氯乙烯变温吸附装置的研究

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。     

Metallocene QACs: The Incorporation of Ferrocene Moieties into monoQAC and bisQAC Structures

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.     

Design of data feature-driven 1D/2D convolutional neural networks classifier for recycling black plastic wastes through laser spectroscopy

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.     

Development of silver nanoparticles‐loaded calcium alginate beads embedded in gelatin scaffolds for use as wound dressings

Silver nanoparticles (AgNPs)‐loaded calcium alginate beads embedded in gelatin scaffolds were developed to sustain and maintain the release of silver (Ag⁺) ions over an extended time period. The UV irradiation technique was used to reduce Ag⁺ ions in alginate solution to AgNPs. The average sizes of AgNPs ranged between ca 20 and ca 22 nm. The AgNPs‐loaded calcium alginate beads were prepared by electrospraying of a sodium alginate solution containing AgNPs into calcium chloride (CaCl₂) solution. The AgNPs‐loaded calcium alginate beads were then embedded into gelatin scaffolds. The release characteristics of Ag⁺ ions from both the AgNPs‐loaded calcium alginate beads and the AgNPs‐loaded calcium alginate beads embedded in gelatin scaffolds were determined in either deionized water or phosphate buffer solution at 37 °C for 7 days. Moreover, the AgNPs‐loaded calcium alginate beads embedded in gelatin scaffolds were tested for their antibacterial activity and cytotoxicity. © 2014 Society of Chemical Industry     

Interface self‐reinforcing ability and antibacterial effect of natural chitosan modified polyvinyl chloride‐based wood flour composites

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.     

Dual action bactericides: Quaternary ammonium/N‐halamine‐functionalized cellulose fiber

Bi‐functional antibacterial material was prepared by co‐grafting N‐halamine and quaternary ammonium salt monomers from cellulose fiber. The grafted fiber was characterized by Fourier transform infrared spectra, and X‐ray photoelectron spectra. The N‐halamine derived from the precursor 4‐[(acryloxy)methyl]‐4‐ethyl‐2‐oxazolidinone via chlorination treatment and the oxidative chlorine (Cl⁺) leaching behavior were investigated. The antibacterial activities of singly (only QAs‐functionalized or only Cl⁺‐releasing) and dual (QAs‐functionalized and Cl⁺‐releasing) functional cellulose fibers were tested against Gram‐negative Escherichia coli and Gram‐positive Staphylococcus aureus. Compared to singly functionalized formulations, the bi‐functional cellulose fiber exhibited excellent and rapid bactericidal performance against both E. coli and S. aureus. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40070.     

Synthesis and application of an alternative plasticizer Di(2‐Ethylhexyl)‐1,2‐cyclohexane dicarboxylate

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.