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61.
We obtain a joint universality theorem for periodic Hurwitz zeta-functions under weaker hypotheses than those in the previous
papers of the first author. 相似文献
62.
Andrius Garbaras Justina Šapolaitė Inga Garbarienė Žilvinas Ežerinskis Agnė Mašalaitė-Nalivaikė Raminta Skipitytė 《Isotopes in environmental and health studies》2018,54(5):463-474
In the present study, a combination of the stable carbon isotope ratio (13C/12C) with radiocarbon data (14C) allowed us to perform the aerosol source apportionment. Filter samples of PM1 were collected during the warm and cold periods in rural and urban sites in Lithuania. The 14C/12C ratio of total carbon (TC) was measured using the single stage accelerator mass spectrometer quantifying of fossil and non-fossil derived aerosol emissions. The δ13C value was measured using an elemental analyser interfaced with an isotope ratio mass spectrometer. We have found that the highest fraction of contemporary carbon (fc?=?0.82) was measured during a warm period in a rural location. A higher fraction of fossil fuel-derived carbon was observed for air masses transported from highly industrialized Western European regions during both seasons. Isotope mass balance calculations revealed that the traffic emissions composed 15 and 25?% in rural and urban sites, respectively, and did not change during either season. Input from coal-derived aerosol particles was estimated to be 15?% at an urban site during the cold period. The combination of the stable carbon isotope ratio with the radiocarbon data allowed us to distinguish coal, liquid fossil fuel combustion, and non-fossil derived aerosol particle emissions. 相似文献
63.
Misiūnas A Niaura G Barauskas J Meškys R Rutkienė R Razumas V Nylander T 《Journal of colloid and interface science》2012,378(1):232-240
Small angle X-ray diffraction (SAXD), resonance Raman (RR) spectroscopy with 413 nm excitation, and non-resonance Raman technique with 785 nm excitation were used to probe the influence of entrapped cytochrome c (Cyt c) on the structure of hydrated phytantriol (Phyt) liquid-crystalline phases as well as conformational changes of heme group and secondary structure of the protein. SAXD measurements indicated that incorporation of Cyt c affects both nanostructure dimensions and type of liquid-crystalline phases of hydrated Phyt. The unit cell dimensions decrease with increasing Cyt c concentration for all phases. In addition, protein perturbs the nanostructure of Q(230) and Q(224) liquid-crystalline phases of hydrated Phyt to such an extent that they transform into the Q(229) phase with the Im3m space group. RR data revealed that entrapment of oxidized Cyt c into the Q(230) phase at 1 wt.% content results in near complete reduction of central iron ion of the heme group, while its low-spin state and six-ligand coordination configuration are preserved. Based on the analysis of heme out-of-plane folding vibration near 568 cm(-1) (γ(21)) and ν(48) mode at 633 cm(-1), it was demonstrated that the protein matrix tension on the heme group is relaxed upon incorporation of protein into Q(230) phase. Non-resonant Raman bands of difference spectra showed the preservation of α-helix secondary structure of Cyt c in the liquid-crystalline phase at relatively high (5 wt.%) content. The Cyt c induced spectroscopic changes of Phyt bands were found to be similar as decrease in temperature. 相似文献
64.
A. Krotkus V. Pačebutas J. Kavaliauskas I. Subačius K. Grigoras I. Šimkienė 《Applied Physics A: Materials Science & Processing》1997,64(4):357-360
Received: 10 May 1996/Accepted: 19 November
1996 相似文献
65.
66.
67.
J. Sakalauskaitė 《Lithuanian Mathematical Journal》2007,47(3):266-276
In this paper, we consider branching time temporal logic CT L with epistemic modalities for knowledge (belief) and with awareness operators. These logics involve the discrete-time linear
temporal logic operators “next” and “until” with the branching temporal logic operator “on all paths”. In addition, the temporal
logic of knowledge (belief) contains an indexed set of unary modal operators “agent i knows” (“agent i believes”). In a language of these logics, there are awareness operators. For these logics, we present sequent calculi with
a restricted cut rule. Thus, we get proof systems where proof-search becomes decidable. The soundness and completeness for
these calculi are proved.
Published in Lietuvos Matematikos Rinkinys, Vol. 47, No. 3, pp. 328–340, July–September, 2007. 相似文献
68.
Possibilities to increase the sensitivity of stripping analysis by optimising the hydrodynamic conditions of the solution during the deposition and rest period are evaluated. Rotation rates as high as 13 000 rpm can be applied during the deposition step at a mercury film rotating disc electrode for Zn, Cd, Pb, In and Tl determinations when 10-20 mg/l of Hg(2+) for the renewal of the mercury film is added. Because of the extreme sensitivity on the properties of the mercury film in the case of Ga only 4000-5000 rpm are recommended. The highest stirring efficiencies using a magnetic stirrer are equivalent to 2500-3000 rpm when a rotating disc electrode is used. The effect of the duration of the rest period is not significant for square wave stripping voltammetry, however, analytical signals can be increased 10 and more times when potentiometric stripping analysis is applied. 相似文献
69.
The effects of different
cationic surfactants (n-undecylammonum chloride, UDACl and dodecyldimethyl
(dodecyloxymethyl) ammonium chloride, DDMDDACl) on fully hydrated 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) vesicles have
been studied. In the studied systems the molar ratio (x)
of DPPC/surfactant ranged between x=0.0164–0.82
and from x=0.0352–1.76 for DPPC/DDMDDACl
and DPPC/UDACl, respectively. For both systems, the enthalpy associated with
the phase transition significantly decreases even at the lowest surfactant
concentration. Also the main phase transition temperature is shifted towards
lower temperatures.
The structural parameters of the phases have
been characterised by small angle X-ray scattering (SAXS). The SAXS results
have proved that UDACl at x=0.0352 molar
ratio significantly influences the DPPC lamellar structure, while its total
disappearance was observed for x=0.176.
The presence of DDMDDACl causes a total disappearance of the DPPC lamellar
structure already at the lowest molar ratio (x=0.0352).
Each surfactant in the system with DDPPC leads to a mixed micellar phase formation. 相似文献
70.
Olek M Kempa K Jurga S Giersig M 《Langmuir : the ACS journal of surfaces and colloids》2005,21(7):3146-3152
The mechanical properties of polymer composites, reinforced with silica-coated multiwall carbon nanotubes (MWNTs), have been studied using the nanoindentation technique. The hardness and the Young's modulus have been found to increase strongly with the increasing content of these nanotubes in the polymer matrix. Similar experiments conducted on thin films containing MWNTs, but without a silica shell, revealed that the presence of these nanotubes does not affect the nanomechanical properties of the composites. While carbon nanotubes (CNTs) have a very high tensile strength due to the nanotube stiffness, composites fabricated with CNTs may exhibit inferior toughness. The silica shell on the surface of a nanotube enhances its stiffness and rigidity. Our composites, at 4 wt % of the silica-coated MWNTs, display a maximum hardness of 120 +/- 20 MPa, and a Young's modulus of 9 +/- 1 GPa. These are respectively 2 and 3 times higher than those for the polymeric matrix. Here, we describe a method for the silica coating of MWNTs. This is a simple and efficient technique, adaptable to large-scale production, and might lead to new advanced polymer based materials, with very high axial and bending strength. 相似文献