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181.
CO2 gas barrier properties in polymer nanocomposite coatings containing Li‐hectorite clays
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This is a study of the addition of hydrophilic Li‐hectorite nanoplatelets in waterborne acrylic resin emulsions and the resulting nanocomposite coatings. The mechanism of the dispersion of the nanoplatelets during film formation and curing from aqueous suspensions is described. The morphological features of the coating and the state of delamination is examined via X‐ray diffraction for three different clay treatment procedures. The influence of the shape of the nanosized objects and their dispersion level on the transport characteristics of the nanocomposite film are measured and their effect on the polymer free volume is discussed. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40805. 相似文献
182.
Alexandros D. Bantias Ioannis A. Tegos Theodoros A. Chrysanidis Asimina M. Athanatopoulou 《土木工程与建筑:英文版》2014,(7):833-845
It is known that the slabs on soil constitute one of the most difficult types of structures despite their apparent simplicity. The objective of this paper is to give a general survey of the design of ground supported slabs with the interposition of a suitable subbase. A solution is proposed with the following characteristics: (1) complete suppression of joints; (2) conventional reinforcement with meshes in the upper and lower fiber of the slab in order to confront and distribute cracking that is caused by hindrance of free contractions and expansions; (3) effective confrontation of problems of bulging. The proposal is in effect on one hand for industrial floorings and on the other hand for concrete pavings with large durability requirement. 相似文献
183.
Emerging applications introduce the requirement for novel association-rule mining algorithms that will be scalable not only with respect to the number of records (number of rows) but also with respect to the domain's size (number of columns). In this paper, we focus on the cases where the items of a large domain correlate with each other in a way that small worlds are formed, that is, the domain is clustered into groups with a large number of intra-group and a small number of inter-group correlations. This property appears in several real-world cases, e.g., in bioinformatics, e-commerce applications, and bibliographic analysis, and can help to significantly prune the search space so as to perform efficient association-rule mining. We develop an algorithm that partitions the domain of items according to their correlations and we describe a mining algorithm that carefully combines partitions to improve the efficiency. Our experiments show the superiority of the proposed method against existing algorithms, and that it overcomes the problems (e.g., increase in CPU cost and possible I/O thrashing) caused by existing algorithms due to the combination of a large domain and a large number of records. 相似文献
184.
Kalva Hari Chang Shih-Fu Eleftheriadis Alexandros 《Multimedia Tools and Applications》1997,5(2):119-132
To promote the development and deployment of broadband audio visual services, DAVIC has been working on specifying the standards and interfaces for end-to-end systems providing services to consumers over broadband networks. DAVIC specifies tools to provide these broadband services. Since the tools specified by DAVIC are standardized/developed by independent organizations, it is important to verify that the complete system works when these tools are used together. An interoperability event was organized by Columbia University for this very purpose. In this paper we first introduce DAVIC and DAVIC systems and then give details of the interoperability event: the motivation, goals, and results. 相似文献
185.
The more the design of buildings becomes bioclimatically conscious, the more the behaviour of these buildings tends to become skin dominated. Double elements, much like the different layers of the skin of animals or human beings, can serve more than one purpose at the same time, such as shading, movement of air, evaporation, filtering of light or the support of other elements. Their use can help in a better integration of indoor and outdoor space, an extension of functions and a smoother transition from a more to a less controlled environment. 相似文献
186.
187.
Various 2,5- and 1,4-substituted and unsubstituted myo-inositol tetrakisphosphates and bispyrophosphates were prepared following a general synthetic pathway. All final compounds were tested for their capability to induce oxygen release from human hemoglobin. Most of these proved to be efficient allosteric effectors, with similar affinities for hemoglobin to that of myo-inositol hexakisphosphate, which is one of the best known allosteric effectors of hemoglobin. The efficacy was found to be higher for free phosphates than pyrophosphates. As allosteric Hb effectors, these compounds enable enhanced oxygen release. These effects increase with the strength of Hb binding and correspond primarily to electrostatic interactions. Stereochemical and steric factors also play a significant but secondary role in molecular recognition. In view of the central role played by hypoxia in numerous types of diseases, the exploration of myo-inositol phosphate derivatives represents an important avenue in the search for substances which act on the oxygenation status of tissues and may have significant potential in the discovery and development of novel drug candidates. 相似文献
188.
Gazi IF Apostolou FA Liberopoulos EN Filippatos TD Tellis CC Elisaf MS Tselepis AD 《Lipids》2011,46(10):953-960
The objective of the present study was to evaluate the effects of acute infection with Leptospira interrogans on lipids, lipoproteins and associated enzymes. Fasting serum levels of total cholesterol (TC), low-density lipoprotein cholesterol
(LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), apolipoproteins (apo) A-Ι, B, E, C-II, C-III and
lipoprotein (a) [Lp(a)] were determined in patients with Leptospirosis on diagnosis and 4 months after recovery as well as
in age- and sex-matched controls. Activities of cholesteryl-ester transfer protein (CETP) and lipoprotein-associated phospholipase
A2 (Lp-PLA2) as well as paraoxonase 1 (PON1) hydrolysing activity and levels of cytokines were determined. LDL subclass analysis was
performed with Lipoprint LDL System. Eleven patients (10 men, mean age 49.5 ± 8.4 years) and 11 controls were included. TC,
HDL-C, LDL-C, apoA-I, apoB and Lp(a) levels were lower at baseline, whereas TG and apoE levels were elevated compared with
4 months later. At baseline, higher levels of cytokines and cholesterol concentration of small dense LDL particles (sdLDL-C)
were noticed, whereas LDL particle size was lower compared with follow-up. Activities of plasma Lp-PLA2 and HDL-associated Lp-PLA2 were lower at baseline compared with post treatment values, whereas PON1 activity was similar at baseline and 4 months later.
4 months after recovery, the levels of all lipid parameters evaluated did not differ compared with controls, except for HDL-C
which remained lower. PON1 activity both at baseline and 4 months later was lower in patients compared with controls. Leptospirosis
is associated with atherogenic changes of lipids, lipoproteins and associated enzymes. 相似文献
189.
Thickened wastewater activated sludge was treated in 13 pilot-scale sludge treatment wetlands of various configurations that operated continuously for three years in North Greece. Sludge was loaded for approximately 2.5 years, and the beds were left to rest for the remaining period. Three different sludge loading rates were used that represented three different population equivalents. Residual sludge stability and maturity were monitored for the last year. Sludge was regularly sampled and microbial respiration activity indices were measured via a static respiration assay. The phytotoxicity of sludge was quantified via a seed germination bioassay. Measurements of total solids, organic matter, total coliforms, pH and electrical conductivity were also made. According to microbial respiration activity measurements, the sludge end-product was classified as stable. The germination index of the final product exceeded 100% in most wetland units, while final pH values were approximately 6.5. The presence of plants positively affected the stability and maturity of the residual sludge end-product. Passive aeration did not significantly affect the quality of the residual sludge, while the addition of chromium at high concentrations hindered the sludge decomposition process. Conclusively, sludge treatment wetlands can be successfully used, not only to dewater, but also to stabilize and mature wastewater sludge after approximately a four-month resting phase. 相似文献