.During the diagnosis process,the manual diagnosis of defects is time consuming,labor intensive and error prone.To assist inspecto... Closed circuit television(CCTV)systems are widely used to inspect sewer pipe conditions.During the diagnosis process,the manual diagnosis of defects is time consuming,labor intensive and error prone.To assist inspectors in diagnosing sewer pipe defects on CCTV inspection images,this paper presents an image recognition algorithm that applies features extraction and machine learning approaches.An algorithm of image recognition techniques,including Hu invariant moment,texture features,lateral Fourier transform and Daubechies(DBn)wavelet transform,was used to describe the features of defects,and support vector machines were used to classify sewer pipe defects.According to the inspection results,seven defects were defined;the diagnostic system was applied to a sewer pipe system in a southern city of China,and 28,760 m of sewer pipes were inspected.The results revealed that the classification accuracies of the different defects ranged from 51.6% to 99.3%.The overall accuracy reached 84.1%.The diagnosing accuracy depended on the number of the training samples,and four fitting curves were applied to fit the data.According to this paper,the logarithmic fitting curve presents the highest coefficient of determination of 0.882,and more than 200 images need to be used for training samples to guarantee the accuracy higher than 85%. 展开更多
关键词 SEWER PIPE DEFECTS DEFECT diagnosing Image recognition multi-features extraction Support vector machine
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Recognition of weeds at asparagus fields using multi-feature fusion and backpropagation neural network 被引量:1
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作者 Yafei Wang Xiaodong Zhang +3 位作者 Guoxin Ma Xiaoxue Du Naila Shaheen Hanping Mao 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2021年第4期190-198,共9页
In order to solve the problem of low recognition rates of weeds by a single feature,a method was proposed in this study to identify weeds in Asparagus(Asparagus officinalis L.)field using multi-feature fusion and back... In order to solve the problem of low recognition rates of weeds by a single feature,a method was proposed in this study to identify weeds in Asparagus(Asparagus officinalis L.)field using multi-feature fusion and backpropagation neural network(BPNN).A total of 382 images of weeds competing with asparagus growth were collected,including 135 of Cirsium arvense(L.)Scop.,138 of Conyza sumatrensis(Retz.)E.Walker,and 109 of Calystegia hederacea Wall.The grayscale images were extracted from the RGB images of weeds using the 2G-R-B factor.Threshold segmentation of the grayscale image of weeds was applied using Otsu method.Then the internal holes of the leaves were filled through the expansion and corrosion morphological operations,and other interference targets were removed to obtain the binary image.The foreground image was obtained by masking the binary image and the RGB image.Then,the color moment algorithm was used to extract weeds color feature,the gray level co-occurrence matrix and the Local Binary Pattern(LBP)algorithm was used to extract weeds texture features,and seven Hu invariant moment features and the roundness and slenderness ratio of weeds were extracted as their shape features.According to the shape,color,texture,and fusion features of the test samples,a weed identification model was built.The test results showed that the recognition rate of Cirsium arvense(L.)Scop.,Calystegia hederacea Wall.and Conyza sumatrensis(Retz.)E.Walker were 82.72%(color feature),72.41%(shape feature),86.73%(texture feature)and 93.51%(fusion feature),respectively.Therefore,this method can provide a reference for the study of weeds identification in the asparagus field. 展开更多
关键词 weeds recognition image processing feature extraction multi-feature fusion BP neural network asparagus field
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Deep Optimal VGG16 Based COVID-19 Diagnosis Model
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作者 M.Buvana K.Muthumayil +3 位作者 S.Senthil kumar Jamel Nebhen Sultan S.Alshamrani Ihsan Ali 《Computers, Materials & Continua》 SCIE EI 2022年第1期43-58,共16页
Coronavirus(COVID-19)outbreak was first identified in Wuhan,China in December 2019.It was tagged as a pandemic soon by the WHO being a serious public medical conditionworldwide.In spite of the fact that the virus can ... Coronavirus(COVID-19)outbreak was first identified in Wuhan,China in December 2019.It was tagged as a pandemic soon by the WHO being a serious public medical conditionworldwide.In spite of the fact that the virus can be diagnosed by qRT-PCR,COVID-19 patients who are affected with pneumonia and other severe complications can only be diagnosed with the help of Chest X-Ray(CXR)and Computed Tomography(CT)images.In this paper,the researchers propose to detect the presence of COVID-19 through images using Best deep learning model with various features.Impressive features like Speeded-Up Robust Features(SURF),Features from Accelerated Segment Test(FAST)and Scale-Invariant Feature Transform(SIFT)are used in the test images to detect the presence of virus.The optimal features are extracted from the images utilizing DeVGGCovNet(Deep optimal VGG16)model through optimal learning rate.This task is accomplished by exceptional mating conduct of Black Widow spiders.In this strategy,cannibalism is incorporated.During this phase,fitness outcomes are rejected and are not satisfied by the proposed model.The results acquired from real case analysis demonstrate the viability of DeVGGCovNet technique in settling true issues using obscure and testing spaces.VGG16 model identifies the imagewhich has a place with which it is dependent on the distinctions in images.The impact of the distinctions on labels during training stage is studied and predicted for test images.The proposed model was compared with existing state-of-the-art models and the results from the proposed model for disarray grid estimates like Sen,Spec,Accuracy and F1 score were promising. 展开更多
关键词 COVID 19 multi-feature extraction vgg16 optimal learning rate
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Research on Feature Fusion Technology of Fruit and Vegetable Image Recognition Based on SVM
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作者 Yanqing Wang Yipu Wang +1 位作者 Chaoxia Shi Hui Shi 《国际计算机前沿大会会议论文集》 2016年第1期150-152,共3页
In order to improve the accuracy and stability of fruit and vegetable image recognition by single feature, this project proposed multi-feature fusion algorithms and SVM classification algorithms. This project not only... In order to improve the accuracy and stability of fruit and vegetable image recognition by single feature, this project proposed multi-feature fusion algorithms and SVM classification algorithms. This project not only introduces the Reproducing Kernel Hilbert space to improve the multi-feature compatibility and improve multi-feature fusion algorithm, but also introduces TPS transformation model in SVM classifier to improve the classification accuracy, real-time and robustness of integration feature. By using multi-feature fusion algorithms and SVM classification algorithms, experimental results show that we can recognize the common fruit and vegetable images efficiently and accurately. 展开更多
关键词 FEATURE extraction multi-feature FUSION Support VECTOR MACHINE FRUIT and VEGETABLE image recognition
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T酸反萃液混合甲基萘磺化物制备分散剂MF的新工艺
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作者 陈伟兴 张争争 +3 位作者 章文刚 李家琪 章小芳 陶彬彬 《染料与染色》 CAS 2020年第3期32-34,共3页
介绍了一种制备分散剂MF的新工艺。在少量硫酸底酸存在条件下,用液体三氧化硫作磺化剂对甲基萘进行磺化。反应后的磺化料中加入T酸反萃液,经水解、甲醛缩合、中和、除甲醛后得到分散剂MF。结果显示,甲基萘经SO3磺化后,当加入与甲基萘质... 介绍了一种制备分散剂MF的新工艺。在少量硫酸底酸存在条件下,用液体三氧化硫作磺化剂对甲基萘进行磺化。反应后的磺化料中加入T酸反萃液,经水解、甲醛缩合、中和、除甲醛后得到分散剂MF。结果显示,甲基萘经SO3磺化后,当加入与甲基萘质量比1∶2的T酸反萃液、缩合时甲醛(折百)与甲基萘质量比1∶6.5、反应温度110±5℃、反应时间4 h、压力0.15~0.20 MPa时,可以得到质量合格的分散剂MF,该工艺实现了废水再利用。 展开更多
关键词 T酸反萃液 磺化料 废水利用 分散剂mf
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