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Highly efficient photo-thermal synergistic catalysis of CO_(2)methanation over la_(1-x)Ce_(x)NiO_(3)perovskite-catalyst

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Nano Research 2024年第9期17卷 7945-7956页

作者： Ting li Zhen-yu Zhang De-Cun luo Bo-yu Xu Rong-Jiang Zhang Ji-long Yao Dan li Tao Xie Institute of Industrial Catalysis School of Chemical Engineering and TechnologyXi’an Jiaotong UniversityXi’an 710049China

solar-driven photo-thermal catalytic CO_(2)methanation reaction is a promising technology to alleviate the problems posed by greenhouse gases ***,designing advanced photo-thermal catalysts remains a research challenge for CO_(2)methanation *** this work,a series of ABO3(A=lanthanide,B=transition metal)perovskite catalysts with Ce-substituted laNiO3(la_(1-x)Ce_(x)NiO_(3),x=0,0.2,0.5,0.8,1)were synthesized for CO_(2)*** la_(0.2)Ce_(0.8)NiO_(3) exhibited the highest CH_(4) formation rate of 258.9 mmol·g^(-1)·hcat-1,CO_(2)conversion of 55.4%and 97.2%CH_(4) selectivity at 300℃with the light intensity of 2.9 W·cm^(-2).Then the catalysts were thoroughly analyzed by physicochemical structure and optical properties *** partial substitution of the A-site provided more active sites for the adsorption and activation of CO_(2)/H_(2).The sources of the active sites were considered to be the oxygen vacancies(O_(v))created by lattice distortions due to different species of ions(la^(3+),Ce^(4+),Ce^(3+))and exsolved Ni0 by H_(2)*** catalysts have excellent light absorption absorbance and low electron-hole(e^(-)/h^(+))recombination rate,which greatly contribute to the excellent performance in photo-thermal synergistic catalysis(PTC)CO_(2)*** results of in situ irradiated electron paramagnetic resonance spectrometer(IsI-EPR)and IsI-X-ray photoelectron spectroscopy(XPs)indicated that the aggregation of unpaired electrons near the defects and Ni metal(from la and Ce ions to ov and Ni0)accelerated adsorption and activation of CO_(2)/H_(2).At last,the catalyst properties and structure were correlated with the proposed reaction mechanism from the in situ diffuse reflection infrared Fourier transform spectrum(DRIFTs)*** in situ precipitation of the B-site enhanced the dispersion of Ni,while its enriched photoelectrons upon illumination further promote hydrogen *** H^(*)spillover accelerated t

关键词： photo-thermal catalysis CO_(2)methanation perovskite A-site substitution in situ diffuse reflection infrared Fourier transform spectrum(DRIFTs)

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Influence of oxygen non-stoichiometry on physical properties of Ndsr_2Mn_2O_(7±δ)

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Journal of Rare Earths 2015年第3期33卷 282-288页

作者： A.M.Yankin A.v.Fetisov O.M.Fedorova s.A.Uporov v.Ya.Mitrofanov laboratory of static and Kinetics of Processes Institute of Metallurgy of Ural Branсh of Russian Academy of Science Amundsen St. 101 Ekaterinburg 620016 Russia

Nd sr2Mn2O7＋δ compounds were synthesized by ceramic method under three different cooling conditions. The Nd sr2Mn2O7＋δ samples were characterized by powder X-ray diffraction（XRD）. Oxygen non-stoichiometry data for the studied powders were determined by using gravimetric and X-ray photoelectron spectroscopy（XPs） methods. The correlation of cooling method and oxygen as non-stoichiometry was established. The electroconductivity in samples was studied by using four-point probe method, and the strong correlation with non-stoichiometry was found out. Magnetization measurements were carried out. It was found that the magnetic and transport properties of the samples were also influenced by oxygen non-stoichiometry. The evolution of the magnetic properties could be explained by the formation of magnetic clusters in the vicinity of oxygen vacancies（ov） and strong competition between the superexchange and double exchange interactions.

关键词： oxygen stoichiometry gravimetric analysis electroconductivity magnetic properties rare earths

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long-term survival of a patient after resection of a gastrointestinal stromal tumor arising from the pancreas

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Hepatobiliary & Pancreatic Diseases International 2011年第3期10卷 330-332页

作者： Filip eka Bohumil Jon Alexander Ferko Zdeněk ubrt Dimitar H Nikolov věra Tyová Department of surgery Faculty of Medicine and University Hospital Hradec Králové Department of Field surgery Military Health Science FacultyHradec KrálovéDefence University Brno Fingerland Department of Pathology

BACKGROUND:Gastrointestinal stromal tumors (GIsTs) may arise in any part of the gastrointestinal tract;extragastrointestinal locations are extremely *** a few cases of extragastrointestinal stromal tumor arising from the pancreas were *** of the reports described a long-term follow-up of the ***:This report describes an interesting and unusual case of GIsT arising from the ***:A 74-year-old female presented with a palpable abdominal *** scan showed a large mass 11×8×4 cm originating from the tail of the *** biopsy revealed a GIsT predominantly with spindle cells,but some parts also contained epitheloid *** patient was treated by distal pancreatic resection with *** of the tumor showed a staining pattern characteristic of *** patient has achieved a long-term survival of five years and six months without any sign of recurrence of the ***:This is the first reported case of an extragastrointestinal stromal tumor arising from the pancreas treated surgically,with a long-term survival.

关键词： gastrointestinal stromal tumor pancreas survival

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A COMPREHENsIvE sTUDY OF FRETTING FATIGUE OF sTRUCTURAl AllOYs IN sYMMETRIC TENsION-COMPREssION

A COMPREHENSIVE STUDY OF FRETTING FATIGUE OF STRUCTURAL ALLO...

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第三届摩擦疲劳学国际会议

作者： G.v. TsYBAN’ov yu. KURAsH Institute for Problems of strength National Academy of sciences of Ukraine 2 Timiryazevskaya str. Kiev-14 01014 Ukraine Institute for Problems of strength National Academy of sciences of Ukraine 2 Timiryazevskaya str. Kiev-14 01014 Ukraine

＜正＞A method of fatigue testing is proposed for fretting pairs of structural alloys. The distinctive feature of the method is a possibility of measuring and controlling contact pressure, friction forces, and sliding amplitudes using electric signals with a subsequent preliminary processing, filtering and accumulation of the tests results in a computer. The authors justify the use of the value of electrie microcurrents occurring in the fretting pair in the course of testing as a parameter for the evaluation of the level of damaging processes of nonmechanical nature.

关键词： Fretting fatigue Damaging processes Tribocurrents Data processing

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Deficiency of Adenomatous Polyposis Coli protein in sporadic colorectal adenomas and its associations with clinical phenotype and histology

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World Journal of Gastroenterology 2006年第24期12卷 3901-3905页

作者： Martin Bortlík Ivana vítková Martina Pape(z|ˇ)ová Milada Kohoutová Ale(s|ˇ) Novotn(y|') stanislav Adamec Petra Chalupná Milan luká(s|ˇ) Gastroenterology Center 4th Internal Department General Faculty Hospital1st School of MedicineCharles UniversityPragueCzech Republic Department of Pathology General Faculty Hospital 1st School of MedicineCharles UniversityPragueCzech Republic Institute for Biology and Medical Genetics General Faculty Hospital 1st School of MedicineCharles UniversityPragueCzech Republic

AIM： To evaluate the frequency of the loss of the Adenomatous Polyposis Coil （APC） protein and to compare the APC status with the characteristics of colorectal adenomas. METHODs： Immunohistochemical analysis of the APC protein was performed on 118 adenomas and the results were compared with parameters of malignant potential, location of adenomas, macroscopic appearance and age of the patients. REsUlTs： A complete loss of the APC protein was found in 28 （24%） adenomas, while 90 （76%） were APC positive. The mean size of adenomas was 13.5± 14.2 mm （95% CI 10.5-16.5） in APC-positive, and 13.8 ±15.5 mm （95% CI 7.8-19.8） in APC-negative adenomas （P = 0.364）. statistical analysis revealed no difference between APC-positive and negative adenomas as to the histological type （P = 0.327） and grade of dysplasia （P =0.494）. We found that even advanced adenomas did not differ in their APC status from the non-advanced tumors （P = 0.414）. Finally, no difference was found when the location （P = 0.157）, macroscopic appearance （P = 0.571） and age of patients （P = 0.438） were analysed and compared between both APC positive and negative adenomas. CONClUsION： Most adenomas expressed full-length APC protein, suggesting that protein expression is not a reliable marker for assessment of APC gene mutation. Complete loss of APC protein did not influence morphology, location, or appearance of adenomas, nor was it affected by the patient＇s age.

关键词： Adenomatous Polyposis Coli protein Adeno-ma Immunohistochemistry Histology

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时滞系统控制算法的改进

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基础自动化 2000年第6期7卷 9-10,39页

作者：韩绍坤 Nоviкov v.А . 北京理工大学北京100081 st.Petersburg ETU russia197396

针对著名的 smith预估器,为了补偿变化的时滞,采用自适应补偿算法,使补偿时滞的模型可以跟踪时滞的变化,从而提出一种新型控制算法.仿真结果表明,改进的方案可以明显地提高控制系统精度.

关键词：时滞系统控制算法 smith预估器自适应控制

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Analysis of Higher Order system with Impulse Exciting Functions in Z-Domain

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Circuits and systems 2016年第11期7卷 3951-3970页

作者： Branislav Dobrucký Pavol Štefanec Mariana Beňová Oleg v. Chernoyarov Michal Pokorný Faculty of Electrical Engineering University of ?ilina ?ilina Slovak Republic Department of Radio Engineering Devices and Antenna systems National Research University Moscow Power Engineering Institute Moscow Russia

This paper deals with mathematical modelling of impulse waveforms and impulse switching functions used in electrical engineering. Impulse switching functions are later investigated using direct and inverse z-transformation. The results make possible to present those functions as infinite series expressed in pure numerical, exponential or trigonometric forms. The main advantage of used approach is the possibility to calculate investigated variables directly in any instant of time;dynamic state can be solved with the step of sequences (T/6, T/12) that means very fast. Theoretically derived waveforms are compared with simulation worked-out results as well as results of circuit emulator lT spice which are given in the paper.

关键词： Impulse systems switching Function Z-Transformation Inverse Z-Transformation steady state Operation Dynamical state Model Modelling and simulation

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Diversity of foliar endophytes in wind-fallen Picea abies trees

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Fungal Diversity 2012年第3期54卷 69-77页

作者： Ondřej Koukol Miroslav Kolařík Zuzana Kolářová Petr Baldrian Department of Botany Faculty of ScienceCharles University in PragueBenátská212801 Prague 2Czech Republic laboratory of Genetics Physiology and Bioengineering of FungiInstitute of Microbiology of the ASCRv.v.i.Vídeňská108314220 Prague 4Czech Republic laboratory of Environmental Microbiology Institute of Microbiology of the ASCRv.v.i.Vídeňská108314220 Prague 4Czech Republic

The unmanaged Norway spruce montane forests in the Bohemian Forest National Park(Czech Republic)suffered from repeated large-scale bark beetle outbreaks in last *** this study,the diversity of culturable foliar endophyte microfungi in needles originating from eleven recently wind-fallen trees in this area was *** aims were to describe their diversity and to determine the relative host and organ specificities of isolated endophyte species to estimate the species pool and abundance of foliar endophytes before the forest *** were isolated from surface-sterilized needles,and the outgrowing strains were identified based on morphological and molecular characteristics(analyses of ITs1,ITs2 and partial 28s rDNA).Fungal communities in the needles were diverse,with ascomycetes(mostly anamorphs of Helotiales)dominating *** most frequent species(Phacidiopycnis sp.,Cistella acuum,sirococcus *** two species of Chalara)did not correspond with those recorded in previous studies of Picea *** example,the widely distributed lophodermium piceae was rarely recorded in this *** pattern may be caused by different methods of sterilization and cultivation or by physiological characteristics of the needles,or it may reflect the species distribution in the studied *** of the Helotiales,along with sequences from GenBank,showed substantial overlap in host affinities,most prominently between Pinus and Picea,and also among species from distant plant lineages.

关键词： Morphospecies ITs rDNA Culturable microfungi Phacidiopycnis Host affinity

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Evaluation of natural forest regeneration as a part of land restoration in the Khentii massif,Mongolia

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Journal of Forestry Research 2020年第5期31卷 1773-1786页

作者： David Juricka Antonın Kusbach Jana Parılkova Jakub Houska Pavlına Ambrozova vaclav Pecina Zdena Rosicka Martin Brtnicky Jindrich Kynicky Department of Geology and Pedology Faculty of Forestry and Wood TechnologyMendel UniversityZemedelska 161300 BrnoCzech Republic Department of Forest Botany Dendrology and GeobiocoenologyFaculty of Forestry and Wood TechnologyMendel UniversityZemedelska161300 BrnoCzech Republic Faculty of Civil Engineering Institute of Water StructuresBrno University of TechnologyZizkova 1760200 BrnoCzech Republic Central European Institute of Technology Brno University of TechnologyPurkynova 656/12361200 BrnoCzech Republic

Forest stands in the semi-arid environment of northern Mongolia have an essential role in controlling ongoing desertification in the surrounding *** the last decade,the total forest area has decreased *** aim of this study was to evaluate the potential of natural regeneration as an essential element for ensuring sustainability of these *** on field measurements from 120 plots in six sites,our assessment tool revealed five qualitative categories of forest regeneration,allowing us to assess impacts of both grazing and environmental conditions on the regeneration *** is a crucial factor and adversely affects *** sites with relatively low grazing intensity,low soil moisture levels represent the main reason for reduced *** approach to classification proposed in this study allows for the identification and interpretation of stand conditions where natural regeneration has *** study provides an important foundation to inform decisionmaking related to land protection and restoration *** findings could be used in comparative studies and,importantly,may aid further mapping of Mongolian forests.

关键词： Mongolia Natural forest regeneration seedlings larix sibirica land restoration Desertification

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vertex-antimagic labelings of Regular Graphs

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Acta Mathematica sinica,English series 2012年第9期28卷 1865-1874页

作者： Ali AHMAD Kashif AlI Martin BACA Petr KovAR Andrea sEMANICovA-FENovCíKovA College of Computer science and Information systems Jazan University Faculty of Mathematics COMSATS Institute of Information Technology Department of Applied Mathematics and Informatics Technical University Department of Applied Mathematics VB-Technical University of Ostrava

let G = （v, E） be a finite, simple and undirected graph with p vertices and q edges. An （a, d）-vertex-antimagic total labeling of G is a bijection f from v（G） t2 E（G） onto the set of consecutive integers 1, 2,... ,p ＋ q, such that the vertex-weights form an arithmetic progression with the initial term a and difference d, where the vertex-weight of x is the sum of the value f（x） assigned to the vertex x together with all values f（xy） assigned to edges xy incident to x. such labeling is called super if the smallest possible labels appear on the vertices. In this paper, we study the properties of such labelings and examine their existence for 2r-regular graphs when the difference d is 0, 1,..., r ＋ 1.

关键词： super vertex-antimagic total labeling vertex-antimagic edge labeling regular graph

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