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1.
Neural Computing and Applications - This study introduces a neural network (NN) adaptive tracking controller-based reinforcement learning (RL) scheme for unknown nonlinear systems. First, an...  相似文献   
2.
It remains a challenge to maintain the antiadhesion properties of superhydrophobic films after exposure to bacterial environments. In this work, superhydrophobic bactericidal polymer films via the simple incorporation of polyvinylpyrrolidone-iodine (PVP-I) or iodine into polytetrafluoroethylene (PTFE) are fabricated to improve their antiadhesive and antibacterial capability. Superhydrophobic iodine-embedded films, polytetrafluoroethylene/polyvinylpyrrolidone-iodine and polytetrafluoroethylene-iodine (PTFE/PVP-I and PTFE-I), show excellent antiadhesive and bactericidal performances even post exposure to bacterial solutions as compared to iodine-free counterparts by controlling the release of iodine. Especially, superhydrophobic PTFE/PVP-I films display a more sustained iodine release profile and significant antibacterial properties against gram-positive (S. aureus, methicillin-resistant S. aureus (MRSA)) and gram-negative (E. coli) bacteria. Such a facile combination of antiseptic agents and superhydrophobic surface could be widely used for antiseptic biomedical applications.  相似文献   
3.
This work has been concerned with the synthesis of the hydrogels of poly (vinyl pyrrolidone) (NVP), poly (hydroxy ethylmethacrylate) (HEMA), and their copolymer under the effect of gamma radiation in the presence of N,N‐methylenebisacryl‐amide (MBAm) as a crosslinking agent. The effect of the different factors that may affect the gelation and yield product, such as solvent composition and irradiation dose, was investigated. The formed hydrogels were characterized in terms of swelling in water and different organic solvents, X‐ray diffraction (XRD), and IR spectroscopic analysis. The sorption capability of these hydrogels towards some commercial basic and acid dyesstuffs was also studied. The results showed that a solvent mixture composed of equal contents of water and methanol is the most suitable to afford the minimum sol fraction and the highest yield product at a minimal irradiation dose of 10 kGy. It was observed that NVP hydrogel displayed the highest swelling in water, alcohols, and dimethyformamide of ~1300% and a lower tendency to swell in nonpolar solvents. The results showed that HEMA hydrogel has a high affinity to absorb basic dyes while NVP has a tendency for acid dyes. Also, the sorption of either the basic or acid dyes by the different hydrogels was found to greatly depend on the concentration of dye in solution and the mass of the used hydrogel. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 3274–3280, 2004  相似文献   
4.
Gas liquid chromatographic analysis of the fatty acid methyl esters from eggs ofDermacentor andersoni Stiles (Ixodidae) revealed the presence of significant quantities (15% total fatty acids) of an unidentified component with a retention time between C18∶3−C22∶0 fatty acids. Smaller amounts of the unidentified component (ca. 5% total fatty acid) also were detected in host rabbit serum. Purified, the unidentified component's methyl ester collected from the tick eggs by preparative gas liquid chromatography was partially identified and characterized by chemical and spectroscopic analyses. The evidence suggests that the unidentified component is a methyl branched C15 tricarboxylic acid containing two vicinal carboxylic acid groups. Biosynthesis of the unidentified component by the tick is under investigation.  相似文献   
5.
Although several studies have examined the relationship between intimate partner violence (IPV) and drug use among women in drug treatment programs, more information is needed to delineate differences, as a function of the specific drug used. Data from a random sample of 416 women attending methadone programs were analyzed to elucidate the differential associations between IPV and use of the following: marijuana only, cocaine only, heroin only, or cocaine and heroin. Prevalence of IPV among this sample far exceeded estimates from the general population. After adjusting for sociodemographic variables, use of cocaine only was significantly associated with an increased likelihood of experiencing IPV compared with no drug use. Similar results were found for women using both cocaine and heroin. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
Adsorption of Co2+ and Ni2+ from aqueous solutions onto titanate nanotubes (TNTs) synthesized by hydrothermal method in single and binary systems was investigated. The prepared TNTs were completely characterized showing very high surface area compared to previous studies (320 m2/g). The high surface area showed very good optimum removal conditions compared with previous studies (60 min contact time, 0.1 g TNTs dose at pH 5 and room temperature) with high adsorption capacity compared with previous studies as well as conventional adsorbent. Langmuir and Freundlich isothermal models were fitted during this study and Dubinin–Kaganer–Radushkevich isotherms showed physisorption with exclusion of ion exchange mechanism. Pseudo first and second-order kinetics were studied showing more fitting to pseudo second-order equation. Binary system and calculation of separation coefficient showed high ability for Co2+ adsorption by TNTs than Ni+2 in binary system.  相似文献   
7.
YBCO textured thick film was prepared by direct periteetic growth method. Microstructure of the film was characterized. Electron backscattered diffraction (EBSD) technique was applied to the film for quantitative texture analysis. The main difficulty in resolving the ori-entation of YBCO pseudo-cubic structure was investigated. Automated orientation mapping was performed on YBCO thick film. Local tex-ture was presented in the form of orientation maps. Misorientation distribution and crystal growth characterization in the YBCO thick film were revealed. Large domains with well-aligned YBCO grains were formed. Each domain presented clear in-plane and out-plane textures.  相似文献   
8.
The study was carried out in four districts, that is, Gujranwala, Gujarat, Narowal and Sialkot of Punjab, Pakistan. The sampling was carried out randomly in different seasons from the water bodies especially from wastewater. Twenty-one species belonging to Euglenophycota were identified using light microscopy and scanning electron microscopy from which 04 species belong to genus Phacus, 02 species belonging to Trachelomonas and Euglena based on light microscopy. It was observed that Euglena was the most diverse genus and it is supposed to be the indicator species of the polluted water. It was observed that E. oblonga was found in maximum pH range, that is, 7.0–11.0. Similarly, E. brevicaudatus was found in maximum EC, that is, 169 ± 1.5 ms/cm these outcomes indicated that for internal examination along with LM, SEM was necessary for correct identification of algal sample up to specie level.  相似文献   
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10.
Water pollution has become the most severe dilemma in the entire world. In this review, we have discussed the advancement in preparation and properties, plus background and challenges regarding polymer-based nanocomposite membranes. Nanofiltration thin film composite membranes have been given tremendous attention over last two decades relative to conventional systems in desalination of sea water, waste water from industries and ultra pure water production etc. In recent years, significant research efforts have been devoted towards the development of high-performance membranes through surface modification of polymers and nanoparticles, nanotubes, etc. to achieve appreciable salt rejection, water flux and antifouling properties.  相似文献   
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