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排序方式: 共有388条查询结果,搜索用时 15 毫秒
71.
Takaaki Itai Teruyuki Maruoka Minoru Kusakabe Kenji Uesugi Muneki Mitamura 《Soil Science and Plant Nutrition》2013,59(3):450-454
Abstract In this paper, we proposed a new approach for on-site colorimetric analysis of ferrous ions (Fe2+) and ammonium-nitrogen (NH4 +-N) using a soil color meter as an alternative method to conventional spectrophotometry. The soil color meter we used can express solution color numerically on the basis of L*a*b* color space. After coloring of water by the 1, 10 phenanthroline method and the Indophenol blue method, the color of solution was measured by the soil color meter. A linear relationship between Fe2+ and a* or b* values, and systematic change of NH4 +-N with L* value, enable us to make a calibration curve. The Fe2+ and NH4 +-N concentrations in groundwater samples (Fe2+: 0.3–1.3 mg L?1; NH4 +-N: 0.02–0.62 mg L?1) determined by the proposed method agreed well with those determined by conventional spectrophotometry with the difference being ± 0.05 mg L?1 and ± 0.02 mg L?1, respectively. Since a similar apparatus is widely used in the soil science field, this technique would facilitate field surveys. 相似文献
72.
Viscosity and molecular weight of particle size fractions obtained from an Andosol humic acid (HA) were determined. Viscosity was determined both in solutions with and without the addition of 0.1 M NaCl (Cs 0.1 and Cs 0, respectively) at pH 7.0. Polyelectrolytic character was observed in the particle size fractions based on the changes in the concentration dependence of reduced viscosity with NaCI concentrations. The use of a Cs 0.1 solution was suitable for the determination of the values of intrinsic viscosity ([η]) of the particle size fractions. The [η] value increased with increasing weight average molecular weight ( M w) determined by gel permeation chromatography (GPC), and ranged from 4.3 to 12.9 X 10-3 (L g-1) in the Cs 0 solution and from 3.5 to 6.6 × 10-3 (L g-1) in the Cs 0.1 solution. A linear relationship between [η] in the Cs 0.1 solution and M w on a logarithmic scale, which was similar to the MarkHouwink equation, was observed. The value of the constant a calculated from the relationship, which reflected the polymer morphology, was 0.75 in the Cs 0.1 solution, and it corresponded to a polymer with flexible chains. 相似文献
73.
Yaguang Zhou Masami Fushitani Keiichi Sato Masayuki Ozawa 《Journal of Wood Science》2000,46(6):423-430
This study examined the bending creep behavior of hot-pressed wood during cyclic moisture changes. Sugi (Cryptomerica japonica D. Don) specimens were pressed in the radial direction under six combinations of nominal compressive strain (33% and 50%) and press temperatures (140°C, 170°C, 200°C). Creep tests were conducted at 20°C with three cyclic relative humidity changes between 65% and 95% under 25% of short-breaking stress. The effect of moisture content (MC) change on elastic compliance and mechanosorptive (MS) compliance was investigated. The relation between MS compliance and thickness swelling was studied. The results indicated that total compliance increased over the history of cyclic moisture changes; and its behavior was closely related to the changes in MC and thickness swelling. The total compliance increased during adsorption and decreased during desorption. Elastic compliance increased linearly with MC and was dependent on press temperature and compression. With increasing MC change, MS compliance increased during adsorption and decreased during desorption. The first adsorption led to greater MS compliance than did the subsequent adsorption with the same amount of MC change. In general, the elastic parameterK
E and the MS parameterK
Mincreased with compression and decreased as the press temperature increased. The MS parameterK
M was apparently greater than the elastic parameterK
E. The MS parameterK
M increased with swelling coefficient KSW of the hot-pressed specimen during adsorption and decreased with an increasing shrinkage coefficientK
SH during desorption. 相似文献
74.
Yoshinobu Uemoto Masayuki Takeda Atushi Ogino Kazuhito Kurogi Shinichro Ogawa Masahiro Satoh Fuminori Terada 《Animal Science Journal》2020,91(1)
The objectives of this study were to estimate genetic parameters and to perform a genome‐wide association study (GWAS) for predicted methane‐related traits in Japanese Black steers. The methane production and yield traits were predicted using on‐farm measurable traits, such as dry matter intake and average daily gain. A total of 4,578 Japanese Black steers, which were progenies of 362 sires genotyped with imputed 551,995 single nucleotide polymorphisms (SNPs), had phenotypes of predicted methane‐related traits during the total fattening period (52 weeks). For the estimation of genetic parameters, the estimated heritabilities were moderate (ranged from 0.57 to 0.60). In addition, the estimated genetic correlations of methane production traits with most of carcass traits and feed‐efficiency traits were unfavorable, but those of methane yield traits were favorable or low. For the GWAS, no genome‐wide significant SNP was detected, but a total of four quantitative trait locus (QTL) regions that explained more than 5.0% of genetic variance were localized on the genome, and some candidate genes associated with growth and feed‐efficiency traits were located on the regions. Our results suggest that the predicted methane‐related traits are heritable and some QTL regions for the traits are localized on the genome in Japanese Black steers. 相似文献
75.
Shinji Sasaki Eiji Muraki Yoshinobu Inoue Ryouhei Suezawa Hideki Nikadori Yuuichi Yoshida Shouta Nariai Ryoya Hideshima Shiyunsuke Moriwaki Ryotaro Nakashima Katsuo Uchiyama Kanako Yoshinari Masayuki Takeda Takatoshi Kojima 《Animal Science Journal》2019,90(12):1503-1509
Single nucleotide polymorphism (SNP) arrays are widely used for genetic and genomic analyses in cattle breeding; thus, data derived from SNP arrays have accumulated on a large scale nationwide. Commercial SNP arrays contain a considerable number of unassigned SNPs on the chromosome/position on the genome; these SNPs are excluded in subsequent analyses. Notably, the position‐unassigned SNPs, or “buried SNPs” include some of the markers associated with genetic disease. In this study, we identified the position of buried SNPs using the Basic Local Alignment Search Tool against the surrounding sequences and characterized the relationship between SNPs and genetic diseases in Online Mendelian Inheritance in Animals based on the genomic position. We determined the position of 285 buried SNPs on the genome and surveyed the genotype and allele frequencies of these SNPs in 5,955 individual Japanese Black cattle. Eleven SNPs associated with genetic disease, which contained five buried SNPs, were found in the population with the risk allele frequency ranging from 0.00008396 to 0.46. These results indicate that buried SNPs in the bovine SNP array can be utilized to identify associations with genetic disorders from large scale accumulated SNP genotype data in Japanese Black cattle. 相似文献
76.
The cause of the low survival rate of sweet pepper plants after grafting was investigated and compared with findings of eggplant and tomato plants, and the promotive effect of ascorbic acid (AA) was determined. Sweet pepper plants formed less callus at the cut surfaces of the stem compared to eggplant and tomato plants. Foliar application with 100 mg L−1 AA promoted callus formation at the cut surfaces of the scion stems and improved the survival rate after grafting. We suggest that the low survival rate of grafted sweet pepper plants is caused by their low rate of callus formation, and that AA can be used to promote graft-take through the acceleration of callus formation at the cut surfaces of the stems. 相似文献
77.
Murakami Hiroaki Yoon Seokjin Kasai Akihide Minamoto Toshifumi Yamamoto Satoshi Sakata Masayuki K. Horiuchi Tomoya Sawada Hideki Kondoh Michio Yamashita Yoh Masuda Reiji 《Fisheries Science》2019,85(6):1109-1109
Fisheries Science - In the original publication the text in right column of page 330, the sequences of primers were incorrectly published as. 相似文献
78.
Fire resistance of thick wood-based boards 总被引:1,自引:0,他引:1
Thick wood-based boards are used as construction materials for walls and floors in Japan. In this study, fire resistance tests
(ISO 834-1) and cone calorimeter tests (ISO 5660-1) were conducted for thick plywood, particleboard, and medium density fiberboard
with sample thicknesses of about 28–30mm, and their suitabilities for quasi-fireproof or fire-preventive structures were evaluated.
In the ISO 834-1 fire resistance test, the heat-shielding performance (insulation criterion) for walls was evaluated and the
results showed that the larger the apparent density of a woodbased board, the higher its insulation performance. The insulation
performance of thick wood-based boards in the fire resistance test could be forecast from the results of the cone calorimeter
test, especially when the second peak of heat release rate appeared. In the cone calorimeter tests, the surface layer density
of the plywood, particleboard, and medium density fiberboard was the dominant parameter for the time to ignition and initial
heat release rate. These results indicate that thick wood-based board is a suitable fire-preventive construction material.
Part of this study was presented at the Annual Meeting of the Architectural Institute of Japan, Hokkaido, Japan, August 2004 相似文献
79.
Yosuke Iimura Madoka Yoshizumi Tomonori Sonoki Mikiko Uesugi Kenji Tatsumi Ken-ichi Horiuchi Shinya Kajita Yoshihiro Katayama 《Journal of Wood Science》2007,53(6):541-544
To assess the possible utility of a fungal gene for manganese-dependent peroxidase (MnP) produced by a transgenic plant in
phytoremediation, we transformed hybrid aspen with a chimeric gene for MnP. Our gene construct allowed expression of the gene
for MnP in plants and relatively high MnP activity was detected in the hydroponic medium in which roots of plants that expressed
the transgene had been cultured. Some of our transgenic plants were able to remove bisphenol A from the medium more efficiently
than wild-type plants. Our results demonstrate that, without any modification of the coding sequence, a chimeric gene for
fungal MnP can be expressed in a woody plant, with secretion of active MnP from roots into the rhizosphere. Our strategy suggests
new options using woody plants for phytoremediation. 相似文献
80.
Flonicamid (IKI220; N-cyanomethyl-4-trifluoromethylnicotinamide), a pyridinecarboxamide compound, is a novel systemic insecticide with selective activity against hemipterous pests, such as aphids and whiteflies, and thysanopterous pests. The purpose of this study is to clarify the biological properties of flonicamid against aphids. Flonicamid is very active against aphids, regardless of differences in species, stages and morphs. This compound inhibited the feeding behaviour of aphids within 0.5 h of treatment without noticeable poisoning symptoms such as convulsion, and this antifeeding activity was not recoverable until death. The nymphs born from adults exposed to flonicamid for 3 h showed high mortality. The effect of flonicamid on the feeding activity of an individual aphid was studied using electronic monitoring of insect feeding behaviour (EMIF). Although the treated aphid attached the head of its proboscis to the leaf surface, salivation and sap feeding were strongly inhibited. These results suggest that the main insecticidal mechanism of flonicamid is starvation based on the inhibition of stylet penetration to plant tissues. 相似文献