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741.
Weifeng Wei Mehmet Egilmez Weixing Chen Jan A. Jung Douglas G. Ivey 《Journal of Materials Science》2010,45(24):6824-6829
The rock salt-to-spinel structural transformation that occurs in anodically electrodeposited Mn–Co–O nanocrystals involves
a rearrangement of Mn/Co cations from octahedral interstices to tetrahedral interstices. The cation ordering process leads
to distinct magnetic properties. Curie temperature (T
C) and blocking temperature (T
B) increase dramatically with annealing temperature (200–400 °C), while the corresponding change in particle size for the oxide
nanocrystals is rather small. A strong correlation between the magnetic properties and the cation ordering degree in annealed
Mn–Co–O nanocrystals was established. These unique magnetic properties can be attributed to the magnetic moment changes induced
by Mn/Co cation ordering from octahedral interstices to tetrahedral interstices in the annealed Mn–Co oxide nanocrystals. 相似文献
742.
Caulerpa lentillifera inhibits protein-tyrosine phosphatase 1B and protects pancreatic beta cell via its insulin mimetic effect 总被引:1,自引:0,他引:1
Food Science and Biotechnology - The aim of this study was to determine whether Caulerpa lentillifea extract (CLE) can protect pancreatic beta cells and enhance insulin signaling in adipocytes. We... 相似文献
743.
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
744.
This paper addresses the use of composite bone plates in healing long-bone fractures such as transverse fractures of the tibia using finite element analysis, that takes into consideration contact conditions and material property variations of calluses in relation to the healing period. For the time-varying properties of calluses in relation to the healing period, stepwise material properties were imposed on the callus part based on the time elapsed, and the loading conditions were coupled with the callus properties based on the length of the healing period. The strain distributions at the fracture site were calculated according to the stacking sequence of the bone plate and healing time. The analysis results showed that composite bone plates with stacking sequences of [0]12T for the Kevlar/BCP composites generated the most appropriate strain distributions at the fracture site during the early healing process. 相似文献
745.
Gun Joo Jung Sung Ki Song Young Chull Ahn Geun Sug Oh Young Bin Im 《Journal of Mechanical Science and Technology》2011,25(2):503-512
This research has investigated physical variables affecting indoor thermal comfort and subjective responses of thermal comfort
of students in a university in Korea in which the weather is oceanic temperate climate, and has been performed to contribute
to the research fields of Sustainable Thermal Standard and Adaptive Thermal Comfort (ATC). This research is based on the ISO
7730-2005 standard and the ATC theories and 4 main variables of PMV such as dry bulb temperature (Ta), relative humidity (RH),
black bulb temperature (Tg), and air velocity (Va) are measured once a week during two regular semesters. A clothing insulation,
a thermal sensation vote (TSV), an acceptability of thermal environment, and a preference for cooling and heating are investigated
at the same time using a questionnaire. This study was carried out for 26 weeks during the spring season, from March to June
2009, and the autumn season, from September to December 2009. The main achievements of this study are as follows. Monthly
Mean Outdoor Temperature (MMOT) and Operative Temperature (OT) in the classroom during research periods are 7.4∼23.3°C and
17.5∼29.0°C, respectively. The acceptability ratio of thermal environment shows over 80% when the range of OT in the classroom
is 17∼25°C, and the range can be applicable to operative index of heating and cooling of classroom. The mean TSV of respondents
is almost “neutral (0)” when the PMV in the classroom moves to “neutral (0)” and “slightly cool (−1)”, and the TSV is almost
“+1.5” when the PMV moves to “slightly warm (+1)”. The acceptability ratio of thermal environment is slightly different from
ASHRAE Standard 55-2004. So it is necessary to more investigate standard range of acceptability of thermal environment in
oceanic temperate climate region using much more databases. 相似文献
746.
Quasi-isotropic bending responses of metallic sandwich plates with bi-directionally corrugated cores
In order to reduce anisotropic behaviors of sandwich plates with open channel cores under the bending load, bi-directionally corrugated cores were introduced. Bi-directionally corrugated core has two additional design parameters related with a corrugation pass than uni-directionally corrugated core, so that its properties with respect to core orientations can be controlled. Sandwich plate with bi-directionally corrugated core is designed optimally so that beam buckling of face sheets is reduced drastically and anisotropic buckling behavior in the face sheets is minimized. The cores fabricated by a sectional forming process were bonded with face sheets by adhesive bonding. Three-point bending experiments were carried out with respect to core orientations. It has been shown from the experiments that sandwich plates with bi-directionally corrugated cores exhibit quasi-isotopic bending behaviors and structural performances in sandwich plates. 相似文献
747.
Arsen Babajanyan Harutyun Melikyan Jerome Carnis Youngwoon Yoon Hanju Lee Hyung Keun Yoo Kiejin Lee Barry Friedman 《Synthetic Metals》2011,161(11-12):931-936
Direct probing of the conductivity distribution in organic materials is motivated by the need to obtain a deeper understanding of carrier behavior in organic thin-film transistors (OTFT), organic electro-luminescent devices, organic photoconductors, and organic biosensors. Here we used a near-field scanning microwave microscope to visualize conductivity profiles in OTFT channel. Applying this technique to pentacene field-effect transistors has revealed changes of the conductivity distribution in the channel arising from the development and exhaustion of an accumulated charge region. The electric field profiles, the complementary image of conductivity profiles, which are visualized by using an optical second harmonic generation method, support the results. We anticipate that direct observation by this microwave method will find wide application in measurement of carrier conductivity in organic and nonorganic materials. 相似文献
748.
The present paper (Part II) is a sequel to the previous paper (Part I) [Paik JK, Seo JK. Nonlinear finite element method models for ultimate strength analysis of steel stiffened-plate structures under combined biaxial compression and lateral pressure actions—Part I: Plate elements. Thin-Walled Struct 2008, this issue, doi:10.1016/j.tws.2008.08.005.] on the application of nonlinear finite element methods for ultimate strength analysis of steel stiffened-plate structures under combined biaxial compression and lateral pressure actions. In contrast to Part I dealing with plate elements, the present paper (Part II) treats stiffened panels surrounded by strong support members such as longitudinal girders and transverse frames. In similar to Part I, some important factors of influence such as structural dimensions, initial imperfections, loading types and computational techniques in association with ultimate limit states are studied. Some useful insights in terms of nonlinear finite element method modeling are developed using ANSYS code together with the ALPS/ULSAP semi-analytical method, the latter being for the purpose of a comparison. 相似文献
749.
Optically pure poly(lactic acid) (PLA) was obtained from lactic acid via purification of the corresponding lactide. The optical purity of PLA was determined using polarimetry and NMR. In the depolymerization
process, the effect of the reaction conditions and catalysts on optical purity of the lactide was examined with temperature
having a significant effect. In addition, the degree of racemization increased with increasing molecular weight of the oligomeric
PLA. The effects of temperature, time, solvent, and stirring speed (RPM) on the lactide purification process were examined
in order to improve optical purity. Optical purity was maximized when separation was carried out at 25 °C. The optical purity
of PLA was significantly affected by that of lactide used. 相似文献
750.
Hee Mun Park Ji Young Choi Hyun Jong Lee Eui Yoon Hwang 《Construction and Building Materials》2009,23(1):219-225
This paper describes the results of laboratory and full-scale performance tests for a high durability asphalt binder (HDAB) and high durability asphalt mixture (HDAM) applicable to the wearing course in a bridge deck system. The HDAB was developed using a styrene–butadiene–styrene (SBS) modifier and hydrocarbon for improving construction workability and resistance to fatigue cracking. Various binder tests were conducted on the HDAB, and test results showed that the resistance to fatigue and low temperature cracking of the HDAB increased significantly compared to that of the PG 64-22 and PG 76-22 binders. For the mixtures, the fatigue test results showed that the HDAM has a three times longer fatigue life than the SBS-modified asphalt mixture. It was also found that the HDAM has a higher resistance against moisture-induced damage. Results from full-scale accelerated testing on the bridge deck pavement system proved that the HDAM can significantly improve pavement performance. 相似文献