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121.
Masato Takeuchi Junichi Deguchi Manabu Hidaka Shiro Sakai Kyoungja Woo Pyuck-Pa Choi Jong-Ku Park Masakazu Anpo 《Applied catalysis. B, Environmental》2009,89(3-4):406-410
The photocatalytic oxidation of gaseous acetaldehyde with O2 on commercial TiO2 nano-particles could be successfully enhanced by a simple mechanical blending with a high-silica mordenite (MOR) zeolite, the surface of which showed high hydrophobic properties. When the TiO2 nano-particles of ca. 5–20 wt% were mixed with the MOR zeolite powders in an agate mortar for only 5 min, the blended TiO2/MOR samples showed higher photocatalytic reactivity as compared to the pure TiO2 nano-particles. Since the high-silica zeolite powders are highly transparent in UV light regions, the incident UV light is effectively irradiated onto the whole part of the TiO2 nano-particles without any loss of light intensity. Furthermore, the siliceous MOR zeolite powders effectively adsorb the gaseous acetaldehyde molecules and supply them onto the surfaces of the blended TiO2 nano-particles, resulting in an enhancement of the photocatalytic reactivity. 相似文献
122.
Clogging of venting slots in injection molds is a common maintenance problem caused by the degradation and the accumulation of gaseous and volatiles by-products of polymer melting. In this work, the effect of laser-induced periodic surface structures on the self-cleaning properties of venting slots is investigated. The degradation of poly(ethylene terephthalate) (PET) over different surfaces is characterized by reproducing the mechanisms that occurs in mold cavities when the air is pushed through the venting channel. An imaging technique is developed for the quantification of the sediment that deposits on sample surfaces due to condensation of by-products of PET melting. The experimental results indicate that the use of a multiscale texture minimizes the deposition of residues on the vent surface reducing it from 17.2 to 3.1%. A linear dependency between contact angle and clogging ratio indicates the efficacy of the model that explains vent self-cleaning properties considering their wetting properties. 相似文献
123.
Sensitivity of charged particle activation analysis for long-lived radioactive nuclide determination
Masumi Oshima Yurie Yamaguchi Masato Asai Kazuaki Tsukada Jun Goto Shigeru Bamba 《Journal of Nuclear Science and Technology》2019,56(9-10):866-872
ABSTRACTCharged Particle Activation Analysis (CPAA) utilizing an 8-MeV proton beam has been studied for determination of 35 long-lived radioactive nuclides. We accumulated the reaction cross section and nuclear decay data by referring to nuclear database supplied by National Nuclear Data Center in Brookhaven National Laboratory. We also calculated the reaction cross sections by using statistical model code ALICE. By using the nuclear data, we have derived determination sensitivity of the radioactive nuclides relative to unit weight and specific radioactivity. The result indicates that several hardly measurable nuclides with long half-lives such as 135Cs, 244Pu, 129I, 126Sn, 93Mo, 107Pd, 236U, 248Cm, and 237Np have high sensitivity. It may be concluded that CPAA can be applied to determination of several long-lived nuclei and will provide a quick and non-destructive analysis method. 相似文献
124.
125.
Saito Ken Inoue Chikara Ikegawa Jin Yamazaki Kazuhiko Goto Sota Takamura Masato Mihara Shunsuke Suzuki Shinsuke 《Metallurgical and Materials Transactions A》2020,51(9):4499-4510
Metallurgical and Materials Transactions A - In this study, we investigated the effects of the size and distribution of spheroidized cementite on the characteristics of a punched surface as well as... 相似文献
126.
Zijing Wang Fen Wang Angga Hermawan Yusuke Asakura Takuya Hasegawa Hiromu Kumagai Hideki Kato Masato Kakihana Jianfeng Zhu Shu Yin 《材料科学技术学报》2021,73(14):128-138
Acetone,as widely used reagents in industry and laboratories,are extremely harmful to the human.So the detection of acetone gas concentrations and leaks in special environments at room temperature is essential.Herein,the nanocomposite combining SnO-SnO2 (p-n junction) and Ti3C2Tx MXene was successfully synthesized by a one-step hydrothermal method.Because of the existence of a small amount of oxygen during the hydrothermal conditions,part of the p-type SnO was oxidized to n-type SnO2,forming in-situ p-n junctions on the surface of SnO.The hamburger-like SnO-SnO2/Ti3C2Tx sensor exhibited improved acetone gas sensing response of 12.1 (Rg/Ra) at room temperature,which were nearly 11 and 4 times higher than those of pristine Ti3C2Tx and pristine SnO-SnO2,respectively.Moreover,it expressed a short recovery time (9 s) and outstanding reproducibility.Because of the different work functions,the Schottky barrier was formed between the SnO and the Ti3C2Tx nanosheets,acting as a hole accumulation layer (HALs) between Ti3C2Tx and tin oxides.Herein,the sensing mechanism based on the formation of hetero-junctions and high conductivity of the metallic phase of Ti3C2Tx MXene in SnO-SnO2/Ti3C2Tx sensors was discussed in detail. 相似文献
127.
Taehwan Jun Junghwan Kim Masato Sasase Hideo Hosono 《Advanced materials (Deerfield Beach, Fla.)》2018,30(12)
Transparent amorphous semiconductors (TAS) that can be fabricated at low temperature are key materials in the practical application of transparent flexible electronics. Although various n‐type TAS materials with excellent performance, such as amorphous In‐Ga‐Zn‐O (a‐IGZO), are already known, no complementary p‐type TAS has been realized to date. Here, a material design concept for p‐type TAS materials is proposed utilizing the pseudo s‐orbital nature of spatially spreading iodine 5p orbitals and amorphous Sn‐containing CuI (a‐CuSnI) thin film is reported as an example. The resulting a‐CuSnI thin films fabricated by spin coating at low temperature (140 °C) have a smooth surface. The Hall mobility increases with the hole concentration and the largest mobility of ≈9 cm2 V?1 s?1 is obtained, which is comparable with that of conventional n‐type TAS. 相似文献
128.
Shibnath Samanta Miryala Muralidhar V. Sankaranarayanan K. Sethupathi M. S. Ramachandra Rao Masato Murakami 《Journal of Materials Science》2017,52(22):13012-13022
Nb and Fe co-doped PLZT (Pb0.97La0.02(Zr0.52Ti0.48)1?2x (Nb0.5Fe0.5)2x O3 for x = 0.00, 0.02, 0.04, 0.06 and 0.08) samples have been prepared using sol–gel method. X-ray diffraction (XRD) and Raman spectroscopy studies confirmed that the samples are single phase even for the highest tested doping of 8 mol% of Nb and Fe. Incorporation of Nb and Fe atoms into PLZT lattice has been confirmed by XRD study where a systematic peak shift has been observed with increasing dopant concentration. The lattice parameters are found to decrease gradually with increase in Nb and Fe contents. From Raman spectroscopic investigation, redshift of several modes has been observed. Rietveld refinement has been performed to correlate XRD results with the fitting of Raman spectra. A total of 14 distinguished modes have been identified by de-convolution of Raman spectra, and they are in good agreement with the theoretically calculated modes for PbTiO3 and also with those reported on PZT and PLZT previously. The Burstein–Moss shift of absorption edge has been observed by diffuse reflectance spectroscopy experiment, and the analysis shows change in band gap from 3.21 eV (for x = 0.00) to 2.59 eV (for x = 0.08). The underlying mechanisms and the observed electronic behavior have been confirmed and analyzed by photoluminescence study which revealed several transitions and supported the effect of Nb and Fe co-doping as observed from XRD and Raman spectroscopy. 相似文献
129.
Tsutomu Kanno Hiromasa Tamaki Masato Yoshiya Hiroshi Uchiyama Sachiko Maki Masaki Takata Yuzuru Miyazaki 《Advanced functional materials》2021,31(13):2008469
Mg3Sb2-based intermetallic compounds with exceptionally high thermoelectric performance exhibit unconventional n-type dopability and anomalously low thermal conductivity, attracting much attention to the underlying mechanisms. To date, investigations have been limited to first-principle calculations and thermodynamic analysis of defect formation, and detailed experimental analysis on crystal structure and phonon modes has not been achieved. Here, a synchrotron X-ray diffraction study clarifies that, against a previous view of a simple crystal structure with a small unit cell, Mg3Sb2 is inherently a heavily disordered material with Frenkel defects, charge-neutral defect complexes of cation vacancies and interstitials. Ionic charge neutrality preserved in Mg3Sb2 is responsible for exotic n-type dopability, which is unachievable for other Zintl phase materials. The thermal conductivity of Mg3Sb2 exhibits deviation from the standard T−1 temperature dependency with strongly limited phonon transport due to a strain field. Inelastic X-ray scattering measurement reveals enhanced phonon scattering induced by disorder. The results will draw renewed attention to crystal defects and disorder as means to explore new high-performance thermoelectric materials. 相似文献
130.
Yoshihisa Kosugi Masato Goto Zhenhong Tan Asaya Fujita Takashi Saito Takashi Kamiyama Wei-Tin Chen Yu-Chun Chuang Hwo-Shuenn Sheu Daisuke Kan Yuichi Shimakawa 《Advanced functional materials》2021,31(25):2009476
Materials which show novel thermal properties can be used to make highly efficient and environmentally friendly energy systems for thermal energy storage and refrigeration through caloric effects. An A-site-ordered quadruple perovskite-structure oxide, NdCu3Fe4O12, is found to release significant latent heat, 25.5 kJ kg−1 (157 J cc−1), at the intersite-charge-transfer transition temperature near room temperature. The transition is first-order and accompanied by an unusual magnetic ordering and a large negative-thermal-expansion-like volume change, and thus, it causes a large entropy change (84.2 J K−1 kg−1). The observed entropy change is comparable to the largest changes reported in inorganic solid materials, and more importantly, it is utilized through a colossal barocaloric effect. The adiabatic temperature change by applying 5.1 kbar pressure is estimated to reach 13.7 K, which means efficient refrigeration can be realized through this effect. 相似文献