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431.
Photocatalytic degradation of dye C.I. Acid Orange 7 in aqueous solution using TiO2/hydrogel nanocomposite under solar light simulating source was studied. Hydrogel based on chitosan, itaconic and methacrylic acid was modified with colloidal TiO2 nanoparticles synthetized by acidic hydrolysis of TiCl4 and commercial Degussa P25 TiO2 nanoparticles. SEM/EDX analysis confirmed the presence of TiO2 nanoparticles onto/into hydrogel. It was found that both types of photocatalysts efficiently removed the dye from solution, but sorption rates and photodegradation efficiency were higher in the case of colloidal TiO2 nanoparticles. They ensured complete discoloration of dye solution. The efficiency of the reused TiO2/hydrogel nanocomposite showed that photodegradation activity was maintained at satisfactory level after three repeated cycles of illumination. POLYM. COMPOS., 35:806–815, 2014. © 2013 Society of Plastics Engineers  相似文献   
432.
The main objective of this paper is to revisit the operations and planning of an electric power system, and, more specifically, of its transmission system. The intent is to formulate the underlying problems as decision-making problems with specific performance objectives. Once this is done, it becomes possible to identify open research questions on this subject, including their dependence on the overall industry structure.  相似文献   
433.
The recent identification of plasma membrane (Ca2+)-ATPase (PMCA)-Neuroplastin (Np) complexes has renewed attention on cell regulation of cytosolic calcium extrusion, which is of particular relevance in neurons. Here, we tested the hypothesis that PMCA-Neuroplastin complexes exist in specific ganglioside-containing rafts, which could affect calcium homeostasis. We analyzed the abundance of all four PMCA paralogs (PMCA1-4) and Neuroplastin isoforms (Np65 and Np55) in lipid rafts and bulk membrane fractions from GM2/GD2 synthase-deficient mouse brains. In these fractions, we found altered distribution of Np65/Np55 and selected PMCA isoforms, namely PMCA1 and 2. Cell surface staining and confocal microscopy identified GM1 as the main complex ganglioside co-localizing with Neuroplastin in cultured hippocampal neurons. Furthermore, blocking GM1 with a specific antibody resulted in delayed calcium restoration of electrically evoked calcium transients in the soma of hippocampal neurons. The content and composition of all ganglioside species were unchanged in Neuroplastin-deficient mouse brains. Therefore, we conclude that altered composition or disorganization of ganglioside-containing rafts results in changed regulation of calcium signals in neurons. We propose that GM1 could be a key sphingolipid for ensuring proper location of the PMCA-Neuroplastin complexes into rafts in order to participate in the regulation of neuronal calcium homeostasis.  相似文献   
434.
Non-alcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease which is characterized by extremely complex pathogenetic mechanisms and multifactorial etiology. Some of the many pathophysiological mechanisms involved in the development of NAFLD include oxidative stress, impaired mitochondrial metabolism, inflammation, gut microbiota, and interaction between the brain-liver-axis and the regulation of hepatic lipid metabolism. The new therapeutic approaches in the treatment of NAFLD are targeting some of these milestones along the pathophysiological pathway and include drugs like agonists of peroxisome proliferator-activated receptors (PPARs), glucagon-like peptide-1 (GLP-1) agonists, sodium/glucose transport protein 2 (SGLT2) inhibitors, farnesoid X receptor (FXR) agonists, probiotics, and symbiotics. Further efforts in biomedical sciences should focus on the investigation of the relationship between the microbiome, liver metabolism, and response to inflammation, systemic consequences of metabolic syndrome.  相似文献   
435.
In this research study, the applicability of polycaprolactone‐silicon dioxide and polycaprolactone‐zinc oxide coatings used as primers on papers for offset printing, was analysed. Polycaprolactone nanocomposites with different concentrations of nanoparticles were prepared and coated onto three types of papers: uncoated, low‐coated and gloss. The main aim was to analyse the influence of the nanoparticle concentration in primer on the optical and colorimetric properties of cyan and magenta offset printed samples. To further evaluate the applicability of the primers, the tensile strength of primed samples and their surface properties were analysed. Results show that prepared primers are primarily applicable on uncoated and low coated papers. Both nanoparticles in specific concentrations increased gloss values for printed samples on low‐coated paper, and the addition of both types of nanoparticles increased the rub resistance of printed samples. Furthermore, for each type of nanoparticle, the optimal concentration at which the colour deviation on print was minimised could be defined. Adding nanoparticles to primers did not significantly improve mottling on cyan‐printed samples. However, by increasing the concentration of nanoparticles in the primer by up to 1%, the mottling on magenta‐printed samples decreased.  相似文献   
436.
This study is the first histologic evaluation of an injectable biphasic calcium phosphate (IBCP) in humans six months after socket preservation according to the principles of guided bone regeneration. After tooth extraction, the alveolar ridge of 21 patients was augmented with IBCP (maxresorb® inject) in the test group, while 20 patients in the control group received a bovine xenograft (BX) (cerabone®). Six months after augmentation, a reentry procedure was performed to collect biopsies of regenerated bone for qualitative and quantitative histologic analysis. A total of 20 biopsies were taken for analysis. Qualitative histologic analysis showed complete integration of the biomaterial and no inflammatory tissue reaction, indicating the biocompatibility of the bone grafts and the surrounding tissue in both groups. Histomorphometric analysis showed comparable results in terms of newly formed bone (IBCP: 26.47 ± 14.71%, BX: 30.47 ± 16.39%) and residual biomaterial (IBCP: 13.1 ± 14.07%, BX: 17.89 ± 11.81%), with no significant difference found across groups (p > 0.05, Mann—Whitney U test). Statistical significance between groups was found in the result of soft tissue percentage (IBCP: 60.43 ± 12.73%, BX: 51.64 ± 14.63%, p = 0.046, Mann—Whitney U test). To conclude, IBCP and BX showed good osteoconductivity and biocompatibility with comparable new bone formation six months after alveolar ridge preservation.  相似文献   
437.
Lead zirconate titanate (PZT) is a piezoelectric material that can sense or respond to mechanical deformations and can be used in ceramic electro-mechanical systems (C-MEMS). The microstructural, electrical, and piezoelectric characteristics of thick PZT films on low-temperature cofired ceramics (LTCC) and alumina substrates were studied. The PZT composition was prepared with low-melting-point additives in order to decrease the sintering temperature and to be compatible with thick-film technology. The integration of the PZT thick-film materials on ceramic substrates could lead to degradation of the PZT's characteristics due to the interactions between an active PZT layer and a substrate, particularly with glassy LTCC material. To minimize the interactions with LTCC substrates, an intermediate PZT barrier layer was integrated. The value of the piezoelectric coefficient d 33 was found to be up to 120 pC/N on an alumina substrate and approximately 50 on an LTCC substrate. Based on these results, a cantilever-type actuator was designed and fabricated on alumina substrates. Under an applied voltage of 200 V, the maximum tip deflection was about 5 μm.  相似文献   
438.
TiO2, TiO2−x and Ti3O5 thick-film structures on corundum Al2O3 substrates were prepared using screen-printing technology. The screen-printed deposits were sintered up to 1500 °C in oxidising and reducing atmospheres to vary the Ti4+/Ti3+ ratio and consequently water contact angle. The structure of the thick films was studied with an X-ray powder diffractometer (XRD). The microstructural characteristics and the chemical composition were checked with a scanning electron microscope, equipped with an energy-dispersive spectrometer (EDS). The Ti–O films, up to 55 μm thick, exhibited excellent adhesion to the substrate and had uniform grain- and pore-size distributions. Ti3O5 and Al2O3 were found to be compatible phases up to 1500 °C in a reducing atmosphere. However, rutile-type TiO2 and Al2O3 are not compatible compounds at temperatures up to 1400 °C, in either oxidising or reducing atmospheres. TiO2 and TiO2−x form two types of reaction products with Al2O3. These reaction products were found to have various Ti/Al ratios.  相似文献   
439.
Ginger nut biscuits are popular traditional biscuits which contain honey. In order to improve their nutritive profile and functionality, standard formulation based on wheat flour was substituted with buckwheat flour at three levels (30%, 40%, 50%). The quality attributes (chemical composition, microelements, bioactive compounds (total polyphenols, rutin, quercetin), antioxidative potential, textural and sensory properties) were compared to control biscuit (based on wheat flour) and biscuits substituted with rye at the same levels, since rye is used as an ingredient which improves the quality of ginger nut biscuits. Substitution with buckwheat flour resulted in a significant increase (p < 0.05) in protein, Zn, total polyphenols, antioxidative and chelating activity. Total dietary fibre, Cu, Mn and Fe contents also increased but did not exceed those in rye substituted biscuits. Consumption of 100 g of enriched biscuits could contribute to reaching ≈18–22% (buckwheat) and 16–17% (rye) of the estimated daily average total polyphenols intake, respectively. With the contents of rutin and quercetin at 3.96–6.57 mg/100 g d.b. and 0.087–0.214 mg/100 g d.b., respectively, buckwheat substituted biscuits may significantly contribute to total dietary flavonoid intake and meet the demands of preventive nutrition. Buckwheat enriched biscuits were rated higher regarding sensory attributes, softness and fracturability as compared to control but lower compared to rye supplemented biscuits.  相似文献   
440.
A quantitative multi-residue method that includes 13 sulfonamides, trimethoprim and dapsone was developed and validated according to Commission Decision 2002/657/EC for muscle, milk egg and honey samples. For all matrices, the same extraction procedure was used. Samples were extracted with an acetone/dichloromethane mixture and cleaned up on aromatic sulfonic acid (SO3H) SPE cartridges. After elution and concentration steps, analytes were identified and quantified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Data were acquired according to the multiple reaction-monitoring approach (MRM) and analytes were quantified both by the isotope dilution and the matrix-matched approaches calculating the response factors for the scanned product ions. The developed method shows good linearity, specificity, precision (repeatability and within-laboratory reproducibility), and trueness. Estimated CCβ for sulfonamides ranged between 5.6 and 8.2 µg kg?1 for eggs, between 11.1 and 69.9 µg kg?1 for milk, between 64.7 and 87.9 µg kg?1 for muscle, and between 2.7 and 5.3 µg kg?1 for honey. CCβ values for dapsone were 3.1, 0.6, 0.7 and 1.5 µg kg?1 and for trimethoprim were 3.1, 6.7, 81.7 and 3.0 µg kg?1 calculated for eggs, milk, muscle and honey, respectively. Recovery for all matrices was in the range from 89.1% and 109.7%. In matrix effect testing, no significant deviations were found between different samples of muscle and milk; however, a matrix effect was observed when testing different types of honey. The validation results demonstrate that the method is suitable for routine veterinary drug analysis and confirmation of suspect samples.  相似文献   
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