Photopolymerized sol-gel(PSG) columns were prepared using methacryloxypropyltrimethoxysilane as the monomer,toluene as the porogen and hydrochloric acid as the catalyst.Four different photoinitiators such as benzoin m...Photopolymerized sol-gel(PSG) columns were prepared using methacryloxypropyltrimethoxysilane as the monomer,toluene as the porogen and hydrochloric acid as the catalyst.Four different photoinitiators such as benzoin methyl ether,Irgacure 819,Irgacure 1700 and Irgacure 1800 were comparatively used in the reaction solution in the presence and absence of sodium dodecyl sulfate.The above eight solutions were respectively irradiated at 365 nm for 5?10 min in each capillary(75 μm inside diameter) to prepare the porous monolithic sol-gel column by a one-step,in situ,process.The chromatographic behavior of the eight PSG columns were comparatively studied,all of which exhibit reversed-phase character.Using these columns,several neutral compounds,namely thiourea,benzene,toluene,ethyl benzene,biphenyl and naphthalene can be separated from mixtures with a largest column efficiency of 74 470 plate/column for thiourea.Addition of sodium dodecyl sulfate in the polymerization process has a significant influence on the morphology and migration time.展开更多
文摘古湖岸堤是湖面波动的地貌证据,可以用来重建古湖泊演化.古湖岸堤沉积物的准确测年是应用此地貌学证据重建湖泊演化的关键.以我国兴凯湖最低一级湖岸堤——大湖岗为研究对象,采用石英小片技术,应用单片再生剂量法(SAR)对大湖岗2个不同位置的剖面风成砂质沉积物(共13个样品)进行了光释光(OSL)测年.样品石英组分的光释光衰减曲线特征表明,样品的释光信号以快组分为主,预热坪和实验室剂量恢复实验结果表明,SAR法可以用来测量兴凯湖古湖岸堤样品的等效剂量.通过分析样品等效剂量分布情况和比较3种年龄模型(平均值模型、中值模型和最小值模型),认为大湖岗湖滨砂质沉积物在沉积埋藏前石英光释光信号晒退完全,获得的OSL年龄是可信的.年代结果表明,大湖岗采自不同位置的2个剖面的年代范围一致,且各个剖面中所有年代均随地层顺序变化;另外,2个样品的OSL年龄与同层位的炭屑样品的14C年代结果在误差范围内一致,进一步表明OSL测年技术可以获得可靠的兴凯湖岸堤沉积物的年龄.尽管与前人使用热释光(TL)测年方法研究大湖岗形成年代有较大差别,本文认为兴凯湖最低一级古湖岸堤——大湖岗形成于距今约1.24—0.50 ka.
基金Project(20611140646) supported by the NSFC-KOSEF Scientific Cooperation Program project(2006HANCET-01) supported by Program for New Century Talents of University of Henan Provinceproject(2005-461-140) supported by Program for Backbone Teacher in Henan Province
文摘Photopolymerized sol-gel(PSG) columns were prepared using methacryloxypropyltrimethoxysilane as the monomer,toluene as the porogen and hydrochloric acid as the catalyst.Four different photoinitiators such as benzoin methyl ether,Irgacure 819,Irgacure 1700 and Irgacure 1800 were comparatively used in the reaction solution in the presence and absence of sodium dodecyl sulfate.The above eight solutions were respectively irradiated at 365 nm for 5?10 min in each capillary(75 μm inside diameter) to prepare the porous monolithic sol-gel column by a one-step,in situ,process.The chromatographic behavior of the eight PSG columns were comparatively studied,all of which exhibit reversed-phase character.Using these columns,several neutral compounds,namely thiourea,benzene,toluene,ethyl benzene,biphenyl and naphthalene can be separated from mixtures with a largest column efficiency of 74 470 plate/column for thiourea.Addition of sodium dodecyl sulfate in the polymerization process has a significant influence on the morphology and migration time.