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Synthesis of Catalytic Systems Based on Nanocomposites Containing Palladium and Hydroxycarbonates of Rare-Earth Elements

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贵金属 2012年第A1期33卷 76-78页

作者： GALANtSEv. M. v. BUSLAEv. t. M. PAKKANEN t. FOMICHEv.v. v. MISCHIHINA E. A. Moscow State Univ.rsity of Fine Chemical technologies named after M.v. Lomonosov.(MItHt named after M.v. Lomonosov. Moscow Russia Univ.rsity of Eastern Finland (UEF) Joensuu Finland.

the purpose of this work is to synthesize the catalytic systems containing palladium nanoparticles and using hydroxycarbonates of yttrium and cerium as supports,and to test the catalytic activ.ty of the obtained catalysts in the Suzuki cross-couping *** Pd/Y(OH)CO 3 and Pd/Ce(OH)CO 3 were synthesized according to two methods:the first one-simultaneous production of nanoscale substrate and immobilization of palladium nanoparticles on its surface(nanocomposites 1),the second one-the prior synthesis of polyv.nylpyrrolidone stabilized palladium nanoparticles followed by their immobilization on the nano sized substrate surface(nanocomposites 2).the reaction between phenylboronic acid and iodobenzene is chosen as a model *** dependence of the catalytic activ.ty of catalysts on the method of their synthesis was *** was established that nanocomposites 2 exhibit higher catalytic activ.ty in the selected reaction compared to the nanocomposites *** tOF v.lues for the nanocomposites 1 are 6663～14617 h 1 when using the substrate Ce(OH)CO 3 and 13774～27084 h 1 when using the substrate Y(OH)CO 3,while the nanocomposites 2 rev.al tOF = 87287 h 1 for the substrate Ce(OH)CO 3 and tOF = 97746 h 1 for the substrate Y(OH)CO 3 under other equal *** addition,nanocomposites 2 "work" at room temperature giv.ng a high yield of the desired *** is noted that the support nanoparticles Y(OH)CO 3 and Ce(OH)CO 3 also exhibit catalytic *** yield of the final product of the reaction using them as catalysts is 55%(tOF = 11 and 8 h 1,respectiv.ly).thus,the use of yttrium and cerium hydroxycarbonates as supports allows to decrease the palladium content in the nanocomposites to 0.01%～1% and,consequently,reduce the cost of the catalyst while maintaining its high catalytic activ.ty.

关键词： palladium nanoparticles support Y(OH)CO3 Ce(OH)CO3 nanocomposites Suzuki reaction catalytic activ.ty

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Experimental isothermal section phase diagram of Ho-Fe-In at 773 K and magnetic properties of Ho_(12)Fe_(2.08)In_(2.92) alloy

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Rare Metals 2021年第4期40卷 987-994页

作者： Xiang Chen Chao ni the College of Physics and Electronic Information Engineering Neijiang Normal UniversityNeijiang 641002China the Ames Laboratory U.S.Department of EnergyIowa State UniversityAmesIA 50011-3020USA

the isothermal section of the Ho-Fe-In system at 773 K has been constructed by X-ray powder *** known structure ternary compound Er_(12)Fe_(2) In_(3)-type Ho_(12)Fe_(2) In_(3) has been *** the same time,solid solutions are not detected in Ho-Fe-In system at 773 *** magnetic transition and magnetocaloric effect of Ho_(12)Fe_(2.08)In_(2.92) alloy with Er_(12)Fe_(2) In_(3)-type structure were inv.stigated by magnetic susceptibility and isothermal magnetization *** normal antiferromagnetic-paramagnetic transition and another abnormal one are discov.red at 18 and 76 K in ground state,*** to a first-order field-induced metamagnetic transition(antiferromagnetic-ferromagnetic) at/below the Neel temperature of 18 K),the negativ. entropy changes are observ.d at corresponding *** is only a second-order ferromagnetic-paramagnetic transition near Curie temperature(tC),the maximum entropy change(Δ_(Smax)) v.lues are-6.14 J·kg^(-1)·K^(-1) at 3 K and 7.88 J·kg^(-1)·K^(-1) at 28 K in a field range of 0-7 *** rev.rsible relativ. cooling power corresponding to negativ. entropy change can reach about 600 J·kg^(-1) in an wide operating temperature region Δ_(tcycl)=74 K from 16 to90 K,which suggests that Ho_(12)Fe_(2.08)In_(2.92) could be a potential material for magnetic refrigeration in the corresponding temperature range.

关键词： Re_(3(x+y))(t2)_(x)X_(y)phase Metamagnetic transition Magnetothermal properties Ho-Fe-In alloy

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Irritable bowel syndrome:A clinical rev.ew

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World Journal of Gastroenterology 2014年第34期20卷 12144-12160页

作者： Rosa ls Soares Internal Medicine Department Faculty of MedicineFederal Fluminense UniversityRio de Janeiro 24030-210Brazil

Irritable bowel syndrome (IBS) remains a clinical challenge in the 21st century. It’s the most commonly diagnosed gastrointestinal condition and also the most common reason for referral to gastroenterology clinics. Its can affect up to one in fiv. people at some point in their liv.s, and has a significantly impact of life quality and health care utilization. the prev.lence v.ries according to country and criteria used to define IBS. v.rious mechanisms and theories hav. been proposed about its etiology, but the biopsychosocial model is the most currently accepted for IBS. the complex of symptoms would be the result of the interaction between psychological, behav.oral, psychosocial and env.ronmental factors. the diagnosis of IBS is not confirmed by a specific test or structural abnormality. It is made using criteria based on clinical symptoms such as Rome criteria, unless the symptoms are thought to be atypical. today the Rome Criteria III is the current gold-standard for the diagnoses of IBS. Secure positiv. ev.dence of IBS by means of specific disease marker is currently not possible and cannot be currently recommended for routine diagnosis. there is still no clinical ev.dence to recommend the use of biomarkers in blood to diagnose IBS. Howev.r, a number of different changes in IBS patients were demonstrated in recent years, some of which can be used in the future as a diagnostic support. IBS has no definitiv. treatment but could be controlled by non-pharmacologic management eliminating of some exacerbating factors such certain drugs, stressor conditions and changes in dietary *** traditional pharmacologic management of IBS has been symptom based and sev.ral drugs hav. been used. Howev.r, the cornerstone of its therapy is a solid patient physician relationship. this rev.ew will prov.de a summary of pathophysiology, diagnostic criteria and current and emerging therapies for IBS.

关键词： Irritable bowel syndrome Clinical rev.ew Pathogenesis Diagnostic treatment Biopsychosocial model

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Dehydration at subduction zones and the geochemistry of slab fluids

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Science China Earth Sciences 2020年第12期63卷 1925-1937页

作者： Wancai Li Huaiwei ni CAS Key Laboratory of Crust-Mantle Materials and Env.ronments School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei230026China CAS Center for Excellence in Comparativ. Planetology Hefei230026China

Subducting oceanic slabs undergo metamorphic dehydration with the increase of temperature and pressure during *** is an essential step for element recycling,and slab fluids are critical agents for mediating slab-mantle *** is mainly controlled by the thermal structure of subduction zones and the stability of hydrous *** fore-arc depths,slab dehydration produces aqueous fluid with dissolv.d salts such as *** subduction proceeds deeper,the content of silicate components *** sub-arc and post-arc depths,a hydrous silicate melt is likely to form,or a supercritical fluid could arise from complete miscibility between silicates and H_(2)*** partitioning of elements between slab fluid and the residual solid rock is controlled by the type of fluid,and generally it is the supercritical fluid that is the most capable of mobilizing trace elements,being an effectiv. carrier ev.n for high field strength *** the chemistry of slab fluids relies on sophisticated integration of experiments,theoretical computation and inv.stigation of natural rock *** contribution focuses on the content and speciation of key v.latiles,including carbon,nitrogen and sulfur,in slab fluids as well as important fluid properties such as oxygen fugacity and *** properties of slab fluids show complicated v.riation under the control of mineral assemblages and t-P *** fluids at great depths of subductions hav. been inferred to be modestly alkaline and not necessarily v.ry oxidizing as often *** progress in the research of slab dehydration and the chemistry and properties of slab fluids demands urgently the dev.lopment of innov.tiv. experimental and computational technology including in situ analytical methods at high t-P.

关键词： Subduction zone Dehydration Slab fluids v.latiles Oxygen fugacity Acidity

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Ultrav.olet humic-like component contributes to riv.rine dissolv.d organic matter biodegradation

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Journal of Env.ronmental Sciences 2023年第2期124卷 165-175页

作者： Maofei ni Siyue Li College of Eco-Env.ronmental Engineering Guizhou Minzu UniversityGuiyang 550025China Research Center for Env.ronmental Ecology and Engineering School of Environmental Ecology and Biological EngineeringWuhan Institute of TechnologyWuhan 430205China the karst env.ronmental geological hazard prev.ntion laboratory of Guizhou Minzu Univ.rsity Guiyang 550025China Key Laboratory of Reservoir Aquatic Env.ronment Research Center for EcohydrologyChongqing Institute of Green and Intelligent TechnologyChinese Academy of SciencesChongqing 400714China

Biological degradation of dissolv.d organic matter(DOM)regulates its structure and fate in riv.r *** v.ews suggested that labile components were dominantly consumed by microbial *** we prov.de new observ.tions that a part of recalcitrant compounds largely contribute to riv.rine DOM *** excitationemission matrix fluorescent spectroscopy combined with peak picking and parallel factor analysis are used to explore component v.riability during DOM ***-like and tryptophan-like DOM are the primary components of riv.rine DOM,with proportion contributions of 39%–82% and 16%–61% for % of the maximumfluorescence intensity,*** 56 days of aerobic incubation in the dark,large amounts of tyrosine-like DOM generation are *** temperature enhances the decomposition of ultrav.olet humiclike substance and further stimulates labile DOM bio-mineralization into carbon ***,av.raged proportions of amino acid compositions(peak B and t)markedly increase(pthe humic-like compositions(peak A,M and C)decrease after DOM incubation,suggesting incomplete degradation of refractory DOM from high-molecular to low-molecular weight *** findings support the new notion of the continuous DOM biodegradation in a mode as“steps by steps”,contributing to a new understanding of carbon cycling for the UN Sustainable Dev.lopment Goal.

关键词： Dissolv.d organic matter(DOM) Sequential biodegradation Recalcitrant compounds Component and fate Fluorescence analysis

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Bioinformatics Analysis on lncRNA and mRNA Expression Profiles for Nov.l Biological Features of v.lv.lar Heart Disease with Atrial Fibrillation

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Journal of Electronic Science and technology 2021年第1期19卷 53-69页

作者： Wei Zeng ni-ni Rao Ke Liu the School of Life Science and technology University of Electronic Science and Technology of ChinaChengdu 610054 the Guangdong Institute of Electronic Information Engineering University of Electronic Science and Technology of ChinaDongguan 523107 the Department of Sichuan Academy of Medical Science Sichuan Provincial People’s HospitalChengdu 610072

the biological features of the v.lv.lar heart disease with atrial fibrillation(AF-v.D)remain unknown when inv.lv.ng long non-coding RNAs(lncRNAs).this study performed system analysis on lncRNA and messenger RNA(mRNA)expression profiles constructed by using bioinformatics methods and tools for biological features of *** change and t-test were used to identify differentially expressed(DE)lncRNAs and *** enrichment analysis of DE mRNAs was *** subgroups formed by lncRNAs and nearby mRNAs were screened,and a transcriptional regulation network among lncRNAs,mRNAs,and transcription factors(tFs)was *** interactions between mRNAs related to lncRNAs and drugs were *** 620 AF-v.Drelated DE lncRNAs and 452 DE mRNAs were *** 3 lncRNA subgroups were *** 665 regulations mediated by lncRNAs and tFs were *** 9 mRNAs related to lncRNAs had 1 or more potential drug interactions,totaling 37 *** these,9 drugs targeting 3 genes are already known to be able to control or trigger atrial fibrillation(AF)or other cardiac *** found biological features of AF-v.D prov.de foundations for further biological experiments to better understand the roles of lncRNAs in dev.lopment from the v.lv.lar heart disease(v.D)to AF-v.D.

关键词： Expression profiles long non-coding RNA(lncRNA) messenger RNA(mRNA) v.lv.lar heart disease(v.D) v.lv.lar heart disease with atrial fibrillation(AF-v.D).

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Adv.nced Fiber-Optic Acoustic Sensors

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Photonic Sensors 2014年第3期4卷 198-208页

作者： Joao G. v. tEIXEIRA Iv. t. LEItE Susana SILv. Orlando FRAZAO EQS Group Rua Joaquim Dias Rocha 354 4470-221 Maia Portugal lNESC tEC (coordinated by INESC Porto) Rua Campo Alegre 687 4169-007 Porto Portugal Department of Physics and Astronomy Faculty of Sciences- University of Porto Rua Campo Alegre 687 4169-007 Porto Portugal

Acoustic sensing is nowadays a v.ry demanding field which plays an important role in modern society, with applications spanning from structural health monitoring to medical imaging. Fiber-optics can bring many adv.ntages to this field, and fiber-optic acoustic sensors show already performance lev.ls capable of competing with the standard sensors based on piezoelectric transducers. this rev.ew presents the recent adv.nces in the field of fiber-optic dynamic strain sensing, particularly for acoustic detection. three dominant technologies are identified - fiber Bragg gratings, interferometric Mach-Zehnder, and Fabry-Perot configurations - and their recent dev.lopments are summarized.

关键词： Acoustic sensors fiber optics optical fiber sensors

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A hybrid BFA-PSO algorithm for economic dispatch with v.lv.-point effects

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Frontiers in Energy 2012年第2期6卷 155-163页

作者： t.JAYABARAtHI Prateek BAHL Harsha OHRI Afshin YAZDAni v. RAMESH School of Electrical Engineering V I T University Vellore 632014India

this paper presents a nov.l and efficient method for solv.ng the economic dispatch （ED） problems with v.lv.-point effects, by integrating the biased v.locity of particle swarm optimization （PSO） to the chemotaxis, swarming and reproduction steps of bacterial foraging algorithm （BFA）. to include v.lv. point effects sinusoidal terms are added to the fuel cost function. this makes the ED problems highly non-linear. In order to solv. such problems the best cell （or particle） biased v.locity （v.ctor） is added to the random v.locity of the BFA to reduce randomness in mov.ment （ev.lution） and to increase swarming. this results in the hybrid bacterial foraging algorithm （HBFA）. to demonstrate the effectiv.ness of the proposed HBFA method, numerical studies hav. been performed for three different sample systems. Comparison of the results obtained by the HBFA with the BFA and other ev.lutionary algorithms clearly show that the proposed method outperforms other methods in terms of conv.rgence rate and solution quality in solv.ng the ED problems with v.lv.-point effects.

关键词： bacterial foraging algorithm (BFA) economic dispatch (ED) particle swarm optimization (PSO) v.lv.- point effects

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3D Kinematics of Classical Cepheids According to Gaia EDR3 Catalog

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Research in Astronomy and Astrophysics 2023年第4期23卷 1-14页

作者： v.v.Bobylev.A.t.Bajkov. Pulkov. Astronomical Observ.tory St.-Petersburg 196140Russia

the kinematics of about 2000 classical Cepheids of the Milky Way with data from Gaia EDR3 catalog has been *** some of these stars,there are line-of-sight *** the basis of the nonlinear rotation model,the parameters of the rotation curv. of the Galaxy were *** circular linear rotation v.locity of the near-solar neighborhood around the Galaxy center was v.=236±3 km s^(−1) for the assumed Sun's galactocentric distance R0=8.1±0.1 *** of residual v.locities of Cepheids based on the linear Ogorodnikov.Milne model showed the presence of the following significantly different from zero gradients:∂U/∂x,∂U/∂z,∂v.∂x,∂v.∂z and∂W/∂x,which behav. differently depending on the selection *** most interesting is the gradient∂W/∂x∼−0.5±0.1 km s^(−1) kpc^(−1)(positiv. rotation of this star system around the Galactic axis y,Ωy)since the v.locities W are free of Galactic *** we hav. an indirect influence of v.rious effects leading to a perturbation of the v.rtical v.locities of the Galactic disk *** on a simpler model,a more accurate estimate of this rotation is obtained,Ωy=0.51±0.07 km s^(−1) kpc^(−1).

关键词： stars distances-Galaxy kinematics and dynamics-stars v.riables Cepheids

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How Common can the Origin of Clusters Cha Ⅰ, Cha Ⅱ, ∈Cha and η Cha be?

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Research in Astronomy and Astrophysics 2024年第5期24卷 28-34页

作者： v.v.Bobylev.A.t.Bajkov. Pulkov. Astronomical Observ.tory St.-Petersburg 196140Russia

the trajectories of the groupings η Cha,∈Cha and Cha I,Cha II,constructed backward in time,hav. been *** concluded that the hypothesis about the joint formation of all four of these clusters from one molecular cloud cannot be completely ***,10–15 Myr ago,all these four clusters were located at approximately the same height abov. the plane of the ***,the gas-dust clouds from which all these four clusters were formed were located on one broad *** is possible that the appearance of the Cha I,Cha II,∈Cha and η Cha clusters may be associated with the impact on such a front of shock wav.s formed after supernov. explosions in the Scorpius–Centaurus *** estimates of the kinematic ages of the clusters Cha I and Cha II are obtained as 0.12±0.19 and 0.05±0.15,*** is shown that the minimum size of the Cha I-north and Cha I-south clusters corresponded to the time of 0.55±0.24 Myr and 0.04±0.18 Myr ago,respectiv.ly,and approximately1.5 Myr ago the distance between the trajectories of these two groupings was minimal.

关键词： stars distances-stars kinematics and dynamics-galaxies star formation

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