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51.
Complete Dehydrogenation of N2H4BH3 over Noble‐Metal‐Free Ni0.5Fe0.5–CeOx/MIL‐101 with High Activity and 100% H2 Selectivity
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Si‐Jia Li Hong‐Li Wang Ba‐Ri Wulan Xin‐bo Zhang Jun‐Min Yan Qing Jiang 《Liver Transplantation》2018,8(21)
Efficient and selective dehydrogenation of hydrazine borane (HB), a novel hydrogen storage material with very high hydrogen content (HB, 15.4 wt%), is a key challenge for a fuel‐cell‐based hydrogen economy. However, even using the noble metal catalysts for HB decomposition, the activities are still far from satisfying, to say nothing of non‐noble‐metal‐containing catalysts. In response, as a proof‐of‐concept experiment, herein, noble‐metal‐free NiFe–CeOx nanoparticles are successfully immobilized on an MIL‐101 support without surfactant by a simple liquid impregnation method. Unexpectedly, the resultant Ni0.5Fe0.5–CeOx/MIL‐101 catalyst shows good performance, including 100% H2 selectivity, 100% conversion, and record catalytic activity (351.3 h?1) for hydrogen generation at mild temperature, which is even better than most of the noble metal heterogeneous catalysts and might be attributed to the good dispersion and uniform particle size of the Ni0.5Fe0.5–CeOx nanoparticles due to steric restrictions effect of the MIL‐101 support. Additionally, extending MIL‐101 to some other important kinds of metal–organic framework (MOF) structures, the resultant NiFe–CeOx/MOF catalysts all show good catalytic activity toward HB decomposition, showing the universality of the MOF supported NiFe–CeOx catalysts. 相似文献
52.
Food Competition Between Wild Orangutans in Large Fig Trees 总被引:1,自引:0,他引:1
Utami Sri Suci Wich Serge A. Sterck Elisabeth H. M. van Hooff Jan A. R. A. M. 《International journal of primatology》1997,18(6):909-927
Orangutans are usually solitary. However, occasionally aggregations are formed, especially in large fruiting fig trees. Individuals in these aggregations may experience scramble or contest competition for food. We investigated the type and strength of food competition in large figs among wild Sumatran orangutans. Adult males foraged more efficiently than adult females and subadult males did. The availability of ripe fruit is positively related to the number of orangutans visiting a fig tree and their foraging efficiency. The number of orangutans in a fig tree did not affect patch residence time and foraging behavior, though orangutans spent more time feeding when aggregation size increased in a fig tree. Dominance relationships could be measured in a number of dyads. Differences in dominance did not affect foraging behavior. The patch residence time of subordinate individuals was reduced on days that a dominant individual also visited the fig. In conclusion, orangutans seem to adjust aggregation size to the number of available ripe fruits in a fig tree in such a way that scramble competition was absent. Contest competition determined access to large fig trees. 相似文献
53.
Thirteen species in four genera of mites of the family Macrochelidae phoretic on dung beetles were collected in the eastern part of the Lesser Sunda Islands, Indonesia, providing the first record of the family for that area. Of these, two species, Macrocheles entetiensis Hartini and Takaku, sp. nov. and Macrocheles sumbaensis Hartini and Takaku, sp. nov., are new to science. The remaining 11 species are Glyptholaspis fimicola, Holostaspella bifoliata, Macrocheles baliensis, Macrocheles sp. aff. glaber, M. hallidayi, M. kraepelini, M. krantzi, M. limue, M. merdarius, M. oigru and Neopodocinum sinicum. 相似文献
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Information about meat-eating behavior by wild orangutans (Pongo pygmæus) is scant. The first article about such a case dates from 1981. Since 1989, seven incidents of adult female Sumatran orangutans eating slow lorises (Nycticebus coucang) have been witnessed. Three females from two study sites were involved. In three cases the females were seen catching the prey. There are too few cases to conclude whether this behavior is typically female. Am. J. Primatol. 43:159–165, 1997. © 1997 Wiley-Liss, Inc. 相似文献
57.
Butler NS Theodossis A Webb AI Nastovska R Ramarathinam SH Dunstone MA Rossjohn J Purcell AW Perlman S 《PLoS pathogens》2008,4(10):e1000186
High affinity antigen-specific T cells play a critical role during protective immune responses. Epitope enhancement can elicit more potent T cell responses and can subsequently lead to a stronger memory pool; however, the molecular basis of such enhancement is unclear. We used the consensus peptide-binding motif for the Major Histocompatibility Complex molecule H-2K(b) to design a heteroclitic version of the mouse hepatitis virus-specific subdominant S598 determinant. We demonstrate that a single amino acid substitution at a secondary anchor residue (Q to Y at position 3) increased the stability of the engineered determinant in complex with H-2K(b). The structural basis for this enhanced stability was associated with local alterations in the pMHC conformation as a result of the Q to Y substitution. Recombinant viruses encoding this engineered determinant primed CTL responses that also reacted to the wildtype epitope with significantly higher functional avidity, and protected against selection of virus mutated at a second CTL determinant and consequent disease progression in persistently infected mice. Collectively, our findings provide a basis for the enhanced immunogenicity of an engineered determinant that will serve as a template for guiding the development of heteroclitic T cell determinants with applications in prevention of CTL escape in chronic viral infections as well as in tumor immunity. 相似文献
58.
Fourteen mite species in three genera of the family Macrochelidae were collected from the body surface of dung beetles (Scarabaeidae) in Mt Merapi National Park, Jogyakarta, Indonesia. Of these, three species, Macrocheles turgoensis n. sp., M. pumilus n. sp. and Glyptholaspis merapiensis n. sp., were described as new to science. The remaining 11 species were Glyptholaspis fimicola (Sellnick, 1931), Neopodocinum spinirostris (Berlese, 1910), M. dispar (Berlese, 1910), M. entetiensis Hartini and Takaku, 2005, M. hallidayi Walter and Krantz, 1986, M. jabarensis Hartini and Takaku, 2003, M. merdarius (Berlese, 1889), M. muscaedomesticae (Scopoli, 1772), M. oigru Walter and Krantz, 1986, M. sukaramiensis Takaku, 2001 and M. sp. aff. glaber (Müller, 1860). 相似文献
59.
Batai (Falcataria moluccana) is a valuable tree species for forest plantations in Malaysia and Indonesia. Since 1993, a gall rust disease has caused
severe damage to all growth stages, from seedlings in the nursery to mature trees in the field. To identify the fungus causing
gall rust disease on F. moluccana in Malaysia and Indonesia, study of the mode of infection and changes in the anatomy of infected cells were carried out in
the anatomy laboratory. The disease in Malaysia and Indonesia is caused by Uromycladium tepperianum. The fungus produces three longitudinally ridged teliospores on each head, with spores measuring 13–20 μm wide and 17–28 μm
long. The fungus is microcyclic, completing its entire life cycle on F. moluccana. This study confirmed that the teliospores themselves cannot infect the host. Under favorable conditions, about 10 h after
inoculation, teliospores germinate to produce basidiospores that form penetration pegs about 6 h later, and it is this peg
which penetrates the host cells directly through the epidermis. Pycnia, recognized as small brown pustules, break through
the epidermis about 7 days after inoculation. 相似文献
60.
Adam F Allred Guang Wu Tuya Wulan Kael F Fischer Michael R Holbrook Robert B Tesh David Wang 《BMC bioinformatics》2010,11(1):384