Mesoporous N-doped carbon supported palladium catalyst Pd@CN0.132 was able to efficiently catalyze unprotected indole to indoline under mild conditions.In the aqueous system,a selectivity of 100% and conversion of 96% was achieved under 313 K and atmospheric hydrogen gas. 相似文献
Li4Ti5O12 (LTO)/carbon nanotubes (CNTs) composite material is synthesized based on a solid-state method by sand-milling, spray-drying and calcining at 850 ℃ under N2 flow. The LTO/CNTs samples with 1 wt% and 3 wt% weight ratio of CNTs addition and the pristine LTO sample are prepared. The rate performance and the thermal stability of these samples are investigated based on LiMn2O4 (LMO)/LTO full-cell. The results show that theweight ratio of CNTs addition has distinct effect on LTO performances. The composite materials of LTO composited CNTs have better performance at high-rate due to the intercalation enhancement by conductive network of CNTs. At second, the overcharging temperature response of the cell's surface with 1 wt% CNTs addition is the lowest. The particle size distribution is measured and the most uniform particles are obtained with 1 wt% CNTs addition. This trend could explain that the mediumquantity of CNTs is optimal to improve the heat and mass transfer and prevent the problems of crystallite growing interference and aggregation during the calcination process. 相似文献
Functionalized polyfluorene receives more and more attention due to its wide applications. Here, the syntheses of three novel polyfluorene‐based methacrylate macromonomers exhibiting a vast flexibility for further applications are reported. Their emissions strongly depend on the end groups and thus the macromonomers provide blue, green, and red emissions simultaneously with the same excitation light of 365 nm. Their well‐defined copolymers with 2‐(dimethylamino) ethyl methacrylate via reversible addition‐fragmentation chain transfer polymerization are investigated in detail. These copolymers exhibit high quantum yields in solid film (up to 0.8), and self‐assemble into photoluminescent nanoparticles in aqueous solutions with pure blue, green, and red emissions. By simply mixing them, perfect white light emission with high quality is obtained. These aqueous nanoparticles solutions are ready for ink‐jet printing to produce exquisite bright and colorful fluorescent pictures.
Novel diacetylene macrocycles 1 and 2 bearing dibenzylphosphine oxide were synthesised via Eglinton acetylenic intramolecular coupling. The X-ray analysis of crystals of macrocycles 1 and 2 demonstrated that the better-aligned tubular supramolecular structure was formed in macrocycle 1 than in macrocycle 2, which provided the possibility of diacetylene topochemical polymerisation in solid state of macrocycle 1. UV–vis, Raman spectroscopy and X-ray analysis indicated that the crystals of macrocycle 1 could undergo topochemical diacetylene polymerisation only on their surface by light irradiation; differential scanning calorimetry, solid-state 13C NMR spectroscopy and solubility test demonstrated that the crystals of macrocycle 1 could undergo diacetylene topochemical polymerisation inside solid by heat. As expected, based on the topological analysis of crystal structure, the crystals of macrocycle 2 could not undergo diacetylene topochemical polymerisation either by light irradiation or heat. 相似文献
Journal of Solid State Electrochemistry - Na3V2(PO4)3/C composite nanofibers are prepared successfully through a coaxial electrospinning technique and subsequent calcination. The diameter of the... 相似文献
Under iron-deficient conditions, Chlamydomonas exhibits high affinity for iron absorption. Nevertheless, the response, transmission, and regulation of downstream gene expression in algae cells have not to be investigated. Considering that the MAPK pathway is essential for abiotic stress responses, we determined whether this pathway is involved in iron deficiency signal transduction in Chlamydomonas.
Results
Arabidopsis MAPK gene sequences were used as entry data to search for homologous genes in Chlamydomonas reinhardtii genome database to investigate the functions of mitogen-activated protein kinase (MAPK) gene family in C. reinhardtii under iron-free conditions. Results revealed 16 C. reinhardtii MAPK genes labeled CrMAPK2–CrMAPK17 with TXY conserved domains and low homology to MAPK in yeast, Arabidopsis, and humans. The expression levels of these genes were then analyzed through qRT-PCR and exposure to high salt (150 mM NaCl), low nitrogen, or iron-free conditions. The expression levels of these genes were also subjected to adverse stress conditions. The mRNA levels of CrMAPK2, CrMAPK3, CrMAPK4, CrMAPK5, CrMAPK6, CrMAPK8, CrMAPK9, and CrMAPK11 were remarkably upregulated under iron-deficient stress. The increase in CrMAPK3 expression was 43-fold greater than that in the control. An RNA interference vector was constructed and transformed into C. reinhardtii 2A38, an algal strain with an exogenous FOX1:ARS chimeric gene, to silence CrMAPK3. After this gene was silenced, the mRNA levels and ARS activities of FOX1:ARS chimeric gene and endogenous CrFOX1 were decreased. The mRNA levels of iron-responsive genes, such as CrNRAMP2, CrATX1, CrFTR1, and CrFEA1, were also remarkably reduced.
Conclusion
CrMAPK3 regulates the expression of iron-deficiency-responsive genes in C. reinhardtii.
Novel TiO2/BiVO4 microfiber heterojunctions were constructed using cotton as biomorphic templates. The as-synthesized samples were characterized by scanning electron microscope, X-ray diffraction, X-ray photoelectron spectroscopy, UV-Vis diffuse reflectance spectra and photocatalytic experiment. The morphology of the as-synthesized TiO2/BiVO4 composites was consisted of a large quantity of microfiber structures with diameter from 2.5 μm to 5 μm, and the surface of samples became more coarse and compact with the increase of weight ratio of TiO2. The TiO2/BiVO4 samples with proper content (10.00wt%) showed the highest pho-tocatalytic degradation activity for methylene blue (MB) degradation among all the samples under visible light, and 88.58%MB could be degraded within 150 min. The enhancement of photocatalytic activity was mainly attributed to the formation of n-n heterojunction at the contact interface of TiO2 and BiVO4, which not only narrowed the band gap of BiVO4 for extending the absorption range of visible light, but also promoted the transfer of charge carriers across interface. A possible photodegradation mechanism of MB in the presence of TiO2/BiVO4 microfibrous photocatalyst was proposed. 相似文献