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991.
Robabeh Bagheri Abdul Ghafar Wattoo Yan Yao Jikang Liu Cheng Xu Masoumeh Moradi-Haghighi Zhenlun Song 《International Journal of Hydrogen Energy》2018,43(2):757-771
Developing low-cost, stable, and robust electrocatalysts is significant for high effective hydrogen evolution reaction (HER). In this work, a coating system with Cu2O/NiMoCu on stainless steel (SS) is employed as a highly active and stable catalyst for HER in acidic solutions. Electrochemical measurements for as-designed system on SS show a low onset overpotential, small Tafel slope of ~32 mV/decade and long-term durability over 7 days of HER operation. To further inspections of electrocatalytic behavior of as-prepared system in HER, the EIS measurements are performed at several overpotentials and temperatures. It is found that high hydrogen evolution activity and stability of Cu2O/NiMoCu hybrid is likely due to special morphology of Cu2O which result in large number of active sites for hydrogen adsorption, and a synergetic effect giving electronic structure suitable for the HER. 相似文献
992.
Sabeen Madiha Rehman Zia ur Saeed Faisal Siddiqui Farhan Farooq 《Journal of Materials Science: Materials in Electronics》2022,33(8):4951-4964
Journal of Materials Science: Materials in Electronics - This report presents the VLS synthesis and the study of the charge carrier transport through defect states across the interface in ZnO/In2O3... 相似文献
993.
Mozaffari Saeed Javadi Saman Moghaddam Hamid Kardan Randhir Timothy O. 《Water Resources Management》2022,36(6):1955-1972
Water Resources Management - Forecasting the groundwater level is crucial to managing water resources supply sustainably. In this study, a simulation–optimization hybrid model was developed... 相似文献
994.
Saeed Y. Aghdam Doreswamy Kenchegowda Gregory P. Holmes-Hampton Maria Moroni Sanchita P. Ghosh 《International journal of molecular sciences》2021,22(1)
Following exposure to high doses of ionizing radiation, diverse strains of vertebrate species will manifest varying levels of radiation sensitivity. To understand the inter-strain cellular and molecular mechanisms of radiation sensitivity, two mouse strains with varying radiosensitivity (C3H/HeN, and CD2F1), were exposed to total body irradiation (TBI). Since Insulin-like Growth Factor-1 (IGF-1) signaling pathway is associated with radiosensitivity, we investigated the link between systemic or tissue-specific IGF-1 signaling and radiosensitivity. Adult male C3H/HeN and CD2F1 mice were irradiated using gamma photons at Lethal Dose-70/30 (LD70/30), 7.8 and 9.35 Gy doses, respectively. Those mice that survived up to 30 days post-irradiation, were termed the survivors. Mice that were euthanized prior to 30 days post-irradiation due to deteriorated health were termed decedents. The analysis of non-irradiated and irradiated survivor and decedent mice showed that inter-strain radiosensitivity and post-irradiation survival outcomes are associated with activation status of tissue and systemic IGF-1 signaling, nuclear factor erythroid 2–related factor 2 (Nrf2) activation, and the gene expression profile of cardiac mitochondrial energy metabolism pathways. Our findings link radiosensitivity with dysregulation of IGF-1 signaling, and highlight the role of antioxidant gene response and mitochondrial function in radiation sensitivity. 相似文献
995.
996.
Principal component analysis and correlation studies of spring wheats in relation to cookie making quality 总被引:1,自引:0,他引:1
Shabbir Ahmad Imran Pasha Muhammad Saeed Muhammad Shahid 《International Journal of Food Properties》2017,20(10):2299-2313
Quality of cookies is profoundly influenced by the physicochemical and rheological properties of wheat grains. Therefore, it is pivotal to explore right choice of wheat cultivar. Current study was designed to gauge the relationship between wheat grain physiognomies and flour rheological behaviour with cookie characteristics. The outcomes depicted that selected wheat varieties varied significantly (p < 0.01) in various parameters like thousand kernel weight, test weight, pearling value, Pelshenke and zeleny value. In correlation, particle size index correlated negatively (r = ?0.67) with protein content and positively with water absorption. Spread factor of cookies was influenced by particle size index (r = ?0.63), Pelshenke (r = ?0.62), water absorption (r = ?0.60), and mixographic peak height (r = 0.85). Principal component analysis illustrated that thousand kernel weight, grain length, and width were major components in determining the water absorption of wheat flour. However, spread factor of cookies was partly depicted from Pelshenke value and partly from particle size index. 相似文献
997.
To avoid any interruption of service and considering economic issues, strengthening of existing columns usually occurs while the member is under service loads. One of the important issues being neglected in the redesign process of retrofitted columns is the effects of significant axial load existing in the columns. This paper presents a numerical study to investigate the behavior and the ultimate bearing capacity of box shaped steel columns reinforced with continuous welded plates while under load. In the first phase of the study, it is intended to evaluate the variation of results with respect to the existing design relations. For this purpose, the ultimate bearing capacity of un-preloaded models is assumed to be in accordance with the selected design code and the corresponding geometric imperfection for each model is defined using several analyses to reach the values obtained with the design code, for further studies. In the second phase, the magnitude of initial imperfection is set to 1/500 of the studied columns. In both phases, the effect of magnitude of existing preload on ultimate bearing capacity is investigated considering two influential parameters, namely the slenderness ratio of the column and the ratio between cross sectional area of the column and reinforcing plates. Results show that by increasing the preload magnitude, the ultimate bearing capacity of reinforced columns with identical reinforcing plates, decreases. This reduction is more notable for the columns with median slenderness ratios. However, as the magnitude of preload increases, the effect of slenderness ratio on the reduction of ultimate bearing capacity becomes more evident. Also, it is found that by using a fixed imperfection ratio of L/500, even for un-preloaded models the ultimate bearing capacity of the strengthened column will be less than the values calculated as per the selected design code. Finally, an empirical relation is proposed to calculate reduction of ultimate bearing capacity for columns affected from various preload level considering different slenderness ratios. 相似文献
998.
Proportional navigation (PN) is an effective guidance law in chasing a constant speed target. However, intercepting a maneuvering target requires extra provisions to contain target acceleration. This is observed in the next generation of guidance laws, namely augmented proportional navigation (APN) and the optimal guidance law (OGL). The other advanced guidance method is integral sliding mode (ISM), which exhibits superb low miss distance (MD), but unfortunately at the cost of disappointing effective lateral acceleration (Ceff), higher than the modest level that APN and OGL demand. Reducing both MD and Ceff can be achieved using a multiphase algorithm. A setup of APN, OGL and ISM is proposed to integrate the strength of each and overcome their weaknesses. Hybrid algorithm smooth management is conducted by an optimally tuned fuzzy supervisory controller. The results indicate that in facing a constant acceleration target, an APN‐ISM twin yields the best results, while in case of a constant jerk target an APN‐OGL‐ISM triplet renders excellent interception. Miss distance as low as 0.012m can be achieved with significantly lower control effort than required by ISM alone. The simulations results confirm the conclusions and illustrate the capacity of the algorithm in combating maneuvering targets. 相似文献
999.
In a medium consisting of triethylamine and water, α-methylene ketones undergo room temperature Gewald reactions with elemental sulfur and ethyl cyanoacetate (or malononitrile) to yield 2-aminothiophene derivatives efficiently within short time periods. Because of the high polarity of the medium, products precipitate in the reaction mixtures spontaneously. This makes isolation of the products easy by simple filtration and avoids cumbersome chromatographic separations. Mechanistic studies suggest that the reactions proceed via a Knoevenagel condensation pathway. 相似文献
1000.
As disruptive technologies like Industry 4.0 and Internet of Things advance at a breakneck speed, modern manufacturing is ready to embrace the systematic deployment of predictive production systems. The predictive production system is an intelligent manufacturing system where networked assets are equipped with self-awareness to predict, root cause, and reconfigure faulty events automatically. Cyber physical systems are one of the core enabling technologies within which information from all the related perspectives are analyzed and interconnected between physical factory floor and the cyber computational space. It intertwines with smart analytics to comprehend invisible issues for rapid decision making. In this paper, a systematic approach is proposed on how cyber physical systems can be applied to predictive production systems to inject resilience and interoperability so that the productivity of manufacturing can be optimized. 相似文献