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91.
Carolina Tallon Monika Limacher George V. Franks 《Journal of the European Ceramic Society》2010,30(14):2819-2826
The effect of the nanometric-ranged particle size of the starting powder through a simple and well-established shaping method, slip casting, has been studied. Several alumina suspensions with the same viscosity (but different solid content suspensions) and different particle size (11, 44, 190 and 600 nm) were prepared and shaped into a dense body. The green and sintered densities ranged between 30–67% and 63–99% of the theoretical value, respectively. These values, together with the microstructure observations reveal the effect of the solid content of the suspensions and the characteristics of the ceramic powder, leading to the determination of an optimal particle size. Based on both processability (rheological behaviour) and microstructure (density and grain size) it has been determined that particles with sizes ranging 100–300 nm are the best for preparing concentrated suspensions with low viscosity and bodies with density close to the theoretical value when using conventional pressureless sintering densification. 相似文献
92.
93.
The Impact of Zeta Potential and Physicochemical Properties of TiO2‐Based Nanocomposites on Their Biological Activity 下载免费PDF全文
Agnieszka Maria Jastrzębska Patrycja Kurtycz Andrzej Olszyna Ewa Karwowska Ewa Miaśkiewicz‐Pęska Monika Załęska‐Radziwiłł Nina Doskocz Dariusz Basiak 《International Journal of Applied Ceramic Technology》2015,12(6):1157-1173
The aim of this research was to observe the relationship between zeta potential, morphology, surface area, porosity, chemical composition, and ecotoxicity of nanocomposite powders such as Au/TiO2, Ag2O/TiO2, PdO/TiO2, Ag/TiO2/SiO2, Ag/N(C)TiO2, and SiO2/TiO2 from which Ag2O/TiO2, Ag/N(C)/TiO2, and Ag/TiO2/SiO2 were exhibiting good antimicrobial properties. It was observed, that nanomaterials characterized by similar morphology and zeta potential revealed the similar toxic behavior. The samples of higher agglomeration and higher zeta potential, especially Ag/TiO2/SiO2 xerogel and TiO2/SiO2 aerogel were generally less ecotoxic to water organisms and plants. They were also not genotoxic in concentrations up to 500 and 250 mg/L, respectively. 相似文献
94.
Valery A. Isidorov Sławomir Bakier Ewa Pirożnikow Monika Zambrzycka Izabela Swiecicka 《Journal of chemical ecology》2016,42(6):475-485
Honey bees harvest resins from various plant species and use them in the hive as propolis. While there have been a number of studies concerning the chemical composition of this antimicrobial product, little is known about selective behavior and bee preference when different potential plant sources of resin are available. The main objective of this paper was to investigate some aspects of behavioral patterns of honeybees in the context of resin acquisition. Samples of propolis originating from temperate zones of Europe and the supposed botanical precursors of the product were analyzed. Taxonomical markers of bud resins of two white birch species, aspen, black poplar, horse-chestnut, black alder, and Scots pine were determined through GC-MS analysis. All these trees have been reported as sources of propolis, but comparisons of the chemical composition of their bud resins with the compositions of propolis samples from seven European countries have demonstrated the presence of taxonomical markers only from black poplar, aspen, and one species of birch. This suggests selective behavior during the collection of bud resins by honeybees. To examine the causes of such selectivity, the antimicrobial properties of bud resins were determined. Horse-chestnut resins had lower antimicrobial activity than the other resins which did not differ significantly. 相似文献
95.
Monika Kova
evi Dora Markulin Matea Zelenika Marko Marjanovi Marija Lovri Denis Polan
ec Marina Ivan
i Jasna Mrv
i Kreimir Mol
anov Valentina Milainovi Sun
ica Roca Ivan Kodrin Lidija Barii 《International journal of molecular sciences》2022,23(20)
Considering the enormous importance of protein turns as participants in various biological events, such as protein–protein interactions, great efforts have been made to develop their conformationally and proteolytically stable mimetics. Ferrocene-1,1′-diamine was previously shown to nucleate the stable turn structures in peptides prepared by conjugation with Ala (III) and Ala–Pro (VI). Here, we prepared the homochiral conjugates of ferrocene-1,1′-diamine with l-/d-Phe (32/35), l-/d-Val (33/36), and l-/d-Leu (34/37) to investigate (1) whether the organometallic template induces the turn structure upon conjugation with amino acids, and (2) whether the bulky or branched side chains of Phe, Val, and Leu affect hydrogen bonding. Detailed spectroscopic (IR, NMR, CD), X-ray, and DFT studies revealed the presence of two simultaneous 10-membered interstrand hydrogen bonds, i.e., two simultaneous β-turns in goal compounds. A preliminary biological evaluation of d-Leu conjugate 37 showed its modest potential to induce cell cycle arrest in the G0/G1 phase in the HeLa cell line but these results need further investigation. 相似文献
96.
Agata Winiarska Monika Knysak Katarzyna Nabrdalik Janusz Gumprecht Tomasz Stompr 《International journal of molecular sciences》2021,22(19)
The incidence of type 2 diabetes (T2D) has been increasing worldwide, and diabetic kidney disease (DKD) remains one of the leading long-term complications of T2D. Several lines of evidence indicate that glucose-lowering agents prevent the onset and progression of DKD in its early stages but are of limited efficacy in later stages of DKD. However, sodium-glucose cotransporter-2 inhibitors (SGLT2i) and glucagon-like peptide-1 receptor (GLP-1R) agonists were shown to exert nephroprotective effects in patients with established DKD, i.e., those who had a reduced glomerular filtration rate. These effects cannot be solely attributed to the improved metabolic control of diabetes. In our review, we attempted to discuss the interactions of both groups of agents with inflammation and oxidative stress—the key pathways contributing to organ damage in the course of diabetes. SGLT2i and GLP-1R agonists attenuate inflammation and oxidative stress in experimental in vitro and in vivo models of DKD in several ways. In addition, we have described experiments showing the same protective mechanisms as found in DKD in non-diabetic kidney injury models as well as in some tissues and organs other than the kidney. The interaction between both drug groups, inflammation and oxidative stress appears to have a universal mechanism of organ protection in diabetes and other diseases. 相似文献
97.
Zusammenfassung In diesem Artikel beschreiben wir die Entwicklung von Interaktivit?t in der Medienkunst, die einhergeht mit der Entwicklung
von Vernetzungsstrukturen und der Herausbildung disziplinübergreifender Arbeitsweisen. Vorwiegend am Beispiel unserer eigenen
Arbeiten der vergangenen 20 Jahre zeichnen wir die Entwicklung interaktiver Kunst von einer neuartigen ?sthetischen Erfahrung
über eine verst?rkte Raumorientierung bis hin zum kulturellen Wissens- und Ged?chtnisspeicher nach. 相似文献
98.
99.
Hilal Şahin Ayhan Topuz Monika Pischetsrieder Feramuz Özdemir 《European Food Research and Technology》2009,230(1):155-161
Roasted carob powder was obtained using different time–temperature combinations and some quality characteristics such as total
phenolic content (TPC), total antioxidant activity (TAA), browning index (BI) at 420 nm, UV absorbance (UV-A) at 294 nm, and
pH has been investigated. Both the roasting temperature and time significantly (P < 0.01) affected the quality characteristics of the product. However, the roasting time was found to be a critical factor
in determining the overall quality of the product. While the TPC, TAA, BI and UV-A values of the samples increased with the
increasing roasting temperature and time, the pH of the samples decreased gradually. The quality characteristics of the carob
powders changed markedly in between 20 and 60 min of roasting which indicates that the heat-induced reactions accelerate particularly
in that period of roasting. The correlations between all these chemical properties of carob powder were found to be significant
(P < 0.0001) during roasting. 相似文献
100.
Barbara Kolsch Prof. Dr. rer. nat. A. Rahmel Monika Schorr 《Materialwissenschaft und Werkstofftechnik》1989,20(11):369-384
Behaviour of gas turbine blade materials under mechanical long term loading and hot gas corrosion. Part 2: Metallographical and microanalytical investigations Results of metallographical and microanalytical investigations on selected specimens after mechanical long term creep and LCF-loading under hot gas corrosion conditions will be presented. Uncoated and MCrAlY or Al-diffusion coated specimens of the polycristalline materials IN-738 LC and IN-939 and the single crystal alloys M 002 mod., CM-SX-6 and B 1914 were investigated. The corrosion attack increases with increasing impurities of the hot gas. Internal nitridation and sulphidation of base material or coating is observed after deterioration of the protective scales rich in Cr2O3 and/or Al2O3. 相似文献