Synthesis of the protected tetrasaccharide II is reported as the key intermediate of tetrasaccharide from laminin that is an important glycoprotein on the basement membrane.
A comparative study on chloroplast ultrastructure and light harvesting complex of photosystem Ⅱ （LHC Ⅱ） was conducted between a new rice mutant （W2555） and its wild type （WT）. The chloroplasts of W2555 had les...A comparative study on chloroplast ultrastructure and light harvesting complex of photosystem Ⅱ （LHC Ⅱ） was conducted between a new rice mutant （W2555） and its wild type （WT）. The chloroplasts of W2555 had less thylakoids and grana stacks compared with the wild type. There was no significant change in the composition of LHC Ⅱ polypeptide in W2555, while a decline had been noted in LHC Ⅱ content. Northern blot analysis with a specific cab gene probe showed no appreciable difference in the LHC Ⅱ mRNA level between the W2555and its wild type. The precursors of chlorophyll synthesis, 6-aminolevulinic acid （ALA） and porphobilinogen （PBG） were over accumulated in W2555, but the other precursors were all decreased. These results indicated that the decreased level of LHC Ⅱ in the mutant W2555 was attributed to the change of cab gene transcription, but a blockage in chlorophyll biosynthesis due to the formation of uroporphyrinogen Ⅲ （Urogen Ⅲ）.展开更多
Nanocrystallite δ ′ ZrW 1.6 Mo 0.4 O 8 was prepared in the precursor route synthesis. The characterization by means of powder X ray diffraction (XRD) and selected area electron diffraction (SAED) showe...Nanocrystallite δ ′ ZrW 1.6 Mo 0.4 O 8 was prepared in the precursor route synthesis. The characterization by means of powder X ray diffraction (XRD) and selected area electron diffraction (SAED) showed it crystallized in a orthorhombic crystal system with a =0.896 9(7) nm, b =0.701 1(8) nm, c =0.596(1) nm. The possible space group is Pnnm (58) or Pnn2 (34). The compound crystallizes in a metastable phase during the synthesis process depending on temperature and crystallization time.展开更多
In this work,azobenzene mesogen-containing tin thiolates have been synthesized,which possess ordered lamellar structures persistent to higher temperature and serve as liquid crystalline precursors.Based on the preorga...In this work,azobenzene mesogen-containing tin thiolates have been synthesized,which possess ordered lamellar structures persistent to higher temperature and serve as liquid crystalline precursors.Based on the preorganized tin thiolate precursors,Sn S nanocrystals encapsulated with in-situ N-doped carbon layer have been achieved through a simple solventless pyrolysis process with the azobenzene mesogenic thiolate precursor served as Sn,S,N,and C sources simultaneously.Thus prepared nanocomposite materials as anode of lithium ion batteries present a large specific capacity of 604.6 m Ah·g^（-1）at a current density of 100 m A·g^（-1）,keeping a high capacity retention up to 96% after 80 cycles,and display high rate capability due to the synergistic effect of well-dispersed Sn S nanocrystals and N-doped carbon layer.Such encouraging results shed a light on the controlled preparation of advanced nanocomposites based on liquid crystalline metallomesogen precursors and may boost their novel intriguing applications.展开更多
The title compounds 6a—6f were prepared with high yield via intramolecular Wittig reaction of methyl 3-perfluoroalkyl-6-perfluoroacyl-2-triphenylphosphoranylidenehex-3,5-dienoates (5a—5i)which were obtained from the...The title compounds 6a—6f were prepared with high yield via intramolecular Wittig reaction of methyl 3-perfluoroalkyl-6-perfluoroacyl-2-triphenylphosphoranylidenehex-3,5-dienoates (5a—5i)which were obtained from the reaciton of 3-perfluoroacylprop-2-enylidenetriphenylphos- phoranes(3a—3c)with methyl perfluoroalkynoates(4a—4c).展开更多
文摘Synthesis of the protected tetrasaccharide II is reported as the key intermediate of tetrasaccharide from laminin that is an important glycoprotein on the basement membrane.
文摘A comparative study on chloroplast ultrastructure and light harvesting complex of photosystem Ⅱ （LHC Ⅱ） was conducted between a new rice mutant （W2555） and its wild type （WT）. The chloroplasts of W2555 had less thylakoids and grana stacks compared with the wild type. There was no significant change in the composition of LHC Ⅱ polypeptide in W2555, while a decline had been noted in LHC Ⅱ content. Northern blot analysis with a specific cab gene probe showed no appreciable difference in the LHC Ⅱ mRNA level between the W2555and its wild type. The precursors of chlorophyll synthesis, 6-aminolevulinic acid （ALA） and porphobilinogen （PBG） were over accumulated in W2555, but the other precursors were all decreased. These results indicated that the decreased level of LHC Ⅱ in the mutant W2555 was attributed to the change of cab gene transcription, but a blockage in chlorophyll biosynthesis due to the formation of uroporphyrinogen Ⅲ （Urogen Ⅲ）.
基金Supported by the National Natural Science Foundation of China(No. 2 98710 0 6 ) .
文摘Nanocrystallite δ ′ ZrW 1.6 Mo 0.4 O 8 was prepared in the precursor route synthesis. The characterization by means of powder X ray diffraction (XRD) and selected area electron diffraction (SAED) showed it crystallized in a orthorhombic crystal system with a =0.896 9(7) nm, b =0.701 1(8) nm, c =0.596(1) nm. The possible space group is Pnnm (58) or Pnn2 (34). The compound crystallizes in a metastable phase during the synthesis process depending on temperature and crystallization time.
基金Project supported by the National Natural Science Foundation of China(Grant No.21574062)the Huaian High-Technology Research Institute of Nanjing University,China(Grant No.2011Q1)
文摘In this work,azobenzene mesogen-containing tin thiolates have been synthesized,which possess ordered lamellar structures persistent to higher temperature and serve as liquid crystalline precursors.Based on the preorganized tin thiolate precursors,Sn S nanocrystals encapsulated with in-situ N-doped carbon layer have been achieved through a simple solventless pyrolysis process with the azobenzene mesogenic thiolate precursor served as Sn,S,N,and C sources simultaneously.Thus prepared nanocomposite materials as anode of lithium ion batteries present a large specific capacity of 604.6 m Ah·g^（-1）at a current density of 100 m A·g^（-1）,keeping a high capacity retention up to 96% after 80 cycles,and display high rate capability due to the synergistic effect of well-dispersed Sn S nanocrystals and N-doped carbon layer.Such encouraging results shed a light on the controlled preparation of advanced nanocomposites based on liquid crystalline metallomesogen precursors and may boost their novel intriguing applications.
基金Project supported by the National Natural Science Foundation of China
文摘The title compounds 6a—6f were prepared with high yield via intramolecular Wittig reaction of methyl 3-perfluoroalkyl-6-perfluoroacyl-2-triphenylphosphoranylidenehex-3,5-dienoates (5a—5i)which were obtained from the reaciton of 3-perfluoroacylprop-2-enylidenetriphenylphos- phoranes(3a—3c)with methyl perfluoroalkynoates(4a—4c).
