高浓度90%莠去津水分散粒剂的研制

介绍了高浓度90%莠去津水分散粒剂(WG)的制备,并确定了优惠配方,简述了该剂型的特点、配方组成、加工工艺、贮存稳定性以及性能测定。试验结果表明该产品的各项指标符合水分散性粒剂的要求,如悬浮率在90%以上,崩解时间在1min以内,在(54±2)℃下贮存4周后的分解率小于5%,且产品的各项指标均符合水分散粒剂的要求。     

莠去津、2,4-滴丁酯和烟嘧磺隆的复配效应

用培养皿法和盆栽喷雾法分别测定了烟嘧磺隆＋莠去津、烟嘧磺隆＋2，4-滴丁酯混用后的联合作用类型。结果表明：烟嘧磺隆＋莠去津对小麦芽长的相互作用为相加作用，对藜和狗尾草稍有增效作用；烟嘧磺隆＋2，4-滴丁酯对小麦芽长的相互作用为增效作用，对藜和狗尾草的相互作用为增效作用。     

Comparison of algal assay systems for detecting waterborne herbicides and metals

The EPA Bottle Test was compared to a short-term algal bioassay method (Oxygen Evolution Assay) for detecting waterborne herbicides and metals. Although the Bottle Test proved to be a more sensitive assay system, the responses of the two bioassays correlated well. The Oxygen Evolution Assay may be useful as a rapid preliminary screening method for determining which chemicals should undergo further testing. In both bioassays, differences were observed in the results of experiments conducted in the standard algal growth medium and in nutrient-enriched water samples, suggesting that water chemistry plays an important role in the determination of specific toxicity thresholds for algae.     

Preliminary studies in removing atrazine,isoproturon and imidacloprid from water by natural sepiolite

Sepiolite is a hydrated magnesium silicate clay with a fibrous structure and binder properties. To calculate the potential use of sepiolite in removing atrazine [2‐chloro‐4‐ethylamino‐6‐isopropilamino‐1,3,5,‐triazine], isoproturon [3‐(4‐isopropylphenyl)‐1,1‐dimethylurea] and imidacloprid [1‐(6‐chloro‐3‐pyridinylmethyl)‐N‐nitroimidazolin‐2‐ylideneamine] from water, the adsorption of atrazine, isoproturon and imidacloprid on sepiolite desiccated at 110 °C from aqueous solution at 25 °C has been studied by using batch experiments. In addition, column experiments were carried out with the sepiolite sample using aqueous solutions of atrazine, isoproturon and imidacloprid at a concentration of 20.0 × 10⁻⁴ cmol dm⁻³. The experimental data points have been fitted to the Langmuir equation to calculate the adsorption capacities (X_m). Values for X_m ranged from 2.70 × 10⁻¹ cmol kg⁻¹ for isoproturon up to 3.97 × 10⁻¹ cmol kg⁻¹ for atrazine. The removal efficiency (R) ranged from 36.7% for isoproturon up to 74.3% for atrazine. The batch experiments show that the sepiolite is more effective in adsorbing atrazine than imidacloprid and isoproturon. The column experiments show that sepiolite might be reasonably used in removing atrazine, the column efficiency being 46%. The data indicate that a readily available and inexpensive Spanish sepiolite can be employed as a filter for contaminated waters with these pesticides, controlling their release to the environment. © 1999 Society of Chemical Industry     

超高效液相色谱-串联质谱法同时测定水中的呋喃丹、莠去津和微囊藻毒素

目的建立同时测定水中的呋喃丹、莠去津和微囊藻毒素-LR的超高效液相色谱-串联质谱方法。方法样品直接过0.22μm的水系滤膜,以0.1%甲酸水溶液(A)和乙腈(B)为流动相经BEH C18柱(100 mm×2.1 mm,1.7μm)梯度洗脱分离,串联四极杆质谱在电喷雾正离子(electrospray ionization,ESI+)模式下同时测定呋喃丹、莠去津和微囊藻毒素-LR的含量。结果呋喃丹、莠去津和微囊藻毒素-LR在0.5~50 ng/m L范围内线性良好,r≥0.999,平均加标回收率90.2%~99.5%,精密度为2.1%~4.5%。结论本方法操作简单、灵敏度高、线性范围宽、结果准确可靠,可用于水中的呋喃丹、莠去津和微囊藻毒素-LR的同时测定。     

固相萃取-高效液相色谱法测定水中灭草松、莠去津和2,4-滴

采用固相萃取富集-高效液相色谱法[1]分析地表水与饮用水中的灭草松,莠去津与2,4-滴。液相色谱条件为V甲醇∶V纯水=60∶40、流速为0.8 mL/min、柱温为30℃、检测波长为225 nm。灭草松、莠去津、2,4-滴检出限分别为0.002 5、0.000 2、0.002 5mg/L,回收率分别为85%-115%、80%-120%和85%-115%。该方法较样品衍生化后用气相色谱法测定简便,可实际应用于水质检测工作。     

紫外/过氧化氢（UV/H2O2）高级氧化工艺在饮用水处理中的应用

通过砂滤池出水后接UV/H2O2高级氧化中试试验设备并投加特征污染物,考察了UV,UV+颗粒活性炭(GAC),UV/H2O2,UV/H2O2+GAC工艺对阿特拉津、嗅味物质及消毒副产物生成量的去除效果,发现UV/H2O2+GAC工艺对土臭素去除效果最好,去除率高达95%以上;对MIB和阿特拉津的去除效果比较接近,去除率在70%以上;UV/H2O2能有效去除消毒副产物前体物、减少消毒副产物的生成。     

固相萃取-HPLC法同时测定大米中甲萘威和阿特拉津

建立固相萃取-高效液相色谱二极管阵列检测器(DAD)法同时测定大米中甲萘威和阿特拉津的方法。样品经乙腈提取、净化、旋转蒸发和氮吹浓缩后,用甲醇定容至2 mL,通过XDB-C₁₈(250 mm×4.6 mm,5μm)色谱柱分离,流动相采用甲醇-水(60︰40,V/V),流速0.4 mL/min,柱温40℃,进样量5μL,在220 nm波长下测定。结果表明,在0~2.0μg/mL范围内,甲萘威和阿特拉津呈现良好线性关系,相关系数(R2)均为1.000,检出限分别为1.0μg/kg和3.0μg/kg。对0.2,0.4和0.8 mg/kg这3种不同浓度下甲萘威和阿特拉津准确度和精密度试验,回收率分别为88.3%~102.2%和87.5%~104.3%,相对标准偏差(RSD,n=6)分别为1.2%~3.3%和2.3%~4.7%。试验方法稳定性好、操作简单、灵敏度高,可满足于大米中甲萘威和阿特拉津测定。     

气相色谱法测定玉米中乙草胺·莠去津·2,4-滴丁酯残留

[目的]为建立乙草胺、莠去津、2,4-滴丁酯在玉米植株和籽粒中的残留分析方法,采用丙酮和乙酸乙酯混合溶剂提取,凝胶色谱仪净化,气相色谱电子捕获检测器检测.[结果]乙草胺最小检出量为1.0×10-12g,最低检出质量分数为0.005 mg/kg,平均回收率在80.3％～108.5％之间,相对标准偏差均小于10％;莠去津最小检出量为1.0×10-12 g,最低检出质量分数为0.01 mg/kg,平均回收率在86.3％～112.4％之间,相对标准偏差均小于14％;2,4-滴丁酯最小检出量为1.0×10-12g,最低检出质量分数为0.002 mg/kg,2,4-滴丁酯回收率为78.0％～108.0％,相对标准偏差均小于14％.[结论]方法具有简便、准确的特点,符合残留分析要求.