25 research outputs found
The Effect of SEBS/Halloysite Masterbatch Obtained in Different Extrusion Conditions on the Properties of Hybrid Polypropylene/Glass Fiber Composites for Auto Parts
Masterbatches from a linear poly[styrene-b-(ethylene-co-butylene)-b-styrene] (SEBS) and halloysite nanotubes (HNT-QM) were obtained in different conditions of temperature and shear using two co-rotating twin-screw extruders. The influence of screw configuration and melt processing conditions on the morpho-structural, thermal and mechanical properties of masterbatches at macro and nanoscale was studied. A good dispersion of halloysite nanotubes and better thermal stability and tensile and nanomechanical properties were obtained at a lower temperature profile and higher screw speed. The effect of masterbatches, the best and worst alternatives, on the properties of a polypropylene (PP)–glass fiber (GF) composite was also evaluated. Double hardness, tensile strength and modulus and four times higher impact strength were obtained for PP/GF composites containing masterbatches compared to pristine PP. However, the masterbatch with the best properties led further to enhanced mechanical properties of the PP/GF composite. A clear difference between the effects of the two masterbatches was obtained by nanoindentation and nanoscratch tests. These analyses proved to be useful for the design of polymer composites for automotive parts, such as bumpers or door panels. This study demonstrated that setting-up the correct processing conditions is very important to obtain the desired properties for automotive applications
Principles and technologies of historical structures consolidation, case study of Banloc castle complex
Historical monuments (palaces, churches, protected urban areas, so on) are integral part of the national cultural heritage which need activities and measures to protect them. The Banloc complex, located in the west of Romania, encompasses five buildings: the castle, the hunting pavilion, the kitchen, housekeeper house, and the stall. This study involves historical, architectural, structural and physical-chemical investigations with the aim of finding the correct restoration solutions, in good agreement with the Venice Charter, respectively the Nara Charter. Being affected by time and by the seismic sequence (Mw 5.6), the restoration of the building is absolutely necessary for recovering the functionality, structural solution and highlighting the artistic elements. Some analytical techniques, as: X-ray diffraction (XRD), Wavelength Dispersive X-ray fluorescence (WDXRF), optical microscopy (OM), and zoom microscopy, Infrared spectroscopy Fourier Transformed (FTIR), and Raman spectroscopy, have been used in this paper in order to clarify the main aspects about the structure, composition and morphological of the samples collected from Pavilion building. The oxides composition, and the possible organic impurities has been identified by WDXRF amd FTIR/Raman spectra, respectively. The microscopy images revealed the colours, fissures, cracks and even holes due to the time weathering processes, and damages they suffered in time
A multi-photon Stokes-parameter invariant for entangled states
We consider the Minkowskian norm of the n-photon Stokes tensor, a scalar
invariant under the group realized by the transformations of stochastic local
quantum operations and classical communications (SLOCC). This invariant is
offered as a candidate entanglement measure for n-qubit states and discussed in
relation to measures of quantum state entanglement for certain important
classes of two-qubit and three-qubit systems. This invariant can be directly
estimated via a quantum network, obviating the need to perform laborious
quantum state tomography. We also show that this invariant directly captures
the extent of entanglement purification due to SLOCC filters.Comment: 9 pages, 0 figures, Accepted for publication in Physical Review
Transforming growth factor β-mediated micromechanics modulates disease progression in primary myelofibrosis.
To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked DownloadPrimary myelofibrosis (PMF) is a Ph-negative myeloproliferative neoplasm (MPN), characterized by advanced bone marrow fibrosis and extramedullary haematopoiesis. The bone marrow fibrosis results from excessive proliferation of fibroblasts that are influenced by several cytokines in the microenvironment, of which transforming growth factor-β (TGF-β) is the most important. Micromechanics related to the niche has not yet been elucidated. In this study, we hypothesized that mechanical stress modulates TGF-β signalling leading to further activation and subsequent proliferation and invasion of bone marrow fibroblasts, thus showing the important role of micromechanics in the development and progression of PMF, both in the bone marrow and in extramedullary sites. Using three PMF-derived fibroblast cell lines and transforming growth factor-β receptor (TGFBR) 1 and 2 knock-down PMF-derived fibroblasts, we showed that mechanical stress does stimulate the collagen synthesis by the fibroblasts in patients with myelofibrosis, through the TGFBR1, which however seems to be activated through alternative pathways, other than TGFBR2.
Keywords: TGF-β; fibroblast activation; invasion; micromechanics; myelofibrosis; proliferation.School of Doctoral Studies-Iuliu Hatieganu University
Romanian Government
Ion Chiricuta Oncology Institute Cluj Napoca
international collaborative grant of the European Economic Space between Romania and Iceland 2020-2022
1
A Review of Swarm-Based 1D/2D Signal Processing
While swarming behavior, widely encountered in nature, has recently sparked numerous models and interest in domains as optimization, data clustering, and control, their application to signal processing remains sporadic. In this paper I provide a unitary treatment and a review of former results obtained in signal filtering and enhancement using swarms. General equations are presented for these procedures and stability issues are considered, with examples. The paper overviews several swarming model I introduced in previous papers and provides new evidence of the applicability of these models in signal processing. In all the models for 1D signal processing, the key idea is that the swarm hunts a prey that impersonates the filtered signal. In the 2D models, the signal (image) represents the “landscape” over which the swarm moves at a distance, while the swarm interacts with the signal (landscape). I provide and discuss details of the underlying theory of the models for processing time-domain signals and images. While this paper partly follows and summarizes previous papers, it nevertheless includes supplementary theoretical and algorithmic considerations and new results for both 1D and 2D signal processing. Although following either biological models or physical models in swarm algorithms is not generally accepted for technical applications, we prefer to emphasize the analogies established by our biomimetic approach with these two groups of models
Dimensions of the destination’s sensory profile. Case study: Muntenia
The development of a destination sensory brand represents a complex
process, given the multitude of product components, and, by integrating their
specific sensory dimensions in their brand platform, can transform the interaction
tourist – destination into a memorable experience. In this sense, the achievement of
the destination’s sensory profile constitutes the first step, in which its perceived
sensory dimensions for the elements of attraction and for the representative types
of tourism are analyzed. In this paper, it is attempted, based on some research, to
outline the sensory profile for the destination Muntenia, starting from the sensory
dimensions perceived by tourists
Sensory marketing strategies. Case study: Oltenia
From the perspective of the tourist, sensory marketing strategies may
result in an experience improvement which leads, in time, to acquiring a positive
destination image, and, from the perspective of the destination, to furthering its
harmonious development. Even though it appears that sensory marketing strategies
can be considered as alternatives for marketing strategies, they actually are
complementary, and their objective (increasing product quality by “turning to the
beginning”, where perception and consumer knowledge start), aims to handle the
senses of the consumer by starting from the identification of his/her needs