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New design paradigm for heterogeneous catalysts

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National Science Review 2015年第2期2卷 140-143页

作者： aleksandra Vojvodic Jens K.N?rskov SUNCAT Center for Interface Science and Catalysis SLAC National Accelerator Laboratory Department of Chemical Engineering Stanford University

Both scientiic discovery and technological development are at some point faced with the question of how to progress from a trial-and-error approach to a highly controlled design *** heterogeneous catalysis,the search for the optimal active site of a catalyst for a given chemical reaction has been the central objective of research for almost a ***

关键词： New design paradigm for heterogeneous catalysts

Development and actualization of brownfields database with the use of unmanned aerial vehicles-the case of Upper Silesia,Poland

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International Journal of Coal Science & Technology 2022年第6期9卷 168-177页

作者： aleksandra Zgórska Adam Hamerla Jan Bondaruk Pawel Zawartka Department of Water Protection Central Mining InstitutePlac Gwarków 144-166 KatowicePoland Deputy Director for Environmental Engineering Central Mining Institute Plac Gwarkow 144-166 KatowicePoland

This paper presents the assumptions and the preliminary results of the project entitled"Extension of the system for man-agement of post-mining areas in the Silesian province-OPI TPP 2.0".The overall objective of the project is to develop and implement a new e-service in the form of an open-access information system on post-mining areas in the Silesia *** range of information and tools planned to be made available is dedicated to assessing the possibilities and potential for economic and social reuse of these *** basic and extremely important stage of the project was to identify and collect data on post-industrial sites located in the Silesia *** information contained in this article illustrates the activities that were carried out in the initial phase of the project in which unmanned aerial vehicles(UAV)were used to identify and acquire information on brownfields(including post-mining sites)entered into the developed common *** article assesses the possibility of using drones in an enterprise of such a large scale and also points out the advantages of using this *** article describes the methodology and scope of work related to the acquisition of data that can be collected using unmanned aerial vehicle(UAV)covering surface infrastructure and land use of brownfields,allowing for the identification of negative phenomena on their site as well as monitoring of naturally occurring *** on fieldworks experience and the results of numerous analyses carried out for different types of brownfields(***-mining areas,former transport bases,settling ponds,etc.),paper presents the advantages and benefits of drones(UAN)over other data sources used to monitor changes in an *** article is based on the results of an inventory of over 600 brownfields located in Upper Silesia region(Silesia Voivodeship,Poland).

关键词： Unmanned aerial vehicle Brownfields Post-industrial sites Databases Drones

Impact of Natural Oil-Based Recycled Polyols on Properties of Cast Polyurethanes

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Journal of Renewable Materials 2018年第7期6卷 697-706页

作者： Hynek Beneš aleksandra Paruzel JiříHodan Olga Trhlíková Institute of Macromolecular Chemistry AS CR v.v.i.Heyrovsky Sq.216206 Prague 6Czech Republic

In this study, castor oil, rapeseed oil and medium chain triglycerides of coconut oil, were transesterified bymeans of 2-ethyl-2-hydroxymethyl-1,3-propanediol (trimethylolpropane) and consequently used to convertpolycarbonate waste from end-of-life vehicles into liquid polyols. The prepared recycled polyols, composeduniquely of renewable and recycled components, had a hydroxyl number of ca. 250 mg KOH·g−1. They weresuccessfully applied as 100% replacement of a virgin polyol for preparation of solid crosslinked polyurethanes(PU) by solvent-free casting. The produced rigid cast PU exhibited the main transition temperature rangingfrom 44°C to 53°C, the hardness value from 46 to 61 Shore D and the beneficial low water absorption (0.4-0.5wt.%). The PU network structure was highly influenced by the presence of aromatic structures ofpolycarbonate-units and fatty acid compositions. A suitable selection of natural oil thus enabled to adjustthermo-mechanical properties and promote excellent optical transparency of the produced PU.

关键词： Natural oil cast polyurethane bio-based polycarbonate waste recycling

Inflammatory priming of mesenchymal stem cells:Focus on growth factors enhancement

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BIOCELL 2022年第9期46卷 2049-2052页

作者： aleksandra GORNOSTAEVA ELENA ANDREEVA LUDMILA BURAVKOVA Cell Physiology Laboratory Institute of Biomedical Problems of Russian Academy of SciencesMoscow123007Russia

Multipotent mesenchymal stromal cells(MSCs)are actively involved in reparation and inflammation processes,providing damaged tissue reparation and suppressing immune cell responses in *** effects are mostly due to the production of a wide range of paracrine factors,including growth factors and immunomodulatory *** induce immunosuppressive activity,MSCs are primed by inflammatory cytokines,which results in an increased production of immunomodulatory ***,stimulation of reparative properties is also *** viewpoint manuscript highlights the possibilities of inflammatory priming to increase the production of growth factors by MSCs.

关键词： Multipotent mesenchymal stromal cells Priming Growth factors

Bracken-induced increase in soil P availability, along with its high P acquisition efficiency, enables it to invade P-deficient meadows

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Journal of Plant Ecology 2022年第4期15卷 783-794页

作者： Antun Jelinčić Nina Šajna Željka Zgorelec aleksandra Perčin Ćire Truhelke 1510000 ZagrebCroatia University of Maribor Faculty of Natural Sciences and MathematicsDepartment of BiologyMariborSlovenia University of Zagreb Faculty of AgricultureDepartment of General AgronomyZagrebCroatia

Changes in soil chemistry after invasion by bracken(Pteridium aquilinum)have been studied in heathlands,but comparable studies in meadows are *** investigated if bracken invasion into P-deficient meadows alters the soil nutrient-resource pool,as well as the mechanisms behind it linked to soil processes and bracken ***,we investigated how community composition responds to differences in soil chemistry before and after the *** and plant material sampling,along with vegetation survey,were performed during bracken peak *** analyses included analysis of variance and canonical correspondence analysis(CCA).Bracken invasion increased soil P availability,soil organic C concentration,as well as C:N,C:S and N:S ratios,while decreasing Fe and Co *** pinnae were rich in P,and its rhizomes were rich in K,whereas N:P of pinnae and rhizomes was *** showed contrasting abundance patterns of frequent meadow species related to P and K *** lanatus exhibited competitive advantage under extremely low P *** in P availability under bracken may have occurred through promoting the leaching of Fe and *** increasing P availability for its growth and increasing N limitation for other species,bracken can gain a competitive advantage from the soil resource-niche *** ability to increase soil P availability,along with the physiological mechanisms behind its high P acquisition efficiency,seem to differentiate bracken from other species of competitive ecological strategy,which are mainly confined to nutrient-rich *** enabled bracken to invade P-deficient meadows.

关键词： Pteridium aquilinum vegetation succession biogeochemical processes plant–soil feedbacks Holcus lanatus phosphorus limitation plant invasion

Stable optical vortices in nonlinear multicore fibers

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Light(Science & Applications) 2015年第1期4卷 245-250页

作者： Ljupco Hadzievski aleksandra Maluckov Alexander MRubenchik Sergei Turitsyn Vinca Institute of Nuclear Sciences University of BelgradeP.O.Box 52211001 BelgradeSerbia Lawrence Livermore National Laboratory LivermoreCalifornia 94550USA Aston Institute of Photonic Technologies Aston UniversityB47ET BirminghamUK Laboratory of Nonlinear Photonics Novosibirsk State UniversityNovosibirsk630090Russia

The multicore fiber(MCF)is a physical system of high practical *** addition to standard exploitation,MCFs may support discrete vortices that carry orbital angular momentum suitable for spatial-division multiplexing in high-capacity fiber-optic communication *** discrete vortices may also be attractive for high-power laser *** present the conditions of existence,stability,and coherent propagation of such optical vortices for two practical MCF *** optimization,we found stable discrete vortices that were capable of transferring high coherent power through the MCF.

关键词： coherent energy propagation multicore fibers nonlinear vortices

Taming desynchronized bursting with delays in the Macaque cortical network

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Chinese Physics B 2011年第4期20卷 117-122页

作者：王青云 Murks aleksandra Perc Matjaz 陆启韶 Department of Dynamics and Control Beihang University Department of Physics Faculty of Natural Sciences and MathematicsUniversity of Maribor

Inhibitory coupled bursting Hindmarsh-Rose neurons are considered as constitutive units of the Macaque corti- cal network. In the absence of information transmission delay the bursting activity is desynchronized, giving rise to spatiotemporally disordered dynamics. This paper shows that the introduction of finite delays can lead to the synchro- nization of bursting and thus to the emergence of coherent propagating fronts of excitation in the space-time domain. Moreover, it shows that the type of synchronous bursting is uniquely determined by the delay length, with the transi- tions from one type to the other occurring in a step-like manner depending on the delay. Interestingly, as the delay is tuned close to the transition points, the synchronization deteriorates, which implies the coexistence of different bursting attractors. These phenomena can be observed by different but fixed coupling strengths, thus indicating a new role for information transmission delays in realistic neuronal networks.

关键词： synchronization bursting information transmission delay Macaque cortical network inhibitory coupling

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Novel synthesis method combining a foaming agent with freeze-drying to obtain hybrid highly macroporous bone scaffolds

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Journal of Materials Science & Technology 2020年第8期36卷 52-63页

作者： Paulina Kazimierczak aleksandra Benko Krzysztof Palka Cristina Canal Dorota Kolodynska Agata Przekora Department of Biochemistry and Biotechnology Medical University of LublinChodzki 120-093LublinPoland AGH University of Science and Technology Faculty of Materials Science and CeramicsA.Mickiewicza 30 Ave.30-059KrakowPoland Department of Materials Engineering Lublin University of TechnologyNadbystrzycka 3620-618LublinPoland Biomaterials Biomechanics and Tissue Engineering GroupDepartment of Materials Science and MetallurgyUniversitat Politècnica de CatalunyaBarcelona08019Spain Research Centre in Multiscale Science and Engineering Universitat Politècnica de CatalunyaBarcelona08019Spain Department of Inorganic Chemistry Maria Curie-Sklodowska UniversityMaria Curie Sklodowska Sq.220-031LublinPoland

Three-dimensional macroporous scaffolds are commonly used in bone tissue engineering applications since they provide sufficient space for cell migration and proliferation, facilitating bone ingrowth and implant vascularisation. The aim of this work was to combine two simple methods, freeze-drying and gas-foaming, in order to fabricate highly macroporous bone scaffolds made of chitosan/agarose matrix reinforced with nanohydroxyapatite. The secondary goal of this research was to comprehensively assess biomedical potential of developed biomaterials. In this work, it was demonstrated that simultaneous application of freeze-drying and gas-foaming technique allows to obtain hybrid(as proven by ATR-FTIR)macroporous bone scaffolds(pore diameter > 50 um) characterized by high open(70%) and interconnected porosity. Novel scaffolds were non-toxic, favoured osteoblasts adhesion and growth and induced apatite formation on their surfaces, indicating their high bioactivity that is essential for good implant osseointegration. Biomaterials were also prone to enzymatic degradation, degradation in acidified microenvironment(e.g. osteoclast-mediated), and slow degradation under physiological p H of ***, the scaffolds revealed microstructure(70% open porosity, SSA approx. 30 m2/g, high share of macropores with diameter in the range 100-410 um) and compressive strength(1–1.4 MPa) comparable to cancellous bone, indicating that they are promising implants for cancellous bone regeneration.

关键词： Agarose Chitosan Nanohydroxyapatite Biomaterial porosity Biodegradation Cryogel

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Assessing suspended sediment fluxes with acoustic Doppler current profilers:case study from large rivers in Russia

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Big Earth Data 2022年第4期6卷 504-526页

作者： Sergey Chalov Vsevolod Moreido Victor Ivanov aleksandra Chalova Faculty of Geography Lomonosov Moscow State UniversityMoscowRussia Institute of Physics Kazan Federal UniversityKazanRussia Flood Hydrology Lab Water Problems Institute of Russian Academy of SciencesMoscowRussia

Surrogate measures are becoming increasingly used to measure suspended sediment flux,but only few particular computer techniques of data processing are recently *** study demonstrates capabilities of acoustic Doppler current profilers(ADCPs)to infer information regarding suspended-sand concentrations in river systems and calculate suspended sediment flux via big data analytics which includes process of analyzing and data mining of measurements based on ADCP signal backscatter intensity *** present here specific codes done by R language using RStudio software with open-source tidyverse and plotly packages aimed to generate tables containing data of suspended load for cells,verticals and whole cross-section based on backscattering values from 600 kH Teledyne RDInstruments RioGrande WorkHorse ADCP unit,as well perform estimates of morphometric,suspended sediment concentration(SSC)and velocity characteristics of the *** developed tools enabled to process large data array consisting of over 56,526,480 geo-referenced values of river depth,streamflow velocity,and backscatter intensity for each river cross-section measured at six case study sites in Russia.

关键词： Big data ADCP backscatter intensity sediment transport