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Energy & Environmental Materials 2023年第4期6卷 6-14页

作者： Mohit Saraf Christopher E.Shuck Nazgol Norouzi Kyle Matthews Alex Inman Teng Zhang ekaterina Pomerantseva Yury Gogotsi A.J.Drexel Nanomaterials Institute and Department of Materials Science and Engineering Drexel UniversityPhiladelphia PA 19104USA

While transition-metal oxides such as α-MoO_(3)provide high capacity,their use is limited by modest electronic conductivity and electrochemical instability in aqueous ***-dimensional(2D)MXenes,offer metallic conductivity,but their capacitance is limited in aqueous *** of partially solvated cations into Ti_(3)C_(2)MXene from lithium-based water-in-salt(WIS)electrolytes enables charge storage at positive potentials,allowing a wider potential window and higher ***,we demonstrate that α-MoO_(3)/Ti_(3)C_(2)hybrids combine the high capacity of α-MoO_(3)and conductivity of Ti_(3)C_(2)in WIS(19.8 m LiCI)electrolyte in a wide1.8 v voltage *** voltammograms reveal multiple redox peaks from α-MoO_(3)in addition to the well-separated peaks of Ti_(3)C_(2)in the hybrid *** leads to a higher specific charge and a higher rate capability compared to a carbon and binder containing α-MoO_(3)*** results demonstrate that the addition of MXene to less conductive oxides eliminates the need for conductive carbon additives and binders,leads to a larger amount of charge stored,and increases redox capacity at higher *** addition,MXene encapsulated α-MoO_(3)showed improved electrochemical stability,which was attributed to the suppressed dissolution of α-MoO_(3).The work suggests that oxide/MXene hybrids are promising for energy storage.

关键词： free-standing electrode Ti_(3)C_(2)MXene water-in-salt electrolytes α-MoO_(3)nanobelts

Generation of dual and quad‑optical frequency combs in the injected radiation free mode‑locked frequency‑shifted feedback laser

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Frontiers of Optoelectronics 2023年第3期16卷 43-56页

作者： Sergey N.Mantsevich ekaterina I.Kostyleva Andrey N.Danilin vladimir S.Khorkin Physics Department M.V.Lomonosov Moscow State UniversityMoscow 119991Russia Russian Quantum Center(RQC) Skolkovo 143026Russia

The results of an optoelectronic system—frequency-shifted feedback(FSF)laser experimental examination are *** considered FSF laser is seeded only with optical amplifer spontaneous emission(ASE)and operates in the mode-locked regime,whereby the output radiation is sequence of short pulses with a repetition rate determined by the delay time in its optical feedback *** the frequency domain,the spectrum of such a pulse sequence is an optical frequency comb(OFC).These OFCs we call *** consider the possibility of tunable acousto-optic(AO)dual and quad-comb frequency spacing downconversion in the FSF laser seeded with ASE and operating in the mode-locked *** examined system applies a single frequency shifting loop with single AO tunable flter as the frequency shifter that is fed with several radio frequency signals *** initial OFCs with frequency spacing of about 6.5 MHz may be obtained in the wide spectral range and their width,envelope shape and position in the optical spectrum may be *** dual-combs are obtained with a pair of initial OFCs aroused by two various ultrasound waves in the acousto-optic tunable flter(AOTF).The dual-combs frequency spacing is determined by the frequency diference of the signals applied to the AOTF piezoelectric transducer and can be tuned *** quad-combs are obtained with three initial OFCs,forming a pair of dual-combs,appearing when three ultrasound frequencies feed the AOTF *** quad-combs frequency spacing is defned by the diference between the frequency spacing of ***-combs with more than 5000 spectral lines and tunable frequency spacing are *** successive frequency downconversion gives the possibility to reduce the OFC frequency spacing form several MHz for initial OFC to tens of kHz for quad-combs.

关键词： Frequency-shifted feedback laser Optical frequency combs Acousto-optics Dual-combs Quad-combs

The Influence of Ceric Oxide on Phase Composition and Activity of Iron Oxide Catalysts

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Advances in Chemical Engineering and Science 2012年第1期2卷 28-33页

作者： Aleksandr A. Lamberov ekaterina v. Dementyeva Dmitriy I. vavilov Olga v. Kuzmina Rinat R. Gilmullin ekaterina A. Pavlova 不详

The process of dehydrogenation of methyl butenes to isoprene is conducted in the presence of iron oxide catalysts whose composition may include oxides of alkaline metals, alkaline earth metals, and transition metals. Catalysts of latest generation can also contain oxides of rare earth elements, particularly cerium oxide. However there is no any common opinion concerning its effect on catalytic properties of iron oxide catalysts. It is well known that ceric oxide has a positive effect on the quantity and stability of active centers and can play a critical role in a redox cycle of the dehydrogenation process. By means of differential thermal analysis, dispersion analysis and X-ray phase analysis, it was found in present study that introducing of ceric oxide promotes the decrease in hematite crystallite sizes. At the same time, it prevents potassium polyferrites formation, with the equilibrium of topochemical reaction between ferric oxide and po tassium carbonates moving predominantly to the formation of intermediate products–monoferrite systems, having greater catalytic activity. The increase in potassium monoferrite content results in dispersion of particles in the Fe2O3-K2CO3-СеО2 system that is accompanied by modification of texture characteristics. For this catalyst composition, the optimum concentration of ceric oxide (8.7 wt.%), leading to the formation of a certain ratio of mono- and polyferrite phases, was found. If more than 8.7 wt.% of СеО2 is introduced, the modification of texture characteristics of catalyst samples takes place, that negatively affects their selectivity.

关键词： Process of Dehydrogenation Ferric Oxide Ceric Oxide Monoferrite and Polyferrite Systems

Cartographic Approach in Studying Landscape Northwestern of Part Western Siberia

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American Journal of Plant Sciences 2015年第13期6卷 2177-2184页

作者： ekaterina Kuzmenko Institute of geography Russian Academy of Sciences Siberian Branch Irkutsk Russia

The structure and dynamics of geosystems: plant of forest and bogs in the northwestern part of Western Siberia is considered by using the Kazym-Lyamin interfluve, based on the landscape-assessment map for the middle part of the Khanty-Mansi Autonomous District. The study used the landscape structural-dynamical approach and the methods of studying the spatio-temporal dynamics of taiga geosystems. Theoretical and methodological research on the development of the landscape-assessment map for Asian Russia is high on the cartographic agenda of the v. B. Sochava Institute of geography SB RAS. The methodic research is to be used to Landsat-5 TM in GIS Multi-Spec and Qgis. An analysis is also made of the topographic, geomorphologic and forest 1:200,000 maps, the profiles characterize the lithology, field data of geobotanical and soil descriptions, and experimental permanent station operated. The landscape structure of this area and its hierarchical subordination are represented in the map legend in terms of groups of facies which are combined into regional-typological classification units: groups of geoms, classes, and types of natural environment. Landscape mapping and planning will help to timely prevent and forecast the magnitudes of disturbances to natural environment using and be as the basis for a package of optimal nature-conservation measures and target-oriented technogenic and anthropogenic impacts.

关键词： Geosystems Landscape Map Successional Dynamics Plant

A rened analytical model for reconstruction problems in diuse reectance spectroscopy

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Journal of Innovative Optical Health Sciences 2024年第5期17卷 33-51页

作者： ekaterina Sergeeva Daria Kurakina Ilya Turchin and Mikhail Kirillin A.v.gaponov-grekhov institute of applied physics of the russian academy of sciences ulyanov st.46 603950nizhny novgorodrussia

A rened analytical model of spatially resolved diffuse reectance with small source-detector separations(SDSs)for the in vivo skin studies is *** to the conventional model developed by Farrell et al.,it accounts for the limited acceptance angle of the *** rened model is validated in the wide range of optical parameters by Monte Carlo simulations of skin diffuse reectance at SDSs of units of *** of uniform dermis and two-layered epidermis-dermis structures are *** accuracy of the rened model compared to the conventional one is demonstrated in the separate,constraint-free reconstruction of absorption and reduced scattering spectra of uniform dermis from the Monte Carlo simulated *** the case of epidermis-dermis geometry,the recovered values of reduced scattering in dermis are overestimated and the recovered values of absorption are underestimated for both analytical ***,in the presence of a thin mismatched topical layer,only the effective attenuation coe±cient of the bottom layer can be accurately recovered using a diffusion theorybased analytical model while separate reconstruction of absorption and reduced scattering fails due to the inapplicability of the method of ***-ndings require implementation of more sophisticated models of light transfer in inhomogeneous media in the recovery algorithms.

关键词： Diffuse reffectance spectroscopy in vivo skin studies optical properties reconstruction diffuse approximation Monte Carlo simulations method of images

Impact of postoperative TNM stages after neoadjuvant therapy on prognosis of adenocarcinoma of the gastro-oesophageal junction tumours

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World Journal of Gastroenterology 2018年第13期24卷 1429-1439页

作者： Michael Thomaschewski Richard Hummel ekaterina Petrova Juliana Knief Ulrich Friedrich Wellner Tobias Keck Dirk Bausch Department of Surgery University Medical Center Schleswig-Holstein Campus Lübeck Department of Pathology University Medical Center Schleswig-Holstein Campus Lübeck

AIM To compare prognostic relevance of postoperative tumour/node/metastasis(TMN) stages between patients with and without neoadjuvant treatment. METHODS Data from patients with adenocarcinoma of the gastrooesophageal junction(AEG) who had undergone surgical resection at a single German university centre were retrospectively analysed. Patients with or without neoadjuvant preoperative treatment were selected by exact matching based on preoperative staging. Standard assessment of preoperative(c)TNM stage was based on endoscopic ultrasound and computed tomography of the thorax and abdomen, according to the American Joint Committee on Cancer/Union for International Cancer Control classification system. Patients with cT1cN0cM0 and cT2cN0cM0 stages were excluded from the study, as these patients are generally not recommended for pretreatment. Longterm survival among the various postoperative TNM stages was compared between the groups of patients with or without neoadjuvant treatment. For statistical assessments, a P-value of ≤ 0.05 was considered *** The study included a total of 174 patients. The group of patients who had received preoperative neoadjuvant treatment included more cases of AEG(Siewert) type 1 carcinoma(P ve neoadjuvant treatment) had comparable preoperative T stages, but the group of patients with preoperative neoadjuvant treatment presented a higher rate of preoperative N-positive disease(P = 0.020). Overall long-term survival was not different between the two groups of patients according to tumours of different AEG classifications, receipt of oesophagectomy or gastrectomy, nor between patients with similar postoperative TNM stage, resection margin and grading. However, an improvement of long-term survival was found for patients with nodal down-staging after neoadjuvant therapy(P = 0.053).CONCLUSI

关键词： Adenocarcinoma of the gastro-oesophageal junction American Joint Committee on Cancer/Union for International Cancer Control TNM system Neoadjuvant therapy Oesophageal cancer

Reversion of Incommensurate Modulation in Cubic Lazurite: Example of Reversible Forced Equilibrium?

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Natural Resources 2014年第12期5卷 761-771页

作者： vladimir L. Tauson Anatoly N. Sapozhnikov ekaterina v. Kaneva Sergei v. Lipko A. P. vinogradov Institute of Geochemistry Siberian Branch of the Russian Academy of Sciences Irkutsk Russia

The sample of cubic lazurite, collected in the Baikal region, with incommensurately 3D modulated (ITM) structure has been studied by the method of high-temperature X-ray powder diffraction. At short time of annealing in high-temperature diffraction experiment the modulation recovery proceeds during cooling down the sample to room temperature. The identity of the period of both initial and recovered modulation demonstrates that the system has a structural memory. The acquired results are interpreted through comparison of thermal behavior of lazurite, sodalite and quartz structures. It is supposed that two kinetically different and thermally activated processes proceed under heating: 1) reversible framework expansion due to Si-O-Al angle increase, and 2) equalizing of periodic local distortions via the diffusion-controlled transfer of cage ions between adjacent subcells. The second process seems to be much slower than the first one, especially at lower temperatures. With increasing temperature, both processes are activated. However, the framework expands more rapidly than the cage clusters migrate, and the periodic distortions of the framework are aligned. Under lower temperatures, the framework shrinks and again accommodates to the configuration of cage cations (clusters), which may be changed at high temperature and sufficient time or may not at lower temperature, short time, unfavorable SO2 fugacity values. In the first case the modulation disappears entirely, while in the second case it arises again. The probable reason for ITM formation is the balance of counteracting energetic terms: the elastic strain energy of structure deformation and the energy of cluster ordering providing the state of forced equilibrium. The excess free energy due to structure distortion is compensated by the increment associated with the cluster ordering process. However, no significant variations in sulphur anion speciation for different degrees of modulation retention were observed by X

关键词： Lazurite High-Temperature X-Ray Diffraction Incommensurate Modulation Reversion Mechanism Forced Equilibrium Sulphur Speciation

西西伯利亚东南部早凡兰吟期孢粉地层学，古环境和植被再造

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地层学杂志 2012年第2期36卷 179-192页

作者： ekaterina B.PESTCHEvITSKAYA Irina v.SMOKOTINA Galina E.BAYKALOvA 俄罗斯西伯利亚石油地质与地球物理研究所俄罗斯新西伯利亚630090 克拉斯诺沃茨克地质调查所俄罗斯克拉斯诺亚尔斯克660020

分析了西西伯利亚东南地区的下凡兰吟阶的两个剖面的陆相孢粉型化石的分布。依据西伯利亚北部已经定年的剖面中动物群建立起来的孢粉组合的对比,确定了孢粉标志层的定义,并与北方区的菊石带相对应的孢粉组合进行了对比。这一工作为早凡... 详细信息

分析了西西伯利亚东南地区的下凡兰吟阶的两个剖面的陆相孢粉型化石的分布。依据西伯利亚北部已经定年的剖面中动物群建立起来的孢粉组合的对比,确定了孢粉标志层的定义,并与北方区的菊石带相对应的孢粉组合进行了对比。这一工作为早凡兰吟期与气候变化息息相关的植被和景观的短期变化以及周边古盆地变迁的重建,提供了地层依据。欧亚大陆中部和东部地区凡兰吟期孢粉组合的横向对比显示:西西伯利亚东南地区的植被具有印度欧洲和西伯利亚加拿大两大古植物地理区的过渡性质,显有这两区的典型特征。

关键词：孢粉地层学古植物古植物区凡兰吟期白垩纪西西伯利亚

Effect of Zr^(4+)on piezoelectric,dielectric and ferroelectric properties of barium calcium titanate lead-free ceramics

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Journal of Advanced Dielectrics 2021年第6期11卷 23-31页

作者： Prasanta Kumar Panda Benudhar Sahoo v.Sureshkumar ekaterina Dmitrievna Politova Materials Science Division CSIR-National Aerospace Laboratories KodihalliBengaluru 560017India Semenov Federal Research Centre for Chemical Physics Russian Academy of Sciences Kosygin 4Moscow 119991Russia

Ba_(0.85)Ca_(0.15)(Ti1−xZrx)O_(3)(BCTZ)ceramics with x=0.05,0.10,_(0.15),0.20,0.25,0.30 were prepared by the solid-state reaction *** of the powders was carried out at 1100°C for 4 h and the green pellets were sintered at 1400°C for 2 h.X-ray diffraction patterns of the sintered pellets showed tetragonal splitting up to x=0.10 while the mixture of the rhombohedral/cubic phase appeared at higher ZrO_(2)*** piezoelectric charge constant d33=510 pC/N and strain(S=0.103%)were measured for BCT doped by 0.10 mol ZrO_(2).Dielectric constant,remnant polarization and saturation polarization also found maxima for this *** Curie temperature(TC)of the compositions decreased with increase in ZrO_(2)concentration and reached 98°C,87°C and 36°C at x=0.05,0.10,_(0.15)mol,*** remaining compositions have TC below the room temperature;therefore,they can be used for subzero/cryogenic *** scanning electron microscopy study revealed an increase in grain size with increase in ZrO_(2)concentration and confirmed the complete solubility of ZrO_(2)in the crystal ***,low ZrO_(2)-doped BCT compositions with high d33 could be suitable for low temperature(<80°C)applications.

关键词： ZrO_(2)-doped BCT lead-free piezoelectrics high piezoelectric charge constant Curie temperature