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121.
The principles of construction and the results of testing of a system for measuring P-odd asymmetries in nuclear reactions with polarized cold neutrons by the integrated method of recording events at the neutron
polarization switching frequency above the fundamental frequencies of the reactor power fluctuation spectrum are presented.
It is shown experimentally that if the signal under investigation is characterized by the spectral density of power decreasing
with increasing frequency, switching of the equipment at a higher frequency decreases the measuring error. The dependence
of the error of measurements of P-odd asymmetry in the emission of γ quanta in the 10B(n, α)7Li* ⟹ γ ⟹ 7Li(g.s.) reaction on the neutron polarization switching frequency is derived. The system described here is implemented experimentally
for the first time. 相似文献
122.
Ivana Kovačević Mirjana Popsavin Marko V. Rodić Vesna Kojić Velimir Popsavin 《Tetrahedron letters》2019,60(9):684-687
A new asymmetric synthesis of the naturally occurring styryl lactone cardiobutanolide and two novel analogues have been achieved starting from d-xylose. The key steps of the synthesis included an initial zinc mediated reductive THF-ring opening, stereoselective olefination and Sharpless asymmetric dihydroxylation. It was shown that cardiobutanolide (1) exhibits promising in vitro antitumour properties against certain human neoplastic cell lines. It was more potent than the commercial anticancer agent doxorubicin against three cell lines (K562, HL-60 and Raji). 相似文献
123.
Milena Zivkovic Nenad Zlatic Tijana Zeremski Milan Stankovic Vesna Manic Dragana Krstic Dragoslav Nikezic 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(3):1285-1298
Journal of Radioanalytical and Nuclear Chemistry - Vertical distribution of natural radionuclides, 137Cs and heavy metals were measured in soil and plants collected from Kragujevac surroundings.... 相似文献
124.
Violeta D. Mitić Marija D. Ilić Vesna P. Stankov Jovanović Aleksandra S. Djordjevic Marija S. Marković Gordana S. Stojanović 《Natural product research》2020,34(18):2698-2701
AbstractThe chemical composition of the essential oil and the volatiles obtained by static headspace (HS) of Inula oculus-christi L. is presented. The GC-MS analysis of the hydrodistilled oil resulted in the identification of 90 components, representing 92.7% of the oil. The most abundant compounds were: caryophyllene oxide (9.8%), trans-longipinocarveol (9.2%), eucalyptol (7.3%) and intermedeol (6.2%). The major constituent of I. oculus-christi L. HS volatiles was eucalyptol (87.4%). The antioxidant activity was evaluated by four different methods: 2,2-diphenyl-1-picryl-hydrazylhydrate free radical assay (DPPH), 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) method, total reducing power (TRP), ferric reducing antioxidant power (FRAP), and cupric reducing antioxidant capacity (CUPRAC). Total phenolic content in (TPC) examined oil was 177.95?µg GAE/mg oil. Radical scavenging potential of the oil was promising RSC-DPPH was 57.4% and RSC-ABTS was 82.7%. 相似文献
125.
Manić Vesna Manić Goran Stojanović Miloš Radojković Branko Krstić Dragana Nikezić Dragoslav 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(2):671-677
Journal of Radioanalytical and Nuclear Chemistry - The activity concentration of natural radionuclides in the samples of soil from the town of Ni? were measured using the gamma spectroscopy... 相似文献
126.
Rodrigues JV Prosinecki V Marrucho I Rebelo LP Gomes CM 《Physical chemistry chemical physics : PCCP》2011,13(30):13614-13616
Protein stability is a major bottleneck in the biotechnological application of ionic liquid-containing solvents, either in the frame of biocatalysis or protein storage. Herein, differential scanning fluorimetry was successfully implemented as a high throughput method to fast scan the impact of a number of cholinium-based ionic liquids on the stability of proteins. 相似文献
127.
Many interesting topologies arise in the theory of FK spaces. Here we present some new results on the topologies of certain FK spaces and the determinations of their dual spaces. We also apply our software package for visualization and animations in mathematics and its extensions to the representation of neighborhoods in various topologies. 相似文献
128.
Darka Mihailović Zoran Šaponjić Vesna Vodnik Branislav Potkonjak Petar Jovančić Jovan M. Nedeljković Maja Radetić 《先进技术聚合物》2011,22(12):2244-2249
This study is aimed to highlight the possibility of engineering the multifunctional textile nanocomposite material based on the polyester (PES) fabric modified with colloidal Ag and TiO2 nanoparticles (NPs). The effects of concentration of NPs as well as the order of Ag and TiO2 NPs loading on antimicrobial, UV protective, and photocatalytic properties of PES fabrics were examined. The antimicrobial activity of differently modified PES fabrics was tested against Gram‐negative bacterium Escherichia coli, Gram‐positive bacterium Staphylococcus aureus, and fungus Candida albicans. The concentration of Ag colloid and the order of Ag and TiO2 NPs loading considerably affected the antimicrobial efficiency of PES fabrics. The fabrics provided maximum UV protection upon surface modification with Ag and TiO2 NPs. Ag NPs enhanced Ag NPs enhanced the photodegradation activity of TiO2 NPs and total photodegradation of methylene blue was achieved after 24 hr of UV illumination. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
129.
Gordana Stojanović Ivana Zrnzević Ivana Zlatanović Miroslava Stanković Vesna Stankov Jovanović Violeta Mitić 《Natural product research》2020,34(4):549-552
AbstractThe aim of this study was to determine, for the first time, the chemical composition of Peltigera horizontalis thallus and apothecia extracts (ether, ethyl acetate, dichloromethane and acetone) by HPLC-UV and GC-MS, and evaluate activity of genotoxic, anticholinesterase, antioxidant and antibacterial potential of acetone extracts. Major constituents of thallus extracts were gyrophoric acid, and methyl gyrophorate while dominant component of apothecia extracts was tenuiorin. The predominant volatile compounds in extracts were methyl orsellinate, dodecyl acrylate, orcinol and orcinol monomethyl ether. The thallus acetone extract at concentration of 2.0 µg mL?1 gave the greatest decrease in the micronuclei frequency (22.4%) of all tested extracts. Apothecia extract showed stronger antioxidant activity as compared to thallus extract. Tested extracts at concentration of 10?mg mL?1 exhibited inhibitory effect (16.5% for thallus and 12.8% for apothecia) on pooled human serum cholinesterase. P. horizontalis acetone extracts had no activity against the tested five bacteria strains. 相似文献
130.
Summary : The Raman spectra of aminopropylsiloxane (APS) polymerized on PVC substrate in DC electric field were measured to study the structure of deposited films. The modelling of low wavenumber Raman spectra was achieved using contribution of acoustic phonons, intramolecular vibrations as well as optical phonons related to librational motions of ladders. Results suggest that electric field influences the orientations of ladders increasing thus the degree of order in microdomains. 相似文献