几种除草剂对马铃薯安全性及混用效果

[目的]寻找适于马铃薯田阔叶杂草防除的除草剂。[方法]茎叶喷雾,测定除草剂对马铃薯安全性及杂草防除效果。[结果]砜嘧磺隆、灭草松、2甲4氯钠、草除灵对马铃薯相对安全。2甲4氯钠756 g a.i./hm~2、灭草松864 g a.i./hm~2单独使用均不足以完全防除阔叶杂草,而2甲4氯钠与砜嘧磺隆或灭草松混配对马铃薯田阔叶杂草防效达95%以上,产量较空白对照提高近40%,较人工除草处理提高5%以上。[结论]激素类除草剂2甲4氯钠与灭草松或砜嘧磺隆在马铃薯田混用具有重要应用前景。     

砜嘧磺隆的除草活性及对马铃薯的安全性

[目的]为了探讨砜嘧磺隆在马铃薯田应用的可行性,采用室内生物测定和田间小区试验的方法,研究了茎叶喷施25％砜嘧磺隆WG对杂草的活性和马铃薯的安全性.[结果]砜嘧磺隆对苘麻的室内活性高于稗草,对马铃薯安全性较好;田间小区试验对反枝苋的防效在95％以上,对禾本科杂草马唐、狗尾草防效在85％以上,对铁苋菜和饭包草防效差,在供试剂量范围内,对马铃薯安全.[结论]砜嘧磺隆可以在马铃薯田应用防除阔叶杂草及部分禾本科杂草.     

11%砜嘧·精喹OD对烟草田杂草的防除效果及安全性评价

分析了11%砜嘧·精喹可分散油悬浮剂(OD)对烟草田杂草的防除效果及安全性评价。结果表明,11%砜嘧·精喹OD对烟草田马唐、牛筋草、辣子草等一年生杂草均有防效,对烟草安全。施药剂量为60、99、132、198 g/hm~2,药后45 d的总草株防效为64.97%~99.15%,鲜重防效为72.42%~99.67%。从用药的经济性和安全性考虑,推荐11%砜嘧·精喹OD有效成分用量为99~132 g/hm~2。     

34%砜嘧·噻吩磺隆WG对玉米田一年生杂草的除草活性及安全性

为了明确34%砜嘧·噻吩磺隆WG对玉米田一年生杂草的除草活性及对玉米的安全性,进行了2年田间药效试验。结果表明:34%砜嘧·噻吩磺隆WG对玉米田一年生杂草如马唐、稗草、小藜等均具有较好的防除效果,药后15 d、30 d的总草株防效分别为86.76%~100.00%、83.26%~99.34%,药后30 d的总草鲜重防效为84.82%~99.50%。玉米平均增产15.85%~29.02%。34%砜嘧·噻吩磺隆WG的防效和增产效果明显优于25%砜嘧磺隆WG和75%噻吩磺隆WG。其在玉米田最佳有效成分用量为30.6~51.0 g/hm2,在此用量下对玉米安全。     

25%砜嘧磺隆WG防除玉米田杂草效果

为明确25%砜嘧磺隆WG防除玉米田杂草效果及对玉米的安全性,进行了田间药效试验。结果表明:25%砜嘧磺隆WG 75～90 g/hm2能有效防除玉米田杂草,药后45 d,对马唐、马齿苋的株防效为95.6%～98.5%,鲜重防效为96.8%～98.6%;对玉米安全,玉米增产10.9%～12.3%。     

不同除草剂对辣椒田杂草防除效果

[目的]明确精异丙甲草胺、丙草胺、乙草胺、二甲戊灵、嗪草酮·乙草胺、砜嘧磺隆等除草剂对辣椒田杂草的防除效果。[方法]土壤处理剂采用土壤喷雾法,茎叶处理剂在杂草2～4叶期采用茎叶喷雾法进行田间药效试验。[结果]960 g/L精异丙甲草胺EC、30%丙草胺EC、900 g/L乙草胺EC、330 g/L二甲戊灵EC、68.6%嗪草酮·乙草胺EC、25%砜嘧磺隆WG施药后45 d对杂草群体总株防效为65.91%～89.49%,总鲜重防效为72.14%～93.07%。[结论]辣椒田杂草以禾本科杂草为主时,可选用精异丙甲草胺、乙草胺、二甲戊灵进行土壤封闭处理;禾本科和阔叶杂草相当时选用嗪草酮·乙草胺进行土壤封闭处理;杂草苗后可选用砜嘧磺隆进行茎叶处理。     

4%氯吡嘧磺隆·烟嘧磺隆可分散油悬浮剂对玉米田杂草的防除效果研究

[目的]为明确氯吡嘧磺隆、烟嘧磺隆联合作用效果和4%氯吡嘧磺隆·烟嘧磺隆OD对玉米田杂草的防治效果以及对玉米的安全性进行研究。[方法]采用茎叶喷雾法测定了2种除草剂室内联合作用试验,并对筛选的4%氯吡嘧磺隆·烟嘧磺隆OD进行了田间药效试验。[结果]氯吡嘧磺隆、烟嘧磺隆以1:1复配对玉米田一年生杂草的联合作用较好,4%氯吡嘧磺隆·烟嘧磺隆OD的推荐使用剂量为42~54g a.i./hm2,药后35d对杂草的总体防效可达到93.4%~97.2%。[结论]氯吡嘧磺隆、烟嘧磺隆复配互补性强,对反枝苋等杂草增效作用明显,4%氯吡嘧磺隆·烟嘧磺隆OD能够有效防除玉米田一年生杂草,并对玉米安全。     

单嘧磺隆和扑草净对谷子田杂草的防除效果

[目的]筛选对谷子田杂草防除效果好且安全性高的除草剂，明确其合理使用剂量，为杂草高效防除提供理论参考。[方法]选取10%单嘧磺隆WP和40%扑草净WP，于山东滨州东孟村、闫家村2地进行试验，采用随机区组方法，分别测定药后21、42 d对杂草的防效，对作物的安全性及对谷子产量的影响。[结果]40%扑草净WP 258 g a.i./hm²+10%单嘧磺隆WP 129 g a.i./hm²处理对谷子田杂草的防除效果较理想，药后21 d的株防效达80%以上，药后42 d鲜质量防效达75%以上。但扑草净对作物长势抑制较明显，从防效和作物安全性考虑，扑草净用量不宜过大。[结论]谷子田防除杂草推荐使用40%扑草净WP 258 g a.i./hm²+10%单嘧磺隆WP 129 g a.i./hm²混合喷雾。     

马铃薯地上垄体栽培模式中杂草化学防除技术

[目的]为配合马铃薯地上垄体栽培模式,采用化学除草方法防除田间杂草。[方法]分别选用4组药剂对苗前土壤封闭处理、苗后茎叶处理,以探讨不同处理对马铃薯田杂草的最佳防效。[结果]90%乙草胺乳油10 L/hm2+25%草酮乳油9 L/hm2+48%仲丁灵乳油28 L/hm2苗前土壤封闭处理对杂草防效最佳,达95.42%;48%苯达松水剂3.75 L/h m2+25%砜嘧磺隆水分散粒剂0.02 k g/h m2苗后茎叶处理对杂草防效最佳,达99.00%。[结论]试验地可以将这2个处理配合使用,以达到最佳的杂草防除效果。     

30％五氟·丙·吡嘧可分散油悬浮剂水稻田除草药效试验

随着近年水稻直播田面积不断增加,水稻直播田中杂草防除存在诸多问题,如一季稻多次用药才能有效防除杂草,杂草抗性逐年增加,除草剂用量及费用不断增多。为了缓解以上问题,开发了30%五氟·丙·吡嘧可分散油悬浮剂(OD),并进行了对水稻直播田中杂草防效的研究。试验表明,30%五氟·丙·吡嘧OD用药量为360～900 g a.i./hm~2时在水稻直播田苗后早期封闭施用对一年生单、双子叶杂草防除效果优异:封闭效果好,持效期长,药后25 d,株和鲜重防效均在90%以上;对水稻安全性好。从多方面考虑,推荐30%五氟·丙·吡嘧OD施用剂量为360～540 g a.i./hm~2,此制剂是水稻直播田杂草防除的有发展前景的产品。     

佛山市顺德新城区降水中污染物的监测和分析

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。     

Metabolism of trideuterated iso-lignoceric acid in rats in Vivo and in human fibroblasts in culture

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.     

高效液相色谱法分析化妆品中微量成分的研究进展

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。     

Denitrification in shallow groundwater in a coastal agricultural area in Japan

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.     

我国硝酸工业生产技术新进展

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.