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Weak influence of natural vegetation in urban green spaces compared to agricultural ecosystems on House Martin populations:Insights from nationwide citizen science data in the Czech Republic

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Avian Research 2024年第2期15卷 139-146页

作者： Denisa Dvorakova jan Sipos Josef Suchomel Department of Zoology FisheriesHydrobiology and ApicultureMendel University in BrnoZemedelska 161300BrnoCzech Republic

The House Martin(Delichon urbicum)is a common farmland bird species in the European landscape,yet its population numbers are currently in ***,it is not yet sufficiently explained why this long-term decline *** fill this gap in our knowledge,we investigated how land cover composition affects the abundance of House Martins on the landscape scale by using nationwide citizen science *** a generalised linear mixed-effect model(GLMM),we evaluated 12,094 records from the Czech Republic spanning *** analysis underscores the significance of land cover type in shaping House Martin *** specifically,our results indicate that within agricultural land covers“naturally managed arable lands”exhibited significant positive effect,while forests,orchards,and vineyards were deemed less favourable for House Martin *** urban land covers,we found a clear distinction in the impact on House Martin populations,with a positive effect observed in urban infrastructure,development areas,and post-industrial sites(i.e.,UrbanAreas),while an indifferent impact was noted within urban green spaces and landscaped areas(i.e.,GreenUrban).Notably,our findings suggest that the simple spatial,age,and species structure typical of forests in Europe,and similarly,the uniform structure of parks and gardens,may be responsible for the decline in the abundance of the House *** advocate for the preservation or enhancement of urban greenery,expansion of natural vegetation in rural areas and adoption of ecological management practices in orchards and vineyards to mitigate further declines in House Martin populations.

关键词： Citizen science Habitat preferences House Martin Species distribution Urban and suburban landscape

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Establishing simulation model for optimizing efficiency of CNC machine using reliability-centered maintenance approach

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International Journal of Modeling, Simulation, and Scientific Computing 2019年第6期10卷 1-14页

作者： Zahid Hussain Hamid jan Sarhad University of Science and Information Technology Peshawar 25000Pakistan

The objective of this work was to enhance the product’s quality by concentrating on the machine’s optimized *** order to increase the machine’s reliability,the basis of reliability-centered maintenance approach was *** purpose was to establish a planned preventive maintenance strategy to identify the machine’s critical components having a noteworthy effect on the product’s *** critical components were prioritized using failure mode and effect analysis(FMEA).The goal of the study was to decrease the ppm time interval for a CNC machine by simulating the projected preventive maintenance time *** this purpose,the simulation software ProModel 7.5 was implemented for the current preventive maintenance procedure to choose the best ppm time interval which contributed better *** dissimilar optimization approaches were applied,however,the first approach yielded the prominent total system cost and the shorter ppm *** results of the study revealed that there was an increase of USD 1878 as a result of an increase in total system cost from USD 78,365 to USD 80,*** maintenance costs were reduced from USD 4196 to USD 2248(46%).The costs associated with good parts increased from USD 8259 to USD 8294(0.4%)and the costs associated with defective parts reduced from USD 171 to USD 3(98.25%),respectively.

关键词： Simulation model CNC machine reliability-centered maintenance(RCM) failure mode and effect analysis(FMEA) planned preventive maintenance

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Effects of acid deposition control in China:a review based on responses of subtropical forests

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Frontiers of Environmental Science & Engineering 2024年第6期18卷 115-126页

作者： Danni Xie Xiaodong Ge Lei Duan jan Mulder School of Land Engineering Chang’an UniversityXi’an 710064China State Key Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084China Faculty of Environmental Sciences and Natural Resource Management Norwegian University of Life SciencesBox 5003NO-1432ÅsNorway

For many decades,acid deposition used to pose a significant regional air pollution challenge in *** substantial emission control of anthropogenically derived sulfur and nitrogen containing gasses,both sulfur and nitrogen deposition,as well as the acid rain-affected area,have significantly decreased compared to their peak ***,particularly in the humid subtropics,are sensitive to acid deposition,as evidenced by soil acidification,sulfate and nitrate leaching in stream water,and elevated soil nitrous oxide *** in the total deposition of sulfur and nitrogen,caused a significant decline in sulfate and nitrate leaching from subtropical forest and subsequently in sulfate and nitrate concentrations in stream water,although there was about a 5-year *** delay may be attributed to the desorption of accumulated sulfate and continued elevated mineralization of accumulated nitrogen *** of nitrous oxide,a potent greenhouse gas,also declined in nitrogen-saturated subtropical forest soils,as soil water nitrate concentration ***,subtropical forests in China suffering from elevated acid deposition have begun to ***,the current levels of sulfur and nitrogen deposition continue to exceed the critical loads,i.e.,the assigned threshold levels in accordance with emission control policies,in more than 10%of the country’s land area,respectively,indicating remaining risks of acidification and ***,further emission reductions are urgently needed,also because they will help achieving goals related to air quality and nitrous oxide emissions.

关键词： Acidification Critical load Nitrous oxide Surface water chemistry Recovery

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Ballistic Testing and Thermal Behavior of Cast Double-base Propellant Containing BuNENA

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火炸药学报 2017年第6期40卷 23-28页

作者： Ahmed Maraden Petr Stojan Robert Matyas jan Zigmund Institute of Energetic Materials Faculty of Chemical TechnologyUniversity of PardubiceC Z OZM Research s.r.o.Bliznovice 32538 62 HrochUvT&necCZ Explosia a.s. Semtin 107530 02 PardubiceCzech Republic

Preparation of cast double-propellant grains depends on the ability of nitrocellulose powder to swell and coalesce into a coherent mass when treated with a suitable *** cast double-base process has been developed into a highly versatile technique for manufacturing solid rocket *** manufactured by this process provide a wide range of energies and burning *** preparation of cast double-base propellant grains has been performed using compatible casting liquid with the casting *** was used as an energetic plasticizer for manufacturing of casting *** rate measurements have been performed using closed bomb SV-2to investigate the burning behavior along a wide range of operating *** burning had been detected in pressure range(50-70)×105 Pa for the composition included *** and TGA thermal analysis were conducted to evaluate the thermal behavior of the prepared cast double-base *** from DTA were used to calculate the apparent activation energy.

关键词： cast double base propellant burning rate thermal analysis BuNENA plasticizer

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Solid Bi_(2)O_(3)-derived nanostructured metallic bismuth with high formate selectivity for the electrocatalytic reduction of CO_(2)

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 803-811页

作者： Xiaoyan Wang Safeer jan Zhiyong Wang Xianbo Jin College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power SourcesWuhan UniversityWuhan 430072China Engineering Research Center of Organosilicon Compounds&Materials Ministry of EducationWuhan 430072China

CO_(2) electrochemical reduction(CO_(2)ER)is an important research area for carbon ***,available catalysts for CO_(2) reduction are still characterized by limited stability and ***,metallic bismuth(Bi)has emerged as a promising catalyst for CO_(2) ***,we report the solid cathode electroreduction of commercial micronized Bi2O3as a straightforward approach for the preparation of nanostructured ***-1.1 V versus reversible hydrogen electrode in a KHCO3aqueous electrolyte,the resulting nanostructure Bi delivers a formate current density of~40 mA·cm^(-2) with a current efficiency of~86%,and the formate selectivity reaches97.6% at-0.78 *** nanosized Bi2O3as the precursor can further reduce the primary particle sizes of the resulting Bi,leading to a significantly increased formate selectivity at relatively low *** high catalytic activity of nanostructured Bi is attributable to the ultrafine and interconnected Bi nanoparticles in the nanoporous structure,which exposes abundant active sites for CO_(2) electrocatalytic reduction.

关键词： bismuth carbon dioxide electrocatalysis formate solid electroreduction

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Impact of atmospheric turbulence on coherent beam combining for laser weapon systems

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Defence Technology（防务技术） 2021年第4期17卷 1160-1167页

作者： jan K.Jabczyński Przemysław Gontar Military University of Technology Gen.S.Kaliskiego 2Warsaw00-908Poland

The performance of a laser weapon system based on coherent beam combining(CBC)depends on its propagation properties in the *** this study,an analytical model based on partial coherent beam combining(PCBC)for assumed coherence coefficients between beams in a CBC lattice was *** Kolmogorov model of atmospheric turbulence and the Hufnagel-Valley model of C^(2)_(n) dependence on atmospheric parameters were *** simplified metrics were proposed to assess the CBC *** beam profiles(super-Gaussian,truncated Gaussian,etc.)and geometries were analyzed in terms of maximal intensity in the far *** approximate formula for PCBC efficiency dependent on the Fried radius was *** results of CBC modeling were compared to those of the Gaussian beam propagation model in a turbulent *** dependence of CBC performance on the C^(2)_(n) parameter,range,and elevation angle was *** could be concluded that the application of CBC for medium and long range propagation is impractical without an effective adaptive optics system.

关键词： Laser beams Beam combining Coherence Atmosphere turbulences

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Fluid Structure Interaction Problems:the Necessity of a Well Posed,Stable and Accurate Formulation

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Communications in Computational Physics 2010年第10期8卷 1111-1138页

作者： jan Nordstrom Sofia Eriksson School of Mechanical Industrial and Aeronautical EngineeringUniversity of the WitwatersrandJohannesburgWITS 2050South Africa Department of Aeronautics and Systems Integration FOIThe Swedish Defense Research AgencySE-16490 StockholmSweden Department of Information Technology Division of Scientific ComputingUppsala UniversitySE-75105 UppsalaSweden

We investigate problems of fluid structure interaction type and aim for a formulation that leads to a well posed problem and a stable numerical *** first objective is to investigate if the generally accepted formulations of the fluid structure interaction problem are the only possible *** second objective is to derive a stable numerical *** accomplish that we will use a weak coupling procedure and employ summation-by-parts operators and penalty *** compare the weak coupling with other common *** also study the effect of high order accurate *** multiple dimensions this is a formidable task and we start by investigating the simplest possible model problem *** a flow model we use the linearized Euler equations in one dimension and as the structure model we consider a spring.

关键词： Fluid structure interaction well posed finite difference high accuracy stability

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Controlling Membrane Phase Separation of Polymersomes for Programmed Drug Release

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Chinese Journal of Polymer Science 2022年第9期40卷 1006-1015页

作者： Shuai Chen Erik jan Cornel Jian-Zhong Du Department of Orthopedics Shanghai Tenth People’s HospitalSchool of MedicineTongji UniversityShanghai 200072China Department of Polymeric Materials School of Materials Science and EngineeringTongji UniversityShanghai 201804China

Programmed release of small molecular drugs from polymersomes is of great importance in drug delivery.A significant challenge is to adjust the membrane permeability in a well-controlled ***,we propose a strategy for controlling membrane phase separation by photo-cross-linking of the membrane-forming blocks with different molecular *** synthesized three amphiphilic block copolymers with different membrane-forming blocks,which are poly(ethylene oxide)_(43)-b-poly((ε-caprolactone)_(45)-stat-((α-(cinnamoyloxymethyl)-1,2,3-triazol)caprolactone)_(25))(PEO_(43)-b-P(CL_(45)-stat-CTCL_(25))),PEO_(43)-b-P(CL_(108)-stat-CTCL_(16)),and PEO_(43)-b-PCTCL_(4)-b-PCL_(79).These polymers were self-assembled into polymersomes using either a solvent-switch or powder rehydration method,and the obtained polymersomes were characterized by dynamic light scattering and transmission electron *** the phase separation patterns within the polymersome membranes were investigated by mesoscopic dynamics(MesoDyn)*** further confirm the change of the membrane permeability that resulted from the phase separation within the membrane,doxorubicin,as a small molecular drug,was loaded and released from the *** to the incompatibility between membrane-forming moieties(PCTCL and PCL),phase separation occurs and the release rate can be tuned by controlling the membrane phase pattern or by ***,besides the compacting effect by formation of chemical bonds in the membrane,the cross-linking process can act as a driving force to facilitate the rearrangement and re-orientation of the phase pattern,which also influences the drug release behavior by modulating the cross-membrane distribution of the amorphous PCTCL *** this way,the strategy of focusing on the membrane phase separation for the preparation of the polymersomes with finely tunable drug release rate can be envisioned and designed accordingly,which is of great signifi

关键词： Polymersome Drug delivery Phase separation Programmed drug release

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Language, Conceptualization and TAM Marking： A Cognitive-functional Perspective

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外国语 2009年第1期32卷 2-43页

作者： jan Nuyts University of Antwerp Belgium

At the level of empirical phenomena,this paper deals with the system of 'Tense Aspect Modality' marking or of 'qualificational categories' in *** is this system organized? What are the principles behind it? The major focus is on the modal *** the theoretical level,this paper addresses issues pertaining to the organization and functioning of the cognitive systems involved in language use,with special focus on the differences and correspondences between two major theoretical strands in present day linguistics,viz.'functional linguistics' and 'cognitive linguistics'.

关键词：语言概念化认知功能英语语法

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Mechanical circulatory support in cardiogenic shock and post-myocardial infarction mechanical complications

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Journal of Geriatric Cardiology 2022年第2期19卷 130-136页

作者： Daniel Rob jan Bělohlávek nd Department of Medicine-Department of Cardiovascular Medicine First Faculty of MedicineCharles University and General University HospitalPragueCzech Republic

Despite advanced therapies,the mortality of patients with myocardial infarction(MI)complicated by cardiogenic shock(CS)remains around 50%.Mechanical complications of MI are rare nowadays but associated with high mortality in patients who present with *** treatment strategies and mechanical circulatory support(MCS)devices have been increasingly used to improve the grim prognosis of refractory *** article discusses current evidence regarding the use of MCS in MI complicated by CS,ventricular septal rupture,free wall rupture and acute mitral *** selection should be tailored according to the cause and severity of *** MCS initiation and multidisciplinary team cooperation is mandatory for good *** associated bleeding remains a major complication and an obstacle to better *** prospective randomized trials will improve current knowledge regarding MCS indications,timing,and patient selection in the coming years.

关键词： mortality infarction rupture

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