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71.
Two new amino acid-type amphoteric surfactants — disodiumN-(2-fatty acyl amino) ethyliminodiacetate and disodiumN-(2-fatty acyl amino) ethyl-N,N-bis[3-(2-hydroxy) propylsulfonate] amine — were synthesized using tall oil fatty acids as the raw material. Suitable processing conditions for synthesizing the intermediates and final products were probed. In addition, the chemical structures of the intermediates and the final products were identified by infrared spectroscopy, hydrogen nuclear magnetic resonance spectroscopy, and elemental analysis.  相似文献   
72.
73.
In 2019, several aquarium-reared fish died at a sea life park in Japan. Necropsy revealed micronodules on the spleen in the dotted gizzard shad (Konosirus punctatus). Seven of 16 fish exhibited microscopic multifocal granulomas associated with acid-fast bacilli in the spleen, kidney, liver, alimentary tract, mesentery, gills, and/or heart. Bacterial cultures yielded isolates from the dotted gizzard shad and a Japanese sardine (Sardinops melanostictus). Microbiological and molecular biological examinations revealed the isolates as Mycobacterium pseudoshottsii. To our knowledge, this is the first isolation of M. pseudoshottsii from aquarium-reared fish.  相似文献   
74.
For making efficient use of waste wood ash emitted from wood biomass plant, the wood and wood ash-based hydroxyapatite (HAp) composite was produced and their flammability characterization was studied by thermogravimetric (DTA-TG) analysis, oxygen index (OI) measurement and cone calorimeter test. The results show that the exothermic and weight loss peaks in DTA-TG combustion profiles due to their significant thermal decomposition were weakened by the HAp agent impregnation. In addition, the OI value of HAp composites was increased by the HAp combining and the OI showed a correlation with the HAp contents. Also, the cone calorimeter study revealed that the heat release rates were decreased with increasing amount of HAp injection and accordingly their total heat release has an inverse relationship to the HAp contents. These results indicate that the treatment with wood ash-based HAp agents can enhance the flame retardancy of the treated woods.  相似文献   
75.
本文通过对9条分布均匀、相对较窄的不同疏透度(透光疏透度,下同)(0.13~0.33)的树木林带和不同疏透度(0.00~0.80)风障组合的野外风速观测,确定了树木林带和风障的最适疏透度分别为0.25和0.13。基于林带结构(疏透度)与风速降低的关系,确定了林带主带间距离的主要参数,即,林带结构系数(δ)和以主害风为代表的小气候参数(Lrp)。另外,通过对林带树木的野外调查,应用树木解析技术确定林带成林高(H0)。因此,树木林带的主带间距可以通过林带结构系数、希望降低风速的比例和树木生长模型来确定。本文以杨树林带为例,具体确定了杨树林带的主带间距。该研究结果不仅适于树木林带的设计,同时适于其它生物材料或人工风障的设计。图4表5参40。  相似文献   
76.
77.
Due to a processing error, first author's name is missing in the HTML version of this article abstract page. The correct authors are given below: Jun Mu, Tohru Uehara, Takeshi Furuno The online version of the original article can be found at  相似文献   
78.
The individual growth of tree diameter at breast height (dbh) is analyzed in an even-aged plantation of Cryptomeria japonica from stand age of 45 to 94 years, to examine how the growth of individual trees has been affected by the changes in spacing resulting from thinning operations. At any age, a significant proportion (0.37–0.46) of the variation in dbh growth during a 5–11-year period was explained by dbh at the beginning of the period, probably due to greater leaf mass of larger trees. Next, either one-sided or two-sided competition was added to the model, by calculating the basal area (BA) of neighboring trees around each tree within a given radius or BA for trees having larger dbh than the focal tree within the radius. After preliminary analyses, a radius of 8 m was selected as the critical range for tree competition. Although both types of competition explained a significant proportion (0.09–0.43) of growth variation, one-sided competition was not significant at ages greater than 54 years. Based on the model at 45 years of age, the initial deviation of growth rate for each tree from the predicted rate was calculated and added to the models as a third variable. This raised the coefficient of determination up to 0.50–0.74. These findings have practical significance for forest plantation management, particularly for controlling the growth of standing trees via thinning, to produce high-quality timber in the future.  相似文献   
79.
As a new use of bamboo, bamboo cubes may be useful as a shot-blast material for surface treatments. However, a suitable processing technique for bamboo cubes has not been established. In this study, to obtain basic knowledge regarding the processing technology for bamboo cubes, we installed shearing blades (upper and lower blades) in a universal testing machine to test cross-sectional shearing of bamboo. The shearing force generated in this shearing was composed of a vertical component (F v), a forward component (F f), and a side component (F s). This shearing force (F v, F f, and F s) and the machining accuracy were investigated under various processing conditions. The shearing force became larger as the thickness of bamboo increased. In particular, F v showed a tendency to increase rapidly. Changes in the shear angle of the upper blade had a remarkable influence on F v. This result suggests that the shearing force could be greatly decreased by adjusting the shear angle. The shearing force within bamboo of 3mm in thickness was almost unaffected by the blade angle, and the change of shearing force with increasing clearance was almost indiscernible. It was clearly demonstrated that a large number of bamboo cubes could be made when the shear angle was large and cross-sectional shearing was performed from the bark side. However, a consequence of a large shear angle is that burr area increases. Part of this article was presented at the 53rd Annual Meeting of the Japan Wood Research Society, Fukuoka, March 2003  相似文献   
80.
The spatial distribution patterns of the attack on fresh logs ofPasania edulis was studied for the oak borer,Platypus quercivorus (Murayama), and two species of Scolytid ambrosia beetles,Xylosandrus crassiusculus (Motschulsky) andXyleborus attenuatus Blanford, in 1994 and 1995. On the logs where onlyP. quercivorus attacked, the entry holes were distributed uniformly when attack intensity was low. However, the distribution pattern became more aggregated with the increase in attack intensity. On logs where bothP. quercivorus and the two Scolytid species attacked, there was a negative association between the spatial distribution of the entry holes ofP. quercivorus and that of scolytids. Simultaneous attack of two scolytids also increased the degree of aggregation of the entry holes ofP. quercivorus. The entry holes of scolytids were distributed in groups irrespective of the attack intensity of scolytids andP. quercivorus. These results suggest an asymmetrical interspecific relationship betweenP. quercivorus and scolytids. Concentration of the entry holes ofP. quercivorus in a small area may cause a considerable decline in the reproductive success in the galleries constructed there.  相似文献   
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