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Development of Orthographic Awareness, Morphological Awareness and Rapid Automatized Naming of Elementary-level Students in China: A Longitudinal Analysis from Grades 1 to 4 被引量:2
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作者 xiu luo Rui KONG +4 位作者 Ling-fei LIU Jia WANG Huai-ting GU Fang HOU Ran-ran SONG 《Current Medical Science》 SCIE CAS 2018年第2期336-341,共6页
The longitudinal study sought to examine the dynamic development of cognitive skills for reading among elementary-level students in China's Mainland. Two groups of students in first (n=164, mean age=6.65 years at... The longitudinal study sought to examine the dynamic development of cognitive skills for reading among elementary-level students in China's Mainland. Two groups of students in first (n=164, mean age=6.65 years at first test) and second grade (n=202, mean age=7.73 years at first test) were followed on orthographic awareness, morphological awareness and rapid automatized naming (RAN) for two years. The children exhibited significant improvement in orthographic awareness, morphological awareness and RAN from grades 1 to 4. More importantly, to the orthographic and morphological awareness, while the children took a leap from grade 1 to 2 and grade 3 to 4, the progress developed at relatively slow rates from grade 2 to 3. In order to assure children's development of orthographic and morphological awareness, evidence-based orthographically and morphologically enhanced instruction is needed for Chinese children in the early elementary years, especially for those at the stage from grade 2 to 3. 展开更多
关键词 orthographic awareness morphological awareness rapid automatized naming elementary-level students China
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Seismic running safety of trains and a new type of seismic-isolation railway structure
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作者 xiu luo 《Transportation Safety and Environment》 EI 2021年第2期152-165,共14页
Until now,seismic-isolation structures have not yet been applied in the railway field.The reason is that though a seismic-isolation structure can reduce the inertial force to the structure,the energy absorption causes... Until now,seismic-isolation structures have not yet been applied in the railway field.The reason is that though a seismic-isolation structure can reduce the inertial force to the structure,the energy absorption causes big response displacement on the structure,which adversely effects the running safety of the trains supported by the structure.In this paper,a methodology for seismic running safety assessment is introduced,and a new type of seismic-isolation foundation is proposed,which can convert the seismic response displacement in the lateral direction of track to the longitudinal direction that has a less adverse effect on the running safety of the train.The isolation foundation is composed of FPS(Friction Pendulum System)slider,concave plate and guide ditch.Moreover,through model experiments and 3D numerical simulation,it is verified that the proposed foundation can keep both the effects of the seismic isolation and the running safety of the train during an earthquake. 展开更多
关键词 seismic running safety of trains spectral intensity seismic-isolation foundation response-direction conversion system
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Nonheme Iron-Catalyzed Enantioselective cis-Dihydroxylation of Aliphatic Acrylates as Mimics of Rieske Dioxygenases
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作者 Jie Chen xiu luo +5 位作者 Ying Sun Si Si Yuankai Xu Yong-Min Lee Wonwoo Nam Bin Wang 《CCS Chemistry》 CAS 2022年第7期2369-2381,共13页
Enantioselective cis-dihydroxylation of alkenes represents an ideal route to synthesize enantioenriched syn-2,3-dihydroxy esters that are important structural motifs in numerous biologically and pharmaceutically relev... Enantioselective cis-dihydroxylation of alkenes represents an ideal route to synthesize enantioenriched syn-2,3-dihydroxy esters that are important structural motifs in numerous biologically and pharmaceutically relevant molecules.Bioinspired nonheme iron-catalyzed enantioselective cis-dihydroxylation meets the requirement of the modern synthetic chemistry from the atomic economy,green chemistry,and sustainable development perspectives.However,nonheme iron-catalyzed enantioselective cis-dihydroxylation is much underdeveloped because of the formidable challenges of controlling chemo-and enantioselectivities and product selectivity caused by the competitive epoxidation,cis-dihydroxylation,and overoxidation reactions.Herein,we disclose the fabrication of a biologically inspired nonheme iron complex-catalyzed enantioselective cis-dihydroxylation of multisubstituted acrylates using hydrogen peroxide(H_(2)O_(2))as the terminal oxidant by controlling the non-ligating or weakly ligating counterions of iron(Ⅱ)complexes,demonstrating a dramatic counteranion effect on the enantioselective cisdihydroxylation of olefins by H_(2)O_(2) catalyzed by nonheme iron complexes.A range of structurally disparate alkenes were transformed to the corresponding syn-2,3-dihydroxy esters in practically useful yields with exquisite chemo-and enantioselectivities(up to 99% ee).Given the mild and benign nature of this biologically inspired oxidation system as well as the ubiquity and synthetic utility of enantioenriched syn-2,3-dihydroxy esters as pharmaceuticals candidates and natural products,we expect that this strategy could serve as a promising complement to the well-known Sharpless asymmetric dihydroxylation,which is the chemical reaction of an alkene with OsO_(4) to produce a vicinal diol. 展开更多
关键词 bioinspired catalysis Rieske dioxygenase cis-dihydroxylation nonheme iron catalyst tetradentate nitrogen-donor ligand
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