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71.
A femoral artery pseudoaneurysm is one complication of vascular intervention, and the incidence is increasing. Early management is then needed to avoid potential dangers from it. It differs from a true aneurysm in that it doesn't include any component of the vascular wall, and is not studied as much as a true aneurysm. Here, a model of a femoral pseudoaneurysm was made and a Computational Fluid Dynamics(CFD) simulation was verified with PIV experiment. Afterwards, a CFD simulation with two different models was performed to look for any findings which may help in developing new treatment methods. 相似文献
72.
Organic alkyl and aryl phosphites are effective antioxidants and photostabilizers with applications in a wide range of polymers. The primary role of phosphites is to decompose hydroperoxide. However, aryl phosphites are also capable of reacting as antioxidants by affecting the kinetics. In particular, oligomer‐type phosphites have a greater effect on polymer degradation because of their high compatibility, reactivity, and solubility with almost all polymers. Generally, phosphites are sensitive to hydrolysis. In order to overcome this hydrolytic sensitivity in phosphites, a novel hydrolytically stable oligomeric phosphite incorporating a sterically hindered aromatic alcohol (2,4‐di‐tert‐butyl‐6‐methylphenol) that gives hydrolytic stability to the phosphite was synthesized and characterized, and its performance as an antioxidant for polypropylene was investigated. J. VINYL ADDIT. TECHNOL., 22:146–155, 2016. © 2014 Society of Plastics Engineers 相似文献
73.
Two types of degradable poly(propylene glycol) (PPG) hydrogels that are suitable for the absorption of heavy metals have been presented. The PPG‐O‐P(O)Cl2 fragments obtained by treating hexafunctional PPG with phosphorous oxychloride (POCl3) react with 1,3‐propanediamine (PDA; Gel‐1 ) or PDA together with 1,2‐ethanedithiol ( Gel‐2 ), to yield cross‐linked and water‐swellable hydrogels in a one‐pot method. This protocol for the fabrication of PPG hydrogels exhibits promising advantages over prior methods including a short reaction time, mass‐production, easy separation, and high yield. A series of heavy metal ions were employed to test the adsorptive properties of the hydrogels. Gel‐2 shows better adsorption capacity than Gel‐1 for all the metal ions and the metal ions adsorption efficiency of the two types of hydrogels is in the order of Fe(III) > Pb(II) > Cd(II) > Zn(II) > Cu(II) > Ni(II) > Co(II) > Hg(II). The amounts of metal ions adsorbed increases with metal ion concentration and hydrogel dosage, but decreases with temperature. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40610. 相似文献
74.
75.
Sung Hee Han Bong Soo Ko So Hyun Ahn Dong Ouk Noh Hyung Joo Suh 《International Journal of Food Science & Technology》2017,52(6):1417-1424
We investigated the explosive process effect on antioxidant activities of coffee bean. The total polyphenol contents of powdered extract of explosive puffing coffee bean at 0.75 MPa (PEP 7.5) and powdered extract of explosive puffing coffee bean at 0.9 MPa (PEP 9.0) were at a significantly higher than that of the powdered extract of roasting coffee bean (PER) (P < 0.05). PEP 7.5 showed the highest levels of 3‐CQA (86.23 μg mg?1), 4‐CQA (43.71 μg mg?1), and 5‐CQA (31.66 μg mg?1), and PEP 9.0 had also similar levels of chlorogenic acids, with 3‐CQA (77.99 μg mg?1), 4‐CQA (43.71 μg mg?1), and 5‐CQA (30.32 μg mg?1). PEP 7.5 and PEP 9.0 showed relatively higher antioxidant capacities in DPPH, ABTS, taurine, FRAP, and β‐carotene/linoleic acid assays. PEPs partly recovered the HepG2 cell damage induced by t‐BOOH. These results suggest that puffed coffee has beneficial health effects, and could be used for the development of novel processed coffee products. 相似文献
76.
Hai Hoang Sangmo Kang Yong Kweon Suh 《Journal of Mechanical Science and Technology》2010,24(7):1401-1410
We numerically investigate the effect of the solution-wall (i.e., water-wall and ion-wall) interaction potential on the properties
of confined aqueous solution by using molecular dynamics (MD) simulations. The effect is determined by comparing results obtained
from the MD simulation using the Lennard-Jones (L-J) potential for the water-wall and ion-wall interactions and those using
a purely repulsive potential, i.e., the Weeks-Chandler-Andersen-like potential. In the MD simulations, 680 water molecules
and 20 chloride ions are included between uniformly charged plates that are separated by 2.6 nm. The results show that the
properties of solution are influenced only in the region close to the wall: The water molecules are more densely packed for
the case of the L-J potential. Comparison of the results of the MD simulations in the case of the L-J potential with those
provided by solving the Poisson-Boltzmann equation, we found that classical continuum theory fails to predict the ion density
and electrostatic potential distributions in the region near to the wall, but far way from the wall, the prediction from the
continuum theory is in line with the MD simulation. 相似文献
77.
Joo-Hyun Han Han-Saem Lee Kyung-Do Suh 《Materials science & engineering. C, Materials for biological applications》2011,31(7):1290-1294
Polyvinyl amine (PVAm) hydrogel hollow particles treated by layer-by-layer (LbL) assembly methods were fabricated. The structures of the prepared particles were confirmed through zeta-potential measurements and scanning electron microscopy (SEM). In addition, the loading amount and release rate of Chromotrope 2R (CR) from the prepared particles in each deposition step was investigated. The loading amount had an alternating tendency according to an increase in the layer number. When the outermost layer consisted of poly(sodium 4-styrenesulfonate) (PSS), CR permeation was prevented by ionic repulsion between the PSS and CR. On the other hand, CR easily permeated into the particles when the outermost layer was poly(diallyldimethyl ammonium chloride) (PDDA). The release rate was then changed by ionic interaction between the CR and the cationic polyelectrolyte and by the ionic repulsive force between the CR and the anionic polyelectrolyte. These results indicate that PVAm hydrogel hollow particles treated by the LbL method could potentially be used in the controlled release of water-soluble materials. 相似文献
78.
Chang-Min Suh Sang-Yeob Oh Young-Sik Pyun 《Journal of Mechanical Science and Technology》2010,24(5):1061-1066
This experimental studies were carried out in order to understand the effects of the PVD coating and the UNSM treatment of
HSS55 (high speed steel 55) during the production of the automotive inner pipe by the plastic deformation of S45C. The field
test and the SEM images revealed that the PVD coating is necessary in spite of the high compressive residual stresses which
were formed at the head of a punch pin. Upon the application of the AlCrN coating with the UNSM treatment the productivity
and reliability of a punch pin had improved more than about 2.6 times compared to that of the TiN coating without the UNSM
treatment. It is likely that the improvement is caused by the decreased stress concentration factor by the ‘wrapped in oxides’
inside of an abrasion pit. The abrasion pits were mostly generated within range of 5% ∼ 50% of the diameter ratio from the
end of a pin and reached the maximum value about 17% from the end of a pin. 相似文献
79.
80.
Summary
The new polyarylenevinylene, structurally based on a terstyryl group linked by a maleimide group, was prepared from a new
dibrominated diphenylmaleimide monomer and p-divinylbenzene by Heck-type Pd catalyzed polycondensation. The polymer was soluble in common organic solvents and had M
w and the polydispersity index of 73,600 g/mol and 5.0, respectively. Analysis with IR and NMR indicated that the polymer had
a stereoregular vinylene sequence in the backbone of Z, E, E-configurations in series. The polymer showed optical absorption maximums at 353 nm and 444 nm and the bright orange red-colored
photoluminescence at 570 nm in a solution and 590 nm in a film.
Received: 19 September 2000/Revised version: 4 December 2000/Accepted: 11 December 2000 相似文献