Методами рентгеновской фотоэлектронной спектроскопии и рентгеновской спектроскопии поглощения исследована электронная структура биметаллических наносплавов состава Os0.5Pt0.5. На основании экспериментальных данных определены электронная заселенность на атомах в сплавах. Показано, что при образовании сплава происходит перенос электронов с атомов Os на Pt, а знак и величина химического сдвига в значительной степени определяется потенциалом Маделунга. Анализ формы спектров РФЭС внутренних линий и валентной полосы показывает увеличение локальной плотности состояний на атомах Os вблизи уровня Ферми. На основании параметров валентной d-зоны обсуждаются перспективы использования наносплавов в каталитических реакциях.

The electronic structure of Os0.5Pt0.5 bimetallic nanoalloys is studied by X-ray photoelectron spectroscopy and X-ray absorption spectroscopy. The electronic population on the atoms of these alloys is determined from the obtained experimental data. It is shown that the alloy formation is accompanied by electron transfer from Os atoms to Pt atoms, while the sign and magnitude of the chemical shift are largely determined by the Madelung potential. The shape of the XPS spectra of core lines and the valence band indicate that the local density of states increases on the Os atoms near the Fermi level. Prospects of using the nanoalloys in catalytic reactions are discussed by analyzing the valence d-band parameters.

Уважаемые коллеги!Благодарим Вас за проявленный интерес к Четвертой российской конференции «Графен: молекула и 2D кристалл» и желание принять участие в её работе.Конференция проходит в научно-образовательном центре города Новосибирска -Академгородке.Мероприятие посвящено актуальным направлениям исследований и разработок в области углеродных и низкоразмерных материалов.Проведение конференции поможет координации усилий ученых в решении современных проблем материаловедения и привлечению молодых исследователей для решения актуальных научных задач.Оргкомитет выражает особую благодарность НГУ, Центру компетенций НТИ «Моделирование и разработка новых функциональных материалов с заданными свойствами», компаниям «Диаэм», «НТ-МДТ Спектрум Инструментс» и корпорации "Графеновая Долина" за финансовую поддержку и журналам Аналитика, Наноиндустрия и РЭНСИТ за информационную поддержку.Искренне надеемся, что пребывание в Новосибирском Академгородке и в стенах Новосибирского государственного университета оставит множество положительных эмоций и

Министерство науки и высшего образования Российской Федерации Российская академия наук Научный совет по неорганической химии РАН Научный совет по аналитической химии РАН Научный совет по химической технологии РАН Российское химическое общество имени Д.И

Министерство науки и высшего образования Российской Федерации Российская академия наук Научный совет по неорганической химии РАН Научный совет по аналитической химии РАН Научный совет по химической технологии РАН Российское химическое общество имени Д.И

Nowadays, Pt-Os binary systems are mainly considered as catalysts and electrocatalysts, but the role of Os in these processes is still poorly understood. The electronic structure of Pt-Os nanosystems remains a few studied as well. Using bimetallic (NH4)2[Pt0.5Os0.5Cl6] as a single-source precursor for preparing Pt-Os nanoalloy through the thermal decomposition in hydrogen and inert atmospheres, the relation of morphology, atomic ordering, and electronic structure of Pt-Os nanoalloy was examined by in situ Quick XAFS, XPS, PXRD, SEM, and HRTEM techniques. Being the only variable parameter, the decomposition atmosphere was found to govern the morphology of the Pt-Os nanoalloy and change the atomic ordering (alloying extent), which involves a change in the electronic structure. In a hydrogen atmosphere, the nanofibers (NFs) (ø ~ 5–6 nm) with the atomic ordering Oscore&Pt-richshell were observed to form; in a nitrogen atmosphere, thin nanoplates (NPLs) (~ 12 nm) with the atomic architecture Os-richcore&Pt-richshell were found out. The depletion in the Os 5d5/2 and Pt 5d5/2,3/2 states was revealed for Pt-Os nanoalloys. This unusual result disagrees with the known d-band theory and indicates that there is a gain of non-d conduction electron counts at one or both sites. Mixed conductivity may exist in such Pt-Os nanoalloy that may be responsible for a manifestation of new physical properties of this binary system .

X-ray emission spectroscopy and static magnetochemistry study of CuCr1-xVxS2(x = 0 divided by 0.40) was carried out. The atom charge were estimated using the core-level S, V, Cr and Cu(K alpha)-lines energy. The additional data on the electron density distribution on the vanadium and copper atoms were studied analyzing the V(L alpha) and Cu(L alpha, beta) spectra fine structure features. The charge distribution in the CuCrS2 matrix was found to be Cu+Cr3+ (S2-)(2). In the case of low vanadium concentrations x < 0.15 both Cu+Cr3+ (S2-)(2) and Cu(0+delta)Cr(1-x)((4-delta)+)Vx((4-delta))(+)(S2-)(2)(delta -> 0) charge/magnetic configurations were found. The charge distribution for solid solutions doped with concentration x = 0.15 divided by 0.40 was described as Cu+Cr1-x3+Vx3+(S-2(-))(2). The obtained data on the charge/magnetic configurations is in good agreement with the magnetochemical measurements results. The oxidation state changes could be due to the defectness caused by intercalation of the vanadium atoms into the copper sublattice.

The oxidation state studies of Mn(1-x)Ln(x)S (Ln = Dy, Tm, Yb; x = 0; 0.01; 0.05) solid solutions was carried out for the first time using X-ray photoelectron and emission spectroscopy. The binding energy of the S(2p)-, Ln(4d)-, multiplet splitting analysis of Mn(3s)-level and the SK alpha(1)-line energy position allow one to determine atoms oxidation state. The lanthanide atoms were found to be in the trivalent, while the manganese and sulfur atoms were in the divalent state. The near-surface layers contain sulfur atoms in the 0, +4 and +6 oxidation states. The obtained data on the oxidation state were compared with those in lanthanide sulfides Ln(2)S(3) (Ln = Dy, Tm, Yb). The additional 4f-electrons emerged after cationic substitution are assumed to be delocalized in the conduction band and affect physical properties of doped manganese monosulfide. The oxidation state of lanthanide and manganese atoms both on the surface and in the bulk was found to be the same in the compounds studied. The surface layer doesn't contain an additional metal oxidation states (magnetic scattering centers) that significantly affect the colossal magnetoresistance.

Crystal structures of [Dy(dpm) 3 ] 2 ( 1 ) at 155(2) K (space group P 2 1 / n , a = 12.2191(3) Å, b = 27.6044(6) Å, с = 21.8615(5) Å, β = 105.172(1)°, V = 7116.9(3) Å 3 , Z = 4) and Dy(dpm) 3 ( 2 ) at 200(2) K (space group P mn 2 1 , a = 17.8741(7) Å, b = 10.5639(4) Å, с = 9.8336(4) Å, V = 1856.78(13) Å 3 , Z = 2) are determined. The structure of complex 1 is similar to the previously known dimeric packings [Ln(dpm) 3 ] 2 (Ln = La, Pr, Nd, Eu, Gd, Tb). Complex 2 is isostructural to the previously studied molecular complexes Er(dpm) 3 and Lu(dpm) 3 . At room temperature the luminescence quantum yield (QY) of Tb(dpm) 3 is found to reach 77% and that of Dy(dpm) 3 is 5%, while for the other Lu(dpm) 3 complexes, where Ln = Pr, Nd, Sm, Eu, Gd, Ho, Er, Tm, Yb, QY is below 1%. A series of [Tb(dpm) 3 ] 2 and Dy(dpm) 3 solid solutions is obtained by evaporating mixtures from solutions. Molecular films of these complexes on Si, Cu, Ni, Ti, KBr substrates are obtained by vacuum deposition.

A technique has been developed for determining mercury content in the concentration range of 1–1000 μg/g in hair samples by X‐ray fluorescence analysis using synchrotron radiation (synchrotron radiation X‐ray fluorescence, Siberian Synchrotron and Terahertz Radiation Center, Budker Institute of Nuclear Physics SB RAS). The mercury content was identified in archeological hair samples from an ancient burial of Xiongnu nobility (Mongolia, mound 22, 1st century BC–1st century AD); the content values were elevated (up to 1100 μg/g) in all the samples (n = 41). An X‐ray microanalysis using polycapillary lenses in a confocal scheme (confocal X‐ray microscopy station) was developed at the Synchrotron radiation X‐ray fluorescence to establish mercury distribution in a cross section of hair shaft with a spatial resolution of 5 μm. The findings of the study make it possible to assume exogenous income of mercury (from the burial environment) to the hair.

In rats with obesity induced by high fat ration, the concentrations of K, Ca, Mn, Fe, Cu, Zn, Se, Br, Rb, and Sr were measured in the liver and lungs using synchrotron X-ray fluorescence analysis. Recombinations of inter-element correlations in the liver and lungs of rats receiving or not receiving additional Zn were observed under fasting conditions and after eating lard. Sr and Ca made the most pronounced contribution in the redistribution of correlations in the liver of obese rats. In contrast to other bioelements, Sr had negative correlations with all study elements in the liver of obese rats during physiological starvation. Long-term administration of Zn to rats was followed by recombination of both fasting and postprandial inert-element correlations in the liver and lungs, but Zn concentration did not change under these conditions. Redistribution of correlations in the liver and lungs of obese rats under fasting conditions reflects fundamental changes in metabolic processes, while redistribution observed after fat meal indicates temporary (postprandial) changes.

The brief review has been presented about the application of X-ray fluorescent analysis using synchrotron radiation (storage ring VEPP-3, BINP SB RAS) for determination of elemental composition of the samples of different nature–biological and geological samples, objects of environment, archeological objects, and new materials. The feature of the presented research is the employment of the unique properties of synchrotron radiation, which allow analyzing samples of small mass (of the order of several milligrams), and also scanning core of bottom sediments with high resolution (less than 1 mm) that is not practical to realize by traditional analysis methods.

Ge K edge EXAFS (Extended X-Ray Absorption Fine Structure) spectra have been measured for multilayer semiconducting heterosystems containing interacted groups of quantum dots (“molecules from quantum dots”) ordered in rings on different stages of their growth depending on topologic parameters and growth conditions. In accordance with our results obtained previously for the quantum dots of SiGe, for the molecules of quantum dots it was found that deformation at the interface leads to decrease in the interatomic distance of Ge–Ge by ~0.03 Å. Effect of heterosystem topology and temperature at different stages of their growth on interlayer diffusion was investigated. It was found that at the first growth stage (growth of “seeded islands” serving as a basis for obtaining the molecules) at 700°C a concentration of Ge atoms in the system is ~38%. With further growth of the vertically-matched quantum dots groups the concentration of Ge increases up to ~43-47% depending on the growth conditions. Comparable analysis of different modes of EXAFS measurements was performed to determine precisely structural parameters of heterosystem SiGe with different thickness grown on Si(100) surface.

We found no deviations from normalcy in the content of chemical elements (K, Ca, Mn, Fe, Cu, Zn, Se, Br, Rb, and Sr) in the lungs of rats with mild alimentary obesity, but revealed redistribution of correlations between the elements indicating impaired metabolism in this organ. Zinc supplementation had no effect on the body weight and content of chemical elements (including zinc) in the lung tissue in rats fed high fat diet, but led to significant changes in the correlations between the elements. Bromine, rubidium, and strontium are actively involved in interelement interactions in the lung tissue. These elements should be given more attention in considering biological processes including alimentary obesity.

We present results of study of the bottom sediments of proglacial Lake Ekhoi, which is fed with the Peretolchin Glacier meltwater (East Sayan). The bottom deposit sequence, formed from 1885 to 2013, was investigated with a year-season time resolution, using X-ray fluorescence with synchrotron radiation (with and without scanning), the Fourier-transform infrared (FTIR) analysis, and color processing of core photos. The depth-age model of the core was based on counting of annual laminate layers with control by Pb-210, Cs-137, U-238, and Ra-226 chronology. Intense glacier thawing was calculated from the amount of clastic matter supplied by the glacier meltwater into the lake. The elemental composition of the bottom sediments includes three groups reflecting periods of displacement of the glacier front and the intensity of evolution of aquatic biota. The first group of elements (Ca, K, Ti, Fe, and Mn) characterizes the supply of clastic matter without serious changes in the glacier edges. The second group (Ni, Cu, Br, and U) is responsible for the intensity of evolution of aquatic biota. Finally, the third group (Rb, Sr, Zr, Nb, Y, and Th) can describe the intensity of displacement of the glacier front. Intensive glacier thawing has proceeded since 1920; however, the glacier retreat was insignificant till 1947. From 1947 to 1970, the glacier rapidly retreated, especially in the period 1953-1970. This was induced by steady high regional summer surface temperature in 1938-1970. The following glacier retreat was during 1980-2000, synchronously with the global temperature anomaly in the Northern Hemisphere. Since 2000, the melting has slowed. (C) 2015, V.S. Sobolev IGM, Siberian Branch of the RAS. Published by Elsevier B.V. All rights reserved.

Results from studying the bottom sediments of proglacial Lake Ehoy, deposited by meltwaters of the Peretolchin Glacier in the Eastern Sayan Ridge, are presented. The bottom sediments formed between 1885 and 2013 are investigated with a time resolution of years and seasons by means of X-ray fluorescence with synchrotron radiation in the scanning and traditional modes (SR-XRF scanning, SR-XRF), infrared spectroscopy analysis, and the color processing of core photographs.

The paper presents a study of bottom sediments of proglacial Lake Ehoy, which intakes the meltwater of Peretolchin glacier, the East Sayan Ridge. A bottom sediment sequence that formed in the period of 1885–2013 was investigated with a year/season time resolution using X‐ray fluorescence with synchrotron radiation and conventional analysis. A depth‐age model of the core was based on counting of the annual laminae. The model was checked by an analysis of the distribution of activity of 210Pb, 137Cs, 238U, and 226Ra. The dynamics of the glacier is considered through the intensity of clastic material inflow into the lake with the glacier melt water. In the elemental composition of the sediments, there are three groups of elements that reflect the periods of movement of the front edge of the glacier and the intensity of development of the aquatic biota. The first group of elements (Ca, K, Ti, Fe, and Mn) characterizes the inflow of clastic material when there are no significant changes in the boundaries of the glacier. The second group of elements (Ni, Cu, Br, and U) reflects the aquatic biota intensity. The third group of elements (Rb, Sr, Zr, Nb, Y, and Th) is some evidence that the displacement of the front edge of the glacier was significant. The glacier retreated rapidly in 1947–1970. The next period of steady degradation of the glacier took place in 1980–2000. Since 2000, the melting rate has slowed down. Copyright © 2015 John Wiley & Sons, Ltd.

The direct analysis of the biological tissue samples is a great advantage of the X-ray Fluorescent Technique with Synchrotron Radiation (SRXRF). SRXRF method is realized on the basis of INP SB RAS in Siberian Synchrotron and Terahertz Radiation Centre. In the present work, the whole liver tissue samples were dried under weight and analyzed in the form of parallel-plane fragments. The minimization of sample preparation procedures is known to significantly reduce the risks of the sample contamination and loss of analyte. The preparation procedure, which was used in the present work, was carried out without lyophilization, grinding and pelletizing of liver tissue samples. Elemental concentrations in the samples were calculated using the calibration and constructed on the basis of biological certified reference materials. It was found that there weren’t any significant differences between elemental concentrations in the case of the direct analysis of parallel-plane liver fragments and concentrations obtained for the same liver samples after grinding and pelletizing. Two unbroken samples and one grinded sample were measured 5 times to assess the reproducibility. The relative standard deviation for each sample was calculated, and it included both the assessment of the reproducibility and the heterogeneity of the elemental distribution in the sample. The validation of the results obtained by SRXRF method was estimated by the comparison with the results obtained by another method, namely by Two-Jet Plasma Atomic Emission Spectrometry (TJP-AES). Thereby the offered way of sample preparation procedure using external standard method for calculation of elemental concentrations can be applied for SRXRF analysis of biological samples. Keywords : x-ray fluorescent analysis, synchrotron radiation, sample preparation, biological tissue, liver (Russian) DOI: http://dx.doi.org/10.15826/analitika.2015.19.2.008 V.A. Trunova 1,2 , A.V. Sidorina 1 , V.V. Zvereva 1 1 A.V. Nikolaev Institute of Inorganic С hemistry SB RAS, Novosibirsk, Russian Federation 2 Novosibirsk State University , Novosibirsk, Russian Federation