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51.
为研究CeO2添加对生物质催化气化制氢特性的影响,该研究采用分级气化系统分析了不同CeO2/Fe2O3比例(Ce∶Fe摩尔比为0∶1、3∶7、5∶5、7∶3、1∶0)双金属催化剂对纤维素水蒸气催化重整制氢气体产物产量、组成以及催化剂的结构演变特性的影响。结果表明,CeO2/Fe2O3催化剂在制氢反应中的催化性能明显优于纯CeO2或Fe2O3催化剂,当Ce∶Fe摩尔比为3∶7时,在800℃下氢气的最大产率为21.63 mmol/g(以纤维素计,下同);当温度大于等于800℃时,催化剂氧化还原反应后可生成CeFeO3,且CeFeO3的存在对纤维素水蒸气气化过程有促进作用。CeO2的引入提高了催化剂的氧化性能和稳定性,提高了使用寿命。该研究对生物质气化机制的深入理解具有一定的指导意义。 相似文献
52.
Yuji Sumii Kentaro Kamiya Takehiko Nakamura Kenta Tanaka Takumi Kaji Junya Mukomura Naoyuki Kotoku Masayoshi Arai 《Marine drugs》2022,20(2)
The current tuberculosis treatment regimen is long and complex, and its failure leads to relapse and emergence of drug resistance. One of the major reasons underlying the extended chemotherapeutic regimen is the ability of Mycobacterium tuberculosis to attain a dormant state. Therefore, the identification of new lead compounds with chemical structures different from those of conventional anti-tuberculosis drugs is essential. The compound 3-(phenethylamino)demethyl(oxy)aaptamine (PDOA, 1), isolated from marine sponge of Aaptos sp., is known as an anti-dormant mycobacterial substance, and has been reported to be effective against the drug resistant strains of M. tuberculosis. However, its target protein still remains unclear. This study aims to clarify the structure–activity relationship of 1 using 15 synthetic analogues, in order to prepare a probe molecule for detecting the target protein of 1. We succeeded in creating the compound 15 with a photoaffinity group that retained antimicrobial activity, which proved to be a suitable probe molecule for identifying the target protein of 1. 相似文献
53.
Yasuo Tomida Toshiya Suzuki Tsutomu Yamada Ryuji Asami Hirofumi Yaegashi Yasufumi Iryu Tsuguo Otake 《Fisheries Science》2014,80(2):273-280
We examined differences in otolith oxygen (δ18Ootolith) and carbon (δ13Cotolith) stable isotope ratios between hatchery and wild pink salmon fry. The δ18Ootolith values of hatchery and wild fry were ?7.7 ± 0.2 ‰ and ?8.3 ± 0.3 ‰ (1σ), respectively. This difference reflected differences in temperature conditions experienced by each fry. The δ13Cotolith values of hatchery and wild fry were ?19.2 ± 0.3 ‰ and ?11.1 ± 1.8 ‰ (1σ), respectively. The lower δ13Cotolith values of hatchery fry were probably related to their intake of artificial diets. Discriminant analysis of δ18Ootolith and δ13Cotolith values demonstrated a highly significant difference between hatchery and wild fry with 95.8 % classification accuracy. Therefore, analysis of δ18Ootolith and δ13Cotolith precipitated in the fry stage may be useful for discriminating the origin of returning adult pink salmon. The discrimination method for returning adult fish would provide important information for evaluating the effect of hatchery release and their impact on the wild population. 相似文献
54.
Toshie Wakabayashi Nobuaki Suzuki Mitsuo Sakai Taro Ichii Seinen Chow 《Fisheries Science》2006,72(3):494-502
ABSTRACT: A total of 110 adult individuals from four ommastrephid (family Ommastrephidae) squid species ( Ommastrephes bartramii, Sthenoteuthis oualaniensis, Eucleoteuthis luminosa, and Hyaloteuthis pelagica ) were used to obtain diagnostic DNA markers for species identification. Restriction fragment length polymorphism (RFLP) analysis of a partial segment (855 bp) of the mitochondrial DNA cytochrome oxidase I (COI) gene amplified by polymerase chain reaction (PCR) revealed that the restriction profiles of two endonucleases ( Alu I and Tsp 509 I) were diagnostic for species identification. The restriction assay partially supplemented with nucleotide sequence analysis successfully assigned 69 damaged and morphologically equivocal ommastrephid paralarvae collected in northern Hawaiian waters, identifying 60 O. bartramii , eight S. oualaniensis , and one E. luminosa . The family Ommastrephidae appears to be monophyletic. Although the phylogenetic relationships among genera were not resolved well due to apparent homoplasy and large genetic divergence between species, COI sequence data without transitions provided support for subfamily level relationships. 相似文献
55.
Kenji Nohara Hiroyuki Takeuchi Tatsuo Tsuzaki Nobuaki Suzuki Osamu Tominaga Tadahisa Seikai 《Fisheries Science》2010,76(1):75-81
Sequence analysis based on the anterior part of the mitochondrial DNA control region was carried out to reveal the genetic diversity, stock structure, and historical demography of the red tilefish. Nucleotide sequences of 388 bp in length were determined for 280 individuals taken from eight localities. The molecular diversity, haplotype diversity, and nucleotide diversity were relatively high (average h = 0.929 ± 0.011; average π = 0.008 ± 0.005). The mismatch distribution was not significantly different from the expected distribution for a rapidly expanding population (P = 0.453). The minimum spanning network connecting with full-sequence haplotypes contained star-like topologies derived from multiple ancient lineages, supporting the mismatch distribution analysis. No significant genetic differentiation was observed among eight localities (maximum pairwise F ST = 0.023, reduced-sequence data set). Our results suggest a large panmictic population of the red tilefish along the coast of Honshu to the East China Sea. 相似文献
56.
Suzuki J Miwa N Kumazaki K Abe M Kamanaka Y Matsubayashi N Gotoh S Matsubayashi K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(4):361-366
To clarify the influence of rearing conditions on the growth of various body parts of Japanese macaques (Macaca fuscata), two groups reared under different conditions, i.e., a group born and reared in open enclosures (Enclosure group) and another consisting of macaques born and reared in cages (Caged group), were somatometrically analyzed. Somatometric data on 36 measures of various body parts were collected from 77 males and 92 females. Growth in many body parts was smaller in the Caged group than in the Enclosure group. Body parts that exhibited large incremental increases were more sensitive to differences in rearing space at the infantile growth stage in both sexes. Recovery from delayed growth at the pubertal growth stage was found in many body parts. However, the size of some locomotor elements such as the wrist and hand, and ankle and foot strongly reflected limitations of space and changes due to this were irreversible. Females were more sensitive than males to such differences in rearing conditions. We conclude that open enclosures with ample rearing space are necessary for the innate growth of Japanese macaques to occur. 相似文献
57.
Yabuki A Maeda M Suzuki S Matsumoto M Kurohmaru M Hayashi Y Taniguchi K Nishinakagawa H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(4):461-465
Although mice kidney morphology shows various sexual dimorphisms, the effect of the estrous cycle has not previously been discussed. In this study, we investigated the effects of the estrous cycle on kidney morphology, including renin-positive areas, of female DBA/2 mice. No effects were confirmed in most of the histometrical parameters, however, the percentage of the renal corpuscles in which cuboidal epithelium covered under 50% of the parietal layer was significantly higher during estrus compared to that during anestrus. 相似文献
58.
59.
Shozo TOMONAGA Yuji KAJI Tetsuya TACHIBANA D. Michael DENBOW Mitsuhiro FURUSE 《Animal Science Journal》2005,76(3):249-254
Carnosine, and its derivative anserine, are known to function as anti‐oxidants and putative neurotransmitters. They are especially rich in the breast muscle (Musculus pectoralis superficialis, MPS) of chickens. To clarify whether the concentrations of carnosine and anserine are altered by dietary management, the effect of oral administration of their constituent, β‐alanine (β‐Ala), was determined in the MPS and brains of chickens. Birds were orally administered β‐Ala (22 mmol/kg) twice a day for five consecutive days (from 2 to 6 days old). In the MPS, carnosine was increased by β‐Ala, whereas anserine and taurine were decreased. The concentrations of other free amino acids in the MPS were also modified by β‐Ala. In the brain, the oral administration of β‐Ala increased anserine and carnosine and decreased taurine, but caused no changes to other free amino acid concentrations. These results suggest that orally administered β‐Ala increases carnosine concentrations in both the MPS and brains of chickens. However, the effects of β‐Ala on other concentrations differ depending on the tissues. 相似文献
60.
Sato H Miyazaki H Sakakura H Suzuki T Saito H Maehara N 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1999,46(2):73-84
The rapid growth and high survival rate of Erysipelothrix rhusiopathiae was determined using a culture of the bacterium in tryptic soy broth supplemented with 0.3% Tris-hydroxymethyl aminomethane and 0.1% Tween 80 (TT-TS broth). High concentrations of 64, 66 and 43 kDa proteins, which are associated with protection against E. rhusiopathiae infection in mice, were obtained by alkaline treatment of whole cells using 0.05-1 N NaOH. The supernatant of alkaline treated cells (alkaline extract; AE) was stable at alkaline or neutral pH. However, aggregates appeared at neutral pH in the absence of sodium dodecyl sulphate (SDS). A high yield of 64, 66 and 43 kDa proteins was obtained from strain Agata (serovar 5). The proteins were eluted from gel bands following SDS-polyacrylamide gel electrophoresis (SDS-PAGE) of the AE from strain Agata and designated P64 and P43. The amounts of P64 and P43 isolated were 0.7 and 0.3 mg/16 g of wet bacteria, respectively. In a mouse protection test, 50% protective doses (PD50) of P64 and P43 were 0.58 and 0.63 microgram, respectively. Upon Western blotting of the AE, both anti-P64 and anti-P43 antibodies reacted with the 64 and 43 kDa proteins. From these results, it is suggested that P64 is the most effective protective antigen and that P43 (43 kDa protein) is a degradation product of P64. Therefore, the 64 kDa structural proteins are associated with the induction of a protective activity against E. rhusiopathiae infection in mice. 相似文献