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Meccanica - The present research focuses on dynamic flow control management using tiny jets with three combinations; the first one located at 90° intervals of the base, the second one located... 相似文献
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Journal of Applied Spectroscopy - With the COVID-19 outbreak, many challenges are posed before the scientific world to curb this pandemic. The diagnostic testing, treatment, and vaccine development... 相似文献
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Nadia Sharif Faiza Saleem Farheen Aslam Shagufta Naz 《Natural product research》2015,29(20):1938-1941
Microalgae have been proposed as a promising source for biodiesel production. Focusing on algal strains for biodiesel production, efforts should be made to search new strains. Experiments were carried out to investigate the effects of growth parameters (nutrients, pH, light, aeration and temperature) and the oil percentage of eight algal strains (Chlorella sp., Cladophora sp., Hydrodictylium sp., Oedogonium sp., Oscillatoria sp., Spirogyra sp., Stigeocolonium sp., Ulothrix sp.). Results show that 6.5–7.5 is the optimum pH for the growth of all algal species. Temperature showed a greater variation (25°40°C). Ulothrix sp. gave more biomass productivity and is the most suitable strain for biodiesel production due to higher oil percentage (62%). Least biomass production was observed for Stigeocolonium sp. and least oil content was obtained from Hydrodictylium sp. It was observed that among these eight algal strains for biodiesel production, Ulothrix and Chlorella are the most promising algae species. 相似文献
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Muhammad Asif Hanif Ahmed Yahya Al-Maskari Jamal Nasser Al-Sabahi Ibtisam Al-Hdhrami Muhammad Mumtaz Khan Ahlam Al-Azkawi 《Natural product research》2015,29(24):2332-2335
Medicago sativa Linn growing in Omani desert were chemically characterised using flame photometry, inductively coupled plasma, gas chromatography–mass spectrometry and high performance liquid chromatographic (HPLC) analysis. HPLC analyses were performed to determine the phenolics and flavonoids present in M. sativa. The major compounds detected in M. sativa leaves were protchaechenic acid (3.22%), hydroxyl benzoic acid (1.05%), β-Phenyl caffate (0.97%) and kaempherol (0.89%). Pterostilbene, a cholesterol-lowering compound, was detected in M. sativa. 相似文献
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Enantioselective and Regiodivergent Functionalization of N‐Allylcarbamates by Mechanistically Divergent Multicatalysis 下载免费PDF全文
Dr. Edward Richmond Ismat Ullah Khan Dr. Joseph Moran 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(35):12274-12277
A pair of mechanistically divergent multicatalytic reaction sequences has been developed consisting of nickel‐catalyzed isomerization of N‐allylcarbamates and subsequent phosphoric‐acid‐catalyzed enantioselective functionalization of the resulting intermediates. By appropriate selection of reaction partners, in situ generated imines and ene‐carbamates are mechanistically partitioned to yield opposing functionalized products. Formal α‐functionalization to give protected α‐arylamines is achieved upon enantioselective Friedel–Crafts reaction with arene nucleophiles, whereas formal β‐functionalization is achieved upon reaction with diarylimine electrophiles in an enantioselective Povarov‐[4+2] cycloaddition. 相似文献
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