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81.
Hongyu Huang Noriyuki Kobayashi Miwa Sakata Yuko Suzuki Fujio Watanabe Masanobu Hasatani Kiyoshi Matsuyama Shigenori Yoshida Yoshihito Mitsuhara 《Journal of Material Cycles and Waste Management》2007,9(2):182-187
Polychlorinated biphenyl (PCB) residues from the sodium dispersion (SD) process were employed as the raw materials for the
production of activated carbon using KOH activation. The pore properties, such as the specific surface area and pore size
distribution, were characterized using the Barrett–Joyner–Halenda method and the Horvath–Kawazoe method based on the N2 adsorption isotherm at 77 K. The activated carbon produced showed similar adsorption capacities and specific surface areas
to the commercially available product. The effects of the activation conditions on the porosity of the activated carbon produced
were studied. The most significant factor affecting the specific surface proved to be the activation temperature. The activated
carbon produced from PCB residues from the high-temperature (423–443 K) SD process had a binary pore size distribution well
developed in the 4 nm region and in the micropore region. The pore structure of the carbon produced from PCB residues from
the low-temperature (333–393 K) SD process had a wide range of micropores and mesopores. 相似文献
82.
The conspicuous morphogenesis during termite soldier differentiation is one of the most remarkable examples of specialized caste development in social insects. To clarify the mechanism of morphological changes during soldier differentiation, mandibular morphogenesis prior to the presoldier moult was examined in the damp-wood termite Hodotermopsis sjoestedti. Using experimental induction of presoldier differentiation from pseudergates (7th or later instar larvae) by the application of juvenile hormone analogue (JHA), we compared mandibular morphogenesis in a presoldier moult (from pseudergate to presoldier) with that of a stationary moult (from pseudergate to pseudergate). Future presoldier mandibles were formed under the old mandibular cuticle of the pseudergates just prior to the presoldier moult. Multiple folds of both epidermis and new cuticle were observed in the developing mandible, and large concavities between teeth were formed on the mandibular surface. While in the stationary moult, the future mandibles were formed with a smooth surface. The process of the mandibular morphogenesis in soldier differentiation explains the allometry of soldier mandibles. The morphological differences in mouth parts between castes arise from a switching mechanism that triggers caste-specific mandibular epithelial growth during development. 相似文献
83.
It is generally recognized that the sonographic findings of infantile polycystic kidney disease (IPKD) are bilaterally enlarged kidneys, oligohydramnios, an absent fetal bladder, and the typical kidney texture. Since there is a broad spectrum of renal compromise with IPKD, in utero diagnosis is thought to be limited to the severe forms. This paper reports a mild case of IPKD, where the in utero diagnosis was established by measuring fetal urine production and amniotic fluid volume serially during pregnancy, and by ultrasonographic examination of fetal kidneys. 相似文献
84.
Dr. Naomichi Matsumoto Nakamichi Saito Naoki Harada Kiyoji Tanaka Norio Niikawa 《黑龙江环境通报》1995,15(7):675-677
DNA-based prenatal carrier detection of group A xeroderma pigmentosum (XP-A) is reported. Chorionic villus sampling was done at the tenth gestational week in a pregnant woman whose first child suffers from XP-A. Genomic DNAs from the villi, proband, and parents were PCR (polymerase chain reaction)-amplified using three sets of primers, because the PCR and a subsequent enzyme digestion with HphI, AlwNI, or MseI may detect the three most frequent mutations of the XP-A complementing gene (XPAC) in Japanese XP-A patients. The results showed that the proband is a homozygote and that the parents and fetus are heterozygotes for a base substitution at the 3′ acceptor site of intron 3 of XPAC, indicating that the fetus is a healthy carrier of XP-A. This is the first case of prenatal carrier detection of the disorder. 相似文献
85.
86.
Ayako Yoshino Yasuhiro Sadanaga Keisuke Watanabe Shungo Kato Yuko Miyakawa Jun Matsumoto Yoshizumi Kajii 《Atmospheric environment (Oxford, England : 1994)》2006,40(40):7869-7881
Total OH reactivity was observed by use of the laser-induced pump and probe technique, and the urban air quality in Tokyo was diagnosed comprehensively. The concentrations of NOx, CO, O3, non-methane hydrocarbons (NMHCs) and oxygenated volatile organic compounds (OVOCs) were observed simultaneously. The observations were conducted in July and August 2003, and in January, February, May, and November 2004. Generally, the observed OH reactivity was higher than the calculated values derived using the observed concentrations of the trace species. The differences between the observed and calculated values in summer, spring, and autumn were approximately 30%. However, the difference in winter was smaller than those in the other seasons. In addition, while the differences observed in summer, spring, and autumn correlated with the total reactivity of the OVOCs (Σi kOVOCi[OVOCi](s−1), ki is rate constant of its compounds with OH), the correlations were not confirmed in the case of winter because atmospheric oxidation was less active and OVOCs levels were low in winter. These results suggest that the secondary products of the photochemical reactions in the atmosphere would be a missing sink for the OH loss process in the urban area. 相似文献
87.
The conversion of arsenobetaine into other arsenic compounds by microorganisms occurring in the bottom sediments from coastal waters was demonstrated for the first time. Three arsenic metabolites were observed on high performance liquid chromatogram during incubation at 25 °C for 80 days in 2 kinds of media, 1/5 ZoBell 2216E and a medium composed of inorganic salts. The time course pattern of arsenic metabolites during incubation was fairly different between these 2 media. 相似文献
88.
Ammonia volatilization from livestock manure is one of the most important pathways of nitrogen loss from agricultural cultivated fields. In this paper, we report the measurement of ammonia emission from cattle slurry manure applied to upland in Miyazaki, Japan. It has been determined that after the cattle slurry was sprayed on the upland surface, the emission flux of the first day was 110 microg N ha(-1) s(-1). The loss of NH4(+) -N in the applied slurry was 60% after 5 days following the spraying of cattle slurry. 相似文献
89.
Most of the oxalotrophic bacteria are facultative methylotrophs and play important ecological roles in soil fertility and
cycling of elements. This study gives a detailed picture of the taxonomy and diversity of these bacteria and provides new
information about the taxonomical variability within the genus Methylobacterium. Twelve mesophilic, pink-pigmented, and facultatively methylotrophic oxalate-oxidizing strains were included in this work
that had been previously isolated from the soil and some plant tissues by the potassium oxalate enrichment method. The isolates
were characterized using biochemical tests, cellular lipid profiles, spectral characteristics of carotenoid pigments, G+C
content of the DNA, and 16S rDNA sequencing. The taxonomic similarities among the strains were analyzed using the simple matching
(S
SM) and Jaccard (S
J) coefficients, and the UPGMA clustering algorithm. The phylogenetic position of the strains was inferred by the neighbor-joining
method on the basis of the 16S rDNA sequences. All isolates were Gram-negative, facultatively methylotrophic, oxidase and
catalase positive, and required no growth factors. Based on the results of numerical taxonomy, the strains formed four closely
related clusters sharing ≥85% similarity. Analysis of the 16S rDNA sequences demonstrated that oxalotrophic, pink-pigmented,
and facultatively methylotrophic strains could be identified as members of the genus Methylobacterium. Except for M. variabile and M. aquaticum, all of the Methylobacterium type strains tested had the ability of oxalate utilization. Our results indicate that the capability of oxalate utilization
seems to be an uncommon trait and could be used as a valuable taxonomic criterion for differentiation of Methylobacterium species. 相似文献
90.
The evolution of genome size has been discussed in relation to the evolution of various biological traits. In the present study, the genome sizes of 22 dictyopteran species were estimated by Feulgen image analysis densitometry and 6-diamidino-2-phenylindole (DAPI)-based flow cytometry. The haploid genome sizes (C-values) of termites (Isoptera) ranged from 0.58 to 1.90 pg, and those of Cryptocercus wood roaches (Cryptocercidae) were 1.16 to 1.32 pg. Compared to known values of other cockroaches (Blattaria) and mantids (Mantodea), these values are low. A relatively small genome size appears to be a (syn)apomorphy of Isoptera + Cryptocercus, together with their sociality. In some phylogenetic groups, genome size evolution is thought to be influenced by selective pressure on a particular trait, such as cell size or rate of development. The present results raise the possibility that genome size is influenced by selective pressures on traits associated with the evolution of sociality. 相似文献