共查询到20条相似文献,搜索用时 78 毫秒
1.
2.
25%噻虫·吡蚜酮WP防治稻飞虱田间试验研究 总被引:1,自引:0,他引:1
为明确25%噻虫·吡蚜酮WP对水稻褐飞虱及灰飞虱的防治效果,进行了小区药剂试验。结果表明:25%噻虫·吡蚜酮WP对灰飞虱和褐飞虱控制作用较好,建议在低龄若虫高峰期用药,制剂用量以180~360 g/hm2为宜。 相似文献
3.
4.
5.
6.
7.
2013年对褐飞虱进行6种杀虫剂田间防治效果评价。结果表明:施药后5 d和10 d,22%氟啶虫胺腈SC、20%呋虫胺SG、25%噻虫嗪WG、50%吡蚜酮WG对褐飞虱的防效分别为77.9%~90.9%和77.0%~90.5%,20%异丙威EC、25%噻嗪酮WP的防效分别为40.1%~65.9%和20.6%~49.9%。22%氟啶虫胺腈SC、20%呋虫胺SG、25%噻虫嗪WG、50%吡蚜酮WG防效较好。建议在实践中,轮换使用噻虫嗪、吡蚜酮、呋虫胺、氟啶虫胺腈防治褐飞虱。 相似文献
8.
9.
几种新烟碱类杀虫剂对褐飞虱的防效及用药技术研究 总被引:4,自引:0,他引:4
田间试验表明.10%烯啶虫胺AS、25%噻虫嗪WG和10%氯噻啉WP等三种新烟碱类杀虫剂防治五代褐飞虱,10%烯啶虫胺AS表现出良好的速效性和持效性,药后3~21d对褐飞虱防效分别在83.3%~100%,25%噻虫嗪WG速效性较差但持效性理想.药后3~21d对褐飞虱防效分别在55.9%~90%,10%氯噻啉WP防效不佳。对褐飞虱的防治技术进行了探讨,提出了褐飞虱的防治应贯彻“治前控后”的策略,做好药剂的交替使用,延缓褐飞虱抗药性的产生。 相似文献
10.
为了研究呋虫胺的杀虫活性和应用技术,通过室内生测初步明确了呋虫胺对豆蚜、褐飞虱、二化螟和小菜蛾的生物活性,结果表明:呋虫胺对稻飞虱具有高活性,LC_(50)和LC_(90)分别为0.877 8 mg/L和3.900 6 mg/L:对豆蚜亦具有高活性,LC_(50)和LC_(90)分别为0.350 5 mg/L和3.077 1 mg/L:对二化螟具有活性,LC_(50)和LC_(90)分别为55.721 5 mg/L和882.306 1 mg/L,;对小菜蛾活性低,以100 mg/L剂量处理3 d后死亡率为14.29%。通过研究呋虫胺与高效氯氟氰菊酯对豆蚜联合作用,发现它们配比3:1、4:1、5:1时具有增效作用;呋虫胺与吡蚜酮以配比1:1.5、1:2、1:2.5混用时对褐飞虱有显著增效作用;呋虫胺与烯啶虫胺以配比1:1、3:1、4:1、5:1混用时对褐飞虱有显著增效作用。通过田间小区试验,验证了呋虫胺对稻飞虱的防效,结果表明有效成分60~120 g/hm^2药后3~20 d的防效为73.34%~98.39%。经综合分析与评价,对呋虫胺的应用给出3个建议:呋虫胺防治稻飞虱是可行的,在应用剂量方面还可以优化;呋虫胺具有内吸性,希望在种子处理方面加强研发;呋虫胺在二化螟的防治上最好使用混配技术。 相似文献
11.
12.
13.
14.
15.
16.
Saturated very long chain fatty acids (fatty acids with greater than 22 carbon atoms; VLCFA) accumulate in peroxisomal disorders,
but there is little information on their turnover in patients. To determine the suitability of using stable isotope-labeled
VLCFA in patients with these disorders, the metabolism of 22-methyl[23,23,23-2H3]tricosanoic (iso-lignoceric) acid was studied in rats in vivo and in human skin fibroblasts in culture. The deuterated iso-VLCFA was degraded to the corresponding 16- and 18-carbon iso-fatty acids by rats in vivo and by normal human skin fibroblasts in culture, but there was little or no degradation in peroxisome-deficient (Zellweger’s
syndrome) fibroblasts, indicating that its oxidation was peroxisomal. Neither the 14-, 20-, and 22-carbon iso-fatty acids nor the corresponding odd-chain metabolites could be detected. In the rat, the organ containing most of the iso-lignoceric acid, and its breakdown products, was the liver, whereas negligible amounts were detected in the brain, suggesting
that little of the fatty acid crossed the blood-brain barrier. Our data indicate that VLCFA labeled with deuterium at the
ω-position of the carbon chain are suitable derivatives for the in vivo investigation of patients with defects in peroxisomal β-oxidation because they are metabolized by the same pathways as the
corresponding n-VLCFA. Moreover, as iso-VLCFA and their β-oxidation products are readily separated from the corresponding n-fatty acids by normal chromatographic procedures, the turnover of VLCFA can be more precisely measured.
A preliminary report of part of this work (Reference 18) was presented at the 5th International Symposium on the Synthesis
and Applications of Isotopes and Isotopically Labelled Compounds, Strasbourg, France, June 20–24, 1994. 相似文献
17.
为掌握佛山市顺德新城区降水中污染物的情况,2015年7月至8月,文章作者分别在雨天进行了降水取样,对降水中的pH、电导率、常见阴离子(F-、Cl~-、NO_3~(2-)、SO_4~(2-))及部分重金属(铅和镉)进行监测分析。选择有相关数据的珠江三角洲和石家庄、厦门等地的降水中污染物的情况进行对比。结果表明,顺德新城区降水中的p H和部分阴离子浓度优于珠江三角洲平均值,酸雨类型属于硫酸和硝酸混合型;其水体洁净程度略差于石家庄;铅和镉的浓度也高于厦门,甚至部分超出了人体能直接接触的安全范围。 相似文献
18.
H. Toda Y. Mochizuki T. Kawanishi H. Kawashima 《Nutrient Cycling in Agroecosystems》2002,63(2-3):167-173
In a coastal agricultural area in the central part of Japan (Shizuoka), we found decreasing nitrate concentration with depth in a shallow groundwater, where the depth to water table varied between 0.6 and 1.2 m below ground surface. High nitrate concentrations (5–29 mg N L–1) were often observed in the upper layer (0–2 m) of the groundwater, but the concentration decreased to less than 1 mg N L–1 in the deeper layer. Ammonium was scarcely detected, and the concentration of dissolved oxygen was usually low (< 1 mgO2 L–1) in the groundwater. Nitrate in the groundwater often had very heavy nitrogen stable isotope ratios (>20{}). There was a negative relationship between nitrogen stable isotope ratio of nitrate and its concentration. When nitrate was injected into the groundwater with acetylene and bromide (a conservative tracer), nitrate concentration decreased to 20% of the initial level within 5 days, accompanied by the increase in nitrite and nitrous oxide concentration and a little change in bromide concentration. These results indicate that microbial denitrification plays a potential role in the decrease of nitrate in shallow groundwater at the study site. 相似文献
19.
我国硝酸工业生产技术新进展 总被引:1,自引:0,他引:1
系统叙述了我国硝酸工业2000-2007年生产现状及主要技术成果,尤其指出了国产"四合一"机组的成功投运,使我国硝酸国产化装置取得较大的进步,表现在吨酸的铂耗、氨耗和能耗等方面接近国外引进装置水平,同时介绍了国外双加压法硝酸生产技术的进展.我国已成为硝酸生产大国,仍需以先进的技术改造和发展我国硝酸工业,确保我国硝酸工业健康有序地发展,加快从硝酸生产大国向强国迈进的步伐. 相似文献
20.
高效液相色谱法分析化妆品中微量成分的研究进展 总被引:1,自引:0,他引:1
综述了高效液相色谱法在化妆品中防腐剂、防晒剂中紫外线吸收剂以及性激素的检测等几个方面的应用;同时,介绍了分析所用的色谱柱、流动相、使用的检测手段以及样品的提取方法;最后针对目前存在的问题,提出了高效液相色谱用于化妆品中微量成分分析的研究方向和发展前景。 相似文献