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Search Results: 1 - 10 of 218373 matches for " 刘潇威 "
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抗氧化酶基因作为多环麝香污染分子标志物研究
陈春,周启星,
环境科学 , 2012,
Abstract: 为研究土壤中低剂量合成麝香暴露的分子毒理效应,以蚯蚓超氧化物歧化酶(SOD)和过氧化氢酶(CAT)基因为供试基因,建立mRNA表达水平的SybrGreenⅠ荧光定量PCR检测方法;并且采用自然土壤染毒实验,检测了吐纳麝香(AHTN)或佳乐麝香(HHCB)胁迫诱导SOD、CATmRNA的表达水平变化.序列同源性比较与熔解曲线分析表明设计的引物适合供试基因mRNA的检测.SOD与CAT基因构建的荧光定量标准曲线的线性关系分别为0.997和0.994,且PCR扩增效率均接近于100%,故可实现两基因mRNA表达的相对定量分析.土壤染毒暴露28d后,丙二醛(MDA)含量水平显著升高,表明自由基诱导的细胞氧化损伤是AHTN或HHCB毒性效应的主要途径方式.SOD、CATmRNA总体表现为上调表达趋势,且表达量与MDA含量呈显著正相关,表明抗氧化酶基因的诱导表达与氧化应激水平有关联.而且,SOD、CATmRNA表达水平与AHTN或HHCB浓度存在正相关剂量-效应关系.综上表明,SOD与CAT基因可成为潜在的分子生物标志物,用于表征合成麝香污染暴露水平及其毒理效应.
水体中农药与氢氧基的反应活性及持久性的关系
王一茹,长武,牛成玉,,蔡罗保,MaburySA,CrosbyDG
环境化学 , 2015,
Abstract: 农药在自然水体光化学反应中,·OH是一活跃的自由基,本文阐述了一种测定农药与·OH反应速率的方法及体系,测定了十种中国、美国水田常用农药与·OH的反应速率;在室内及中国、美国稻田条件下,测定了几种具代表性常用农药的降解速率,并与·OH反应速率进行比较.结果表明,自然水体中农药的降解速率与其·OH反应活性之间存在相关性,可用于预测农药在水体中的持久性.
二氯喹啉酸在稻田水、土壤和作物中残留动态研究
王一茹,长武,牛成玉,,蒋奇彦
环境科学 , 1996,
Abstract: 二氯喹啉酸为高效、低毒新型除草剂。在天津和吉林2年2地水田残留实验结果表明,此药在田水和茎叶中消解很快。二氯喹啉酸在田水中的半衰期分别为0.8d(天津)和2d(吉林).在茎叶中的半衰期小于1d.该农药在土壤中残留较低,消解较快,半衰期约为6d;在土壤中均未检出二氯喹啉酸代谢物。按推荐剂量421.5-525g/hm2,施药1次,施药间隔期为96-105d,糙米中二氯喹啉酸残留量均小于0.005mg/kg,远远低于最高残留限量,对人是安全的。
三维地震勘探技术在南海的应用进展及展望
Application Progress and Prospect of 3D Seismic Exploration Technology in the South China Sea
 [PDF]

,
Advances in Geosciences (AG) , 2016, DOI: 10.12677/AG.2016.61004
Abstract: 随着深水油气资源勘探开发的快速增长,深海高分辨率三维地震资料精细处理和深度处理技术越来越成熟。本文对三维地震勘探技术在南海资源勘探开发中的应用进行了总结,从海底资源勘探开发、水深地形地貌反演、深水地质灾害识别评估三个方面进行了论述,并提出了目前研究工作中尚未解决的问题及未来的发展方向和研究重点。对促进和丰富我国深海三维地震资料的深度处理与应用,深入研究和认识深海沉积与工程环境具有重要意义。
High resolution 3D seismic data of deep sea was becoming more mature with the rapid develop-ment of oil and gas exploration. In this paper, we systematically analyzed and discussed the present research concerning application progress of 3D seismic exploration technology in the South China Sea on exploration and development of marine resources, inversion of deep water depth, and identification and assessment of geological hazard in deep water. Otherwise, we put forward the unsolved problems presently, the research direction and emphasis in future. This work was instructive to promoting and enriching the deep processing and application of 3D seismic data in deep sea, and has great value of further studying and understanding sediment and engineering environment in deep sea.
加速溶剂提取-固相萃取净化-高效液相色谱法测定土壤中12种三嗪类除草剂的残留量
王小飞,,王璐,罗铭,陈珊珊,彭祎
农业环境科学学报 , 2013, DOI: 10.11654/jaes.2013.10.029
Abstract: 建立了加速溶剂(ASE)提取-固相萃取(SPE)净化-高效液相色谱(HPLC)同时检测土壤中12种三嗪类除草剂残留量的方法。土壤样品经过乙腈提取,氨基(NH2)固相萃取柱净化,高效液相色谱法-二极管阵列检测器(DAD)测定,外标法定量。12种三嗪类除草剂在0.02~2.00mg·L-1范围内线性关系良好,相关系数在0.9984~0.9999之间,方法检出限在0.004~0.005mg·kg-1之间。在0.02、0.04和0.10mg·kg-13个浓度水平,平均添加回收率在75.2%~112.7
快速溶剂(ASE)提取、凝胶渗透色谱(GPC)联合固相萃取(SPE)净化,高效液相色谱法测定土壤中的多环芳烃
张茜,,罗铭,王璐,李红,王迪,徐亚平
环境化学 , 2015,
Abstract: 建立了采用快速溶剂提取(ASE),固相萃取(SPE)与凝胶渗透色谱(GPC)协同净化方法,使用高效液相色谱-紫外-荧光检测器(HPLC-UV-FLD)串联检测土壤中多环芳烃类化合物多残留的检测方法.通过对加速溶剂提取仪提取条件,凝胶渗透色谱和固相萃取净化条件的优化,确定土壤中多环芳烃类化合物多残留的前处理方法提取溶剂为丙酮二氯甲烷(VV,5050),提取温度120℃,GPC在线浓缩系统真空腔真空度为130mbr/140mbr,弗罗里硅土固相萃取柱净化,5mL二氯甲烷作为洗脱剂.方法回收率在62.9%—118.9%之间,RSD为0.6%—19.9%.
多环麝香污染胁迫对蚯蚓特异性蛋白基因表达的影响
陈春,,郑顺安,周启星,李松
环境科学 , 2013,
Abstract: 为了探讨蚯蚓特异性蛋白基因表达在监测多环麝香低水平长期暴露污染中的应用,选择蚯蚓热休克蛋白(HSP70)、钙网蛋白(CRT)、亲环素A(cyPA)、翻译控制肿瘤蛋白(TCTP)等代表性蛋白基因作为供试基因.采用自然土壤污染模拟实验,基于mRNA表达分子水平,研究吐纳麝香(AHTN)与佳乐麝香(HHCB)长期(28d)污染胁迫对以上各特异性蛋白基因响应表达的影响.通过序列同源性比较与荧光定量PCR熔解曲线结果分析,表明设计的引物适合供试基因mRNA表达水平的检测.染毒暴露28d后,当AHTN染毒浓度小于30μg·g-1或HHCB浓度小于50μg·g-1时,蚯蚓HSP70基因表达水平无显著变化,而AHTN浓度等于或大于30μg·g-1和HHCB浓度等于或大于50μg·g-1时,HSP70基因表达水平呈显著下调趋势;而各AHTN或HHCB浓度处理组中蚯蚓CRT基因显著上调表达;cyPA和TCTP基因表达水平与对照组比较均无呈现显著性差异.研究结果表明,HSP70与CRT等基因的响应表达有望成为表征多环麝香土壤污染暴露水平及生态毒理效应的潜在生物标志物.
助剂对10%苯醚甲环唑水分散粒剂在荔枝叶片表面润湿性能的影响
Effects on wettability of 10% difenoconazole water dispersible granule with adjuvants on litchi leaves

,艳萍,王思,孙海滨
- , 2018,
Abstract: 采用接触角测量仪测定了10%苯醚甲环唑水分散粒剂(difenoconazole WG)不同倍数稀释液在荔枝叶片上的静态接触角和0~60 s动态接触角,用于计算荔枝叶片的临界表面张力和表面自由能,进而分析药液在荔枝叶片表面的润湿性能;采用全自动张力仪测定了在10%苯醚甲环唑WG不同稀释液中分别添加体积分数为0.4%的silwet stik和0.2%的as 100 2种助剂后溶液的表面张力,研究了助剂添加前后表面张力的变化。结果表明:荔枝叶片近轴面的表面自由能为23.74 mJ/m2,远轴面的表面自由能为11.89 mJ/m2,均以色散力分量(非极性分量)为主导。在10%苯醚甲环唑WG 500倍稀释液中加入体积分数为0.4%的silwet stik溶液,其表面张力为21.90 mN/m,低于荔枝叶片的临界表面张力(22.64 mN/m),且在0~10 s内接触角下降最快。研究结果表明:荔枝叶片的近轴面比远轴面更易被药液润湿;在荔枝园喷施10%苯醚甲环唑WG时,若在稀释倍数500倍的药液中添加0.4%的silwet stik助剂,则可使药液在叶片上能更快更好的润湿铺展。
The critical surface tension (CST) of litchi leaf, as well as the surface free energy (SFE), surface tension, static contact angle and dynamic contact angle in 0-60 s of diluted solution of 10% difenoconazole water dispersible granule (WG) were determined by using contact angle measuring device and automatic surface tension meter. Effects on wettability of difenoconazole WG with adjuvants (0.4% silwet stik and 0.2% as 100) on litchi leaf surface were also investigated.The results showed that the SFE value of the adaxial surface of litchi leaf was about 23.74 mJ/m2, while the SFE value of the abaxial surface was about 11.89 mJ/m2,and the dispersion component was dominant.The surface tension of 500-fold dilution of 10% difenoconazole WG with 0.4% silwet stik on litchi leaf was 21.90 mN/m, while the CST of lichi leaf was 22.64 mN/m. The contact angle of WG’s 500-fold dilution with silwet stik declined the fastest during 0-10 s.The results suggested that the adaxial surface of litchi leaf was more wettable than the abaxial surface. When 10% difenoconazole WG was applied to lichi trees,the best performance was accheived by 500-fold dilution with 0.4% silwet stik adjuvant.
噻虫嗪及其代谢物噻虫胺在节瓜中的消解动态及初步膳食风险评估
Dissipation dynamics and preliminary dietary risk assessment of thiamethoxam and clothianidin in Benincasa hispida

艳萍,王思,孙海滨,
- , 2018,
Abstract: 为明确噻虫嗪在节瓜上的残留行为,于2015年在广东和上海两地进行了噻虫嗪在节瓜上的规范田间残留试验,建立了节瓜中噻虫嗪及其代谢物噻虫胺残留量的高效液相色谱-串联质谱(HPLC-MS/MS)检测方法。样品用乙腈提取,经氨基固相萃取小柱净化,HPLC-MS/MS检测,外标法定量。结果表明:噻虫嗪在节瓜上的消解半衰期为4.98~5.84 d;采用25%噻虫嗪水分散粒剂(WG),分别按有效成分75和112.5 g/hm2的剂量于幼果期开始施药,施药2~3次,每次施药间隔期为7~10 d,距最后一次施药后3、5、7 d采样测定,节瓜中噻虫嗪和噻虫胺的残留量分别为0.010~0.422 mg/kg和<0.010~0.020 mg/kg。膳食摄入风险初步评估结果显示:其风险商值(RQ)为0.044,表明噻虫嗪的长期膳食摄入风险较低。目前中国尚未制定噻虫嗪在节瓜上的最大允许残留限量(MRL)标准,根据试验结果,建议中国可将噻虫嗪在节瓜上的MRL值暂定为1 mg/kg。
The residue behaviors of thiamethoxam in Benincasa hispida Cogn. var. chieh-qua How (chieh-qua) were investigated. The residue field trials of thiamethoxam were designed and conducted in Guangdong and Shanghai in 2015. An effective method was developed for the determination of the thiamethoxam and clothianidin. The chieh-qua samples were extracted by acetonitrile, purified with aminopropyl solid phase extraction and detected using HPLC-MS/MS (high performance liquid chromatography-tandem mass spectrometry). The dissipation and terminal residues of thiamethoxam and clothianidin in chieh-qua samples in Guangdong and Shanghai were determined based on the above analytical method. The results indicated that the half-lives of thiamethoxam in chieh-qua was 4.98-5.84 d. The chieh-qua was sprayed 2 to 3 times with 7-10 days spray interval using 25% WG at the dosage 75 and 112.5 g/hm2 during the young fruit period. The samples were collected 3 to 7 days after the last spray. The terminal residues of thiamethoxam and clothianidin were 0.010-0.422 mg/kg and <0.010-0.020 mg/kg, respectively, which were determined by the conditions above. The risk quotients (RQ) was 0.044, which revealed its low risk. According to the results, it is suggested that the MRL of thiamethoxam in chieh-qua in China should be set as 1 mg/kg.
噻唑磷在甘蔗和土壤中的残留消解动态及风险评估
Residual dynamics and risk assessment of fosthiazate in sugar cane and soil

王思,艳萍,,孙海滨
- , 2018,
Abstract: 建立了噻唑磷在甘蔗和土壤中的残留分析方法,并在广东和广西2地进行了10%噻唑磷颗粒剂在甘蔗上残留的田间试验,研究了噻唑磷在甘蔗和土壤中的消解动态和最终残留量,并对甘蔗中噻唑磷可能产生的膳食摄入风险进行了评估。甘蔗样本用乙腈提取,氨基固相萃取小柱净化,采用气相色谱-火焰光度检测器(GC-FPD)检测。结果表明:在0.01、0.1和1 mg/kg添加水平下,噻唑磷在甘蔗中的平均回收率为83%~84%,相对标准偏差(RSD)为2.6%~3.4%;在土壤中的平均回收率为84%~86%,RSD为4.1%~6.7%。噻唑磷检出限(LOD)和定量限(LOQ)均为0.01 mg/kg。田间试验结果表明:10%噻唑磷颗粒剂在广东和广西甘蔗中的消解不符合一级反应动力学方程,没有显著的消解规律,呈现的特点是浓度由小到大再变小的趋势,施药后14~21 d甘蔗中噻唑磷的残留量达到最大值0.027 mg/kg;噻唑磷在土壤中消解符合一级反应动力学方程,半衰期为8.6~9.6 d,属易降解农药;噻唑磷在甘蔗和土壤中的最终残留量均小于0.01 mg/kg。膳食摄入风险评估结果表明:甘蔗中噻唑磷对人群的急性膳食摄入风险值为225%,急性膳食摄入风险较大,还需进一步结合噻唑磷在人体内的代谢行为等数据进行综合评估;慢性膳食摄入风险值为57%,表明按照推荐剂量施用10%噻唑磷颗粒剂,慢性膳食摄入风险较低,对消费者健康是安全的。
An effective method was developed for the determination of fosthiazate residue in sugar cane and soil. Field trials were designed to evaluate the dissipation and residue of fosthiazate in sugar cane and soil in Guangdong Province and Guangxi Province. The dietary exposure and risk assessment were also conducted. The samples were extracted by acetonitrile, cleaned up by NH2-solid phase extraction and detected by GC-FPD. The results showed that, in terms of sugar cane samples, good average recoveries of 83%-84% with relative standard deviations of 2.6%-3.4% at the spiked level of 0.01, 0.1 and 1 mg/kg were achieved. As for soil samples, recoveries of 84%-86% with RSDs 4.1%-6.7% were obtained. The limit of detection (LOD) was 0.01 mg/kg and the limit of quantification (LOQ) was 0.01 mg/kg. The results demonstrated that residue of fosthiazate in sugar cane decreased first, then increased, and finally decreased again. The maximum concentration were 0.027 mg/kg which was detected 14-21 d after the application. Dissipation of fosthiazate in soil was in accordance with the first order kinetic equation with half-lives from 8.6 to 9.6 d. The terminal residue was below 0.01 mg/kg at harvest time. The acute dietary intake risk probability of fosthiazate was 225%, which was hazardous to people. It is necessary to combine the metabolic behavior data of fosthiazate in human body for comprehensive evaluation. The chronic dietary intake risk probability of fosthiazate was 57%, which was not hazardous to people.
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