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61.
28℃下利用三角瓶熏蒸法测试了甲酸乙酯和乙酸乙酯分别与辣根素原油以1∶9、2∶8、3∶7、4∶6、5∶5、6∶4、7∶3、8∶2、9∶1体积比的配方对赤拟谷盗成虫的联合毒力作用。结果显示,在大多数配比中,甲酸乙酯和乙酸乙酯均对辣根素原油均具有不同的显著增效作用。最佳配比均为6∶4,共毒系数分别为165.63和176.86。在两种药剂与辣根素混配比例为8∶2和9∶1时,均表现出拮抗作用,其中辣根素与甲酸乙酯的混配共毒系数分别为62.56、57.47,辣根素与乙酸乙酯混配的共毒系数分别为40.32、43.06。  相似文献   
62.
海绵状纤维素制品的研究进展   总被引:2,自引:0,他引:2  
海绵状纤维素制品指的是以纤维素为基本原料,通过一定方法,制备成一种类似聚氨酯海绵的产品。本文就目前世界上制备海绵状纤维素制品的方法及工业进展作了简要的综述,其中对醋酸纤维素水解法、黄原酸纤维素酯水解法、N-甲基氧化吗啉法进行了较详细的介绍,并指出了各种方法的特点。  相似文献   
63.
Beetle samples were compared between catches by traps and those on flowers in a Japanese beech (Fagus crenata Blume) forest, in Minakami, Gunma Prefecture, Japan. White plastic traps (Sankei Chemical Co., Ltd.) equipped with benzyl acetate were set out for a month from July 23 to August 23, 1993, and all beetles captured were collected every six days. During six days from August 10 to August 16, beetles were captured with traps and on wild flowers (Aruncus sylvester Kostel andAngelica polyclada Franch) at three hour intervals. Over the month, the traps captured 1,677 individuals of 73 species of 20 families, which included 16 (89%) species captured on flowers in the six-day period. Over the six days, the traps captured 327 individuals of 21 species of 12 families, compared with 685 individuals of 18 species of 5 families on the flowers; all of the families and nine (50%) species of beetles taken on the flowers were also captured by the traps; all of the species with more than five individuals captured on the flowers were also trapped. This suggests that capture by traps might sufficiently cover the beetle fauna on flowers. The number of species and individuals, as well as their changing patterns, however, varied more irregularly during the six-day period with the traps than with those on the flowers. A part of this paper were presented at the 46th meeting of the Kanto Branch of the Japanese Forestry Society (1994) These English titles are tentative translation by the authors from the originals  相似文献   
64.
New biodegradable cellulose acetate/layered silicate grafted poly(ε-caprolactone) [(CA/layered silicate)-g-PCL] nanocomposites were prepared by in situ polymerization of ε-caprolactone in the presence of cellulose acetate (CA) and organically modified layered silicate (OMLS). The structures of the resulting composites were investigated. X-ray diffractometry was carried out to survey general structural features of (CA/OMLS)-g-PCL nanocomposites, and revealed that OMLSs having hydroxyl groups in the organic modifiers greatly altered the layered silicate structure by monomer intercalation and successive exfoliation through its polymerization. Two of the representative cases were characterized by wide-angle and small-angle X-ray scattering analyses with a synchrotron source. The morphology of these nanocomposites was further examined by transmission electron microscopy. When SPN, one of OMLSs having one hydroxyl group in its modifier, was used, the silicate layers could not be dispersed thoroughly, but existed as aggregates consisting of several silicate layers. Among them, the crystal growth of PCL developed by transcrystallization, where the crystal growth was restricted in the confined space. When Cloisite 30B, having two hydroxyl groups within the modifier, was used, the silicate layers forming the clay were dispersed completely in the composite and random orientation of the OMLS was observed.  相似文献   
65.
赵淑英  王立安 《安徽农业科学》2012,40(35):17019-17021
[目的]利用醋酸纤维素薄膜电泳分析金针菇酯酶同工酶。[方法]以6种金针菇为材料,采用醋酸纤维素薄膜电泳对其酯酶同工酶进行分析,并与利用PAGE法得到的针菇酯酶同工酶图谱进行对比。[结果]6种金针菇共电泳得到20条酯酶同工酶带,其中相对迁移率不同的共有8条,大小分别为0.580、0.613、0.645、0.709、0.806、0.839、0.871、0.934;6种金针菇中,①号和②号有3条相同的带,④号和⑤号条带完全相同,③号与④号、⑤号有2条相同的带,⑥号与其他5种菌株间相同的条带较少。[结论]该试验结果与PAGE法显示的金针菇酯酶同工酶图谱基本一致,为实现利用醋酸纤维素薄膜电泳技术快速检测各类食用菌酯酶同工酶提供了可能。  相似文献   
66.
67.
对采用乙烯-醋酸乙烯酯共聚树脂和玻璃纤维纱线制作热熔胶线进行了分析研究,通过正交试验确定了乙烯-醋酸乙烯酯共聚树脂制作热熔胶线的最佳方案.  相似文献   
68.
对牡丹皮乙醇提取物及各萃取相进行了糖尿病小鼠实验,检测其对血糖及SOD、MDA的影响。结果表明,水相的降糖效果最好,乙酸乙酯相的抗氧化能力最强。综合降糖与抗氧化能力,乙酸乙酯相的抗糖尿病活性最强。  相似文献   
69.
The purpose of this study was to investigate the influence of soil geochemistry on the concentrations of Ca, K, Mg, P, Co, Ni, Zn, Mn, Cu, and Fe in cabbage (Brassica oleracea L. var. capitata) grown on acid sulfate (AS) soils in Western Finland. A total of 11 topsoil (0–20 cm) and corresponding cabbage samples and three whole‐soil profiles (≈ 0–260 cm) were collected on three agricultural fields. The concentrations of Co and Zn in cabbage were correlated with the NH4Ac‐extractable (easily available) concentrations in the topsoil, indicating that the uptake of these elements in cabbage is largely governed by soil geochemistry. Yet, the concentrations of Co and Zn in cabbage were not in general elevated relative to that of Finnish average values, although some AS soils showed enriched concentrations of these metals in the soil and cabbage. Significant geochemical differences (e.g., oxidation depth, organic‐matter and S content, pH) were observed among the studied AS soils, while, on the other hand, the concentrations of Ca, K, Mg, P, Ni, Mn, Cu, and Fe in cabbage were relatively similar. The hydroxylamine‐extractable concentrations of these elements in the topsoil were not correlated to those in cabbage, suggesting that uptake is not governed by the oxide‐bound fraction of these elements in the soil. Similarly, the easily available concentrations of Ca, P, Ni, Mn, Cu, and Fe in the topsoil were not correlated to those in cabbage, indicating that uptake is independent of the easily available concentrations in the soil. Hence, it is suggested that cabbage can regulate and thus optimize its concentrations of Ca, P, Ni, Mn, Cu, and Fe. Oxidation depth affected neither the easily available concentrations of Co, Ni, Zn, and Mn in the topsoil nor the concentrations in cabbage. However, the subsoil with a lower oxidation depth, which is to a smaller extent affected by leaching, may partly be enriched in these metals. Nevertheless, these showed no increased concentrations in cabbage. Based on these findings, it is suggested that the large amounts of metals mobilized in AS soils are easily lost to drains, subsequently contaminating nearby waterways and estuaries whereas they are only partly enriched in cabbage and other previously studied crops (oat).  相似文献   
70.
This study compared the sensitivity of acetate tape impression and skin squeezing with that of deep skin scraping for the diagnosis of demodicosis in dogs. Demodex canis was detected in 100% of acetate tape impressions obtained after skin squeezing and in 90% of deep skin scrapings. There was a significant difference (P < 0.001) between the techniques in the total number of mites detected. Acetate tape impression with skin squeezing was found to be more sensitive than deep skin scraping and is an alternative diagnostic method for canine demodicosis.  相似文献   
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