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101.
102.
Nonlinear Dynamics - We consider a two-body problem with quick loss of mass which was formulated by Verhulst (Verhulst in J Inst Math Appl 18: 87–98, 1976). The corresponding dynamical system... 相似文献
103.
Gegova-Dzhurkova R. Nesheva D. Dzhurkov V. Šćepanović M. Grujić-Brojčin M. Bineva I. Mihailov V. Levi Z. Manolov E. Popović Z. V. 《Journal of Sol-Gel Science and Technology》2021,99(1):55-62
Journal of Sol-Gel Science and Technology - Halloysite Nanotubes (HNTs) with large surface/volume ratio and rich reactive groups are incorporated into Fe-based MOF aerogel to develop MOF(Fe)/HNTs... 相似文献
104.
Popović Božidar V. Ristić Miroslav M. Cordeiro Gauss M. 《Mediterranean Journal of Mathematics》2016,13(5):2935-2949
We introduce a new two-parameter lifetime distribution obtained by compounding the generalized exponential and exponential distributions. We assume that the shape parameter of the generalized exponential distribution is a random variable having the exponential distribution. The shapes of the density and hazard rate functions are derived. The model parameters are estimated by maximum likelihood, and an application of the proposed distribution is presented.
相似文献105.
Nikola Saka
Dubravka Maduni-a
i Dean Markovi Lucija Hok Robert Vianello Bojan arkanj Bojan urin Krunoslav Hajdek Boo Smoljan Stjepan Milardovi Brunislav Matasovi Marija Jozanovi 《Molecules (Basel, Switzerland)》2021,26(12)
A 1,3-dihexadecyl-1H-benzo[d]imidazol-3-ium-tetraphenylborate (DHBI-TPB) ion-pair implemented in DHBI-TPB surfactant sensor was used for the potentiometric quantification of anionic surfactants in detergents and commercial household care products. The DHBI-TPB ion-pair was characterized by FTIR spectroscopy and computational analysis which revealed a crucial contribution of the C–H∙∙∙π contacts for the optimal complex formation. The DHBI-TPB sensor potentiometric response showed excellent analytical properties and Nernstian slope for SDS (60.1 mV/decade) with LOD 3.2 × 10−7 M; and DBS (58.4 mV/decade) with LOD 6.1 × 10−7 M was obtained. The sensor possesses exceptional resistance to different organic and inorganic interferences in broad pH (2–10) range. DMIC used as a titrant demonstrated superior analytical performances for potentiometric titrations of SDS, compared to other tested cationic surfactants (DMIC > CTAB > CPC > Hyamine 1622). The combination of DHBI-TPB sensor and DMIC was successfully employed to perform titrations of the highly soluble alkane sulfonate homologues. Nonionic surfactants (increased concentration and number of EO groups) had a negative impact on anionic surfactant titration curves and a signal change. The DHBI-TPB sensor was effectively employed for the determination of technical grade anionic surfactants presenting the recoveries from 99.5 to 101.3%. The sensor was applied on twelve powered samples as well as liquid-gel and handwashing home care detergents containing anionic surfactants. The obtained results showed good agreement compared to the outcomes measured by ISE surfactant sensor and a two-phase titration method. The developed DHBI-TPB surfactant sensor could be used for quality control in industry and has great potential in environmental monitoring. 相似文献
106.
Gyula Argay Alajos Kálmán Béla Ribár Zoltán Djarmati Nikola Tot Ernö Schwirtlich Ratko M. Jankov 《Journal of chemical crystallography》1991,21(5):625-628
The title compound: 2H-10,4a-(epoxy-methano)-phenantren-12-one-1,3,4,9,10,10a-hexahydro-5,6-dihydroxy-9-etoxy-1,1-dirnethyl-7-(1-methylethyl), was isolated fromSalvia officinalis L. andHyssopus officinalis L. C22H30O5, orthorhombic, P212121, (No. 19)a=8.309(1),b=11.320(2),c=22.060(3) Å,V=2075.0(9) Å3,Z=4,D
x=1.199 g·cm–3, (CuK)=1.54184 Å,=6.43 cm–1, F(000)=808,T=296(1) K. The structure was solved by direct methods and refined toR=0.047 for 1824 observed reflections collected on a CAD-4 diffractometer. In the course of structure refinement conformational disorder of the isopropyl moiety and the terminal methyl group pertaining to the ethoxy ligand was established. They result altogether in four different conformers.Alternatively it can be termed 9-ethoxyrosmanol. 相似文献
107.
G. Pavlović V. Tralić-Kulenović M. Vinković D. Vikić-Topić I. Matanović Z. Popović 《Structural chemistry》2006,17(3):275-285
The supramolecular synthon of amide group in the primary and secondary amides is well recognized to be infinite chains of the C(4) type formed by the intermolecular hydrogen bond of the type N–HO=C. On the other hand, there is a lack of structural data for the thioamides. Three compounds belonging to the class of N-aryl-fura-mides (N-(4-bromophenyl)-5-bromo-2-furancarboxamide, N-(4-chlorophenyl)-5-bromo-2-furancarboxamide) and to the class of N-aryl-thiofuramide (N-(4-methoxyphenyl)-2-furanthiocarboxamide) are prepared and characterized by the NMR spectroscopy in solution; molecular and crystal structures in the solid state have been determined by X-ray single crystal diffractometry and the structures in the gas phase by DFT and AM1 calculations. The investigation is carried out in order to establish supramolecular amide and thioamide synthons of hydrogen bonding patterns in these crystal structures. The geometry of the N–HO=C and the N–HS=C type of hydrogen bonds are compared due to the possibility of the N–H amide group to form intramolecular hydrogen bond with the furan oxygen atom, thus, commonly, leading to the three-center hydrogen bond pattern. The competition between the S=C proton acceptor of thioamides and the other proton acceptors (such as methoxy group) for the amide N–H proton donor group has been investigated. In that context, the above-mentioned compounds are correlated with the others of this class, structurally determined, so far. 相似文献
108.
Multifaceted Studies of the DNA Interactions and In Vitro Cytotoxicity of Anticancer Polyaromatic Platinum(II) Complexes 下载免费PDF全文
Benjamin J. Pages Dr. Jennette Sakoff Dr. Jayne Gilbert Prof. Alison Rodger Dr. Nikola P. Chmel Nykola C. Jones Dr. Sharon M. Kelly Dale L. Ang Prof. Janice R. Aldrich‐Wright 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(26):8943-8954
This study reports a detailed biophysical analysis of the DNA binding and cytotoxicity of six platinum complexes (PCs). They are of the type [Pt(PL)(SS‐dach)]Cl2, where PL is a polyaromatic ligand and SS‐dach is 1S,2S‐diaminocyclohexane. The DNA binding of these complexes was investigated using six techniques including ultraviolet and fluorescence spectroscopy, linear dichroism, synchrotron radiation circular dichroism, isothermal titration calorimetry and mass spectrometry. This portfolio of techniques has not been extensively used to study the interactions of such complexes previously; each assay provided unique insight. The in vitro cytotoxicity of these compounds was studied in ten cell lines and compared to the effects of their R,R enantiomers; activity was very high in Du145 and SJ‐G2 cells, with some submicromolar IC50 values. In terms of both DNA affinity and cytotoxicity, complexes of 5,6‐dimethyl‐1,10‐phenanthroline and 2,2′‐bipyridine exhibited the greatest and least activity, respectively, suggesting that there is some correlation between DNA binding and cytotoxicity. 相似文献
109.
110.
Kadoić Nikola Ređep Nina Begičević Divjak Blaženka 《Central European Journal of Operations Research》2018,26(3):611-628
Central European Journal of Operations Research - Using the appropriate methodology for strategic decision-making in higher education is crucial to make effective decisions. In this paper, the... 相似文献