检索结果-南通市图书馆

In vivo and in vitro study of resorbable magnesium wires for medical implants:Mg purity,surface quality,Zn alloying and polymer coating

引用

Journal of Magnesium and Alloys 2024年第6期12卷 2472-2488页

作者： K.Tesar J.Luňácková M.Jex M.Žaloudková R.Vrbová M.Bartoš P.Klein L.Vištejnová J.Dušková E.Filová Z.Sucharda M.Steinerová S.Habr K.Balík A.Singh Department of Materials Faculty of Nuclear Sciences and Physical EngineeringCzech Technical University in PragueTrojanova 13Prague 12000Czech Republic Institute of Physics Czech Academy of SciencesNa Slovance 2Prague 18221Czech Republic Institute of Dental Medicine First Faculty of MedicineCharles University and General University Hospital in PragueKaterinská32Prague 12801Czech Republic Department of Physics Faculty of Nuclear Sciences and Physical EngineeringCzech Technical University in PragueBrehová7Prague 11519Czech Republic Department of Composites and Carbon Materials Institute of Rock Structure and MechanicsCzech Academy of SciencesV Holešovickách 41Prague 18209Czech Republic Institute of Anatomy First Faculty of MedicineCharles UniversityU Nemocnice 3Prague 12800Czech Republic Biomedical Center Faculty of Medicine in PilsenCharles UniversityAlej Svobody 76Pilsen 32300Czech Republic Department of Pathological Physiology Faculty of Medicine in PilsenCharles UniversityAlej Svobody 7632300 PilsenCzech Republic Department of Histology and Embryology Faculty of Medicine in PilsenCharles UniversityAlej Svobody 7632300 PilsenCzech Republic Institute of Pathology First Faculty of MedicineCharles University and General University Hospital in PragueStudnickova 2Prague 12800Czech Republic Department of Biomaterials and Tissue Engineering Institute of PhysiologyCzech Academy of SciencesVidenska 1083Prague 14200Czech Republic Research Center for Structural Materials National Institute for Materials Science1-2-1 SengenTsukuba 305-0047Japan

Magnesium is an excellent material in terms of biocompatibility and its corrosion products can serve as an active source for new bone ***,localized corrosion and H_(2)generation limit the potential of Mg-based *** low-alloyed Mg-Zn wires can strongly reduce problems with large H_(2)bubbles and improve the mechanical properties considerably while maintaining excellent long-term *** pickling and a polymer coating can be effectively used to lower the rate of in vivo *** this work,microstructural,mechanical,and in vitro characterization of 250μm and 300μm extruded wires made from ultra-pure Mg,commercially pure Mg,Mg-0.15Zn,Mg-0.4Zn and Mg-1Zn was ***,Mg-0.4Zn wires together with a variant coated with a copolymer of L-lactide andε-caprolactone were tested in vivo on artificially damaged Wistar rat *** on the observed Mg-induced osteogenesis,polymer-coated Mg wires with a small addition of Zn are a perspective material for bone-support applications,such as cerclage and fixation wires.

关键词： Magnesium Resorbable Mg wire Mg-Zn implant degradation Biocompatibility study Zn grain boundary segregation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Investigation of the tribological performance of ionic liquids in non-conformal EHL contacts under electric field activation

引用

Friction 2020年第5期8卷 982-994页

作者： Michal MICHALEC Petr SVOBODA Ivan KRUPKA Martin HARTL Aleksandar VENCL Faculty of Mechanical Engineering Brno University of TechnologyBrno 61669Czech Republic Central European Institute of Technology Brno University of TechnologyBrno 61200Czech Republic Faculty of Mechanical Engineering University of BelgradeBelgrade 11120Serbia South Ural State University Chelyabinsk 454080Russia

Real-time external alteration of the internal properties of lubricants is highly desirable in all mechanical systems. However, fabricating a suitable and effective smart lubricant is a long-lasting experimental process. In this study, the film thickness and frictional response of ionic liquid-lubricated non-conformal contacts to an electric field excitation under elastohydrodynamic conditions were examined. Film thickness was evaluated using a "ball-on-disc" optical tribometer with an electric circuit. Friction tests were carried on a mini traction machine (MTM) tribometer with a "ball-on-disc" rotation module and an electric circuit for contact area excitation. The results demonstrate that there is a difference in the behaviour of the ionic liquid during electric field excitation at the evaluated film thicknesses. The results of evaluated film thicknesses demonstrate that there is a difference in the behaviour of the ionic liquid during electric field excitation. Therefore, the ionic liquids could be a new basis for the smart lubrication of mechanical components. Moreover, the proposed experimental approach can be used to identify electrosensitive fluids.

关键词： friction thin film lubrication electro-rheological fluid smart fluid lubrication

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Rheology of Poly(vinyl butyral)Solution Containing Fumed Silica in Correlation with Electrospinning

引用

Chinese Journal of Polymer Science 2018年第6期36卷 742-748页

作者： Petra Peer Martina Polaskova Pavol Suly Institute of Hydrodynamics of the czech Academy of Sciences Pod Patankou 5166 12 Prague 6Czech Republic Centre of Polymer Systems Tomas Bata University in Zlintrida Tomase Bati 5678760 O1 ZlinCzech Republic Department of Polymer Engineering Faculty of TechnologyTomas Bata University in ZlinVavreckova 27576001 ZlinCzech Republic

The rheological properties in question are influenced by many factors, ranging from the characteristics of the given polymer or solvent to the flowing conditions. The primary focus of this study is to analyse the rheological behaviour of poly（vinyl butyral）—Mowital B 60 H—（PVB） solutions dissolved in methanol and a blend of these with fumed silica nanoparticles. The preparation of the nanofibrous web and the quality of nanofibres were correlated with the rheology of the polymer solution. It was discerned that drastically intensifying shear viscosity and the elasticity of the solution exerted a negligible effect on the formation of fibres, a finding which has rarely been discussed in the literature. The morphologies and structures of the PVB/silica nanofibrous membranes were investigated by scanning electron microscopy, thermogravimetric analysis and Fourier transform infrared spectroscopy.

关键词： Electrospinning Nanofibres Poly(vinyl butyral) Fumed silica Rheology

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Raman analysis of chemisorbed tribofilm for metal-on-polyethylene hip joint prostheses

引用

Biosurface and Biotribology 2021年第1期7卷 1-11页

作者： Risha Rufaqua Martin Vrbka Dušan Hemzal Dipankar Choudhury David Rebenda Ivan Křupka Martin Hartl Faculty of Mechanical Engineering Brno University of TechnologyBrnoCzech Republic Department of Condensed Matter Physics Faculty of ScienceMasaryk UniversityBrnoCzech Republic Nano Mechanics and Tribology Laboratory Department of Mechanical EngineeringUniversity of ArkansasFayettevilleArkansasUSA

The biochemical reaction during the formation of lubricant film the in case of a cobalt-chromium ball on an ultrahigh-molecular weight polyethylene cup was *** types of model synovial fluids and hyaluronic acid(HA)at physiologic concentrations were used in the *** coefficient of friction was measured using a pendulum hip simulator,and Raman spectroscopy was used to perceive chemical reactions between the synovial fluid and implant *** spectra evidenced that the three model fluids and HA chemisorbed onto the cobalt-chromium ***α-helix structure of the model fluid components was detected on the surface of the prosthesis.

关键词： material surface experiment

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Running-in friction of hip joint replacements can be significantly reduced:The effect of surface-textured acetabular cup

引用

Friction 2020年第6期8卷 1137-1152页

作者： David NECAS Hatsuhiko USAMI Tatsuya NIIMI Yoshinori SAWAE Ivan KRUPKA Martin HARTL Faculty of Mechanical Engineering Brno University of TechnologyBrno 61669Czech Republic Faculty of Science and Technology Meijo UniversityNagoya 468-8502Japan Kanefusa Corporation Nagoya 480-0192Japan Faculty of Engineering Kyushu UniversityFukuoka 819-0395Japan

Hip joint replacements represent the most effective way of treatment for patients suffering from joint *** the rapid improvement of implant materials over the last few decades,limited longevity associated with wear-related complications persists as the main ***,improved tribological perfor-mance is required in order to extend the service life of *** effect of surface texturing of ultra-high molecular weight polyethylene(UHMWPE)acetabular cup was investigated in the present *** tilling method was utilized for manufacturing the dimples with controlled diameter and depths on the contact surface of the *** experiments with four commercial femoral components and two model lubricants were *** main attention was paid to a coefficient of friction considering the differences between the original and the dimpled *** showed remarkable lowering of friction,in *** on the simulated human synovial fluid,friction was reduced by 40%(alumina ceramic),38.8%(zirconia toughened ceramic),25.5%(metal),and 9.9%(oxinium).In addition,the dimples helped to keep the friction stable without *** conclude,the paper brings a new insight into frictional behaviour of the hip replacements during running-in phase which is essential for overall implant *** is believed that proper surface texturing may rapidly improve the life quality of millions of patients and may lead to considerable financial savings.

关键词： hip joint replacement friction texturing dimple longevity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Leaf chlorophyll and nitrogen dynamics and their relationship to lowland rice yield for site-specific paddy management

引用

Information Processing in Agriculture 2017年第4期4卷 259-268页

作者： Asa Gholizadeh Mohammadmehdi Saberioon Lubos Boruvka Aimrun Wayayok Mohd Amin Mohd Soom Department of Soil Science and Soil Protection Faculty of AgrobiologyFood and Natural ResourcesCzech University of Life Sciences PraguePragueCzech Republic Laboratory of Signal and Image Processing Institute of Complex SystemsSouth Bohemia Research Centre of Aquaculture and Biodiversity of HydrocenosesFaculty of Fisheries and Protection of WatersUniversity of South Bohemia in Ceske BudejoviceNove HradyCzech Republic Department of Biological and Agricultural Engineering Faculty of EngineeringUniversity Putra MalaysiaSelangorMalaysia Faculty of Sustainable Agriculture University Malaysia SabahSandakanMalaysia

The optimum rate and application timing of Nitrogen(N)fertilizer are crucial in achieving a high yield in rice cultivation;however,conventional laboratory testing of plant nutrients is time-consuming and *** develop a site-specific spatial variable rate application method to overcome the limitations of traditional techniques,especially in fields under a double-cropping system,this study focused on the relationship between Soil Plant Analysis Development(SPAD)chlorophyll meter readings and N content in leaves during different growth stages to introduce the most suitable stage for assessment of crop N and prediction of rice *** SPAD readings and leaf N content were measured on the uppermost fully expanded leaf at panicle formation and booting *** yield was also measured at the end of the *** analysis of variance,variogram,and kriging were calculated to determine the variability of attributes and their relationship,and finally,variability maps were *** linear relationships were observed between attributes,with the same trends in different sampling dates;however,accuracy of semivariance estimation reduces with the growth *** of the study also implied that there was a better relationship between rice leaf N content(R^2=0.93),as well as yield(R2=0.81),with SPAD readings at the panicle formation ***,the SPAD-based evaluation of N status and prediction of rice yield is more reliable on this stage rather than at the booting *** study proved that the application of SPAD chlorophyll meter paves the way for real-time paddy N management and grain yield *** can be reliably exploited in precision agriculture of paddy fields under double-cropping cultivation to understand and control spatial variations.

关键词： Spatial variability Non-invasive measurement Precision farming Decision support

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Multi-Physics Analyses of Selected Civil Engineering Concrete Structures

引用

Communications in Computational Physics 2012年第8期12卷 885-918页

作者： J.Kruis T.Koudelka T.Krejcí Department of Mechanics Faculty of Civil EngineeringCzech Technical UniversityThákurova 7Prague16629Czech Republic

This paper summarizes suitable material models for creep and damage of concrete which are coupled with heat and moisture *** fully coupled approach or the staggered coupling is *** equations are spatially discretized by the finite element method and the temporal discretization is done by the generalized trapezoidal *** of non-linear algebraic equations are solved by the Newton *** of an efficient and extensible computer code based on the C++programming language is ***,successful analyses of two real engineering problems are described.

关键词： Coupled problems heat and moisture transfer creep damage mechanics hydrothermo-mechanical analysis efficient solvers analysis of containment watertightness of foundation slabs

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Can a dam type of an alpine lake be derived from lake geometry?A negative result

引用

Journal of Mountain Science 2021年第3期18卷 614-621页

作者： Adam EMMER Vojtěch CURIN University of Graz Institute of Geography and Regional ScienceCascade|The Mountain Processes and Mountain Hazards GroupGraz 8010Austria czech Academy of Sciences Prague 16500Czechia Global Change Research Institute Czech University of Life Sciences PragueFaculty of Environmental SciencesBrno 60300Czechia

Glacial lake outburst floods(GLOFs)represent one of the most serious hazard and risk in deglaciating high mountain regions worldwide and the need for GLOF hazard and risk assessment is *** a consequence,numerous region-and nation-wide GLOF assessment studies have been published *** studies cover large areas and consider hundreds to thousands of lakes,prioritizing the hazard posed by ***,certain simplification is required for executing such studies,often resulting in neglecting qualitative characteristics which would need manual *** lake dam types(e.g.,bedrock-dammed,moraine-dammed)are often not distinguished,despite they control GLOF mechanism(dam overtopping/dam breach)and thus GLOF *** this study,we explore the potential of easily measurable quantitative characteristics and four ratios to approximate the lake dam *** dataset of 851 lakes of the Cordillera Blanca suggests that while variances and means of these characteristics of individual lake types differ significantly(F-test,t-test),value distribution of different geometrical properties can’t be used for the originally proposed purpose along the *** only promising results are obtained for extreme values(selected bins)of the *** instance,the low width to length ratio indicates likely morainedammed lake while the high value of ratio indicating round-shape of the lake indicates increased likelihood of bedrock-dammed ***,we report a negative result of our experiment since there are negligible differences of relative frequencies in most of the bins along the spectra.

关键词： Alpine lake High mountain lake GLOFs Glacial lake Moraine-dammed Bedrock-dammed Negative result Cordillera Blanca

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Enhanced macrophage polarization induced by COX-2 inhibitor-loaded Pd octahedral nanozymes for treatment of atherosclerosis

引用

Chinese Chemical Letters 2023年第1期34卷 262-269页

作者： Min Xu Chuchu Ren Yue Zhou Zbynek Heger Xiaoyang Liang Vojtech Adam Nan Li School of Pharmaceutical Science and Technology Tianjin UniversityTainjin 300072China Department of Chemistry and Biochemistry Mendel University in BrnoBrno CZ-61300Czech Republic

Inhibition of foam cell formation is considered a promising treatment method for atherosclerosis,the leading cause of cardiovascular diseases ***,currently available therapeutic strategies have shown unsatisfactory clinical ***,herein,we design aloperine(ALO)-loaded and hyaluronic acid(HA)-modified palladium(Pd)octahedral nanozymes(Pd@HA/ALO)that can synergistically scavenge reactive oxygen species(ROS)and downregulate cyclooxygenase-2(COX-2)expression to induce macrophage polarization,thus inhibiting foam cell formation to attenuate *** to the targeted effect of HA on stabilin-2 and CD44,which are overexpressed in atherosclerotic plaques,Pd@HA/ALO can actively accumulate in atherosclerotic ***,the antioxidative effects of Pd octahedral nanozymes are mediated by their intrinsic superoxide dismutase-and catalase-like activities capable of effective scavenging of *** addition,anti-inflammatory effects are mediated by controlled,on-demand near-infrared-triggered ALO release leading to inhibition of COX-2 ***,the combined therapy can promote the polarization of macrophages to the M2 subtype by upregulating Arg-1 and CD206 expression and downregulating expression of TNF-α,IL-1βand IL-6,thereby inhibiting atherosclerosis-related foam cell *** conclusion,the presented in vitro and in vivo data demonstrate that Pd@HA/ALO enhanced macrophage polarization to reduce plaque formation,identifying an attractive treatment strategy for cardiovascular disease.

关键词： Atherosclerosis COX-2 inhibitor Pd octahedral nanozyme Macrophage polarization Anti-inflammation Antioxidation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Dynamics of lattice disorder in perovskite materials, polarization nanoclusters and ferroelectric domain wall structures

引用

npj Computational Materials 2023年第1期9卷 1137-1149页

作者： Jan Očenášek Ján Minár Jorge Alcalá New Technologies Research Centre University of West Bohemia in Pilsen30614 PlzeňCzech Republic Department of Materials Science and Metallurgical Engineering InSupETSEIBUniversitat Politècnica de Catalunya08028 BarcelonaSpain

The nexus between classic ferroelectricity and the structure of perovskite materials hinges on the concept of lattice *** the ordered perovskites display short-range displacements of the central cations around their equilibrium points,the lattice disorder dynamically unfolds to generate a myriad of distorted rhombohedral lattices characterized by the hopping of the central cations across*** is discovered that the lattice disorder correlates with the emergence of minimum configuration energypathways for the central cations,resulting in spatially modulated ultrafast polarization nanocluster arrangements that are stabilized by the electric charge defects in the *** high-resolution phonon dispersion analyses encompassing molecular dynamics(MD)and density functional theory(DFT)simulations,we provide unequivocal evidence linking the hopping of central cations to the development of diffuse soft phonon modes observed throughout the phase transitions of the *** massive MD simulations,we unveil the impact of lattice disorder on the structures of domain walls at finite-temperature vis-à-vis collective activation and deactivation of***,our simulations demonstrate the development of hierarchical morphotropic phase boundary(MPB)nanostructures under the combined influence of externally applied pressure and stress relaxation,characterized by sudden emergence of zig-zagged monoclinic arrangements that involve dualshifts of the central *** findings have implications for tailoring MPBs in thin-film structures and for the light-induced mobilization of *** are finally uncovered to the exploration of lattice disorder through gradual shear strain application.

关键词： perovskite lattice ferroelectric

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：