Liquid chromatography tandem mass chromatography （LC-MS/MS） is an important hyphenated technique for quantitative analysis of drugs in biological fluids. Because of high sensitivity and selectivity, LC-MS/MS has bee...Liquid chromatography tandem mass chromatography （LC-MS/MS） is an important hyphenated technique for quantitative analysis of drugs in biological fluids. Because of high sensitivity and selectivity, LC-MS/MS has been used for pharmacokinetic studies, metabolites identification in the plasma and urine. This manuscript gives comprehensive analytical review, focusing on chromatographic separation approaches （column packing materials, column length and mobile phase） as well as different acquisition modes （SIM, MRM） for quantitative analysis of glucocorticoids and stimulants. This review is not meant to be exhaustive but rather to provide a general overview for detection and confirmation of target drugs using LC-MS/MS and thus useful in the doping analysis, toxicological studies as well as in pharmaceutical analysis.展开更多
This paper deals with the asymptotic behavior of solutions of the stochastic g-Navier-Stokes equation driven by nonlinear noise.The existence and uniqueness of weak pullback mean random attractors for the equation in ...This paper deals with the asymptotic behavior of solutions of the stochastic g-Navier-Stokes equation driven by nonlinear noise.The existence and uniqueness of weak pullback mean random attractors for the equation in Bochner space is proven for when the diffusion terms are Lipschitz nonlinear functions.Furthermore,we also establish the existence of invariant measures for the equation.展开更多
针对纳米材料在钻井液中团聚的问题,通过分子设计,改进纳米材料的表面性能,以改性纳米二氧化硅为核,通过接枝柔性聚合物,合成了一种纳米封堵降滤失剂。通过引入强的吸附基团和疏水基团,聚合物分子的亲疏水、氢键等协同作用形成空间的网...针对纳米材料在钻井液中团聚的问题,通过分子设计,改进纳米材料的表面性能,以改性纳米二氧化硅为核,通过接枝柔性聚合物,合成了一种纳米封堵降滤失剂。通过引入强的吸附基团和疏水基团,聚合物分子的亲疏水、氢键等协同作用形成空间的网架结构,使合成的纳米封堵降滤失剂能够以纳米级尺度分散在钻井液中,其在钻井液中纳米级粒度的含量高达59.3%,其不仅具有优异的降滤失性能,同时具有柔性可变形性,还能够吸附在岩石表面,提高纳米材料对微裂缝和小孔隙的封堵能力。以合成的纳米降滤失剂为核心处理剂,并优选出配套的纳米润滑剂、纳米抑制剂,形成纳米钻井液体系。该体系的抗温达150℃,API滤失量在2.4 m L以下、高温高压滤失量在9.8 m L以下、润滑系数不大于0.04,渗透率恢复值不小于91%、目的层井段岩屑回收率≥90.5%。该体系在大港油田枣1510井的应用中表现出良好的润滑性和保护油气层效果。展开更多
文摘Liquid chromatography tandem mass chromatography （LC-MS/MS） is an important hyphenated technique for quantitative analysis of drugs in biological fluids. Because of high sensitivity and selectivity, LC-MS/MS has been used for pharmacokinetic studies, metabolites identification in the plasma and urine. This manuscript gives comprehensive analytical review, focusing on chromatographic separation approaches （column packing materials, column length and mobile phase） as well as different acquisition modes （SIM, MRM） for quantitative analysis of glucocorticoids and stimulants. This review is not meant to be exhaustive but rather to provide a general overview for detection and confirmation of target drugs using LC-MS/MS and thus useful in the doping analysis, toxicological studies as well as in pharmaceutical analysis.
基金supported by the National NaturalScience Foundation of China(11871138)the Sichuan Science and Technology Program(2023NSFSC0076)。
文摘This paper deals with the asymptotic behavior of solutions of the stochastic g-Navier-Stokes equation driven by nonlinear noise.The existence and uniqueness of weak pullback mean random attractors for the equation in Bochner space is proven for when the diffusion terms are Lipschitz nonlinear functions.Furthermore,we also establish the existence of invariant measures for the equation.
文摘针对纳米材料在钻井液中团聚的问题,通过分子设计,改进纳米材料的表面性能,以改性纳米二氧化硅为核,通过接枝柔性聚合物,合成了一种纳米封堵降滤失剂。通过引入强的吸附基团和疏水基团,聚合物分子的亲疏水、氢键等协同作用形成空间的网架结构,使合成的纳米封堵降滤失剂能够以纳米级尺度分散在钻井液中,其在钻井液中纳米级粒度的含量高达59.3%,其不仅具有优异的降滤失性能,同时具有柔性可变形性,还能够吸附在岩石表面,提高纳米材料对微裂缝和小孔隙的封堵能力。以合成的纳米降滤失剂为核心处理剂,并优选出配套的纳米润滑剂、纳米抑制剂,形成纳米钻井液体系。该体系的抗温达150℃,API滤失量在2.4 m L以下、高温高压滤失量在9.8 m L以下、润滑系数不大于0.04,渗透率恢复值不小于91%、目的层井段岩屑回收率≥90.5%。该体系在大港油田枣1510井的应用中表现出良好的润滑性和保护油气层效果。
