Search results for "Spinning"

Tailored electrospun nanofibrous polycaprolactone/gelatin scaffolds into an acid hydrolytic solvent system

2018

[EN] Blended nanofibrous scaffolds based on polycaprolactone (PCL) and gelatin (Ge) were successfully prepared. A formic/acetic acid (1:1) mixture was used to dissolve PCL/Ge blends from 100/0 to 20/80 %wt in steps of 10 %wt. The hydrolysis of the PCL diluted in the formic/acetic acid mixture was considered as a method for tailoring the surface morphology and physicochemical features of the nanofibrous PCL/Ge scaffolds as a function of the dissolution time. The fibre diameter remained in the nanoscale range for all the studied scaffolds, which is crucial to mimic the extra-cellular matrix size. The reduction of the intrinsic viscosity, molar mass and hydrodynamic radius found for the PCL mo…

Multinuclear and Solid State NMR of Gels

2020

Over the past six decades, nuclear magnetic resonance spectroscopy has been an integral part of synthetic organic and organometallic chemistry, as well as biochemistry. Beyond solution state experiments, increasing developments have opened new avenues to study materials in their solid state. Between two extremes (i.e., solution and solid), there exist several other forms of materials, especially soft materials such as gels and liquid crystals. Traditionally gels have been studied using solution state NMR spectroscopic methods. However, the viscosity of complex viscoelastic fluids such as gels affects the molecular tumbling, which in turn affects the chemical shift anisotropy and dipolar and…

Parasitoids (Hymenoptera) of leaf-spinning moths (Lepidoptera) feeding on Vaccinium uliginosum L. along an ecological gradient in central European pe…

2011

Parasitoids of leaf-spinning Lepidoptera associated with two isolated central European peat bogs were investigated. Five families of parasitoid Hymenoptera (Braconidae, lchneumonidae, Eulophidae, Pteromalidae and Encyrtidae) were recorded. Three categories were recognised: (1) primary parasitoids, (2) facultative hyperparasitoids and (3) obligatory hyperparasitoids. Ten species of Braconidae, five species and seven marked morphospecies among lchneumonidae, and three species of Chalcidoidea were identified. Despite of some niche-specific (but less host-specific) parasitoids, all these hymenopterans are likely to be generalists and none of them were confirmed to be habitat and/or host special…

Significant modifications in body composition and cardio-respiratory fitness induced by a specific indoor cycling protocol

2008

Fusingin vivoandex vivoNMR sources of information for brain tumor classification

2011

In this study we classify short echo-time brain magnetic resonance spectroscopic imaging (MRSI) data by applying a model-based canonical correlation analyses algorithm and by using, as prior knowledge, multimodal sources of information coming from high-resolution magic angle spinning (HR-MAS), MRSI and magnetic resonance imaging. The potential and limitations of fusing in vivo and ex vivo nuclear magnetic resonance sources to detect brain tumors is investigated. We present various modalities for multimodal data fusion, study the effect and the impact of using multimodal information for classifying MRSI brain glial tumors data and analyze which parameters influence the classification results…

Electrospun bioactive mats enriched with Ca-polyphosphate/retinol nanospheres as potential wound dressing

2015

Background While electrospun materials have been frequently used in tissue engineering no wound dressings exist that significantly improved wound healing effectively. Methods We succeeded to fabricate three-dimensional (3D) electrospun poly(D,l-lactide) (PLA) fiber mats into which nanospheres, formed from amorphous calcium polyphosphate (polyP) nanoparticles (NP) and encapsulated retinol (“retinol/aCa-polyP-NS” nanospheres [NS]), had been incorporated. Results Experiments with MC3T3-E1 cells revealed that co-incubation of the cells with Ca-polyP together with retinol (or incubation with retinol/aCa-polyP-NS) resulted in a significant synergistic effect on cell growth compared with particle-…

Melt-spun conductive fibers containing functionalized CNTs

2013

Multifunctional fibers based on polyamide 6 and plasma functionalized carbon nanotubes.

2013

Orientation and exfoliation of clay nanoparticles in the spinning of a nanobiocomposite sample

2016

Polymer nanobiocomposites represent a new group of materials filled with inert nanosized particles that show very interesting properties with respect to the matrix and the same biodegradability of the matrix. In this work we have studied the effect of the elongational flow on the morphology and dynamic-mechanical properties of a new nanobiocomposite made by a matrix of biodegradable PLA and a filler of organomodified montmorillonite.

PEDOT saturošu nanošķiedru iegūšana, izmantojot elektrovērpšanas metodi, un to elektrisko īpašību raksturošana

2020

Šajā darbā ir veikti pētījumi ar PEDOT:PSS polimēra nanodiegiem un plānajām kārtiņām. Nanodiegi tika iegūti izmantojot elektrovērpšanas metodi. Tika pētītas iegūto paraugu īpašības – elektriskā vadītspēja un Zēbeka koeficients, kā arī nanodiegu dimensionālie lielumi. Šī pētījuma mērķis ir iegūt nanodiegus ar pēc iespējas augstāku elektrisko vadītspēju. Tas tiek panākts palielinot PEDOT:PSS polimēra koncentrāciju šķīdumos, pārbaudot arī šķīdumu, kurā nav pievienots PEDOT:PSS polimērs. Ir izmērītas īpatnējās elektriskās vadītspējas un Zēbeka koeficienti nanodiegu un plāno kārtiņu paraugiem. Iegūtās vadītspējas un Zēbeka koeficienti ir salīdzināti savā starpā, lai saprastu elektrovērpšanas pro…