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排序方式: 共有2776条查询结果,搜索用时 15 毫秒
41.
42.
Dewu Lin Ying Zhou Kazufumi Kobashi Guohai Chen Don N. Futaba Kenji Hata 《Advanced functional materials》2023,33(8):2211180
Despite 30-year development of carbon nanotube (CNT) based materials, harnessing the outstanding nanoscale properties of individual CNT for macroscale applications remains challenging. High specific surface area, a crucial feature of CNTs, often suffers from the formation of tightly packed bundles with inaccessible “dead space”. Herein, a novel “microwave shock” approach to open the “dead space” trapped within bundles is reported. Employing N2 ambient during microwave irradiation, CNT bundles undergo an efficient structural alteration and interfacial modification simultaneously due to the strong radiative coupling, while the graphitic structure remains undamaged. In this way, a 15-fold increase (from 42 to 648 m2 g−1) in the interstitial surface area as well as the lithiophilic functionalization (≈1 atom% nitrogen doping) are achieved without the degradation of other properties. Furthermore, to highlight the merits of this microwave shock process, the treated CNT films are applied as a host material for the anode in a lithium metal battery and demonstrate the suppression of dendritic lithium growth and improve cycling stability. This microwave shock approach provides an efficient avenue to modify nanocarbon-based materials for further applications. 相似文献
43.
Printed Electronics: Room‐Temperature Printing of Organic Thin‐Film Transistors with π‐Junction Gold Nanoparticles (Adv. Funct. Mater. 31/2014) 下载免费PDF全文
44.
Annealing effects of a high-quality ZnTe substrate 总被引:1,自引:0,他引:1
Kenji Yoshino Minoru Yoneta Kenzo Ohmori Hiroshi Saito Masakazu Ohishi Takayuki Yabe 《Journal of Electronic Materials》2004,33(6):579-582
The sharp photoluminescence (PL) and optical-reflection spectra in the bandedge region of the high-quality nondoped ZnTe substrate
(100) were observed at 4.2 K. Free exciton, associated with lower and upper polaritons (EXL and EXU) at 2.382 eV and 2.381 eV, respectively, were clearly observed. This meant that this substrate was high quality. The intensity
of a bound exciton peak (2.375 eV), which is caused by a Zn vacancy, of a neutral acceptor decreased with an increase of the
Zn vapor pressures. 相似文献
45.
Norihiro Kawasaki Takashi Oozeki Kenji Otani Kosuke Kurokawa 《Solar Energy Materials & Solar Cells》2006,90(18-19):3356-3363
Short-time fluctuations in solar irradiance will become an important issue with regard to future embedded photovoltaic (PV) systems. However, when PV systems are intensively installed, fluctuation of total output in clustered PV systems is not remarkable because there is the smoothing effect of irradiance in certain areas. In this paper, a new estimation method of irradiance fluctuation, which is based on the combination of the Fourier transform and the wavelet transform methods, is described. 相似文献
46.
Preparation and properties of CuInS2 thin film prepared from electroplated precursor 总被引:1,自引:1,他引:1
Yoshio Onuma Kenji Takeuchi Sumihiro Ichikawa Yasunari Suzuki Ryo Fukasawa Daisuke Matono Kenji Nakamura Masao Nakazawa Koji Takei 《Solar Energy》2006,80(1):132-138
Thin CuInS2 films were prepared by sulfurization of Cu/In bi-layers. First, the precursor layer was electroplated onto the treated surface of Mo-coated glass. Observation of the cross-section prepared by focused ion beam (FIB) etching revealed that the void-free film was initially formed on the top surface of the precursor layer and continued to grow until the advancing front of the film reached the Mo layer. The nucleation of voids near the bottom of the CuInS2 film followed. To determine whether the condition of the Cu/In alloy influences the CuInS2 quality we investigated the Cu/In alloy state using FIB. We found that the annealed precursor of low Cu/In ratio (1.2) has several voids in the mid position in the layer compared with Cu-rich precursor (1.6). The cross-sectional view of the Cu-rich absorber layer is uniform compared with the low copper absorber layer. Thin film solar cells were fabricated using the CuInS2 film (Cu/In ratio: 1.2) as an optical absorber layer. It was found that the optimization of a sulfurization period is important in order to improve the cell efficiency. We have not yet obtained good results with high Cu-rich absorber because of a blister problem. This blister was found before sulfurization. So, we are going to solve this blister problem before sulfurization. 相似文献
47.
Meng Yu Tsai Ko Chun Lee Che Yi Lin Yuan Ming Chang Kenji Watanabe Takashi Taniguchi Ching Hwa Ho Chen Hsin Lien Po Wen Chiu Yen Fu Lin 《Advanced functional materials》2021,31(40):2105345
In bionic technology, it has become an innovative process imitating the functionality and structuralism of human biological systems to exploit advanced artificial intelligent machines. Bionics plays a significant role in environmental protection, especially for its low energy loss. By fusing the concept of receptor-like sensing component and synapse-like memory, the photoactive electro-controlled optical sensory memory (PE-SM) is proposed and realized in a single device, which endows a simple methodology of reducing power consumption by photoactive electro-control. The PE-SM is the system built with the stacked atomically thick materials, in which rhenium diselenide serves as a robust photosensor, hexagonal boron nitride serves as a tunneling dielectric, and graphene serves as a charge-storage layer. With the features of the PE-SM, it performs synaptic metaplasticities under optical spikes. In addition, a simulated spiking neural network composed of 24 × 24 PE-SMs is further presented in an unsupervised machine learning environment, performing image recognition via the Hebbian rule. The PE-SM not only improves the neuromorphic computing efficiency but also simplifies the circuit-size structure. Eventually, the concept of photoactive electro-control can extend to other photosensitive 2D materials and provide a new approach of constructing either visual perception memory or photonic synaptic devices. 相似文献
48.
Hiroaki Nakamura Naomichi Hatano Ryōen Shirasaki Naomi Hirayama Kenji Yonemitsu 《Journal of Electronic Materials》2011,40(5):601-605
We consider thermoelectric effects in a pseudo-one-dimensional electron gas (P1DEG) with a spin–orbit interaction (SOI). The
SOI splits the dispersion relation of the P1DEG into subbands with an energy gap. We find quantum oscillations in transport
coefficients, which coincide with the locations of the subband edges, as a function of the electrochemical potential. 相似文献
49.
Extraction of a plasma time-activity curve from dynamic brain PET images based on independent component analysis 总被引:1,自引:0,他引:1
Naganawa M Kimura Y Ishii K Oda K Ishiwata K Matani A 《IEEE transactions on bio-medical engineering》2005,52(2):201-210
A compartment model has been used for kinetic analysis of dynamic positron emission tomography (PET) data [e.g., 2-deoxy-2-18F-fluoro-D-glucose (FDG)]. The input function of the model [the plasma time-activity curve (pTAC)] was obtained by serial arterial blood sampling. It is of clinical interest to develop a method for PET studies that estimates the pTAC without needing serial arterial blood sampling. For this purpose, we propose a new method to extract the pTAC from the dynamic brain PET images using a modified independent component analysis [extraction of the pTAC using independent component analysis (EPICA). Source codes of EPICA are freely available at http://www5f.biglobe.ne.jp/?kimura/Software/top.html]. EPICA performs the appropriate preprocessing and independent component analysis (ICA) using an objective function that takes the various properties of the pTAC into account. After validation of EPICA by computer simulation, EPICA was applied to human brain FDG-PET studies. The results imply that the EPICA-estimated pTAC was similar to the actual measured pTAC, and that the estimated blood volume image was highly correlated with the blood volume image measured using 15O-CO inhalation. These results demonstrated that EPICA is useful for extracting the pTAC from dynamic PET images without the necessity of serial arterial blood sampling. 相似文献
50.
Stefan Schulz Wittko Francke Wilfried A. König Volker Schurig Kenji Mori Rolf Kittmann Dietrich Schneider 《Journal of chemical ecology》1990,16(12):3511-3521
(R)-6-Ethyl-2-methyl-2,3-dihydro-4H-pyran-4-one, (1R,3S,5R)-3-ethyl-1,8-dimethyl-2,9-dioxabicyclo[3.3. 1]non-7-ene, and (1R,3S,5R)-3-ethyl-1,8-dimethyl-2,9-dioxabicyclo[3.3.1]non-7-en-6-one represent the main components in the male pheromone of the swift moth,Hepialus hecta. The amounts of the three components were 40, 5, and 5 g per male, respectively. Structure elucidation of the compounds was based on spectroscopic data as compared to synthetic reference samples. The absolute configurations were determined by gas chromatography on chiral stationary phases; optically active samples served as reference compounds. Electrophysiological and behavioral experiments with natural material and synthetic samples clearly showed the three heterocyclic compounds to act as pheromones. (E, E)--Farnesene represents the main component of the scent secretion of maleHepialus humuli. 相似文献