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Dr. Raysa Khan Tareque Dr. Storm Hassell-Hart Dr. Tobias Krojer Dr. Anthony Bradley Dr. Srikannathasan Velupillai Dr. Romain Talon Dr. Michael Fairhead Dr. Iain J. Day Kamlesh Bala Dr. Robert Felix Dr. Paul D. Kemmitt Prof. Paul Brennan Prof. Frank von Delft Dr. Laura Díaz Sáez Prof. Kilian Huber Prof. John Spencer 《ChemMedChem》2020,15(24):2513-2520
Combined photochemical arylation, “nuisance effect” (SNAr) reaction sequences have been employed in the design of small arrays for immediate deployment in medium-throughput X-ray protein–ligand structure determination. Reactions were deliberately allowed to run “out of control” in terms of selectivity; for example the ortho-arylation of 2-phenylpyridine gave five products resulting from mono- and bisarylations combined with SNAr processes. As a result, a number of crystallographic hits against NUDT7, a key peroxisomal CoA ester hydrolase, have been identified. 相似文献
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Hypoxia formation and breakdown were tracked during 2015 in Muskegon Lake estuary at multiple locations, and five years (2011–2015) of time-series buoy observatory data were evaluated for the effect of episodic wind-events on lake mixing. Bi-weekly water temperature and dissolved oxygen (DO) profiles at four locations revealed that hypoxia occurred at all sites and persisted for 2–3 months during summer 2015. On one date in late-summer, up to 24% of the lake’s volume was estimated to be mildly hypoxic (DO < 4 mg L?1) as defined by lake sturgeon requirements. Patterns of wind speed and water column stability in late spring indicated that high winds and low stability delayed the onset of hypoxia while in late summer low winds and high stability delayed degradation of hypoxia. Wind speeds appear to play a great role in the interannual variability of stratification and subsequent hypoxia. Water temperature and DO profiles taken before and after one mid-summer mixing event (wind speed >7.7 m s?1 for 10 h), indicated that while the wind was unable to completely mix the entire water column, it deepened the epilimnion by ~1.5 m and sheared a thin layer from the upper hypolimnion. By entraining internally loaded nutrients, such episodic wind-events may initiate and sustain algal blooms in nutrient limited surface waters. Quantifying the variable role of wind and mixing events will be key to integrating limnological processes into climate models of the future. 相似文献
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Alinda Samsuri Mohd Nor Latif Mohd Razali Shamsuddin Fairous Salleh Maratun Najiha Abu Tahari Tengku Shafazila Tengku Saharuddin Norliza Dzakaria Mohd Ambar Yarmo 《International Journal of Hydrogen Energy》2021,46(48):24831-24844
Temperature programmed reduction (TPR) analysis was applied to investigate the chemical reduction progression behavior of molybdenum oxide (MoO3) catalyst. The composition and morphology of the reduced phases were characterized by X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), and field emission scanning electron microscopy (FE-SEM). The reduction progression of MoO3 catalyst was attained with different reductant types and concentration (10% H2/N2, 10% and 20% CO/N2 (%, v/v)). Two different modes of reduction process were applied. The first approach of reduction involved non-isothermal mode reduction up to 700 °C, while the second approach of reduction involved the isothermal mode reduction for 60 min at 700 °C. Hydrogen temperature programmed reduction (H2-TPR) results showed the reduction progression of three-stage reduction of MoO3 (Mo6+ → Mo5+ → Mo4+ → Mo0) with Mo5+ and Mo4+. XRD analysis confirmed the formation of Mo4O11 phase as an intermediate phase followed by MoO2 phase. After 60 min of isothermal reduction, peaks of metallic molybdenum (Mo) appeared. Whereas, FESEM analysis showed porous crater-like structure on the surface cracks of MoO2 layer which led to the growth of Mo phase. Meanwhile, the reduction of MoO3 catalyst in 10% carbon monoxide (CO) showed the formation of unstable intermediate phase of Mo9O26 at the early stage of reduction. Furthermore, by increasing 20% CO led to the carburization of MoO2 phase, resulted in the formation of Mo2C rather than the formation of metallic Mo, as confirmed by XPS analysis. Therefore, the presented study shows that hydrogen gave better reducibility due to smaller molecular size, which contributed to high diffusion rate and achieved deeper penetration into the MoO3 catalyst compared to carbon monoxide reductant. Hence, the reduction of MoO3 in carbon monoxide atmosphere promoted the formation of Mo2C which was in agreement with the thermodynamic assessment. 相似文献
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Li Zhang Huiqun Yuan Sheng-Hung Chang Anthony Lam 《The International Journal of Advanced Manufacturing Technology》2020,107(3):1081-1089
With the continuous development of the Internet of Things technology and the proposal of “Made in China 2025”, the construction of IoT applicat 相似文献
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Carlos Calvo Anthony Mazzei 《世界电子元器件》2006,(3):46-46,48,50,52
精确的RF功率管理是现代无线发射器的热点话题,从基站的功率放大器保护到移动应用中的延长电池使用时间,它都有很多的优点。RF功率监测器,比如对数放大器,允许RF功率测量系统在一个较宽的范围监控和动态调整发射功率。尽管近几年来功率监测的精度已经有了很大改进,但是对于像那些需要高功率发射的应用甚至受到0dB功率监测误差微小变化引起的显著影响。因此这也促使检测器性能不断提高。 相似文献
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