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Large-scale error-tolerant programmable interferometer fabricated by femtosecond laser writing

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Photonics Research 2024年第3期12卷 I0028-I0040页

作者： ILYA KONDRATYEv vERONIKA IvANOvA SUREN FLDZHYAN ARTEM ARGENCHIEv nikita KOSTYUCHENKO SERGEY ZHURAvITSKII NIKOLAY SKRYABIN IvAN DYAKONOv MIKHAIL SAYGIN STANISLAv STRAUPE ALEXANDER KORNEEv SERGEI KULIK Quantum Technology Centre and Faculty of Physics M.V.Lomonosov Moscow State UniversityMoscow 119991Russia Russian Quantum Center Moscow 121205Russia Laboratory of Quantum Engineering of Light South Ural State UniversityChelyabinsk 454080Russia

We introduce a programmable eight-port interferometer with the recently proposed error-tolerant architecture capable of performing a broad class of *** interferometer has been fabricated with femtosecond laser writing,and it is the largest programmable interferometer of this kind to *** have demonstrated its advantageous error tolerance by showing an operation in a broad wavelength range from 920 to 980 nm,which is particularly relevant for quantum photonics due to efficient photon sources existing in this wavelength *** work highlights the importance of developing novel architectures of programmable photonics for information processing.

关键词： interferometer laser femtosecond

Highly selective/enantioselective Pt-ReOx/C catalyst for hydrogenation of L-malic acid at mild conditions

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Journal of Energy Chemistry 2018年第3期27卷 903-912页

作者： Bair S.Bal'zhinimaev Eugene A.Paukshtis Alexey P.Suknev nikita v.Makolkin Boreskov Institute of Catalysis SB RA5 Prospect Akademika Lavrentieva5Novosibirsk 630090Russia

The catalyst preparation strategy was based on a strict introduction sequence of rhenium and platinum precursors and their strong interaction with carbon support resulted in the formation of 0.5 nm Pt-Re Ox species of atomic dispersion, where platinum is metallic, while monolayer rhenium is partially oxidized（Re2＋）. The reaction kinetics was studied taking into account the process of L-malic acid association leading to the formation of inactive cyclic oligomeric species. High TOFs（ca. 50 h-1）, selectivities（ca. 99%）and stability of Pt-Re Ox/C catalysts in aqueous-phase hydrogenation of L-malic acid, which are close to those of the homogeneous pincer type complexes, were revealed at mild conditions（T = 90–130 ℃）. Taking into account that（i） hydrogenation reaction occurred 2–3 orders of magnitude faster than its racemization and（ii） association of L-malic acid dominates at low temperatures and in a concentrated solution,special reaction conditions that allow obtaining chemically and optically（ee 〉 99%） pure（S）-3-hydroxy-γ-butyrolactone and（S）-1,2,4-butanetriol were found. Basing on HAADF-STEM, EDX, XPS, and kinetic studies, the structure of active species and basic reaction pathways are proposed.

关键词： L-malic acid Hydrogenation Enantioselectivity Platinum Rhenium Atomic dispersion

Mechanism of the Initial Stage of Thermal Decomposition of Nitroguanidine

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火炸药学报 2023年第1期46卷 31-40页

作者： Boris E.Krisyuk Danila A.Markin Timofey M.Sypko viktor v.Zakharov nikita v.Chukanov Boris L.Korsunskiy Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry Russian Academy of Sciences142432prosp.Academician Semenov1ChernogolovkaMoscow RegionRussia Plekhanov Russian University of Economics Department of Chemistry and Physics36 Stremyanny laneMoscow 117997Russia Lomonosov Moscow State University Faculty of Fundamental Physical and Chemical engineeringGSP-11 Leninskie Goryp.51Moscow 119991Russia N.N.Semenov Federal Research Center for Chemical Physics Russian Academy of Science 4 Kosygina StreetBuilding 1Moscow 119991Russia

A theoretical and experimental study of the thermal decomposition of nitroguanidine(NQ) has been carried out. various thermolysis channels were studied by quantum chemistry methods at the CCSD(or DLPNO-CCSD) level using the aug-cc-pvDZ basis set. It is shown that the lowest activation enthalpies(170-180kJ/mol) are characteristic of the reactions of NO2abstraction from the initial NQ and the reaction channel with the transfer of oxygen from the nitro group to carbon in the limiting stage. Additionally, the thermolysis of NQ was studied experimentally in a nonisothermal mode with heating rates from 1 to 10K/min. In these experiments, the weight loss of the sample, thermal effects, and mass spectra of the products were recorded. An analysis of the experimental data confirmed the results of a theoretical study of the mechanism of thermal decomposition of NQ. The main thermolysis products are N2O, HNCO, NH3, and NO2, which fully corresponds to quantum chemical calculations.

关键词： primary thermolysis steps quantum-chemical calculation mass spectrometry DSC TG

Calcium Carbide:From Elemental Carbon to Isotope-Economic Synthesis of^(13)C_(2)-Labeled Heterocycles

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Chinese Journal of Chemistry 2023年第21期41卷 2810-2818页

作者： Maria S.Ledovskaya vladimir v.voronin nikita R.valov Dmitriy E.Samoylenko Saint Petersburg State University Institute of ChemistryUniversitetsky prospect 26Peterhof198504 Russia

^(13)C-Carbon is the most available source of *** is a relatively inexpensive solid material,which can be easily converted to calcium carbide-^(13)C_(2).In current work,Ca^(13)C_(2)was used for in situ generation of^(13)C_(2)-acetylene in 1,3-dipolar cycloaddition and[4+2]cycloaddition *** the first time,1H-1,2,3-triazoles-4,5-^(13)C_(2)and isoxazoles-4,5-^(13)C_(2)were synthesized using calcium carbide-^(13)C_(2).A Diels-Alder type cycloaddition of 3,6-di(pyridin-2-yl)-1,2,4,5-tetrazine and Ca^(13)C_(2)was investigated,and the best way for the synthesis of 3,6-di(pyridin-2-yl)pyridazine-4,5-^(13)C_(2)was proposed for the first *** we perform a detailled description of NMR spectra of^(13)C_(2)-labeled triazoles,isoxazoles and 3,6-di(pyridin-2-yl)pyridazine.

关键词： Isotopic labeling Cycloaddition Click chemistry Sustainable Chemistry Calcium carbide

Generation of synchronized x-rays and mid-infrared pulses by Doppler-shifting of relativistically intense radiation from near-critical-density plasmas

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Matter and Radiation at Extremes 2023年第2期8卷 6-13页

作者： nikita A.Mikheytsev Artem v.Korzhimanov Lobachevsky State University of Nizhny Novgorod 603022 Nizhny NovgorodRussia Federal Research Center Institute of Applied Physics of the Russian Academy of Sciences 603950 Nizhny NovgorodRussia

It is shown that when relativistically intense ultrashort laser pulses are reflected from the boundary of a plasma with a near-critical density,the Doppler frequency shift leads to generation of intense radiation in both the high-frequency(up to the x-ray)and low-frequency(mid-infrared)*** efficiency of energy conversion into the wavelength range above 3μm can reach several percent,which makes it possible to obtain relativistically intense pulses in the mid-infrared *** pulses are synchronized with high harmonics in the ultraviolet and x-ray ranges,which opens up opportunities for high-precision pump–probe measurements,in particular,laser-induced electron diffraction and transient absorption spectroscopy.

关键词： pump intense relativistic

Tumor cell death visualization of renal cell carcinoma under the combined effect of the Gratiola officinalis extract and cyclophosphamide using fluorescent staining methods

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Journal of Innovative Optical Health Sciences 2021年第5期4卷 46-52页

作者： Artyom Mylnikov nikita Navolokin Dmitry Mudrak Natalya Polukonova Alla Bucharskaya Galina Maslyakova Saratov State Medical University named after V.I.Razumovsky 112 Bolshaya Kazachia Street Saratov 410012Russia National Research Saratov State University 83 Astrakhanskaya Street Saratov 410012Russia National Research Tomsk State University 36 Lenin Avenue Tomsk 634050Russia

Objective of the study:We used fluorescence imaging methods of apoptosis and necrosis in human renal carcinoma A498 tumor cells in vitro to reveal the indicated forms of cell death under the combined effect of flavonoid-containing extract of Gratiola officinalis and cytostatic(cyclo-phosphamide).Materials and methods:The dyes were propidium iodide and acridine orange,which were used in the"alive and dead"*** test helped us to identify the total number of dead cells in the forms of necrosis and apoptosis and the number of cells in which apoptosis had started,it was characterized by the appearance of apoptotic bodies or nucleus ***:We found the most pronounced cytotoxic activity at the ratio of extract of Gratiola officinalis and cyclophosphamide concentrations of 1∶*** number of living cells decreased when exposed to the ratio of extract and cytostatic concentrations of 2∶*** the ratio of concentration of the extract relative to the cytostatic increased to 3∶1,the cytostatic activity of the extract began to appear,the total number of tumor cells *** number of cells with nucleus pyknosis and the number of cells with apoptosis signs significantly increased at a 3∶1 ratio of extract and cytostatic concentrations,which confirms the presence of pro-apoptotic activity of the studied *** trend indicates the dependence of a certain form of cell death(apoptosis,necrosis)on the ratio of extract and cytostatic doses,and it also demon-strates the cytostatic and cytotoxic effects of this ***:Fluorescence methods of investigation in the"alive and dead"test allowed us to visualize the forms of cell death of human kidney carcinoma A498 by combined exposure to the fiavonoid-containing extract of Gratiola officinalis and cytostatic(cyclophosphamide)24 h after *** found that the combination with a concentration ratio of the extract and cyclophosphamide of 3:1 has the greatest effectiveness due to stimulation of t

关键词： A498 cell line Gratiola officinalis extract antitumor activity cytostatic activity flavonoids fluorescent methods kidney cancer

The optical tweezer of skyrmions

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npj Computational Materials 2020年第1期6卷 484-490页

作者： Xi-Guang Wang Levan Chotorlishvili vitalii K.Dugaev Arthur Ernst Igor v.Maznichenko nikita Arnold Chenglong Jia Jamal Berakdar Ingrid Mertig Józef Barnaś School of Physics and Electronics Central South University410083 ChangshaChina Institut für Physik Martin-Luther Universität Halle-Wittenberg06099 HalleSaaleGermany Department of Physics and Medical Engineering Rzeszów University of Technology35-959 RzeszówPoland Institute for Theoretical Physics Johannes Kepler UniversityAltenberger Straße 694040 LinzAustria Max Planck Institute of Microstructure Physics Weinberg 206120 HalleSaaleGermany Soft Materials Lab Linz Institute of Technology LITJohannes Kepler University LinzAltenberger Straße 694040 LinzAustria Department of Soft Matter Physics Institute for Experimental PhysicsJohannes Kepler UniversityAltenberger Straße 694040 LinzAustria Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education Lanzhou University730000 LanzhouChina Faculty of Physics Adam Mickiewicz University61-614 PoznańPoland

In a spin-driven multiferroic system,the magnetoelectric coupling has the form of effective dynamical Dzyaloshinskii–Moriya(DM)***,it is confirmed,for instance,for Cu_(2)OSeO_(3),that the DM interaction has an essential role in the formation of skyrmions,which are topologically protected magnetic *** skyrmions are very robust and can be manipulated through an electric *** external electric field couples to the spin-driven ferroelectric polarization and the skyrmionic magnetic texture emerged due to the DM *** this work,we demonstrate the effect of optical *** a particular configuration of the external electric fields it is possible to trap or release the skyrmions in a highly controlled *** functionality of the proposed tweezer is visualized by micromagnetic simulations and model analysis.

关键词： interaction field instance

Magnetic field hyperactivity during the early Neoproterozoic: A paleomagnetic and cyclostratigraphic study of the Katav Formation, southern Urals, Russia

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Geoscience Frontiers 2023年第4期14卷 42-56页

作者： Inessa v.Golovanova Konstantin N.Danukalov Raushaniia Yu.Salmanova Natalia M.Levashova nikita P.Parfiriev Nina D.Sergeeva Joseph G.Meert Institute of Geology-Subdivision of the Ufa Federal Research Centre of the Russian Academy of Sciences(IG UFRC RAS) Russia Geological Institute Russian Academy of SciencesMoscowRussia Department of Earth and Planetary Sciences Neil Opdyke Paleomagnetic LaboratoryUniversity of FloridaGainesvilleFL 32611United States

We present a detailed magnetostratigraphic and cyclostratigraphic profile through the Riphean(Tonian)Katav Formation in the southern *** study confirms the primary nature of the magnetization in these *** cyclostratigraphic study identified several orbital periods including the 405 ka long *** allows us to quantify the reversal frequency in the Katav and our estimates range of 7–12 reversals per million *** on our study,we identify an interval of magnetic field reversal hyperactivity in the Neoproterozoic *** estimates for the Katav are contentious and range somewhere between 800 Ma and 900 Ma based on carbonate Pb-Pb ages and stable isotope *** paleomagnetic poles obtained in this study of the Katav(and overlying Inzer)Formation do not fit anywhere on the Baltica apparent polar wander path between 1100 Ma and 900 ***,they lie 90away from the 900 Ma segment of the *** tentatively estimate their age to be closer to 800 Ma and perhaps confirm a previously hypothesized pulse of rapid true polar wander between 825 Ma and 790 Ma.

关键词： Magnetostratigraphy Cyclostratigraphy Hyperactive reversal True polar wander Tonian

Alterations of morphology of lymphoid organs and peripheral blood indicators under the influence of gold nanoparticles in rats

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Journal of Innovative Optical Health Sciences 2016年第1期9卷 47-56页

作者： Alla B.Bucharskaya Svetlana S.Pakhomy Olga v.Zlobina Galina N.Maslyakova Olga v.Matveeva Irina O.Bugaeva nikita A.Navolokin Boris N.Khlebtsov vladimir A.Bogatyrev Nikolai G.Khlebtsov valery v.Tuchin Saratov State Medical University 112 B.Kazach'ya str.Saratov 410012Russia Institute of Biochemistry and Physiology of Plants and Microorganisms RAS 13 Entuziastov Prospekt.Saratov 410049Russia Saratov State University 83 Astrakhanskaya str.Saratov 410012Russia§Institute of Precise Mechanics and Control of Russian Academy of Sciences 24Rabochaya str.Saratov 410028Russia Interdisciplinary Laboratory of Biophotonics Tomsk State University 36 Lenina str.Tomsk 634050Russia

At present,gold nanoparticles(GNPs)are widely used in biomedical applications such as cancer diagnostics and ***,the potential toxicity hazards of these nanomaterials and human safety concerns are gaining significant ***,we report the effects of prolonged peroral administration of GNPs with different sizes(2,15 and 50 nm)on morphological changes in lymphoid organs and indicators of peripheral blood of laboratory *** experiment was conducted on 24 white mongrel male rats weighing 180–220 g,gold nanospheres sizes 2,15 and 50nm were administered orally for 15 days at a dosage of 190g/kg of animal body *** GNPs were conjugated with polyethylene glycol to increase their biocompatibility and *** size-dependent decrease of the number of neutrophils and lymphocytes was noted in the study of peripheral blood,especially pronounced after administration of GNPs with size of 50 *** stimulation of myelocytic germ of hematopoiesis was recorded at morphological study of the bone *** signs of strengthening of the processes of differentiation and maturation of cellular elements were found in lymph nodes,which were showed as the increasing number of immunoblasts and large *** quantitative changes of cellular component morphology of lymphoid organs due to activation of migration,proliferation and di®erentiation of immune cells indicate the presence of immunostimulation effect of GNPs.

关键词： Gold nanoparticles lymphoid organs morphological changes bone marrow examination