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81.
Taira H Aoki S Yamanoha B Taguchi S 《Journal of photochemistry and photobiology. B, Biology》2004,75(3):145-155
Sudden exposure experiments to high PAR (photosynthetically available radiation) or high PAR+UVR (ultraviolet radiation) were conducted for the marine dinoflagellate Scrippsiella sweeneyae acclimated to either low PAR or high PAR to determine the induction of cellular mycosporine-like amino acid (MAA) in relation to photosynthesis status. When the exposure to high PAR (30.8 Wm(-2)) was provided at different time in the light period for S. sweeneyae acclimated to low PAR (7.7 Wm(-2)) which suppressed photosynthesis, S. sweeneyae could enhance the induction of MAA but it only occurred in the first half of the light period. When UVR exposure was provided for the culture acclimated to high PAR which enhanced photosynthesis, cellular MAA content did not increase during the entire light period, but displayed daily variation similar to the control for two and half days. Daily variation of cellular MAA content did not synchronized with that of cell volume and cellular chlorophyll a content. The individual MAAs also revealed similar daily variations with different phase, which increased for a few hours in the beginning of the light period, except for cellular palythine content. Thus the total cellular MAA content revealed daily variation with changing the relative composition within a few hours. As one of the biological protective strategies against harmful UVR in sunlight, the daily vertical migration in the bloom forming dinoflagellates might be accompanied by the daily variation of cellular MAA content for a photosynthesis at daytime. 相似文献
82.
When milled together with bismuth shots, nitroarenes are readily converted to azoxy- and/or azoarenes depending on substrates and conditions employed. Simple extraction with organic solvent followed by evaporation of the resulting dark pasty solid gave the product in good yield. 相似文献
83.
Funabiki T Sugio D Inui N Maeda M Hitomi Y 《Chemical communications (Cambridge, England)》2002,(5):412-413
Catechol dioxygenase model oxygenations have been performed for the first time in water by using water-soluble nonheme iron(III) complexes, enabling the oxygenation of protocatechuic acid and other catechols. 相似文献
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Regina Sibgatullina Katsumasa Fujiki Takefumi Murase Takahiro Yamamoto Taiji Shimoda Almira Kurbangalieva Katsunori Tanaka 《Tetrahedron letters》2017,58(20):1929-1933
One pot double click strategy containing strain-promoted click-reaction followed by 6π-azaelectrocyclization (RIKEN click reaction) has worked well in the synthesis of multivalent homogeneous and heterogeneous N-glycoalbumins. We have slightly changed the structure of linker unsaturated aldehyde used in this method. As a result it can be easily synthesized from commercially available material and furthermore, the enhancement of its reactivity towards both click-reactions was observed. The data described in this Communications facilitate the usage of the double click strategy as a general method for the synthesis of a variety of neo-N-glycoproteins. 相似文献
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Jiří Málek Takefumi Mitsuhashi Naoki Ohashi Yuki Taniguchi Hitoshi Kawaji Tooru Atake 《The Journal of chemical thermodynamics》2011,43(3):405-409
The heat capacity of polycrystalline germanium disulfide α-GeS2 has been measured by relaxation calorimetry, adiabatic calorimetry, DSC and heat flux calorimetry from T = (2 to 1240) K. Values of the molar heat capacity, standard molar entropy and standard molar enthalpy are 66.191 J · K?1 · mol?1, 87.935 J · K?1 · mol?1 and 12.642 kJ · mol?1. The temperature of fusion and its enthalpy change are 1116 K and 23 kJ · mol?1, respectively. The thermodynamic functions of α-GeS2 were calculated over the range (0 ? T/K ? 1250). 相似文献
90.
Yutaka Hitomi Kengo Arakawa Masahito Kodera 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(43):14697-14701
We have reported previously that an iron(III) complex supported by an anionic pentadentate monoamido ligand, dpaqH (dpaqH=2‐[bis(pyridin‐2‐ylmethyl)]amino‐N‐quinolin‐8‐yl‐acetamido), promotes selective C? H hydroxylation with H2O2 with high regioselectivity. Herein, we report on the preparation of FeIII–dpaq derivatives that have a series of substituent groups at the 5‐position of a quinoline moiety in the parent ligand dpaqH (dpaqR, R: OMe, H, Cl, and NO2), and examine them with respect to their catalytic activity in C? H hydroxylation with H2O2. As the substituent group becomes more electron‐withdrawing, both the selectivity and the turnover number increase, but the selectivity of epoxidation shows the opposite trend. 相似文献