反相高效液相色谱法测定土壤中的(口恶)唑菌酮及其残留

建立了利用Novapak苯基柱,乙腈-0.01 mol/L的磷酸二氢钾(体积比45∶55,pH=3)为流动相,测定土壤中易保有效成分(口恶)唑菌酮残留量的反相高效液相色谱分析方法.进行了其最终残留和残留动态分析,其半衰期为9.5 d,为易消解农药(t1/2＜30 d).     

(口恶)唑菌酮在葡萄和土壤中的残留及消解动态

[目的]为研究(口恶)唑菌酮在葡萄园施用后在葡萄和土壤环境中的消解情况,建立了葡萄和土壤中(口恶)唑菌酮的残留检测方法并进行降解动态研究.[方法]样品以乙腈作为提取剂,经N-丙基乙二胺(PSA)净化,外标法定量,采用超高效液相色谱串联质谱检测.通过持续2年在2地葡萄园施用后进行降解动态检测,研究其在葡萄和土壤环境中的降...     

(口恶)唑菌酮(famoxadome)的环境行为及生物代谢研究进展

本文介绍了(口恶)唑菌酮(famoxadone)的环境行为以及在生物体内的代谢降解、残留分布及其生物毒性的研究进展。     

6-氯苯并(口恶)唑酮的合成

以邻氨基苯酚和尿素为原料生成苯并噁唑酮,再用过氧化氢 盐酸氯化制得6-氯苯并唑酮。通过TLC、IR和1HNMR对产物进行了表征。     

苄氧基苄基(口恶)唑酮类手性诱导试剂的合成研究

以N-Boc-L-酪氨酸乙酯为原料,经过酚羟基保护、酯基还原、氨基脱保护得到氨基醇,利用N,N-二甲基甲酰胺乙缩醛制备(口恶)唑啉环,在氨基锂作用下,与硒(硫)作用分别得到(4S)-4-(4'-苄氧基)苄基-(口恶)唑-2-硒酮和(4S)-4-(4'-苄氧基)苄基-(口恶)唑-2-硫酮手性助剂,总产率分别为39.2%和...     

啶菌(口恶)唑对大鼠致畸毒性

研究了啶菌(口恶)唑对大鼠的胚胎毒性和致畸作用.按照中华人民共和国国家标准GB/T 15670-1995(农药登记毒理学试验方法>应用Sprague Dawley大鼠进行致畸毒性实验,设20、100、500 mg/kg三个剂量组、阴性对照组和2 mg/kg敌枯双阳性对照组,给药时间为大鼠妊娠后第6天至第15天.实验结果表明:以500 mg/kg剂量经口投与Sprague Dawley妊娠大鼠,受孕大鼠的体重增长缓慢,但对胎鼠无影响.实验结论为啶菌(口恶)唑对胎鼠无胚胎毒性与致畸作用.     

52.5%(口恶)唑菌酮·霜脲氰水分散粒剂防治黄瓜霜霉病试验

通过对52.5%(口恶)唑菌酮·霜脲氰水分散粒剂和几种常用杀菌剂不同浓度稀释液喷雾防治温室黄瓜霜霉病田间药效试验,初步验证该药剂具有预防长久、治疗快速的特点,对黄瓜生长安全,在黄瓜生产中具有良好的应用前景.     

25%啶菌(口恶)唑乳油防治番茄灰霉病田间试验

2003—2005年多点的田间小区试验结果表明：25％啶菌噁唑乳油200—400μg／ml处理浓度,在发病初期喷施2—4次,间隔期6—8d,对番茄灰霉病的防治效果在85％以上,防效优于目前生产上推广使用的腐霉利、施佳乐、硫菌霉威等常规杀菌剂;25％啶菌嚼唑乳油与保护性杀菌剂福美双、百菌清混用,对番茄灰霉病同样具有优异防效。     

土壤中戊菌唑残留的分析方法

[目的]针对土壤中杀菌剂戊菌唑残留的检测,建立具有经济、环保等特点的快速可靠的分析方法。[方法]建立2种分析方法:柱色谱-超高效液相色谱法(CC-UPLC)和浊点萃取-超高效液相色谱法(CPE-UPLC)。[结果]经CC-UPLC和CPE-UPLC法处理,土壤样品戊菌唑的平均添加回收率分别为89.7%~102.4%、90.6%~94.8%;相对标准偏差分别为1.7%~6.1%、1.7%~3.0%;最低检出限分别为2.0、0.8滋g/kg。[结论]2种方法均能满足农药残留检测的要求,与CC-UPLC法相比,CPE-UPLC具有更好的准确度及灵敏度,符合绿色化学的发展趋势,是一种值得推荐的检测方法。     

氰氟草酯·精(口恶)唑禾草灵混剂在水体中的残留分析方法

建立了同时检测水体中氰氟草酯·精(口恶)唑禾草灵混剂的残留分析方法.结果表明,流动相为甲醇-水(体积比为75∶25),流速0.6 mL/min,检测波长233 nm,柱温30℃,进样量为20 μL;氰氟草酯和精(口恶)唑禾草灵的质量浓度分别在0.095～9.52 mg/L和0.114～11.44 mg/L范围内时,其质量浓度和峰面积的线性关系良好;样品添加质量浓度在0.01～0.50 mg/L范围内,平均添加回收率分别为88.82%～93.04%和96.10%～97.06%.该方法简便,准确度、精密度好,可满足水体中氰氟草酯和精(口恶)唑禾草灵残留量同时分析检测的需要.     

柑桔生产中杀菌剂(噁)唑菌酮残留量的控制

通过田间试验研究了,柑桔生产中杀菌剂噁唑菌酮的控制方法。结果表明：按推荐剂量即6．25％噁唑菌酮WG稀释1000倍液喷施桔树,最多4次,最后1次施药20d后采收,在收获的柑桔中噁唑菌酮的残留量低于最大残留限量,能够满足食品安全的要求。     

Phosphorus and potassium soil test and nitrogen leaf analysis as a base for citrus fertilization

A network of six NPK long-term field trials was carried out on different soils of citrus-producing regions of São Paulo state, Brazil, in order to estimate quantitative relations of fruit yield to NPK fertilization and to determine parameters for fertilizer recommendation based on soil testing and leaf analysis. The experiments were set up in an incomplete factorial design 1/2 4³ with 32 treatments, with four yearly rates of N (30, 100, 170 and 240 kg N/ha), P (9, 27, 45 and 63 kg P/ha) and K (25, 91, 157 and 223 kg K/ha). Four to seven harvests were recorded for the six experiments. Response surfaces of the type y = bo + b₁N + b₁₁N² + b₂P + b₂₂P² + b₃K + b₃₃K² + b₁₂NP + b₁₃NK + b₂₃PK were adjusted to the average yields of each trial. Correlation were established for yield increases, expressed as relative yields, and results of soil analysis of P and K, and leaf analysis of N. Soil samples taken at 0-20 cm depth in the beginning of each experiment were analyzed for resin extractable P and exchangeable K using an ion-exchange resin procedure. Yield responses for phosphorus and potassium applications were observed respectively in soils with less than 20 mg dm^-3 of P and 20 mmol_c dm^-3 of K⁺. Yield responses to nitrogen were related to the total content of nitrogen in leaves, being largest for N values of 23 g kg^-1 and smallest for N of 28 kg^-1. With these field information, a practical approach for fertilizer recommendation for citrus, based on soil analysis for P and K and leaf analysis for N, was developed.     

土壤条件和施肥对柑橘品质的影响

近年来,我国柑橘生产发展迅猛,产量连年增长,但品质不佳。为此,探讨了土壤条件和施肥对柑橘品质的影响,以期为优质柑橘的生产提供依据。     

马铃薯及土壤中三苯基羟基锡的残留分析

建立了杀菌剂三苯基羟基锡在马铃薯和土壤中的残留测定方法。样品以丙酮提取,石油醚萃取,中性氧化铝柱净化,液相色谱法测定。仪器最小检出量为2×10-10g;土壤、马铃薯叶和马铃薯中三苯基羟基锡残留的最低检出浓度分别为0.005、0.01、0.005mg/kg,土壤、马铃薯叶和马铃薯回收率分别为84.1%￣94.5%、85.6%￣95.6%、82.5%￣92.6%,其变异系数分别为0.78%￣1.84%、0.90%￣1.24%、0.53%￣1.15%。     

农药残留检测新方法研究进展

介绍了农药残留检测的步骤与方法.农药残留检测主要分为4个步骤:样品的提取、净化、浓缩和检测.提取方法主要有震荡法、索式提取法,固相微萃取法、超临界流体萃取法、快速溶剂萃取法等.净化方法主要有:液-液分配净化法、柱层析法、磺化法等.浓缩方法主要有:蒸发浓缩、反渗透浓缩、K-D浓缩仪浓缩等.检测方法主要有:气相色谱-质谱联用法、荧光分析法、酶抑制法、免疫分析法、生物传感器检测法、红外光谱法、拉曼光谱法等.评述了这些方法的优点与缺陷,提出了今后的发展方向.     

Available N in the root area for citrus orchards fertilized with sulphur-coated-urea and ammonium nitro-sulphate

The leaching of N fertilizers in citrus causes important N losses, thus exerting a direct influence on the economy of citrus production, and may have negative consequences on the environment. The use of controlled-release N fertilizers may reduce leaching and be a solution to this problem.The amounts of available N, expressed as g of N in a soil cylinder corresponding to the drip area of the tree and of 0–60 cm depth, were compared at different vegetative periods, in an orange orchard, for four treatments; two doses of a standard fertilizer (ammonium nitrate sulphate, ANS), applied in the quantities of 11.55 kg N/ha (ANS-350) and 49.50 kg N/ha (ANS-2×750) and two doses of a slow-release fertilizer (sulphur-coated urea, SCU), applied in the quantities of 11.55 kg N/ha (SCU-350) and 24.25 kg N/ha (SCU-750), in nine consecutive years. A treatment without N (no N) was included. Available total N throughout the whole of the vegetative cycle, and in partial critical periods, has been determined as another comparison term. In the same way, non-available N has been measured at the beginning and at the end of the experiment.SCU treatment applied in low doses and only in spring maintained high levels of available N in soil during the vegetative cycle, reducing N losses, compared with ANS treatments. In the whole annual cycle, the amounts of N with SCU-750 were 32% greater than those of ANS-(2×750) though the quantity of N applied with this treatment was double. SCU-350 provided 5% less N than ANS-(2×750), though the dose of N applied with this treatment was 4.3 times greater. In all critical periods, SCU-750 maintained quantities of N higher than those with ANS-(2×750). For SCU-350, the amounts of N were similar to those of ANS-(2×750), except in summer as a consequence of the second fertilization with ANS-(2×750). Non-available N increased during the experiment in all treatments providing N except in ANS-350. A good crop and quality of fruits were obtained with SCU treatments, which in conjuntion with the reduction in dosage and rates justified its application.     

小麦籽粒与土壤中吡虫啉残留测定

采用高效液相色谱法,270nm波长下,对吡虫啉在小麦籽粒和土壤中的残留分析方法进行了研究,结果表明,该方法回收率为81．70％-91．34％,变异系数为2．3％～8．5％,最小检出限为0．03ng。     

吡虫啉在萝卜及土壤中的残留动态

用高效液相色谱法（HPLC）测定了吡虫啉在萝卜、萝卜叶片及其栽培土壤中的残留动态和最终残留量。结果表明：吡虫啉在萝卜、萝卜叶片和萝卜田土壤中的半衰期分别为5．65d（萝卜）、3．70d（萝叶片）和10．88d（土壤）。所测得的吡虫啉在萝卜中的最终残留量的最大值为0．075mg／kg。此值大大低于FAO规定的吡虫啉在十字花科蔬菜作物上的最低限量标准。     

咪草烟土壤残留对后茬水稻的影响

进行了大豆田除草剂咪草烟土壤残留对后茬水稻影响的小区试验。试验结果表明,水稻对咪草娴较敏感。咪草炯用量2ga．i．/hm^2前期对水稻有抑制作用,咪草娴用量4ga．i．/hm^2以下,后期抑制作用不明显,但水稻仍然减产。咪草娴用量8ga．i．/hm^2以上时,水稻减产明显。     

30%病氰硝WP在土壤及烟草中的残留分析

建立了绿色新农药病氰硝在烟草及土壤中的残留分析方法.在土壤中4.00、0.80、0.08 mg/kg三个不同添加水平的同收率为87.58%～105.96%,相对标准偏差为2.1%～8.7%.在烟叶中2.40、0.80、0.08 mg/kg三个不同添加水平的回收率为92.61%～108.14%,相对标准偏差为1.6%～5.4%.