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991.
Bingbing Liu Yuanyuan Hou Lin Wang Dedi Liu Shidan Yu Bo Zou Tian Cui Guangtian Zou Agnieszka Iwasiewicz-Wabnig Bertil Sundqvist 《Diamond and Related Materials》2008,17(4-5):620-623
In this paper, C60 nanosheets with polymeric phases have been obtained under various high pressures and high temperatures, including orthorhombic and tetragonal polymeric phases. The structures have been identified and compared with those of nanorods by photoluminescence and Raman spectroscopies. The main fluorescence band shifted from 1.70 eV in the monomeric phase to near infrared in the polymeric phase when pressure and temperature were increased. The difference of photoluminescence and Raman spectra between nanosheets and nanorods samples treated under the same conditions is probably caused by different polymerization degree in these samples because of different shapes. 相似文献
992.
Vincent Barlier Véronique Bounor-Legaré Gisèle Boiteux Joel Davenas Agnieszka Slazak Andrzej Rybak Jaroslaw Jung 《Synthetic Metals》2009,159(5-6):508-512
TiO2:poly(N-vinylcarbazole) (PVK) bulk-heterojunctions (BHJ) have been elaborated from a blend of a TiO2 precursor with the polymer in solution. The TiO2 precursor is hydrolyzed with the surrounding air humidity in thin film. Titanium isopropoxide [Ti(iOPr)4] and Tetrakis (9H-carbazole-9-yl-ethyl-oxy) titanium [Ti(OeCarb)4] were used as TiO2 precursor. Photogeneration quantum yield in BHJ of TiO2:PVK were determined by the surface potential decay (SPD) technique. Photovoltaic effect was studied in ITO/PEDOT:PSS/TiO2:PVK/Al structures. It was found that the photovoltaic performance is strongly dependent on the homogeneity of the blends. The improved dispersion of the TiO2 phase obtained with the precursor bearing a carbazole group allows efficient electron transport and fill factor enhancement of the photovoltaic devices. 相似文献
993.
Katarzyna Szewczyk Wioleta Pietrzak Katarzyna Klimek Magorzata Miazga-Karska Agnieszka Firlej Marek Flisiski Anna Grzywa-Celiska 《International journal of molecular sciences》2021,22(12)
Skin aging is a natural, unavoidable, and complex process caused by oxidative stress. As a consequence, it leads to an increase in the activation of extracellular matrix disruption enzymes and DNA damage. The search for natural sources that inhibit these mechanisms can be a good approach to prevent skin aging. The purpose of our study was to evaluate the composition of flavonoids and phenolic acids in the extracts obtained from the flowers, roots, and leaves of Eutrema japonicum cultivated in Poland. Then, the resultant extracts were subjected to an assessment of antioxidant, anti-collagenase, anti-elastase, anti-hyaluronidase, antibacterial, and cytotoxic properties. It was demonstrated that the extract from the flowers had the highest content of flavonoid glycosides (17.15 mg/g DE). This extract showed the greatest antioxidant, anti-collagenase, anti-elastase, and anti-hyaluronidase activities compared to the other samples. Importantly, the collagenase inhibitory activity of this extract (93.34% ± 0.77%) was better than that of positive control epigallocatechin gallate (88.49% ± 0.45%). An undeniable advantage of this extract was also to possess moderate antibacterial properties and no cytotoxicity towards normal human skin fibroblasts. Our results suggest that extracts from E. japonicum flowers may be considered as a promising antiaging compound for applications in cosmetic formulations. 相似文献
994.
Magdalena Hasik Wincenty Turek Anna Nyczyk Edyta Stochmal Andrzej Bernasik Agnieszka Sniechota Agnieszka Sołtysek 《Catalysis Letters》2009,127(3-4):304-311
Composites of polyaniline (PANI) or polypyrrole (PPy) doped with chloride ions and Pt or Rh particles were prepared by chemical reduction of metal ions conducted in the presence of the polymers. Based on X-ray diffraction studies it was established that the composites contained metal nanoparticles (5–9 in size). However, according to SEM investigations metal particles were agglomerated (40 nm–1.1 μm in size). Redox activity of the composites in the catalytic isopropyl alcohol conversion was ca. ten times higher than the acid–base one. Pt dispersed in polymer matrices showed higher catalytic activity than Rh. PPy doped with chloride ions had a promoting effect on the activity of Pt catalysts. 相似文献
995.
Anita A.
liwiska Agnieszka Biaek Renata Orowska Dariusz Makowski Katarzyna Sykowska-Baranek Agnieszka Pietrosiuk 《International journal of molecular sciences》2021,22(11)
Polyscias filicifolia (Araliaceae) is broadly used in traditional medicine in Southeast Asia due to its antimicrobial, immunomodulating and cytotoxic activities. The main groups of compounds responsible for pharmacological effects are believed to be oleanolic triterpene saponins. However, Polyscias plants demonstrate relatively slow growth in natural conditions, which led to applying a developing sustainable source of plant material via primary (PSE), secondary (DSE) and direct somatic embryogenesis from DSE (TSE). The AFLP and metAFLP genotyping resulted in 1277 markers, amplified by a total of 24 pairs of selective primers. Only 3.13% of the markers were polymorphic. The analysis of variance showed that the PSE and TSE regenerants differed only in terms of root number, while the DSE plantlets differed for all studied morphological characteristics. Further, the chemical analysis revealed that oleanolic acid (439.72 µg/g DW), ursolic acid (111.85 µg/g DW) and hederagenin (19.07 µg/g DW) were determined in TSE regenerants. Our results indicate that direct somatic embryogenesis ensures the production of homogeneous plant material, which can serve as a potential source of triterpene compounds. Plants obtained via somatic embryogenesis could also be reintroduced into the natural environment to protect and preserve its biodiversity. 相似文献
996.
Niobium-containing siliceous-MSU-X mesoporous molecular sieves have been prepared according to an original pathway by the reaction between low-cost niobium species (ammonium trisoxalate complex of niobium (V)), silica precursor (tetraethyl orthosilicate), and biodegradable surfactant in strong acidic, acidic or almost neutral medium. The selective oxidation of several terpenes and terpenoids (geraniol, limonene, α-terpineol) using hydrogen peroxide as an oxidant agent over novel Nb-catalysts is studied in this work. A variety of (Nb)MSU-X and (Ru,Nb)MSU-X materials prepared under different conditions has been employed (supermicroporous/mesoporous molecular sieves) for this purpose. The structure–function relationships in these catalysts are reported. 相似文献
997.
998.
999.
Effect of flaxseed supplementation of dairy cows' forage on physicochemical characteristic of milk and Raclette cheese
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Dimitri Bocquel Raphaël Marquis Michel Dromard Paul‐André Salamin Janine Rey‐Siggen Julien Héritier Agnieszka Kosińska‐Cagnazzo Wilfried Andlauer 《International Journal of Dairy Technology》2016,69(1):129-136
The composition of bovine milk depends on breed, lactation stage, age of cows and dietary factors. The effect of flaxseed supplementation of forage diet on the chemical composition of milk and the physicochemical and sensory characterisation of Raclette cheese were investigated in this study. As a result of diet supplementation, the proportion of saturated fatty acids in milk decreased and the content of α‐linolenic and oleic acids increased. Concerning the cheese samples, the hardness was significantly reduced due to the flaxseed supplementation, which can positively affect the quality of the cheese due to the diminished risk of crack formation. Sensory characteristics of melted Raclette cheese were not affected by the dietary treatments. 相似文献
1000.
Exploring the association of dairy product intake with the fatty acids C15:0 and C17:0 measured from dried blood spots in a multipopulation cohort: Findings from the Food4Me study
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Viviana Albani Carlos Celis‐Morales Cyril F. M. Marsaux Hannah Forster Clare B. O'Donovan Clara Woolhead Anna L. Macready Rosalind Fallaize Santiago Navas‐Carretero Rodrigo San‐Cristobal Silvia Kolossa Christina Mavrogianni Christina P. Lambrinou George Moschonis Magdalena Godlewska Agnieszka Surwio Thomas E. Gundersen Siv E. Kaland Yannis Manios Iwona Traczyk Christian A. Drevon Eileen R. Gibney Marianne C. Walsh J. Alfredo Martinez Wim H. M. Saris Hannelore Daniel Julie A. Lovegrove Michael J. Gibney Ashley J. Adamson John C. Mathers Lorraine Brennan 《Molecular nutrition & food research》2016,60(4):834-845