oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 76 )

2018 ( 1480 )

2017 ( 1506 )

2016 ( 1607 )

Custom range...

Search Results: 1 - 10 of 57894 matches for " 马婧玮 "
All listed articles are free for downloading (OA Articles)
Page 1 /57894
Display every page Item
2%阿维菌素微乳剂在棉花和土壤中的残留分析及消解动态研究
吴绪金,李萌,周玲,马婧玮,汪红,张军锋﹡
河南农业科学 , 2014,
Abstract: 对阿维菌素在棉花和土壤中的安全性进行评价,为该农药在棉花上的合理使用提供科学依据。通过建立阿维菌素在棉籽、棉花叶和土壤中的前处理方法和液相色谱-荧光检测器的仪器方法,对阿维菌素进行定量分析;通过两地的残留试验,研究阿维菌素在棉籽、棉花叶和土壤中的残留及消解动态。结果表明,阿维菌素在棉籽、棉花叶及土壤中的空白添加平均回收率为80%~95%,相对标准偏差为2%~7%,其最小检出量为0.01ng,在棉籽、棉花叶及土壤中的最低检出浓度为0.01mg/kg。2011年和2012年河南省和湖南省两地田间残留试验结果表明,阿维菌素在棉花叶和土壤中的消解半衰期分别为0.78~1.3d、1.1~2.9d;阿维菌素在棉籽及土壤中的最终残留量均≤0.01mg/kg,说明该药为低残留、易消解农药。建议采用阿维菌素防治棉花红蜘蛛时,最高用药量为16.2g/hm2,最多施药2次,安全间隔期为21d,其在棉花上使用是安全的。
二硫代氨基甲酸盐类(dtcs)杀菌剂残留分析方法综述
马婧玮,潘灿平,张 玲,张军锋
农药学学报 , 2010,
Abstract: 综述了二硫代氨基甲酸盐类(dtcs)杀菌剂及其代谢物的残留分析研究现状,并对当前主要的残留分析方法如分光光度法、气相色谱法、液相色谱法及液相色谱-质谱联用技术和毛细管电泳法进行了较为详细的比较、分析,对dtcs类杀菌剂残留分析方法的未来发展进行了展望。衍生化液相色谱法虽然操作步骤较繁琐、耗时长,但结果稳定可靠,并能区分不同结构类型,是目前重点且被广泛采用的方法,而同时测定dtcs类杀菌剂母体及其代谢物的串联质谱方法将是今后进一步研究的热点课题。
烯效唑在棉花及土壤中的残留及消解动态
Residue and dissipation of uniconazole in Gossypium spp. and soil
马婧玮,李通,周玲,张军锋,周娟,吴绪金
- , 2017,
Abstract: 建立了烯效唑在棉花叶片、棉籽和土壤中残留的高效液相色谱-串联质谱（HPLC-MS/MS）检测方法，并运用该方法对烯效唑在棉花叶片和土壤中的残留消解规律进行了研究。样品用乙腈-水提取，经Cleanert NH2固相萃取柱净化，电喷雾正离子多反应监测模式HPLC-MS/MS检测，外标法定量。结果表明：烯效唑在棉花叶片、棉籽和土壤中的平均添加回收率在74%~101%之间，相对标准偏差（RSD）在1.2%~10%之间（n=5）。烯效唑在3种基质中的检出限（LOD）均为0.01 ng，定量限（LOQ）均为0.01 mg/kg。该方法准确、灵敏、简单，适用于棉花样品中烯效唑残留的检测。田间试验结果表明：烯效唑在棉花叶片和土壤中的消解半衰期分别为4.2~5.0 d及15.8~19.7 d；于收获期采样，烯效唑在棉籽和土壤中的最终残留量分别为<0.01 mg/kg和<0.022 mg/kg。
An analytical method with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was established to test uniconazole residues in Gossypium spp. leaves, Gossypium spp. seeds and soil. Uniconazole residue and dissipation on Gossypium spp. leaves and soil were also investigated with this method. Uniconazole residues were extracted with acetonitrile/water mixture and an aliquot of the extract was purified by a solid-phase extraction Cleanert NH2 cartridge. Finally, the analytes were measured by multiple reaction monitoring (MRM) in the electrospray positive ionization mode. The external standard method was adopted for the quantification. The results showed that the recovery rate of uniconazole in Gossypium spp. leaves, Gossypium spp. seeds and soil were between 74%-101%, with the relative standard deviations from 1.2% to 10% (n = 5). The limits of detection (LOD) of the method were 0.01 ng and the limits of quantification (LOQ) were 0.01 mg/kg for three matrices. The method is accurate, sensitive, simple and suitable for the determination of uniconazole residues in Gossypium spp. samples. Field experimental results showed that the dissipation half-lives of uniconazole in Gossypium spp. leaves and soil were 4.2-5.0 days and 15.8-19.7 days, respectively. The terminal residues at harvest in Gossypium spp. seeds and soil were lower than 0.01 mg/kg and 0.022 mg/kg, respectively.
QuEChERS-高效液相色谱-串联质谱法测定主要谷物和油料作物中氯虫苯甲酰胺的残留
QuEChERS-determination of chlorantraniliprole residues in primary grain and oilseed crops by high performance liquid chromatography-tandem mass spectrometry
马婧玮,马欢,安莉,吴家锴,汪红,祁玉峰,陈寅,吴绪金
- , 2018,
Abstract: 采用QuEChERS样品前处理方法，建立了主要谷物和油料作物产品（糙米、小麦、玉米和大豆）中氯虫苯甲酰胺残留量的高效液相色谱-串联质谱（HPLC-MS/MS）检测方法。样品经乙腈-水提取及盐析处理后，用N-丙基乙二胺（PSA）和石墨化碳黑（GCB）固相萃取填料净化，高效液相色谱-串联质谱（HPLC-MS/MS）、多反应监测模式（MRM）下测定。基质标准曲线外标法定量。结果表明：在0.005~0.5 mg/L范围内，不同样品基质中氯虫苯甲酰胺的峰面积与其相应的质量浓度间均有良好的线性关系（R2>0.99），检出限（LOD）为0.001 mg/L。在0.02、0.05、0.1和0.5 mg/kg添加水平下，氯虫苯甲酰胺在4种基质中的平均回收率在89%~114%之间，相对标准偏差（RSD）在1.3%~11%（n = 5）之间，4种基质中的最低检测浓度（LOQ）均为0.02 mg/kg。该方法适用于主要谷物和油料作物产品中氯虫苯甲酰胺残留量的检测。
A rapid, simple and efficient analytical method for the determination of chlorantraniliprole in different primary grain and oilseed crops including brown rice, wheat, maize and soybean was developed and validated based on QuEChERS and high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Chlorantraniliprole residues were extracted from primary grain and oilseed crops samples using acetonitrile-water with the addition of sodium chloride. After centrifugation, the upper solvent was cleaned-up by N-propylethyl-diamine (PSA) and graphitizing of carbon black (GCB), and determined by HPLC-MS/MS under multiple reaction monitoring mode (MRM). Sample matrix-matched calibrations were used to determine the residue contents by external standard. The calibration curves showed a good linearity in the concentration range of 0.005-0.5 mg/L for chlorantraniliprole in different sample matrix. The determination coefficients (R2) of the calibration curves were all above 0.99 and the limit of detection (LOD) was 0.001 mg/L. At fortification levels of 0.02, 0.05, 0.1 and 0.5 mg/kg in different primary grain and oilseed crop samples, recoveries ranged from 89% to 114% with relative standard deviation (RSD) of 1.3% to 11% (n = 5). The limit of quantification (LOQ) of chlorantraniliprole in brown rice, wheat, maize and soybean were all 0.02 mg/kg. This new method is applicable to detect the residues of chlorantraniliprole in different primary grain and oilseed crops.
小麦和土壤中环丙唑醇残留消解动态及膳食摄入评估
吴绪金,马婧玮,张军锋,汪 红,施烈焰,周 娟,李 通
中国生态农业学报 , 2015,
Abstract: 为评价环丙唑醇在小麦生产上应用的安全性,通过建立乙腈提取、氮磷检测器检测方法对小麦籽粒、植株和土壤样品中环丙唑醇的残留量进行检测,研究了小麦籽粒、植株和土壤中环丙唑醇的残留及其消解动态,并对小麦中的残留量进行风险评估。结果表明,环丙唑醇在小麦籽粒、植株及土壤空白样品中的添加回收率为79.2%~95.6%,相对标准偏差为1.9%~10.0%,最小检出量为8.2×10-12g,在小麦籽粒、植株及土壤中的最低检测浓度均为0.05mg·kg-1,乙腈提取、氮磷检测器检测方法重现性好,准确度、精密度高,可满足环丙唑醇在小麦上的残留分析要求。2010年和2011年,河南省、黑龙江省和江苏省3地环丙唑醇在小麦植株和土壤中的消解半衰期分别为3.0~5.5d、18.1~34.5d;不同施药次数、施药量及采样间隔,环丙唑醇在小麦籽粒中的最终残留量均≤0.415mg·kg-1。采收间隔期为14d和21d时,不同施药次数、施药剂量和采收间隔期,环丙唑醇在小麦植株、小麦籽粒和土壤中的残留量差异均不显著;采收间隔期为7d,有效成分108ghm-2施药2次与有效成分162ghm-2施药3次时小麦植株、小麦籽粒和土壤中的残留量之间均存在显著性差异。普通人群环丙唑醇的国家估算每日摄入量为0.0001099mg,占日允许摄入量的0.5%左右,按本试验方式进行施药,通常不会对一般人群健康产生不可接受的风险。
利用UPLC-TQ-MS比较蟾酥鲜品和蟾酥商品化学成分
王子月,王洪兰,周婧,马宏跃,龚艳,闫文丽,钱大玮
中国中药杂志 , 2015,
Abstract: 蟾酥为蟾蜍科动物中华大蟾蜍Bufobufogargarizans或黑框蟾蜍B.melanostictus等近缘种的耳后腺分泌的白色浆汁加工而成,近年来多用于治疗各种癌症,有一定的攻毒抗癌、消肿止痛作用。研究表明其主要抗肿瘤成分为蟾蜍二烯内酯类。蟾蜍二烯内酯有游离型和结合型2种结构。该文通过超高效液相色谱质谱联用技术(UPLC-TQ-MS)对中华大蟾蜍的蟾酥鲜品中蟾蜍二烯酸内酯类成分进行研究。采用UPLC-TQ-MS的正离子多反应监测(MRM)模式。色谱条件:ACQUITYUPLCBEHC18色谱柱(2.1mm×100mm,1.7μm),柱温35.0℃,流速0.4mL·min-1,流动相0.1%甲酸超纯水溶液-乙腈溶液。最终结合相关文献推导出蟾酥鲜品的37种蟾蜍二烯内酯成分,其中26种为游离型结构,11种为结合型结构。与蟾酥商品比较,二者之间有18种化合物存在显著差异,研究发现蟾酥的部分化学成分经加工处理后有很大的变化,7种结合型蟾蜍二烯内酯大量减少,11种游离型蟾蜍二烯酸内酯含量也随之明显改变,可能是在加工处理过程中蟾蜍二烯酸内酯部分结合型转化成了游离型。
逆固相基质分散净化和气质联机检测土壤中的六氯苯残留
张卢军,潘灿平,郝向红,赵玉珍,马婧玮,宗伏霖
农药学学报 , 2007,
Abstract: 建立了逆固相基质分散净化和气质联机法(gc-ms)快速、简便测定土壤中六氯苯(hcb)残留量的方法。以丙酮-正己烷(1∶1,体积比)为提取剂,采用超声波萃取,经固相基质psa(primarysecondaryamine)吸附净化后采用gc-ms选择离子模式检测。结果表明,六氯苯在0.05~5mg/l浓度范围内呈现出较好的线性关系,相关系数r2=0.9995;方法检测限为0.3μg/kg,定量限为0.9μg/kg,在0.89、1.78、8.90mg/kg3个添加水平上的平均回收率分别为106.6％、108.2％和108.1％。用该方法测定了天津某生产厂厂区地下1~10m深的土壤样本,发现六氯苯的残留量在2.3~25912mg/kg之间,表现出显著的空间变异趋势。该方法快速、简便、经济、高效、实用并且安全,适合大批量样本中六氯苯的快速检测。
甲基化衍生-高效液相色谱法检测代森锰锌在花生中的残留量
马婧玮,董姝君,游文宇,张敬平,钮伟民,潘灿平
农药学学报 , 2007,
Abstract: 建立了简单、快速测定花生中杀菌剂代森锰锌的残留检测方法。花生样品用l-半胱氨酸盐酸盐和edta-2na的混合溶液振荡提取,在ph=6.5~8.5时,用0.05mol/l的碘甲烷与三氯甲烷-正己烷(3∶1,体积比)的混合溶液进行甲基化反应。有机层经浓缩后,用乙腈定容,采用高效液相色谱仪在272nm处进行检测。色谱柱为agilenttc-c18,流动相为乙腈-水(50∶50,体积比),以1.0ml/min的流速等梯度洗脱。结果表明,代森锰锌的添加浓度在0.05~2.00mg/kg范围内,平均回收率为76.1%~86.2%,变异系数分别为0.7%~10.2%,均在农药残留测定所允许的范围内。该方法的最低检出限(lod)为0.02mg/kg,最低检测浓度(loq)为0.05mg/kg。
氟环唑在小麦及土壤中的残留及消解动态
Residue and dissipation of epoxiconazole in Triticum aestivum L. and soil under field conditions
吴绪金,马婧玮,汪红,周玲,李通,安莉,吴家锴,张军锋
- , 2017,
Abstract: 为了评价氟环唑在小麦生产上使用的残留安全性，建立了气相色谱-电子捕获检测器检测氟环唑在小麦植株、小麦籽粒及土壤中残留的分析方法，并对氟环唑在小麦植株、小麦籽粒和土壤中的最终残留量及小麦植株和土壤中的消解动态进行了研究。结果表明：在添加水平为0.01、0.1和2 mg/kg（小麦籽粒和土壤）和0.01、0.1和10 mg/kg（小麦植株）下，氟环唑的回收率为82%~93%，相对标准偏差为3.0%~9.7%。氟环唑在小麦植株、小麦籽粒和土壤中的定量限均为0.01 mg/kg。氟环唑在小麦植株和土壤中的消解半衰期分别为3.5~8.4和10~30 d。当以有效成分112.5 g/hm2的剂量施药2次、采收间隔期为21 d时，小麦籽粒中氟环唑的残留量为<；0.05 mg/kg，低于中国制定的小麦中氟环唑的最大残留限量值（0.05 mg/kg）。建议氟环唑在小麦上使用时最大剂量为有效成分112.5 g/hm2，施药2次，安全间隔期为21 d。
The dissipation dynamics of epoxiconazole in wheat plant and soil were evaluated, as well as the terminal residues of epoxiconazole in wheat grains, wheat plants and soil. A simple and effective analytical method for determining epoxiconazole residues in wheat grain, wheat plant and soil was established. The residue levels and dissipation rates of epoxiconazole in wheat and soil were determined by gas chromatography equipped with an electron capture detector (GC-ECD). At fortified levels of 0.01, 0.1 and 2 mg/kg in wheat grains and soil, and 0.01, 0.1 and 10 mg/kg in wheat plant, the recoveries ranged from 82% to 93%, with relative standard deviations (RSD) from 3.0% to 9.7%. The limits of quantification (LOQ) were 0.01 mg/kg for soil, wheat grains and wheat plants. The half-lives of epoxiconazole in wheat plant and in soil were 3.5-8.4 days and 10-30 days, respectively. When at the interval to harvest of 21 days，application rate of 112.5 g a.i./ha and two subsequent applications, the residue levels in wheat grain were below 0.05 mg/kg，and the terminal residues at harvest in wheat grain were lower than the maximum residue limits (0.05 mg/kg) for this pesticide set in China. When used in wheat, the following GAP was recommended: 21 days interval to harvest from last application, two maximum applications, with application rate of 112.5 g a.i./ha.
生态自我参照效应初探
The Effect of Ecological Self Reference  [PDF]
刘婷婷, 马婧瑾
Advances in Psychology (AP) , 2016, DOI: 10.12677/AP.2016.63025
Abstract:
在自我参照记忆效应中加入生态自我参照任务，探索是否存在与个体自我参照及群体参照同样的记忆优先效应。实验结果表明：以生态自我为参照的加工任务的再认成绩与语义参照加工任务的再认成绩之间并不存在显著的差异，但在R与K指标上，生态自我参照的R值显著高于语义参照，反映出了生态自我参照能够促进记忆的加工。
Joining the ecological self reference processing tasks into the self reference memory effect is to explore whether the memory is priority as that in the individual self-reference and the group- reference. The results from the experiment showed that: ecological self referential processing task and semantic processing task did not differ in recognition rates. However, “Remember” judgment rates were significantly higher in ecological self referential processing task than those in semantic processing task, which reflected the promotion of ecological self reference on memory.
Page 1 /57894
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.