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排序方式: 共有277条查询结果,搜索用时 15 毫秒
71.
72.
73.
Ban-Seok JeongHyunbong Choi Nara ChoHaye Min Ko Woocherl LimKihyung Song Jae Kwan Lee Jaejung Ko 《Solar Energy Materials & Solar Cells》2011,95(7):1731-1740
New symmetrical low band-gap small molecule materials, DPP-bis[ter-3HT-TPA] and DPP-bis[ter-3HT] as novel derivatives of Diketopyrrolopyrrole-thiophene with/without triphenylamine (TPA) end group have been synthesized and characterized. And the effects of TPA moiety were investigated. Compared to DPP-bis[ter-3HT], DPP-bis[ter-3HT-TPA] shows red-shifted absorption and significantly higher molar absorption coefficient. And the HOMO level of DPP-bis[ter-3HT-TPA] is elevated than DPP-bis[ter-3HT]. Moreover, DPP-bis[ter-3HT-TPA] exhibited one order higher hole mobility than DPP-bis[ter-3HT], suggesting that TPA contributes to a better hole mobility. The bulk-heterojunction photovoltaic devices with DPP-bis[ter-3HT-TPA] showed better efficiencies than DPP-bis[ter-3HT], showing the best power-conversion efficiency (PCE) of 1.5% (±0.12) under 100 mW/cm2 with a short-circuit current (Jsc)=5.73 mA/cm2, a fill factor (FF)=0.45, and an open-circuit voltage (Voc)=0.59 mV. 相似文献
74.
Thuy T. T. Thành Hidekazu Yasunaga Ryo Takano Hiroshi Urakawa Kanji Kajiwara 《Polymer Bulletin》2001,47(3-4):305-312
Summary New series of tri-sulfated (τ-carrageenan) and tetra-sulfated (ρ-carrageenan) carrageenans were prepared by the sulfating reaction from ι-carrageenan. The chain conformations of new carrageenans in aqueous solutions were investigated in the presence of various metal salts by means of static/dynamic light scattering and small-angle X-ray scattering, and their conformational characteristics were discussed with respect to the gelation behaviour. Although the overall conformation of newly prepared carrageenans is specified as a random coil, the local chain retains a rigid-rod-like structure by forming a helical conformation. The sulfate groups on C2 of (1→3)-linked β-D-galactoses were found primarily responsible to prevent gelation. Received: 28 August 2001/Accepted: 17 September 2001 相似文献
75.
T. Sonoda M. Kinoshita M. Sataka K. Yasunaga 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2010,268(19):3277-3281
In order to understand the properties of ion tracks and the microstructural evolution under accumulation of ion tracks in UO2, 100 MeV Zr10+ and 210 MeV Xe14+ ions irradiation examinations have been done at a tandem accelerator facility of JAEA-Tokai, and it has been observed the microstructure by means of a transmission electron microscope (TEM) and a scanning electron microscope (SEM) in CRIEPI.Comparison of the diameter of ion tracks between UO2 and CeO2 under irradiation with 100 MeV Zr10+ and 210 MeV Xe14+ ions at room temperature clarify that the sensitivity on high density electronic excitation of UO2 is much less than that of CeO2. By the cross-sectional observation of UO2 under irradiation with 210 MeV Xe14+ ions at 300 °C, elliptical changes of fabricated pores that exist till ∼6 μm depth and the formation of dislocations have been observed in the ion fluence over 5 × 1014 ions/cm2. The drastic changes of surface morphology and inner structure in UO2 indicate that the overlapping of ion tracks will cause the point defects, enhance the diffusion of point defects and dislocations, and form the sub-grains at relatively low temperature. 相似文献
76.
Kim J.H. Sarin S.V. Yasunaga M. Oh H. 《Vehicular Technology, IEEE Transactions on》2001,50(1):278-286
We are proposing a new noncoherent pseudonoise code acquisition method for code-division multiple-access (CDMA) mobile communication systems. The proposed method employs two digital matched filters, and the code acquisition is based on a double dwell process. Through serial cascading of the dual-matched filters, the proposed code acquisition method does not lose the track of the incoming sequence even after returning from the false alarm state. This unique feature imparts on our design much desired stability. Moreover, the use of two matched filters increases the acquisition speed, which is of prime importance. One important issue in CDMA acquisition is how to determine the threshold values for optimal performance, the measure of optimality being the minimum mean acquisition time. In our performance analysis, we have derived the probability of detection and false alarm as a function of threshold values, then determine the threshold values that achieve the minimum mean acquisition time. Our performance analysis shows that the mean acquisition time is 35 ms at -15 dB input chip signal-to-noise ratio, much faster than the conventional active correlation technique 相似文献
77.
Naoki Koizumi Kazuya Hayashi Moritoshi Yasunaga Kunihito Yamamori Ikuo Yoshihara 《Artificial Life and Robotics》2008,12(1-2):214-218
Waveform distortion is a serious problem in higher-frequency signals on printed circuit boards (PCBs). To overcome this problem,
we have already proposed the segmental transmission line (STL) method, which divides transmission lines into several segments
with different line widths. Each line width is adjusted to make the reflection noises cancel each other out in order to minimize
the signal distortion. In this research, we first analyze the waveform reshaping mechanism of STL. Next, we apply STL to a
dual in-line memory module (DIMM) clock-line for high-speed computers. The results give helpful guidelines for STL designs,
which shows the efficiency of STL.
This work was presented in part at the 12th International Symposium on Artificial Life and Robotics, Oita, Japan, January
25–27, 2007 相似文献
78.
Hiromi Sato Shintaro Narita Masanori Ishida Yoshiko Takahashi Huang Mingguo Soki Kashima Ryohei Yamamoto Atsushi Koizumi Taketoshi Nara Kazuyuki Numakura Mitsuru Saito Toshiaki Yoshioka Tomonori Habuchi 《International journal of molecular sciences》2022,23(4)
Lard diet (LD) is a risk factor for prostate cancer (PCa) development and progression. Two immunocompetent mouse models fed with isocaloric specific fat diets (LD) enriched in saturated and monounsaturated fatty acid (SMFA), showed significanftly enhanced PCa progression with weight gain compared with a fish oil diet (FOD). High gut microbial divergency resulted from difference in diets, and the abundance of several bacterial species, such as in the orders Clostridiales and Lactobacillales, was markedly altered in the feces of LD- or FOD-fed mice. The proportion of the order Lactobacillales in the gut was negatively involved in SMFA-induced body weight gain and PCa progression. We found the modulation of lipid metabolism and cholesterol biosynthesis pathways with three and seven commonly up- and downregulated genes in PCa tissues, and some of them correlated with the abundance of the order Lactobacillales in mouse gut. The expression of sphingosine 1-phosphate receptor 2, which is associated with the order Lactobacillales and cancer progression in mouse models, was inversely associated with aggressive phenotype and weight gain in patients with PCa using the NCBI Gene Expression Omnibus database. Therefore, SMFA may promote PCa progression with the abundance of specific gut microbial species and overexpression of lipogenic genes in PCa. Therapeutics with alteration of gut microbiota and candidate genes involved in diet-induced PCa progression may be attractive in PCa. 相似文献
79.
Several studies in animals and humans have reported beneficial effects of diacylglycerol (DAG) on lipid and energy metabolism. We assessed the effect of DAG versus triacylglycerol (TAG) treatment on total energy expenditure (TEE), total fat oxidation (Fox) and respiratory quotient (RQ), and measured the oxidation rate of each oil using a respiratory chamber and the 13C-stable isotope. Eleven healthy subjects participated in a double-blind, randomized crossover study. Subjects consumed an energy maintenance diet consisting of 55% of total calories from carbohydrate, 15% from protein and 30% from fat during both the 3-day pre-chamber and 36-h chamber period. Fifty percent of the fat was test oil, containing either DAG oil or TAG oil. The oxidation rate of ingested test oils was determined by monitoring 13CO2 excretion in the breath from 13C-labeled diolein or 13C-labeled triolein. There were no significant differences in TEE, RQ and total Fox between the DAG and TAG treatment in the overall analysis. In the subgroup analysis, DAG treatment decreased RQ significantly in subjects with a high fat ratio (HFR) compared to TAG treatment. In addition, ingested diolein oxidation in DAG treatment was significantly faster than triolein oxidation in TAG treatment in the HFR group. Enhanced fat utilization with DAG treatment and rapid oxidation of ingested DAG may, at least in part, explain the greater loss of body weight and body fat related to DAG consumption found in the weight-loss studies. 相似文献
80.
When potato starch was hydrolyzed to form Nägeli amylodextrin by 16% sulfuric acid at 30°C, only the amorphous portion of the starch granules was deteriorated. The crystallinity of Nägeli amylodextrin showing the hydrolysis ratio of 0.22 was 1.28 times as large as that of original starch. The hydrolysis process at above 45°C was given by two exponential equations. The value of acid resistance portion (Co) at 30 and 38°C was 100%, while the values at 45, 50 and 55°C were 67, 38 and 18%, respectively. The high value of Co generally showed the high acid resistance in the various starches. Sweet potato and waxy rice starches were more easily hydrolyzed than other starches, although they gave the relatively high value of Co. Thus, it was slightly more difficult for low acid resistance portion of potato starch to be hydrolyzed than for that of other starches. Moreover, that of waxy rice was easily hydrolyzed. 相似文献