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61.
Omdeo Kishorrao Gohatre Manoranjan Biswal Smita Mohanty Sanjay K. Nayak 《应用聚合物科学杂志》2021,138(19):50387
The silane treatment on properties of fly ash (FA) and development of its composite using recycled poly(vinyl chloride) (r-PVC) material retrieve from waste wires and cable insulation are investigated in this work. The use of (3-aminopropyl)triethoxysilane was employed as a coupling agent with some other essential additives. The composites sheet was prepared by means of the melt mixing process and go along with the compression molding process. The superior properties on compatibility between silane-modified FA (FA(Si)) and r-PVC were successfully studied using rheological, thermomechanical, morphological, and water absorption analysis. Primary analysis of r-PVC and FA was employed using Fourier transform infrared spectroscopy analysis. The thermal stability of composites was stable up to 187°C. In addition, significant enhancement on tensile strength as well as young's modulus of composite as compared to untreated r-PVC/FA composites. Morphological properties of silane treated FA based composites presented the good distribution and excellent uniformity with higher wettability of FA particles within r-PVC matrix. The water absorption test showed decrease in water absorption with increase silane treatment concentration FA in the r-PVC matrix. It was remarkable to note that silane treated FA can be prepared as a composite using r-PVC matrix with further modified properties. 相似文献
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介绍了采用变温吸附技术对氯乙烯进行干燥脱水的工艺流程及运行效果,阐述了变温吸附装置运行过程中出现的问题及相应的解决方法。 相似文献
64.
Kyle J. Sommers Brian S. Bentley Dr. Robert G. Carden Savannah J. Post Ryan A. Allen Renee C. Kontos Jacob W. Black Prof. William M. Wuest Prof. Kevin P. C. Minbiole 《ChemMedChem》2021,16(3):467-471
Inspired by the incorporation of metallocene functionalities into a variety of bioactive structures, particularly antimicrobial peptides, we endeavored to broaden the structural variety of quaternary ammonium compounds (QACs) by the incorporation of the ferrocene moiety. Accordingly, 23 ferrocene-containing mono- and bisQACs were prepared in high yields and tested for activity against a variety of bacteria, including Gram-negative strains and a panel of clinically isolated MRSA strains. Ferrocene QACs were shown to be effective antiseptics with some displaying single-digit micromolar activity against all bacteria tested, demonstrating yet another step in the expansion of structural variety of antiseptic QACs. 相似文献
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风力机一般放置在恶劣的环境中,其桨距执行器极易出现故障。文中针对一类含有未知但有界干扰和噪声的风力机系统的桨距执行器故障问题,设计了集员未知输入观测器对桨距的执行器故障进行检测并分离。采用气动机理和现代辨识原理建立风力机系统模型,通过优化未知输入观测器设计对系统中的干扰解耦,基于中心对称多胞体估计不考虑故障时残差的区间包络,并将其作为残差估计的上下动态阈值,实现状态估计。在上述基础上提出了利用一组集员未知输入观测器进行故障诊断的策略。仿真结果表明,在实验过程中,文中所设计的集员未知输入观测器准确地诊断出了风力机桨距执行器的3阶和5阶线性系统在发生突变故障和缓慢时变故障的时间和位置,证明了所提故障诊断策略的有效性。 相似文献
67.
In this study, two types of convolutional neural network (CNN) classifiers are designed to handle the problem of classifying black plastic wastes. In particular, the black plastic wastes have the property of absorbing laser light coming from spectrometer. Therefore, the classification of black plastic wastes remains still a challenging problem compared to classifying other colored plastic wastes using existing spectroscopy (i.e., NIR). When it comes the classification problem of black plastic wastes, effective classification techniques by the laser spectroscopy of Fourier Transform-Infrared Radiation (FT-IR) with Attenuated Total Reflectance (ATR) and Raman to analyze the classification problem of black plastic wastes are introduced. Due to the strong ability of extracting spatial features and remarkable performance in image classification, 1D and 2D CNN through data features are designed as classifiers. The technique of chemical peak points selection is considered to reduce data redundancy. Furthermore, through the selection of data features based on the extracted 1D data with peak points is introduced. Experimental results demonstrate that 2DCNN classifier designed with the help of 2D data feature selection as well as 1DCNN classifier shows the best performance compared with other reported methods for classifying black plastic wastes. 相似文献
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69.
Interface self‐reinforcing ability and antibacterial effect of natural chitosan modified polyvinyl chloride‐based wood flour composites 下载免费PDF全文
Natural chitosan (CS) at four different additions (10, 20, 30, and 40 phr) and particle size ranges (100–140, 140–180, 180–220, and over 260 mesh) are selected to improve the interface adhesion as well as endow a novel antibacterial function to wood flour/polyvinyl chloride (WF/PVC) composites. In the present study, we investigate the interface self‐reinforcing ability of CS to composites by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), dynamic mechanical analysis (DMA), mechanical testing instrument, and water absorption behavior test (WB). The antibacterial activity is also estimated by the method of membrane covering test (MCT) using Escherichia coli. The results recorded show that adding 30 phr CS with the particle size of over 260 mesh is considered to be perfect selection to prepare the excellent interfacial self‐reinforcing and antibacterial WF/PVC/CS composites. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39854. 相似文献
70.
Synthesis and application of an alternative plasticizer Di(2‐Ethylhexyl)‐1,2‐cyclohexane dicarboxylate 下载免费PDF全文
Cyclohexane dicarboxylic acid esters are environmentally friendly and non‐toxic plasticizers, and have similar performance with phthalates which have potential toxicity to human health. In this article, di(2‐ethylhexyl)‐1,2‐cyclohexane dicarboxylate (DEHCH) was synthesized via esterification between hexahydrophthalic anhydride (HHPA) with iso‐octanol by using concentrated sulfuric acid as a catalyst. The effects of reaction parameters on esterification were studied by investigating the temperature, reaction time, molar ratio of iso‐octanol‐to‐HHPA, and catalyst content. Conversions of HHPA to esters were determined. Functional group analysis was conducted by using FTIR and 1H‐NMR spectroscopy. PVC compounds after addition of the synthesized plasticizer DEHCH presented similar plasticizing performance with DEHP and DINCH, as demonstrated by comparisons of the results of mechanical properties, transparency, and volatilization and migration tests obtained for plasticized PVC compounds. DEHCH can also be considered as an alternative plasticizer for DEHP. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39763. 相似文献