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QuEChERS-高效液相色谱法测定绿茶中虫螨腈残留 被引量:16
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作者 王兵 李斌 +2 位作者 张媛媛 张卓 陈忠正 《中国食品学报》 EI CAS CSCD 北大核心 2017年第1期240-245,共6页
建立了绿茶中虫螨腈残留的高效液相色谱快速分析方法。茶叶样品经乙腈提取,超声辅助萃取,以N-丙基乙二胺(PSA)、C18和石墨化炭黑(GCB)进行净化,经C18色谱柱分离,甲醇和水洗脱,采用高效液相色谱-二极管阵列检测器检测。结果表明:虫螨腈... 建立了绿茶中虫螨腈残留的高效液相色谱快速分析方法。茶叶样品经乙腈提取,超声辅助萃取,以N-丙基乙二胺(PSA)、C18和石墨化炭黑(GCB)进行净化,经C18色谱柱分离,甲醇和水洗脱,采用高效液相色谱-二极管阵列检测器检测。结果表明:虫螨腈在质量浓度0.4~20.0 mg/L范围,其响应值呈线性关系,相关系数为0.9999;在0.1,1,5 mg/kg 3种加标水平下平均回收率为89.5%~99.9%,相对标准偏差(n=6)为2.7%~5.9%。此方法的检测限为0.04 mg/kg,定量限为0.08 mg/kg。 展开更多
关键词 虫螨腈 茶叶 QUECHERS 高效液相色谱
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Modeling the land surface reflectance for optical remote sensing data in rugged terrain 被引量:12
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作者 WEN JianGuang LIU QinHuo +2 位作者 XIAO Qing LIU Qiang LI XiaoWen 《Science China Earth Sciences》 SCIE EI CAS 2008年第8期1169-1178,共10页
A model for topographic correction and land surface reflectance estimation for optical remote sensing data in rugged terrian is presented.Considering a directional-directional reflectance that is used for direct solar... A model for topographic correction and land surface reflectance estimation for optical remote sensing data in rugged terrian is presented.Considering a directional-directional reflectance that is used for direct solar irradiance correction and a hemispheric-directional reflectance that is used for atmospheric diffuse irradiance and terrain background reflected irradiance correction respectively,the directional reflectance-based model for topographic effects removing and land surface reflectance calculation is developed by deducing the directional reflectance with topographic effects and using a radiative transfer model.A canopy reflectance simulated by GOMS model and Landsat/TM raw data covering Jiangxi rugged area were taken to validate the performance of the model presented in the paper.The validation results show that the model presented here has a remarkable ability to correct topography and estimate land surface reflectance and also provides a technique method for sequently quantitative remote sensing application in terrain area. 展开更多
关键词 bidirectional reflectance topographic/atmospheric correction SKY DIFFUSE IRRADIANCE ADJACENT terrain-reflected IRRADIANCE rugged area
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Distributed modeling of monthly air temperatures over the rugged terrain of the Yellow River Basin 被引量:12
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作者 ZENG Yan QIU XinFa +2 位作者 HE YongJian SHI GuoPing LIU ChangMing 《Science China Earth Sciences》 SCIE EI CAS 2009年第5期694-707,共14页
Our analyses of the monthly mean air temperature of meteorological stations show that altitude, global solar radiation and surface effective radiation have a significant impact on air temperature. We set up a physical... Our analyses of the monthly mean air temperature of meteorological stations show that altitude, global solar radiation and surface effective radiation have a significant impact on air temperature. We set up a physically-based empirical model for monthly air temperature simulation. Combined the proposed model with the distributed modeling results of global solar radiation and routine meteorological observation data, we also developed a method for the distributed simulation of monthly air temperatures over rugged terrain. Spatial distribution maps are generated at a resolution of 1 km×1 km for the monthly mean, the monthly mean maximum and the monthly mean minimum air temperatures for the Yellow River Basin. Analysis shows that the simulation results reflect to a considerable extent the macro and local distribution characteristics of air temperature. Cross-validation shows that the proposed model displays good stability with mean absolute bias errors of 0.19°C–0.35°C. Tests carried out on local meteorological station data and case year data show that the model has good spatial and temporal simulation capacity. The proposed model solely uses routine meteorological data and can be applied easily to other regions. 展开更多
关键词 YELLOW RIVER BASIN MONTHLY mean air temperature rugged TERRAIN DISTRIBUTED modeling
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加固计算机板卡振动分析与设计 被引量:9
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作者 徐立颖 《计算机工程与设计》 CSCD 北大核心 2008年第10期2635-2639,共5页
传统意义下印制电路板的振动分析与设计主要是针对从电子元器件选型开展的,并不适用于商用计算机的加固技术。对商用计算机的板卡进行有效的加固设计,使其满足在振动环境下的使用要求,一直是计算机加固技术的重点。针对加固计算机板卡... 传统意义下印制电路板的振动分析与设计主要是针对从电子元器件选型开展的,并不适用于商用计算机的加固技术。对商用计算机的板卡进行有效的加固设计,使其满足在振动环境下的使用要求,一直是计算机加固技术的重点。针对加固计算机板卡开展的振动分析表明,已有的加固技术并不能降低恶劣环境下板卡的振动位移,解决该问题必须采用全新的加固思路。商用计算机板卡的最新加固方案在理论分析方面和工程应用方面均表明是有效可行的,具有广泛的推广价值。 展开更多
关键词 振动 加固 分析 有限元 印制板
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High Efficient Extraction of Phthalates in Aquatic Products by a Modified QuEChERS Method 被引量:7
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作者 WANG Wen-wen GAO Fu-kai LI Gui-zhi LIU Zhen-bo LIU Yong-ming 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2013年第4期653-656,共4页
A simple, environmentally friendly and high efficient extraction method was proposed for the determina- tion of five phthalates in aquatic products by gas chromatography combined with mass spectrometry detector (GC-M... A simple, environmentally friendly and high efficient extraction method was proposed for the determina- tion of five phthalates in aquatic products by gas chromatography combined with mass spectrometry detector (GC-MS). When this method was adopted, samples were pretreated by modified QuEChERS(quick, easy, cheap, effective, rugged and safe) method. An environmentally friendly extractant(ethanol aqueous solution) replaced toxic acetonitrile for extracting phthalates in the protein-matrix samples. Fluorescence quenching spectra of bovine serum albumin(BSA) with phthalates show that there was a high-affinity interaction between phthalate and protein, de- creasing the extraction efficiency of phthalates from fish samples. However, in the 80%(volume fraction, ~) ethanol aqueous solution, a slow but full protein denaturation takes place, which would cause the unfolding of protein and the release of phthalates. Meanwhile, the fat-soluble impurities are extracted less in ^(ethanol) 80% aqueous solution than in either ~p(ethanol) 100% or hydrophobic solvents in the liquid-liquid extraction procedure. Therefore the puri- fication steps were greatly simplified. Overall recoveries were 81.77%--90.5% with limits of detection between 2.53 and 9.61 ~tg/L, and relative standard deviation values at 1.15%---4.85%. The proposed approach was satisfactorily applied to the determination of phthalates in real aquatic products, such as fish, shrimp and oyster. 展开更多
关键词 PHTHALATE Modified quick easy cheap effective rugged and safe(QuEChERS) method Protein Aquatic product Gas chromatography-mass spectrometry-selected ion monitoring(GC-MS-SIM)
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QuEChERS前处理结合HPLC-MS/MS同时测定原料乳中30种兽药残留 被引量:7
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作者 李婧妍 韩波 +1 位作者 安乐 张瑞雪 《食品研究与开发》 CAS 北大核心 2022年第9期176-185,共10页
建立快速、简便、低价、有效、稳定、安全(quick、easy、cheap、effective、rugged、safe,QuEChERS)前处理结合高效液相色谱-串联质谱技术同时测定原料乳中β-激动剂、喹诺酮和磺胺类30种兽药残留的分析方法。样品经酸化乙腈溶液和乙二... 建立快速、简便、低价、有效、稳定、安全(quick、easy、cheap、effective、rugged、safe,QuEChERS)前处理结合高效液相色谱-串联质谱技术同时测定原料乳中β-激动剂、喹诺酮和磺胺类30种兽药残留的分析方法。样品经酸化乙腈溶液和乙二胺四乙酸-Mcllvaine缓冲液提取,盐析后的乙腈相用十八烷基硅烷和N-丙基乙二胺净化剂分散固相萃取净化,在电喷雾正离子多反应监测模式下进行测定。30种兽药在0.5μg/kg~100.0μg/kg线性关系良好,相关系数(r)>0.99。方法检出限和定量限分别为0.10μg/kg~1.21μg/kg和0.28μg/kg~4.05μg/kg。在5.0、10.0、20.0μg/kg加标水平时,回收率为71.1%~94.8%,相对标准偏差均低于12.2%。该方法准确可靠、灵敏度高,可用于原料乳中β-激动剂、喹诺酮和磺胺类兽药残留的定量分析。 展开更多
关键词 兽药残留 原料乳 QuEChERS提取法 高效液相色谱-串联质谱法 基质效应
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QuEChERS-UPLC-MS/MS检测畜禽组织中金刚烷胺残留 被引量:6
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作者 李彦 关丽丽 +6 位作者 牟妍 孙磊丽 梁君妮 沙美兰 邹文晓 孙爱丽 曹鹏 《食品研究与开发》 CAS 北大核心 2013年第23期37-40,共4页
建立一种QuEChERS-超高效液相色谱-串联质谱(QuEChERS-UPLC-MS/MS)检测畜禽组织中金刚烷胺残留的方法。样品用1%乙酸乙腈溶液超声提取,提取液加入C18和PSA填料进行基质分散固相净化,浓缩后经Proshell120 EC-C18柱分离,用电喷雾离子源正... 建立一种QuEChERS-超高效液相色谱-串联质谱(QuEChERS-UPLC-MS/MS)检测畜禽组织中金刚烷胺残留的方法。样品用1%乙酸乙腈溶液超声提取,提取液加入C18和PSA填料进行基质分散固相净化,浓缩后经Proshell120 EC-C18柱分离,用电喷雾离子源正离子多反应监测(MRM)模式进行检测。在0.2μg/L^100.0μg/L线性范围内具有较好的线性关系,相关系数大于0.997。该方法检出限(LOD)为0.6μg/kg,定量限(LOQ)为2.0μg/kg,回收率为70.5%~100.1%,相对标准偏差(RSD)小于10%。该方法简便快速、准确度好,适用于畜禽组织中金刚烷胺药物残留的检测。 展开更多
关键词 Quick Easy Cheap rugged Safe(QuEChERS) 超高效液相色谱串联质谱 金刚烷胺 畜禽组织 Quick Easy Cheap rugged Safe (QuEChERS)
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Plane-Wave Least-Squares Reverse Time Migration for Rugged Topography 被引量:6
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作者 Jianping Huang Chuang Li +1 位作者 Rongrong Wang Qingyang Li 《Journal of Earth Science》 SCIE CAS CSCD 2015年第4期471-480,共10页
We present a method based on least-squares reverse time migration with plane-wave encoding (P-LSRTM) for rugged topography. Instead of modifying the wave field before migration, we modify the plane-wave encoding fun... We present a method based on least-squares reverse time migration with plane-wave encoding (P-LSRTM) for rugged topography. Instead of modifying the wave field before migration, we modify the plane-wave encoding function and fill constant velocity to the area above rugged topography in the model so that P-LSRTM can be directly performed from rugged surface in the way same to shot domain reverse time migration. In order to improve efficiency and reduce I/O (input/output) cost, the dynamic en- coding strategy and hybrid encoding strategy are implemented. Numerical test on SEG rugged topography model show that P-LSRTM can suppress migration artifacts in the migration image, and compensate am- plitude in the middle-deep part efficiently. Without data correction, P-LSRTM can produce a satisfying image of near-surface if we could get an accurate near-surface velocity model. Moreover, the pre-stack P- LSRTM is more robust than conventional RTM in the presence of migration velocity errors. 展开更多
关键词 least-squares migration rugged topography plane-wave encoding dynamic encoding hybrid encoding.
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超高效液相色谱-串联质谱法测定调节三高类保健食品中59种非法添加药物 被引量:1
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作者 邵瑞婷 丁学妍 姜洁 《食品科学》 EI CAS CSCD 北大核心 2024年第9期232-242,共11页
本实验建立了调节三高类保健食品中59种非法添加药物的超高效液相色谱-串联质谱检测方法。样品经甲醇提取,QuEChERS净化,氮吹至近干,1 mL 40%甲醇溶液(体积分数)复溶,以乙腈和0.1%甲酸溶液(5 mmol/L乙酸铵)为流动相,经ACQUITY UPLC HSS... 本实验建立了调节三高类保健食品中59种非法添加药物的超高效液相色谱-串联质谱检测方法。样品经甲醇提取,QuEChERS净化,氮吹至近干,1 mL 40%甲醇溶液(体积分数)复溶,以乙腈和0.1%甲酸溶液(5 mmol/L乙酸铵)为流动相,经ACQUITY UPLC HSS T3反相柱梯度分离,超高效液相色谱-串联质谱在正、负离子模式下多反应监测,采用基质外标法定量。结果表明:59种非法添加药物在线性范围内,决定系数(R^(2))均大于0.980,回收率在60.2%~119.5%之间,相对标准偏差在1.2%~15.0%之间。该方法具有前处理较简单、分析时间较短、灵敏度好、准确度高、杂质干扰小等特点,可以用于调节三高类保健食品中多种非法添加药物的检测。 展开更多
关键词 调节三高类保健食品 QuEChERS净化 超高效液相色谱-串联质谱 非法添加药物
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快速分散固相萃取-平行液相色谱-串联质谱法同时测定炸鸡食品中26种性激素
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作者 黄永辉 《食品科技》 CAS 北大核心 2024年第5期314-320,共7页
采用平行液相色谱-串联质谱结合快速分散固相萃取技术,建立了同时测定炸鸡食品中26种性激素残留量的方法。样品以乙腈(水)超声提取,100 mg十八烷基硅烷(C_(18))和100 mg乙二胺-N-丙基硅烷粉末净化,浓缩后以50%甲醇复溶。以Waters ACQUIT... 采用平行液相色谱-串联质谱结合快速分散固相萃取技术,建立了同时测定炸鸡食品中26种性激素残留量的方法。样品以乙腈(水)超声提取,100 mg十八烷基硅烷(C_(18))和100 mg乙二胺-N-丙基硅烷粉末净化,浓缩后以50%甲醇复溶。以Waters ACQUITY UPLC BEH C_(18)为色谱柱,甲醇-2 mmol/L乙酸铵含0.01%氨水溶液为流动相进行梯度洗脱,电喷雾-正负离子切换、多反应监测模式进行测定,基质匹配标准曲线外标法定量。方法学验证表明,在1.0~50.0 μg/L的范围内,26种性激素的线性较好,相关系数(R^(2))均大于0.999,该方法的检出限为0.3~1.0 μg/kg,定量限为1.0~3.0 μg/kg。在炸鸡腿、烤翅和炸鸡块基质中分别进行3水平6平行的加标回收实验,26种性激素的回收率为78.9%~105.3%,相对标准偏差为3.1%~8.4%。所建立的方法简单高效、准确度好、重现性高,适用于炸鸡食品中26种性激素的同时测定。 展开更多
关键词 快速分散固相萃取 平行液相色谱-串联质谱 炸鸡 性激素
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气相色谱-串联质谱法测定豆乳中12种有机磷及氨基甲酸酯类农药残留 被引量:6
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作者 谢瑞龙 梁建英 《乳业科学与技术》 2021年第5期27-31,共5页
建立QuEChERS-气相色谱-串联质谱法测定豆乳中12种有机磷及氨基甲酸酯类农药残留的方法。样品经乙腈提取,柠檬酸盐缓冲条件下分离,无水硫酸镁、乙二胺-N-丙基硅烷化硅胶和C18净化处理,气相色谱-串联质谱仪测定。结果表明:12种农药的定... 建立QuEChERS-气相色谱-串联质谱法测定豆乳中12种有机磷及氨基甲酸酯类农药残留的方法。样品经乙腈提取,柠檬酸盐缓冲条件下分离,无水硫酸镁、乙二胺-N-丙基硅烷化硅胶和C18净化处理,气相色谱-串联质谱仪测定。结果表明:12种农药的定量限均为0.004 mg/kg;标准曲线在5~200 ng/mL范围内线性良好,相关系数>0.99;进行3个不同水平的加标实验,加标回收率为71.8%~114.9%,相对标准偏差为4.6%~13.3%。该方法快速、高效、准确,可用于豆乳中有机磷及氨基甲酸酯类农药残留的测定。 展开更多
关键词 QUECHERS 气相色谱-串联质谱 豆乳 有机磷 氨基甲酸酯
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Influence of complex topography on global solar radiation in the Yangtze River Basin 被引量:4
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作者 WANG Li QIU Xinfa WANG Peifa WANG Xiaoying LIU Aili 《Journal of Geographical Sciences》 SCIE CSCD 2014年第6期980-992,共13页
Global solar radiation(GSR) is the most direct source and form of global energy, and calculation of its quantity is highly complex due to influences of local topography and terrain inter-shielding. Digital elevation... Global solar radiation(GSR) is the most direct source and form of global energy, and calculation of its quantity is highly complex due to influences of local topography and terrain inter-shielding. Digital elevation model(DEM) data as a representation of the complex terrain and multiplicity condition produces a series of topographic factors(e.g. slope, aspect, etc.). Based on 1 km resolution DEM data, meteorological observations and NOAA-AVHRR remote sensing data, a distributed model for the calculation of GSR over rugged terrain within the Yangtze River Basin has been developed. The overarching model permits calculation of astronomical solar radiation for rugged topography and comprises a distributed direct solar radiation model, a distributed diffuse radiation model and a distributed terrain reflectance radiation model. Using the developed model, a quantitative simulation of the GSR space distribution and visualization has been undertaken, with results subsequently analyzed with respect to locality and terrain. Analyses suggest that GSR magnitude is seasonally affected, while the degree of influence was found to increase in concurrence with increasing altitude. Moreover, GSR magnitude exhibited clear spatial variation with respect to the dominant local aspect; GSR values associated with the sunny southern slopes were significantly greater than those associated with shaded slopes. Error analysis indicates a mean absolute error of 12.983 MJm-2 and a mean relative error of 3.608%, while the results based on a site authentication procedure display an absolute error of 22.621 MJm-2 and a relative error of 4.626%. 展开更多
关键词 rugged terrain global solar radiation(GSR) distributed model Digital Elevation Model Yangtze River Basin
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Distributed modeling of direct solar radiation on rugged terrain of the Yellow River Basin 被引量:4
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作者 ZENG Yan QIU Xinfa +1 位作者 LIU Changming JIANG Aijun 《Journal of Geographical Sciences》 SCIE CSCD 2005年第4期439-447,共9页
Due to the influences of local topographical factors and terrain inter-shielding, calculation of direct solar radiation (DSR) quantity of rugged terrain is very complex. Based on digital elevation model (DEM) data... Due to the influences of local topographical factors and terrain inter-shielding, calculation of direct solar radiation (DSR) quantity of rugged terrain is very complex. Based on digital elevation model (DEM) data and meteorological observations, a distributed model for calculating DSR over rugged terrain is developed. This model gives an all-sided consideration on factors influencing th a resolution of 1 km × 1 km for thDSR. Using the developed model, normals of annual DSR quantity wie Yellow River Basin was generated, with DEM data as the general characterization of terrain. Characteristics of DSR quantity influenced by geographic and topographic factors over rugged terrain were analyzed thoroughly. Results suggest that: influenced by local topographic factors, i.e. azimuth, slope and so on, and annual DSR quantity over mountainous area has a clear spatial difference; annual DSR quantity of sunny slope (or southern slope) of mountains is obviously larger than that of shady slope (or northern slope). The calculated DSR quantity of the Yellow River Basin is provided in the same way as other kinds of spatial information and can be employed as basic geographic data for relevant studies as well. 展开更多
关键词 direct solar radiation (DSR) rugged terrain digital elevation model (DEM) distributed model Yellow River Basin
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Simulation of astronomical solar radiation over Yellow River Basin based on DEM 被引量:5
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作者 QIUXinfa ZENGYan +1 位作者 LIUChangming WUXianfeng 《Journal of Geographical Sciences》 SCIE CSCD 2004年第1期63-69,共7页
Based on the developed distributed model for calculating astronomical solar radiation (ASR), monthly ASR with a resolution of 1 km×1 km for the rugged terrains of Yellow River Basin was calculated, with DEM data ... Based on the developed distributed model for calculating astronomical solar radiation (ASR), monthly ASR with a resolution of 1 km×1 km for the rugged terrains of Yellow River Basin was calculated, with DEM data as the general characterization of terrain. This model gives an all-sided consideration on factors that influence the ASR. Results suggest that (1) Annual ASR has a progressive decrease trend from south to north; (2) the magnitude order of seasonal ASR is: summer>spring>autumn>winter; (3) topographical factors have robust effect on the spatial distribution of ASR, particularly in winter when a lower sun elevation angle exists; (4) the ASR of slopes with a sunny exposure is generally 2 or 3 times that of slopes with a shading exposure and the extreme difference of ASR for different terrains is over 10 times in January; (5) the spatial differences of ASR are relatively small in summer when a higher sun elevation angle exists and the extreme difference of ASR for different terrains is only 16% in July; and (6) the sequence of topographical influence strength is: winter>autumn>spring>summer. 展开更多
关键词 astronomical solar radiation (ASR) rugged terrains spatial distributions digital elevation model (DEM)
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基于《中华人民共和国药典》优化丹参中33种禁用农药残留物检测的前处理方法 被引量:4
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作者 杨红 韩玲玲 +3 位作者 雒昱 张亚中 吴德玲 刘军玲 《安徽中医药大学学报》 CAS 2022年第6期82-88,共7页
目的以丹参为研究对象,比较2020年版《中华人民共和国药典》中3类前处理方法对33种禁用农药残留物回收率的影响,进一步优化快速样品处理法(quick,easy,cheap,effective,rugged and safe,QuEChERS)。方法分别从基质效应和回收率方面比较... 目的以丹参为研究对象,比较2020年版《中华人民共和国药典》中3类前处理方法对33种禁用农药残留物回收率的影响,进一步优化快速样品处理法(quick,easy,cheap,effective,rugged and safe,QuEChERS)。方法分别从基质效应和回收率方面比较《中华人民共和国药典》3类前处理方法,并对QuEChERS法进行研究与优化,样品加水后由1%醋酸-乙腈提取,依次加入QuEChERS盐包与QuEChERS净化管盐析净化,提取液经浓缩后分别加入水和内标磷酸三苯酯,结合液相色谱-串联质谱法和气相色谱-串联质谱法以添加水平为定量限浓度水平测定样品的回收率和RSD。结果采用《中华人民共和国药典》前处理方法时,丹参中33种禁用农药(54个单体)在添加水平为定量限浓度水平时,部分农药回收率较低;优化QuEChERS法后,丹参中33种禁用农药(54个单体)在一定浓度下,线性关系良好,r均大于0.990,其回收率为64.43%~127.35%时,RSD均<15%;199批饮片和60批药材中共检出2种农药,甲拌磷检出率为3.86%,克百威检出率为1.93%,但残留量均未超过2020年版《中华人民共和国药典》规定限度。结论优化后的QuEChERS法快速简便,有针对性地对丹参中33种禁用农药残留进行准确检测,对于丹参的生产种植与日常监控具有一定的参考意义。 展开更多
关键词 禁用农药残留 丹参 快速样品处理法 前处理方法
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The glutamate metabotropic receptor 5(GRM5)gene is associated with beef cattle home range and movement tortuosity 被引量:1
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作者 Cristian A.Moreno Garcia Huitong Zhou +5 位作者 David Altimira Robyn Dynes Pablo Gregorini Sadeepa Jayathunga Thomas M.R.Maxwell Jonathan Hickford 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第1期72-87,共16页
Background:The grazing behaviour of herbivores and their grazing personalities might in part be determined genetically,but there are few studies in beef cattle illustrating this.In this study,we investigated for first... Background:The grazing behaviour of herbivores and their grazing personalities might in part be determined genetically,but there are few studies in beef cattle illustrating this.In this study,we investigated for first time the genetic variation within a candidate‘grazing gene',the glutamate metabotropic receptor 5 gene(GRM5),and tested associations between variation in that gene and variation in grazing personality behaviours(GP-behaviours)displayed by free-ranging cows during winter grazing in the steep and rugged rangelands of New Zealand.Mature beef cows(n=303,from 3 to 10 years of age)were tracked with global positioning system(GPS)and,with 5-minutes(min)relocation frequency,various GP-behaviours were calculated.These included horizontal and vertical distances travelled,mean elevation,elevation range,elevation gain,slope,home range and movement tortuosity,variously calculated using daily relocation trajectories with repeated measurements(i.e.,7 to 24 days(d))and satellite-derived digital elevation models(DEM).The different GP-behaviours were fitted into mixed models to ascertain their associations with variant sequences and genotypes of GRM5.Results:We discovered three GRM5 variants(A,B and C)and identified the six possible genotypes in the cattle studied.The mixed models revealed that A was significantly associated with elevation range,home range and movement tortuosity.Similarly,GRM5 genotypes were associated(P<0.05)to home range and movement tortuosity,while trends suggesting association(P<0.1)were also revealed for elevation range and horizontal distance travelled.Most GP-behaviour models were improved by correcting for cow age-class as a fixed factor.The analysis of GP-behaviours averaged per cow age-class suggests that grazing personality is fully established as beef cows reached 4 years of age.Home range and movement tortuosity were not only associated with GRM5 variation,but also negatively correlated with each other(r=-0.27,P<0.001).Conclusions:There seems to be a genetically determined trade-off b 展开更多
关键词 Animal personality Breeding programmes Genetic associations Grazing distribution Grazing patterns Steep and rugged terrain
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QuEChERS-UPLC-MS/MS法同时测定刺梨中11种农药残留 被引量:3
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作者 姚小龙 韩磊 +4 位作者 刘旭东 罗跃 吴琼 安华明 吴小毛 《食品科学》 EI CAS CSCD 北大核心 2022年第16期309-316,共8页
目的:建立高维生素含量刺梨果实中11种常用农药残留量的测定方法。方法:采用添加回收实验筛选和优化QuEChERS前处理方法的提取剂和净化方式,最终选用乙腈提取,N-丙基乙二胺和石墨化碳黑进行净化,以0.1%甲酸溶液和乙腈为流动相,用0.4 mL/... 目的:建立高维生素含量刺梨果实中11种常用农药残留量的测定方法。方法:采用添加回收实验筛选和优化QuEChERS前处理方法的提取剂和净化方式,最终选用乙腈提取,N-丙基乙二胺和石墨化碳黑进行净化,以0.1%甲酸溶液和乙腈为流动相,用0.4 mL/min的流速梯度洗脱;在电喷雾正离子模式下,通过优化各农药离子对的碎裂电压、碰撞能量,以获得最佳响应,采用基质加标准曲线进行定量。结果:经方法验证,11种农药的方法检出限在1.31~8.56μg/kg之间,定量限在4.13~43.57μg/kg之间,线性相关系数(R)在0.9912~0.9999之间;方法选择3个添加水平进行添加回收率实验,回收率在84.5%~103.8%之间,相对标准偏差(n=6)在1.2%~8.5%之间。结论:该方法前处理快速、灵敏、准确,可为刺梨中农药的监管提供技术支持。 展开更多
关键词 刺梨 QUECHERS 超高效液相色谱-串联质谱 农药残留
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UPLC-MS/MS检测肉制品中16种杂环胺前处理方法筛选 被引量:4
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作者 丁晓倩 惠腾 +2 位作者 白雪 王振宇 张德权 《食品科学》 EI CAS CSCD 北大核心 2021年第20期230-237,共8页
采用串联固相萃取法(Extrelut-PRS-C18固相萃取柱萃取法、PRS-C18固相萃取柱萃取法)、MCX固相萃取柱萃取法和分散固相萃取法(QuEChERS(quick, easy, cheap, effective, rugged, and safe)法)4种前处理方法对肉制品中16种杂环胺(heterocy... 采用串联固相萃取法(Extrelut-PRS-C18固相萃取柱萃取法、PRS-C18固相萃取柱萃取法)、MCX固相萃取柱萃取法和分散固相萃取法(QuEChERS(quick, easy, cheap, effective, rugged, and safe)法)4种前处理方法对肉制品中16种杂环胺(heterocyclic amines,HAs)进行提取,并从方法学和提取成本角度综合比较4种方法。结果表明:4种提取方法得到的16种HAs的回收率和精密度及检出限(limit of detection,LOD)和定量限(limit of quantification,LOQ)存在显著差异,其中QuEChERS法回收率和精密度均优于其他3种方法。MCX固相萃取柱萃取法和QuEChERS法的LOD和LOQ优于其他2种方法;MCX固相萃取柱萃取法和QuEChERS法所需经济和时间成本较低。综合分析,QuEChERS法具有快速、简便、便宜、有效、稳固和安全的特点,有利于肉制品中HAs的准确检测,并值得推广应用。 展开更多
关键词 杂环胺 肉制品 回收率 固相萃取 QuEChERS法
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抗恶劣环境加固显示器设计技术 被引量:4
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作者 王连坡 吕清海 《舰船电子工程》 2012年第9期163-165,共3页
介绍了加固显示器的类型,分析了显示器在恶劣环境下的特性,根据不同的特性给出了具体的设计技术,主要介绍了宽温技术、抗振动冲击技术、电磁兼容技术等。
关键词 显示器 加固 宽温 振动冲击 电磁兼容
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Core-Germplasm Construction of <i>Rosa rugosa</i>Collections by CDDP Molecular Markers 被引量:2
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作者 Liyuan Jiang Dekui Zang 《Open Journal of Applied Sciences》 2017年第11期635-645,共11页
A method for constructing core-germplasm of Rosa rugosa in China based on molecular marker data was probed and the optimum core germplasm was established. Studies were initiated to analyze the genetic diversity of 120... A method for constructing core-germplasm of Rosa rugosa in China based on molecular marker data was probed and the optimum core germplasm was established. Studies were initiated to analyze the genetic diversity of 120 rugged roses from 6 different Chinese source populations based on CDDP marker, and a preliminary construction of the core collection was established using stepwise UPGMA clustering sampling method. The 26 core collection resources of R. rugosa collections in China have 20% germplasm samples of initial collection, the retention ratio of polymorphic loci, effective number of alleles (Ne), Nei’s genetic diversity (H) and Shannon information index (I) were respectively 97.52%, 104.16%, 108.38% and 106.18%. The results of t-test showed that no significant difference was found in genetic diversity indexes between the core collection and the original collection. These results also demonstrated that the core collection could stand for original collection excellently. The results show that CDDP molecular technology can be successfully applied to the construction of core germplasm resources of rugged roses. 展开更多
关键词 rugged Rose in China CDDP Markers Genetic Diversity CORE Collection
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