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121.
Zhi Jiang Kenjiro Fukuda Wenchao Huang Sungjun Park Roda Nur Md. Osman Goni Nayeem Kilho Yu Daishi Inoue Masahiko Saito Hiroki Kimura Tomoyuki Yokota Shinjiro Umezu Daisuke Hashizume Itaru Osaka Kazuo Takimiya Takao Someya 《Advanced functional materials》2019,29(6)
Flexible and stretchable organic photovoltaics (OPVs) are promising as a power source for wearable devices with multifunctions ranging from sensing to locomotion. Achieving mechanical robustness and high power conversion efficiency for ultraflexible OPVs is essential for their successful application. However, it is challenging to simultaneously achieve these features by the difficulty to maintain stable performance under a microscale bending radius. Ultraflexible OPVs are proposed by employing a novel metal‐oxide‐free cathode that consists of a printed ultrathin metallic transparent electrode and an organic electron transport layer to achieve high electron‐collecting capabilities and mechanical robustness. In fact, the proposed ultraflexible OPV achieves a power conversion efficiency of 9.7% and durability with 74% efficiency retention after 500 cycles of deformation at 37% compression through buckling. The proposed approach can be applied to active layers with different morphologies, thus suggesting its universality and potential for high‐performance ultraflexible OPV devices. 相似文献
122.
Reverse‐Offset Printed Ultrathin Ag Mesh for Robust Conformal Transparent Electrodes for High‐Performance Organic Photovoltaics
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Zhi Jiang Kenjiro Fukuda Xiaomin Xu Sungjun Park Daishi Inoue Hanbit Jin Masahiko Saito Itaru Osaka Kazuo Takimiya Takao Someya 《Advanced materials (Deerfield Beach, Fla.)》2018,30(26)
Mechanically durable transparent electrodes are needed in flexible optoelectronic devices to realize their long‐term stable functioning, for applications in various fields such as energy, healthcare, and soft robotics. Several promising transparent electrodes based on nanomaterials have been previously reported to replace the conventional and fragile indium‐tin oxide (ITO); however, obtaining feasible printed transparent electrodes for ultraflexible devices with a multistack structure is still a great challenge. Here, a printed ultrathin (uniform thickness of 100 nm) Ag mesh transparent electrode is demonstrated, simultaneously achieving high conductance, high transparency, and good mechanical properties. It shows a 17 Ω sq?1 sheet resistance (Rsh) with 93.2% transmittance, which surpasses the performance of sputtered ITO electrodes and other ultrathin Ag mesh transparent electrodes. The conductance is stable after 500 cycles of 100% stretch/release deformation, with an insignificant increase (10.6%) in Rsh by adopting a buckling structure. Furthermore, organic photovoltaics (OPVs) using our Ag mesh transparent electrodes achieve a power conversion efficiency of 8.3%, which is comparable to the performance of ITO‐based OPVs. 相似文献
123.
A multi-fidelity optimization technique by an efficient global optimization process using a hybrid surrogate model is investigated for solving real-world design problems. The model constructs the local deviation using the kriging method and the global model using a radial basis function. The expected improvement is computed to decide additional samples that can improve the model. The approach was first investigated by solving mathematical test problems. The results were compared with optimization results from an ordinary kriging method and a co-kriging method, and the proposed method produced the best solution. The proposed method was also applied to aerodynamic design optimization of helicopter blades to obtain the maximum blade efficiency. The optimal shape obtained by the proposed method achieved performance almost equivalent to that obtained using the high-fidelity, evaluation-based single-fidelity optimization. Comparing all three methods, the proposed method required the lowest total number of high-fidelity evaluation runs to obtain a converged solution. 相似文献
124.
Katsuaki Suganuma Taira Okamoto Mitsue Koizljmi Masahiko Shimada 《Journal of the American Ceramic Society》1984,67(12):256-C
The internal stress resulting from the thermal expansion mismatch between alumina and steel with and without an interlayer was evaluated. On the basis of the calculation, alumina and steel were bonded using the interlayer method and hot isostatic pressing at 1273 to 1573 K under 100 MPa for 30 min. When a laminated interlayer (niobiumlmolybdenum) was used, a joint with high bonding strength was obtained. 相似文献
125.
In the ultrafiltration test of a myoglobin solution through porous membranes of the ABA-type block copolymers composed of polyamide as outer segments and polyoxyethylene (Mn = 1.9–2.0 × 104) as an inner segment, in which the values of weight fraction of the polyamide segments (W) were 0.90, 0.84, 0.82, 0.81, and 0.73, the concentration of the permeate was found to be much higher than that in feed under the pressure difference of 1–2 kg/cm2. Such singularly facilitated permeation was observed also in the test through the dense membranes of the polyamide–polyoxyethylene block copolymer with W of 0.81 and 0.73. On the other hand, neither porous nor dense membranes of the graft copolymer (W = 0.83) having a dextran stock (Mn = 1.8 × 104) and 2.6 pieces of polyamide branches showed similar facilitated permeation, although dextran was soluble in water as well as polyoxyethylene. The apparent interaction of myoglobin with dextran may be stronger than that with polyoxyethylene. © 1994 John Wiley & Sons, Inc. 相似文献
126.
Keizo Ogino Toshlaki Kakihara Hirotaka Uchiyama Masahiko Abe 《Journal of the American Oil Chemists' Society》1988,65(3):405-411
The effect of oxyethylene groups in a nonionic surfactant on the solution properties of anionicnonionic systems is described;
these systems are sodium dodecyl sulfate (SDS)—hexadecyl polyoxyethylene ethers (C16POEn, where n=10, 20, 30 and 40). The degree of ionic dissociation of the mixed micelles decreases with increasing numbers of
oxyethylene groups in the nonionic surfactant. As polyoxyethylene chain lengths increase, the electrical conductivities of
the mixed surfactant solutions decrease, in spite of the decrease in activation energy for conduction. The radius of the mixed
micelle with the electric double layer is larger for a nonionic surfactant having a shorter polyoxyethylene chain length than
for one having a long polyoxyethylene chain. This may be attributed to the fact that the mixed micelle is formed more easily
by a nonionic surfactant with a shorter polyoxyethylene chain length than by one with a longer chain. 相似文献
127.
Harumi Sato Masahiko Shimoyama Taeko Kamiya Toru Amari Slobodan aic Toshio Ninomiya Heinz W. Siesler Yukihiro Ozaki 《应用聚合物科学杂志》2002,86(2):443-448
Raman spectra have been measured for pellets of five samples of high‐density polyethylene (HDPE), seven samples of low‐density polyethylene (LDPE), and six samples of linear low‐density polyethylene (LLDPE). The obtained Raman spectra have been compared to find out characteristic Raman bands of HDPE, LDPE, and LLDPE. Principal component analysis (PCA) was applied to the Raman spectra in the 1600–650 cm?1 region after multiplicative scatter correction (MSC) to discriminate the Raman spectra of the three different PE species. They are classified into three groups by a score plot of PCA factor 1 vs. 2. HDPE with high density and high crystallinity gives high scores on the factor 1 axis, while LDPE with low density and low crystallinity yields negative scores on the same axis. It seems that factor 1 reflects the density or crystallinity. A PC weight loadings plot for factor 1 shows six upward peaks corresponding to the bands arising from the crystalline parts or all‐trans ? (CH2)n? groups and seven downward peaks ascribed to the bands of the amorphous or anisotropic regions and those arising from the short branches. Partial least‐squares (PLS‐1) regression was applied to the Raman spectra after MSC to propose calibration models that predict the density, crystallinity, and melting points of the polyethylenes. The correlation coefficient was calculated to be 0.9941, 0.9800, and 0.9709 for the density, crystallinity, and melting point, respectively, and their root‐mean‐square error of cross validation (RMSECV) was found to be 0.0015, 3.3707, and 2.3745, respectively. The loadings plot of factor 2 for the prediction of melting point is largely different from those for the prediction of density and crystallinity. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 443–448, 2002 相似文献
128.
Masahiko Shimizu 《International Journal of Wireless Information Networks》2017,24(3):217-224
A millimeter-wave beam multiplexing method using a subarray type interleaved configuration hybrid beamforming with inter-subarray coding is proposed. By multiplexing of adequate directional beams, the proposed method can reduce inter-beam interference and create multiple beams of a theoretical maximum gain that an array antenna can generate. As results of performance comparison in subarray type beamforming with the feasibility, it is shown that channel capacity of the interleaved configuration with inter-subarray coding is larger than that of the localized configuration. Particularly, in user dense environments, the interleaved configuration is effective. Therefore, we think that the interleaved configuration is suitable for millimeter-wave beam multiplexing. 相似文献
129.
In this work, an attempt has been made to synthesize well-distributed stable selenium (Se) particles of nanosize dimensions via an aqueous micellar solution by the assistance of surfactants of two different polarities (anionic, sodium bis(2-ethylhexyl)sulfosuccinate (AOT) and cationic, hexadecyltrimethylammonium bromide (CTAB)). The morphology of the particles was examined with transmission electron microscopy (TEM). X-ray analysis reveals that the particles have a monoclinic structure. The band gap of the particles was determined from UV-visible optical spectroscopic results. The size variation was estimated by employing a quantum confinement effect equation. The evolution of the selenium nanoparticles in AOT and CTAB micellar media was corroborated with the time-dependent absorption spectra. The influence of hydrazine hydrate concentrations on the formation kinetics of Se nanoparticles was also investigated. The capping ability of the surfactants has been quantitatively evaluated from Fourier transform infrared (FTIR) studies. 相似文献
130.
Fluoroalkyl end-capped acrylic acid oligomers/fullerenes nanocomposites reacted smoothly with tetraethoxysilane (TEOS) and silica nanoparticles under alkaline conditions to give fluoroalkyl end-capped oligomers/silica composites-encapsulated fullerenes. Interestingly, these isolated fluorinated composites were found to afford nanometer size-controlled colloidal particles with a good dispersibility in a variety of organic solvents including water. More interestingly, these fluorinated silica nanocomposites-encapsulated fullerenes were applied to a new type of surface modification agent, and these nanocomposites were able to disperse well above the poly(methyl methacrylate) films to exhibit not only surface active property imparted by fluorine but also a unique characteristic related to fullerenes in the nanocomposites on the surface, effectively. 相似文献