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991.
Murai Chizuko; Tanaka Masayuki; Sakagami Masamichi 《Canadian Metallurgical Quarterly》2011,125(2):216
Nonhuman primates, like humans, have demonstrated various physical intuitions. Cacchione and Krist (2004) examined chimpanzees' intuitions about support relations with the violation-of-expectation task. They reported that the chimpanzees possessed intuitions about support, but their intuitions differed from those of humans in part; they were sensitive to “contact/no-contact” and “amount of contact” but not “type of contact” rule. To further explore intuitions about support in nonhuman primates, we conducted similar experiments on monkeys (Japanese monkeys) and apes (chimpanzees). In three experiments, we presented physically possible and impossible events of different support relations to the participants and measured their looking times. The results reveal that the chimpanzees and monkeys detect the violations of “contact/no-contact” and “amount of contact” but not “type of contact” variable. Therefore, the apes and monkeys possess similar intuitions; however, these intuitions differ in part from those of humans. The present study provides new and corroborative evidence of intuitions about support in nonhuman primates. However, this again leads to the question of distinctive understanding about support relations among primate species. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
992.
The fatigue crack growth behavior of an austenitic stainless steel in a vacuum environment has been studied. Fatigue crack
growth tests were performed with the compact tension specimens in laboratory air and vacuum, and the environmental effect
on the crack growth behavior was examined. The crack growth rate data were expressed in terms of the J-integral range during
fatigue loading, while an elastic–plastic finite element analysis was employed to calculate the J-integral range. The fractographic
examinations were also carried out to assess the crack growth mechanisms and correlate with fatigue characteristics. The results
show an accelerated fatigue crack growth in air compared to that in vacuum and this environmental effect depends on the load
ratio. 相似文献
993.
Yoh-Ichiro Ogita Masayuki TachiharaYotaro Aizawa Naoyuki Saito 《Thin solid films》2011,519(14):4469-4472
The passivation effects of AlOx films were investigated for p-type crystalline Si (c-Si) solar cells. The AlOx films were deposited on 10 Ωcm c-Si substrates by catalytic chemical vapor deposition (Cat-CVD) using tri-methyl aluminum (TMA) and O2 at a film temperature of 230 °C. The surface recombination velocity (S0) at the AlOx/Si interface was measured to be below 0.5 cm/s for AlOx films deposited with O2/TMA gas flow-rate ratios of 15-35. This ultra low S0 was achieved primarily by band bending due to the negative interface fixed-charge density (Nf) of an order of 1012 charges/cm2. The decrease in interface trapping density Dit in the negative fixed charge region assists in decreasing S0. 相似文献
994.
Direct measurements of interfacial shear strength of multi-walled carbon nanotube/PEEK composite using a nano-pullout method 总被引:1,自引:0,他引:1
Terumasa TsudaToshio Ogasawara Fei Deng Nobuo Takeda 《Composites Science and Technology》2011,71(10):1295-1300
This paper presents a proposal of a simple and easy method to evaluate the interfacial shear strength (IFSS) of CNT-dispersed polymer composites. An individual multi-wall carbon nanotube (MWNT) was pulled out from a MWNT-dispersed/PEEK composite using a nano-pullout testing system installed in an SEM. The tensile load was measured using the elastic deformation of an AFM cantilever. The pull-out length was controlled by making a through-thickness hole near the specimen edge using a focused ion beam (FIB) system. The IFSS of a MWNT/PEEK composite was measured as 3.5-14 MPa, which agrees with the IFSS estimated from the macroscopic stress-strain behavior of the MWNT/PEEK composites. 相似文献
995.
Prediction of long-term viscoelastic behavior of amorphous resin based on the time-temperature superposition principle 总被引:1,自引:0,他引:1
Masayuki Nakada Yasushi Miyano Hongneng Cai Masato Kasamori 《Mechanics of Time-Dependent Materials》2011,15(3):309-316
This paper deals with the prediction of long-term viscoelastic behavior of amorphous resin at a temperature below the glass
transition temperature T
g
from measuring the short-term viscoelastic behavior at elevated temperatures based on the time-temperature superposition
principle (TTSP) with vertical shift as well as horizontal shift. The long-term creep compliance as well as short-term and
medium-term creep compliances were measured at elevated temperatures. The master curves of creep compliance can be constructed
from measured data by shifting vertically as well as horizontally. The master curves of creep compliance constructed from
measured data by short-term and medium-term creep tests agree well with those measured by long-term creep tests. Furthermore,
the horizontal and vertical shift factors obtained from constructing the master curve are independent of the time period of
creep tests. Therefore, the long-term viscoelastic behavior at a temperature below T
g
can be predicted accurately from measuring the short-term viscoelastic behavior at elevated temperatures based on the TTSP
with vertical shift as well as horizontal shift. 相似文献
996.
Kang S Takeda M Takeguchi M Bae DS 《Journal of nanoscience and nanotechnology》2011,11(12):10800-10803
The precipitation behavior of Cu-Fe alloys with Ni addition on isothermal annealing at 878 K was investigated by means of transmission electron microscopy (TEM), electron dispersive X-ray spectroscopy (EDS), and field-emission scanning electron microscopy (FE-SEM). Magnetic element atoms were segregated from the solid solution in supersaturated state, and nano-scale magnetic particles were randomly formed in the copper matrix at the initial stage of annealing at 873 K. With increasing the isothermal annealing time, however, the striking feature that two or more nano-scale magnetic particles with a cubic shape aligned linearly along (100) directions were observed upon the isothermal annealing at 873 K. To investigate the relationship between micro-structures and magnetic properties of the heterogeneous Cu-Fe-Ni alloys, magnetic measurements such as M-H measurements were also carried out, using a superconducting quantum interference device (SQUID) magnetometer. In this study, it was revealed that the magnetic properties of the specimen presented the ferromagnetic behavior, during the precipitation process in a Cu-Fe-Ni alloy. 相似文献
997.
To enhance the performance of organic photovoltaic (OPV) cells, preparation of organic nanometer-sized pillar arrays is fascinating because a significantly large area of a donor/acceptor heterointerface having continuous conduction path to both anode and cathode electrodes can be realized. In this study, we grew cupper phthalocyanine (CuPc) crystalline nanopillar arrays by conventional thermal gradient sublimation technique using a few-nanometer-sized trigger seeds composed of a CuPc and 3,4,9,10-perylene-tetracarboxylic-dianhydride (PTCDA) stacked layer. We optimized the pillar density by tuning crystal growth condition in order to apply it to OPV cells. 相似文献
998.
Koji Yamada Tai Tsuchizawa Hidetaka Nishi Rai Kou Tatsurou Hiraki Kotaro Takeda 《Science and Technology of Advanced Materials》2014,15(2)
By way of a brief review of Si photonics technology, we show that significant improvements in device performance are necessary for practical telecommunications applications. In order to improve device performance in Si photonics, we have developed a Si-Ge-silica monolithic integration platform, on which compact Si-Ge–based modulators/detectors and silica-based high-performance wavelength filters are monolithically integrated. The platform features low-temperature silica film deposition, which cannot damage Si-Ge–based active devices. Using this platform, we have developed various integrated photonic devices for broadband telecommunications applications. 相似文献
999.
Miyashita K Nishikawa S Beppu F Tsukui T Abe M Hosokawa M 《Journal of the science of food and agriculture》2011,91(7):1166-1174
Obesity and type 2 diabetes are pathologies with rapidly growing prevalence throughout the world. A few molecular targets offer the most hope for anti-obesity and anti-diabetic therapeutics. One of the keys to success will be the induction of uncoupling protein 1 (UCP1) in abdominal white adipose tissue (WAT) and the regulation of cytokine secretions from both abdominal adipose cells and macrophage cells infiltrated into adipose tissue. Anti-obesity and anti-diabetic effects of fucoxanthin, a characteristic carotenoid found in brown seaweeds, have been reported. Nutrigenomic studies reveal that fucoxanthin induces UCP1 in abdominal WAT mitochondria, leading to the oxidation of fatty acids and heat production in WAT. Fucoxanthin improves insulin resistance and decreases blood glucose levels through the regulation of cytokine secretions from WAT. The key structure of carotenoids for the expression of anti-obesity effect is suggested to be the carotenoid end of the polyene chromophore, which contains an allenic bond and two hydroxyl groups. 相似文献
1000.
Takeda M Kitashima K Adachi K Hanaoka Y Suzuki I Koizumi J 《Journal of Bioscience and Bioengineering》2000,90(4):416-421
The gene encoding extracellular poly(3-hydroxybutyrate) depolymerase from a thermophilic poly(3-hydroxybutyrate)-degrading bacterium, strain HS, was cloned and intracellularly expressed in Escherichia coli. The gene was found to consist of 1485-bp nucleotide sequence coding for a 22-amino-acid signal peptide and a 473-amino-acid mature protein. Phylogenetic analysis and domain structure showed that the enzyme was clustered with type II PHB depolymerases. The gene was expressed in E. coli under the control of the tac promoter. A 46-kDa protein was detected in the cell extract by SDS-PAGE. The N-terminal sequence of the protein agreed with that of the original enzyme. The crude enzyme was able to degrade PHB particles at 70 degrees C. 相似文献