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为研究棉田除草剂溴嘧氯草醚(开发代号SIOC0426,化学名称为N-[2-氯-6-(4,6-二甲氧基-2-嘧啶氧基)苄基]-4-溴苯胺)的中试合成工艺,以2-氟-6-氯苯甲醛为起始原料,通过水解、缩合、还原和亲核取代反应在公斤级规模上合成了溴嘧氯草醚,用高效液相色谱外标法测定了原药含量,通过三维高效液相色谱-质谱联用(HPLC-DAD-MS)技术对原药中的杂质结构进行了鉴定。结果表明,反应总收率高于80%,原药含量大于98%,主要杂质为未反应完全的中间体2-[(4-溴苯氨基)甲基]-3-氯苯酚和溴嘧氯草醚Smiles重排产物。该工艺反应条件温和,反应收率高,原药含量高,"三废"排放较少,较适合工业化放大生产。 相似文献
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《农药科学与管理》2003,(10)
中文通用名称:磺草酮英文通用名称:sulcotrione农药登记名称及商品名称:15%磺草酮水剂(玉草施)理化性质:磺草酮原药(含量≥90%)外观为淡咖啡色颗粒状固体。熔点:139℃;蒸气压(25℃):5×10-3mPa;溶解度:25℃水中为165mg/L,溶于丙酮和氯仿。在水中、日光或避光下稳定,80℃以下稳定。化学名称:2-(2-氯-4-甲磺酰苯甲酰)环己烷-1,3-二酮。结构式:毒性:磺草酮原药大鼠急性经口LD50>4640mg/kg,急性经皮LD50>2150mg/kg;对皮肤无刺激性,对眼睛轻度刺激性;对皮肤无致敏作用;致突变试验:Ames试验,小鼠骨髓微核试验均为阴性;90d大鼠喂饲亚慢性试验最… 相似文献
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本文采用气-质联用(GC—MS)法对乙氧氟草醚原药及其原药中的杂质进行分析鉴定，了解乙氧氟草醚原药中的杂质情况和质量状况，并结合合成路线，分析产生杂质原因，用以指导工业生产。 相似文献
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本文通过采用气质联用(GC—MS)法对莠去津原药中莠去津及其它杂质进行分析鉴定，从而了解莠去津原药中的杂质情况和质量状况，用以指导工业生产。 相似文献
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为了创制高效广谱的绿色杀虫剂,以(E)-4,5-二氢-6-甲基-4-(3-吡啶亚甲基氨基)-1,2,4-三嗪-3(2H)-酮(吡蚜酮)为先导,用带有不同电荷密度的五元、六元取代苯环或杂环取代其结构中的吡啶环部分,合成了10个全新的嘧啶酮类衍生物,特别对其中所包含的三嗪环和二氢喹唑啉酮合成部分进行了重点研究。所有目标化合物的结构均经过核磁共振氢谱、高分辨质谱及红外光谱的确认。初步杀虫活性测试结果表明,目标化合物对蚜虫Aphis craccivora未表现出明显的杀虫活性,初步暗示了先导化合物吡蚜酮结构中所含的吡啶环部分可能对其杀虫活性起了重要作用。 相似文献
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本文采用高效液相色谱-质谱-质谱联用法对烯草酮样品进行分离分析.得到烯草酮及其6种杂质的一级、二级质谱图,并总结烯草酮各杂质的结构,计算准确分子量.有助于烯草酮杂质的分析,有利于控制烯草酮原药中的杂质. 相似文献
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The effect of the malathion impurities, isomalathion of O,S,S-trimethyl phosphorodithioate (OSS-Me), on the toxicokinetic behavior of [methoxy-14C]malathion in female rats was investigated. Malathion α- and β-monoacids and the diacid were the predominant metabolites in the blood of rats pretreated orally with corn oil followed 4 hr later with radiolabeled malathion. Pretreatment of rats with isomalathion or OSS-Me in corn oil followed by treatment with malathion resulted in a decrease of total radioactive metabolites in the blood. Moreover, a substantial reduction in the level of malathion β-monoacid and malathion diacid was observed in the blood of impurity pretreated animals. These results indicate that the impurities have a stronger effect in inhibiting carboxylesterases which preferentially hydrolyze the β-carboethoxy moiety of malathion. The major malathion metabolites excreted in the urine of pretreated and control rats generally matched those present in the blood. The potentiation of the acute toxicity of malathion by pretreatment with isomalathion or OSS-Me may be explained by the reduction in the rat's capacity to degrade malathion via carboxylesterase-catalyzed hydrolysis of the β-carboethoxy moiety. 相似文献
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Gas and liquid chromatographic methods were evaluated for determining the impurities in technical grade fenitrothion (≥95%). These impurities were S-methyl fenitrothion. fenitrooxon, bis-fenitrothion, S-methyl-bis-fenitrothion and 3-methyl-4-nitrophenol. The GC proved to be insensitive to the two bis compounds whereas these compounds could be analysed by liquid chromatography on a Corasil 11 column or on an OPN column. Nine technical samples were analysed and S-methyl fenitrothion, a potent anticholinesterase agent, was by far the most common impurity. 相似文献
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The penetration of two model seed oil compounds, [14C]triolein (TRI) and [14C]methyl oleate (MEO) through plant cuticles and their effects on the penetration of [14C]quizalofop-ethyl and [14C]fenoxaprop-ethyl were investigated. Experiments were carried out using isolated cuticles from rubber plant (Ficus elastica Roxb.) leaves and from tomato (Lycopersicon esculentum Mill,) and pepper (Capsicum annuum L.) fruits. Chemicals were deposited in droplets on to cuticle discs maintained on agar blocks under controlled conditions. TRI and MEO were used at 1% (V/V). The transfer of radiolabel through cuticles was negligible for TRI and varied from 6 to 13% after 72 h, according to species, for MEO, The penetration results obtained for quizalofop-ethyl (0.084 mg mL-1) and fenoxaprop-ethyl (0.189 mg mL-1) were very similar and varied according to species. The greatest diffusion intoagar was observed for pepper (12.8% and 10.7% after 72 h, for quizalofop-ethyl and fenoxaprop-ethyl respectively), the lowest for rubber plant cuticles (1.4 and 1.3% respectively). Addition of MEO produced significant increases in the penetration of quizalofop-ethyl and fenoxaprop-ethyl through rubber plant and tomato cuticles. TRI had an enhancing effect on the two herbicides only with rubber plant cuticles. Results are discussed with particular consideration of the variations between plant species and the possible mode of action of seed oil adjuvants. 相似文献
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The degradation of diuron photoinduced by iron(III) in aqueous solution has been investigated with different iron(III) species (monomeric species Fe(OH)2+, dimeric species Fe2(OH)24+ and water-soluble oligomeric species) under monochromatic excitation at 365 nm and under sunlight. The rate of degradation depends on the concentration in Fe(OH)2+, the most reactive species in terms of •OH radical formation. The major photoproduct is 3-(3,4-dichlorophenyl)-1-formyl-1-methylurea which represents more than 60% of diuron disappearance. The mechanism only involves the attack by •OH radicals arising from iron(III) excited species. The half-lives of diuron when submitted to such a process in the environment were estimated to be 1–2 h and a few days according to the concentration of Fe(OH)2+ (respectively 70% and <10% of total iron(III) concentration). 相似文献
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Balcer JL DeAmicis CV Johnson PL Klosin J Whiteker GT Rao CS Dai D 《Pest management science》2011,67(5):556-559
BACKGROUND: Tricyclazole is a commercial fungicide used to control rice blast. As part of re‐registration activities, samples of metabolites and process impurities are required. In addition, isotopically labeled tricyclazole samples are also required. RESULTS: Four new compounds related to tricyclazole are reported. An isotopically labeled sample of tricyclazole was prepared that contained two 15N atoms and one 13C atom. Radiolabeled tricyclazole with 14C at the triazole C3 position was also synthesized. A new process impurity in technical tricyclazole was identified and synthesized. A new metabolite of tricyclazole was identified, independently synthesized and characterized by X‐ray crystallography. CONCLUSION: A previously unreported metabolite of tricyclazole has been identified and structurally characterized. In addition, a new process impurity has been identified by independent synthesis. Identification of these new compounds has facilitated the continued registration of this important fungicide. Copyright © 2011 Society of Chemical Industry 相似文献
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运用3S技术,并采用最大似然法分别对1989年和2010年渭干河-库车河绿洲两期Landsat-TM影像数据进行分类统计,获得了该区域22年来土地利用/土地覆被变化矢量图和定量统计数据,并利用不同时期该流域地表径流和地下水资源开发利用程度、农业种植结构、城市用水、天然植被用水,分析该区域土地类型变化和水资源的关系。研究结果表明：该地区耕地面积逐年增加,22年来增加耕地面积141 573.4 hm2,平均每年增加6741.59 hm2;天然植被草地面积急剧减少,平均每年减少7 682.38 hm2,城市用水由0.41亿m3增加至4.26亿m3,加之机电井数量骤增导致地下水位下降了2.34 m;导致地下水位下降,水质矿化度增高,天然植被大量减少,流域下游生态问题极其脆弱。 相似文献
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H. R. Forrer J. C. Zadoks 《European journal of plant pathology / European Foundation for Plant Pathology》1983,89(3):87-98
In 1980, field inoculations withSeptoria tritici were performed on winter wheat cv. Okapi. Leaf necrosis progress curves were established; they were sigmoid and could be transformed into logit lines. There was a great difference in the slope of the logit lines between inoculated plots and non-inoculated controls. The mid-time values varied according to inoculum dosage and post-inoculation humidity treatment. Yields (kg ha?1) and average grain weights (mg grain?1) differed significantly between inoculated and non-inoculated plots, but seldom among inoculation treatments. Decrease of average grain weight completely explained yield loss, which was 878 kg ha?1 or 12% of control (7045 kg ha?1). This crop loss is considerable for a cultivar which is not particularly susceptible. A good correlation was found between the amount of necrosis at development stages DC=75 and 77 and yield depression. The integral of necrosis over time gave a high correlation with loss of kernel weight. 相似文献
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Field experiments involving eight cultivars were conducted in 1998 and 16 cultivars in 1999 to study the ability of rice (Oryza sativa L.) to suppress Monochoria vaginalis (Burm. f ) Kunth through light competition. Dry weights of M. vaginalis shoots in early season culture exceeded those in normal season culture of any rice cultivars. The relative photosynthetic photon flux density (R‐PPFD), which was calculated as the ratio of the photosynthetic photon flux density (PPFD) below the rice canopy to that measured above the rice canopy, varied according to rice cultivar. A strong linear correlation was observed between the mean R‐PPFD at 29–35 days after transplanting (DAT) (r2 = 0.80; p < 0.01 in 1998; r2 = 0.63, p < 0.001; and r2 = 0.93, p < 0.001 in 1999), or 36–42 DAT (r2 = 0.66, p < 0.05 in 1998; r2 = 0.72, p < 0.001; and r2 = 0.97, p < 0.001 in 1999), and the dry weight of M. vaginalis shoots at approximately 60 DAT. Data from the three experiments could be pooled into one regression line because intercepts and regression coefficients were not significantly different. The r2 values of the combined regression were highest when R‐PPFD was expressed as the mean of measurements taken during 14 days (from 29 to 42 DAT; r2 = 0.81, p < 0.001). The shortest period for measuring mean R‐PPFD in order to obtain a meaningful relationship with M. vaginalis shoot dry weight was 7 days (from 29 to 35 DAT; r2 = 0.78, p < 0.001). For that same period, relationships between M. vaginalis shoot dry weight at 60 DAT and rice tiller number or leaf area index (LAI) at ground level were weak. However, there were negative relationships between M. vaginalis shoot dry weights at 60 DAT and rice LAI measured 20 cm above the ground, plant heights or rice shoot dry weight, but these coefficients of determination were smaller than those calculated by R‐PPFD for the same period. Thus, the ability of rice to suppress M. vaginalis can be evaluated more accurately by measuring mean R‐PPFD below the rice canopy for 7 days (from 29 to 35 DAT) than by measuring rice LAI, plant height and shoot dry weight. 相似文献
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于2018—2019年以44份不同抗倒性的白菜型冬油品系(种)为试材,依据改良倒伏系数(ILC)法对其抗倒伏性进行聚类分析和评价,探讨白菜型冬油菜株型、茎秆力学特性、干物质积累量等对其倒伏性的影响。结果表明:依据ILC可将白菜型冬油菜参试材料聚为3类:Ⅰ类为强抗倒性材料,包含2个品系(种);Ⅱ类为中等抗倒性材料,包含15个品系(种);Ⅲ类材料抗倒性最弱,包含27个品系(种)。聚类结果与田间倒伏分级结果基本吻合,两者呈极显著正相关(r=0.452~(**)),表明利用ILC评价白菜型冬油菜的抗倒伏性具有可靠性。与Ⅱ类、Ⅲ类材料相比,抗倒性强的Ⅰ类材料株高显著变矮,重心高度显著降低,其平均株高和重心高度比倒伏Ⅲ类材料分别降低19.8 cm和17.8 cm。白菜型冬油菜茎秆抗折力在三类材料间均存在显著差异,抗倒伏Ⅰ类参试材料平均茎秆抗折力是Ⅲ类材料的2.59倍。白菜型冬油菜倒伏系数与株高(r=0.346~*)、地上部鲜质量(r=0.344~*)、重心高度(r=0.579~*)呈显著正相关,与茎秆抗折力(r=-0.518~*)呈显著负相关。与Ⅱ类、Ⅲ类材料相比,Ⅰ类参试材料根长增长38%～41%,根鲜质量增大71%～102%,分枝部位降低32%～44%,一次分枝数增加10%左右、单株角果数增加30%～38%、角果长度增长1%左右、每角粒数增加11%～14%,千粒重增加21%～23%。白菜型冬油菜参试材料抗倒伏性存在显著差异,植株高度、重心高度、地上部鲜质量、茎秆抗折力等是影响其抗倒伏性的关键因素,株高较小、重心高度较低、茎秆抗折力大的白菜型冬油菜品种更高产抗倒伏。 相似文献