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排序方式: 共有4684条查询结果,搜索用时 15 毫秒
1.
Beierlein Dennis Häussermann Dorothea Traa Yvonne Klemm Elias 《Catalysis Letters》2022,152(10):2908-2919
Catalysis Letters - We developed a rapid aging method for Ni/Al2O3 methanation catalysts mimicking the real aging in the actual application. The method is based on hydrothermal deactivation of the... 相似文献
2.
Qianying Hoo Xiaohu Wang Feng Yuan Xuewei Cao Tiewa Cao Maolin Zhang 《Journal of the European Ceramic Society》2021,41(6):3816-3822
Jingdezhen is famous for its bluish white (Qingbai) porcelains of the Song Dynasty, and those decorated with iron spots are distinctive among them. Herein, iron spots on a bluish white porcelain were investigated using a series of microscopic and spectroscopic characterizations. We found the decreasing iron content from more than 8 wt% to about 2 wt% during the glaze color transition from rusty to brown and finally into green, which built a connection on the coloring mechanism of iron-rich crystallized glaze and celadon glaze. We identified the rare ε-Fe2O3, a promising magnetic material, in both the dark brown crystals and the triangular crystals in the rusty area, which is its first discovery among bluish white porcelains. Based on these findings, we discussed the coloring mechanism of iron-spot decoration along with the physical form of the iron oxide crystals, indicating the partially reducing atmosphere during firing process. 相似文献
3.
Koay Seong Chun Chan Ming Yeng Chou Pui May Tshai Kim Yeow Ong Thai Kiat Cheah Kean How 《乙烯基与添加剂工艺杂志》2020,26(1):10-16
Chrysanthemum flower is among one of the highly sought after and widely planted flower crops, in particular for cultural and religious ceremonies. However, the chrysanthemum stem and stalk have little value and usually discard as by‐product waste from floristry. The objective of this research is to investigate the potential value of utilizing chrysanthemum stem and stalk as reinforcing fillers for thermoplastic composites. In this study, 2‐mm thick composite sheet containing predefined formulations of polylactic acid (PLA), chrysanthemum waste filler (CWF) ranging from 15 to 60 phr, and maleated polyethylene (MAPE) coupling agent up to 5 phr were prepared with the aid of Haake internal mixer and compression molding. The effect of MAPE loading on tensile, thermal, and morphological properties of PLA/CWF composites was investigated. The findings revealed that PLA/CWF composite attained improved tensile modulus compared to the neat PLA, and the tensile modulus increases with higher concentration of CWF. However, both tensile strength and elongation at break reduces with increase loading of CWF. Overall, PLA/CWF composites with MAPE shows better performance compared to those without MAPE, where an optimum strength of 21.8 MPa can be achieved with 60 phr CW and 3 phr MAPE. The measured tensile strength is comparable to alternatives natural fiber thermoplastic composites demonstrating its potential to be used in non‐structurally demanding application. J. VINYL ADDIT. TECHNOL., 26:10–16, 2020. © 2019 Society of Plastics Engineers 相似文献
4.
Corrosion of a salt-coated Ni-superalloy has been studied at 900°C under a wet air and sulfur vapor ambient. The corrosion thickness, after an incubation of ~60 hr, linearly increases with the corrosion time t and the onset of surface spallation occurred at t ≈ 60 hr. The corroded layer consists of a corrosion front dominated by Cr3S4 scales and linear precipitate structures, an inner corrosion layer dominated by Ni3S2 and NiO, and an outer corrosion layer dominated by Al2O3 networks surrounding the Ni3S2 and/or NiO scale structures. The corrosion mechanism is discussed based on the coexistence of H2O, sulfur, and oxygen. 相似文献
5.
Dennis K. J. Lin 《Quality Engineering》2019,31(1):49-59
AbstractThe study of order-of-addition (OofA) experiments is prevalent in many scientific and industrial areas. The statistical design of experiments (DOE) will considerably improve the efficiency of OofA experiments. Designing and modeling the OofA experiments have increasingly received a great deal of attention. In this article, we review the latest work on the design and model of OofA experiments, and introduce some new thoughts. We believe that this article will motivate fruitful applications in real OofA experiments as well as future developments in the methodology. 相似文献
6.
Suk-Young Song Soonil Pyo Sungchul Choi Hee Sang Oh Jung Hwa Seo Ji Hea Yu Ahreum Baek Yoon-Kyum Shin Hoo Young Lee Ja Young Choi Sung-Rae Cho 《International journal of molecular sciences》2021,22(7)
Hypoxic–ischemic encephalopathy (HIE) is a devastating neonatal brain condition caused by lack of oxygen and limited blood flow. Environmental enrichment (EE) is a classic paradigm with a complex stimulation of physical, cognitive, and social components. EE can exert neuroplasticity and neuroprotective effects in immature brains. However, the exact mechanism of EE on the chronic condition of HIE remains unclear. HIE was induced by a permanent ligation of the right carotid artery, followed by an 8% O2 hypoxic condition for 1 h. At 6 weeks of age, HIE mice were randomly assigned to either standard cages or EE cages. In the behavioral assessments, EE mice showed significantly improved motor performances in rotarod tests, ladder walking tests, and hanging wire tests, compared with HIE control mice. EE mice also significantly enhanced cognitive performances in Y-maze tests. Particularly, EE mice showed a significant increase in Cav 2.1 (P/Q type) and presynaptic proteins by molecular assessments, and a significant increase of Cav 2.1 in histological assessments of the cerebral cortex and hippocampus. These results indicate that EE can upregulate the expression of the Cav 2.1 channel and presynaptic proteins related to the synaptic vesicle cycle and neurotransmitter release, which may be responsible for motor and cognitive improvements in HIE. 相似文献
7.
8.
Schurmann Dennis Glavinić Ivan Willers Bernd Timmel Klaus Eckert Sven 《Metallurgical and Materials Transactions B》2020,51(1):61-78
Metallurgical and Materials Transactions B - Flow measurements are performed in a slab model for continuous casting of steel under the influence of a ruler type Electromagnetic Brake (EMBr). The... 相似文献
9.
10.
Daniel Boon Loong Teh Akshaya Bansal Chou Chai Tan Boon Toh Robert Alan Jappy Tucker Gil Gerald Lasam Gammad Yanzhuang Yeo Zhendong Lei Xiang Zheng Fengyuan Yang John S. Ho Nagarjun Bolem Bing Cheng Wu Muthu Kumar Gnanasammandhan Lissa Hooi Gavin Stewart Dawe Camilo Libedinsky Wei-Yi Ong Barry Halliwell Edward Kai-Hua Chow Kah-Leong Lim Yong Zhang Brian K. Kennedy 《Advanced materials (Deerfield Beach, Fla.)》2020,32(29):2001459
Near-infrared (NIR) activatable upconversion nanoparticles (UCNPs) enable wireless-based phototherapies by converting deep-tissue-penetrating NIR to visible light. UCNPs are therefore ideal as wireless transducers for photodynamic therapy (PDT) of deep-sited tumors. However, the retention of unsequestered UCNPs in tissue with minimal options for removal limits their clinical translation. To address this shortcoming, biocompatible UCNPs implants are developed to deliver upconversion photonic properties in a flexible, optical guide design. To enhance its translatability, the UCNPs implant is constructed with an FDA-approved poly(ethylene glycol) diacrylate (PEGDA) core clad with fluorinated ethylene propylene (FEP). The emission spectrum of the UCNPs implant can be tuned to overlap with the absorption spectra of the clinically relevant photosensitizer, 5-aminolevulinic acid (5-ALA). The UCNPs implant can wirelessly transmit upconverted visible light till 8 cm in length and in a bendable manner even when implanted underneath the skin or scalp. With this system, it is demonstrated that NIR-based chronic PDT is achievable in an untethered and noninvasive manner in a mouse xenograft glioblastoma multiforme (GBM) model. It is postulated that such encapsulated UCNPs implants represent a translational shift for wireless deep-tissue phototherapy by enabling sequestration of UCNPs without compromising wireless deep-tissue light delivery. 相似文献