The aims of this study were to determine vertebral heart size (VHS) in stray cats and to compare different radiographic views. This study was performed on 50 adult stray cats. All cats were short-haired and non-obese and were considered to be healthy based on physical examination and electrocardiography. Left and right lateral, dorsoventral and ventrodorsal radiographs were taken. The long and short axes of the heart were measured in millimetres. The thoracic vertebral length spanned by each dimension was measured caudally from the fourth thoracic vertebra. Mean+/-SD and the correlation coefficient between the measurements were calculated with standard statistical software. The sum of the long and short axes of the heart expressed as VHS was 7.3+/-0.49 vertebrae in right lateral, 7.3+/-0.55 vertebrae in left lateral, 7.5+/-0.68 vertebrae in dorsoventral and 7.5+/-0.53 vertebrae in ventrodorsal. The differences between right and left lateral as well as dorsoventral and ventrodorsal views were not significant (P>0.05). Absolute measurements and vertebral heart scale values were slightly smaller than those reported in the literature for mixed population of cats. It is, therefore, important to take the breed in to account.
A trifunctional organo alkoxysilane (3-aminopropyl)triethoxysilane (c-APS) has been used as reagent for the chemical modification of montmorillonite clay. Silane grafting was taken place in dry and hydrolyzing conditions. Silane grafted and pristine clay took part in interfacial polycondensation process to deposit a layer of nylon-66 onto the clay lamellae and therefore, enhance their affinity with nylon-66 matrix. Evidence of presence of grafted silane molecules and deposition of nylon-66 on clay particles were provided by Fourier transform-infrared, thermogravimetric analysis (TGA), and X-ray diffraction (XRD). Such modified clays and pristine clays were melt compounded with nylon-66. The structures of the resulting nylon composites were characterized using XRD and transmission electron microscopy and the results showed presence of both intercalation and exfoliation. TGA thermograms of nanocomposites indicated improved thermal stability upon the incorporation of silane grafted montmorillonite. Furthermore, differential scanning calorimetry scans showed that silane modified clays promoted crystallization in nanocomposites. Increase of storage modulus and depression of tan d peak in nanocomposites in dynamical mechanical thermal analysis were observed. The rheological properties of nylon-66 and nanocomposites were also evaluated and differences in values of complex viscosity of samples were noticed.
Oriented HDPE films having a stacked lamellar morphology were prepared to develop microporous membranes through cast film extrusion followed by stretching. Applying higher draw ratios (DR) and annealing the cast films improved crystal alignments remarkably. It was shown the improvement in c-axis orientation upon annealing was more significant for the films prepared with lower DR. Furthermore, applying Raman spectroscopy, the amorphous mass fraction of the films was obtained. Subsequently, considering a three-phase structure (i.e., crystal, amorphous and interphase), the interphase content of the films was also determined. A distinct DR dependence of the interphase content was noticed. It was observed that in addition to crystal perfection upon annealing, the amorphous phase fraction was also decreased due to possibly increase in free volume, promoting lamellar separation and cavitation during the subsequent stretching step. SEM images of the membranes surfaces as well as their normalized water vapor transmission rate (WVTR) values indicated a more uniform pore formation and increased permeability with DR. Furthermore, it was found that lower interphase content in the films with higher DR favors lamellar separation. However, permeability in the stretched precursor films with DR higher than a certain level (DR 5 93) was not improved significantly. Moreover, crystallinity and crystal orientation of produced membranes were investigated.
Ethylene-vinyl alcohol copolymers (EVOH), with appropriate barriers and processability, can be chemically modified through vinyl alcohol units. Amides and polyamides based on condensation reactions of adipoyl chloride and hexamethylenediamine were grafted onto EVOH. Grafting was characterized by contact angle measurement, attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), nuclear magnetic resonance spectroscopy (NMR) and scanning electron microscopy (SEM). Amide peaks at 3302 cm -1 corresponding to -NH bond stretching and the absorption of HN-CH 2 at 7.8 ppm, were observed from ATR-FTIR and NMR, respectively, as a result of grafting. SEM showed the formation of amide structures as bundles, agglomerates and needle-like particles. Differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA) showed considerable changes in onset of melt temperature, crystallinity and various transitions in grafted EVOH, showing an effective alteration in the physical properties compared with the virgin resin. Nylon grafted EVOH can be considered as a potential compatibilizer in polyethylene (PE)/polyamide blends via increasing interactions at the interface.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.