高分子助剂G-103改善高效氯氟氰菊酯悬浮剂刺激性的研究

传统的高效氯氟氰菊酯制剂对施药人员的皮肤和眼睛有刺激性,容易引起过敏、中毒反应。为了解决高效氯氟氰菊酯刺激性的问题,笔者利用纳米级功能高分子助剂G-103,制备了纳米助剂包裹的低刺激性的5%高效氯氟氰菊酯悬浮剂。眼部刺激性试验结果表明,5%高效氯氟氰菊酯悬浮剂无刺激性反应。毒力试验结果表明,5%低刺激性高效氯氟氰菊酯悬浮剂24 h和48 h的LC_(50)值分别为8.599 mg/L和7.664 mg/L,显著高于对照组10%高效氯氟氰菊酯悬浮剂(24 h和48 h的LC_(50)值分别为11.050 mg/L和10.270 mg/L),表明G-103包裹提高了高效氯氟氰菊酯悬浮剂的持效性,药效得到了提升。     

螺虫乙酯的光化学降解

[目的]测定螺虫乙酯在环境介质中的光降解特性,以期为该农药合理使用准则的制定和环境安全性评价提供可靠依据。[方法]采用LC-MS/MS分析方法和恒温光解仪探讨螺虫乙酯在模拟太阳光下的光解动态。[结果]在氙灯辐射下,螺虫乙酯在p H值为5.0、7.0、9.0的3种缓冲溶液中的光解半衰期分别为3.40、3.04、5.82 h;螺虫乙酯在纯水、甲醇、乙腈和丙酮中的光解半衰期分别为4.01、7.07、12.60、22.36 h;当初始质量浓度为0.1、1.0 mg/L时,螺虫乙酯在乙腈中的光解半衰期分别为16.9、12.6 h。[结论]根据《化学农药环境安全评价试验准则》,螺虫乙酯在水和有机溶剂中分别属较易光解和较难光解类农药。     

气质联用法检测麦田中的噻虫嗪和高效氯氟氰菊酯残留

建立了噻虫嗪和高效氯氟氰菊酯残留量的气相色谱-串联质谱同时分析方法。小麦、植株和土壤样品经乙腈提取,弗罗里硅土固相萃取小柱净化,采用气相色谱-串联质谱同时分析噻虫嗪和高效氯氟氰菊酯。结果表明:噻虫嗪和高效氯氟氰菊酯在0.05~20 mg/L范围内线性良好,相关系数分别为0.997 0和0.998 0。在添加浓度为0.05~20.00 mg/kg时,噻虫嗪在小麦、植株和土壤中的平均加标回收率分别为84.0%~101.6%、76.3%~92.1%和81.2%~93.0%,相对标准偏差分别为1.6%~13.2%、10.7%~13.9%和3.5%~8.2%;高效氯氟氰菊酯在小麦、植株和土壤中的平均加标回收率分别为82.2%~108.8%、78.2%~86.1%和82.1%~91.1%,相对标准偏差分别为3.1%~9.7%、6.8%~10.0%和0.8%~7.8%。     

气相色谱法测定玉米中高效氯氟氰菊酯残留

研究了高效氯氟氰菊酯在玉米植株、土壤和玉米籽粒中残留分析方法.植株中高效氯氟氰菊酯经丙酮高速匀浆提取后,用弗罗里硅土净化、浓缩、定容后,用带BECD检测器的气相色谱仪进行测定.土壤中的高效氯氟氰菊酯用丙酮超声提取后,用二氯甲烷萃取净化、浓缩、定容后进样.玉米籽粒中的高效氯氟氰菊酯经乙腈高速匀浆提取,用弗罗里硅土/氧化铝净化、浓缩、定容后进样.高效氯氟氰菊酯的最低检出最为1.0×10-12g,在植株、土壤和籽粒中的最低检出质量分数为0.001 mg/kg.平均回收率在74.5%～108.4%之间.变异系数为2.4%～11.5%,符合残留分析要求.     

噻虫胺和高效氯氟氰菊酯对瓜蚜的毒力活性及田间防效

瓜蚜(Aphis gossypii)是一种重大农作物害虫,发生普遍且为害严重。通过室内毒力测定及田间药效试验评价噻虫胺、高效氯氟氰菊酯及其混剂对瓜蚜的杀虫活性。室内毒力测定结果表明,噻虫胺及其与高效氯氟氰菊酯的2种不同剂型混剂对瓜蚜48 h的LC50值分别为2.674 mg/L、1.411 mg/L和4.119 mg/L,其毒力活性显著高于高效氯氟氰菊酯(LC50值为42.748 mg/L)。田间药效试验结果表明,噻虫胺、高效氯氟氰菊酯及其二者的2种混剂对瓜蚜表现出优良防效,药后7 d的防效均高于83%。因此,噻虫胺、高效氯氟氰菊酯及其二者组成的混剂可用于田间瓜蚜的化学防控。     

烟碱、氯氟氰菊酯对螺旋粉虱的混配增效作用

采用浸叶法测定了烟碱和氯氟氰菊酯对螺旋粉虱的生物活性及混配增效作用.结果表明:烟碱和氯氟氰菊酯对螺旋粉虱的LC50值分别为0.0410、0.021 6 mg/L.烟碱和氯氟氰菊酯以7:1、3:1、1:2混配后,均表现为增效作用.而当烟碱:氯氟氰菊酯为3:1时,增效作用最强,此时的共毒系数最高为212.     

三种农药对中华大蟾蜍蝌蚪的急性毒性效应

农药的广泛使用是导致全球两栖动物种群衰退的主要因素之一。本实验以中华大蟾蜍(Bufo gargarizans)蝌蚪为实验材料,研究了甲基硫菌灵,高效氯氟氰菊酯,吡虫啉对中华大蟾蜍的急性毒性效应。实验结果表明,甲基硫菌灵、高效氯氟氰菊酯、吡虫啉对中华大蟾蜍(Bufo gargarizans)蝌蚪的96h半致死浓度(96h-LC50)分别为4.06 mg/L、9.84 mg/L、358.71 mg/L,安全浓度分别为0.041 mg/L、0.121 mg/L、3.58 mg/L。该结果对于进一步研究上述农药对中华大蟾蜍的慢性毒性效应奠定了基础。     

2%阿维·高氯氟水乳剂液相色谱分析

采用高效液相色谱法,以乙腈、甲醇、水为流动相,C18柱和紫外检测器同柱分离测定混剂中的阿维菌素和高效氯氟氰菊酯。结果表明,阿维菌素、高效氯氟氰菊酯的标准偏差分别为0.009,0.014;变异系数分别为1.06%,1.10%;平均回收率分别为99.9%,100.6%;线性相关系数R2阿维菌素=0.9999,R2高效氯氟氰=0.9999。     

高效氯氟氰菊酯在万寿菊中的分析方法及最终残留量研究

采用气相色谱(μ-ECD)开发了高效氯氟氰菊酯在万寿菊上的残留分析方法,利用QuChERS前处理方法,经乙腈提取、PSA净化,氮气吹干后用正己烷定容,外标法定量。高效氯氟氰菊酯在万寿菊中的添加回收率为97%～99%,相对标准偏差在4.0%～8.5%。笔者建立了万寿菊中高效氯氟氰菊酯气相色谱残留分析方法,能够满足万寿菊样品中的高效氯氟氰菊酯的定量分析,并对万寿菊高效氯氟氰菊酯最终残留量进行了检测,样品中的高效氯氟氰菊酯均未检出。     

高效氯氟氰菊酯乳油和水乳剂在大豆上的残留和降解动态

笔者研究了施药后高效氯氟氰菊酯乳油和水乳剂在大豆的叶片上的原始沉降量和降解动态规律。试验数据表明,乳油和水乳剂产品施药2 h后,高效氯氟氰菊酯在大豆叶片上的原始沉积量分别为1.386±0.214、1.167±0.132 mg/kg,在豆荚上分别为0.067±0.006、0.051±0.005 mg/kg;在叶片上的降解半衰期分别为4.1、5.2 d,在豆荚上则分别为2.8、5.0 d。药后21 d,大豆中2种剂型农药的残留量均小于0.005 mg/kg,小于最大残留限量(MRL)。相对于乳油,水乳剂在大豆叶片和豆荚上的降解速率相对较慢,尤其是在豆荚上半衰期较长,为5.2 d,可以较好地维持对大豆食心虫的防效,既高效又环境友好。研究结果为指导不同剂型的高效氯氟氰菊酯在大豆上的科学高效应用提供了理论支持。     

Determination and correlation solubility of 4-nitroimidazole in twelve pure solvents from 278.15 K to 323.15 K

In this paper, the solubility of 4-nitroimidazole in twelve pure solvents (toluene, benzene, 1,4-dioxane, acetonitrile, ethyl acetate, acetone, GBL, ethanol, methanol, n-butanol, DMF and NMP) were determined by using the laser monitoring system from 278.15 K to 323.15 K under 101.1 kPa, which are 0.00018-0.00070, 0.00021-0.00073, 0.00034-0.00092, 0.00038-0.00142, 0.00047-0.00120, 0.00126-0.00303, 0.00225-0.00517, 0.00310-0.00724, 0.00467-0.00982, 0.00453-0.01940, 0.01947-0.04652, and 0.04670-0.07452, respectively. At constant temperature, the mole fraction solubility of 4-nitroimidazole were increased as the following order: toluene < benzene < 1,4-dioxane < (ethyl acetate or acetonitrile) < acetone < GBL < ethanol < (methanol or nbutanol) < DMF < NMP, and the solubility of 4-nitroimidazole in (ethyl acetate, acetonitrile) and (methanol, n-butanol) had an intersection point at 297.55 K and 281.85 K, respectively. The solubility of 4-nitroimidazole could be increased with increasing temperature in twelve pure solvents. The ideal model, modified Apelblat equation, polynomial empirical equation, and λh equation were used to correlate the experimental values. The experimental solubility values were employed to calculate the standard dissolution enthalpy, standard dissolution entropy and Gibbs energy. The dissolution of 4-nitroimidazole could be an endothermic process in twelve pure solvents. The determination and fitting solubility of 4-nitroimidazole have important guiding significance for the purification and crystallization of its preparation process.     

Photodecomposition of gossypol by ultraviolet irradiation

Decomposition of gossypol as a thin film or as a solution by ultraviolet irradiation was studied. The decomposition of gossypol followed monophasic exponential kinetics in which the rate of decomposition varied and depended upon the irradiation condition. The lowest rate of gossypol decomposition was observed as a thin film which showed a half-life of 97 min, while the highest rate was attained as a solution in acetone as indicated by a half-life of 4.5 min. Solutions in methanol and ethanol showed relatively lower rates of decomposition with similar half-lives of approximately 50 min. Acetonitrile and chloroform solutions showed intermediate rates of decomposition for gossypol with half-lives of 15 and 19 min, respectively. Although the degradation products of gossypol were not identified, their HPLC profiles were characteristic of the solvent used. HPLC profiles of gossypol degradation products in methanol, ethanol, acetone and acetonitrile were similar, each exhibiting two peaks with variable ratios depending on the solvent and the time of exposure. The degradation products of gossypol when irradiated as a thin film and as a solution in chloroform were different from those in other solvents. In all cases, when gossypol and/or its degradation products were continuously exposed to ultraviolet radiation, they decomposed to products no longer having an aromatic structure.     

桉树叶片提取物的杀虫活性及应用初步研究

采用3种溶剂对桉树叶片进行加热回流提取,分别采用喷雾法和浸渍法测定提取物对鳞翅目害虫黏虫、半翅目害虫蚜虫及蜱螨目害虫朱砂叶螨生物活性。在初筛的基础上,对甲醇、丙酮和石油醚提取物进行了烟蚜复筛及温室盆栽试验。试验结果表明:各提取物对黏虫及朱砂叶螨在10000mg/L的浓度均未表现出杀虫活性,甲醇、丙酮和石油醚提取物对蚜虫均表现出一定的毒杀活性,对烟蚜的LC_(50)值分别为4 644.61、4 276.94、507.47 mg/L,其中石油醚提取物表现出了较高的生物活性。进行了进一步的温室盆栽验证试验,发现药后7 d,10000 mg/L的石油醚提取物对烟蚜的防效达到80.31%,有进一步研究的价值。     

Determination and correlation solubility of 4-nitroimidazole in twelve pure solvents from 278.15 K to 323.15 K

In this paper, the solubility of 4-nitroimidazole in twelve pure solvents (toluene, benzene, 1,4-dioxane, acetonitrile, ethyl acetate, acetone, GBL, ethanol, methanol, n-butanol, DMF and NMP) were determined by using the laser monitoring system from 278.15 K to 323.15 K under 101.1 kPa, which are 0.00018–0.00070, 0.00021–0.00073, 0.00034–0.00092, 0.00038–0.00142, 0.00047–0.00120, 0.00126–0.00303, 0.00225–0.00517, 0.00310–0.00724, 0.00467–0.00982, 0.00453–0.01940, 0.01947–0.04652, and 0.04670–0.07452, respectively. At constant temperature, the mole fraction solubility of 4-nitroimidazole were increased as the following order: toluene < benzene < 1,4-dioxane < (ethyl acetate or acetonitrile) < acetone < GBL < ethanol < (methanol or n-butanol) < DMF < NMP, and the solubility of 4-nitroimidazole in (ethyl acetate, acetonitrile) and (methanol, n-butanol) had an intersection point at 297.55 K and 281.85 K, respectively. The solubility of 4-nitroimidazole could be increased with increasing temperature in twelve pure solvents. The ideal model, modified Apelblat equation, polynomial empirical equation, and λh equation were used to correlate the experimental values. The experimental solubility values were employed to calculate the standard dissolution enthalpy, standard dissolution entropy and Gibbs energy. The dissolution of 4-nitroimidazole could be an endothermic process in twelve pure solvents. The determination and fitting solubility of 4-nitroimidazole have important guiding significance for the purification and crystallization of its preparation process.     

Stereocomplexation of solvent‐cast poly(lactic acid) by addition of non‐solvents

Equimolar blends of poly(L ‐lactic acid) (PLLA) and poly(D ‐lactic acid) (PDLA) were obtained by solution casting from chloroform/methanol mixed solvents and analyzed using wide‐angle X‐ray diffraction (WAXD), differential scanning calorimetry (DSC) and polarizing optical microscopy. Chloroform and methanol are a solvent and non‐solvent, respectively, for poly(lactic acid). The WAXD and DSC results showed that stereocomplex crystallization between PLLA and PDLA occurred in addition to homo‐crystallization. On adding methanol to the casting solution, the stereocomplexation was gradually enhanced while the homo‐crystallization was suppressed. When a large amount of methanol was added, the homo‐crystallization was fully suppressed and the degree of stereocomplex crystallinity reached 90%. Similar results were obtained when another non‐solvent, hexane, was added to the casting solution in place of methanol. The effect of the addition of good and poor solvents such as tetrahydrofuran, ethanol, acetone and ethyl acetate was also studied. Copyright © 2011 Society of Chemical Industry     

唑烷酮类化合物的光合成研究

通过光化学方法取代传统的金属催化等法合成重要的药物中间体唑烷酮,反应条件温和、操作简便、产率较高且污染少.同时研究了丙酮、甲醇、乙腈3种溶剂与水的不同配比对反应产物的影响.随着溶剂极性增加,立体选择性有一定提高.     

异烟肼在有机溶剂中溶解度测定及晶习研究

在283.15~323.25 K范围内，利用在线浊度法测定了异烟肼在甲醇、乙醇、正丙醇、异丙醇、正丁醇、异丁醇、丙酮、乙腈、乙酸甲酯与乙酸丁酯中的溶解度。数据表明，异烟肼在不同溶剂中的溶解度均随着温度升高而增加。在同一温度下，异烟肼的溶解度与溶剂关系符合如下顺序：甲醇 > 丙酮 > 乙醇 > 正丙醇 > 异丙醇 > 乙酸甲酯 > 异丁醇 > 正丁醇 > 乙腈 > 乙酸丁酯。采用改进的Apelblat、Wilson与NRTL方程对溶解度数据进行了拟合，结果与实验数据有较高的吻合。基于溶解度数据，对异烟肼溶解焓、溶解熵与溶解吉布斯能进行了计算，发现异烟肼溶解过程是吸热熵增过程。分析了甲醇、乙醇、正丙醇与丙酮对异烟肼冷却结晶过程所获产品晶习的影响，确定乙醇为合适的结晶溶剂。     

Effects of rosemary extracts and major constituents on lipid oxidation and soybean lipoxygenase activity

Rosemary (Rosemarinus officinalis L.) leaves were extracted with three different solvents, namely hexane, acetone and methanol. A reverse-phase high-performance liquid chromatography system in combination with a mass detector was used to quantitate the content of carnosol, carnosic acid and ursolic acid in the rosemary extracts. All rosemary extracts showed strong inhibitory effects on lipid oxidation and soybean lipoxygenase activity.     

2甲-基吡啶在丙酮-水混合溶剂中的电氧化

在质子交换膜为隔膜的电解槽内,以2甲-基吡啶为原料,在丙酮/水混合溶剂中,以PbO2为阳极,电氧化合成了2-吡啶甲酸。通过循环伏安、线性扫描伏安和恒电位电解实验,考察了丙酮与水体积比、反应温度、硫酸浓度、反应物2-甲基吡啶浓度和阳极电位对选择性和电流效率的影响。结果表明,V(丙酮)∶V(水)=3∶1,硫酸浓度1.0~1.2 mol/L,2甲-基吡啶浓度0.5 mol/L,温度30℃,阳极电位1.75~1.80 V,生成2吡-啶甲酸的选择性可达88.7%,电流效率达到48.3%。而在纯水作溶剂的溶液中,相同条件下生成2-吡啶甲酸的选择性和电流效率仅分别为67.4%和42.2%。     

Determination and correlation solubility of m-phenylenediamine in (methanol,ethanol, acetonitrile and water) and their binary solvents from 278.15 K to 313.15 K

In this study, the solubility of m-phenylenediamine in four pure solvents(methanol, ethanol, acetonitrile and water) and three binary solvent(methanol + water),(ethanol + water) and(acetonitrile + water) systems were determined in the temperature ranging from 278.15 K to 313.15 K by using the gravimetric method under atmospheric pressure. In the temperature range of 278.15 K to 313.15 K, the mole fraction solubility values of m-phenylenediamine in water, methanol, ethanol, and acetonitrile are 0.0093–0.1533, 0.1668–0.5589,0.1072–0.5356, and 0.1717–0.6438, respectively. At constant temperature and solvent composition, the mole fraction solubility of o-phenylenediamine in four pure solvents was increased as the following order:water b ethanol b methanol b acetonitrile; and in the three binary solvent mixtures could be ranked as follows:(ethanol + water) b(methanol + water) b(acetonitrile + water). The relationship between the experimental temperature and the solubility of m-phenylenediamine was revealed as follows: the solubility of mphenylenediamine in pure and binary solvents could be increased with the increase of temperature. The experimental values were correlated with the Jouyban–Acree model, van't Hoff–Jouyban–Acree model, modified Apelblat–Jouyban–Acree model, Sun model and Ma model. The standard dissolution enthalpy, standard dissolution entropy and the Gibbs energy were calculated based on the experimental solubility data. In the binary solvent mixtures, the dissolution of m-phenylenediamine could be an endothermic process. The solubility data,correlation equations and thermodynamic property obtained from this study would be invoked as basic data and models regarding the purification and crystallization process of m-phenylenediamine.