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Four commercial spruce lignosulfonates representing the most common acidic, neutral, and alkaline sulfite pulping processes and varying significantly in molecular weight characteristics were tested as partial (40 wt %) phenol substitute materials for the manufacture of lignosulfonate‐phenol‐formaldehyde (LPF) resole resins. Similar as recently reported for technical lignins from nonsulfite pulping processes (kraft, soda, organosolv), all lignosulfonates of this study effectuated a faster viscosity gain during resole cooking compared to the lignin‐free reference resin (1000 mPa s after 120 min vs. 250 min to reach 1000 mPa s). Sodium lignosulfonate featuring the lowest weight average molecular weight (Mw 5780 g mol?1) and dispersity (Ð 6.1) turned out to be superior to the other lignosulfonates with regard to curing rate (B‐time; 3:37 min vs. 6:41–9:08 min) and tensile shear strength development under hot pressing (120 °C; TS,max = 5.64 N mm?2 after 8 min) for beech veneer strips glued together with the respective LPF resins. Calcium and magnesium lignosulfonates are less suited with regard to phenol replacement due to the poor performance of the respective LPF adhesives in terms of tensile shear strength (TS,max = 3.29–3.49 N mm?2 after 12 min) most likely caused by considerable amounts of side products formed in the course of formose‐type reactions. Phenolation of the two promising lignosulfonates, that is, sodium and ammonium lignosulfonate, did neither considerably increase the rate of PF network formation during resin cooking and curing nor improve tensile strength development during hot pressing. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45893.  相似文献   
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Due to random behavior of flood events and inaccuracies in measurements, design, analysis, and operation of flood control systems are subjected to several uncertainties. An important aspect in developing stochastic models for evaluating and analyzing more than one uncertainty is the dependence or independence of them. In flood control projects, hydrologic, hydraulic, geotechnical, and economic uncertainties are important considerations. In this paper, a stochastic Monte-Carlo simulation – optimization modeling approach is described for risk-based design of flood control levees (as a common structural flood control measure): considering multiple dependent uncertainties. It has been applied to the Leaf River reach in Hattiesburg, Mississippi for testing and evaluation of modeling results. Unlike a deterministic model that yields just one set of values for system dimensions, the stochastic model solution gives a range of values for each of them. One of the major reasons for limited field application of uncertainty analysis is difficulties in performing the modeling results in real world contexts. For closing the gap between theory and reality, design charts are developed in this study. This helps decision makers in identifying design values with desired and accepted risks.  相似文献   
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Two novel three-dimensional coordination polymers, formulated as {[M2(μ-C4H4O6)2(H2O)] · 3H2O} (M = Mn for 1 and Cd for 2), have been synthesized under hydrothermal reaction condition. Both complexes were characterized by elemental analysis and IR spectroscopy. Their molecular and crystal structures were determined by X-ray crystal structure analysis and their thermal stability by TGA-DTA methods. Compound 1 crystallizes in the monoclinic space group, P21, while compound 2 crystallizes the orthorhombic space group, P212121. The structures are self-assembled from bifunctional tartrate and water molecules. Tartrate ligands in 1 and 2 contribute to both covalent and hydrogen bonds. Polymeric chains of 1 and 2 are composed of M(II) ions bridged by tartrate ions in O,O′ fashion. The asymmetric units of coordination polymers contain two metal centers having different coordination environments.  相似文献   
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While cancer is the leading cause of human''s deaths worldwide, finding an imaging agent which can detect cancer tumours is needed for cancer diagnosis. In the present study, PEG‐citrate dendrimer‐G2 was used as a nano‐carrier of FITC dye and Iohexol to help passive targeting and uptake of both imaging agents in cancer cells/tumour in vitro and in vivo. Dendrimer was synthesisedand the product characterised using LC‐MS, FT‐IR, DLS, ELS, AFM, and 1 HNMR. After FITC loading into dendrimer, MTT was performed to determine the cytotoxicity of formulation on HEK‐293 and MCF‐7 cells. In vitro imaging using dendrimer‐FITC was done via fluorescent microscope thereafter. Moreover, CT imaging using Iohexol was employed to show the targeting nature and ability of the complex to use as imaging agent in vivo. Data yielded in this study corroborate the notion that the promised dendrimer was synthesised properly and had no toxicity along with FITC on normal cell. Furthermore, CT and fluorescent images showed the targeting nature and imaging ability of Iohexol/FITC loaded dendrimer in vitro and in vivo. Overall, results showed promising characteristics of the novel complexes using dendrimer‐G2 both in vitro and in vivo.Inspec keywords: drug delivery systems, cellular biophysics, molecular biophysics, fluorescence, cancer, tumours, drugs, nanomedicine, biomedical materials, dyes, toxicologyOther keywords: imaging agent, cancer tumours, cancer diagnosis, PEG‐citrate dendrimer‐G, FITC dye, cancer cells, FITC loading, vitro imaging, dendrimer‐FITC, CT imaging, targeting nature, promised dendrimer, fluorescent images, imaging ability, Iohexol/FITC  相似文献   
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There is little evidence about whether eggs affect inflammation. The aim of this meta-analysis was to explore the effects of egg consumption on inflammation. A systematic search of online databases (Institute for Scientific Information (ISI), Scopus, Ovid, PubMed, Cochrane) was used to gather clinical trials that assessed the effect of egg consumption on circulating inflammatory biomarkers. Using a random-effects model, pooled weighted mean differences (WMD) and corresponding standard deviations (SD) were calculated. Of the 21 eligible studies found, nine trials were eligible for analysis. Eight trials assessed high-sensitivity C-reactive protein (hs-CRP), four trials assessed interleukin-6 (IL-6), and five trials assessed tumor necrosis factor-alpha (TNF-α). Egg consumption did not affect hs-CRP (WMD 0.24 mg/L; 95% CI: -0.43, 0.90; I2 = 53.8; P = 0.48), IL-6 (WMD 0.20 pg/mL; 95% CI: -0.71, 1.11; I2 = 69.3; P = 0.50), and TNF-α (WMD: -0.38 pg/mL; 95% CI: -0.87, 0.10; I2 = 0.00; P = 0.12) relative to controls. Overall, this meta-analysis revealed that egg consumption had no significant effect on serum biomarkers of inflammation in adults. © 2019 Society of Chemical Industry  相似文献   
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Multi-species biofilms are found in various bacterial habitats and have industrial relevance. These complex bacterial communities have synergetic effects, unlike a single species. Therefore, it is critical to evaluate these complex communities as a whole. Here, the inhibitory effect of single- and dual-species biofilms of Vibrio neocaledinocus sp. and Pseudoalteromonas piscicida for A36 carbon steel corrosion was investigated. The results demonstrated that the synergistic interactions of the monoculture increased the overall biomass production of the dual-species biofilm, but the growth rate was reduced in the presence of the dual-species culture due to a lack of nutrients. Field emission scanning electron microscopy images also confirmed the development of biofilms—they became more homogenized via exposure time in both the mono- and dual-species cultures. The corrosion resistance of A36 carbon steel positively increased because of the dual-species interactions. This reached the highest value after four weeks of exposure. The highest corrosion inhibition efficiency of 99.8% was achieved in the dual-species cultures. Microbial community analysis revealed the high relative abundance of Pseudoalteromonas piscicida during the initial days of exposure, demonstrating the dominant role of this bacterium in the biofilm structure.  相似文献   
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