Results 1 to 10 of about 818 (141)

[Chemical diversity of dissolved organic matter revealed by ultra performance liquid chromatography-Fourier transform ion cyclotron resonance mass spectrometry]. [PDF]

open access: yesSe Pu, 2023
采用傅里叶变换离子回旋共振质谱(FT-ICR MS)结合四极检测技术,对水体、气溶胶和土壤样品中溶解性有机质(DOM)进行在线超高效液相色谱(UPLC)-质谱分析。3种环境样品主要组成为强极性含盐化合物、富氧低饱和度的单宁酸类化合物、低氧高饱和度的木质素类化合物及蛋白/氨基糖类化合物。UPLC-FT-ICR MS适合分析DOM的分子组成,在水体、气溶胶和土壤DOM中能够有效匹配分子式的质谱峰数目分别为12027、15593和8029个。质谱数据经可视化处理后发现,水体样品的特有组分主要出现在0 ...
Ma C, Ni HX, Qi YL.
europepmc   +2 more sources

水华微囊藻(Microcystis flos-aquae)生长周期中腐殖酸的释放特性

open access: yes, 2015
由于严重的水体富营养化,太湖长期暴发蓝藻水华,这些蓝藻在代谢及消亡过程中大量释放包括腐植酸在内的有机物,不仅影响供水水质,并且进一步加重了水华程度.以太湖水华优势藻种——水华微囊藻(Microcystis flos-aquae T34)为研究对象,对藻株生长周期中的藻细胞、浮游细菌进行计数,并使用TOC仪与三维荧光光谱对培养液中提取的腐殖酸进行定量与定性分析,探究水华微囊藻在生长过程中藻细胞密度、浮游细菌密度与腐殖酸浓度的变化规律.结果表明,培养液中腐殖酸浓度的变化趋势与细菌数量变化趋势一致 ...
李仁辉, 谷依露, 高小峰
core   +4 more sources

硼酸官能化金属-有机骨架磁性纳米复合材料的制备及其在茶叶农药残留检测中的应用

open access: yesSe pu = Chinese journal of chromatography, 2021
在茶叶的农药残留检测中,茶多酚及色素具有很强的基质效应,严重影响了色谱检测结果。该文将Fe3O4磁性纳米粒子与硼酸官能化金属有机骨架(BA-MOF)材料相结合,制备出一种对茶多酚等基质具有高效捕获能力的吸附材料Fe3O4@BA-MOF。结合气相色谱-质谱联用技术,建立了一种茶叶样品中农药残留的有效分析方法。通过在金属有机骨架结构中引入硼酸配体,将其作为顺式二醇的识别位点,实现对茶多酚的高效捕获。这种新型材料具有快速磁分离,比表面积高,功能位点丰富等优点。通过傅里叶变换红外光谱 ...
Fengya Wang, Liang Feng
semanticscholar   +1 more source

Characteristics and sources of typical pollution components in mine water in the border area of Inner Mongolia and Shaanxi [PDF]

open access: yes, 2023
The border area between Mongolia and Shaanxi is the core area for China’s energy security. However, a large number of mine water produced in the process of coal mining contains a variety of pollution components.
Hao WANG   +4 more
core   +1 more source

Effect of Adsorption of Metal Elements Ni and V on the Structure of Humin [PDF]

open access: yes, 2023
BACKGROUNDBlack shales are mostly developed in special periods in geological history. They not only record the evolution characteristics of paleoenvironment, paleoclimate and paleontology, but also are carriers of organic matter, oil and gas and various ...
Jianping CHENG   +5 more
core   +1 more source

“一锅法”制备聚(苯乙烯-丙烯酸)共聚物改性的硅基固定相及其在混合模式液相色谱中的应用

open access: yesSe pu = Chinese journal of chromatography, 2023
聚合物作为一种来源广泛、功能基团丰富、生物相容性良好的修饰配体,被广泛用作硅基色谱固定相。本工作以苯乙烯和丙烯酸为聚合单体,乙烯基三甲氧基硅烷为硅烷偶联剂,通过自由基聚合反应一锅法制备了聚(苯乙烯-丙烯酸)共聚物改性的硅基固定相(SiO2@P(St-b-AA))。傅里叶红外光谱、热重分析、扫描电镜、N2吸附-脱附、Zeta电势分析等表征手段证明了该固定相已成功合成,且保持了良好的介孔球形结构。在固定相性能评价中,分别采用疏水性分析物、极性分析物和离子型化合物作为探针 ...
Xiaoqing Wang   +5 more
semanticscholar   +1 more source

基于阳离子型金属有机骨架混合基质膜的分散固相萃取-超高效液相色谱-串联质谱法测定水中7种苯氧羧酸类除草剂

open access: yesSe pu = Chinese journal of chromatography, 2021
离子型金属有机骨架材料(iMOFs)对离子型化合物具有良好的选择吸附性,利用水热法合成了一种金属有机骨架材料MIL-101-NH2,以聚偏二氟乙烯(PVDF)为交联剂将其制备成混合基质膜(MMM),然后用三氟甲烷磺酸甲酯进行季胺基功能化改性,最终得到阳离子型金属有机骨架膜材料MIL-101-$NMe_{3}^{+}$-PVDF MMM,采用分散固相萃取方式富集水中的苯氧羧酸类除草剂,建立了一种基于阳离子型MOF混合基质膜的分散固相萃取-超高效液相色谱-串联质谱(UPLC-MS/MS ...
Xu Ji   +4 more
semanticscholar   +1 more source

尿素包合法从葡萄籽油中富集高纯度 亚油酸甲酯及包合Enrichment of high purity methyl linoleate from grape seed oil by urea adduction and characterization of adduction complexes物表征分析

open access: yesZhongguo youzhi, 2022
为提升葡萄籽的使用价值,以葡萄籽油为原料,采用尿素包合法富集高纯度亚油酸甲酯。研究了脂肪酸甲酯与尿素质量比、尿素与95%乙醇质量比、包合时间和包合温度对包合效果的影响,并采用傅里叶变换红外光谱(FTIR)、X射线衍射(XRD)和扫描电子显微镜(SEM)对空白尿素结晶物和包合固形物进行表征。结果表明:制备高纯度亚油酸甲酯的最佳工艺条件为脂肪酸甲酯与尿素质量比1∶ 2、尿素与95%乙醇质量比1∶ 4、包合温度5 ℃、包合时间10 h,在此条件下得到的亚油酸甲酯含量为94.83%,收率为40.41 ...
曾俊1,2,岳杨1,任小娜1,2,茹仙古丽·尤努斯1,2,姜蕾1,2 ZENG Jun1,2, YUE Yang1, REN Xiaona1,2, RUXIANGULI Younusi1,2, JIANG Lei1,2
doaj   +1 more source

Distribution and Seasonal Variations of Chromophoric Dissolved Organic Matter (CDOM) in the Bohai Sea and the North Yellow Sea [PDF]

open access: yes, 2018
UV-Vis spectral data and a fluorescence excitation-emission matrix (EEM) was analyzed for the surface, middle, and bottom layer water samples from the Bohai Sea and North Yellow Sea in April, August, and December of 2016 and February of 2017 ...
刘兆冰   +3 more
core   +2 more sources

The hydrothermal alteration types and zoning features of Ordovician carbonate in Tarim Basin(塔里木盆地奥陶系碳酸盐岩热液蚀变类型及蚀变流体的分带特征)

open access: yesZhejiang Daxue xuebao. Lixue ban, 2019
已探明塔里木盆地下古生界碳酸盐岩地层储量巨大。对塔里木盆地西北部柯坪-巴楚-阿图什一带的4 块区域开展了系统的野外和重点观测工作,包括蓬莱坝剖面、柯坪水泥厂剖面、托普郎剖面等。本研究通过考察塔里木盆地奥陶系碳酸盐岩热液溶蚀及相关现象。从野外产状、伴生关系以及矿物岩石学特征角度解剖奥陶系地层中热液矿物组合的地质特征。研究表明,该区域存在富镁流体、富氟流体和富硫流体3 种流体,分别来源于封存卤水、火成活动和TSR 热液。不同性质流体蚀变具有相似的分带性。
DINGQian(丁茜)   +4 more
doaj   +1 more source

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